Conservation Agreement for the Oregon Spotted Frog (Raila Pretiosa) in the Klamath Basin of Oregon

Conservation Agreement for the Oregon Spotted Frog (Raila pretiosa) in the Klamath Basin of Oregon

U.S. Fish and Wildlife Service Fremont-Winema National Forests Lakeview District ofthe Bureau ofLand Management Medford District ofthe Bureau ofLand Management Klamath Marsh National Wildlife Refuge

I. SPECIES ADDRESSED

Rana pretiosa (Oregon spotted frog)

II. INVOLVED PARTIES

U.S. Fish and Wildlife Service USDA Forest Service Laurie Sada, Field Supervisor J. Richard (Rick) Newton, Acting Forest Supervisor Klamath Falls Fish and Wildlife Office Fremont-Winema National Forests 1936 California Avenue 1301 S. G Street Klamath Falls, OR 97601 Lakeview, OR 97630 (541) 885-8481 (541) 947-6256 Attn: Trisha Roninger Attn: Amy Markus

Bureau ofLand Management Bureau ofLand Management Carol Benkosky, District Manager Tim Reuwsaat, District Manager Lakeview District Medford District 2795 Anderson Avenue, Bldg. #25 3040 Biddle Road Klamath Falls, OR 97603 Medford, OR 97504 (541) 883-6916 (541) 618-2200 Attn: Rob Roninger Attn: Steve Godwin

Klamath Marsh National Wildlife Refuge Ron Cole, Project Leader Klamath Basin National Wildlife Refuge Complex 4009 Hill Road Tulelake, CA 96134 (541) 783-3380 Klamath Marsh Refuge Office (530) 667-2231 Klamath Complex Office Tulelake Attn: Faye Weekley

1 III. AUTHORITY, PURPOSE, OBJECTIVES, AND GOALS

A. Authority The authority to enter into this voluntary Conservation Agreement derives from the Endangered Species Act (Act) of 1973, as amended; the Fish and Wildlife Act of 1956, as amended; and the Fish and Wildlife Coordination Act of 1934, as amended.

B. Purpose The purpose ofthis Conservation Agreement is to fonnally document the intent ofthe parties involved to protect and contribute to the conservation ofthe Oregon spotted frog by implementing conservation actions for the species and its habitat on federal lands in the Klamath Basin of Oregon. This Conservation Agreement is not a decision document or fonnal direction for the federal agencies. Rather, it is intended to guide strategic planning, project development, management, conservation actions, and research studies for Oregon spotted frog in the Klamath Basin.

C. Goals and Objectives The goal ofthis agreement is to provide a means for the protection and conservation ofthe Oregon spotted frog in the Klamath Basin ofOregon. This agreement is not intended to provide site specific infonnation, but rather to include broad-scale infonnation, goals, and conservation actions for Oregon spotted frog conservation in the Klamath Basin.

The objectives ofthis agreement are to: I) manage occupied habitat in a manner that sustains and/or restores its ability to support Oregon spotted frog populations; 2) stabilize or increase populations within the Klamath Basin; 3) reduce threats; and 4) increase distribution among available suitable habitats by restoring or creating habitat.

IV. INTRODUCTION

This agreement includes a brief summary and overview ofthe Oregon spotted frog, including a species description, and a description ofthe Oregon spotted frog's habitat, life history, distribution, status, as well as threats facing the species range-wide and in the Klamath Basin. This includes both information based on available credible research and the professional opinion offederal wildlife biologists. This information may need to be updated as new science becomes available. For more detailed infonnation regarding Oregon spotted frog, refer to the Conservation Assessment for the Oregon spotted frog (Rona pretiosa) (Cushman and Pearl 2007), which is incorporated by reference.

For federal Oregon Bureau ofLand Management (BLM) lands in Oregon, the Special Status Species policy details the need to manage for species conservation. Conservation is defined as the use ofall methods and procedures which are necessary to improve the condition of Special Status Species and their habitats to a point where their Special Status recognition is no longer warranted. In addition, implementation ofthe policy is intended to ensure that actions funded, authorized, or carried out by the BLM do not contribute to the need to list species under the Endangered Species Act.

2 For the Pacific Northwest Region ofthe USDA Forest Service, the Sensitive Species policy requires the Agency to maintain viable populations ofall native and desired non-native wildlife, fish, and plant species in habitats distributed throughout their geographic range on national forest system lands. Management should also preclude a trend towards federal listing, for any identified Sensitive Species.

For the U. S. Fish and Wildlife Service (USFWS), the Endangered Species Act (Section 4(b)(1)(A)) provides an avenue for the U. S. Fish and Wildlife Service to enter into voluntary agreements that benefit species which are under evaluation for listing under the Act. These agreements are intended to further the purposes ofthe Act by supporting actions that may improve the status ofan individual species and which may preclude the need to list the species.

