Chapter THIRTEEN
Conservation Perspectives*
REVIEW OF NEW SCIENCE AND PRIMARY THREATS TO GOLDEN-WINGED WARBLERS
Ronald W. Rohrbaugh, David A. Buehler, Sara Barker Swarthout, David I. King, Jeffery L. Larkin, Kenneth V. Rosenberg, Amber M. Roth, Rachel Vallender, and Tom Will
Abstract. In this penultimate chapter, we examine which holds 95% of the global breeding popula- new perspectives on ecology of Golden-winged tion, we recommend protection and improve- Warblers (Vermivora chrysoptera), review primary ment of existing habitat, whereas we recommend population-level threats, and offer conservation critically needed habitat creation in the Appalachian recommendations. Adequate forest cover and patch- Mountains breeding-population segment. At the level habitat configuration are important for suc- nonbreeding grounds, we recommend protection cessful reproduction and to buffer against negative of humid forest at 700–1,400 m elevation, estab- interactions with Blue-winged Warblers (V. cyanop- lishment of a system of national forest reserves, and tera). We recommend landscape-scale forest cover of promotion of agroforestry, such as Integrated Open 50%–100% and meso-scale (500-m radius) habitat Canopy Coffee. Given that Golden-winged Warblers designs that provide nesting habitat bounded by a likely use a migration pathway across the Gulf of mosaic of structurally diverse, multiple age-class Mexico, which is similar to many other Neotropical forest or connected to such forest by dispersal cor- migrants, we recommend a general strategy of ridors <200 m in length. The primary threat to protecting coastal Gulf of Mexico stopover loca- breeding and nonbreeding Golden-winged Warbler tions. Last, protection of inland migration pathways populations is land-use change, resulting in forest such as ridge tops and riparian forests along major conversion to human development and agriculture. river systems could also confer benefits to Golden- In the Great Lakes breeding-distribution segment, winged Warblers.
INTRODUCTION a remarkable life cycle that includes a latitudinal migration covering thousands of kilometers and Devising conservation strategies for Neotropical separate breeding and nonbreeding distributions migrant landbirds, such as Golden-winged with different ecological conditions and threats. Warblers (Vermivora chrysoptera), is complicated by The diverse science presented in this Studies in
* Rohrbaugh, R. W., D. A. Buehler, S. B. Swarthout, D. I. King, J. L. Larkin, K. V. Rosenberg, A. M. Roth, R. Vallender, and T. Will. 2016. Conservation perspectives: Review of new science and primary threats to Golden-winged Warblers. Pp. 207–215 in H. M. Streby, D. E. Andersen, and D. A. Buehler (editors). Golden-winged Warbler ecology, conservation, and habitat management. Studies in Avian Biology (no. 49), CRC Press, Boca Raton, FL.
207 Avian Biology volume, ranging from regional new perspectives on Golden-winged Warbler con- studies of postfledgling survival to broad inqui- servation needs, including suggestions for updating ries about migratory connections that potentially current management prescriptions, and (2) review stretch from Manitoba to Colombia, underscores primary population-level threats and offer strate- the complexities of understanding Golden- gies for ameliorating these in the context of full winged Warbler ecology and conservation, not life-cycle conservation planning. There is growing only at one point in space or time, but across need to better understand the connectivity among all stages of the annual life cycle—breeding, different life-cycle phases. We have organized this migrating, and nonbreeding. chapter around the breeding, nonbreeding, and During the 1990s and early 2000s, Golden- migrating stages, and identify potential linkages winged Warbler conservation efforts were oppor- where possible. We conclude with a discussion of tunistic, site-specific, and largely focused on the the need for quantitative, full life-cycle models to Appalachian Mountains. Researchers and manag- identify spatiotemporal population constraints and ers, often working at local scales, protected and more efficiently direct conservation resources for maintained human-modified (e.g., utility rights- the greatest positive impact on the global Golden- of-way and surface mines) and natural (e.g., for- winged Warbler population. ested wetlands) habitats occupied by breeding Golden-winged Warblers (Canterbury and Stover 1999, Confer and Pascoe 2003, Kubel and Yahner BREEDING 2008). Recently, the first guide to Best Management Practices (Bakermans et al. 2011) and comprehen- New Conservation Perspectives sive conservation plan (A. M. Roth et al., unpubl. Status and Distribution plan) have taken a more systematic, distribution- wide approach to Golden-winged Warbler conser- Effective conservation planning requires detailed vation. A. M. Roth et al. (unpubl. plan) provided knowledge about the distribution and abundance a strategic, spatially explicit approach to setting of target organisms on the landscape, especially population and habitat goals, identifying threats, as populations rapidly decline or undergo geo- delineating high-priority focal areas, and making graphic shifts in response to environmental habitat management recommendations. Guidance changes (Faaborg et al. 2010). Rosenberg et al. provided by these publications has been used (Chapter 1, this volume) point out the inadequacy across the breeding distribution to improve and of available monitoring programs to track current create habitat. For example, the Golden-winged