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Species Status Assessment Report for the Furbish’s lousewort ● Version 1.1
Species Status Assessment Report for (Pedicularis furbishiae) Furbish’s Lousewort Version 1.1
Painting by Kate Furbish Lousewort From Plants and flowers of Maine: Kate Furbish's Watercolors, courtesy of Rowman & Littlefield
September 2018 Northeast Region (Region 5) East Orland, Maine
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Species Status Assessment Report for the Furbish’s lousewort ● Version 1.1
This document was written by Mark McCollough, Ph.D., Endangered Species Biologist, Maine Ecological Services Field Office, Northeast Region, East Orland, Maine.
We thank the following individuals who provided substantive information and insights for the Species Status Assessment (SSA) analysis: Don Cameron and Molly Docherty (Maine Natural Areas Program), Andy Cutko (Maine Chapter of The Nature Conservancy), Spyros Beltaos (Environment Canada),Dr. Graham Forbes and Maureen Toner (University of New Brunswick) and Eric Menges (Archibold Biological Station), and other members of the U. S. Fish and Wildlife Service (USFWS) SSA Core Team for their helpful advice and discussion: Mary Parkin, Anna Harris, and Diane Opper.
Suggested reference: U.S. Fish and Wildlife Service. 2018. Species status assessment for the Furbish’s lousewort (Pedicularis furbishiae).Version 1.1. Maine Field Office, East Orland, Maine. 59 pages + 3 appendices.
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Species Status Assessment Report for the Furbish’s lousewort ● Version 1.1
Executive Summary
This Species Status Assessment (SSA) report is a comprehensive review of the biology and status of the Furbish’s lousewort (Pedicularis furbishiae), a perennial herb that was listed as endangered in 1978 under the Endangered Species Act of 1973, as amended (Act). The purpose of this report is to evaluate the viability of the Furbish’s lousewort using conservation biology principles of resiliency, redundancy, and representation (together, the 3Rs). Specifically, we identified the species’ ecological requirements for survival and reproduction at the individual, population, and species levels, and described the factors, both positive and negative, influencing the Furbish’s lousewort viability. We evaluated the species’ current levels in terms of the 3Rs, and forecast changes into the future under a range of plausible scenarios. This SSA was developed to address the Department of the Interior’s Strategic Plan for fiscal years 2018-2022 that requires that all recovery plans have quantitative criteria for what constitutes a recovered species. Recovery plans for the Furbish’s lousewort were developed in 1983 and 1991and include criteria for downlisting the species from endangered to threatened, but do not contain quantitative criteria for delisting the species.
The Furbish’s lousewort (Pedicularis furbishiae) is an herbaceous perennial plant that occurs on the intermittently flooded, ice-scoured banks of the Saint John River in northern Maine. It is endemic to Maine with a few, small subpopulations in northwestern New Brunswick, Canada and is found nowhere else in the world. The metapopulation of Furbish’s lousewort is comprised of about 20 small subpopulations associated with suitable habitat that occur along a 225 km (140 mile) section of the St. John River. It was Maine’s first officially listed endangered plant species, and it is listed as endangered in the province of New Brunswick.
The SSA framework considers a species’ life history and ecological requirements to understand how the species maintains itself over time. Therefore, we evaluated the ecological requirements of individual lousewort plants and populations and the current and possible future conditions to ascertain the viability of the population. In this SSA report, we evaluated the current condition of the species, as informed by past and present circumstances, and described it in terms of the 3Rs.
To assess resiliency, we evaluated how the health of subpopulations contributes to their ability to sustain themselves in the face of environmental variation and stochastic events. We reviewed the abundance of flowering and nonflowering individuals and colonization of populations through seed dispersal mechanisms. Lousewort populations are dependent on periodic ice scour and flooding, and the frequency and severity of ice scour and flooding are the primary environmental factors affecting the resiliency of the species. We assessed how climate change and development affect the resiliency of the species.
To assess redundancy, we evaluated how the distribution and status of subpopulations contribute to the species’ ability to withstand catastrophic events. We examine how climate change and current and future development are likely to affect the number, population size, and distribution of populations.
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To assess representation, we evaluated how the species’ range of variation contributes to its ability to adapt to near and long-term changes in the environment. We evaluated the species’ genetic diversity, morphological variability, phenological variability, and habitat variability. We evaluated the current condition of the 20 subpopulations using three population criteria and three habitat criteria. All but one of the six upriver subpopulations were in fair to good condition. Twelve of fourteen downriver subpopulations were in poor condition. Most upriver subpopulations still retain their resilience to withstand stochastic events (periodic ice scour and flooding), but the downriver subpopulations have lost the resilience they had in the late 1980s. Six of these subpopulations are now locally extirpated. Most subpopulations are at low numbers and thus the metapopulation is less resilient than it was from the 1980s through 2010.
The metapopulation lost redundancy with the decline and local extirpation of downriver subpopulations and thus it is less able to withstand catastrophic events (widespread, severe ice scour or repeated, smaller ice scour events). The metapopulation declined substantially but rebounded after catastrophic ice scour events in 1989 and 2003. A similar decline occurred in 2011 after repeated, mid-winter ice scour events, but the metapopulation has not yet recovered. There is a marked difference in habitat conditions and stressors upriver and downriver. Upriver habitat is more extensive and occurs in a managed industrial forest. Downriver habitats (including New Brunswick) are small, fragmented, eroded, and lacking an adequate forested riparian buffer in a landscape dominated by agricultural and moderate development. Stressors most likely to affect the current viability of the species are development and climate change.
Using the same methodology and criteria described above for assessing current condition, we modeled three future plausible scenarios to assess the potential viability of Furbish’s lousewort in the years 2030 and 2060. By 2030 we believe it is very likely that, in all three scenarios, the metapopulation of Furbish’s lousewort will continue to decline due to local extirpations of downriver subpopulations and it is likely that the overall viability of the metapopulation will decline. By 2060 we believe it is likely that in one scenario, the most optomistic, the overall viability of the metapopulation will be greatly reduced from current conditions, and a few subpopulations will persist upriver in Maine. We believe it is very likely in both the continuation and worse case scenarios that the metapopulation will no longer be viable; it will be extirpated throughout most of its range; and the few plants that remain would be concentrated at upriver sites.
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Table of Contents
Chapter 1. Introduction, Data, and Analytical Framework...... 1 1.1 Regulatory History...... 2 1.2 Analytical Framework ...... 2 1.2.1 Resiliency...... 3 1.2.2 Redundancy...... 3 1.2.3 Representation...... 4 Chapter 2. Species Ecology and Needs...... 4 2.1 Species Description, Taxonomy and Genetics...... 4 2.2 Geographic Range and Habitat Description ...... 8 2.3 Individual-level Ecology...... 10 2.4 Population-level Ecology...... 11 2.5 Species-level Ecology...... 12 Chapter 3. Species Current Condition...... 15 3.1 Population Trends ………………………...... 15 3.2 Factors Affecting Current Condition ...... 21 3.2.1 Development...... 22 3.2.2 Climate Change...... 23 3.2.3 Consideration of other stressors………………………………………………………27 3.2.4 Conservation Actions...... 28 3.3. Assessment of Current Condition ...... 31 3.3.1 Analytical Approach………………………………………………………………….31 3.3.2 Results……………………………………………………………………………….33 3.3.2.1 Resiliency...... 37 3.3.2 .2 Redundancy...... 38 3.3.2.3 Representation...... 39 3.4 Synthesis of Current Condition...... 39 Chapter 4. Analysis of Future Conditions...... 40 4.1 Introduction to Future Scenarios...... 40 4.2 Scenarios...... 48 4.3 Predicting Future Conditions ...... 52 4.3.1 Continuation Scenario...... 52 4.3.2. Best Case Scenario...... 56 4.3.3. Worse Case Scenario ...... 56 Chapter 5. Synthesis and Viability...... 57 Literature Cited ...... 60 Glossary of terms ...... 70 Appendices……………………………………………………………………………………….72
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Species Status Assessment Report for the Furbish’s lousewort ● Version 1.1
Chapter 1. Introduction, Data, and Analytical Framework
This report summarizes the results of a Species Status Assessment analysis conducted for the Furbish’s lousewort (Pedicularis furbishiae), an herbaceous perennial plant that occurs on the intermittently flooded, ice-scoured banks of the Saint John River in northern Maine. It is endemic (a species unique to a defined geographic location) to Maine with a few, small subpopulations in northwestern New Brunswick, Canada and is found nowhere else in the world. The metapopulation of the Furbish’s lousewort comprises about 20 subpopulations associated with suitable habitat that occur along portions of a 225 kilometer (km) (140 mile (mi)) section of the St. John River. In 1978 the species was among the first plant species listed as endangered on the United States List of Endangered and Threatened Wildlife and Plants. In 1980 it was listed as Endangered by the Committee On The Status of Endangered Wildlife In Canada (COSEWIC). NatureServe (2017) ranks the Furbish’s lousewort as G1G2, Globally Critically Imperiled. It was Maine’s first officially listed endangered plant species, and it is listed as endangered in the province of New Brunswick. United States recovery plans for the Furbish’s lousewort (U.S. Fish and Wildlife Service 1983 and revised in 1991) include criteria for down-listing the species to threatened, but there are no delisting criteria. The Department of the Interior’s Strategic Plan for Fiscal Years 2018-2022 (U.S. Department of the Interior 2018, p. 18) Agency Priority Performance Goals (APPG) requires that by September 30, 2019, all Fish and Wildlife Service recovery plans will have quantitative criteria for what constitutes a recovered species. This SSA report provides the scientific basis to meet this goal.
Using the SSA Framework (USFWS 2016, entire), this report provides an in-depth review of the species’ biology and stressors, an evaluation of its biological status, and an assessment of the resources and conditions needed to maintain long-term viability. The intent is for the SSA report to be easily updated as new information becomes available and to support all functions of the Endangered Species Program from listing decisions to consultations to recovery. As such, the SSA report will be a living document upon which other documents, such as listing rules, recovery plans, and 5-year reviews, would be based if the species remains listed or is proposed for a change in listing status under the Act.
This SSA report for the Furbish’s lousewort is intended to provide the biological support for a decision concerning the listing status of the species; whether to retain the species as endangered, to down-list the species to threatened, or to propose removing the species from the Federal endangered species list. However, the SSA report does not recommend or result in a decision by the Service on whether this taxon should be proposed for listing as a threatened species or delisted. Instead, this SSA report provides a review of the available information strictly related to the biological status of the Furbish’s lousewort. The listing decision will be made by U.S. Fish and Wildlife Service (Service) decision makers after reviewing this report and all relevant laws, regulations, and policies. The results of a listing decision will be explained in a 5-year status review. Any decision to change the listing status of the Furbish’s lousewort from its current designation as endangered will be announced in the Federal Register with appropriate opportunities for public input.
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1.1 Regulatory History
The Furbish’s lousewort was among the first plant species added to the United States List of Endangered and Threatened Wildlife and Plants in 1978 (43 FR 17910). A petition to delist the Furbish’s lousewort, dated February 3, 1997, was submitted by Rob Gordon on behalf of the National Wilderness Institute (Gordon 1997). The petition requested that the Service remove the Furbish’s lousewort (and other species) on the basis of data error. In 2005, the Service found that the petition did not provide substantial information to indicate that the petitioned action may be warranted (70 FR 46467). The Service also used the petition finding as a means of notifying the public of its intent to initiate a 5-year status review for the species in 2006. In 2007, the Service published a 5-year status review with a recommendation to downlist the species to threatened (USFWS 2007). The recovery plan does not include delisting criteria. In the 5-year review, we found that the downlisting criteria in the 1991 recovery plan were not met. However, a change in listing status to threatened was warranted because the Dickey-Lincoln hydropower project was no longer a threat, the species’ population rebounded from several severe ice scour events, the population was widely distributed, and it is unlikely that a single catastrophic event could extirpate the species. We recommended that delisting should not be considered until more information becomes available regarding new threats, particularly residential development and climate change that is increasing the frequency and severity of ice jams and flooding events (USFWS 2007, p.13). We identified information needs before revising the listing status including the degree of threat from residential development and climate change, and a population viability model (USFWS 2007, pp.13-14). The Service did not downlist the Furbish’s lousewort to threatened status. In 2010, we notified the public of our intent to initiate a 5-year status review (75 FR 47025). A 5-year review and listing recommendation will be completed after this SSA report is completed, and Service decisionmakers recommend the future listing status of the Furbish’s lousewort.
1.2 Analytical Framework
The SSA assesses the ability of the Furbish’s lousewort metapopulation to maintain viability over time. To assess the Furbish’s lousewort viability, we used the three conservation biology principles of resiliency, redundancy, and representation, or the “3Rs” (Shaffer and Stein 2000, pp. 308-310; USFWS 2016, entire). These principles are generally described later in this chapter, and more specifically for the Furbish’s lousewort in Chapter 2. Our approach for assessing the Furbish’s lousewort viability involved three stages. First, in Chapter 2 we described the species’ ecology in terms of the 3Rs. Specifically, we identified the ecological requirements for survival and reproduction at the individual, population, and species levels. Second, in Chapter 3 we determined the baseline condition of the species using its ecological requirements. We assessed the species’ current condition in relation to the 3Rs, and identified past and ongoing factors (stressors and conservation actions) that led to the species’ current condition. Third, in Chapter 4 we used the current conditions along with the predictions for the effects of future factors, both positive and negative, that may influence the species to project the likely future condition of the Furbish’s lousewort under a range of plausible scenarios. Finally, in Chapter 5 we described the viability of the Furbish’s lousewort over time through a synthesis of current (influenced by past and ongoing factors) and future conditions analyses.
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Viability is the ability to sustain populations over time. Therefore, a species must have a sufficient number and distribution of healthy populations to withstand changes in its biological (e.g., novel diseases, predators) and physical (e.g., climate) environment, environmental stochasticity (e.g., wet or dry, warm or cold years), and catastrophes (e.g., severe and prolonged droughts, floods). Viability is not a single state, viable or not viable; rather there are degrees of viability, ranging from not viable to high viability. Generally speaking, the more resiliency, redundancy, and representation a species has, the more protected it is against changes in the environment, the more it can tolerate stressors (one or more factors that may be acting on the species or its habitat, causing a negative effect), the better able it is to adapt to future changes, and thus, the more viable it is. The 3Rs framework (assessing the health, number, and distribution of Furbish’s lousewort populations relative to the frequency and magnitude of environmental stochasticity and catastrophic events across its historical range of adaptive diversity) is useful for describing a species’ degree of viability.
1.2.1 Resiliency
Resiliency is the ability of populations to sustain themselves in the face of environmental variation and stochastic events. Environmental variation includes normal year-to-year variation in rainfall and temperatures, as well as unseasonal weather events. Stochastic events include ice scour, flooding, and storms. Simply stated, resiliency is having the means to recover from “bad years” and disturbances. To be resilient, a species must have healthy populations; that is, populations that are able to sustain themselves through good and bad years. The healthier the populations and the greater number of healthy populations, the more resiliency a species possesses. For many species, resiliency is also affected by the degree of connectivity among populations. Connectivity among populations increases the genetic health of individuals (heterozygosity) within a population and bolsters a population’s ability to recover from disturbances via rescue effect (immigration).
1.2.2 Redundancy
Redundancy is the ability of a species to withstand catastrophic events. Redundancy protects species against the unpredictable and highly consequential events for which adaptation is unlikely. In short, it is about spreading the risk. In general, redundancy is measured at the species level, and is best achieved by having multiple populations widely distributed across the species’ range. Having multiple populations reduces the likelihood that all populations would be affected simultaneously, while having widely distributed populations reduces the likelihood of populations possessing similar vulnerabilities to a catastrophic event. Given sufficient redundancy, single or multiple catastrophic events are unlikely to cause the extinction of a species. Thus, the greater redundancy a species has, the more viable it will be. For most species, the more populations and the more diverse or widespread that these populations are, the more likely it is that the ability to withstand catastrophic events will be preserved. Having multiple populations distributed across the range of the species will help preserve the breadth of adaptive diversity, and hence, the evolutionary flexibility of the species.
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1.2.3 Representation
Representation is the ability of a species to adapt to near and long-term changes in the environment; it’s the evolutionary capacity or flexibility of a species. Representation, as measured at the species level, is the range of variation found in a species, and this variation, called adaptive diversity, is the source of species’ adaptive capabilities. Representation can, therefore, be measured through the breadth of adaptive diversity of the species. The greater the adaptive diversity, the more responsive and adaptable the species will be over time, and thus, the more viable the species is.
Maintaining adaptive diversity includes conserving both the ecological diversity and genetic diversity of a species. By maintaining these two sources of adaptive diversity across a species’ range, the responsiveness and adaptability of a species over time is preserved. Ecological diversity is the physiological, ecological, and behavioral variation exhibited by a species across its range. Genetic diversity is the number and frequency of unique alleles within and among populations.
Chapter 2. Species Ecology and Needs
In this chapter, we briefly describe the Furbish’s lousewort taxonomy and life history characteristics at the individual, population, and species levels. This is not an exhaustive review of the species’ natural history; rather, it provides the information relevant to understanding the ecological basis for the SSA analyses presented in Chapters 3-5.
2.1 Species Description, Taxonomy and Genetics
Description and life cycle Furbish’s lousewort is recognized early in the growing season by a basal rosette of deeply cleft or fern-like leaves. By mid-summer mature plants produce one or more flowering stems (scapes) that grow to about 50-80 cm (20-30 inches) in height. The stems have alternate, widely-spaced, fernlike leaves along their length and are topped by a tight cluster (inflorescence) of small, yellow, tube-like flowers that bloom only a few at a time. The plant has two distinct growth stages; vegetative (immature, non-flowering) individuals that grow as a basal rosette of leaves and reproductive (flowering) plants (figure 1).
The life cycle of the Furbish’s lousewort is summarized in table 1. The Furbish’s lousewort does not spread clonally, and plants are established exclusively by sexual reproduction and seed (Stirrett 1980, p. 23, Menges 1990, p. 53). Flowering occurs at a minimum of 3 years (or possibly more) once plants reach a certain size (leaf area). Reproductive plants emerge in May as a rosette of leaves and then produce an average of 2 or 3, flowering stems, each stem having one or more spike-like inflorescences and each inflorescence having up to 25 flowers. Flowers bloom several at a time from about July 10 to August 30 (Stirrett 1980, p. 24; Menges et al. 1986). Furbish’s lousewort is an obligate outcrosser (must be cross-pollinated by a nearby plant) (Macior 1978, Gawler 1983 p. 26). It is pollinated by a single species of bumble bee, the half-black bumble bee (Bombus vagans), that has unique behaviors and tongue length to trigger the pollen mechanisms of the lousewort (Macior 1978). About 50 percent of flowers produce egg-shaped seed capsules
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that ripen in late-September after which the tiny (1mm) seeds are dropped (Menges et al. 1985, 1986; Gawler 1983, p. 27, Gawler et al. 1986, entire). Seeds lack mechanisms for wind or animal dispersal, and most drop near the parent plant. Each mature plant tends to form a colony around itself. During spring floods, it is conceivable that some seeds may disperse down-river (Stirrett 1980, pp. 26-27; Menges 1990, p. 53). The seeds germinate in moist, cool microhabitats having minimal herbaceous or woody plant competition or leaf litter, such as moss-covered soil or parts of the bank that are constantly wet. Furbish lousewort lacks seed dormancy or a seed bank; seedlings result only from the previous year’s reproduction (Menges 1990, p. 54). Seedlings emerge in June through August and have two true leaves during their first growing season (Gawler et al. 1987). At least three years are required for an immature plant to grow to minimum flowering size (USFWS 1991, p. 18). Like most species of Pedicularis, the lousewort seedlings are obligate hemiparasites and obtain part of their nutrition from root attachments (haustoria) with a perennial host plant. The Furbish’s lousewort seem to be a host-generalist, perhaps relying on nitrogen-fixing host plants in the mineral poor soil in which it grows (Macior 1980, entire). Adult plants appear to have no haustoria (USFWS 1983), but this may be because of the difficulty of excavating plants with intact parasitic root connections (Piehl 1963, p. 979). It is not known how the abundance of suitable host plants affects seedling growth and survival (USFWS 1991, p. 22). The lifespan of adult flowering plants is uncertain, but is probably limited to no more than 10 or 15 years because of competition with other plants and the likelihood of periodic flooding and ice-scour.
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Figure 1. Images of the Furbish’s lousewort and its habitat.
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Table 1. Summary of life cycle of Furbish’s lousewort by life stages.
Life Stage Description, characteristics
Seed • Seeds produced in capsules • 7 to 17 seed capsules per inflorescence; up to 50 seed capsules per mature plant • Seeds ripen in late-September; capsule dehisce; seeds drop; limited dispersal capability • Seeds overwinter and germinate the following June through August • Seeds lack long-term seed dormancy; no seed bank Seedlings • Develop two true leaves (only 6 mm; ¼ inch) in height during the initial growing season • Seedlings are hemiparasitic; host generalists, perhaps nitrogen fixing plants • Rosette of leaves at ground level; difficult to find • Take three or more years to grow to sufficient size to produce flowers Vegetative • Mature plants are perennial, emerge in May and by early June produce a crown and of basal leaves (rosette) up to 15 cm (6 inches) in diameter Flowering • Mature plants may be hemiparasitic in nutrient-poor soils, unknown plants • Mature plants produce just one or two flowering stems (scapes) in their first year; may produce an average of 2 to 3 flowering stems in subsequent years. • Each stem may have several inflorescences (maximum of 25 total per plant) • Each inflorescence has about 20 flowers that bloom several at a time from mid- July to mid-August • Pollinated only by the half black bumble bee, Bombus vagans • Average inflorescence produces 7 to 17 egg-shaped seed capsules • Seed capsules mature in late-September • Plant dies back with first frost • Plants are perennial; longevity up to 15 years; likely limited because of competition with other woody and herbaceous vegetation and periodic flooding and ice scour
Taxonomy and genetics The genus Pedicularis contains over 600 species, most of which are common in tundra, alpine, and subalpine floras in Asia, Europe and North America (Robart et al. 2015, p. 229). The center of Pedicularis species diversity is in the northern Himalayas, China, and Siberia. The Furbish’s lousewort has the most restricted distribution of any species of the genus Pedicularis (Gawler 1983, p. 28).