V. STATUS AND DISTRIBUTION OF SPECIES

A. Species Description The Oregon spotted frog is the most aquatic ranid frog in western North America (Leonard et al. 1993). The back usually has black spots or rings with uneven edges and light centers (Leonard et al. 1993, Corkran and Thoms 1996). The belly and groin region display a mottled wash ofred to orange in adults, but coloration in juveniles can be absent or occur over small portions ofunderside ofthighs or groin (Hayes 1998). The eyes are upturned relative to other Northwestern native frogs, and the feet can be fully webbed (Corkran and Thoms 1996). Hind legs are relatively short compared to body length. Eggs are laid in fist sized spherical masses containing 300 to 1500 embryos. Tadpoles are brown or gray with gold flecks, and the tail is about twice the body length (Leonard et al. 1993, Corkran and Thoms 1996).

B. Habitat Description Oviposition sites tend to be close to shore in shallow water, and are usually positioned above vegetated, gently-sloped substrates (Pearl et al. 2009) Eggs are generally laid above sedges, grasses, and rushes in early spring before plant growth has begun (Pearl et al. 2009). Post breeding habitats used by Oregon spotted frogs are typically aquatic, and often have areas of floating, emergent or submergent vegetation that is near refuge that can be used to escape predators. One study in Oregon found that egg mass numbers were positively related to the presence ofother Oregon spotted frog breeding sites nearby and the amount ofemergent and subemergent vegetation coverage (Pearl et aI. 2009). Habitats used during winter include flowing channels and springs (Shovlain 2005, Chelgren et al. 2008).

Based on a telemetry study at one lowland site in western Washington, Watson et al. (2003) summarized seasonal requirements for Oregon spotted frogs as: 1) stable, shallow water for egg and tadpole survival in the breeding season; 2) deep, moderately vegetated pools for adult and juvenile survival in the dry season; and 3) shallow water levels over emergent vegetation for protecting all age classes dming the cold weather in the wet season.

3 C. Life History Oregon spotted frogs typically oviposit communally and these aggregations can contain eggs from 100 or more females in larger populations (Pearl et al. 2009). Communal oviposition may be linked to the female's affinity for depositing egg masses on top ofpreviously laid egg masses (Licht 1969). Licht (1969) reported that initial breeding activity from one low elevation site in British Columbia began when air temperatures were at least 5° Celsius (4 I°Fahrenheit). However, the trigger for breeding is not well understood and is likely to vary geographically and with elevation (c. Pearl, pers. comm).

High breeding site fidelity is suspected because oviposition often occurs within 0.5 m (20 in) ofprevious years locations (Licht 1969). Use oftraditional oviposition sites that may have limited availability because ofunique characteristics, and the possibility that adults may have limited flexibility to switch sites, makes the Oregon spotted frog particularly vulnerable to habitat changes at oviposition sites (Hayes 1994).

Several aspects ofthe Oregon spotted frog's life history have been proposed as contributing to the species' vulnerability to habitat alterations (Hayes 1994, 1997, Watson et al. 2003, Pearl et al. 2004, Cushman and Pearl 2007, Pearl et al. 2009): 1) communal egg laying at sites used year after year restricts the number ofreproductive sites; 2) the species' warm water requirement results in habitat overlap with introduced warm water fish; 3) the active season warm water requirement may limit suitable habitat in the cool climates ofthe Pacific Northwest; 4) the species may be vulnerable to the potential loss or alteration ofsprings used for overwintering; and 5) changes that increase deep, permanent water components are likely to favor establishment ofnon-native bullfrogs and fish, both ofwhich may be detrimental to Oregon spotted frogs.

D. Distribution The species is currently known from less than 50 population complexes in southwestern British Columbia, western and south-central Washington, and western, central, and south central Oregon; no populations are known to persist in California (Cushman and Pearl 2007). Revisits ofhistoric localities led Hayes (1997) to conclude that the species may be lost from 70 to 90% ofits historic range.

Most ofthe extant sites in the Klamath Basin are relatively higher in elevation and maintain the least altered hydrology (Hayes 1997). These sites also have the fewest exotic aquatic predators when compared to historic sites (Hayes 1997). In general, habitat modifications and aquatic predators have been more substantial at lower elevations than higher elevations, suggesting that either one or a combination may be responsible for the failure to record the species at lowland historical sites (Hayes 1997).

E. Status The Oregon spotted frog is considered a Candidate species by the U.S. Fish and Wildlife Service. Candidate species are plants or animals for which the USFWS has sufficient information on their biological status and threats to propose them as endangered or threatened under the Endangered Species Act but for which. development ofa proposed listing regulation is precluded by other higher priority listing activities.

