Food Chain Restoration for Pollinators: Regional Habitat Recovery Strategies Involving Protected Areas of the Southwest Author(s): Steve Buckley and Gary Paul Nabhan Source: Natural Areas Journal, 36(4):489-497. Published By: Natural Areas Association DOI: http://dx.doi.org/10.3375/043.036.0415 URL: http://www.bioone.org/doi/full/10.3375/043.036.0415
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BioOne sees sustainable scholarly publishing as an inherently collaborative enterprise connecting authors, nonprofit publishers, academic institutions, research libraries, and research funders in the common goal of maximizing access to critical research. ABSTRACT: The steep declines over the last quarter century of wild pollinators in the Southwest among • native bees, monarch butterflies (Danaus plexippus L.), hummingbirds, and nectar-feeding bats have come during a time of accelerated climate change, and are likely due to a variety of stresses interacting with climatic shifts. Nevertheless, there is mounting evidence that declining availability and altered timing of floral resources along “nectar corridors” accessible to pollinators involves climatic shifts as a serious stressor that had been previously underestimated. Longitudinal studies from both urban heat islands Food Chain and rural habitats in Southwestern North America suggest peak flowering of many wildflowers serving as floral resources for pollinators is occurring three to five weeks earlier in spring than a century ago, leaving “phenological gaps” in nectar resource availability for certain pollinators. To avoid the threat of Restoration for what A. Dobson (Professor of Ecology and Evolutionary Biology, Princeton University) and others have termed “food web collapse,” a range of groups have initiated ecological restoration efforts in semi-arid Pollinators: Regional zones that attempt to (a) assemble more resilient plant–pollinator food chains, and (b) hydrologically restore watercourses to ensure water scarcity will be less likely to disrupt re-assembled food chains in the face of droughts, catastrophic floods, and other correlates of global climate change. We recom- Habitat Recovery mend “bottom-up food chain restoration” strategies for restoring nectar corridors in protected areas on or near geopolitical and land management boundaries in all regions, but particularly in the Southwest Strategies Involving or US-Mexico desert border states. We highlight binational and multicultural workshops facilitated to communicate about, and initiate restoration of, mutualistic relationships among plants, pollinators, and Protected Areas of people to protected area managers on both sides of the border. the Southwest Index terms: climate change, food web restoration, phenological mismatch, pollinators
INTRODUCTION plant–pollinator systems. Perhaps nowhere else in North America are these disruptions There is now widespread scientific agree- already so evident as in the Southwest or Steve Buckley1,3 ment that dramatic declines and changes US-Mexico border states, where complex in the ranges of both migratory and topography, habitat heterogeneity, and high center-foraging wild pollinators of many plant diversity all contribute to a richer 1 National Park Service kinds have occurred over the last quarter suite of pollinators than is found in other Southwest Exotic Plant Management century (Buchmann and Nabhan 1996; regions of comparable size in North Amer- Team Allen-Wardell et al. 1998; Goulson et al. ica (Nabhan 2013). Already, the changes 12661 E. Broadway Blvd. 2015). What is less clear is the extent to in the climate system in this region over Tucson, AZ 85748 which these precipitous declines have been the last 20 to 30 years are resulting in phe- primarily driven by, or secondarily accel- nological shifts that could have significant erated by, climate change over the same implications for wild pollinators and their Gary Paul Nabhan2 time period (Inouye 2009; Abrol 2012; food webs (Bowers 2007; Crimmins et al. Martin 2015). Nevertheless, one survey of 2010; Fabina et al. 2010). 2University of Arizona 1420 species of pollinators known to visit Center for Regional Food Studies at least 429 kinds of plants predicts that For those engaged in conservation biology Tucson, AZ 85748 climate-driven changes in flowering times and protected areas management, we must will reduce available floral resources for consider whether we have inadvertently at least 17% and perhaps as many as 50% narrowed public concern too much by of all pollinators, resulting in diminished advancing conservation largely through • nutritional diversity within their diets attempts to simply avert extinction and (Memmot et al. 2007). While specific foster recovery of single imperiled species. predictions for climate change impacts Today, we have the opportunity and need 3 Corresponding author: steve_buckley@ are difficult to discern, there is concern to build broader public support for the nps.gov; 530-595-6187 for the fate of pollinators worldwide and more complex task of managing lands for the potentially catastrophic implications the “conservation of mutualisms” (Nabhan for human well-being. and Fleming 2002) and “restoration of food webs” (Dobson et al. 2009). It may well be Abrol (2012) asserts that the current “pol- that Vitousek et al. (1997) are correct that lination crisis” may be due to climatic climate change and other environmental changes aggravating “disruption of the crit- disruptions are unraveling the “tangled Natural Areas Journal 36:489–497 ical balance between the two mutually-in- bank” of complex ecological networks first teracting organisms” in several co-evolved described by Darwin from an evolutionary