population trends and distribution shifts in patch- Warbler is one of seven species targeted for con- ily distributed Golden-winged Warbler popula- servation via the U.S. Department of Agriculture, tions. The North American Breeding Bird Survey Natural Resource Conservation Service’s Working is now ineffective at monitoring Golden-winged Lands for Wildlife program. In the Appalachian Warbler population trends and distribution in Mountains during 2012–2015, the working lands the Appalachian Mountains breeding-distribution program created 3,700 ha of Golden-winged segment because birds are detected on too few Warbler habitat on private lands by using science- survey routes. The same issue is a concern in por- based habitat management prescriptions based on tions of the Great Lakes breeding-distribution seg- Bakermans et al. (2011, 2015) and A. M. Roth et al. ment, and the problem will likely become more (unpubl. plan). systemic in coming years as fewer Golden-winged The new science in this volume provides fresh Warblers are available to be detected on each route. viewpoints on the challenges facing Golden- A related issue is the lack of knowledge about what winged Warbler populations and the strategies is driving population dynamics and shifts in dis- required to implement effective conservation prac- tribution of Blue-winged Warblers (V. cyanoptera). tices. Continued steep population declines in the Hybridization and competitive exclusion by Appalachian Mountains breeding-distribution seg- Blue-winged Warblers may be drivers of Golden- ment and broadening declines in the Great Lakes winged Warbler population declines (Buehler breeding-distribution segment emphasize the et al. 2007). However, few research projects and urgency in addressing known threats. In this chapter, no targeted monitoring projects for Blue-winged we (1) examine results from this volume that yield Warblers have been undertaken in the past decade.
208 STUDIES IN AVIAN BIOLOGY NO. 49 Streby, Andersen, and Buehler This basic lack of data is an obstacle to under- at 75%, as occupancy has not been shown to standing Golden-winged Warbler ecology and decline above this percentage (Thogmartin 2010; population dynamics at a distribution-wide scale Chapter 3, this volume). Moreover, a recent study where it is difficult to compare the relative influ- that examined Golden-winged Warbler habitat ence of habitat loss, nonbreeding-season survival, use in New York and Pennsylvania suggests work- and climate change against the influence of inter- ing in landscapes with >70% forest cover (Wood actions with Blue-winged Warblers. et al. 2016). Also, in light of a positive correlation Rohrbaugh et al. (2011) developed a spatially between Blue-winged Warblers and agricultural balanced, occupancy-based monitoring program and human-developed landscapes, conservation for Golden-winged Warblers in the Appalachian projects in landscapes (2.5-km scale) with >25% Mountains breeding-distribution segment. We combined agricultural and urban cover should be recommend establishment of a similar standard- considered lower priority relative to those in land- ized, distribution-wide program capable of track- scapes with <25% of these cover types. One excep- ing Golden-winged and Blue-winged Warbler tion to this recommendation would be projects breeding populations at multiple spatial scales. A focused on reforesting large portions of open land- standardized protocol will allow biologists, man- use types, such as reclaimed surface mines that are agers, and ultimately policy makers to measure widespread in some portions of the Appalachian population response to management actions and Mountains breeding-distribution segment. refine conservation strategies. Forest that is more mature than that used for primary nesting sites is essential, not only in the larger landscape, but also adjacent to Golden- Habitat Requirements and Reproduction winged Warbler breeding territories, where it has Emerging science documents the importance of been shown to be used by adults and is important adequate forest cover at all spatial scales for suc- for fledgling survival (Streby et al. 2014; Chapters cessful Golden-winged Warbler reproduction and 5, 8, and 9, this volume). The results underscore possibly as a buffer against negative interactions the importance of considering not only cover- with Blue-winged Warblers (Streby et al. 2014; type composition, but also configuration within Chapters 3, 5, 8, and 9, this volume). Crawford and among Golden-winged Warbler management et al. (Chapter 3, this volume) reported that land- sites. To better incorporate adult and postfledging scape-scale settlement patterns of Golden-winged habitat requirements, mesoscale habitat designs Warblers were positively associated with increas- (e.g., within 500-m radius) should provide poten- ing forest cover and higher elevations but nega- tial nesting habitat in shrubland or young forest tively associated with increasing agriculture and that is bounded by structurally diverse, multiple human development. In contrast, Blue-winged age-class forest (at least one home-range size or Warblers showed the opposite relationship with ≥6 ha, see Chapter 5, this volume) or connected the same covariates and were more commonly to such forests by dispersal corridors no longer associated with agriculture. These new findings than 200 m (Chapters 5 and 10, this volume). are important in understanding and mitigating Functionally, conservation plans should maintain for land-use patterns at landscape scales, which dynamic forested