The Furbish’s lousewort (Pedicularis furbishiae Sereno Watson 1882) is a member of the broomrape family, Orobanchanceae (formerly from the snapdragon family Scrophulariaceae)(Olmstead et al. 2001). The taxonomic identity of the Furbish’s lousewort as a distinct species is unquestioned, but its taxonomic position within the genus Pedicularis is not certain (Macior pers. comm. in Stirrett 1980, p. 21) and has been a topic of considerable conjecture and discussion (Gawler 1983, pp. 28-29, Robart et al. 2015, p. 253).
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Dr. Peter Nelson at the University of Maine at Fort Kent and Rick Ree at the Field Museum in Chicago are continuing genetic research to identify the “sister species” and document the unique phylogeny of the Furbish lousewort. Dr. Nelson has collected samples at numerous subpopulations in Maine and New Brunswick to evaluate the genetic structure and variation within the Furbish’s lousewort metapopulation. Similar to the electrophoretic genetic results published by Waller et al. (1987, entire), preliminary results indicate low genetic variability in the Furbish’s lousewort population (P. Nelson email November 11, 2017). Additional results will be available in 2018.
2.2 Geographic Range and Habitat Description
Furbish’s lousewort is an endemic with narrow ecological requirements found only on the mainstem of the St. John River. It is found on portions of a 225 km (140 mile) section of the St. John River extending from a short distance upstream from the confluence of the St. John and Big Black Rivers in northern Maine (Township T14R14; USFWS 1991, Maine Natural Areas Program 2015, pp. 6-11) to the confluence of the Aroostook River, approximately 10 km north of Perth-Andover, New Brunswick (Environment Canada 2010, p. 1) (figure 3). In Canada, its range extends over the last 30 km of this section, beginning at the international border (approximately 5 km above the dam at Grand Falls) to approximately 10 km north of Perth- Andover, New Brunswick (Environment Canada 2010, p. 1).The lousewort is inextricably linked to the flood and ice dynamics of this single river, which flows north from its headwaters in northwestern Maine, then east, then south to the first dam at Grand Falls, New Brunswick (figure 2). The river carves through the boreal forests of northern Maine before widening into rich farmland of the middle and lower valley. It forms the boundary between Maine and New Brunswick, Canada for part of its northern reaches. The St. John River watershed is among the largest on the Atlantic seaboard and the river above Grand Falls, New Brunswick is the longest stretch of free-flowing river in the eastern United States (USFWS 1991).
Figure 2. Map depicting the range of the Furbish’s lousewort. 8
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The portion of the river basin incorporating the range of the Furbish’s lousewort is characterized by cool summers, a short growing season, and long, snowy winters. In downriver segments supporting Furbish’s lousewort (below Allagash, Maine) the river carves through thick deposits of glacial till and fluvial deposits with pockets of lacustrine silt-clay deposits, shorelines have a more gradual slope, and bedrock outcrops are relatively rare. Upriver reaches supporting Furbish’s lousewort have more rocky outcrops, tall, steeply-sloped riverbanks and less glacial and fluvial deposits. Groundwater seeps, many of which are extensive, occur periodically along the riverbank.
The St. John River in Maine is characterized by large and often rapid water level fluctuations. The few headwater lakes have little water storage capacity, causing the river to rapidly fluctuate in response to intense rainfall and seasonal snowmelt. At the Dickey gauging station, located in River Segment 2 of Furbish’s lousewort habitat (figure 5 p. 16), average monthly flows ranged from about 500 cubic feet per second (cfs) to more than 100,000 cfs, with high variability in late spring and summer flows. Because the river initially flows north, the southernmost reaches melt first and the flowing water then breaks up the ice in the more northerly, still-frozen reaches. Peak spring flows typically submerge all of the Furbish’s lousewort habitat annually. Ice jams are frequent but not annual events (i.e. occurring 7 of the last 10 years, 2008-2017, as recorded at the Dickey gauging station) (USGS 2018). There is no data that captures ice scour frequency or location. Anecdotal observations during census surveys suggest ice scour frequency is variable and some sections of riverbank are more commonly affected than others. .
Furbish’s lousewort habitat is generally confined to a narrow 2-meter band of ice-scoured, eroding riverbank below the forest edge and well above the rank herbs and grasses and cobble along the riverbed (Gawler et al. 1987, Gawler et al. 1987, p. 284). Lousewort plants are shade tolerant, but compete poorly with woody vegetation (alders Alnus spp.) and other dense vegetation. They are not found on the tributaries of the St. John River, including the Big Black, Allagash, and St. Francis Rivers, where low flows and reduced ice scour allow the development of dense vegetation to the water’s edge. Lousewort is mostly limited to the north- or west-facing riverbank shaded by the forest overstory. Some, generally small, isolated groups of plants are known to occur on the opposite riverbank under the shade of overhanging northern white cedar trees and in somewhat sunnier, south-facing sites in Canada. While reasons for this distribution are not completely known, cool, moist conditions and afternoon shade are believed to be important factors needed to support lousewort (USFWS 1991). The amount of solar exposure may be critical for seedlings as they are in greatest abundance where competing vegetation is relatively sparse allowing filtered light to reach the soil surface.
Furbish’s lousewort typically grows on gravelly, calcareous soils and on lacustrine or glacial till deposits but almost always in the presence of groundwater seepage (Menges 1990, p. 56). Most of the coarse glacial till soils along the river are low in nitrogen and organic matter and high in calcium (Malcior 1978b).
All plants have a climate envelope or niche outside of which they cannot survive (McKenney et al. 2007, entire). The summer maximum temperature that Furbish’s lousewort can withstand is unknown. The closest genetically related species to Furbish’s lousewort, P. bracteosa, P. ranierensis, and P. capitata are all alpine or arctic species that live in a cold, moist climate 9
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envelope (Tkach et al., 2014, entire). We deduce that Furbish’s lousewort also prefers a cool, moist, subboreal climate.
The St. John River is among the most ecological significant areas in Maine and supports more rare plants than anywhere else in the state (38 rare plant species; 3 state-endangered, 12 state- threatened, and 23 state-special concern species; Beginning With Habitat 2017). Many rare plant species live on the river bank in close association with the Furbish’s lousewort, including several state-listed species and regionally rare, disjunct species from western North America and the arctic (USFWS 1991, Table 2, p. 19). For example, the St. John tansy (Tanacetum bipinnatum ssp. huronense) lives only on the open cobble beaches along the river. Prairie rattlesnake root (Prenanthes racemosus) is found on the grassy shores that resemble a prairie habitat. The northern painted cup (Castilleja septentrionalis) only occurs on the St. John River, Mt. Katahdin, and a few alpine areas of New Hampshire and Vermont. In addition, there are several noteworthy natural communities, including Maine’s best examples of circumneutral riverside seeps and bluebell-balsam ragwort shoreline outcrops (Beginning With Habitat 2017). As a result, because of the numerous rare plants and natural communities associated with the Upper St. John River, protection efforts designed to conserve the Furbish’s lousewort have created long-standing and critical protection for an ecosystem of national significance.
2.3 Individual-level Ecology
The Furbish’s lousewort life history is summarized in the previous sections and table 1. The life stages require similar resources. Seeds must be deposited on cool, moist soil. A period of cold, winter temperature followed by spring temperatures above 60 degree F are needed before the seeds will germinate. Seedlings require a host plant, perhaps a nitrogen-fixing species, and a minimum of competition from other plants. Seedlings and young plants in the vegetative stage require optimal light conditions (filtered, not direct), an unknown amount of spring and summer precipitation, minimal competition, cool summer temperatures, and adequate soil moisture for a period of up to three or more years before they attain sufficient size to begin flowering. Flowering plants require the same key resources; cool, moist, but not saturated soils, minimal competition, filtered sunlight, cool summer temperatures, and an unknown amount of spring and summer precipitation. Flowering plants may be hemiparasitic and require a host plant. Furbish lousewort flowers are pollinated by a single bumble bee species, the half-black bumble bee Bombus vagans. A summary of individual resource needs is provided in table 2.
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Table 2. Resource needs by life stage. H = Habitat, N = Nutrition, R = Reproduction, D = Dispersal. Key resource needs are soil, precipitation, shaded or filtered sunlight, and limited competition.
Life stage Resource and/or circumstances needed for individuals Resource to complete life stage function (HNRC) Seed Moist soil / damp substrate H Perennial plant species to parasitize N Seedlings Periodic ice scour H Perennial plant species to parasitize N Low or minimal competition with herbaceous vegetation or woody H, N plants Moist soil / damp substrate H Vegetative Periodic ice scour H and Minimal competition with herbaceous vegetation and woody plants H, N Flowering Some amount of slope (not too flat) H plants Adjacent treeline/shade (proximity to forest edge) H Moist soil / damp substrate H Half-black bumble bee Bombus vagans for successful pollination R Resource needs obtained from Gawler 1983, entire and USFWS 1991, entire
2.4 Population-level Ecology
A population of an organism is a group of individuals within a geographic area that are capable of interbreeding or interacting. Although the term is conceptually simple, it may be difficult to determine the extent of a population of any species. The population of Furbish’s lousewort can best be described as a metapopulation; a group of spatially separated but interacting subpopulations of the same species (Charney and Record 2016, entire).
Population-level needs are an accumulation of the resource needs of individuals (table 2). Each individual mature plant reproduces, and germination occurs when the appropriate individual-level resource needs (i.e. soil, water, sunlight, and minimal plant competition) are met. Viable populations need a minimum number of individuals to germinate, survive, and replace individuals that have died or been lost to ice scour and erosion. For most species, we assess population-level resilience based on the number of individuals (i.e., abundance), colonization, recruitment, connectivity, and population growth. Because of the metapopulation structure of the lousewort population, we assume that connectivity of populations (primarily through cross-pollination by the half-black bumble bee) likely contributes to the genetic (representation) and demographic health and resilience of the population. We assume that the greater numbers of flowering and non-flowering individuals and greater number of subpopulations contribute to resilience and redundancy of the population.
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Population viability modeling was used to better understand how demographic variables (survival, growth, fecundity) affect the viability of the Furbish’s lousewort population (Menges 1990, entire). Menges (1990) gathered data in collaboration with Sue Gawler and Don Waller for the population viability analysis in the mid-1980s to evaluate the probability of survival of Furbish’s lousewort in the future. These data were collected during a period when the metapopulation was growing and approaching peak levels. Seven of 15 census units studied were increasing (lambda greater than one) (Menges 1990, page 56). However, even at that time extinction rates of subpopulations were greater than recolonization rates (Menges 1990, page 57). Annual extinction of subpopulations ranged from 2 to 12 percent whereas recolonization rates were about 3 percent. His population viability model predicted that with a 2 percent annual extinction rate, there was only a 13 percent probability that the Furbush’s lousewort would survive for 100 years (using 95 percent probability of survival for 100 years as the criterion of population viability) (Menges 1990, p. 57).
An estimate of a minimum viable population (MVP) has not yet been calculated for Furbish’s lousewort. However, we can establish at least one benchmark by comparing its known demography to a simple demographic model. Burgman et al. (2001, entire) developed MVP guidelines for rare plant populations by constructing a generic demographic model that reflected broad life-history traits for plants. Flowering, reproducing Furbish’s lousewort plants have an average survival rate of about 90 percent with a coefficient of variation of about 20 percent (Menges 1990, Table 7, p. 60). Applying Burgman’s model, a population of about 9,800 flowering Furbish’s lousewort plants would be necessary to achieve a probability of less than 0.1 percent of falling below 50 mature individuals at least once in the next 50 years (Burgman et al. 2001, Table 2, p. 606). Furbish’s lousewort has many of the life history characteristics identified by Burgman et al. (2001 p. 67, Table 3) that require a larger, rather than smaller MVP; restricted distribution, habitat specialist, restricted temporal niche, subject to extreme habitat fluctuations, genetic vulnerability, slow growth, a poor competitor, particular life stage vulnerable, long time to set first seed, not readily pollinated, variable seed production, low seed production and viability, short seed viability, seed affected by disturbance, poor dispersal, not able to coppice or resprout, and dependent on a host plant.
There are several consequences of low genetic diversity and representation in a plant population. The loss of genetic diversity may reduce the ability of a species or population to resist pathogens and parasites, to adapt to changing environmental conditions, or to colonize new habitats. Genetic drift may also result in the adaptation of an isolated population to the climates and soils of specific sites, leading to the development of distinct ecotypes and to speciation. We see no evidence of genetic drift within the small range of the Furbish’s lousewort.
2.5 Species-level Ecology
• In this section we describe the ecological requirement at the species level in the terms of the 3Rs. Species-level needs for Furbish’s lousewort are very similar to the resource needs at the individual and metapopulation levels (see table 2).
Viability is a measure of the ability to sustain populations over time. To have high viability, the Furbish’s lousewort needs a sufficient number of widely-distributed subpopulations to withstand
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episodes of environmental stochasticity (resiliency), catastrophes (redundancy), and changes in its environment (representation).
In figure 3, we depict what the Furbish’s lousewort needs to remain viable as a species. Like any species, to be highly resilient the lousewort needs a combination of populations that are composed of highly resilient individuals, such that the metapopulation has the ability to withstand stochastic events. For the Furbish’s lousewort to maintain high levels of redundancy, it needs a sufficient number of highly resilient individuals composing highly resilient populations to protect against major catastrophic events. For the species to maintain high levels of representation, it needs sufficient distinct variation in terms of genetic variability, ecological settings, morphology, and phenology. We lack information to quantify what levels of these factors are necessary for this species to maintain high levels of viability.
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Figure 3. A conceptual model summarizing the important population needs of Furbish’s lousewort. Additionally, this model incorporates stressors that may influence these resource needs, and thus affect the resiliency of Furbish’s lousewort. These stressors are discussed further in section 3.2 of this document, Summary of Factors Affecting the Species.
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3.0 Species Current Condition
In this chapter, we review the historical and current trends in species numbers, explain assumptions about the main drivers affecting population trends, and assess the various stressors that have influenced the species historically and currently.
3.1 Population Trends
The Furbish’s lousewort was first collected along the banks of the St. John River in Van Buren, Maine by Kate Furbish in 1880 (Furbish 1881). The first Canadian specimens were collected at Grand Falls, New Brunswick in 1878 and 1879 prior to Kate Furbish’s discovery (Stirrett 1980, p. 3), but they were incorrectly identified at the time, and their true identity was not discovered for many years.
Early accounts indicate that it was once more common in Canada than at present (Fowler 1885 in Environment Canada 2010, p. 3). Clearing of riparian forests for agriculture and the Grand Falls Dam in New Brunswick in 1928 undoubtedly caused declines or extirpation of some subpopulations. In 1975, the Smithsonian Institution listed the species as rare and probably extinct because it had not been collected in decades (Smithsonian Institution 1975). On June 27, 1976, the Furbish’s lousewort was “rediscovered” on the St. John River in Maine by University of Maine Professor of Botany Charles D. Richards (Richards 1977, entire) and shortly thereafter in New Brunswick, Canada by George. M. Stirrett (Stirrett 1980, p. 4) in surveys associated with the environmental assessment for the proposed Dickey-Lincoln hydroelectric dam.
Since its rediscovery in 1976, Furbish’s lousewort has been documented and surveyed in Maine at about 33 stations or census units along the St. John River from the most upriver site located at Blue Brook in T14 R14 to the most downriver site located at Hamlin Corners in Hamlin (Maine Natural Areas Program 2017, Figure 3). Most of the 33 census units in Maine were found by the early 1980s, but a few were added between 2005 and 2010. An additional five sites have been monitored in New Brunswick, Canada from above the Grand Falls Dam to the confluence of the Aroostook River (Furbish’s lousewort Canadian recovery team 2006, p. 1, M. Toner, email November 21, 2017).
Dr. Charles Richards (1977, entire) first documented the distribution of Furbish’s lousewort in 1976 and 1977. Dr. Richards conducted the first census of flowering stems in Maine and New Brunswick in 1980, which totaled 5,027 flowering stems (Richards 1980, entire). In 1981 and 1982, the Service hired the Maine Critical Areas Program to refine maps of the Furbish’s lousewort distribution and conduct a partial census of flowering stems to support conservation efforts (Gawler 1983, entire). Demographic data were collected from 1983 to 1986, which became the basis for a population viability analysis (Menges 1990, entire). In 1984, Eric Menges and Sue Gawler conducted the second complete census, and a few additional subpopulations were found (Gregory and Gawler 1990, pp. 1-2). During that census they counted 4,882 flowering stems. In 1989, Gregory and Gawler (1990, entire) mapped the rivershore for habitat suitability, and also completed a third census of flowering stems. Thereafter, the Maine Critical Areas Program, later renamed the Maine Natural Areas Program, standardized the Furbish’s lousewort survey by conducting a census of flowering stems every other year (Gregory and Gawler 1992, 15
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entire; Gawler and Gregory 1994, 1998, 1999; Gawler and Cameron 2001, Maine Natural Areas Program 2015, entire). This method was revised after 2001 such that half the census was completed in each year of a two year period (Maine Natural Areas Program 2015, entire). The change in method undoubtedly introduced error into the population estimates, but it could not be avoided, though it was expected that overall trends and conclusions would be little affected (Maine Natural Areas Program 2015, p. 4). Thus, 17 censuses have been completed from 1980 to 2017 (Appendix 2). The locations of subpopulations remained relatively static during this time period. Three new subpopulations were discovered upriver and one downriver from 2004-2009 (Maine Natural Areas Program 2015, p. 3). These subpopulations likely always existed, but these particular areas of the river had never been searched. These discoveries expanded the range of the lousewort further upriver. Extensive de novo surveys have been completed, and it is believed that all major subpopulations are now documented in Maine (Maine Natural Areas Program 2017), although it is always possible that small numbers of flowering plants could be found in new locations (D. Cameron, Maine Natural Areas Program, pers. comm. August 8, 2018). The five subpopulations in New Brunswick, Canada were surveyed or partially surveyed 18 times between 1977 and 2014 (M. Toner, email November 21, 2017). These data from Maine and New Brunswick are the basis for our analysis.
The census was based on counting flowering stems because it was not feasible to count all the Furbish’s lousewort plants at their various life stages. Non-flowering plants occur as small rosettes often mixed with other vegetation and can be difficult to find. There are likely multiple vegetative, non-flowering plants for each flowering plant, and each flowering plant may have multiple (1 to 15) flowering stems. Based on field observations, Gawler (1983, p. 29) assumed there was an average of 2.5 flowering stems per reproductive plant and twice as many total plants for each reproductive plant. Menges and Gawler (1986, pp. 9-10) documented an average of 1.4 flowering stems per reproductive plant and twice as many immature plants than flowering plants (Gawler et al. 1983, p. 8). These ratios vary between subpopulations and from year to year. For this reason, a count of flowering stems has been the most consistent method of censusing the breeding population and serves as a measure of lousewort population size.
In the most recent survey (2016-2017 in Maine and 2014 in New Brunswick (D. Cameron email November 21, 2017) the total population in the United States and Canada numbered about 2,398 flowering stems. Most of the population currently exists at locations upriver of St. Francis, Maine (83 percent), and downriver subpopulations have dwindled in recent years (Maine Natural Areas Program 2015, entire; Appendix 2). In the most recent census 9 subpopulations had more than 100 flowering stems, 7 subpopulations had 50 to 99 flowering stems, and 6 subpopulations had fewer than 50 flowering stems (Maine Natural Areas Program 2017, unpublished data).
The Furbish’s lousewort populations have fluctuated widely in the last 35 years (Maine Natural Areas Program 2015, entire, Appendix 2). Local extirpations sometimes occur because of habitat disturbance caused by ice scour or slumping and erosion of saturated, unstable banks (USFWS 1983, entire; Gawler 1981, entire; Gawler 1983, entire; Gregory and Gawler 1990, entire, Menges 1990, p. 59). Colonization of new sites has not been documented, and recolonization of locally extirpated subpopulations is rare (D. Cameron, Maine Natural Areas Program, personal communication, June 4, 2018). Given the frequency of ice-scour and flood disturbances on the river, subpopulation fluctuations have occurred and can be expected in the future.
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The Furbish’s lousewort occurs only where periodic ice scour is not too frequent or too uncommon, and where the appropriate host plants, moist soils, and the half-black bumble bee pollinator are present (Table 2). Ice scour frequency varies in amount and intensity throughout the range of the species. In 1990, Furbish’s lousewort habitat suitability was evaluated throughout the portion of its range in Maine between its upstream extent in town T14 R13 WELS and Fort Kent (Gregory and Gawler 1990, entire). At that time 11 mil of river was considered occupied and an additional 6.1 mil was considered to be potential habitat; that is, having characteristics of areas that typically support the species but having no plants (Gregory and Gawler 1990, entire; USFWS 1991, pp. 25-26). Combined together, the occupied and potential habitat made a total of 17.1 mil of suitable habitat. Between 1990 and 1998, Gawler revised and improved the habitat mapping and the resulting GIS shapefile included 20.4 mil of suitable habitat (Gawler 1998), a several mile increase over the original mapping. The 1998 habitat mapping shapefile was provided to the USFWS (Gawler 1998). In 2009, the MNAP (2009, entire) re-mapped and revised habitat suitability estimates and documented 22.8 mil of suitable habitat (table 3), but this includes 5.8 mil of suitable habitat mapped at newly discovered upstream sites. Summary results from the 2009 mapping update were that that suitable habitat upstream of Dickey Bridge declined only slightly in comparison to 1998 but was bolstered by newly discovered sites, and that suitable habitat downstream of Dickey Bridge declined by more than a third (36 percent). It is important to note that within suitable habitat areas, the plant occurs only where conditions are conducive for germination and plant growth (table 2), and that it is typically distributed in highly restricted patches that physically occupy only a small fraction of what surveyors consider to be suitable habitat (figure 4).