Volume 36 (4), 2016 Natural Areas Journal 489 perspective. If so, it behooves us to try to and pollinator health (Bowers 2007; Mill- the Sonoran Desert in Arizona across the manage whichever variables we can before er-Rushing and Primack 2008; Crimmins last century illustrate the trend in earlier ecological networks become simplified et al. 2010; Elwood et al. 2013). Pollinator flowering of herbaceous perennials such through the disruption of interspecific in- specialists (such as oligolectic bees) and as Hibiscus denudatus Benth. (Figure 1). teractions in space and time and contribute even generalists (such as polylectic bees) to food chain collapse. have the potential to suffer phenological This shift of flowering by more than 30 disruption, with fitness consequences both days is representative of broader trends We propose here that ecological restoration nutritionally or reproductively, because of documented by Bowers (2007) for the efforts in and beyond protected areas must temporal and spatial shifts in flowering majority of 100 Sonoran Desert species focus more on “food chain restoration,” not times (Waser et al. 1996; Tepedino et al. examined more broadly in Pima County, only for plants and their pollinators, but 2014; Rafferty et al. 2015). The implication Arizona, over roughly the same time more broadly for entire food webs that offer is that reduced floral richness of nectar period. There was a 20 to 41 day earlier us natural capital and ecosystem services plants during the foraging and breeding flowering from 1894 to 2004, with the as crop pollinators surely do. Restoring season of certain pollinators could affect decline of floral resources in late winter food webs includes enhancing soil mois- the nutritional status and limit the fitness or and early spring, just as many native bees ture through the restoration of hydrologic reproductive success of those pollinators, and butterflies emerge, and migratory function using constructed water harvesting which will likely have disproportionate bats, hummingbirds, and mourning doves features, which in turn support restoration consequences for specialists (Memmott et (Zenaida macroura L.) are returning to the of native plant communities along with al. 2007; Hegland et al. 2009). Sonoran Desert uplands. native soil fauna. These links in the food chain then support herbivores that feed Nevertheless, other studies (Memmott et Although earlier flowering by three to five predators, parasites, and pollinators. al. 2007; Fabina et al. 2010; Forrest and weeks does not categorically determine Thompson 2011; Inouye 2011) offer dif- phenological mismatches with either Food chain restoration includes conserving fering perspectives on how much climate migratory or year-round residential polli- existing native landscapes, along with change is already triggering “phenological nators, it is significant enough to warrant actively replanting a wide range of native mismatches” between flowers and pollina- further monitoring and management con- plant species in cultural or cultivated land- tors and how much of an impact such mis- siderations. When coupled with extensive scapes (Menz et al. 2011; Wratten et al. matches will have. Such mismatches occur land use conversion and habitat fragmen- 2012). These efforts may restore critically when species that depend on one another tation associated with human development, important nectar resources at migratory become so separated in time or space that along with the spread of nonnative species, stopovers and extend nectar bridges to they can no longer interact. Hypothetically, the nectar landscapes supporting these shape long-distance corridors (Nabhan such mismatches may generate cascading plant–pollinator interactions appear to 2004). This, in fact, is the proposed strategy effects that ripple throughout a biotic become increasingly fragile. for tri-national monarch butterfly Danaus( community or landscape. In particular, plexippus L.) conservation efforts, which ecological models of food webs developed And yet, until recently, the possible need for include planting both milkweeds for larval by Fabina et al. (2010) now suggest that food web restoration in once-diverse wild food as well as a wide range of nectar plants climate change-induced phenological