landscapes with a shifting mosaic are driving interspecific spatial interactions and of forest-patch sizes and ages, where the interior of may facilitate competitive exclusion or hybridiza- clustered young forest patches is <200 m from the tion. For example, in the absence of a strong ele- edge of surrounding older age-class forest. vational gradient, does an increase in agricultural cover in the landscape facilitate co-occurrence Primary Threats and Conservation Actions or increased frequency of hybridization between Golden-winged and Blue-winged Warblers? The primary threat to Golden-winged Warbler A. M. Roth et al. (unpubl. plan) recommended breeding populations is land-use change through focusing Golden-winged Warbler breeding habitat conversion of forest to agriculture or other human management on sites with 50%–75% forest cover development, resulting in habitat loss and reduc- within 2.5 km. Although this recommendation is tion in habitat quality by creating inappropriate consistent with results in Crawford et al. (Chapter landscape and patch-level configurations. These 3, this volume), we see no reason to cap the range landscape changes facilitate negative interactions
Conservation Perspectives 209 with Blue-winged Warblers (Chapters 3 and 4, 2. Prevent a net loss of habitat, especially on this volume) and impair reproduction and fledg- private lands, which support about 70% of ling survival (Chapters 8 and 9, this volume). the current breeding distribution (North Compounding the problem of land-use change, American Bird Conservation Initiative an overall maturing of forest within significant 2013). parts of the Golden-winged Warbler’s breeding 3. Protect significant populations on distribution, combined with lack of natural dis- public land, particularly in places where turbances and forest management, has reduced surrounding unprotected land is likely to regeneration of early successional habitats used by undergo extensive land-use change. Golden-winged Warblers for nesting. 4. Increase cooperation among conservation A. M. Roth et al. (unpubl. plan) set a goal of groups to ensure management for associated restoring the global Golden-winged Warbler pop- species, such as American Woodcock ulation from the current estimate of 414,000 to (Scolopax minor) also benefits Golden-winged 621,000 individuals by 2050. Currently, the Great Warblers (Bakermans et al. 2015). Lakes breeding-distribution segment is estimated to hold 95% of the global breeding population, 5. Work collaboratively with Canadian with only 5% in the Appalachian Mountains officials to facilitate population expansion breeding-distribution segment (Chapter 1, in northern latitudes where genetic purity this volume). The imbalance is increasing as of subpopulations is still high (Vallender populations are declining more rapidly in the et al. 2009; Chapter 4, this volume). Appalachian Mountains breeding-distribution Conservation actions in the Appalachian segment than in the Great Lakes segment. Data Mountains breeding-distribution segment are from the U.S. Forest Service’s Forest Inventory necessary to maintain the species within portions Analysis indicate that opportunities to create new of its historical breeding distribution (Chapter 1, habitat are greater in the Appalachian Mountains this volume). Nonbreeding season loss of indi- segment, where presently only about 7% of for- viduals from the vanishingly small Appalachian est is suitable for Golden-winged Warblers com- Mountains breeding-distribution segment to pared with 19% suitable forest in the Great Lakes rapid habitat loss or stochastic events could hasten segment (A. M. Roth et al., unpubl. data). A. M. local extirpations and hinder population recov- Roth et al. (unpubl. plan) suggested that land- ery. The most important immediate actions in scape-scale forest management should strive to the Appalachian Mountains breeding-distribution perpetually keep 15%–20% of forest in an early segment are to: successional stage for Golden-winged Warblers and associated bird species. Following this guid- 1. Protect key, high-elevation populations that ance, the proportion of early successional forest in have historically withstood co-occurrence the Appalachian Mountains breeding-distribution with Blue-winged Warblers and that segment could be more than doubled before the remain largely unaffected by hybridization 15%–20% threshold is met, whereas the Great (Dabrowski et al. 2005, Vallender Lakes segment is already near the recommended et al. 2009). maximum. Given the imbalance in initial popula- 2. Increase subpopulations by creating and tion size and opportunities for habitat and popula- maintaining biologically meaningful tion growth, different conservation strategies are amounts of habitat within Golden-winged required to address the threat of land-use change Warbler focal areas (A. M. Roth et al., in each breeding-distribution segment. unpubl. plan) where Blue-winged Warbler The most important conservation actions for co-occurrence is unlikely. Golden-winged Warblers in the Great Lakes 3. Act on new knowledge about linkages breeding-distribution segment are to: between breeding and nonbreeding 1. Improve the quality of existing habitat by populations to enhance nonbreeding altering forest configuration and structure, survival and condition of the Appalachian following recommendations in Roth et al. Mountains breeding-distribution segment (2014, unpubl. plan) and the new science where it occurs during the nonbreeding presented in this volume. season (Chapters 12 and 14, this volume).