Figure 4. Figure of the Furbish lousewort subpopulations showing census data points in green.
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Table 3. Suitable habitat for the Furbish’s lousewort along a 225 km (140 mi) segment of the St. John River in Maine where the species occurs (Maine Natural Areas Program 2009,). River segments are the same as described in the Service’s Recovery Plan (USFWS 1991).
River segment Kilometers (miles) of Permanently Protected suitable habitat (percent) River Segment 1 (upriver) 28 km (17.4 miles) 7.7 km (4.8 miles)(28 percent) River Segment 2 (downriver) 6.4 km (4.0 miles) 2.1 km (1.3 miles)(62 percent) River Segment 3 (downriver) 1.8 km (1.1 miles) 0 River Segment 4 (downriver) 0.5 km (0.3 miles) 0 Total 36.7 km (22.8 miles) 9.8 km (6.1 miles)
Figure 5. River Segments as described in the Service’s Recovery Plan
Nearly four decades of Furbish’s lousewort census data from Maine and New Brunswick are summarized in figures 6 and 7. Key points concerning the Furbish’s lousewort populations are: • The Furbish’s lousewort occurs in a dynamic river environment and the metapopulation fluctuates in response to both localized and widespread ice-scour and flood events. The Maine population declined immediately following severe ice-scour events in 1989 and 2003 and after a series of smaller ice events between 1995 and2000 and in 2012 (figure 6). The metapopulation rebounded within 6 years following severe ice scour in 1989 and 2003. The metapopulation has not rebounded from the most recent, multiple ice scour events in 2012, and some sites formerly with plants appear incapable of supporting this species in the near term. (D. Cameron, Maine Natural Areas Program, personal communication August 6, 2018). • Both Maine (figure 6) and New Brunswick populations (figure 7) are at or near their low points since surveys began in 1980. The Maine population currently numbers 2,240 flowering
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stems, a 40-year low point. It is important to note that a significant portion of the flowering stems in the most recent 2016-2017 census (48 percent) are from newly-discovered, upriver sites that were not included in censuses prior to 2006. The contribution from the newly- discovered sites (one added in 2006-2007 and three added in 2008-2009) are making up for significant declines in other sites, many of which have historically supported much larger populations (Maine Natural Areas Program 2015, p. 5). • The most recent census (2018) of the New Brunswick population is 167 total plants and is also at a 40-year low point (figure 7). Populations in Canada remained relatively stable (394 to 531 plants) between 1977 and 1987. Canadian populations declined sharply in 1997 then rebounded to 758 (2002) and 904 (2003) total plants. Populations have since declined (M. Toner email dated August, 2018). • Every subpopulation censused over nearly four decades experienced significant population fluctuations, including instances of population growth, near extirpation, and local extirpations (appendix A). Recolonization of locally extirpated subpopulations is rare. • Since 1980, the peak counts of flowering stems after severe ice scour events have successively diminished (6,836 flowering stems in 1988-1989, 5,618 in 2002-2003, and 4,467 in 2010- 2011). In contrast, the low counts of flowering stems after severe ice scour events have remained relatively constant (2,021 flowering stems in 1992-1993; 2,105 in 2006-2007; and 2,240 in 2016-2017) (figure 6), although the most recent census includes 601 flowering stems from four subpopulations discovered since 2006. Both the peaks and low counts of flowering stems of the core census units surveyed since 1980 has declined (figure 5). • Overall, the Maine population has declined from 1980-2017. A regression of the flowering stems at core sites surveyed since 1980 indicates an average decline of about 2.2 percent per year. A regression of flowering stems at all sites surveyed since 1980 (including the four sites discovered since 2006) indicates an average decline of about 1.4 percent per year (figure 6).
There is a marked difference in the population status of upriver and downriver populations. From1980 to the present, the Furbish’s lousewort metapopulation has fluctuated with a downward trend (figure 8). Overall, upriver populations1 have decreased slightly (regression slope ≈ -0.6 percent per year) while downriver populations2 declined substantially (regression slope≈ -4.9 percent per year) (figure 8). In the 1980s, downriver populations made up nearly half the Maine population, whereas at present downriver populations make up only 12 percent of the population.
1 Subpopulations of Furbish’s lousewort in river segments 1 and 2 in the Furbish’s lousewort recovery plan. 2 Subpopulations of Furbish’s lousewort in river segments 3 and 4 in the Furbish’s lousewort recovery plan. 19
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Figure 6. Counts of flowering stems of the Furbish’s lousewort in Maine from 1980-2017 (Maine Natural Areas Program 2017; Don Cameron, Maine Natural Areas Program, unpublished data). The green lines represent the core populations tracked since 1980 and associated regression line. The red line represents all populations tracked since 1980 (including the four new sites discovered since 2006) and associated regression line. Canada plant totals 1977-2014 Furbish's lousewort 1000 900 800 700 600 500 Count of all plants
AxisTitle 400 core group of plants 300 200 100 0
Figure 7. Total counts (flowering and nonflowering plants) of the Furbish’s lousewort in New Brunswick, Canada from 1977-2014 (Furbish’s lousewort Canadian recovery team 2006, p. 1; M. Toner, email November 21, 2017). Data from 2018 found 167 plants (M. Toner, email August 2018).
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5000
4500
4000
3500
3000 Upriver populations (river 2500 segments 1 and 2)
2000 Downriver populations (river segments 3 and 4 1500
1000
500
0 Year 1980 1984 1989 1991 1993 1995 1997 1999 2001 2003 2005 2007 2009 2011 2013 2015
Figure 8. Counts of flowering stems of the Furbish’s lousewort in Maine from 1980 to2017 and associated regression lines in upriver segments (red) and downriver segments (green)(Maine Natural Areas Program 2017; Don Cameron, Maine Natural Areas Program, unpublished data).
3.2 Factors Affecting the Species Current Condition
When the Furbish’s lousewort was federally listed in 1978, the primary threats were loss of habitat (listing factor 1: the present or threatened destruction, modification, or curtailment of its habitat or range) because of “modifications by farming and construction, dumping, natural landslides, and construction and lumbering near the banks of the river.” In addition, about 40 percent of the metapopulation occurred within the proposed impoundment area of the Dickey- Lincoln School Lakes Project (43 FR 17915). By the time recovery plans were developed in 1983 and 1991, the same threats were still considered relevant (USFWS 1991, pp. 27-29). Congress deauthorized the Dickey-Lincoln School Lakes Project on November 17, 1986, removing the greatest, most immediate threat to the species. Additional stressors not known or considered at the time of listing but documented in the Service’s 5-year review (USFWS 2007, pp. 8-11) include nonnative invasive plants and the effects of climate variability and climate change on the ice dynamics of the St. John River.
At the time of this assessment, the stressors most likely to affect the viability of Furbish’s lousewort are (1) development that causes habitat loss, erosion, and fragmentation and (2) climate change that causes the current trends of warmer winters that affect the ice dynamics, flooding, and the overall disturbance regime of the St. John River. The current effects of these stressors on Furbish’s lousewort are incorporated into the current condition of the species, especially in our evaluation of population Resiliency (section 3.3.1) and Redundancy (section 3.3.2) below. The 21
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low genetic variability in Furbish’s lousewort is discussed in section 3.3.3 Representation of this assessment.
3.2.1 Development
Historic land use patterns influence Furbish’s lousewort habitat today; the land use upriver of the town of Allagash is undeveloped, and owned by four forest management landowners, while downriver landscapes in Maine and further downriver in New Brunswick are dominated by agriculture and small villages.
Comprehensive land use plans in Maine provide a useful perspective concerning the status of population trends, land use and housing development in the St. John River valley. The St. John River valley is located in northern Maine in a rural landscape with widely scattered towns and villages, the largest being Fort Kent (population ~4,000). The population in the St. John River valley has been declining. For example, over the 30-year period (three Federal Census periods) from 1980 to 2010, the population of Fort Kent, Maine lost 11.6, 7.5, and 3.5 percent of their population (Town of Fort Kent 2012, pp. 49-50). Other towns along the St. John River also lost population in the 2000-2010 period; St. Francis -15 percent, St. John -5 percent, and Van Buren - 19 percent (Town of Fort Kent 2012, p. 50). Populations are projected to remain stable through 2023 (Town of Fort Kent 2012, p. 51). In Fort Kent, a service center for the region, there were 10 to 19 single-family housing starts per year between 2006 and 2011 (Town of Fort Kent 2012, p. 77-78), most of which occurred in new housing subdivisions in former agricultural fields because these are the most inexpensive to develop (Town of Fort Kent 2012, pp. 152-153). Some of these subdivisions are located along the river near Furbish’s lousewort habitat. Development in other small municipalities located downriver is less pronounced, and agriculture remains the primary land use in the river valley. There is no development in unorganized towns upriver of the town of Allagash.
Similar trends occur in downriver areas in New Brunswick. A threats assessment was completed in New Brunswick by evaluating aerial photographs along the St. John River from 1944-1996 and conducting a survey of the riverbanks (Nature Trust of New Brunswick 2005, entire; Furbish’s lousewort recovery team 2006, pp. 15-18). Boating activities (docks), bank stabilization projects, commercial development, gravel pits, riparian forest clearing, residential development, illegal dumping and fill along the riverbank, and recreational activities (footpaths, marinas, picnic or other access areas) have all increased, whereas, agriculture and roads along the river decreased (Nature Trust of New Brunswick 2005, entire). About 42 percent of the river shoreline had threats to rare plant habitats that could be categorized (Nature Trust of New Brunswick 2005, pp. 11-12). Roads and recreational use were the most widespread threats posed by land use activities, but gravel pits that were not buffered posed the most damaging effects to shoreline habitats (Nature Trust of New Brunswick 2005, p. 13).
Changes in land use on the banks of the St. John River in downriver areas have occurred through the clearing of vegetation, especially trees, for agriculture, individual house lots, roads, and river views. These land use changes within the St. John River valley may have negatively affected some of Furbish’s lousewort subpopulations’ habitat through removal or reduction of the forested riparian buffer and subsequent loss of shade critical to lousewort growth and reproduction. Areas cleared of forest and impermeable surfaces associated with development have led to erosion and 22
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subsidence of the unconsolidated glacial till soils, and caused slumping and erosion of Furbish’s lousewort habitat. We will evaluate development as a stressor further in our assessment of future scenarios.
3.2.2 Climate Change
We use our expert judgment to evaluate relevant information, including uncertainty, in our consideration of various aspects of climate change. In general, it is anticipated that plant species with restricted ranges may experience population declines as a result of climate change. The Intergovernmental Panel on Climate Change (IPCC) Climate Change 2014 Synthesis Report states, “most plant species cannot naturally shift their geographical ranges sufficiently fast to keep up with current and high projected rates of climate change on most landscapes” (IPCC 2014, p. 13). However, areas containing endemics may also provide stable climatic refugia into the future, as evidenced by past climate variations (Harrison and Noss 2017, p. 207).
Maine climate conditions and projections are summarized in Jacobson et al. (2009) and Fernandez et al. (2015). Briefly, average annual temperatures were stable in northern Maine since 1900 until about 1980, when a significant increase of about 1.50 F occurred (Jacobson et al. 2009, Figure 7, p. 13). The hydrological cycle has changed significantly over the last century in Maine (Jacobson et al. 2009, figure 8, p. 13). Northern Maine shows a negative trend in annual precipitation since 1900, but has trended toward wetter conditions from 1950-2007. Climate change is affecting temperature, snow, and precipitation patterns in the Northeast at rates faster than expected (Rustad et al. 2012, p. 6). Rapid winter warming in recent decades is believed to be influenced by an albedo effect caused by the reduced persistence of snow in winter (Hayhoe et al. 2006). Average winter temperatures are increasing 0.42° - 0.46°C/decade (0.76° - 0.83 °F/decade) with the greatest warming occurring in the winter months, especially January and February (Burakowski et al. 2008, Jacobson et al. 2009, p. 15). Projections for the future show greater increases in winter temperatures and precipitation in northern Maine than for other seasons and regions of the state (Jacobson et al. 2009, figure 9, p. 15; Fernandez et al. 2015, p. 3). Under mid- to high-emissions scenarios, average mean temperatures in northern Maine are projected to increase by 6.7° - 7.8°C (12° - 14°F) by 2080-2099 relative to 1971-2000 (Manomet Center for Conservation Sciences and National Wildlife Federation 2013, p. 43). The number of winter days below freezing will decrease in the Northeast by about 20 to 30 percent (Manomet Center for Conservation Sciences and National Wildlife Federation. 2013, p. 63). Under a higher emissions scenario, snow covered days in northern Maine (from December to February) could decrease from 30 days per month observed from 1961-1990 to about 18-20 days per month in 2070-2099 (Manomet Center for Conservation Sciences and National Wildlife Federation 2013, p. 49).
The Furbish’s lousewort is identified as one of Maine’s plant species most vulnerable to climate change (Jacobson et al. 2009, p. 33). The species depends on periodic disturbance of the riverbank from ice scour; not too frequent or too infrequent and not too severe (section 2.4). Climate change is expected to affect the ice regime of northern rivers, including the St. John, by increasing the frequency and severity of severe ice-scour and flood events (Beltaos 1997, entire; Beltaos and Prowse 2001, entire; Beltaos and Prowse 2009, entire).
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Ice jams and flooding on the St. John River damage human property, and considerable effort has been made to develop numerical river ice models for the St. John River to better forecast and analyze ice-jam related flood events (Beltaos and Burrell 2002, entire; Beltaos et al. 2003, entire; Tang and Beltaos 2008, entire; Beltaos and Prowse 2009, entire; Kim and Jain 2015, entire). Changes in recent ice behavior and projections of future climate conditions indicate that the duration, composition and extent of river ice is changing (Beltaos and Prowse 2009, entire). Mid- winter jams often freeze in place when the cold weather resumes [in reference to periods of mild mid-winter temperatures on northern rivers]. Freezeup levels are then higher than normal, and icecover thicknesses greater. These two factors can lead to extreme jamming in the spring if the freshet happens to generate unusually large flows. (Beltaos and Prowse 2009, p. 138). Alternately, river ice at the more southerly extremes can break up under warmer mid-winter temperatures and rain, move northward, and reconsolidate under colder temperatures. Such reconsolidated ice jams may increase the severity of spring ice jams on the St. John River (Beltaos et al. 2003, p. 78). More frequent occurrences of mid-winter breakup and associated jamming is a major effect of climate change that can be predicted with some confidence (Beltaos and Prowse 2009, p. 137). For long rivers like the St. John that flow northward (in Maine), differential rates of warming along their lengths can modify the severity of breakup.
Peak winter flows have increased substantially on the St. John River as a result of increased, mid- winter rainfall (Beltaos 2002, entire) caused by a marked increase in the incidence of mild (mean daily air temperatures above >00 C) winter days. Small perturbations in winter temperature can produce major changes in the incidence of breakup and ice jams, by altering snowstorms into rainfall events (Beltaos 2002, p. 789). Increasing winter flows are concurrent with a modest rise of the average monthly temperatures during the winter (Figures 9). Flows associated with winter runoff events in the Saint John River can be large enough to initiate breakup, but have not attained magnitudes that cause major ice-jam flooding. The main risk posed by such events at present is indirect: any ice jams that form during a winter event produce higher freeze-up levels and thicker ice covers when the cold weather resumes. These factors enhance the potential severity of the spring breakup and the increased severity of flooding (Beltaos 2002, pg. 802; Beltaos and Prowse 2009, p.134).
River ice models for the St. John River demonstrate that the key variables influencing the frequency and severity of ice scour, jamming, and flooding are the incidence of midwinter temperatures above freezing, midwinter precipitation in the form of rain, and increasing river flows (Beltaos and Prowse 2009, p.134-137), all of which are increasing (Kim and Jain 2015, entire). Beltaos (2002, entire) did a hydroclimatic analysis for the upper St. John River using long-term climate and flow records. He documented that a small rise in winter air temperatures over the past 80 years has resulted in a substantial increase in the number of mild winter days and the amount of winter rainfall, which were previously rare occurrences in this region. These two factors augment river flows, causing increased breakup of ice cover, increased peak flows in late winter, and cause a greater frequency of spring ice jams and flooding.
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Figure 9. Median winter temperatures are stable but the number of warm days above freezing are increasing in the St. John River watershed. High floods and ice jams are increasing on the St. John River (data assembled and analyzed by Kim and Jain 2015, Figure 2, p. 4). The gray box plots (bottom of the graph) show mean, variance, and range of January-February temperatures. The black dotted line shows median mid-winter temperatures remain stable from 1948-2007. The solid black line shows the smoothed non-linear trend. However, the warmest midwinter temperatures showed an increasing trend (shown in red). The red dotted line represents the linear trend and the solid red line is smoothed non-linear trend. There are no trends in warmer winter days up to 1980. However, there is clearly an upward trend in above-freezing midwinter temperatures in the last 30 years (Kim and Jain 2015). Warm winter temperatures increase flow rates and the frequency and severity of ice scour events on the St. John River (Beltaos and Prowse 2009, p.134-137)
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Figure 10. Beltaos (2018 unpublished) observed a similar trend in mild days (>00 C) during January and February (1920-2015). Each data point represents average value over a five-year period and is plotted on the middle year of the period. The most recent data point describes the interval 2011-2015
Figure 11. Both the average midwinter flows and maximum winter flows are increasing on the St. John River because of warmer winter temperatures (data assembled and analyzed by Kim and Jain 2015, Figure 1, p. 3). The average midwinter flow is depicted by the gray box plots (bottom of the graph) that show mean, variance, and range of January-February flows 1930-2007. The black dotted line depicts a linear increase in mid-winter river flows 1930-2007, whereas the solid black line shows the smoothed non-linear trend. The maximum winter flow is depicted by the gray shaded rectangles (top of the graph). The red dotted line shows a linear increase in mid- winter maximum flows, whereas the solid red line shows the smoothed non-linear trend.
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Increasing summer temperatures may also affect Furbish’s lousewort. The climate envelope of Furbish’s lousewort has not been described, but its closest genetic relatives are all arctic plants that require cool, moist environments (Section 2.2). We are uncertain about the maximum summer temperatures and moisture deficits that Furbish’s lousewort can withstand.
In summary, there is evidence suggesting that climate change is indirectly affecting the ice dynamics of the St. John River and these factors have the potential to increase the severity of the spring breakup and increased severity of flooding (Beltaos 2002, entire).We will evaluate climate change as a stressor further in our assessment of future scenarios.
3.2.3 Consideration of other stressors
In 1978 in the final listing rule, the Dickey-Lincoln School hydropower project was identified as the primary threat to the species in the United States. The dams would have impounded an area of about 88,000 acres upriver of Allagash and would have eliminated all of the upriver Furbish’s lousewort populations (43 FR 17910, Manning 1973, pp. 6-13). It was de-authorized by Congress in 1986 (U. S. Fish and Wildlife Service 1991) and no longer is a foreseeable threat.
The Grand Falls Dam was built in Grand Falls, New Brunswick in 1928. It has a 40-foot head, 66-megawatt capacity, and impounds water on the St. John River to about Van Buren, Maine. The dam likely flooded Furbish’s lousewort habitat in Maine and New Brunswick. The dam impounds the river to about Van Buren, Maine, which includes lousewort populations at the Van Buren, Hamlin, and Hamlin Corners. The Van Buren and Hamlin populations are currently extirpated and the Hamlin Corners population declined slightly since it was discovered in 2009. One small, fragmented population persists within the impounded area above the dam in New Brunswick (Environment Canada 2010).
The ice scour regime is likely reduced in the impounded area of the Grand Falls Dam. Furbish’s lousewort habitat is very different within the impounded area with little evidence of a wide ice scour zone, and the forest grows nearly to the river edge. There is evidence of slight ice scour that maintains a narrow, disturbed band along the riverbank just above the waterline.
There are no new hydroelectric dams currently proposed on the St. John River in the United States or Canada. However, New Brunswick Power announced in 2017 that it was exploring the possibility of more than doubling the generation capacity at the Grand Falls Dam with the addition of a 100-megawatt generating station (https://www.nbpower.com/en/about-us/news- media-centre/news/2017/nb-power-exploring-potential-for-second-hydro-station-at-grand-falls/ last accessed July 30, 2018). We are uncertain of the proposed project details, status, and timeline and whether increased generation capacity could affect lousewort habitat and populations in New Brunswick and Maine. Because of the uncertain nature of this project, we do not evaluate it as a stressor in the future.
Additional natural factors, such as herbivory by snowshoe hares (Lepus americanus) (Menges et al. 1986) and seed parasitism by the plume moth (Amblyptilia pica) (Menges et al. 1986, pp. 1168,1172-1173; Macior 1978, Macior 1979 in Stirrett 1980) are known to occur, though the long-term effects on the overall population are not quantifiable at this time. A study completed in 27
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1986 reported that about 40 percent of flowers are lost from herbivory, primarily from snowshoe hares, but also whitetailed deer Odocoileus virginainus), and perhaps rodents (Menges et al. 1986, p. 1174). In addition, 39 percent of seed capsules contained plume moth caterpillars that destroyed or reduced the viable seeds (Menges et al. 1986, p. 1173). As expected, the amount of herbivory and seed predation varies between sites and years. These results led Menges et al. 1986 (p. 1175) to “hypothesize that losses of seed to various agents are important factors in limiting lousewort population sizes and population growth.” No additional or recent studies on herbirvory or seed predation are available since this study was completed. Therefore, no further evaluation of this stressor will be assessed.