shifts landscapes has largely been overlooked in that are essential for migration (Nabhan et can have a major impact on communities principles and practice of restoration ecol- al. 2015). We will also briefly comment even in cases where complete phenological ogy (Vander Zanden et al. 2006; Clewell on what such a paradigm shift implies for mismatches do not occur. This may be be- and Aronson 2007; Mader et al. 2011; transboundary conservation management cause the mismatching of flowering times Menz et al. 2011). Research supporting of migratory corridors (Lopez-Hoffman with the timing of pollinator emergence restoration of pollinator communities in et al. 2009), and for our efforts to train or arrival may be only one of many ways natural habitats has received much less em- protected area managers on both sides of that plant–pollinator interactions may be phasis than in agricultural settings (Menz the US-Mexico border in pragmatic food disrupted by climate change (Table 1). et al. 2011), although there are examples chain restoration techniques. Rafferty et al. (2015) are more direct, from around the world for restoration noting that they “expect non-symbiotic of plant–pollinator networks (Forup and Pitfalls of Disrupted Plant–Pollinator mutualisms to be more susceptible to Memmott 2005; Winfree 2010; Devoto et Interactions phenological disruption.” al. 2012; Pocock et al. 2012). A search of the ISI Web of Science database for the Numerous field studies in North America— There are numerous studies documenting search terms mutualis* and restor* reveals but particularly in the Southwest—have phenological changes in vascular plants 418 papers, but when the search query is confirmed climate change as the likely linked to climate change (Primack et al. refined further to include the search term driver of significant temporal and spatial 2004; Miller-Rushing and Inouye 2009; Ariz*, not a single result was returned. shifts in flowering times for nectar re- Davis et al. 2015; Munson and Sher 2015). The term Mexico* added to the search sources critically important to pollination Herbarium collections data drawn from terms yielded only two papers. While
490 Natural Areas Journal Volume 36 (4), 2016 Table 1. Examples of disruptions to plant–pollinator and plant–herbivore interactions.
Interaction Case study Potential impacts Consequences Reference Pollinator larva Monarchs (Danaus Killing of milkweeds Dramatic declines in Pleasants and feeding on specific plexippus ) on by glyphosate monarch reach, Oberhauser 2012 host plant milkweeds (Asclepias herbicides reproduction & spp.) migratory success Sequential mutualism Bear poppy Changing competitive Decline of specialized Tepedino et al. 2014 of floral species to (Arctomecon humilis ) advantages of pollinators provide nectar and and other flowers in polylectic and pollen to pollinator sequence with Perdita oligolectic bees; bee meconis and polylects parasites & local land use disruptions Flowering time Asynchronies between Climate change; urban Lowered plant Memmot et al 2007; amplitude in relation pollinating insects and heat island effect; survival, reduced Inouye 2009, 2011; to pollinator activity various flowering parasites and fertilization through Fabina et al. 2010; shrubs & annuals pesticides pollination & lowered Forrest and Thompson seed set; diminished 2011; Goulson 2015 nutritional value of foraging the literature describing mutualisms and across disciplines to develop a coordinated landscapes and facilitating species recovery plant–pollinator interactions in this region approach to “bottom up” restoration of must begin with hydrological restoration is substantial, there are surprisingly few pollinator food chains in one of the most of critical breeding and migratory stop- papers that broadly address the restoration diverse landscapes in the United States for over habitats where plant cover has been of pollinator food chains in the Southwest native pollinators (Minckley and Ascher degraded or denuded over time. The San in terms of management. 2013; Nabhan 2013). It is a landscape Bernardino Valley in southern Arizona is where flowering times and longevity for one of these areas, where ongoing conser- The following examples offer applications many plants appear to be shifting due to vation efforts provide us with a glimpse of of the concept of food chain restoration water deficits triggered by climate change, how the restoration of both hydrological for pollinators in both wild and developed aquifer depletion, and drought. Researchers and ecological processes contributes to landscapes within and adjacent to protect- have hypothesized that supporting nectar pollinator recovery and persistence. ed areas in the US-Mexico borderlands. These applications include how collabo- rative efforts can connect the threads of research, restoration, and adaptation into localized community based solutions, further tying protected areas to their sur- rounding communities, both human and more-than-human.