210 STUDIES IN AVIAN BIOLOGY NO. 49 Streby, Andersen, and Buehler NONBREEDING In addition to working within protected areas, it is important to provide Golden-winged Warbler New Conservation Perspectives habitat in working lands. Shade coffee represents a Findings from this volume inform conserva- potential strategy for accomplishing conservation tion of Golden-winged Warblers at nonbreeding on working lands because it involves the retention areas in a number of important ways. Rosenberg of trees within areas of coffee production, which et al. (Chapter 1, this volume) provided the first support more biodiversity than other forms of detailed description of the nonbreeding distribu- agriculture. Golden-winged Warblers are reported tion, including areas where the species is most from shade-coffee farms, but these farms may concentrated during the nonbreeding season; provide suboptimal habitat because microhabi- these results are being used to identify focal areas tat features required by Golden-winged Warblers as part of the ongoing development of a non- are seldom present in coffee farms. Moreover, the breeding grounds conservation plan. King et al. cohesion of the mixed species flocks on which (Chapter 2, this volume) reported that Golden- Golden-winged Warblers depend is not main- winged Warblers in Costa Rica, Honduras, and tained in these farms (Pomara et al. 2007; Chapter Nicaragua occupied both regenerating and pri- 11, this volume). Perhaps a more effective option mary forest within a suitable range of elevation is Integrated Open Canopy (IOC) Coffee, where and moisture conditions, bounded by dry forests coffee is grown with sparse or no shade adjacent at lower elevations and cloud forest at upper eleva- to forest patches of equivalent or greater size tions. Edges and canopy gaps with abundant dead that provide habitat for Golden-winged Warblers leaves and vine tangles for foraging were impor- (Chapter 2, this volume). In addition to promot- tant determinants of Golden-winged Warbler ing the conservation of forest habitat required by presence within their nonbreeding distribution Golden-winged Warblers and other species, IOC (Chapter 2, this volume). coffee increases income to farmers by increasing Observations concerning other aspects of yields and providing a market-based incentive for Golden-winged Warbler nonbreeding ecology forest conservation. have conservation implications. Chandler et al. (Chapter 11, this volume) reported that Golden- Primary Threats and Conservation Actions winged Warblers spent most of their time within mixed-species flocks, within which they defended Quantitative data on Golden-winged Warbler territories from conspecifics. Because individual population limiting factors during the nonbreed- flocks use large areas (~9 ha), and each flock may ing season are lacking, but we presume that the only support a single Golden-winged Warbler, primary threat is loss of forested habitat from con- nonbreeding densities are necessarily low, and version to agriculture and other land uses, simi- thus a large area is required to support their non- lar to known limiting factors for better studied breeding populations. Neotropical migrant species (Johnson et al. 2006). Development of a comprehensive conservation In the middle-elevation humid forest zones occu- strategy for the nonbreeding grounds is a daunting pied throughout the nonbreeding distribution of task because of the number of countries involved Golden-winged Warblers (Chapter 1, this vol- (Chapter 2, this volume). Landscape-scale conser- ume), forest conversion for commodity produc- vation on the nonbreeding grounds will require tion is particularly acute, with rapid recent loss partnering with governments, industries, and of forest occurring in Guatemala, Honduras, and nongovernmental organizations throughout Nicaragua (Cherrington et al. 2011). In Colombia the Golden-winged Warbler’s nonbreeding dis- and Venezuela, most forest conversion occurred tribution. There is urgent need to involve the in the 1980s and 1990s; thus, reduction in non- “Protected Areas Management” departments of breeding Golden-winged Warblers populations Latin American governments. With partnerships, in South America may reflect past loss of forest government officials can incorporate conserva- and may be linked to population declines in the tion recommendations into their protected areas Appalachian Mountains breeding-distribution management plans and train their field biolo- segment (Chapter 1, this volume). In Costa Rica, gists to recognize and manage for Golden-winged forest loss has slowed in the past decade and Warbler habitat. forested corridors are being regenerated in an