Finally, we acknowledge the potential overall decline in pollinating bumble bees in general (Cameron et al. 2011, entire). The abundance of the half-black bumble bee is unknown in Maine, however its populations have declined elsewhere in its range in Ontario and Illinois (Colla and Packer 2008, p. 1384-1385, Grixti et al. 2009, pp. 81-82, Williams et al. 2009, p. 4). The half- black bumblebee is currently widely distributed throughout Aroostook County (Maine Bumble Bee Atlas, https://mainebumblebeeatlas.umf.maine.edu/me-bumble-bees/distribution-by-town/ last accessed July 13, 2018). No further evaluation of this stressor will be assessed.
3.2.5 Conservation Actions Several conservation actions, described below, are in place, and may reduce some of the stressors to Furbish’s lousewort and or provide habitat protection.
Shoreland zoning - Maine Furbish’s lousewort habitat receives some protection from State and municipal regulations. Riparian habitat upriver of the town of Allagash in unorganized townships is regulated by the Land Use Planning Commission (LUPC). The LUPC also regulates shorefront downriver in the towns of St. John Plantation and Hamlin where lousewort occurs. Furbish’s lousewort habitat in organized towns is regulated by mandatory shoreland zoning. The organized towns from Allagash and downriver adopted the minimum requirements regulated by the shoreline zoning. More information on zoning regulations in Furbish’s lousewort habitat can be found in Appendix 1.
Municipal Shoreland Zoning exists in the organized towns and provides only partial protection of lousewort habitat. Zoning prohibits "clearcut" openings in the first 100 feet from the high water line, but allows removal of up to 40 percent of the volume of trees to the river edge within a 10- year period. The shoreland zone extends to 250 feet from high water on the St. John River, but is less restrictive at greater distances from the river. Agriculture requires a 75-foot setback, and new buildings, roads, and gravel mining require a 100-foot setback. Organized towns have the option to designate lousewort habitats as resource protection subdistricts, which would provide more stringent measures. For example, in resource protection districts there is no cutting of vegetation within a 75-foot buffer, there are limitations of the footprint size of residential development and mineral extraction, and there is no new commercial or industrial development. At this time, no towns have designated resource protection subdistricts for the Furbish lousewort.
Vegetation clearing and forestry regulations in the shoreland zone along the St. John River are similar in unorganized townships upriver of the town of Allagash and the towns of St. John Plantation and Hamlin downriver of Allagash. Trees can be harvested to the river edge, but there 28
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is no clearcutting, and the forest within 50 feet of the river must retain a natural condition. Forest roads can be placed in the shoreland zone, and the size of cuts within 250 feet of the river is restricted. In both organized and unorganized townships, 40 percent of the total volume of trees may be harvested in a 10-year period.
St. John River Resource Protection Plan The exceptional natural resource and recreational values associated with the St. John River have warranted special voluntary protection of this area since 1979. Industrial forest landowners voluntarily signed the St. John River Resource Protection Plan (SJRRPP) beginning in 1982 with revisions in 1992, 2002, and 2012 (Land Use Planning Commission 2012, entire). Given the voluntary nature of the plan, one of Maine’s largest landowners decided the plan was no longer in their best interest and did not sign on during the 2012 review. The intent of the SJRRPP is to protect the natural values and traditional recreational uses of the river. The primary value of the plan to the conservation of Furbish’s lousewort is that it does not allow commercial and residential development, subdivisions, water impoundments (dams), and utility projects. The Maine Land Use Planning Commission monitors the SJRRPP in consultation with other state agencies such as the Maine Natural Areas Program. Forest management is allowed in the 250- foot resource protection buffer along the river, but is subject to numerous constraints similar to those imposed by LUPC elsewhere in unorganized townships (Land Use Planning Commission 2012, Table 4, pp. 9-15).
Shoreland protection – New Brunswick The New Brunswick Department of Environmental and Local Government acts as the regulatory entity responsible for issuing all watercourse alteration permits. The Watercourse Alteration Regulation is implemented under the New Brunswick Clean Water Act. The Technical Guidelines for implementing these regulations specify that no heavy equipment may be operated within 15 meters of the bank of a watercourse, no ground disturbance may occur within 30 meters of a watercourse, and only 30 percent of the total merchantable trees may be removed from a 30 meter buffer zone every 10 years. All activities taking place within 30 meters of a watercourse that is either one hectare or larger in area or involves the removal, deposit or disturbance of the water, soil, or vegetation requires a permit (Province of New Brunswick 2012, pp.11-12, 75-78). The Nature Trust of Canada is developing the Upper St. John River Habitat Conservation Strategy; a conservation plan (http://www.naturetrust.nb.ca/wp/blog/upper-st-john-river-usjr/ last accessed July 11, 2018).
Permanent habitat protection Several parcels that support Furbish’s lousewort have permanent habitat protection. • Since 2001, the New England Forestry Foundation has held a 754,673-acre conservation easement (the Pingree Forest Partnership) on lands along the St. John River where the Furbish’s lousewort occurs. (http://www.sevenislands.com/page/2-653/easement last accessed July 13, 2018). The easement protects the property forever through restricting development rights. Terms of this easement include a 1000-foot wide river buffer within this area that precludes timber harvest along the St. John River in the towns of T15 R13 WELS, T16 R13 WELS, and T16 R12 WELS. This protects about 6.2 percent of the current Maine population. • The Maine Bureau of Parks and Lands (MBPL) owns a large unit in the town of Allagash, that provides several hundred feet of Furbish’s lousewort habitat. About 1.0 of 2.6 river 29
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miles (38 percent) of the subpopulation located at St. Paul's Church downriver, Allagash Delta, Pelletier Brook, Casey Brook - Cross Rock, and Allagash is owned by the Maine Bureau of Parks and Lands (MBPL) in the town of Allagash. In 2017, The MBPL began to develop a 15-year management plan for approximately 63,000 acres of lands known as the St. John Uplands Region. The MBPL Integrated Resource Policy requires that it promote the conservation of Federally-listed species (https://www.maine.gov/dacf/parks/publications_maps/docs/irp.pdf last accessed July 30, 2018). A regional planning process is pending for the public lands in this region, but it has been postponed and it is not clear when it will occur. This protects about 2 percent of the current, total Maine population. • One of the five subpopulations in New Brunswick is permanently protected. The George M. Stirrett Preserve, established in 1992 by the Nature Trust of New Brunswick with purchased lands protects a subpopulation that once contained several hundred plants. As of summer 2018, a single flowering plant was recorded.
Census and surveys Since listing in 1978, the Service has provided funding to the MNAP to survey Furbish’s lousewort populations (section 3.1). In addition, in recent years the MNAP has mapped potential habitat along relevant areas of the St. John River in Maine, developed a database of landowners, and recorded the extent and number of erosion events. Landowners are contacted for survey access every other year, which offers and opportunity for outreach. The MNAP has worked closely with TNC and the Service to conserve the unique biodiversity of the St. John River.
Land Trusts The Upper St. John Land Trust is located in Fort Kent, Maine. It is a small land trust with limited capacity. They own four parcels that total 43 acres. Although they have expressed interest in conserving lousewort habitat, they have not been successful or active in recent years. Surveys conducted by the land trust indicate over 50 percent of landowners with Furbish’s lousewort habitat in the lower reaches of the river are interested in conservation easements or fee title acquisition. A region wide organization was established several years ago, the Upper St. John River Organization, with very broad goals for natural resource protection and sustainable development in northern-most Maine(http://www.upperstjohnriver.org/ last accessed July 30, 2018).
State and federal review of projects The MNAP reviews forest management plans submitted to the Maine Forest Service. They also review projects that require state environmental review and permitting from the Maine Department of Environmental Protection and Maine Department of Transportation projects that intersect with or are near significant botanical features. Since 2009, the Service reviewed nine projects with a federal nexus that concerned Furbish’s lousewort. These projects addressed road construction, U. S. Borders and Customs facilities, and a powerline right-of-way.
Habitat restoration Since 2009, the Service Partners for Fish and Wildlife program has worked with Steve Young, a small business owner in Aroostook County, to restore riparian forest potential habitat for the Furbish’s lousewort. The vision has been to develop partnerships with willing landowners, conduct habitat assessment surveys, and plant native woody trees/shrubs to stabilize eroding river 30
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banks in the downriver segments. So far, $110,000 has been invested ($40,000 in-kind) and trees were planted along 4.6 miles of river creating 55.2 acres of forested riparian habitat. Thirty-seven landowners encompassing 40 parcels participated in the program. The Partners program has continued a legacy of cooperative landowner relations initiated by the MNAP in the 1980s. More than half of the landowners participating in the Partners tree planting program expressed an interest in conservation easements on their property.
Outreach In addition to periodic landowner contact for survey access, in 2003, the MNAP published and distributed A Landowners Guide to the Conservation of Furbish’s Lousewort and the St. John River (Maine Natural Areas Program 2003). About the same time, landowners were contacted to provide information and determine their interest in options for permanently protecting lousewort habitat along the riverbank.
3.3 Assessment of Current Conditions
3.3.1 Analytical Approach
Delineation of Populations Furbish’s lousewort functions as a metapopulation. Unlike a continuous population, a metapopulation has spatially discrete local populations or subpopulations, in which migration between subpopulations is significantly restricted. For the purposes of this SSA, we defined subpopulations of Furbish’s lousewort as separated by a mile or more of unsuitable habitat based primarily on the limitations of its pollinator, the half-black bumblebee. Studies of Bombus species typically exhibit foraging distances of less than 1 km (0.62 mi) from their nesting sites (Knight et al. 2005, p. 1816; Wolf and Moritz 2008, p. 422; Dramstad 1996, pp. 163-182; Osborne et al. 1999, pp. 524-526; Rao and Strange 2012, pp. 909-911). For the purposes of this SSA, based on this criterion we identified 15 subpopulations of the Furbish’s lousewort in Maine and 5 in New Brunswick, Canada that form the basis for our analysis.
Figure 12. A map identifying the location of the 15 subpopulations of the Furbish lousewort in Maine and 5 in New Brunswick, Canada.
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Analysis of Population and Habitat Conditions In this SSA report, we utilize the best available scientific data to assess the current condition of each subpopulation as Good, Fair, or Poor based on our assessment of how well the needs of the subpopulation are being met, as detailed here. We evaluated each subpopulation according to three population attributes; abundance, density, and current status of the subpopulation compared to the site history (table 4). Sites where lousewort is currently absent (locally extirpated) were designated Very Poor. We evaluated each subpopulation according to three habitat criteria; the amount of potential habitat, the condition of the forested riparian buffer, and the prevalence of erosion events (table 4). These habitat factors were selected to describe habitat quality because of their influence on the Furbish’s lousewort as described in sections as 2.3, 2.4, and 2.5 of this SSA. Population and habitat metrics for the Maine sites were provided by the Maine Natural Areas Program (Maine Natural Areas Program 2017, entire; D. Cameron, Maine Natural Areas Program, GIS unpublished data). Similar habitat data were not available for all sites in New Brunswick. Canadian biologists used the criteria and their best professional judgement to assess their habitat conditions. For each site, a score of 3 (Good), 2 (Fair), 1 (Poor), or 0 (Very Poor) was assigned for each population and habitat criterion.
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Table 4. Summary of site-level population and analysis criteria. Population Analysis Criteria Score Abundance Density Current status 3 (Good) Current population Number of flowering Currently within top greater than 440 stems/mile of quartile of population flowering stems potential habitat > counts (75%) 140 flowering stems/mile 2 (Fair) Current population is Number of flowering Currently within 38 to 440 flowering stems/mile is 60/mile middle quartile of stems to 139/mile population counts (25- 75%) 1 (Poor) Current population less Number of flowering Currently within the than 38 flowering stems/mile of lower quartile (25%) stems potential habitat is of population counts 10/mile to 59/mile 0 (Very Poor) Lousewort no longer 0 flowering present stems/mile
Habitat Quality Analysis Criteria Score Length of mapped Buffer rank Number of erosion potential habitat events per linear mile of mapped potential habitat 3 (Good) 2 miles or greater Well buffered, far 0 events/mile exceeding 250 feet 2 (Fair) 0.5 miles to 2 miles Buffer 250 feet or Between 0 events/mile greater throughout and 3 events/mile >75% of river segment 1 (Poor) <0.5 miles <75% of the river > 3 events/mile segment with 250 feet buffer; narrow treeline; or no riparian forest
The overall current condition for each subpopulation is determined as an average of the six individual criteria. There was no weighting of criteria, so each population and habitat criterion had equal weight.
3.3.2 Results
Populations Results of the current condition for the 20 subpopulations (15 in Maine, 5 in New Brunswick) of Furbish’s lousewort are presented in Table 5. Subpopulations are arranged from upriver to downriver and according to river segments in the Service’s recovery plan (blue=River Segment 1, red=River Segment 2, green=River Segment 3, purple=River Segment 4, and orange=New
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Brunswick, Canada subpopulations) (USFWS 1991, p. 7). The results of the assessment of current condition of subpopulations and their habitats for Maine are two subpopulations are in good condition, two are in fair to good condition, three are in fair condition, and eight are in poor condition. In New Brunswick, all subpopulations are in poor condition.
The current size of the Maine population from the 2016-2017 census was estimated at 2,240 flowering stems (Maine Natural Areas Program 2017, entire), which represents about 896 to 1600 adult, reproductive plants (based on 1.4 to 2.5 average flowering stems/reproductive plant; Menges and Gawler (1986, pp. 9-10), Gawler (1983, p. 29)). The current population of all plants (vegetative and reproductive) in New Brunswick in 2018 was about 167 plants (M. Toner, Species at Risk, New Brunswick, unpublished data).
In Maine, Furbish’s lousewort is currently present in 9 subpopulations and absent from 6 subpopulations. In New Brunswick it is present in all 5 subpopulations. Overall, the metapopulation is at or near all-time low counts in both Maine and New Brunswick (Section 3.1). The reasons for the most recent population declines may be increased erosion and habitat loss and smaller, but more frequent ice scour events (D. Cameron, Maine Natural Areas Program, personal communication June 21, 2017). Declines in the Canadian subpopulation at Stirret Preserve relate to soil erosion and overshading at the Aroostook site (G. Forbes, pers. Comm 2018). Previous population declines in 1989 and 2003 were caused by well-documented large-scale ice scour events (D. Cameron, Maine Natural Areas Program, personal communication June 21, 2017, Section 3.1).
There is a distinct difference in the status of upriver subpopulations (River Segment 1 above Dickey Bridge in Allagash) and downriver subpopulations. Upriver subpopulations occupy longer stretches of riverbank and are more contiguous. Downriver subpopulations (River Segments 2, 3, and 4 - below Dickey Bridge), including those in New Brunswick, are restricted to smaller stretches of riverbank and are more widely dispersed.
Habitat There is also a marked difference in habitat located upriver of Allagash, Maine and downriver of this location. Upriver subpopulations occur in a landscape dominated almost exclusively by actively managed forests. The largest amounts of suitable habitat occur in this upriver portion of the species’ range. Riparian buffers are intact (at least 250 feet) at most upriver sites, and although ice scour of lousewort habitat is frequent, erosion and slumping of large sections of shoreline are rare. Of the six upriver subpopulations, only one has a portion (~61 percent) permanently protected via a conservation easement held by the New England Forestry Foundation (section 3.2.5). Downriver segments, including those in New Brunswick, are in a landscape dominated by agriculture and riverfront development. Habitat quality at three subpopulations in Maine and one in New Brunswick are influenced by the Grand Falls Dam (Section 3.2.2) that flooded lousewort habitat and reduced the ice scour regime. In downriver areas, potential habitat areas are much smaller (generally less than one mile of contiguous habitat). Forested riparian habitat is compromised to some degree at most downriver sites (except Hamlin Corners). Erosion and slumping of shoreline habitat is more prevalent in downriver areas. One of the nine downriver subpopulations in Maine is partially (~38 percent) protected, and one of the five subpopulations in New Brunswick is entirely permanently protected, but contains a single plant as of 2018. 34
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Table 5. Summary of current condition of Furbish’s lousewort. Subpopulation Landowner Protection status Abundance Density Current status Length of Riparian Number of Current (flowering (plants/mi.) within the site mapped buffer erosion condition stems – potential events/mile Maine, total habitat plants Canada Blue Brook Downstream, Irving, St. John R. plan, 362 161/mi. Middle quartile 2.25 mi. >250 ft. 0/mi. 2.7 T13/T14 Townline, Basford Orion, (Prentiss Carlisle 2 Fair 3 Good 2 Fair 3 Good 3 Good 3 Good Good Rips Upstream Prentis & no longer in Plan) Carlisle LUPC
Basford Rips Orion, Irving St. John R. plan 113 141/mi. Middle quartile 0.8 mi. >250 ft. 0/mi. 2.5 2 Fair 3 Good 2 Fair 2 Fair 3 Good 3 Good Fair/Good Big Black R Junction & Big Seven 4.3 mi./61% NE 749 105/mi. Middle quartile 7.1 mi. >250 ft. 0.1/mi. 2.7 Black River Jxn NW Shore, Islands, Forestry 3 Good 2 Fair 2 Fair 3 Good 3 Good 3 Good Good Camp 107 - Stewart Brook, Irving, Foundation Seminary Brook, Unnamed Prentis & easement on Rapids #2, Long's Rapids Carlisle Seven Islands upriver (N), Long's Rapids land, St. John R. downriver (N), Castonia plan (Prentiss Farm Carlisle no longer in Plan), LUPC Schoolhouse Rapids, Irving Minimum 317 67/mi. Lower quartile 4.7 mi. >250 ft. 0/mi. 2.3 Ouellette Farm upriver, Shoreland zoning 2 Fair 2 Fair 1 Poor 3 Good 3 Good 3 Good Fair Ouellette Farm downriver, Fox Brook Rapids, Fox Brook Ledges, Hafford Brook (N), Poplar Island Rapids, Allagash Campbell Brook, Walker Irving Minimum 142 142/mi. Middle quartile 1.0 mi. >250 ft. 0/mi. 2.5 Brook, Allagash Shoreland zoning 2 Fair 3 Good 2 Fair 2 Fair 3 Good 3 Good Fair/Good
Big Rapids, Dickey Bridge, Irving, Minimum 38 127/mi. Lower quartile 0.3 mi. Modest 3.3/mi. 1.3 Allagash Private Shoreland zoning 1 Poor 2 Fair 1 Poor 1 Poor treeline 1 Poor Poor landowners 2 Fair St Paul's Church downriver, Irving, 1 mi./38% 267 103/mi. Lower quartile 2.6 mi. >50% with 2.3/mi. 2.0 Allagash Delta, Pelletier MBPL, MBPL, minimum 2 Fair 2 Fair 1 Poor 3 Good 250 ft. 2 Fair Fair Brook, Casey Brook - Cross Private Shoreland Zoning buffer Rock, Allagash landowners 2 Fair Wiggins Brook, St. Francis Private Minimum 0 0/mi. Lower quartile 0.3 mi. 1 Poor 6.7/mi. 0.7 landowners Shoreland zoning 0 Very Poor 0 Very Poor 1 Poor 1 Poor 1 Poor Poor Rankin Rapids, St. Francis Private Minimum 0 0/mi. Lower quartile 0.3 mi. 1 Poor 10/mi. 0.7 landowners Shoreland zoning 0 Very Poor 0 Very Poor 1 Poor 1 Poor 1 Poor Poor
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Thibodeau Brook, St. Francis Private Minimum 0 0/mi. Lower quartile 0.6 mi. 1 Poor 0/mi. 1.2 landowners Shoreland zoning 0 Very Poor 0 Very poor 1 Poor 2 Fair 3 Good Poor St. Francis Line, St. Francis Private Minimum 0 0/mi. Lower quartile 0.6 mi. 1 Poor 1.7/mi. 1.0 landowners Shoreland zoning 0 Very Poor 0 Very poor 1 Poor 2 Fair 2 Fair Poor Camel Brook, Fort Kent Private Minimum 13 13/mi. Lower quartile 1.0 mi. 1 Poor 0/mi. 1.5 landowners Shoreland zoning 1 Poor 1 Poor 1 Poor 2 Fair 3 Good Poor Van Buren Private Minimum 0 0/mi. Lower quartile 0.05 mi. Modest 0/mi. 1.0 landowners Shoreland zoning 0 Very Poor Very poor 1 Poor 1 Poor treeline 3 Good Poor 1 Poor Hamlin Private Minimum 0 0/mi. Lower quartile 0.02 mi. Riparian 0/mi. 1.2 landowners Shoreland zoning 0 Very Poor Very poor 1 Poor 1 Poor intact, 3 Good Poor some clearing 2 Fair Hamlin Corners Irving, Minimum 239 956/mi. Lower quartile 0.25 mi. >250 ft., 0/mi. 2.2 Private Shoreland zoning 2 Fair 3 Good 1 Poor 1 Poor reforesting 3 Good Fair landowners 3 Good Aroostook 2 1 Poor Lower quartile 1 Poor 1 Poor Above Grand Falls 70 2 Fair Lower quartile 2 Fair 1 Poor Stirrett Preserve Nature Trust 1 1 Poor Lower quartile 3 Good of New 1Poor 1 Poor Brunswick Medford 64 2 Fair Lower quartile 1 Poor 1 Poor Big Flat 20 1 Poor Lower quartile 1 Poor 1 Poor
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3.3.2.1 Resiliency
Resiliency refers to the ability of populations and species to withstand stochastic events, and is commonly determined as a function of metrics such as population size, growth rate, and habitat quality and quantity. At the subpopulation level, the Furbish’s lousewort needs periodic ice scour, not too frequent or infrequent, to maintain quality habitat. On the St. John River, stochastic events include periodic ice scour and flooding that vary in magnitude from year to year, but typically happen at a magnitude and frequency that the plant has become adapted to.
In this assessment, we determined the resiliency of individual Furbish’s lousewort subpopulations and the metapopulation as a whole using measures of population size, current habitat conditions, and conservation actions. We are fortunate to have 37 years of population monitoring data for the majority of Furbish’s lousewort population in Maine and New Brunswick that allowed us to document the resilience of individual subpopulations. Because the Furbish’s lousewort occurs in an environment dominated by local stochastic and periodic, widespread catastrophic ice scour events, we expect fluctuations in the population. Resilience is the ability of subpopulations to recover from these disturbances and for the metapopulation to remain viable despite periodic declines and increases.