APPLICATIONS OF THE MANAGEMENT OF PROTECTED AREAS IN THE US-MEXICO BORDERLANDS
Bees and Migratory Pollinators in San Bernardino Valley, Arizona-Sonora
In southern Arizona along the US-Mex- Figure 1. Flowering times of herbarium specimens of Hibiscus denudatus collected over a century’s time ico border, conservation biologists and in the Sonoran Desert in Arizona illustrate the trend of earlier flowering time. resource managers are working together
Volume 36 (4), 2016 Natural Areas Journal 491 Capitalizing on research to assess wa- The next step involves nonprofits like Sky notice nest failure among hummingbirds ter harvesting through the use of both Island Alliance (SIA) and Borderlands during the hottest and driest time of the small rock structures known locally as Restoration Habitat Network (BHN) to year on her own properties along Harshaw “trincheras” and larger structures known direct and guide volunteers to install the Creek. Southeastern Arizona is known to as gabions, researchers are illustrating that plants and reseed areas after hydrological have 15 regularly occurring species of bringing back water in desert landscapes restoration. Direct seeding has added hummingbirds, and many of these are can increase the availability of water and dozens of species important to pollinator migratory (Wethington et al. 2005). At the eventually increase the richness of plant communities in the last couple years. These same time, her husband, Lee Rogers, ob- species associated with these riparian include numerous species of Asteraceae served poor fruit set in their tree plantings habitats (Norman et al. 2014). At the San that have substantial importance in helping in their two acre Tsintsuntsani Orchard on Bernardino National Wildlife Refuge, and monarch butterflies build the necessary the same property; both noticed a lack of on adjacent ranch land in Mexico, various lipid reserves for their journey south, and flowers outside fo the cultivated fruit trees US agencies (United States Geological Sur- Asclepias, or milkweed, to support larval during early to mid-spring. Phenological vey (USGS), Bureau of Land Management food resources for when they return. These monitoring through a USDA-WSARE (BLM), and Fish and Wildlife Service) are seed mixes include local species of Salvia (US Department of Agriculture-Western working cooperatively at the watershed and Penstemon to support migratory hum- Sustainable Agriculture Research and Edu- scale with the nonprofit, Cuenca Los Ojos mingbird habitat, and species of Agave to cation Program) grant to the University of Foundation (CLO), to restore large sections support many different pollinator species, Arizona Southwest Center and to Border- of the headwaters of the Rio Yaqui in the but especially bats. We are learning that lands Restoration confirmed phenological San Bernardino Valley. conserving migratory pathways for species gaps in flower availability that potentially like monarch butterflies, hummingbirds, affected both migratory hummingbirds The San Bernardino Valley has the highest and lesser long-nosed bats (Leptonycteris and native ground-nesting bees in their bee diversity in the region and perhaps the yerbabuenae ssp. curasoae Martinez and Tsintsuntsani Orchard (Figure 2A). nation, supporting more than 435 known Villa) means coming to some understand- species of bees, and serves as a critical ing about our own essential mutualism and These observations were suggestive of a linkage to nectar corridors between the dependence upon them for the long-term changing nectar landscape that might be United States and northwestern Mexico survival of both the pollinator and human having profound consequences for the (Minckley and Ascher 2013). Land man- communities (Kearns et al. 1998). breeding and nesting of hummingbirds, agers in these areas have begun a multiyear along with the availability of bee pollina- process with the end goal of restoring a Ongoing monitoring by USGS aims to tors for fruit tree pollination. In response range of beneficial pollinator plant species characterize and quantify the recovery of to these data, Borderlands Restoration and through both seeding and direct outplanting vegetation at