4 The Oregon spotted frog is ranked as Sensitive-Critical by Oregon Department ofFish and Wildlife; a Special Status Species by Oregon BLM; and Sensitive by the Pacific Northwest Regional Forester's Special Status Species List. The Oregon Natural Heritage Information Center gives the Oregon spotted frog a Global rank ofG2 (globally imperiled because of rarity); a National rank as N2 (taxa that are threatened with extirpation or presumed to be extirpated in the United States); a State rank ofS2 (taxa that are threatened with extirpation or presumed to be extirpated from the state ofOregon). The Oregon Natural Heritage Information Center also classifies the Oregon spotted frog on List I which means the species is threatened with extinction or presumed to be extinct throughout their entire range; these are the taxa most at risk, and should be the highest priority for conservation action.

VI. THREATS FACING THE SPECIES: RANGE-WIDE AND KLAMATH BASIN

The information below provides an overview ofthreats to the species both range-wide and within the Klamath Basin. Much ofthe literature cited below on Oregon spotted frogs derives from British Columbia, Washington, and Deschutes Basin in Oregon. Genetic data suggest that the Klamath Basin populations form a group that differs from population segments in other portion ofthe species range (Blouin 2000). Absent information comparing the Klamath genetic unit to other population segments, caution should be exercised when extrapolating information from other areas to Klamath Basin populations.

In general, there is little information on the prevalence and magnitude ofthreats to Oregon spotted frogs in the Klamath Basin. More importantly, the relative importance ofeach stressor and the potential for interaction amount multiple stressors is not well understood. One study recognized evidence that Oregon spotted frog populations in the Klamath Basin may be at greater risk than those in the upper Deschutes basin: I) surveys in 2006 found fewer egg masses in the Klamath breeding ponds; 2) there are greater distances and more modified lands between known sites in the Klamath; and 3) among the sites that have more than 5 years ofmonitoring data, the only one with a clear declining trend is in the Klamath Basin (Jack Creek) (Pearl et aI. 2009).

A. Loss and Alteration ofWetland Habitat

Range-wide Twenty-one oftwenty-eight Oregon spotted frog sites (75%) assessed in the mid-1990's have some human-related hydrological alterations (Hayes 1997, Pearl 1999). Noted modifications ranged from minor (e.g. local ditching around springs) to substantial changes, including major modifications ofhistoric flow patterns (Hayes 1997, Pearl 1999) resulting in loss of wetland habitat. Hydrologic changes have also resulted in a reduction in the natural disturbance regimes that historically created habitat for Oregon spotted frog such as fluvial cutting and meanders ofstreams and rivers and the creation ofponds and open water conditions by beaver. Studies also suggest that wetland loss and modification may provide conditions that favor non-native exotic fish and bullfrogs (Adams 1999, Maret et aI. 2006, Adams and Pearl 2007).

5 Fluctuating water levels at critical periods in the Oregon spotted frog's life cycle, whether natural or human-induced, may negatively affect the species. Due to the tendency for communal oviposition, water level reduction during the 2-3 week window when eggs are developing can result in the loss ofsignificant portions ofthat year's reproductive effort. Reduction in water levels may expose larval and post-metamorphic Oregon spotted frogs to predation as a result ofreducing cover and confining the frogs to smaller areas. Large increases in current or water level can be detrimental for egg masses ifthey become submerged or drift to unfavorable locations (Garwood et al. 2008).

Klamath Basin Extensive wetland draining, mainly for agricultural purposes, has occurred in the Klamath Basin starting in the late 1800's and continuing through the 1970's. The hydrology ofthe Upper Klamath and Agency Lakes, as well as other areas in the Klamath Basin, have been significantly changed by extensive diking and draining ofseasonal wetlands, by water diversions from tributaries, by diverting water out ofthe lakes, and by the construction ofa dam at the lakes outlet in 1921 that allowed the lake to be operated as a storage reservoir (DEQ 2002).

Akins (1970) did the first comprehensive analysis ofthe basin's wetlands. He estimated 2 there were originally 350,000 acres (1,400 km ) ofwetlands in the upper basin, that private 2 2 farming modified 50,000 acres (200 km ), and that another 200,000 acres (800 km ) were affected by drainage within the Klamath Project. The Klamath Project was developed by the Bureau ofReclamation in the early part ofthe 20th century (Foster 2002). Largely based on the analysis by Atkins, other authors reported estimates ofwetlands losses in the upper basin of65 to 90 percent (e.g., Bottorff1989; Gearhart et al. 1995; NRCS 2006).

Hydrologic modifications at occupied Oregon spotted frog locations in the Klamath Basin range from minor changes to major modification ofhistoric flow patterns. In addition, the diversion ofwater for agricultural purposes can result in an annual variation ofwater levels that can negatively impact Oregon spotted frog, particularly during the larval and post metamorphic life stages.

Wetlands losses in the basin have slowed and there are numerous restoration activities occurring throughout the Klamath Basin. For example, the Natural Resources Conservation Service reported that as of2007, 8,900 acres ofwetlands were restored for fish and wildlife habitat and 21,000 acres enrolled into the Wetlands Reserve Program (NRCS 2007). In addition, the proposed Klamath Basin Restoration Agreement may lead to additional rehabilitation efforts and partnership opportunities to benefit watershed function and aquatic ecosystems throughout the Klamath Basin.