Conservation Perspectives 211 attempt to reconnect a system of isolated national planning for Golden-winged Warblers will be parks and preserves (Cherrington et al. 2011). hampered until knowledge gaps during this stage Clearly, any assessment of threats to nonbreed- are addressed. ing populations must account for regional varia- Stable isotope analysis has provided the first tion in land-use change. As part of developing a look at migratory connectivity for Golden-winged nonbreeding grounds conservation strategy for Warblers (Chapter 12, this volume). The geo- Golden-winged Warblers, a country-by-country graphic resolution of the connections is broad, threats analysis was recently completed within the owing to small sample sizes and the uncer- focal areas identified in Rosenberg et al. (Chapter tainty inherent in interpreting isotope data. 1, this volume). Nevertheless, these results provide the first chance Even with limited knowledge, strategies for to link regional Golden-winged Warbler popula- mitigating threats and increasing survival of tion declines with not only breeding ground nonbreeding Golden-winged Warblers can be attributes, but also specific locations and corre- derived from recent studies of nonbreeding dis- sponding habitat conditions at nonbreeding areas. tribution, ecology, and habitat use (Chapters 1, 2, Understanding connectivity is a critical step in and 11, this volume). These actions fall into four making linkages among life cycle stages and dis- broad areas: cerning the interdependence of each stage. New technologies, such as light-level and GPS- 1. Protect remaining primary and second- enabled geolocators, provide great promise for ary humid forests between 700 and developing fine-scale maps of migratory connec- 1,400 m in the Central American high- tivity and stopover sites. These devices have been lands and northern Andes by establishing used to successfully map migratory connectivity national reserves, municipal watershed of Neotropical migrants such as Wood Thrushes protection, and conservation easements. (Hylocichla mustelina) and Purple Martins (Progne subis) Protected areas should be large enough (Fraser et al. 2012, McKinnon et al. 2013). Current to support cohesive mixed-species flocks research with geolocators provides promising within which Golden-winged Warblers results that may soon generate meaningful insights can maintain nonbreeding territories into connectivity patterns in Golden-winged (Chapter 11, this volume). Warbler populations (Chapter 14, this volume). 2. Restore and regenerate forest patches and corridors within focal areas of the nonbreeding grounds, especially near Primary Threats and Conservation Actions occupied Golden-winged Warbler non- Two potential threats to migrating Golden- breeding sites. winged Warblers are loss and degradation of 3. Promote agroforestry practices and migratory stopover habitats and fatal collisions other land uses that are compatible with with anthropogenic structures (Arnold and Zink nonbreeding Golden-winged Warblers, 2011, Loss et al. 2014). Rosenberg et al. (Chapter 1, especially IOC coffee, which encourages this volume) and Hobson et al. (Chapter 12, this retention of intact forest patches in the volume) speculated that Golden-winged Warblers landscape (Chapter 2, this volume). mainly use a migration pathway across the Gulf of Mexico during spring and fall. A large num- ber of Neotropical migrant species use a similar MIGRATING pathway (La Sorte et al. 2014). Thus, a general strategy of protecting coastal stopover sites that New Conservation Perspectives have been identified as being critical for other Of the three life-cycle stages for Golden-winged Neotropical migrants along the Gulf Coast of the Warblers, migration is the least studied and con- U.S., Mexico, and Central America, and known sequently has the largest number of knowledge inland migration pathways such as ridge tops and gaps (Chapter 14, this volume). Given that the riparian forests along major river systems, could migration period may be when mortality for enable Golden-winged Warbler migration. For migratory birds is greatest (Sillett and Holmes Golden-winged Warblers and other migrants that 2002), comprehensive full life-cycle conservation spend the nonbreeding season in South America,