restoration sites and examine the University of Arizona WSARE project to support and enhance bee populations at the long-term persistence of these efforts. helped Wethington and Rogers, as well as sites throughout the region. The work hinges on public–private collabo- managers of six other on-farm restoration rations that involve researchers, citizen sci- sites nearby, to identify “pollinator-attract- This interagency collaboration includes entists, growers, agencies, and community ing perennials” that helped bridge these systematic seed collection efforts, first groups working together to build the critical phenological gaps in order to maintain through the identification of those plant restoration infrastructure that will sustain the supply of nectar and pollen for birds, species that support pollinator communi- long-term local efforts. Restoration work bees, and other pollinators (Figure 2B ). ties, then with collection of both framework on CLO lands in Sonora, Mexico, has been (critically important nectar species) and ongoing for 30 years and further illustrates In addition to managing the new bridge species (resource rich species with the possibility of restoring functioning river WSARE-supported hedgerow plantings broad application for restoration) (Dixon systems in semi-arid zones. on the orchard’s edge, Wethington and 2009). Seed collection ranges widely across Rogers have worked with Borderlands the region to capture the genetic diversity Hummingbirds in Harshaw Creek, Restoration to install water-harvesting of important species, in cooperation with Patagonia, Arizona structures throughout their property that hy- national programs like the BLM’s Seeds of drologically support additional outplanting Success (SOS). These collections are also In similar fashion, several properties man- of thousands more native plants. The hope sent to local and regional plant material aged for wildlife conservation near Pata- is that these plants will fill nectar gaps and production facilities, like the Madrean gonia, Arizona, provide a lesson on how provide nectar throughout the year for hum- Archipelago Plant Propagation (MAPP) to restore food chains to support migratory mingbirds. Continued monitoring of the Center, where local community groups hummingbirds, and possibly, native bees restoration sites has illustrated many of the and agencies are collaborating to grow out and bats. In association with participants pitfalls associated with restoration projects, important species for both direct planting in the international nonprofit Hummingbird including poor survival of outplantings in in the protected areas and to be grown for Monitoring Network that she co-founded, years marked by highly variable rainfall. regionally adapted seed stock. avian ecologist Susan Wethington began to Even with short-term setbacks, these efforts
492 Natural Areas Journal Volume 36 (4), 2016 techniques and have constructed water harvesting structures and planted plants at the site, along with installing bee boxes at the site, to improve the availability of bee habitat for nesting and reproduction. All these efforts are still being closely monitored by the Hummingbird Moni- toring Network and by citizen scientists at Borderlands Restoration. Early results indicate that while gaps do remain in the nectar landscape, it is well worth the effort to gradually “fill in” those gaps to support the 15 species of hummingbirds known to the region (Wethington et al. 2010). The next steps are to persist in these efforts and continue to add nectar resources to the landscape over coming years.
Lesser Long-nosed Bats at Coronado National Memorial
Thirty miles east of Patagonia in Corona- do National Memorial along the Arizona/ Sonora, Mexico, border, park managers guided by Arizona-Sonora Desert Museum biologists are restoring habitat for lesser long-nosed bat populations. They seek to sustain the “nectar corridors” required by this endangered species by growing and restoring the lechuguilla agave (Agave palmeri Engelm.) on National Park Service lands to serve as critical food resources along known bat flyways that straddle the US-Mexico border (Nabhan and Fleming 2002; Ober and Steidl 2004).