B. Plant Succession and Other Vegetative Changes

Range-wide Succession by native and non-native vegetation has the potential to modify conditions at wetlands associated with Oregon spotted frog habitat (Cushman and Pearl 2007). Threats

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exist from exotic plant invasions, such as reed canarygrass (Phalaris arundinacea). Aggressive exotics can completely alter the structure ofwetland environments and can create dense areas ofvegetation that may be unsuitable as Oregon spotted frog habitat (McAllister and Leonard 1997).

Succession (changes in plant communities) may be a factor threatening many Oregon spotted frog sites. Fire, beaver, and active floodplain meanders were natural disturbances that were historically more common within Oregon spotted frog habitat, and acted to periodically create open water habitat (Cushman and Pearl 2007).

Klamath Basin At some locations occupied by Oregon spotted frog (e.g. Klamath Marsh), the lack of disturbance to vegetation is resulting in a transition ofopen water habitat to solid stands of bulrush, cattail, or sedge (C. Damberg pers. com 2008). Fire, grazing, and haying operations that historically occurred in these areas on a more frequent basis are no longer causing the necessary disturbance to set back plant succession (C. Damberg pers. com. 2008). In some cases, grazing or haying for biological reasons may benefit Oregon spotted frog habitat by opening the vegetation (C. Damberg pers. com 2008). Historically, it is expected that beaver played an important role in managing vegetation and creating open water conditions and ponds in the Klamath Basin.

Lodgepole pines and other tree and shrub species are encroaching on wetland habitats occupied by spotted frogs at several sites in the Klamath Basin. It is suspected that lodgepole encroachment adjacent to known breeding habitat could result in shading ofthe water (A. Markus pers. obs. 2009). The effects ofthis are not well understood, and merit more attention. Local vegetation changes, in particular the increase ofwoody vegetation such as lodgepole pine or willow, have the potential to affect frog habitat by altering base flows, isolation, evaporation and transpiration, or patterns ofsnow and ice accumulation or thaw.

C. Interactions with Non-native Fishes and American Bullfrogs

Range-wide There are a number ofdocumented and potential predators ofOregon spotted frogs. Several introduced fish, as well as American bullfrogs (Rana catesbeiana [=Lithobates catesbeianus]), have been transplanted into the Oregon spotted frogs' historic range and may have contributed to the decline ofthis and other native frogs around the western USA (Hayes and Jennings 1986, Kiesecker and Blaustein 1998, Pilliod and Peterson 2001, Pearl et al. 2004, Vredenberg 2004).

Bullfrogs have been introduced into the Pacific Northwest from eastern North America. Bullfrogs are thought to possess several ecological advantages over northwestern ranid frogs: 1) post-metamorphic bullfrogs can attain much larger body sizes (and thus eat larger food items) than Oregon spotted frogs in most habitats in the Pacific Northwest (Pearl et al. 2004); 2) bullfrogs do well and may even benefit from introduced fish that present a direct threat to native northwestern ranids, in part because bullfrog tadpoles are not palatable to many ofthe eastern fish that have been introduced in the west (Kruse and Francis 1977, Adams et al.

7 2003); 3) larval bullfrogs overwinter at least once and reach sizes exceeding spotted frogs (and most other western native frogs); bullfrog tadpoles can physically displace native tadpoles from shallows that are wanner and offer refuge from fish predators (Kiesecker and Blaustein 1998); and 4) bullfrog tadpoles are more resistant to the effects ofpesticides and heavy metals than other ranid frogs (Hayes and Jennings 1986).

Data also exist to suggest facilitative interactions between habitat modifications that increase permanence and exotic fish and bullfrogs (Adams 1999, Maret et al. 2006, Adams and Pearl 2007). Thus, these issues should not be treated independently. For example, non-native fish can influence bullfrog tadpole survival by preying upon one oftheir primary predators, dragonfly nymphs (Adams et al. 2003). This relationship implies that reducing the distribution and abundance ofnon-native fish has the potential to reduce survival ofbullfrog tadpoles (Adams et al. 2003).

The widespread introduction ofnon-native fish has affected many amphibians native to lentic habitats ofwestern North America (Adams 1999, Pilliod and Peterson 200I, Pearl et al. 2005, Vredenberg 2004). Oregon spotted frogs, which are palatable to fish, did not evolve with these introduced species and may not have the mechanisms to avoid fish that prey on the tadpoles ofnative amphibians. In a study that assessed the broad status ofthe species and potential influences ofhabitat and stressors on population size, the number of egg masses at a pond was negatively associated with non-native fish access to potential overwintering habitat (Pearl et aI., 2009). Brook trout are the most frequently recorded introduced predator at a subset ofOregon spotted frog sites in Oregon (Hayes 1997). Oregon spotted frog can persist at some sites with introduced fish, however the mechanisms that allow coexistence are not understood.