212 STUDIES IN AVIAN BIOLOGY NO. 49 Streby, Andersen, and Buehler stopover areas and corridors on the north coast necessary information about the extent to of Colombia also might be critical for successful which the Golden-winged Warbler’s population long-distance migration (Bayly et al. 2012). is being limited in each stage of its life-cycle. Collision mortality might pose a significant threat Conservation biologists have recognized the during migration for Golden-winged Warblers. value in considering all segments of a migratory Arnold and Zink (2011) identified Golden-winged species’ annual cycle to develop full life-cycle Warblers as having a greater than expected inci- population models and conservation strate- dence of collision at communications towers, and gies (Sherry and Holmes 1995, Faaborg et al. Loss et al. (2014) estimated that Golden-winged 2010). This full life-cycle approach has illumi- Warblers had a collision risk with buildings (win- nated biological and geographical relationships dows) that was 35.3 times greater than a migrant between nonbreeding grounds and breed- species with average risk. Moreover, Loss et al. ing grounds. For example, Norris et al. (2004) (2014) suggested that building collisions may found that variation in site quality of American contribute to or exacerbate overall Golden-winged Redstart (Setophaga ruticilla) nonbreeding loca- Warbler population declines. tions carried over into the breeding season, Lacking specific information for Golden-winged causing impacts to reproductive fitness. New Warblers, the most straightforward strategy to help understanding about population limitations ensure safe migration passage is to support existing at various stages throughout the full life cycle efforts that are already protecting critically impor- opens novel opportunities to create dynamic tant stopover habitats and influencing policies conservation plans that identify and mitigate for focused on reducing collision risk with buildings population constraints in both space and time. and towers. The most relevant initiatives include the Traditional conservation strategies for migratory following: birds have mostly relied on the broad scheme of protecting and creating habitat within the 1. The Joint Venture network operated breeding distribution. The traditional approach by U.S. Fish and Wildlife Service and can increase breeding population density and American Bird Conservancy, especially the perhaps fecundity, but source–sink population Gulf Coast, East Gulf Coastal Plain, and models (Donovan and Thompson 2001) have Appalachian Mountains Joint Ventures shown that passerine populations are most sen- 2. The Fatal Light Awareness Program and other sitive to adult and juvenile mortality, which similar programs, which focus on reducing is often highest during migration (Sillett and collisions with buildings and collecting data Holmes 2002). Full life-cycle strategies could on fatal bird strikes help resolve this potential conservation discon- 3. The American Bird Conservancy’s “Bird nect by pinpointing the locations and periods Smart” programs aimed at policy reforms when management action would be most effec- to reduce collision risk at wind turbines, tive, thereby hastening population recovery and buildings, and communications towers maximizing the impact of limited conservation 4. The Midwest Landbird Migration funds (Berlanga et al. 2010). Monitoring Network and other regional Recent, large-scale collaborative research on initiatives focused on improved under- Golden-winged Warblers has generated new standing of migratory landbird ecology demographic and movement data required for and conservation developing quantitative, full life-cycle popu- lation models. The Golden-winged Warbler research community has collected useful data CONCLUSIONS for such models in both the breeding and nonbreeding periods, and ongoing research Call for Full Life-Cycle Conservation (Chapters 12 and 14, this volume) will soon As evidenced from the extensive field projects provide data to parameterize the demographics conducted by a diversity of research partners of migration. Given new information, and the in this volume, the Golden-winged Warbler is urgent need to reverse Golden-winged Warbler becoming one of the most studied Neotropical population declines, we suggest a collaborative migrant warbler species. Yet, we still lack research effort to begin developing quantitative
Conservation Perspectives 213 full life-cycle models that can adaptively inform Canterbury, R. A., and D. M. Stover. 1999. The Golden- existing conservation plans. winged Warbler: an imperiled migrant songbird of In the meantime, the lack of such models should the southern West Virginia coalfields. Green Lands not preclude immediate conservation action to 29:44–51. address known threats in each life-cycle stage. Cherrington, E. A., B. E. Hernandez, B. C. Garcia, M. O. Conservation actions can protect existing popu- Oyuela, and A. H. Clemente. 2011. Land cover change lations, reduce mortality, and increase reproduc- and deforestation in Central America. CATHALAC, tion, while building capacity, infrastructure, and Panama City, Panama.
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