Using mitigation money from the De- partment of Homeland Security to offset losses of agave due to the construction of the border fence, managers are building local capacity to grow large quantities of agaves indefinitely, working with both Figure 2. A (top): Pre-treatment phenology of the Tsintsuntsani Orchard in Patagonia, Arizona, illus- local and regional nurseries to increase the trating the phenological gaps in the nectar landscape. B (bottom): Restoration efforts were made using available supply. The challenge presented 20 different pollinator-attracting perennials from the families Asteraceae, Fabaceae, Grossulariaceae, by long-lived species like agave is building Lamiaceae, Onagraceae, Plantaginaceae, Rosaceae, and Verbenaceae that helped bridge the phenological gaps in the nectar landscape.The Figure 2B legend is included to provide species detail more than species a genetically appropriate and readily avail- phenology (difficult to distinguish in greyscale). (Source: G. Nabhan and C. Weaver) able supply for regional restoration efforts, which means growing plants three or more years before planting. This necessitates a have developed sufficient local capacity for These efforts attracted the attention of commitment on the part of managers for doing further restoration. Increases in base the US Forest Service (USFS) who, in long-term engagement with local commu- flow observed in Harshaw Creek—anec- cooperation with the USGS, have installed nities and nurseries to support growing the dotally attributed to the water harvesting stream gauges downstream to quantify the hundreds of thousands of plants that are structures—mean additional planting and impacts of the low-tech rock structures on needed. In the case of Coronado National seeding efforts can continue to fill the gaps water quantity, quality, and persistence. Memorial, it also includes the involvement in the nectar landscape for years to come. Local youth are being trained in restoration of local elementary school students in the
Volume 36 (4), 2016 Natural Areas Journal 493 entire cycle of restoration, from learning migratory and transboundary pollinator tected areas and the wildlands they inhabit. about the lesser long-nosed bat through populations. In Southwestern ecosystems, many exotic classroom lessons, to harvesting seed and plants are wind-pollinated (i.e., buffelgrass growing plants, to eventually visiting the Beginning in 2014, the SWEPMT began (Pennisetum ciliare L.), cheatgrass (Bromus park and planting out the next generation systematically restoring exotic plant tectorum L.)), and while some flowering of plants. infested areas in the parks to increase exotic plants might have limited benefits native habitat for flowering plants that to generalist pollinators by providing addi- The agaves used in these outplantings are directly supports pollinator recovery and tional floral resources, the decline of native propagated from seed collected at the park other ecological services and values. These biodiversity and flowering plants has subtle, and from sites nearby in the Madrean Ar- efforts include systematically identifying and potentially more, far-reaching negative chipelago region. Park managers are now both framework and bridge species of impacts on pollinator health (Aizen et al. working on plans to plant at multiple park importance, collecting seed and increasing 2008; Potts et al. 2010; Burghardt and units and at hundreds of other sites through- the available seed supply of critical polli- Tallamy 2015). out the region. The intention is to create a nator-supporting species, and developing network of agave pollinator habitat that can collaborations with researchers to inventory Restoration of these exotic plant infested offset losses from landscape fragmentation and monitor efforts to learn about what areas offers a unique window of opportuni- and development, overharvesting for mes- works, which improves the SWEPMT’s ty to turn protected areas into focal points cal production, and changes in flowering ability to adaptively manage additional res- for food web restoration for pollinators. resources that are available to migratory toration efforts in line with other national Actively tending disturbed areas near the pollinators due to climate change (Nabhan efforts (Zavaleta et al. 2001; DOI 2015). core of visitation also takes advantage of 2004). This network of habitat is expanded the unique interpretive skills of the NPS to as more agaves are grown and included as In this centennial year of the NPS, the communicate to the public the necessity of a commonly available species for planting restoration of food chains for pollinator food web restoration for pollinators. From adjacent to hydrological restoration efforts. recovery is a natural fit for celebrating a land management perspective, using park the parks and their legacy of protecting infrastructure as a focal point addresses Building long-term restoration capacity valuable ecological places and processes in what is often a core problem in exotic puts people to work in local communities alignment with NPS policies on ecological plant management in terms of vectors for growing the plant material that takes years restoration (NPS 2006). Already in six na- both new introductions