Klamath Basin Exotic aquatic predators are widespread in the Klamath Basin and occur at or in close proximity to most ofthe sites occupied by Oregon spotted frogs. Some ofthe non-native species in the Klamath Basin include brook trout, brown trout, brown bullhead, fathead minnow, sunfish, largemouth bass, crappie, and bullfrogs. The Jack Creek and Parsnip Lakes sites represent the only Oregon spotted frog populations in the Klamath Basin that currently lack exotic aquatic predators.

D. Livestock Grazing

Range-wide Despite a pronounced interest in the question, data on the impacts ofgrazing on Oregon spotted frogs are sparse. Several factors are likely to contribute to whether grazing has negative and/or positive local impacts on the species and its habitat. These factors include, but are not limited to the intensity ofgrazing, the timing ofgrazing relative to vulnerable life stages ofOregon spotted frog, and habitat type and extent.

Grazing effects are likely to be complex and vary among sites and seasons. However, the tendency for multiple life stages ofOregon spotted frog to use shallow edge habitats among emergent vegetation, and for livestock to use similar areas for grazing and watering, suggest

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there is potential for negative impacts from grazing. Because ofthis potential to have Oregon spotted frog life stages and livestock concentrated in the same areas and habitats, particularly in low water conditions, there are likely to be risks to Oregon spotted frogs associated with heavy livestock use: direct trampling ofvulnerable life stages such as metamorphic and young juvenile frogs; reduced water quality (e.g., increased nitrogenous waste, and possible introduction ofpathogens or hormones); and reduced or altered vegetation cover (important to spotted frog life stages as refugia from predators). Cause and effect information is lacking for all ofthese factors (Cushman and Pearl 2007), and further research is warranted to determine the magnitude ofthese potential impacts.

Experimental work is warranted to better understand whether specific levels and timing of grazing can be used to maintain or improve habitat conditions for Oregon spotted frog in sites where vegetation succession is a concern (Watson et al. 2003, Cuslunan and Pearl 2007). Assessments ofthe potential negative grazing effects, and a closer examination of management that will minimize those effects while helping to maintain open habitat, will assist in the development ofgrazing prescriptions where Oregon spotted frog conservation is a priority (Cushman and Pearl 2007). An adaptive management approach to grazing offers the potential to maintain desired habitat conditions, by separating livestock grazing from vulnerable life stages ofOregon spotted frog (Cushman and Pearl 2007).

Studies have been conducted on the relationships between livestock grazing and the Oregon spotted frogs' close relative, the Columbia spotted frog (Rana luteiventris). It is important to recognize that the responses ofColwnbia spotted frog to grazing should not be extrapolated to Oregon spotted frog because the two species differ in demography, habitat use, and their capacity to move terrestrially (Licht 1975). Bull and Hayes (2000) did not detect differences in the number ofegg masses or ofrecently metamorphosed Columbia spotted frogs in grazed and ungrazed sites. In addition, a study by Adams et al. (2009) found that despite significant effects ofgrazing on vegetation height, there was no evidence that full or partial grazing exclosures affected Columbia spotted frog egg mass counts, larval survival, or metamorphic size in the first two or three years after fence installation.

Klamath Basin Grazing may pose a greater risk in the Klamath Basin than in other parts ofthe Oregon spotted frog range because the negative impacts may be more severe in low water years. Livestock grazing is occurring in most of the populations in the Klamath Basin, and the timing and intensity ofgrazing is variable. The specific impacts from grazing in the Klamath Basin are largely unknown and warrant further investigation into the potential impacts.

In 2005, a graduate student from Oregon State University completed her master's thesis on the impacts oflivestock grazing on habitat use by adult Oregon spotted frogs by monitoring frog locations in grazed and ungrazed treatments on Jack Creek (Shovlain 2005). Based on the proportion oftime frogs spent inside exclosures, there was evidence that as grazing pressure increased, frogs preferred ungrazed livestock exclosures. Although the frogs responded to grazing, this study could not detennine ifgrazing has either a positive or negative impact on the frogs (Shovlain 2005).

9 E. Water Quality Degradation

Range-wide Water quality and the absorption ofcontaminants in water through the skin and gills in immature forms may threaten this species (Marco et a1. 1999). Acidification ofwater, as reflected by low pH can inhibit fertilization and embryonic development in amphibians, reduce their growth and survival through physiological alterations, and produce developmental anomalies (Hayes and Jennings 1986, Boyer and Grue 1995). Research conducted by McKibbin et a1. (2008) suggests that water quality did correlate significantly with the embryonic survivorship ofOregon spotted frog population at two study sites in British Columbia, Canada.

