Managing Wetlands for Waterbirds: How Managers Can Make a Difference in Improving Habitat to Support a North American Bird Conservation Plan

R. Michael Erwin Murray K. Laubhan John E. Cornely Dana M. Bradshaw

Abstract—Wetlands are the most productive ecosystems in the to ensure that a diverse array of waterbird species will benefit. world, yet they have suffered more loss and degradation than any Efforts also should be devoted to developing similar partnerships in other ecosystem. Not surprisingly, 50% (29 of 58) of all the bird areas where important wetland resources exist but no Joint Ven- species in the United States (excluding Hawaii and territories) that tures are planned. are listed either as federally threatened or endangered, or are on the U.S. Fish and Wildlife Service 1995 List of Migratory Nongame Birds of Management Concern, occupy wetland or aquatic habitats Although wetlands are widely recognized as among the even though many remaining wetlands across the North American most productive ecosystems globally, wetland loss continues landscape already are managed primarily for waterbirds. Some of both in North America and throughout the world, owing these wetlands are administered by federal and state entities (e.g., largely to a burgeoning human population and the concomi- national wildlife refuges, national and state parks, state wetland tant conversion of natural wetlands for human uses. For management areas) or are maintained on private lands through example, the Bay of Fundy is a critical habitat for shorebirds federally supported restoration and enhancement programs (e.g., during migration (Morrison and others 1994) but is threat- Conservation Reserve Program, Wetland Reserve Program, Water- ened with both hydroelectric development and harvesting of fowl Production Areas, and Partners for Wildlife). Private organiza- polychaete worms (major shorebird prey) for sport fishing tions, such as the National Audubon Society, The Nature Conser- (P. Hicklin, Canadian Wildlife Service, personal communi- vancy, and private hunting clubs also own wetland areas that are cation). Similarly, James and western Hudson Bays are the managed specifically to benefit wildlife. If management philoso- subjects of major water development planning, despite their phies are altered to consider the entire complex of wetlands, many roles as major nesting and migration areas for geese and a wetlands can provide benefits to a broad array of waterbirds, as number of species of shorebirds. The prairie pothole region opposed to just one or a few species. However, challenges for natural of Saskatchewan and Manitoba are part of a Canadian resource managers are in forming partnerships with owners-man- prairie habitat joint venture (JV) under the North American agers of wetlands where the objectives are not primarily wildlife Waterfowl Management Plan (NAWMP[USFWS 1986]). The oriented. These owners or managers need to be included in wetland region has been recognized internationally as one of the training workshops in an attempt to educate them about wetland premier nesting grounds for many diving and dabbling values and secondary wildlife benefits that may be derived in ducks, and it also provides habitat for endangered Piping flooded agricultural lands, aquaculture ponds, altered coastal Plovers (Charadrius melodus). This area historically has marshes (mosquito control), and salt evaporation ponds. In some faced numerous conversions of potholes to croplands. The cases, compensation for crop damages by wildlife may be a neces- western Canadian regions of most concern are the Fraser sary part of any cooperative agreements. In the development of a River corridor and delta and the adjacent Vancouver Island North American Bird Conservation Plan, we propose a four-step region. Development and growth is rapid in that region, and approach and recommend that emphasis be placed on working with intense logging occurs along the Fraser. The region is well Joint Ventures of the North American Waterfowl Management Plan known for its wintering waterfowl and marine bird concen- trations (Vermeer and Butler 1989). Similar examples are numerous throughout most of North America. However, In: Bonney, Rick; Pashley, David N.; Cooper, Robert J.; Niles, Larry, eds. 2000. Strategies for bird conservation: The Partners in Flight plan- during the past two decades, many federal, provincial, and ning process; Proceedings of the 3rd Partners in Flight Workshop; 1995 state programs have been initiated to provide economic October 1-5; Cape May, NJ. Proceedings RMRS-P-16. Ogden, UT: U.S. incentives for wetland conservation in an attempt to achieve Department of Agriculture, Forest Service, Rocky Mountain Research Station. a “no net loss” of wetlands (The Conservation Foundation R. Michael Erwin, Biological Resources Division, USGS, Patuxent Wild- 1988). These earlier losses of wetlands, and recent changes life Research Center-Charlottesville Office, Department of Environmental Sciences, Clark Hall, University of Virginia, Charlottesville, VA 22903. in the status of wetlands, have broad implications to wildlife. Murray K. Laubhan, Biological Resources Division, USGS, Midcontinent In this paper we review the status of wetlands as habitats Ecological Science Center, Fort Collins, CO 80525. John E. Cornely, U.S. for waterbirds (defined as waterfowl, colonial waterbirds, Fish and Wildlife Service, Region 6, P.O. Box 25486, Denver Federal Center, Denver, CO 80225. Dana M. Bradshaw, Center for Conservation Biology, shorebirds, and rails and allies). We focus on species whose College of William and Mary, Williamsburg, Virginia 23185.