and for managing to fully mature before being put back into tional park units in southeastern Arizona, the vegetation in disturbed public areas the wild. Being able to integrate restoration large pollinator gardens are being designed (Welch et al. 2014). Concerted restoration efforts from the restoration of hydrological and implemented by managers to serve operations to deal with exotic plants and systems in protected areas along the bor- specific park goals for both vegetation and restore the nectar landscape in these high der, to the development of a wide range pollinator restoration and to contribute to traffic zones can have immediate and mul- of locally supplied and adapted pollinator the broader goals identified in the national tiple benefits for supporting the pollinator plant material, helps stitch the land back pollinator memorandum released by the food chain (Wratten et al. 2012; Morandin together to support pollinators and people. Obama administration (Obama 2014). This and Kremen 2013; Dicks et al. 2015). stepping stone corridor approach has been FOOD CHAIN RESTORATION identified as a first step for restoration pro- To accomplish larger scale restoration STRATEGIES FOR PROTECTED AREA grams connecting pollinator networks and efforts, here are several strategies being LANDSCAPES IN THE SOUTHWEST diverse pollinator communities (Menz et al. considered or implemented: 2011). Seed collection to support additional Managers in the US National Park Service gardens has been initiated in four states and (1) designing and building pollinator gar- (NPS) are scaling up from these localized at over a dozen parks. Pollinator inventory dens, or way-stations, augmenting existing examples in borderland areas to attempt a efforts have been initiated at several parks, flowering plants in all parks and protected coordinated regional approach to restoring including Tumacácori National Historical areas along major known nectar corridors habitats along pollinator corridors. As one Park, where a pollinator bioblitz connected (the I-35 milkweed corridor effort, which example, the Southwest Exotic Plant Man- local advocacy groups with taxa experts follows this north–south interstate running agement Team (SWEPMT) coordinates to establish baseline monitoring data for through the Midwest, is one such exam- restoration of exotic plant-invaded areas restoration efforts there using iNaturalist to ple, as are the nascent efforts to connect in 55 national park units spread across six connect with other citizen science efforts. hummingbird and bat flyways and parks Western states. The SWEPMT cooperates across the Southwest). with a wide range of land management Since many protected areas are becoming agencies, and nonprofit, limited profit, island-like sanctuaries of native vegeta- (2) working with researchers to develop and private groups to restore native bio- tion in the sea of anthropogenic change and to make available the best bilingual diversity and the nectar landscape in ways surrounding them, these integrated efforts information for park and protected area that support monarch butterflies and other focus on the point of contact between pro- managers about incorporating nectar plants
494 Natural Areas Journal Volume 36 (4), 2016 into resource management decisions, to National Phenology Network, through linator food chains and nectar landscapes provide publications and interpretive ma- iNaturalist, and through Naturalista, the all across the continent. terial for diverse audiences, and to conduct Spanish language platform of iNaturalist. monitoring that will feed critical infor- ACKNOWLEDGMENTS mation back to protected area managers Training workshops have occurred in the to adaptively manage restoration efforts Monte Mojonos Biosphere Reserve near The authors wish to acknowledge funding Alamos, Sonora, Big Bend National Park, from the National Park Service internation- (3) developing wide ranging partnerships the Coronado National Forest, and at the al program and Big Bend National Park, and collaborations to integrate efforts into Natural Resources Conservation Service’s regional, national, and international efforts the National Fish and Wildlife Foundation, Los Lunas Plant Materials Center in New and the W.K. Kellogg Foundation. Thanks Mexico. Such trainings are now being (4) expanding the capacity to grow and in- to Lori Makarick and Greg Eckert of the crease availability of a wide range of locally extended to indigenous areas of binational National Park Service and two anony- adapted and sourced pollinator plants in the borderlands, with certificate courses and mous reviewers for their helpful reviews, form of both seed and as nursery material, workshops planned for communities where comments, and insights. We thank Caleb in ways that provide unique restorative eco- Seri, Yaqui, Mayo, O’odham, and Kicka- Weaver and Ron Pulliam for the assistance nomic opportunities while simultaneously poo families live along nectar corridors and use of their data concerning WSARE supporting pollinator health. for migratory pollinators. In the United funded efforts examining nectar resources States, horticulturalists are working with in southeastern Arizona. We thank Susan the Intertribal Nursery Council and learning Wethington