A low pH may enhance the effects ofother factors, such as mobilization ofheavy metals from sediments. Pesticides, herbicides, heavy metals, nitrates and nitrites, and other contaminants introduced into the aquatic environment are known to negatively affect various life stages ofa wide range of amphibian species, including ranid frogs (Hayes and Jennings 1986, Boyer and Grue 1995). When nitrogen in the form of ammonia is introduced into water, the ammonia may "consume" dissolved oxygen as nitrifying bacteria convert the ammonia into nitrite and nitrate (DEQ 2002). Marco et al. (1999) found that Oregon spotted frog are very susceptible to chronic doses ofnitrate and nitrite.

Klamath Basin Water quality data at occupied Oregon spotted frog sites in the Klamath Basin are limited. Most ofthe available information discussed below applies to the entire Klamath Basin, including the Upper Klamath Basin in Oregon and the Lower Klamath Basin in California, and is not meant to imply that these conditions exist at known Oregon spotted frog locations. Additional investigation and monitoring ofwater quality and its effects on Klamath Basin Oregon spotted frog populations is warranted and important for conservation ofthis species.

Historical changes in land and water usage have impacted nutrient cycling dynamics in much ofthe Klamath Basin (DEQ 2002). In the Upper Klamath Lake and Agency Lakes, total phosphorus is identified as a pollutant that causes elevated pH, reductions in dissolved oxygen, and increases in chlorophyll-a, often pushing the lakes into an exaggerated state of eutrophication (DEQ 2002). Although historical accounts indicate that Upper Klamath Lake and Agency Lakes would have been considered eutrophic even 100 years ago, many locations have observed total phosphorous concentrations elevated significantly above these background levels contributed from agricultural and other nonpoint sources (DEQ 2002).

Waters at the Klamath Basin National Wildlife Refuges have high temperatures, elevated pH, and low dissolved oxygen (Sorenson and Schwarzbach 1991), which singly or in . combinations could have detrimental effect on the developing embryos offrogs (Boyer and Grue 1995). Water at the Klamath Basin National Wildlife Refuges contained ammonia (NH3) levels above those levels reported to have no-observed-effect concentration for leopard frog tadpoles (Boyer and Grue 2008). In addition, a study conducted in 1988-1989 detected five different organochlorine pesticides in bottom sediment (Sorenson and Schwarzbach 1991).

10 F. Isolation and Ownership

Range-wide For a highly aquatic species such as the Oregon spotted frog, which breeds in specific wetland types and exists in a landscape often substantially altered from historic conditions, factors relating to isolation include: 1) distance between sites; 2) permeability ofhabitat between source site and nearest breeding site; 3) frequency ofdispersal movements; and 4) risks to Oregon spotted frogs moving between potential breeding sites (e.g., exotic predators, culverts, etc.) (Cushman and Pearl 2007). With the exception ofthe upper Deschutes Basin sites, distances separating most ofthe known Oregon spotted frog populations are generally at least 2 kilometers (km) (1.2 miles (mi)) from one another (Cushman and Pearl 2007). Long distance movements by Oregon spotted frog appear to be infrequent and strongly linked to aquatic corridors (Watson et al. 2003).

A recent genetic analysis by Funk et al. (2008) found low levels ofwithin population genetic variation in Oregon spotted frogs. Low genetic variation may be attributed to small effective population sizes, historic or current genetic bottlenecks, and/or low levels ofwithin population genetic variation (Funk et al. 2008).

Klamath Basin The straight line distance between Oregon spotted frog populations range from 2.41 to 24.1 km (1.5 to IS miles) in the Klamath Basin. In the case ofJack Creek, the distance is very long (approximately IS miles) to its nearest known adjacent population (Williamson River, Klamath Marsh National Wildlife Refuge), and in many years it is connected with surface water for only very brief periods during snow melt.

More than 34% ofthe Klamath Basin is in private ownership (DEQ 2002), and it is suspected there are undiscovered Oregon spotted frog populations on private lands. Most ofthe known populations ofOregon spotted frog in the Klamath Basin are found in mixed ownerships including both federal and private lands. In some cases, this mixed ownership may provide challenges for conservation and restoration.

G. Climate Change

Range-wide Climate change is generally predicted to result in increased air and water temperatures, decreased water quality, increased evaporation rates, increased proportion ofprecipitation as rain instead of snow, earlier and shorter runoffseasons, and increased variability in precipitation patterns (Adams and Peck 2002). Winter snow pack accumulations are expected to be reduced due to wanner winter and spring temperatures, winter snowline will shift to higher elevations, and snow will melt earlier in the spring (Mote et al. 2003). Snow pack in the Washington Cascades is predicted to decrease by 44% by 2020 and by 58% by 2040 as compared to current conditions (Lawler and Mathias 2007). Less snow pack, especially at lower elevations, will likely result in lower summer water flow and increased summer water temperatures.