82 USDA Forest Service Proceedings RMRS-P-16. 2000 status is of concern either regionally or nationally, and on aquatic-dependent, while the comparable figures from the current wetland management practices that are detrimen- OMBM list are 14 of 23 species. tal to wetland birds. We identify gaps in our knowledge of The habitats used by these species suggest that the major- ecological principles for managing habitats for waterbirds, ity are associated with freshwater (interior) marshes or and conclude with recommendations for improving wet- coastal beaches and/or islands. These are habitats that have land management to enhance waterbird populations. been among the most affected by humans, either by direct disturbance (beaches) or indirectly by agricultural conver- sions (freshwater marshes). In addition, interior marshes and Status of Species and Associated coastal areas often are intensively managed, suggesting that Wetlands ______current habitat management practices should be evaluated relative to providing benefits to a diversity of species. For We consulted two recent publications to identify the major example, many of the major wetland complexes listed for the waterbird species of concern in North America: The 1994 list U.S. already are included under JVs in the NAWMP (table 2). of endangered and threatened wildlife and plants (USFWS However, the Atlantic Coast Habitat Joint Venture focuses on 1994b) and the 1995 List of Migratory Nongame Birds of American Black Ducks (Anas rubripes). Separate (but un- Management Concern (Office of Migratory Bird Manage- equal) programs are directed at restoration of the endangered ment [OMBM] 1995). These lists indicate that more than Piping Plover, and at monitoring certain declining colonial 50% of birds of concern in the U.S. are associated with either waterbird species in the mid-Atlantic barrier region. wetlands or aquatic habitats (table 1) (Canada and Mexico During the past decade, however, the scope of habitats and do not have formal endangered species listings). The federal avian species being considered has been increasing. For endangered and threatened list includes 16 of 35 species (not example, discussions are under way (C. Hunter, USFWS, including Hawaii or trust territories) that are wetland or personal communication) to form a JV for part of the extensive

Table 1—List of wetland/aquatic bird species of concern in the United States.

Habitat Common name Scientific name Wetland Aquatica Federal threatened/endangered b California Brown Pelican Pelecanus occidentalis X Wood Stork Mycteria americana X Spectacled Eider Somateria fischeri X Everglade Snail Kite Rostrhamus sociabilis plumbeus X Bald Eagle Haliaeetus leucocephalus X Light-footed Clapper Rail Rallus longirostris levipes X Yuma Clapper Rail Rallus longirostris yumanensis X Whooping Crane Grus americana X Mississippi Sandhill Crane Grus canadensis pulla X Western Snowy Plover Charadrius alexandrinus nivosus X Piping Plover Charadrius melodus X (Interior) Least Tern Sterna antillarum athalassos X California Least Tern Sterna antillarum browni X Roseate Tern Sterna dougallii dougallii X Marbled Murrelet Brachyramphus marmoratus marmoratus X Cape Sable Seaside Sparrow Ammodramus maritimus mirabilis X USFWS Listc Common Loon Gavia immer X American Bittern Botaurus lentiginosus X Least Bittern Ixobrychus exilis X Reddish Egret Egretta rufescens X White-faced Ibis Plegadis chihi X Trumpeter Swan Cygnus buccinator X Northern Harrier Circus cyaneus X Red-shouldered Hawk Buteo lineatus X Black Rail Laterallus jamaicensis X Snowy Plover Charadrius alexandrinus X Bristle-thighed Curlew Numenius tahitiensis X Black Tern Chlidonias niger X Cerulean Warbler Dendroica cerulea X Seaside Sparrow Ammodramus maritimus X

a"Aquatic” refers to primary use of lake, river, and/or marine habitats. bUnited States Fish and Wildlife Service (1994). cOffice of Migratory Bird Management (1995).

USDA Forest Service Proceedings RMRS-P-16. 2000 83 Table 2—Primary wetland regions for waterbird conservation in North America.