and Lee Rogers of the Hum- Expanding Binational and Cross- mingbird Monitoring Network, as well as cultural Training from successful tribal nurseries all across the western United States. The hope is to Laura Lopez-Hoffman, Steve Buchmann, One implication of our work with migratory develop a coordinated response through and Ina Warren, and the numerous people pollinators is that conservation actions need open information sharing and by providing who grow the plants, curate the seeds, to focus on weak links across entire “nectar training opportunities that link us all into and work tirelessly to grow a restoration economy in the southwestern United States. corridors,” not just in protected areas that an inclusive community of practice. may offer “stepping stone” refuges for stopover along the way. Because careful CONCLUSIONS Steve Buckley is the botanist for the South- management of a single site along a mi- west Exotic Plant Management Team of gratory corridor is obviously insufficient to Prior to 2015, the conservation of polli- the National Park Service. He works with sustain the entire migratory phenomenon, nators in or between protected areas had parks throughout the southwestern United regional efforts have emphasized cross-cul- focused more on the population biology of States to support restoration operations, tural training to achieve more harmonious individual species, rather than on managing seed collection, and plant materials devel- land uses, restored habitats, and compara- ecological interactions or “keystone rela- opment to support plant–pollinator inter- ble monitoring among protected areas on both sides of the U.S.-Mexico border. This tionships” (see Nabhan and Fleming 2002). actions and invasive species management. includes working with agencies, agricul- We believe there is an emerging paradigm Working with the BLM and other land tural interests, NGOs, and communities on shift toward restoration of ecological management agencies, he oversees the both sides of the border. interactions, away from single species Madrean Archipelago Plant Propagation approaches and toward the restoration of (MAPP) Center in Patagonia, Arizona, and In 2015 alone, the authors organized, mutualisms that occur along binational is finishing a doctorate at the University of facilitated, or instructed protected area “nectar corridors.” Collectively, we need Arizona on regional restoration strategies managers from Arizona, New Mexico, not limit this to mutualistic interactions for pollinators. Texas, Sonora, Chihuahua, Coahuila, among plants and pollinators alone, but Nuevo Leon, Tamaulipas, Queretaro, and by necessity should include people and Gary Paul Nabhan is the Director of the Guanajuato in milkweed seed collection, pollinators, and people and landscapes as Center for Regional Food Studies and the propagation, outplanting, monarch egg emerging mutualisms to restore. Bridging W.K. Kellogg Endowed Chair in Sustain- and larval host plant monitoring, and adult the gaps that exist between current ex- able Food Systems at the University of tagging. These workshops have addressed tractive human economic structures and Arizona. Nabhan is also co-founder of the the need to look beyond milkweed alone restoration has the potential for bringing Forgotten Pollinators Campaign and Make and devise restoration efforts that support wholly new economic systems into exis- Way for Monarchs. Author or editor of two the whole lifecycle of not only monarch tence. Restorative economic structures can books, several monographs, and journal butterflies, but of all migratory pollinators. benefit local communities and reinforce articles on pollinator–plant interactions, Other efforts have also fostered pheno- their relationship with protected areas by he manages several pollinator gardens logical data sharing through the Nature’s strengthening the role that protected areas and hedgerows around his orchard in Notebook social media platform of the play in promoting the connectivity of pol- Patagonia, Arizona.
Volume 36 (4), 2016 Natural Areas Journal 495 LITERATURE CITED restoration of food webs. Philosophical Memmot, J., P.G. Graze, N. Waser, and M. Price. Transactions of the Royal Society of London 2007. Global warming and the disruption of plant-pollinator interactions. Ecological Abrol, D.P. 2012. Pollination Biology: Bio- Biological Sciences 364(1524):1803-1806. Letters 10:710-717. diversity Conservation and Agricultural [DOI] US Department of the Interior. 2015. Production. Springer, The Netherlands. National Seed Strategy for Rehabilitation Menz, M.H., R.D. Phillips, R. Winfree, C. Kremen, M.A. Aizen, S.D. Johnson, and Aizen, M.A., C.L. Morales, and J.M. Morales. and Restoration.
496 Natural Areas Journal Volume 36 (4), 2016 Minckley, L. Gass, L, C. Tolle, and M. Coe. Miller-Rushing, and P. Del Tredici. 2004. Early detection of invasive plants–Princi- 2014. Remote sensing analysis of riparian Herbarium specimens demonstrate earlier ples and practices. US Geological Survey vegetation response to desert marsh resto- flowering times in response to warming Scientific Investigations Report 2012-5162. ration in the Mexican Highlands. Ecological in Boston. American Journal of Bota-
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