Long-term census data demonstrate that the Furbish’s lousewort is resilient to stochastic events (periodic ice scour, flooding). However, an increase in ice scour events and flooding is anticipated to reduce the level of resiliency. In the 1980s and 1990s, the six upriver subpopulations declined and rebounded in response to multiple, stochastic ice scour events (Figure 7). During this time period, the nine downriver subpopulations in Maine declined and rebounded in response to stochastic ice scour events. However, resiliency diminished greatly in downriver subpopulations in the 1990s and early 2000s. Except for St. Paul’s Church and Hamlin Corners subpopulations, downriver subpopulations are either locally extirpated or at the lowest populations ever recorded. Currently, the Furbish’s lousewort is absent from six of nine downriver subpopulations. Similar declines of plants occurred in New Brunswick, but lousewort is still extant (but at record low numbers) at all five subpopulations.
Resilience at the subpopulation level is currently diminished because Furbish’s lousewort does not tend to colonize new sites and is often very slow to recolonize sites after it is locally extirpated. Therefore, subpopulations that become locally extirpated tend to remain so. In 37 years of monitoring, only one subpopulation, Big Rapids at Dickey Bridge, dropped to zero flowering stems and now supports reproductive plants.3 In contrast, six subpopulations (all downriver) dropped to zero flowering stems and remain locally extirpated.
This pattern of upriver-downriver resiliency is also seen at the metapopulation level. Since 1980, upriver subpopulations (River Segment 1) fluctuated widely but declined at a lower rate (about - 0.6% per year, Figure 7) than downriver subpopulations (about -4.9 percent per year, Figure 7). It is important to note that abundance does not entirely explain resilience. In the 1980s and early 1990s, the Furbish’s lousewort was more abundant in downriver subpopulations. However, these abundant subpopulations were not resilient to stochastic ice-scour events, and their numbers
3 This subpopulation was probably not locally extirpated. Small, vegetative plants probably persisted at the site when no flowering stems were counted (D. Cameron, personal communication, August 6, 2018). 37
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dwindled. Thus, the metapopulation lost much of its resiliency. We believe the loss in resiliency in downriver subpopulations is attributed to habitat loss and degradation because of development and an increase in the severity and frequency of ice scour events. The newly discovery plant sites in Maine and New Brunswick boost current overall metapopulation numbers that otherwise are at all-time lows.
Habitat quality also contributes to the species’ resilience. Habitat in upriver areas is intact in a managed forest landscape, resilient to normal ice scour frequency, and severe erosion events are rare (Table 5). Habitat quality is diminished in downriver areas, less resilient to the current ice scour frequency, and severe erosion events are common (Table 5). Lousewort is not colonizing severely eroded sites and may not for decades, which explains why downriver populations are locally extirpated and not recovering.
We presume the reduction in resiliency observed since the 1990s at both the subpopulation and species level are caused primarily by climate change and development. Warm mid-winter temperatures, winter rain, and increased flow rates began in the 1980s and increased frequency of ice scour events began in the 1990s. Whereas catastrophic ice scour events were responsible for declines in the metapopulation in 1989 and 2003, the most recent decline after 2011 is believed to be caused by more frequent, mid-winter ice scour events and more severe spring ice scour and flooding.
3.3.2.2 Redundancy
Redundancy is defined as a species’ ability to withstand catastrophic events, and is measured by the number of populations, their resiliency, and their distribution and connectivity. Furbish’s lousewort is subject to periodic catastrophic ice scour and flood events that can significantly reduce or eliminate subpopulations. Catastrophic, widespread ice scour events occurred in 1989 and 2003. These catastrophic events caused declines in the metapopulation and some localized extirpation of subpopulations.
The Furbish’s lousewort Recovery Plan (USFWS 1991, entire) established downlisting recovery criteria that incorporated the concept of redundancy. This is a benchmark based on the biological goal of maintaining a viable population and to prevent a concentration of plants within a limited area of the Furbish’s lousewort’s range (USFWS 1991, pp. 33-34). Large, robust subpopulations needed to be distributed throughout four river segments. More widely distributed, robust subpopulations enhance redundancy. The population was more widely distributed and robust in 1989, just prior to the 1991 revision of the recovery plan.
Redundancy has diminished appreciably since 1989, especially at the downriver Segments 2, 3, and 4. Currently, lousewort is absent from six of nine downriver subpopulations. For example, in the 2000-2001 census, most downriver census sites were occupied and supported 73 percent of the total population. In the most recent 2016-2017 census, Furbish’s lousewort was absent from most downriver sites and these subpopulations comprised just 16 percent of the total population.
In New Brunswick, historically all five subpopulations supported over 100 total plants, and the site above Grand Falls and Stirrett Preserve supported more than, or near, 300 total plants. The 2014 census documented Furbish’s lousewort still present at all sites, but no subpopulations 38
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numbered more than 62 total plants. In 2018, there were a total of 167 plants, but no subpopulations exceeded 71 plants, and two of 5 subpopulations have declined to 1, and 2 plants
The Recovery Plan also set habitat protection targets, which are discussed in Section 3.2.5 of this SSA. This is a benchmark based on the biological goal of preventing the concentration of plants and protected habitat within a limited area of the Furbish’s lousewort’s range. Habitat is permanently protected in portions of 2 of 15 subpopulations in Maine and 1 of 5 subpopulation in New Brunswick (table 5). There is no permanent habitat protected in downriver Segments 3 and 4 where redundancy in the U.S. population has been most diminished in recent years.
Redundancy in the downriver subpopulations has diminished, and the condition in the upriver subpopulations has remained constant.
3.3.2.3 Representation
Representation refers to the evolutionary capacity of a species to adapt to environmental change, and is measured by the breadth of genetic or ecological diversity within and among populations, as well as geographic distribution of populations. Overall, ecological diversity is naturally low for the species. Furbish’s lousewort occupies a narrow niche, growing almost exclusively in moist, shaded habitats having appropriate host plants, and is pollinated only by half-black bumble bees. We know of no morphological variation throughout the limited range of this endemic species. Genetic diversity in Furbish’s lousewort is very low (section 2.1). We consider the representative unit to be the entire metapopulation and conclude that the species has low ability to adapt to environmental change.
3.4 Synthesis of Current Condition
The current conditions of Furbish’s lousewort are summarized in table 6. The majority of the subpopulations are currently located upriver in an actively managed forest landscape. These subpopulations, while not large in comparison to what has been previously found downstream, currently show good to fair resiliency, and the redundancy of these subpopulations has not been diminished. In contrast, downriver subpopulations once supported much of the metapopulation. Downriver subpopulations occur in developed areas in Maine and New Brunswick and are currently in fair to poor conditions. Currently, most downriver subpopulations show little to no resiliency; they are locally-extirpated or are at or near all-time low numbers. Redundancy has diminished appreciably in this portion of the species’ range since 1989 with the loss of 6 of 15 subpopulations in Maine. All five subpopulations in New Brunswick are extant, but are at all- time low numbers. Recolonization of locally extirpated subpopulations has not occurred. The Furbish’s lousewort occupies a narrow ecological niche, and there is little genetic, ecological, or morphological variability in the metapopulation. This reduces the species’ ability to adapt to environmental changes. There is a high degree of confidence that climate change is increasing mid-winter temperatures, rainfall, and winter flows (Beltaos 1999, entire; Beltaos 2002, entire; Beltaos and Burrell 2003, entire; Beltaos et al. 2003, entire, Beltaos and Burrell 2015, entire). The Furbish’s lousewort subpopulations need at least a decade between ice scour events to achieve optimal seed production, so shorter disturbance intervals have the potential to harm the species’ survival. It is unlikely that any single catastrophic ice scour or flood event would extirpate the Furbish’s lousewort, because it currently exists as a widely distributed 39
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metapopulation. But multiple stochastic events, or two or more widespread catastrophic events occurring within a 10-year period, could reduce the species to very low numbers.
Table 6. Current conditions of Furbish’s lousewort Individuals Populations Species • About 896 to 1600 adult, • All subpopulations at or near • In 1980s and early 1990s, reproductive plants in lowest recorded numbers species had more robust Maine, about 167 total plants since 1980 populations equally in New Brunswick • Two subpopulations good distributed across range • No colonization of new condition, 2 subpopulations • Since late 1990s, overall sites; recolonization of fair/good, 3 subpopulations decline in the metapopulation locally-extirpated sites is fair, and 8 subpopulations (=species); resiliency and rare poor condition redundancy diminished • Seed predation and • Six upriver subpopulations • Low ability to adapt to herbivory occur maintaining resiliency and environmental change. • The half-black bumble bee redundancy pollinator is still widely • Fourteen downriver distributed populations losing resiliency and redundancy; absent from 6 subpopulations • Largest contiguous habitats upriver; smallest, fragmented, eroded habitats downriver • One upriver subpopulation partially protected • One downriver subpopulation partially protected and one New Brunswick site protected • Habitat degradation (erosion, poor riparian buffer) greatest in downriver habitats
Chapter 4.0 Analysis of Future Condition
4.1 Introduction to Future Risk Scenarios
Based on the analysis of potential stressors currently affecting the species (Section 3.2), we selected climate change and development to be the most important risk factors with the potential to affect Furbish’s lousewort into the future.
We also considered whether possible conservation actions in the future have the potential to minimize the impacts of stressors affecting the Furbish’s lousewort (see Table B). Furbish’s lousewort is a federally endangered species, and recovery actions are prescribed in a recovery plan (USFWS 1992). However, for the purpose of this analysis (determining whether the Furbish’s lousewort warrants listing), we assume the species is not listed now or in the future. We assume that Furbish’s lousewort would remain state-listed, and the Maine Natural Areas Program
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would continue to monitor the population and implement some conservation measures currently prescribed in the recovery plan albeit at a greatly reduced level. However, since MNAP has relied small amounts of federal funding, little or no state funding would be available for surveying and monitoring the Furbish’s lousewort at the past intensity or frequency. We assume that Canada would continue to list Furbish’s lousewort as endangered at both the federal and provincial level and would continue conservation measures described in the Canadian recovery plan (Furbish’s Lousewort Recovery Team 2006, entire), but that its conservation program would address only the subpopulations in New Brunswick. We expect the existing habitat protection described in Chapter 3 will continue. Additionally, it is expected that the St. John River Resource Protection Plan (SJRRPP) will continue to provide voluntary land protection along the St. John River, specifically, to prohibit certain commercial, industrial, and residential development; provide for the continued management of recreational activities; regulate timber harvesting, and restrict new road, bridge, and water impoundment construction, in order to protect the natural values of the St. John River (SJRRPP, p. 4).
We assessed two time frames for characterizing the condition of Furbish’s lousewort in the future. We selected the years 2030 and 2060, as a period for which we can reasonably project effects of the stressors and potential conservation efforts. Climate change information for these timeframes was based on the available information contained in climate predicting models provided through the USGS Climate Change Viewer, Summary of Upper Saint John River watershed, Aroostook County, Maine (8 digit HUC: 010100001) (USGS 2017a, b, entire). The time frames of 2030 and 2060 will capture approximately 1to 2 and 4 to 5 generations of Furbish’s lousewort, respectively. We believe these timeframes will allow observation of changes in the condition of the species without increasing uncertainty about the nature and intensity of stressors beyond a reasonable level. Development information for this timeframe was available in municipal comprehensive plans (Town of Fort Kent 2012, entire) and The University of Maine Sustainability Solutions Initiative - Maine Futures Community Mapper (http://www.mainelandusefutures.org/ last accessed July 19, 2018).
Table 7. Assumptions concerning stressors potentially affecting Furbish’s lousewort in the future. The effects of each stressor and potential conservation actions to mitigate the effects of stressors are provided. Stressor Anticipated change in Effect of stressor on Possible conservation stressor resources or demographic actions assuming Furbish’s factors lousewort is not federally listed Climate change • Increased mid-winter • Reduced reproduction, • Infrequent, opportunistic temperature survival, germination, monitoring of • Increased rainfall in • Increased non-native subpopulations in Maine. mid-winter plant competitors; Periodic monitoring of • Increased frequency • Reduced dispersal; subpopulations in New and severity of ice reduced vigor Brunswick. scour and flooding • Increased summer temperatures , Increased frequency, 41
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severity and duration of summer drought • Influence populations of the half-black bumble bee
Development • Moderate increase in • Increased surface water • Retain current permanent riverfront runoff; loss of riparian land conservation development and forest; riverbank (easements, fee title) to agriculture; removal erosion; loss of habitat; protect habitat in Maine or thinning of forest mortality • LUPC and minimum buffer to create • Decreased shade; shoreland zoning may views of the river changes in continue in Maine • Changes in industrial microclimate; reduced • Site management in New forest land vigor, mortality, Brunswick ownership reduced survival and subpopulations • Changes in forest reproduction • Protection from take in practices; increased New Brunswick demand on riparian • MNAP review forestry forest resources and projects that require state permits
All future predictions are uncertain; therefore, we qualify them using terms such as highly likely, likely, or unlikely. We adopt terminology specified by the IPCC (2014)(appendix 3).
We next looked at how the stressors of climate change and development are likely to change by 2030 and 2060. For each of the two time frames we assessed three future scenarios: a continuation, best case, and worse case.
Predicted future trends in climate change in the St. John River valley For climate scenarios we used data from representative concentration pathways (RCPs) of greenhouse gas (GHG) concentration trajectories adopted by the International Panel on Climate Change (IPCC) in the Fifth Assessment Report in 2014 (see Table 8; IPCC 2014, entire). The three RCPs we selected, RCP2.6, RCP4.5, and RCP8.5,4 are consistent with a wide range of possible changes in future anthropogenic (i.e., human) greenhouse gas (GHG) emissions and commonly used in other SSAs.
The continuation scenario, representing the continuation of current rates of change, is based on emissions in RCP4.5, which predicts that greenhouse gas emissions will peak around 2040, and then gradually decline. The best case scenario is based on RCP2.6, which assumes that global annual GHG emissions have peaked or will peak between 2010 and 2020, and emissions decline substantially thereafter. The worse case scenario is based on RCP8.5, in which emissions
4 The representative concentration pathways (RCPs) are named after a possible range of values of solar energy radiated back to space minus absorbed by the Earth relative to pre-industrial values (+2.6, +4.5, and +8.5 Watts per square meter (W/m2), respectively). 42
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continue to rise throughout the 21st century. Projected greenhouse gas concentrations and projected annual global temperatures for RCP2.6, RCP4.5, and RCP8.5 are depicted in Figure 11. The average global projections (anticipated temperature increased 0F) for these RCPs are provided in Table 8. Projected increases in surface temperatures are greater in northern areas than these global averages.
Table 8. IPCC (AR5 model) climate change projections (average global surface temperature) in degrees Fahrenheit and Celsius5 at the various RCP scenarios. Based on Table SPM.2 in IPCC 2013. 2046-2065 Scenario Mean and likely range RCP2.6 1.8 (0.7 to 2.9)F 1.0 (0.4 to 1.6) RCP4.5 2.5 (1.6 to 3.6)F 1.4 (0.9 to 2.0) RCP8.5 3.6 (2.5 to 4.7)F 2.0 (1.4 to 2.6)
Figure 11. Greenhouse gas emissions and global temperature changes anticipated by three future climate scenarios. We used the RCP2.6 to represent a best-case scenario, RCP4.5 to represent a continuation scenario, and RCP8.5 to represent a worse-case scenario. Graph is from U. S. Global Change Research Program (USGCRP) 2017, figure 3, p. 7 https://science2017.globalchange.gov/chapter/executive-summary/ last accessed August 14, 2018. The three climate scenarios are similar in the near-term (e.g. 2030), but diverge appreciably thereafter (e.g. 2060 and to the end of the century).
To evaluate how the climate along the St. John River may change, we used the National Climate Change Viewer to compare past and projected future climate conditions for the Upper St. John watershed (8-digit HUC 010100001), Aroostook County, Maine. This HUC encompasses nearly the entire range of the Furbish’s lousewort. The baseline for comparison was the observed mean values from 1950 through 2005, and the average of 30 climate models were used to project future conditions. We selected only certain outcomes from the National Climate Change Viewer;
5 Temperature conversions made at https://www.convert-me.com/en/convert/temperature-inc/?u=dcelsiusi&v=1 43
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average maximum mid-winter temperature, maximum summer temperature, summer evaporative deficit, winter precipitation, and winter runoff because they most closely approximated factors affecting the Furbish’s lousewort species needs or because of their importance to ice dynamics on the St. John River (section 3.2.3)(figure 12). The USGS Climate Change Viewer only provides GHG emissions trajectories for RCP4.5 (continuation scenario) and RCP8.5 (worse case scenario), and so we predict that the RCP2.6 (best case scenario) would have substantially lower greenhouse gas emissions and a nearer to flat temperature trajectory. We used both the RCP4.5 and RCP8.5 scenarios to provide a range of climate projections specifically for the Upper St. John River using the USGS National Climate Change Viewer6 (USGS 2017a, b, entire; figure 13).
6 https://www2.usgs.gov/climate_landuse/clu_rd/nccv/viewer.asp last accessed July 19, 2018. 44
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Figure 13. Projections of climate factors relevant to Furbish’s lousewort species needs. The black lines in the graphs represent current data to 2005, the blue line represents the RPC4.5 projection, and the red line represents the RPC8.5 projection. The projections represent the average of 30 different climate models, and the shaded area is one standard deviation around the mean. The months considered are above each graph. For example DJF=December, January, and February.
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The following projections were derived from the results of the National Climate Change Viewer for the Upper St. John River watershed (USGS 2017a, b, entire): • Average maximum mid-winter temperatures. The average maximum mid-winter temperatures, an important driver of ice scour frequency and severity in the St. John River watershed, will increase about 2.50 F (both RCP4.5 and RCP8.5) by 2030 and about 3.50 F (RCP4.5) and 4.50F (RCP8.5) by 2060 above 2005 levels. Thus, we expect the number of days in January and February above freezing will continue to increase (Figures 8 and 9, section 3.2.3). By 2030, we estimate an average of 24 percent of mid-winter days (both RPC4.5 and RPC8.5) may be above freezing, and by 2060 an average of 25 percent (RPC4.5) to 27 percent (RPC8.5) of mid-winter days may be above freezing. More frequent breakup of ice in mid-winter and associated jamming and flooding can be predicted with some confidence (Beltaos and Prowse 2009, p. 137). This phenomenon was first observed on the St. John River in the 1990s coincident with small increases in mid-winter temperatures (Beltaos and Burrell 2002, entire; Kim and Jain 2015, figure 2, figures 8 and 9 section 3.2.3). We presume that more frequent mid-winter breakup, ice jamming, and flooding will continue through 2030 and 2060 under low (RCP2.6), moderate (RCP4.5), and high (RCP8.5) scenarios because of the lag effect of reducing atmospheric GHG even under the most optimistic scenario (RCP2.6) (figure 11). • Average maximum summer temperatures and summer evaporation deficit. The average maximum summer temperatures in the St. John watershed will increase about 2.5 0F (both RCP4.5 and RCP8.5) by 2030 and about 4.5 0F (RCP4.5) and 6.0 0F by 2060 (RCP8.5) above 2005 levels. The climate envelope (maximum summer temperatures and evaporation) that Furbish’s lousewort can tolerate is unknown. The summer evaporation deficit is expected to increase gradually in response to climate change, with 2030 and 2060 deficits slightly above 2005 levels. The summer temperature, precipitation, and evaporation deficits equate with similar predictions for hotter, slightly drier summers in northern Maine (Jacobson et al. 2009, p. 15). Climate change is expected to increase droughts in the Northeast (Manomet Center for Conservation Sciences and National Wildlife Federation 2013, pp. 50, 63). Under a high emissions scenario, the frequency of short-term droughts (1-3 months in duration) will nearly double and occur about every 3 of 4 years. The frequencies of medium term droughts (3-6 months duration) will more than triple and occur about once every 15 years. Less severe changes are projected under a low climate scenario.7 Increases in drought are most likely to occur late in the plant growing season (Jacobson et al. 2009, pp. 4, 28) when the Furbish’s lousewort is flowering and setting seed. Menges et al. 1984 (p. 12) documented that many reproductive plants senesced early and did not produce seed on drier sites. Under moderate (RPC4.5) and high (RPC8.5) scenarios, we are moderately confident that stress from these projected changes in summer maximum temperatures, soil moisture, precipitation, evaporative deficit, and drought will reduce the vigor of the Furbish’s lousewort plants. • Average winter precipitation and winter runoff. These factors will be influenced by warmer average mid-winter temperatures and greater temperature extremes (above) and will affect the flow and ice scour regime of the St. John River. Average mid-winter precipitation will increase a few tenths of an inch by 2030 and 2060 (both RPC4.5 and
7 Manomet Center for Conservation Sciences and National Wildlife Federation (2013) projected to the period 2070- 2099 using a high emissions model (A1fi) similar to RPC8.5 and lower emissions model (B1) similar to RPC4.5. 46
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RPC8.5). Mid-winter flow rates are projected to remain relatively stable through 2030 and 2060 (both RPC4.5 and RPC8.5). These projections from the National Climate Change Viewer are in contrast to observed data that flow rates of the St. John River are increasing and seasonal maximum flows have increased significantly in the decade from 2000-2010 (figure 10; Kim and Jain 2015, figure 1, p. 3). Seasonal flows are usually lowest in the winter as water is tied up in ice and precipitation as snow (Beltaos and Prowse 2009, pp. 126-127), but winter flows have increased substantially on the St. John River as a result of increased, mid-winter rainfall caused by a marked increase in the incidence of mild temperatures (Huntington et al. 2004, pp.2632-2634, Beltaos 2002, entire). Seasonal flows are expected to rise in northern rivers because of climate change and result in more severe flooding and ice jamming (Beltaos and Prowse 2009, pp. 130, 134-136). We expect increased winter precipitation, ice jams, and winter-spring runoff to increase the frequency and severity of ice scour. In the past, a few Furbish’s lousewort plants located higher on riverbank escape ice scour and helped to repopulate habitats in subsequent years. Increased severity of ice jamming and associated flooding could increase the height, extent, and severity of the ice scour zone on the river banks, thus removing more of the Furbish lousewort plants.