Country Complex Canada Bay of Fundy James Bay-W. Hudson Bay Prairie potholes (S. Saskatchewan, Manitoba) Fraser River corridor-delta Vancouver Island region United States Atlantic coastal barriers Forested wetland of the southeast-lower Mississippi River Prairie potholes/Rainwater Basins Riparian corridors-Intermountain west Copper River delta, Alaska Yukon River delta, Alaska Playa Lakes Region (Texas, Oklahoma, S. Colorado) West coast estuaries Agricultural valleys-West Mexico Ensenada del Pabellon and Boca de la Barra Marismas Nacionales Usumacinta-Grijalva delta Laguna de Terminos Rio Lagartosa Rio de Celestuna Sian Ka’ana Laguna Babicoraa

aDesignated as a Faunal Reserve or international Man and Biosphere Reserve (UNESCO).

forested wetlands in the southeastern U.S. from Virginia to congressmen refer to as the Alaska Oil Reserve. Special Florida where forested wetland loss has resulted in marked mention also should be made of the Copper River delta, declines of wintering waterfowl and certain songbirds such as which is critical to enormous numbers of migrating shore- the Swainson’s Warbler (Lymnothlypis swainsonii). The lower birds in spring and fall (Gill and others 1995). It also is Mississippi River supports a very active JV that includes important to many species of geese and ducks. waterfowl, shorebirds, and Neotropical migrants. In the in- In Mexico, a number of important wetland areas for terior, agriculture has been modified to be more “friendly” to waterbirds, especially waterfowl, have been identified un- wetland birds in several JV areas: The Playa Lake region of der the NAWMP. To date, however, none has been desig- Texas and southern Colorado, the Prairie Potholes of the nated as a JV area (USFWS 1995). Several, however, have Dakotas and Montana, and the Rainwater Basins in Ne- been designated by UNESCO as Man and Biosphere Re- braska. The Playas are important waterfowl wintering habi- serves or as Faunal Reserves by Mexico (Baldassarre and tat, while the latter two areas are critical for breeding and others 1989) (table 2). Of hemispheric importance is the migrating waterfowl and shorebirds. Usumacinta-Grijalva delta region, which exceeds the size Farther west, the riparian corridors of the arid intermoun- and significance of the present-day Everglades region in tain west and the large agricultural valleys (e.g., Central, Florida (Ogden and others 1988). It is threatened by conver- Sacramento, and San Luis in California, and Willamette in sion to agricultural uses and dam construction. The north- Oregon) represent important wintering and migration habi- ern coastal lagoons of Rio Lagartos and Rio Celestun are tat for waterfowl and shorebirds, respectively. Metal con- important to the rare Greater Flamingo (Phoenicopterus tamination (selenium and boron) of irrigation drainwater in ruber) and are major wintering areas for several species of the agricultural basins of the West has stirred major contro- waterfowl migrants from the U.S. versies concerning whether wetlands in wildlife refuges should become sumps. Along the west coast, the few estuar- ies with remaining wetlands (San Francisco Bay, San Diego Wetland Practices Unfavorable to Bay, Puget Sound, Fraser River delta and corridor) require Waterbird Conservation ______constant vigilance to protect against further loss and degra- dation. Recently, the USFWS named Puget Sound as a In this section, we highlight some current practices national estuary program. occurring in wetlands that adversely affect either the In Alaska, numerous wetlands abound both on the coast quality or quantity of wetland habitat available to and on interior wildlife refuges and parks; most of these waterbirds (table 3). The principal areas affected also are are under no immediate threats. The major exception is indentified. Where possible, we make recommendations for the Arctic National Wildlife Refuge, which some U.S. improvement.

84 USDA Forest Service Proceedings RMRS-P-16. 2000 Table 3—Wetland practices unfavorable to waterbirds and wetland conservation in North America.

All Barrier Coastal Palustrine Riparian Playas- Issue wetlands beaches marshes forests wetlands potholes 1. Federal-state wetland policy x 2. Contaminants x x x 3. Human disturbance x x 4. Timber harvest xx 5. Grazing x (geese) x (cattle) 6. Drainage-agriculture x 7. Exotic species x 8. Single-species (or group) management x