II Localized drought can negatively impact Oregon spotted frogs in all life cycles, particularly in isolated populations occupying fragmented habitat. Seasonal drought affects populations by increasing the likelihood ofegg mass desiccation and exposure to freezing; concentrating post-metamorphs, thus elevating predation risk; and increasing the impacts oflocalized events (Licht 1974, 1975; Kiesecker and Blaustein 1997). Multiple year droughts carry impacts similar to seasonal droughts, but may expose populations to negative long term impacts including decreased population numbers, potential losses in population heterozygosity, exacerbation ofimpacts from catastrophic events, and potential extirpation (which is more serious in isolated populations and metapopulations with remote chances of being recolonized).

Changes in water levels due to climate change or localized drought can cause seasonal loss of habitat and degradation ofessential shoreline vegetation. Hayes (1997) assessed 38 percent ofOregon spotted frog sites as having a moderate to high risk from drought (i.e. the potential for a drop in water level that could reduce or eliminate the species' habitat). Locations expected to have the greatest risk from drought are those dependent upon on surface flow rather than flows from springs. Sites with the greatest risk from drought are in Oregon in the Klamath and Deschutes Basins (Hayes 1997).

Klamath Basin Recent reports have examined climatologic and hydrologic information for Klamath Marsh and the Upper Klamath Basin. Mayer et a1. (2007) found that, similar to Klamath Marsh, inflows and tributary flows at Upper Klamath Lake show a long-term declining trend. The declines are particularly notable when examining the late summer/fall base flow period ofthe year. The results indicate that there has been a statistically significant decline in late season net inflows to the lake over the 1961 to 2007 period (Mayer 2008). Climate change is likely to affect sites differently in the Klamath Basin based on the water source. The effects of climate change are expected to be more evident in systems that are dependent on snow melt such as Jack Creek and less evident in systems that are dependent on ground water such as Crane Creek and Wood River.

In general, the water supply in the Klamath Basin is expected to become more variable. Dry years or periods with wide variation in the water supply have become more common. As a result, is it expected that the magnitude of stressors to Oregon spotted frog will increase as they interact with water supply. For example, stressors such as grazing, bullfrog and fish predation, and habitat loss to succession and plant invasions may become more acute risks in dry years. In recent years, low water conditions have resulted in the desiccation ofegg masses and stranding oftadpoles at Jack Creek.

H. Diseases

Range-wide Disease can strongly impact small populations that are already stressed by other factors (e.g. drought or low food availability). Amphibians are known to be affected by a variety of diseases (Berger et a1. 1998). There is little information on the specific effects ofdisease and parasitism on Oregon spotted frogs. Oomycete fungi (including Saprolegnia sp; Petrisko et

12 al. 2008) and the chytrid fungus (Batrachochytrium dendrobatatidis; Pearl et al. 2009) have been found on Oregon spotted frog life stages, but their effects at the population scale are poorly known. BatrachochytriunI dendrobatatidis in particular, merits further attention, since it has impacted amphibian populations in other regions ofthe world.

Klamath Basin A study conducted by Pearl et al. (2009), detected BatrachochytriunI dendrobatatidis (Bd) in all ofthe 36 Oregon spotted frog sites sampled, including five sites located in the Klamath Basin. This study detected one ofthe highest rates ofBd prevalence (68.1 % ofjuveniles and adults) and occupancy (100% of surveyed sites), but found low prevalence ofBd in larvae (2.8%) (Pearl et al. 2009). The paucity ofdata on ccological effects ofchytrid fungus makes it impossible to assess the threat it may present to Klamath populations.

VIII. CONSERVATION ACTIONS TO BE UNDERTAKEN

The Fremont-Winema National Forests, Lakeview District ofthe Bureau ofLand Management, Medford District of the Bureau of Land Management, and Klamath Marsh National Wildlife Refuge agree to work locally and cooperatively to:

I) Develop Oregon Spotted Frog Site Management Plans for each spotted frog population on federal lands within the Klamath Basin. The Plans may include recommendations ofsite specific management actions, and the desired timeline for each conservation action. By 2012, each site will have a plan completed. 2) By 2011, identify and prioritize research needs for the conservation ofthe species in the Klamath Basin. This includes estimating the funding and personnel needs to carry out such research needs. 3) By 2011, evaluate connectivity concerns between sites in the Klamath Basin. Identify feasible improvements for connectivity between sites, determine appropriate management actions through restoration, and include these actions along with funding requests in Site Management Plans. 4) Where feasible, work to restore or enhance ephemeral and permanent wetlands within and adjacent to occupied Oregon spotted frog sites. Identify these ephemeral and permanent wetlands, determine the appropriate management needed for restoration, and include these actions along with funding requests in Site Management Plans. 5) Work to restore and maintain open water in occupied Oregon spotted frog habitat and provide early seral vegetation communities in close proximity to occupied Oregon spotted frog habitat sites. Identify areas that lack open water conditions, determine appropriate management actions, and include these actions along with funding requests in Site Management Plans. 6) Where grazing on Federal lands occurs in occupied Oregon spotted frog habitat, then develop a comprehensive grazing strategy using adaptive management principles through a collaborative process. This process should include interdisciplinary discussion and reviews from federal wildlife biologists, range conservationists, and other specialists as needed, as well as the perspectives ofthe permittee and/or private landowner, and the USFWS. The final decision as to which strategy to adopt remains with the appropriate federal line officer.