Predicted trends in development in the St. John River valley To our knowledge, there are no build-out scenarios for communities in the St. John River valley. Land use planning models are available for some areas of Maine, but not for the St. John River valley. Instead, we examined buildout scenarios from The Maine Futures Community Mapper for other rural Maine communities along the Penobscot River in north-central Maine. We assumed scenarios with modest population growth. We examined build-out scenarios to 2038 for Lincoln (a service-center community similar in size to Fort Kent) and Winn (a small town adjacent to Lincoln similar to St. Francis or Allagash). We noticed several trends, which we believe represent future development and agriculture trends for communities in the St. John River: • Most of the future development will occur in the town center of larger towns and in rural areas along the major highways. • Rural development (single-family housing, subdivisions), in part, will expand into some areas currently in agricultural land use, especially those farms located closest to the larger towns. These are the easiest to develop and often have an added value of river views and access. • The footprint of agricultural land use is unlikely to expand.
We anticipate that forestry will remain the primary land use in the upriver segment of the Furbish’s lousewort range through 2060. Although land ownership and forest management practices may change in the unorganized townships of Maine, we expect forestry in the riparian zone to remain unchanged through 2060 (i.e., no more than 40percent of the riparian forest may be harvested every decade).
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4.2 Scenarios
For each of the two time frames (2030 and 2060), we developed three future scenarios: continuation, best case, and worse case (table 9). We provide a range of reasonable, plausible effects for development and climate change based on the information obtained from the USGS Climate Change Viewer (USGS 2017a, b, entire), The Maine Futures Community Mapper, and other information compiled in the previous section. Conservation actions will be minimal in the United States, but some conservation will occur in Canada (table 9).
• The continuation scenario assumes moderate increases in GHG emissions (RCP4.5). The current frequency and severity in ice scour would continue or increase slightly. Long term declining trends in the metapopulation likely would continue. It is anticipated that agricultural land will be converted to development at a modest rate in the downriver subpopulation. Habitat quality remains diminished at downriver subpopulations. Conservation measures provided by the SJRRPP will remain in place; existing permanent habitat protection will continue, and LUPC and minimum shoreland zoning will continue. The monitoring of the Maine subpopulations will be reduced to once every 5 to 10 years, but the New Brunswick subpopulations will continue to be monitored more frequently. • The best case scenario assumes low GHG emissions and reduced development occurs into the future. Current frequency and severity in ice scour continues. Conservation measures provided by the SJRRPP will remain in place, and existing habitat protection will continue. The Maine subpopulations will be monitored once every 5 to 10 years and the New Brunswick subpopulations more frequently. • The worse case scenario assumes high GHG emissions and moderate increases into the future. Frequency and severity of ice scour increases. Summer temperatures increase, precipitation remains the same or falls slightly, and soil moisture declines. Frequency of summer drought increases. Half-black bumble bee populations decline and pollination is reduced. Lousewort is outside of its summer maximum climate envelope. Reduced conservation measures in Maine; no change in New Brunswick.
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Table 9. Summary of factors affecting Furbish’s lousewort under future scenarios at the 2030 and 2060 time frames, including effects of climate change and development as stressors. Potential conservation actions that could hypothetically be implemented are also noted. 2030 Scenario Climate change Development (downriver Probable conservation actions, Furbish’s areas only) lousewort not listed in United States Emissions continue to rise based on RCP4.5 peaking about 2040 and Current low to moderate levels of Monitoring of subpopulations in Maine once every 5 to 10 then declining gradually. Maximum average mid-winter development and clearing of forested years. More frequent monitoring in New Brunswick. temperatures increase 2.50F. Maximum average summer buffer continue through 2060. Some temperatures increase 2.50F. Average winter precipitation and winter agricultural land along the river will Retain current permanent land conservation (easements, fee runoff increases slightly and continues to rise. become developed. title) to protect habitat in Maine and New Brunswick Continuation (Very likely) Majority of winters with multiple ice scour events. More frequent LUPC and minimum shoreland zoning continue in Maine severe ice scour events and flooding. Ice scour of lousewort habitat more frequent than optimum (e.g., once per 6 years average) Site management in New Brunswick subpopulations
Climate envelope or niche remains suitable for Furbish’s lousewort Protection from take in New Brunswick
Exotic invasive plant species remain the same. SJRRPP Implemented
Half-black bumble bee remains widespread in the St. John River valley and remains an effective pollinator Emissions continue to rise based on RCP2.6 peaking between 2010 No further development or agriculture Monitoring of subpopulations in Maine once every 5 to 10 and 2020, and then substantially declining. Maximum average mid- within the riparian area years. More frequent monitoring in New Brunswick. winter temperatures increase slightly. Maximum average summer temperatures increase slightly. Average winter precipitation as rain Forested riparian quality increases in Retain current permanent land conservation (easements, fee increases slightly. Winter runoff increases slightly. downriver areas title) to protect habitat in Maine and New Brunswick Best case (Highly Some winters with multiple ice scour events. Ice scour slightly more LUPC and minimum shoreland zoning continue in Maine frequent than optimum (once per 8 years average). Unlikely) Site management in New Brunswick subpopulations Climate envelope or niche remains suitable for Furbish’s lousewort Protection from take in New Brunswick\ Exotic invasive plant species remain, but are at minimal levels; not competing with lousewort SJRRPP Implemented
Half-black bumble bee remains widespread in the St. John River valley and remains an effective pollinator Worse case Emissions continue to rise based on RCP8.5 rising continually Current modest levels of development Monitoring of subpopulations in Maine once every 5 to 10 (Very likely) throughout the century. Maximum average mid-winter temperatures, and clearing of forested buffer continue years. More frequent monitoring in New Brunswick. maximum average summer temperatures, winter precipitation and Some agricultural land along the river runoff about the same as the continuation scenario (effects have not will become developed. Retain current permanent land conservation (easements, fee diverged yet). title) to protect habitat in Maine and New Brunswick
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LUPC and minimum shoreland zoning continue in Maine Climate envelope or niche remains suitable for Furbish’s lousewort. Site management in New Brunswick subpopulations Exotic invasive plant species remain the same. Protection from take in New Brunswick Half-black bumble bee remains widespread in the St. John River valley and remains an effective pollinator SJRRPP Implemented with fewer landowners
2060 Scenario Climate change Development (downriver Possible conservation actions areas only) Emissions continue to rise based on RCP4.5 peaking about 2040 and Current low to moderate levels of Monitoring of subpopulations in Maine once every 5 to 10 then declining gradually. Maximum average mid-winter development and clearing of forested years. More frequent monitoring in New Brunswick. temperatures increase 3.50F. Maximum average summer buffer continue. temperatures increase 3.50F. Average winter precipitation increases, LUPC and minimum shoreland zoning will continue in especially in the form of rain. Winter runoff increases and continues More agricultural fields become Maine to rise. subdivisions. Site management in New Brunswick subpopulations Multiple ice scour events (upriver and downriver) and flooding occur Forested riparian buffer diminished or Continuation almost every winter. Ice scour more frequent than optimum (once per poor quality and most downriver sites. Protection from take in New Brunswick (Very likely) 3 to 5 years average) SJRRPP Implemented Furbish’s lousewort stressed in changing climate envelope; plants stressed at most locations, seed set and germination no longer occur annually.
Exotic invasive plant species increase, compete with lousewort.
Half-black bumble bee declines in the St. John River valley Emissions continue to rise based on RCP2.6 peaking between 2010 Monitoring of subpopulations in Maine once every 5 to 10 and 2020, and then substantially declining. Maximum average mid- No further development or agriculture years. More frequent monitoring in New Brunswick. winter temperatures decline slightly from current levels. Maximum along river edge average summer temperatures decline slightly from current levels. LUPC and minimum shoreland zoning will continue in Average winter precipitation returns to current levels. Winter runoff Riparian buffer remains intact and is Maine Best case returns to current levels. improved in some areas (Highly Site management in New Brunswick subpopulations Unlikely) Occasional winters with multiple ice scour events. Ice scour returns More agricultural fields become to near-optimum (once per 10 years average). subdivisions. Protection from take in New Brunswick
Climate envelope or niche remains suitable for Furbish’s lousewort. Forested riparian buffer diminished or SJRRPP Implemented poor quality and most downriver sites. Exotic invasive plant species remain the same, few problem areas,
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control effective.
Half-black bumble bee remains widespread in the St. John River valley and remains an effective pollinator Emissions continue to rise based on RCP8.5 rising continually Possible increase levels of development Monitoring of subpopulations in Maine once every 5 to 10 throughout the century. Maximum average mid-winter temperatures and associated clearing of forested years. More frequent monitoring in New Brunswick. increase 4.50F. Maximum average summer temperatures increase buffer. Otherwise, current modest levels 6.0 0F. Average winter precipitation frequently in the form of rain. of development and clearing of forested LUPC and minimum shoreland zoning will continue in Winter runoff substantial, lower spring runoff. buffer continue. Maine
All winters with widespread, multiple ice scour events OR ice scour More agricultural fields become Site management in New Brunswick subpopulations diminishes completely. subdivisions. Worse case Protection from take in New Brunswick Summer climate envelope begins to exceed the tolerance limits of (Likely) Furbish’s lousewort; seed set and germination declined. Forested riparian minimal nearly all SJRRPP Implemented with fewer landowners downriver sites. Exotic invasive plant species increase, compete with lousewort.
Half-black bumble bee declines in the St. John River valley; pollination not predictable.
Riverbank heavily scoured OR trees and shrubs begin to grow to shoreline like other northern Maine rivers
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4.3 Predicting the Future Condition
To predict the future condition for Furbish’s lousewort across the two time frames (2030, 2060) and three risk scenarios (continuation, best case, worse case), we assessed what changes to habitat and demographic factors would occur as a result of predicted changes in development and the climate (table 9). Due to the similarity in population and habitat attributes (Chapter 3), we consolidated upriver (6 subpopulations) and downriver (14 subpopulations including New Brunswick).
The following discussion describes the viability of Furbish’s lousewort in the continuation, best case, and worse case scenarios in 2030 and 2060.
4.3.1 Continuation Scenario
We consider this scenario to be very likely because historic and observed GHG emissions and global temperature increases are thus far tracking the higher emissions scenarios,8 and there is a high degree of confidence that global temperatures will continue to rise under RPC4.5 and RPC8.5 scenarios through the end of the century9 (U. S. Global Change Research Program 2017, Figure 3, p. 7-8; Vose et al. 2017, p. 185, 195-199, 201-202). In the continuation scenario for 2030 (table 9, 2030), the trajectory of changing climate and other stressors remains at the current pace. Although the RPC4.5 scenario predicts GHG emissions will be curbed, atmospheric GHG will peak about 2070 and then remain stable (figure 12). Because average winter maximum temperatures are projected to increase about 2.5 0F by 2030, we anticipate that the number of mid-winter days above freezing will continue to increase and result in more winters with multiple ice scour events. By 2030 we predict that ice scour events on average will be more frequent than is optimum for lousewort, and ice scour events will affect more locations on the river where lousewort populations occur. Effects would be most pronounced in downriver populations and in Canada where subpopulations are found in smaller habitat patches, and nearly all of which are already severely diminished or locally extirpated. This phenomenon is already occurring and is likely responsible, in part, for the declines in lousewort populations observed since 2011 (figure 8). Relative to downriver populations, upriver populations will be more resilient to increased ice scour frequency because habitat is more extensive. However, increased ice scour frequency in any section of the river may interfere with the 6 – 10 year time needed for sub-populations or patches to recover (Menges 1990, p. 59) Also, if one or more severe, widespread ice scour events occurs, habitat in the upriver subpopulations would be diminished and therefore could lose resiliency. Under this scenario, we predict low to moderate levels of development would be expected, some near lousewort habitats. This development could further degrade the riparian forest buffer and exacerbate erosion in downriver subpopulations as they have in recent years.
The continuation scenario would be expected to result in further declines in Furbish’s lousewort populations by 2030. Declines would be caused by mortality and degradation of habitat from
8 RCP 4.5 is a stabilization scenario and assumes that climate policies, including the introduction of a set of global greenhouse gas emissions prices, are invoked to achieve the goal of limiting emissions, concentrations and radiative forcing. 9 Much larger rises in global temperature are projected with high confidence by late century (2071–2100): 2.8°– 7.3°F (1.6°–4.1°C) in a lower scenario (RCP4.5) and 5.8°–11.9°F (3.2°–6.6°C) in the higher scenario (RCP8.5) (high confidence)( Vose et al. 2017, p. 185). 52
Species Status Assessment Report for the Furbish’s lousewort ● Version 1.1 increasingly frequent ice scour events, and from low to moderate development. It is anticipated that colonization will not keep up with local extirpations, and the number of subpopulations will continue to decline. Under this scenario, summer temperatures and drought will probably not increase enough to consistently stress plants, but this could begin to occur in the warmest summers.
If current trends continue for climate change and development, we would expect reduced resiliency and redundancy by 2030. Redundancy would continue to decline as more subpopulations are lost from the metapopulation. This would further exacerbate the low representation of the species.
Without federal protection existing permanent habitat protection would likely remain in place in Maine, and the population would likely be monitored once every 5 to 10 years rather than annually. Less frequent monitoring would impact knowledge of population fluctuations, and information available on the effects of climate change, ice scour, and habitat loss on the metapopulation. Site management would likely continue in New Brunswick.
If current trends continue to 2060 (table 10, 2060), we expect greater winter and summer warming than in 2030. Multiple ice scour events in mid-winter would become more common by 2060. The upriver subpopulations would have difficulty rebounding from frequent and occasionally severe ice scour events. More extensive bank slumping and erosion would occur downriver and degrade what limited habitat remains. Summer maximum temperatures will further stress plants on sites at the drier end of the species tolerance, and by 2060 may exceed the climate envelope of the species. By 2060, we anticipate a noticeable decline in the vigor of the remaining plants. Where Furbish’s lousewort still occurs, we expect a decline in seed production (from fewer, less mature plants); a reduction in germination due to higher spring temperatures; and a decline in recruitment of new plants.
In summary, under the continuation scenario we anticipate that resiliency and redundancy for Furbish’s lousewort would diminish by 2030 with the loss of more downriver and one or two upriver subpopulations, but by 2060 lousewort would likely be extirpated from all but a few upriver sites in Maine. Continued local extirpations of subpopulations would occur, indicating a loss in redundancy by 2030 and 2060. Loss of subpopulations further reduces resiliency. Representation, already at low levels, would be further decreased as subpopulations become, fewer, more fragmented.
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Table 10. Prediction of future resilience for each of the demographic and habitat factors for Furbish’s lousewort in 2030 and 2060, the overall future condition, and the overall future condition with the implementation of conservation actions. Overall condition is determined through averaging all demographic and habitat factors equally. Green-high, yellow=moderate, red=low, gray=very poor conditions. 2030 Scenario Demographic Factors Habitat factors Overall Abundance Density Current status w/in Length of Riparian buffer Erosion events Future condition
the site habitat Current 2.2 2.5 1.7 2.3 2.7 2.7 2.35 Fair Fair/Good Fair Fair Good Good Fair Continuation 2 2 1 2 3 2 2.0 10 Fair Fair Poor Fair Good Fair Fair Upriver Best case 2 2 1 2 3 3 2.2 Fair Fair Poor Fair Good Good Fair Worst case 2 2 1 2 3 2 2.0 Fair Fair Poor Fair Good Fair Fair Current 0.8 1.0 1.0 1.6 1.4 2.3 1.35 Poor Poor Poor Fair Poor Fair Poor Continuation 0 0 1 1 1 1 0.7 Very poor Very poor Poor Poor Poor Poor Poor Most populations Most populations Most populations locally extirpated locally extirpated locally extirpated Downriver11 Best case 1 1 1 2 2 1 1.3 Poor Poor Poor Fair Fair Poor Poor A few individuals at A few individuals at A few individuals some locations some locations at some locations Worst case 0 0 1 1 1 1 0.7 Very poor Very poor Poor Poor Poor Poor Poor Most populations Most populations Most populations locally extirpated locally extirpated locally extirpated
10 Segment 1 in the recovery plan; subpopulations upriver of Dickey Bridge, Allagash. 11 Segments 2, 3, 4 in the recovery plan; subpopulations in Maine downriver of Dickey Bridge, Allagash including 5 populations in New Brunswick.
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2060 Scenario Demographic Factors Habitat factors Overall Abundance Density Current status w/in Length of Riparian buffer Erosion events Future condition the site habitat Current 2.2 2.5 1.7 2.3 2.7 2.7 2.35 Fair Fair/Good Fair Fair Good Good Fair Continuation 1 1 1 1 3 2 1.5 Poor Poor Poor Poor Good Fair Poor Species not viable, Species not viable, Species not viable, Habitat areas Forested riparian Moderate erosion near extirpation near extirpation near extirpation dry, diminished still intact from ice scour, flooding Best case 1.5 1.5 1 2 3 3 2.0 Upriver12 Poor/Fair Poor/Fair Poor Fair Good Good Fair One moderate One moderate One moderate Forested riparian Minimal erosion subpopulation, low subpopulation, low subpopulation, low still intact populations at most populations at most populations at locations locations most locations Worst case 0 0 1 1 3 2 1.2 Very Poor Very Poor Poor Poor Good Fair Poor Species not viable, Species not viable, Species not viable, Habitat areas Forested riparian Moderate erosion near extirpation near extirpation near extirpation dry, diminished still intact from ice scour, flooding Current 0.8 1.0 1.0 1.6 1.4 2.3 1.35 Poor Poor Poor Fair Poor Fair Poor Continuation 0 0 1 1 1 1 0.7 Very Poor Very Poor Poor Poor Poor Poor Poor Species not viable, Species not viable, Species not viable, Sites heavily near extirpation near extirpation near extirpation eroded Downriver13 Best case 1 1 1 1 1 1 1.0 Poor Poor Poor Poor Poor Poor Poor Sites heavily eroded Worst case 0 0 1 1 1 1 0.7 Very Poor Very Poor Poor Poor Poor Poor Poor Species not viable, Species not viable, Species not viable, Sites heavily near extirpation near extirpation near extirpation eroded
12 Segment 1 in the recovery plan; subpopulations upriver of Dickey Bridge, Allagash. 13 Segments 2, 3, 4 in the recovery plan; subpopulations in Maine downriver of Dickey Bridge, Allagash including 5 populations in New Brunswick.
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4.3.2 Best Case Scenario
We consider this scenario to be highly unlikely because GHG emission scenarios are highly unlikely to decline in the near term. The best case scenario assumes that global annual GHG emissions have peaked or will peak about 2040 and return to current levels by about 2060 (table 8, Figure 12). Even if GHG emissions decline in the near-term, winter and summer temperatures will still increase slightly above current levels then stabilize through 2060. The current ice scour regime will remain, but there will be some periods when ice scour frequency is not optimal for lousewort. Maximum summer temperatures, rainfall, and soil moisture will remain within the current levels of variation through 2030 and 2060. Summer temperatures are unlikely to affect plant vigor, seeding, and germination rates. The Furbish’s lousewort will likely continue to experience a growing season similar to today. In the best case scenario for both 2030 and 2060, development will remain low to moderate and forestry land use will continue at the current rate for the upriver habitat segment. The Furbish’s lousewort will remain distributed throughout its current range, including New Brunswick.
Without Federal listing in Maine, it is anticipated that the metapopulation will be censused once every 5 to 10 years, and there would be little landowner outreach. Habitat degradation associated with development would continue in the downriver subpopulation in Maine. Federal and provincial efforts in New Brunswick would continue and some subpopulations there may increase to former levels with intensive management. There could be additional permanent habitat protected.
In summary, under the best case scenario for both 2030 and 2060, climate change and development will have minimal effect on Furbish’s lousewort demographics and abundance. We anticipate the metapopulation of the Furbish’s lousewort would remain at viable numbers, and would retain adequate levels of resiliency. We presume the number of occupied downriver subpopulations would continue to decline because the habitat at some sites is eroded and would take decades to recover. Upriver subpopulations would continue to be more resilient because habitat is more extensive.
4.3.3 Worse Case Scenario
We believe this scenario is very likely, because historical and observed GHG emissions and global temperature increases are tracking the RCP8.5 scenario (figure 12),14 and there is a high degree of confidence that global temperatures will continue to rise under the RPC4.5 and RPC8.5 scenarios through the end of the century15 (U. S. Global Change Research Program 2017, Figure 3, p. 7-8; Vose et al. 2017, p. 185, 195-199, 201-202). In the worse case scenario, we expect
14 The RCP8.5 storyline describes a high emission, business as usual world with continuously increasing global population of 12 billion by 2100 leading to high energy demands, slow economic growth, high demand for food, and slow progress toward energy efficiency. Conventional oil and gas become relatively scarce and there is increased reliance unconventional fossil fuels; tar sands and oil shale and coal-intensive energy. Renewable energy (solar, wind, hydro) supply about 15 percent of energy and there is minimal energy conservation (compared to RCP2.6 and 4.5)(Riahi et al. 2011, pp. 42-44). 15 Much larger rises are projected by late century (2071–2100): 2.8°–7.3°F (1.6°–4.1°C) in a lower scenario (RCP4.5) and 5.8°–11.9°F (3.2°–6.6°C) in the higher scenario (RCP8.5) (high confidence)(Wuebbles et al. 2017b p.. 56
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average maximum winter air temperatures to increase about 2.50 F by 2030 and about 4.50F (RCP8.5) by 2060 (figure 13). Similar to the continuation scenario, rising temperatures will likely increase ice scour frequency and severity along with jamming and associated flooding. We expect erosion and bank slumping to increase and to render some additional habitats areas permanently unusable by lousewort by 2030. We expect maximum summer air temperatures to increase about 2.50 F by 2030 and about 60 F by 2060, and summer precipitation will remain about the same. Overall, soil moisture will decline and drought conditions will become more frequent and increase the summer evaporation deficit. By 2060, it is possible that Furbish’s lousewort, a subboreal species that prefers a cool, moist climate, may be outside of its thermal envelope. We anticipate Furbish’s lousewort will experience thermal stress that will diminish plant vigor and reproduction. Populations of the half-black bumble bee may experience declines.
By 2030, we expect the resiliency of individual subpopulations to decline as a result of smaller populations and ice-damaged habitats. Overall, the metapopulation (=species) will be less resilient. Genetic diversity is already low thus representation will remain the same by 2030.
By 2060, Furbish’s lousewort may still occur at a few upriver subpopulations but the subpopulations will not be resilient and the metapopulation may not be viable. The subpopulations of Furbish’s lousewort will likely be locally extirpated from most, if not all, downriver and New Brunswick subpopulations. Thus, the species’ resiliency and redundancy will be further diminished. Representation, already low, will be further diminished.
Chapter 5. Synthesis and Viability
Potential stochastic and catastrophic events that may affect resiliency and redundancy of individual subpopulations and the metapopulation of Furbish’s lousewort in the future are development and climate change. In the previous section, these stressors are discussed in detail for three future risk scenarios; continuation, best case, and worse case. Anticipated effects on the 3 Rs are summarized in table 11.
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Table 11. Comparing resiliency, redundancy and representation under the continuation, best case and worse case scenarios described above. We assessed the species as if it were not listed in the United States, but were to remain state-listed in Maine and federally and provincially listed in Canada. Sideways arrows mean about the same as current conditions, and downward arrows means declining 3Rs.
Scenarios Viability elements Continuation Best case Worse case 2030 2060 2030 2060 2030 2060 Upriver subpopulations ↓ ↓ ↔ ↔ ↓ ↓ resilience Downriver subpopulations ↓ ↓ ↔ ↓ ↓ ↓ resilience (already very low) Overall metapopulation ↔ ↓ ↔ ↔ ↓ ↓ resilience Species representation ↔ ↓ ↔ ↔ ↓ ↓ Species redundancy ↓ ↓ ↔ ↓ ↓ ↓
In Chapter 3, we assessed the current condition of Furbish’s lousewort by reviewing the current status of the 3Rs in terms of individual and population-level resilience; redundancy, and representation as indicated by diversity in ecological, morphological, and phenotypical characteristics and the condition of this species having a narrow, specialized ecological niche. Our results indicate that Furbish’s lousewort currently has marked differences in resiliency and redundancy in upriver and downriver populations. Upriver subpopulations, (currently about 1,721 flowering stems in Maine or 688 to 1229 reproductive individuals in 6 subpopulations; 77 percent of the total current population) are currently resilient because the habitat supporting the species is more extensive. Downriver subpopulations (currently about 520 flowering stems in Maine 208 to 371 reproductive individuals and 167 total plants in New Brunswick in 14 subpopulations; 33 percent of the total current population) currently have diminished resiliency because the subpopulations are small and habitat is less extensive and is fragmented. Six of the downriver subpopulations have been considered extirpated since the late 1990s, and all subpopulations in Canada are occupied and at historically low numbers.
The metapopulation (=species) currently has less resiliency and redundancy, evidenced by numbers of lousewort at or near all-time lows in Maine and New Brunswick. Historically, Furbish’s lousewort was more abundant, and the metapopulation was more equally distributed across subpopulations. Since the last population peak in 2011, the metapopulation has been declining at about 20 percent per two year census periods and has not rebounded as it did after previous major ice events in 1989 and 2003 (D. Cameron, Maine Natural Areas Program, personal communication August 9, 2018; Maine Natural Areas Program 2017, p. 5; Appendix 2). Genetic studies indicate Furbish’s lousewort currently has low genetic diversity and representation, has a narrow ecological niche, and is not well adapted to a changing environment.
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In Chapter 4, we evaluated the potential future condition of Furbish’s lousewort by predicting the response of individual subpopulations and the metapopulation (=species’) to a range of plausible future scenarios involving changes in development and climate, which were determined the most likely stressors to affect the species into the future. Based on this future analysis we conclude:
By 2030: • We believe it is very likely that, in all three scenarios, the metapopulation of Furbish’s lousewort will continue to decline due to local extirpations of downriver subpopulations. • We believe it is likely that, in all three scenarios, the overall viability of the metapopulation (=species) will decline.
By 2060: • For the best case scenario, we believe it is likely that the overall viability of the metapopulation (=species) will be greatly reduced from current conditions, and a few subpopulations will persist upriver in Maine. • We believe it is very likely in both the continuation and worse case scenarios that the metapopulation (=species) will no longer be viable; it will be extirpated throughout most of its range; and the few plants that remain would be concentrated at upriver sites.
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Literature cited
43 FR 17910-17916. Endangered and Threatened Wildlife and Plants. Final Determination on the Elven Plant Taxa are Endangered and Two Plant Taxa are Threatened Species. April 26, 1978.
70 FR 46467-46470. Endangered and Threatened Wildlife and Plants. 90-Day Finding on a Petition To Delist Pedicularis furbishiae (Furbish lousewort) and Initiation of a 5-Year Status Review. August 10, 2005.
75 FR 47025-47026. Endangered and Threatened Wildlife and Plants. Initiation of 5-Year Reviews of Five Listed Species: Delmarva Peninsula Fox Squirrel, Northeastern Bulrush, Furbish Lousewort, Chittenango Ovate Amber Snail, and Virginia Round-Leaf Birch. August 4, 2010.
Antonovics, J. 1984. Genetic variation within populations. Pages 229-241 in R. Dirzo and J. Sarukhan, editors. Perspectives on plant population biology. Sinauer Associates, Sunderland, Massachusetts.
Beginning With Habitat 2017. St. John River focus area. https://www.maine.gov/dacf/mnap/focusarea/st_john_focus_area.pdf last accessed May 9, 2018.
Beltaos, S. 1997. Onset of river ice breakup. Cold Regions Science and Technology. 25(3):183- 196.
Beltaos, S. 1999. Climatic effects on the changing ice-breakup regime of the Saint John River. Pages 8-11 in River Ice Management with a Changing Climate: Dealing with Extreme Events, Proceeding of the 10th Workshop on River Ice.
Beltaos, S. and T. D. Prowse. 2001. Climate impacts on extreme ice jam events in Canadian rivers. Hydrological Sciences Journal 46(1):157-182.
Beltaos S. 2002. Effects of climate on mid winter ice jams. Hydrological Processes 16(4): 789– 804.
Beltaos, S. and B. C. Burrell. 2002. Extreme ice jam floods along the Saint John River, New Brunswick. Pages 9-14 in The Extremes of the Extremes: Extraorfinary Floods. (Proceedings of a Symposium held at Reykavik, Iceland, July 2000. IAHS Publication No. 271. IAHS Press: Wallingford.
Beltaos, S. and B. C. Burrell. 2003. Climatic change and river ice breakup. Canadian Journal of Civil Engineering 30(1):145-155.
Beltaos, S., S. Ismail, and B. C. Burrell. 2003. Midwinter breakup and jamming on the upper Saint John River: a case study. Journal of Civil Engineering, 30 (13), 77–88.
Beltaos, S. and T. D. Prowse. 2009. River-ice hydrology in a shrinking cryosphere. Hydrological Processes 23:122-144. 60
Species Status Assessment Report for the Furbish’s lousewort ● Version 1.1
Beltaos, S. and Burrell. 2015. Hydrotechnical advances in Canadian river ice science and engineering during the past 35 years. Canadian Journal of Civil Engineering 42(9):583-591.
Beltaos S. and Burrell, B.C. 2015. Hydroclimatic aspects of ice jam flooding near Perth-Andover, New Brunswick. Canadian Journal of Civil Engineering 25(42):686-695.
Burakowski, E. A., C. P. Wake, B. Braswell, and D. P. Brown. 2008. Trends in wintertime climate in the northeastern United States: 1965–2005. Journal of Geophysical Research: Atmospheres, 113(D20).
Burgman, M. A., H. P. Possingham, A. J. J. Lynch, D. A. Keith, M. A. McCarthy, S. D. Hopper, W. L. Drury, J. A. Passioura, and R. J. Devries. 2001. A method for setting the size of plant conservation target areas. Conservation Biology 15(3):603-616.
Cameron, D. 2018. Maine Natural Areas Program, Augusta, Maine. Personal communication re: lack of evidence that Furbish’s lousewort colonizes new sites to Mark McCollough, USFWS, Orland, Maine. June 4, 2018.
Cameron, D. 2018. Maine Natural Areas Program, Augusta, Maine. Personal communication re: lack of evidence that Furbish’s lousewort colonizes new sites to Mark McCollough, USFWS, Orland, Maine. June 4, 2018.
Cameron, D. 2018. Maine Natural Areas Program, Augusta, Maine. Personal communication re: Some ice scoured sites formerly supporting Furbish’s lousewort seem incapable of supporting the species for several decades to Mark McCollough, USFWS, Orland, Maine. August 6, 2018.
Cameron, D. 2018. Maine Natural Areas Program, Augusta, Maine. Personal communication re: The reasons for the most recent population declines may be increased erosion and habitat loss and smaller, but more frequent ice scour events that diminish the habitat at many of the Maine populations to Mark McCollough, USFWS, Orland, Maine. June 21, 2018.
Cameron, D. 2018. Maine Natural Areas Program, Augusta, Maine. Personal communication re: Multiple frequent, localized ice scour events caused a population decline of similar magnitude starting about 2011 from which there is no indication that lousewort populations have started to recover. To Mark McCollough, USFWS, Orland, Maine. July 17, 2018.
Cameron, D. 2018. Maine Natural Areas Program, Augusta, Maine. Personal communication re: Since the last population peak in 2011, the metapopulation has been declining at about 20 percent per year and has not rebounded as it did after previous catastrophic ice events in 1989 and 2003 To Mark McCollough, USFWS, Orland, Maine. August 9, 2018.
Cameron, S. A., J. D. Lozier, J. P. Strange, J. B. Koch, N. Cordes, L. F. Solter, and T. L. Griswold. 2011. Patterns of widespread decline in North American bumble bees. PNAS, January 11, 2011 108(2):662-667. www.pnas.org/cgi/doi/10.1073/pnas.1014743108
61
Species Status Assessment Report for the Furbish’s lousewort ● Version 1.1
Colla, S., and L. Packer. 2008. Evidence for decline in eastern North American bumblebees (Hymenoptera: Apidae), with special reference to Bombus affinis Cresson. Biodiversity and Conservation 17(6):1379-1391.
Dramstad, W.E. 1996. Do bumble bees (Hymenoptera: Apidae) really forage close to their nests? Journal of Insect Behavior. 9:163-182.
Environment Canada. 2010. Recovery Strategy for the Furbish’s lousewort (Pedicularis furbishiae) in Canada. Species at Risk Act Recovery Strategy Series. Environment Canada, Ottawa vi pp. + appendices.
Fernandez, I. J., C. Schmitt, E. Stancioff, S.D. Birkel, and A. Pershing. 2015. Maine’s Climate Future: 2015 Update. Climate Change Institute Faculty Scholarship. Paper 5. http://digitalcommons.library.umaine.edu/climate_facpub/5 last accessed August 13, 2018.
Franklin, I. R. 1980. Evolutionary change in small populations. In Conservation biology; an evolutionary-ecological perspective. Pages 135-150. Soule, M. E. and B. A. Wilcox. Sunderland- Sinauer.
Fowler, J. 1885. Preliminary list of the plants of New Brunswick. Bulletin of the Natural History Society of New Brunswick 4:8-84.
Furbish, K. 1881. A botanist’s trip to “The Aroostook.” American Naturalist 15: 469-470.
Furbish’s lousewort recovery team. 2006. Recovery strategy for Furbish’s lousewort (Pedicularis furbishiae) in New Brunswick. New Brunswick Department of Natural Resources. Fredericton, New Brunswick.
Gawler, S. C. 1981. Report on landowner contact program for Furbish’s lousewort in the St. John River valley, Maine. Unpublished report prepared for the U. S. Fish and Wildlife Service, Region 5, Newton Corner, Massachusetts. 71pp.
Gawler, S. C.1983. Furbish’s lousewort (Pedicularis furbishiae S. Wats) in Maine. Report prepared for the Maine Critical Areas Program of the State Planning Office. Planning Report Number 13. May 1983. Augusta, Maine.
Gawler, S. C., E. S. Menges, and D. M. Waller. 1983. 1983 Final report to The Nature Conservancy on population studies of Furbish’s lousewort, Pedicularis furbishiae S. Wats. The Maine Chapter of The Nature Conservancy, Brunswick, Maine.
Gawler, S. C, E. S. Menges, and D. M. Waller. 1986. Population biology of Furbish’s lousewort 1985 results. Holcomb Research Institute, Butler University, Indianapolis, Indiana. HRI Report Number 82. 53pp.
Gawler, S. C., D. M. Waller, and E. S. Menges. 1987. Environmental factors affecting the establishment and growth of Pedicularis furbishiae, a rare endemic of the Saint John River Valley, Maine. Bulletin of the Torrey Botanical Club. 114: 280-292. 62
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Gawler, S. C. 1988. Disturbance-mediated population dynamics of Pedicularis furbishiae S. Wats., a rare riparian endemic. Ph.D. Dissertation, University of Wisconsin, Madison. 195pp.
Gawler, S. C. and L. L. Gregory. 1994. Population sizes of Pedicularis furbishiae, Furbish’s lousewort, along the St. John River, Maine: 1993 census results. Report prepared for the U. S. Fish and Wildlife Service, Region 5. Maine Natural Areas Program, Department of Economic and Community Development, Augusta, Maine.
Gawler, S. C. and L. L. Gregory. 1998. Population sizes of Pedicularis furbishiae, Furbish’s lousewort, along the St. John River, Maine: 1997 census results. Report prepared for the U. S. Fish and Wildlife Service, Region 5. Maine Natural Areas Program, Department of Economic and Community Development, Augusta, Maine.
Gawler, S. C. and L. L. Gregory. 1999. Population sizes of Pedicularis furbishiae, Furbish’s lousewort, along the St. John River, Maine: 1999 census results. Report prepared for the U. S. Fish and Wildlife Service, Region 5. Maine Natural Areas Program, Department of Economic and Community Development, Augusta, Maine.
Gawler, S. C. and D. S. Cameron. 2001. Population Sizes of Furbish’s Lousewort (Pedicularis furbishiae) along the St. John River, Maine: 2001 Census Results. Report to the U.S. Fish and Wildlife Service. Maine Natural Areas Program, Department of Conservation, Augusta, Maine. 17 pp.
Gilpin M. E. and M. E. Soule. 1986. Minimum viable populations: processes of species extinction. Pages 19-34 in M. E. Soule, editor. Conservation Biology. Sinauer Associates, Sun- derland, Massachusetts, USA.
Gregory, L. L. and S. C. Gawler. 1990. Population sizes of Furbish’s lousewort, Pedicularis furbishiae 1980-1990. A report to the U. S. Fish and Wildlife Service, Endangered Species Program, Newton Corner, Massachusetts and the Critical Areas Program, Maine State Planning Office, Augusta, Maine. Maine State Planning Office report, Executive Department.
Gregory, L. L. and S. C. Gawler. 1992. Population sizes of Pedicularis furbishiae, Furbish’s lousewort along the St. John River, Maine. 1991 Census results. A report to the U. S. Fish and Wildlife Service Endangered Species Program, Newton Corner, Massachusetts and the Critical Areas Program, Maine State Planning Office, Augusta, Maine.
Grixti, J.C., L.T. Wong, S.A. Cameron, and C. Favret. 2009. Decline of bumble bees (Bombus) in the North American Midwest. Biological Conservation 142(1):75-84.
Harrison, S. and R. Noss. 2017. Endemism hotspots are linked to stable climatic refugia. Annals of Botany 119: 207−214.
Hatfield, R., S. Jepsen, R. Thorp, L. Richardson, and S. Colla, 2015. Bombus vagans. The IUCN Red List of Threatened Species 2015: e.T44938024A46440316.
63
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http://dx.doi.org/10.2305/IUCN.UK.2015-2.RLTS.T44938024A46440316.en. Downloaded on 31 July 2018.
Hayhoe, K., C. P. Wake, T. G. Huntington, L. Luo, M. D. Schwartz, J., S. Sheffield, E. Wood, B. Anderson, J. Bradbury, A. DeGaetano, T. J. Troy, and D. Wolfe. 2006. Past and future changes in climate and hydrological indicators in the U.S. Northeast. 2006 Climate Dynamics DOI 10.1007/s00382-006-0187-8. 32 pp.
Huntington, T. G., G. A. Hodgkins, B. D. Keim, and R. W. Dudley. 2004. Changes in the proportion of precipitation occurring as snow in New England (1949-2000). Journal of Climate 17:2626-2636).
IPCC. 2014. Climate Change 2014: Synthesis Report. Contribution of Work Groups I, II, and III to the Fifth Assessment Report of the Intergovernmental Panel on Climate Change [Core Writing Team, R.K. Pauchari and L.A. Meyer (eds.)] IPCC, Geneva, Switzerland, 151 pp.
Jacobson, G.L., I.J. Fernandez, P.A. Mayewski, and C.V. Schmitt (editors). 2009. Maine’s Climate Future: An Initial Assessment. Orono, ME: University of Maine.
Kartesz, J. T. and R. Kartesz. 1980. A synomized checklist of the vascular flora of the United States, Canada and Greenland. Volume II. The Biota of North America. University of North Carolina Press, Chapel Hill. 498pp.
Kim, J. and S. Jain. 2015. Wintertime high flow regime in northern Maine, USA: A hydroclimatic diagnostic study. CGU HS Committee on River Ice Processes and the Environment. 18th Workshop on the Hydraulics of Ice Covered Rivers, Quebec City, Province of Quebec, Canada.
Knight, M. E., A. P. Martin, S. Bishop, J. L. Osborne, R. J. Hale, A. Sanderson, and D. Goulson. 2005. An interspecific comparison of foraging range and nest density of four bumble bee (Bombus) species. Molecular Ecology 14:1811–1820.
Land Use Planning Commission 2012. St. John River resource protection plan. https://www.maine.gov/dacf/lupc/reference/resourceplans/prp_004_StJohnPlan_2012.pdf last accessed August 13, 2018.
Levin, D. A., 1975. Pest pressure and recombination systems in plants. American Naturalist 109:437-451.
Macior, L. W. 1978. The pollination ecology and endemic adaptation of Pedicularis furbishiae S. Wats. Bulletin of the Torrey Botanical Club 105:268–277.
Macior, L. W. 1979. Seedling development in Pedicularis furbishiae. Final Report to Committee on Research. University of Akron. Akron, Ohio. January 11, 1979. 4 pp.
Macior, L. W. 1980. Population ecology of the Furbish lousewort, Pedicularis furbishiae S. Wats. Rhodora 82(829):105-111. 64
Species Status Assessment Report for the Furbish’s lousewort ● Version 1.1
Macior, L. W. 1982. Plant community and pollinator dynamics in the evolution of pollination mechanics in Pedicularis (Scrophulariaceae). Pp. 29–45 in Pollination and evolution, eds. J. A. Armstrong, J. M. Powell, and A. J. Richards. Sydney, Australia: Royal Botanic Gardens.
Maine Natural Areas Program. 2003. A landowner’s guide to conservation of Furbish’s lousewort and the St. John River. Maine Natural Areas Program publication. Department of Conservation, Augusta, Maine.
Maine Natural Areas Program. 2015. Recovery efforts for Federally endangered and threatened plant taxa. 2015 Performance Report (Year 1 of 5). Maine Natural Areas Program, Maine Department of Agriculture, Conservation, and Forestry, Augusta, Maine.
Maine Natural Areas Program. 2017. Recovery efforts for federally endangered and threatened plant taxa. 2017 Performance Report (Year 3 of 5). Section 1: Population sizes of Pedicularis furbishiae, Furbish’s lousewort, along the St. John River, Maine: 2015-2015 census results. Donald Cameron, Maine Natural Areas Program, Department of Agriculture, Conservation, and Forestry, Augusta, Maine.
Manning, R. M. 1973. A study of the Dickey-Lincoln hydroelectric project and its impact on the resources of the upper Saint John River valley. Dickey-Lincoln School Lakes Project. 70. https://digitalcommons.library.umaine.edu/dickey_lincoln/70
Manomet Center for Conservation Sciences and National Wildlife Federation. 2013. The Vulnerabilities of Fish and Wildlife Habitats in the Northeast to Climate Change. A report to the Northeastern Association of Fish and Wildlife Agencies and the North Atlantic Landscape Conservation Cooperative. Manomet, Massachusetts.
McKenney, D. W., J. H. Pedlar, K. Lawrence, K. Campbell, and M. F. Hutchinson. 2007. Beyond traditional hardiness zones: using climate envelopes to map plant range limits. BioScience 57(11): 929-937.
Menges, E., S. C. Gawler and D. W. Waller. 1984. Studies into the population biology of the Furbish’s lousewort. 1983 Technical Report to the Maine Chapter of the Nature Conservancy, Brunswick, Maine.
Menges, E. S., S. C. Gawler, and D. M. Waller. 1985. Population biology of the endemic plant, Furbish’s lousewort (Pedicularis furbishieae), 1984 research. Report to the U. S. Fish and Wildlife Service. Newton Corner, Massachusetts. 126pp.
Menges, E. S., D. M. Waller, and S.C. Gawler. 1986. Seed set and seed predation in Pedicularis furbishiae, a rare endemic of the Saint John River, Maine. American Journal of Botany. 73:1168-1177.