13 7) Evaluate whether local fish stocking practices may be adversely affecting Oregon spotted frog populations and propose adjustments ifneeded. Site Management Plans will assess whether non-native fish are present at the Oregon spotted frog sites, what the potential negative effect oftheir presence may be, and propose adjustments ifneeded. 8) Develop cooperative Oregon spotted frog restoration projects with our partners and pursue outside funding for project implementation. Cooperatively work with our partners on developing grant proposals to leverage funding. 9) Coordinate and prioritize surveys an on annual basis to monitor Oregon spotted frog populations and describe habitat conditions. Participate in range-wide monitoring strategies. Pursue funding for monitoring of Oregon spotted frog restoration projects. 10) On an annual basis, provide all existing Oregon spotted frog survey and habitat data to the USFWS to enter into a universal data base. II) Continue to participate in the Regional Interagency Special Status Species (ISSSP) Oregon Spotted Frog Working Group to identify priorities and information needs. 12) On an annual basis, enter all data into NRlS Wildlife, GeoBOB, or ORNHIC. 13) In cooperation with the USFWS, work collaboratively with private landowners to manage, restore, and monitor populations on private lands located near or adjacent to federal lands and that have known or suspected Oregon spotted frog habitat. 14) Increase awareness ofOregon Spotted frog management and conservation needs through public outreach and education. IS) In support ofadaptive management, a review ofthis conservation agreement and each individual Site Management Plan will be conducted every five years to update with new scientific findings or habitat infonnation.

The Klamath Falls Fish and Wildlife Office of the U.S. Fish and Wildlife Service agrees to work locally and cooperatively to:

I. Assist the Forest, Districts, and Refuge in managing Oregon spotted frog populations and habitats within the Klamath Basin, and to protect their significant biological and ecological values consistent with current law, regulations, policies, and existing management plans. 2. Review monitoring data and conservation activities in cooperation with the Forest, Districts, and Refuge and recommend changes in the status ofthe Oregon spotted frog as appropriate. 3. Meet annually or as needed with Forest, Districts, and Refuge to discuss Oregon spotted frog status and management needs. 4. Share all new information on the Oregon spotted frog with the Forest, Districts, and Refuge. 5. Assist with the development and review ofSite Management Plans. 6. Continue to participate in the Regional Interagency Special Status Species (ISSSP) Oregon Spotted Frog Working Group to identify priorities and information needs. 7. Support implementation and monitoring ofactions that conserve and protect the species by providing funding ifpossible, helping to search out potential funding sources, and assisting with grant writing as appropriate. 8. By 2012, develop an Interagency Klamath Basin Oregon Spotted Frog Action Plan and prioritize potential restoration projects across the various spotted frog populations in the basin. This plan will be updated annually as new Site Management Plans are created, new information is gathered, and new restoration actions are proposed.

14 9. Work collaboratively with private landowners to manage, restore, and monitor populations on adjacent private lands which have known or suspected Oregon spotted frog habitat. 10. Provide financial and technical support for monitoring, research, and education efforts where feasible. 11. Compile all existing Oregon spotted frog survey and habitat data into a universal database. 12. Increase awareness ofOregon Spotted frog management and conservation needs through public outreach and education. 13. In support of adaptive management, a review ofthis conservation agreement and each individual site management plan will be conducted every five years to update with new scientific findings or habitat infonnation.

IX. FUNDING AND IMPLEMENTATION OF CONSERVATION MEASURES

This Conservation Agreement is subject to available funding and staffing. This does not impose financial obligations on any ofthe federal agencies signing this agreement. The parties to this agreement are committed to seeking funding to implement this conservation agreement each year.

X. DURATION OF AGREEMENT

The duration ofthis Conservation Agreement is for 10 years following the date ofthe last signature. The parties involved will review the Conservation Agreement and its effectiveness every 5 years to detennine whether it should be revised. During the last month in which it is valid, the Conservation Agreement must be reviewed and either modified, renewed, or tenninated. Ifsome portion ofthis Agreement cannot be carried out or ifcancellation is desired, the party requesting such action will noti fy the other parties within one month ofthe changed circumstances.

15 XI. SIGNATURES

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J. Rich I' (Rick) Newton, Acting Forest Supervisor Dute Fremont-Winema National Forests US. Forest Service

Carol BelJkosky, District Mana er Date Lakeview District Bureau ofLand Management

Tim Reuwsaat, District Manager Medford District Bureau ofLand Management

Ron Cole, Project Leader Date Klamath Basin National Wildlife Refuges US. Fish and Wildlife Service

16 VI. BIBLIOGRAPHY AND PERSONAL COMMUNICATION

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20 "

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