Menges, E. S. and S. C. Gawler. 1986. Four-year changes in population size of the endemic Furbish’s lousewort: implications for endangerment and management. Natural Areas Journal 6(1):6-17. 65
Species Status Assessment Report for the Furbish’s lousewort ● Version 1.1
Menges, E. S. 1988. Conservation biology of Furbish’s lousewort. Final Report to Region 5, U. S. Fish and Wildlife Service. Holcomb Research Institute Report Number 126. Butler University, Indianapolis, Indiana. 61pp.
Menges, E. S. 1990. Population viability analysis for an endangered plant. Conservation Biology 4:52-62.
NatureServe. 2017. NatureServe Explorer: An online encyclopedia of life [web application]. Version 7.1. NatureServe, Arlington, Virginia. Available http://explorer.natureserve.org. (Accessed: May 9, 2018 ). (http://explorer.natureserve.org/servlet/NatureServe?searchName=Pedicularis+furbishiae
Nature Trust of New Brunswick. 2005. Assessing threats to the riparian flora of the Upper St. John River. Publication of the Nature Trust of New Brunswick, Inc., Fredericton, New Brunswick. 16 pp.
Olmstead, R. G., C. W. dePamphilis, A. D. Wolfe, N. D. Young, W. J. Elisons, and P. A. Reeves. 2001. Disintegration of the Scrophulariaceae. American Journal of Botany 88: 348–361.
Osborne, J. L., S. J. Clark, R. J. Morris, I. H. Williams, J. R. Riley, A. D. Smith, D. R. Reynolds, and A. S. Edwards. 1999. A landscape-scale study of bumble bee foraging range and constancy, using harmonic radar. Journal of Applied Ecology 36:519-533.
Province of New Brunswick. 2012. Watercourse and wetland alteration technical guidelines. Province of New Brunswick Department of Environment. Sustainable Development, Planning, and Impact Evaluation Branch. Fredericton, New Brunswick.
Piehl, M. 1963. Mode of attachment, haustorium structure, and hosts of Pedicularis canadensis. American Journal of Botany 50:978-985.
Rao, S. and J. P. Strange. 2012. Bumble Bee (Hymenoptera: Apidae) Foraging distance and colony density associated with a late-season mass flowering crop. Environmental Entomology, 41(4):905-915.
Riahi, K. S. Rao, V. Krey, C. Cho, V. chirkov, G. Fischer, G. Kindermann, N. Nakicenovic, and P. Rafaj. 2011. RCP8.5 – A scenario of comparatively high greenhouse gas emissions. Climatic change 109:33-57.
Richards, C. D. 1976. Report on rare and unusual plant species within Dickey-Lincoln project area. U. S. Army Corps of Engineers, Waltham, Massachusetts.
Richards, C. D. 1977. Report on survey of the St. John River, Maine and some of its major tributaries for Furbish’s lousewort, Pedicularis furbishiae and Josselyn’s sedge, Carex josselynii. Unpublished Report. Department of Botany and Plant Pathology, University of Maine, Orono, Maine.
66
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Richards, C. D. 1980. Report on monitoring populations of Furbish’s Lousewort, Pedicularis furbishiae, along the St. John River in northern Maine and New Brunswick during the summer of 1980. Report to USFWS, Region 5, Newton Corner, Massachusetts. 14pp.
Robart, B. W., C. Gladys, T. Frank, and S. Kilpatrick. 2015. Phylogeny and biogeography of North American and Asian Pedicularis (Orobanchaceae). Systematic Botany 40(1):229-258.
Rustad, L., J. Campbell, J. S. Dukes, T. Huntington, K. F. Lambert, J. Mohan, and N. Rodenhouse. 2012. Changing climate, changing forests: the impacts of climate change on forests of the Northeastern United States and Eastern Canada. General Technical Report NRS-99. Newtown Square, Pennsylvania: U. S. Department of Agriculture, Forest Service, Northern Research Station. 48pp.
Shaffer, M. L. and B. A. Stein. 2000. Safeguarding our precious heritage. Pages. 301-321. in Stein BA, Kutner LS, Adams JS, eds. Precious Heritage: The Status of Biodiversity in the United States . Oxford (UK): Oxford University Press.Shaffer
Shaffer, M.L. and B.A. Stein. 2000. Safeguarding our Precious Heritage. Pages 301–321 in B.A. Stein, L.S. Kutner, and J.S. Adams (eds.), Precious Heritage: The status of biodiversity in the United States. Oxford University Press. 399 pp.
Smithsonian Institution. 1975. Report on endangered and threatened plant species of the United States. Secretary, Smithsonian Institution, Washington, D. C., December 15, 1974. U. S. Government Printing Office, Washington, D. C.
Stirrett, G. M. 1980. Status report on the Furbish’s lousewort Pedicularis furbishiae. Committee on the Status of Wildlife in Canada, Ottawa, Ontario.
Tang, P. and S. Beltaos. 2008. Modeling of river ice jams for flood forecasting in New Brunswick. 65th Eastern Snow Conference. Fairlee, Vermont.
Toner, M. email dated November 21, 2017.
Town of Fort Kent. 2012. Comrehensive land use plan. Town of Fort Kent publication, Fort Kent, Maine. From http://www.fortkent.org/maps_forms_ordinances/ordinances/docs/2012_Comp_Plan_scanned_wi th_maps.pdf last visited August 8, 2018.
U.S. Fish and Wildlife Service 1983. The Furbish lousewort recovery plan. U.S. Fish and Wildlife Service. Newton Corner, Massachusetts. 31pp.
USFWS 1991. Furbish lousewort (Pedicularis furbishiae) revised recovery plan. Prepared by Susanna L. von Oettingen, New England Field Office, U. S. Fish and Wildlife Service, Concord, New Hampshire.
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U.S. Fish and Wildlife Service 2007. Furbish’s lousewort (Pedicularis furbishieae) Five-Year Review: Summary and Evaluation. Mark McCollough, author, U. S. Fish and Wildlife Service, Maine Field Office, Old Town, Maine.
U.S. Fish and Wildlife Service 2016. USFWS Species Status Assessment Framework: an integrated analytical framework for conservation. Version 3.4 dated August 2016. 21 pp.
U.S. Department of the Interior 2018. U.S. Department of the Interior strategic plan for fiscal years 2018-2022. U.S. Department of the Interior, Washington, D.C. https://www.doi.gov/sites/doi.gov/files/uploads/fy2018-2022-strategic-plan.pdf last accessed August 9, 2018.
U. S. Global Change Research Program (USGCRP) 2017: Climate Science Special Report: Fourth National Climate Assessment, Volume I [Wuebbles, D.J., D.W. Fahey, K.A. Hibbard, D.J. Dokken, B.C. Stewart, and T.K. Maycock (eds.)]. U.S. Global Change Research Program, Washington, DC, USA, 470 pp. https://science2017.globalchange.gov/chapter/executive- summary/ last accessed August 14, 2018.
U. S. Geologic Survey. 2017a. National climate change viewer. Tutorial and documentation. Hostetler, S.W. and Alder, J.R., 2016. Implementation and evaluation of a monthly water balance model over the U.S. on an 800 m grid. Water Resources Research, 52, doi:10.1002/2016WR018665. Thrasher, B., J. Xiong, W. Wang, F. Melton, A. Michaelis, and R. Nemani, 2013. New downscaled climate projections suitable for resource management in the U.S. Eos, Transactions American Geophysical Union 94, 321-323, doi:10.1002/2013EO370002. U. S. Geological Survey, Washington, D.C.
U. S. Geologic Survey. 2017b. Climate Research and Development Program National Climate Change Viewer. Summary of upper St. John River valley, Maine (10180006). Available at http://www.usgs.gov/climate_landuse/clu_rd/nccv/viewer.asp Accessed on March 17, 2016.
U. S. Geologic Survey 2018. Water Data Reports 2008 – 2017, 01010500 ST. John River At Dickey, ME. https://waterdata.usgs.gov/nwis/wys_rpt/?site_no=01010500&agency_cd=USGS, accessed 9/24/2018.
Vose, R.S., D.R. Easterling, K.E. Kunkel, A.N. LeGrande, and M.F. Wehner, 2017: Temperature changes in the United States. In: Climate Science Special Report: Fourth National Climate Assessment, Volume I [Wuebbles, D.J., D.W. Fahey, K.A. Hibbard, D.J. Dokken, B.C. Stewart, and T.K. Maycock (eds.)]. U.S. Global Change Research Program, Washington, DC, USA, pp. 185-206, doi: 10.7930/J0N29V45. https://science2017.globalchange.gov/chapter/executive- summary/ last accessed August 14, 2018.
Waller, D. M., D. M. O’Malley, and S. C. Gawler. 1987. Genetic variation in the extreme endemic Pedicularis furbishiae (Scrophulariaceae). Conservation Biology 1: 335–340.
Waller, D. M., D. M. O’Malley, and S. C. Gawler. 1988. Genetic variation in the extreme Pedicularis furbishiae (Scrophulariaceae). Conservation Biology 1: 335-340.
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Williams, P., S. Colla, and Z. Xie. 2009. Bumblebee vulnerability: common correlates of winners and losers across three continents. Conservation Biology 23(4):931-940.
Wolf, S. and R. F. A. Moritz. 2008. Foraging distance in Bombus terrestris (Hymenoptera: Apidae). Apidologie 38:419-427.
Wroblewska, A. and P. Mirski. 2018. From past to future: impact of climate change on range shifts and genetic diversity patterns of circumboreal plants. Regional Environmental Change 18:409-424.
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Glossary Alleles Basal rosette Broomrape Calcareous Circumneutral Climate envelope Colonization, colonize Connectivity Cross-pollinated Dehisce Demographic Effective population size Endemic Fecundity Fitness Genetic bottlenecks Genetic drift Glacial till Haustoria Hemiparasite Heterozygosity Hydrodynamics Inbreeding depression Inflorescence Lacustrine Lambda Metapopulation Minimum viable population Niche Outcrosser, outcrossing Perennial Plant hardiness zones Recruitment Seed bank Seed capsules Shade tolerant Snapdragon Stage-based metrics Stochastic models Survival Vegetative plant
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Appendix 1. Table 4. Maine shoreland zoning regulations near Furbish’s lousewort habitat
Furbish’s lousewort Zoning standard Forestry standards subpopulations Upriver of LUPC P-RP004 -250-foot zone Allagash; Irving, subdistrict, St. John - no clearcutting within 50 feet of river Orion Timberlands, Resource Protection - >50 feet, no openings > 0.3 acre Seven Islands Plan16 - harvest no more than 40 percent in 250-foot zone in 10-year period - no new development Upriver of Maine Forest -250-foot zone Allagash; Prentiss Service - no clearcutting within 50 feet of river & Carlisle PRR/RP/SL1 ->50 feet, no openings >0.3 acre Recreation Resource - harvest no more than 40 percent in 250-foot zone in Protection 10-year period subdistrict,17 Subpopulations in Maine mandatory -250-foot zone organized towns shoreland zoning; - various development districts, piers and docks, minimum allowed within the 250-foot zone; 100-foot setback for standards18 new buildings, roads, gravel mining; 75-foot setback for agriculture, septic systems; removal of vegetation (including trees) permitted - harvest no more than 40 percent of total volume in 10- year period; maintain “well-distributed” stand of trees; ->75 feet, no openings >0.3 acre -forest roads >100 feet Unorganized towns LUPC P-SL1 -250-foot zone of Saint John Protection shoreland - no clearcutting within 50 feet of river Plantation and subdistrict19 D-GN, ->50 feet vegetated buffer, no forest openings >0.3 acre Hamlin DRS – general and - harvest no more than 40 percent in 250-foot zone in residential 10-year period development - agriculture 50-foot buffer; new building 100-foot setback
16 Maine Land Use Planning Commission (2012) https://www.maine.gov/DACF/lupc/reference/resourceplans/prp_004_StJohnPlan_2012.pdf last accessed July 11, 2018. 17 Maine Forest Service Rules, Standards for Timber Harvesting and Timber Harvesting Related Activities within Unorganized and Deorganized Areas of the State, Chapter 27 04-058 https://www.maine.gov/DACF/mfs/publications/rules_and_regs/chap_27_rules.pdf last accessed July 11, 2018. 18 Chapter 1000 Guidelines for Municipal Shoreland Zoning Ordinances Title 38, Chapter 3, §§ 435-449 https://www.maine.gov/DACF/mfs/publications/rules_and_regs/chap_27_rules.pdf last accessed July 11, 2018. 19 Chapter 10 Land Use Planning Commission, Sub-chapter III. Land Use Standards https://www.maine.gov/dacf/lupc/laws_rules/rule_chapters/Ch10_SubchapterIII.pdf last accessed July 12, 2018. 71
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Appendix 2. Census counts of Furbish’s lousewort in New Brunswick and Maine.
Summary of survey results for Furbish’s lousewort. Counts of Furbish’s lousewort from complete and partial surveys (1977-2018). Numbers in parenthesis represent the proportion of plants in flower/plants not in flower.
Source Aroostook Above Stirrett Medford Big Flat Grand Preserve Falls 1977 Hinds (1998) 178 254 70 (63/115) (44/26)
1979 Stirrett 33 254 115 (1980) (154/100) (69/46)
1981 Brown 80 102 212 (1982)
1982 Brown 125 117 213 (1982)
1983 from 231 125 175 Drummond (1997)
1984 Brown for 234 225 DNRE in Hinds (1988) 1987 171 120 165 (Drummond, (50/121) (41/79) DNRE)
1991 O’Brien 50+ 313+ (12/38) (112/201)
1996 O’Brien 136 (1997) (90/37)
1997 Hinds (1998) 22 62 (18/4) (12/50) 1998 DNRE 67 50
1999 DNRE 42 171* 651 database (42/0) (31/3) 1 O’Brien (1999)
2000 DNRE 84 62 database 72
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2001 DNRE 314 298 146 database (163/151) (115/183) (73/73)
2002 Nature 224 243 126 187 124 Trust (97/127) (105/138) (66/15) (61/126) (99/25) (Nature Trust 2003) 2006 388a 46a 62b a- NBDNR & (36/10) NTNB (mid June) b -NBDR & NBPower (Aug)
2007 NBDNR, 241 43 68 NBPower &NTNB (late May) 2008 R. Fournier 198 68 41 204 48 (early June) 2014 Gart Bishop 20 62 5 36 35 for Env. Canada 2018 ACCDC 2 70 1 64 20 Atlantic Canada Conservation Data Center
Notes: * Note: the 1999 total for above Grand Falls was obtained from a survey in July, while the numbers in parenthesis represent the plants that were resurveyed in a more limited August visit.
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2-yr FLOWERING STEM NUMBERS change EO 02- 04- 06- 08- 10- 12- 14- 16- Surveysite Town EO # RS #s 1980 1984 1989 1991 1993 1995 1997 1999 2001 03 05 07 09 11 13 15 17 raw % Blue Brook D.S. T14R14 44 ------101 232 176 82 78 -4 -5% T13/T14 Townline T14R13 46 ------335 401 331 225 92 -133 -59% Basford Rips Upstream T14R13 45 ------187 88 281 250 330 108 192 84 78% Basford Rips T15R13 33 1.1+1.3 1 ------50 66 23 115 113 38 123 88 46 259 169 106 198 113 -85 -43% Big Black jxn & NW Shore T15R13 9 1.4+2+3.1 86 407 369 302 301 112 141 115 59 151 38 96 105 316 196 268 288 20 7% Camp 107 - Stewart Brk. T15R13 15 3.2+3.3 65 179 112 75 55 129 219 102 58 281 66 202 123 58 40 63 18 -45 -71% Seminary Brook T15R13 25 3.4+4+5.1 --- 163 26 123 102 72 23 43 18 57 112 101 56 nc 46 45 39 -6 -13% Unnamed Rapids #2 T15R13 29 5.2+5.3 --- 188 27 247 153 117 375 94 85 178 189 188 104 88 85 55 88 33 60% Long's Rapids upriver (N) T15R13 35 5.9 ------42 NC NC nc nc nc nc 88 117 105 162 128 -34 -21% Long's Rapids downriver (N) T16R12 34 6.9 ------146 33 8 NC nc nc nc nc 129 142 125 167 50 -117 -70% Castonia Farm T16R12 3 7.1+7.2 228 50 0 158 132 195 381 124 88 109 32 53 31 113 121 141 138 -3 -2% Schoolhouse Rapids T16R12 36 7.9 6 0 0 0 NC NC nc nc nc nc 42 103 121 22 17 -5 -23% Ouellette Farm upriver T16R12 39 8 --- 152 179 229 105 134 116 122 141 101 51 11 27 10 15 nc NA NA Ouellette Farm downriver T16R12 30 9.1 --- 213 397 462 204 287 796 434 357 373 255 130 260 172 119 121 86 -35 -29% Fox Brook Rapids T16R12 31 9.2+9.3 --- 366 84 14 1 80 152 156 81 181 241 161 179 66 50 24 50 26 108% Fox Brook Ledges T16R12 2 10.9 --- 27 18 12 15 11 2 4 0 nc 5 nc nc nc nc NA NA Hafford Brk- N ALLAGASH 4 11.9 65 71 3 109 4 NC? nc 4 nc nc nc 1 nc nc nc nc NA NA Poplar Island Rapids ALLAGASH 28 12 11 ------SC SC NC nc nc nc nc 315 624 536 302 164 -138 -46% Campbell Brk - Walker ALLAGASH 27 15.1 ------45 39 34 23 17 108 54 nc 11 nc 496 585 174 106 142 36 34%
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Brk
Big Rapids ALLAGASH 1 15.2+15.3+16 263 18 75 56 2 5 34 67 172 310 2 nc 44 65 74 39 1 -38 -97%
2-yr FLOWERING STEM NUMBERS change EO Surveysite Town EO # RS #s raw % Dickey Bridge ALLAGASH 6 18 161 204 277 34 4 37 29 73 15 9 6 0 25 55 47 49 37 -12 -2 St Paul's Church D.S. ALLAGASH 14 20 378 346 725 142 228 297 809 1091 1324 1226 295 452 96 217 100 143 191 48 3 Allagash Delta ALLAGASH 17 21 ------187 192 19 114 50 29 175 199 31 2 nc nc 0 nc nc NA NA Pelletier Brook ALLAGASH 8 22+23 603 512 243 109 34 5 28 35 35 5 0 0 0 0 0 nc nc NA NA Casey Brook - Cross Rock ALLAGASH 5 24+25+26+27+28 1598 916 870 120 44 49 152 747 629 1230 115 195 32 340 252 182 76 -106 -5 Wiggins ST. Brook FRANCIS 7 30 38 84 321 1 13 20 29 48 24 62 11 3 0 nc 0 nc nc NA NA Rankin ST. Rapids FRANCIS 19 33 132 104 453 41 0? 50 96 5 94 312 284 97 0 nc nc nc nc NA NA Thibideau ST. Brook FRANCIS 18 35 143 351 373 144 127 311 273 355 193 67 23 13 1 nc 0 nc nc NA NA St. Francis ST. Line FRANCIS 11 37 414 156 950 128 100 202 320 295 178 195 38 2 4 nc 0 nc nc NA NA Camel FORT Brook KENT 20 40 649 447 1111 89 112 172 418 396 411 368 273 225 118 80 41 27 13 -14 -5 Van VAN Buren BUREN 21 43 21 5 0 3 4 0? 0 nc nc nc 0 nc nc nc 0 NA NA Hamlin HAMLIN 23 44 33 49 18 7 5 23 26 39 51 41 nc nc 19 nc 7 0 nc NA NA Hamlin Corners HAMLIN 42 310 247 390 257 239 -18 - Totals 4895 4856 6836 3024 2021 2447 4617 4587 4269 5618 2398 2105 3570 4467 3582 2801 2240 -561 -2
Table 1. Flowering stem numbers, 1980- 2017. Sites are in upriver to downriver order. "nc" = not counted. Shading distinguishes the four River Sections used for recovery goal criteria (i.e., page 1 of table is all River Section 1).
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Appendix 3. Terminology used to express uncertainty in the Furbish’s lousewort SSA. This terminology is specified by The International Panel on Climate Change (IPCC)(IPCC 2007) in their report on climate change. They provide two tables, one for confidence terminology (see Table 6), and one for likelihood terminology (see Table 7). These tables are often adopted in the environmental science literature. From U. S. Fish and Wildlife Service. 2018. Species Status Assessment Report-Writing Prompt Book. Unpublished Document. Table 1. Confidence Terminology (IPCC, 2007, Uncertainty Guidance Note, p. 3) Degree of confidence in Confidence Terminology being correct Very high confidence At least 9 out of 10 chance
High confidence About 8 out of 10 chance
Medium confidence About 5 out of 10 chance
Low confidence About 2 out of 10 chance
Very low confidence Less than 1 out of 10 chance
Table 2. Likelihood Terminology (IPCC, 2007, Uncertainty Guidance Note, p. 4) Likelihood of the occurrence/ Likelihood Terminology outcome
Virtually certain > 99% probability
Extremely likely > 95% probability
Very likely > 90% probability
Likely > 66% probability
More likely than not > 50% probability
Other terminology related to confidence and common to other Species Status Assessments. Confidence Explanation Terminology
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We are more than 90% sure that this relationship or assumption accurately reflects the reality in the wild as Highly Confident supported by documented accounts or research and/or is strongly consistent with accepted conservation biology principles.
We are 70 to 90% sure that this relationship or assumption accurately reflects the reality in the wild as Moderately Confident supported by some available information and/or is consistent with accepted conservation biology principles.
We are 50 to 70% sure that this relationship or assumption accurately reflects the reality in the wild as Somewhat Confident supported by some available information and/or is consistent with accepted conservation biology principles.
We are less than 50% sure that this relationship or assumption accurately reflects the reality in the wild because no supporting available is information and/or Not Confident uncertainty exists about the consistency with accepted conservation biology principles. Indicates areas of high uncertainty.
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