Current Practices Timber Harvesting on Private Lands—Especially in Canada and the southeastern U.S., timber harvesting in Navigation and Flood Control—The hydrology of many palustrine forested regions has resulted in large losses of rivers has been severely modified. In many cases, peak wetlands for wildlife (Erwin 1996). In addition, many remain- discharges have been reduced and low flows have been ing forested wetlands have been fragmented—or natural increased, resulting in more stable hydroperiods among hydrologic regimes have been disrupted—by road construc- seasons and years. Although moderation of flows improves tion for timber harvesting. Conservation organizations need efficiency of hydroelectric power generation, provides more to develop partnerships with private organizations and corpo- reliable navigation, and reduces the threat of floods, many rations to determine market-compatible methods of extrac- habitats important for avian species have been destroyed or tion that are more “friendly” to wildlife. This effort also will their value severely decreased. However, recent attempts to require more education of “corporate America” (as well as coordinate water discharges to facilitate reestablishment of corporate Mexico and Canada) about the values of biodiversity. riparian wetland types and regeneration of woody riparian Single-Species Management in Forested Wetlands— species have met with some success. Additional effort should Wildlife management in forested wetlands of the Missis- be directed toward cooperation among responsible agencies sippi River corridor and throughout much of the south and and individuals with respect to alternative methods of river northeastern U.S. has concentrated on “greentree reser- management. voirs” where the primary focus has been to produce Wood Human Disturbances Along Beaches and Islands in Ducks (Aix sponsa) (Fredrickson and others 1990). The the Coastal Barrier Regions—Increases in population Wood Duck has been a major “target species” for both state and recreational demands by boaters continue, especially in and federal refuge lands. Although “woodies” have become the Atlantic and Gulf coasts of the U.S. In the Yucatan region increasingly important to waterfowl hunters as other spe- of Mexico, resort development and ecotourism continue to cies have declined over the past decade, managing for one grow. Increasing access to formerly remote mangrove is- species is usually accomplished at the expense of many lands by personal watercraft (e.g., Jet Skis) represents an others in the ecosystem. Within a complex of impoundments, increasing threat to nesting herons, spoonbills, storks, peli- managers should seek to diversify water management sched- cans, and cormorants in Florida, Texas, Mexico, and other ules to maintain current forest composition and structure as tropical coastal resort areas (Erwin and others 1995; Rodgers well as to promote natural regeneration. and Smith 1995). These threats call for additional regula- Grazing in Riparian Zones Along Western Rivers— tory actions regarding land access as well as environmental Exclosures or other methods of preventing livestock access education, especially for boaters who may be oblivious to to free-flowing rivers of the arid west are essential to ensur- bird conservation needs. ing stream water quality and to resisting further invasions Mosquito Control in Coastal Marshes—Historically, of exotic plants. This problem is critical in the western U.S. coastal marshes were diked to stabilize water levels, thereby (Naiman and others 1995) and especially western Mexico. reducing the magnitude of mosquito problems. Current Water Rights of Wildlife—In the western U.S. and mosquito control in most coastal areas combines use of prairie regions of Canada, water rights among state, provin- organophosphate pesticides as adulticides with some form of cial, and local interests are politically charged. Wetland marsh management. The latter often involves use of heavy managers need to argue that wetland wildlife also has a equipment to create high-marsh ponds and canals that allow “share” in this essential commodity, and that refuges should fish to access mosquito breeding areas (Meredith and not simply become shunts for receiving irrigation drainwater Stachecki 1985). Although this practice may be ecologically that will adversely affect water quality. Concentrations of superior to using dikes and chemical pesticides, in many metals (e.g., selenium) in drainwater in vast regions of the areas the net benefit to waterbirds and other wildlife may be arid western U.S., from California across Nevada to Wyo- marginal at best (Erwin and others 1994). Because few ming, have compromised the wildlife quality of many refuge natural coastal marshes remain along the east and Gulf wetlands and other non-federal impounded wetlands coasts of the U.S., marsh manipulations should be restricted (Ohlendorf and others 1986). to those areas that already have been severely altered by humans, and where mosquitoes are a major nuisance.

USDA Forest Service Proceedings RMRS-P-16. 2000 85 Protecting Small Pothole Complexes in the Prairie songbirds are well monitored by the annual roadside Breed- Regions—In Canada and the U.S., valuable gains have ing Bird Survey, wetland species are much less covered been made to set aside marginal agricultural lands for because of lack of road access to most wetland areas. The wildlife. Further efforts are needed to insure that large International Shorebird Survey is undergoing a review (B. complexes of these small wetlands are maintained to con- Harrington, personal communication) and a colonial serve the diversity of habitat needed by nesting waterfowl, waterbird national database is under development within shorebirds, rails, and grebes. Farmers must have continued the Biological Resources Division of the U.S. Geological financial incentives (e.g., the Conservation Reserve Pro- Survey (BRD) since the National Audubon Society database gram under the Food Act of 1985) to maintain the successes was terminated in the late 1980s. A marsh bird (rails, achieved to date. The lessons learned in Canada and the U.S. bitterns, grebes) survey has been under discussion within need to be applied in Mexico, where farmers presently have BRD (S. Droege, USGS, personal communication) because of few economic incentives to save wetlands. the dearth of information on this group of birds, some of which are hunted annually. Currently much less informa- Runoff and Sedimentation—In the Playa Lakes region tion is available on either migration concentration areas or in Oklahoma, west Texas, and southeastern Colorado, water on important wintering sites of colonial waterbirds, rails, quality suffers in many areas due to feedlot manure runoff and bitterns. All of these major groups are lacking in com- and sedimentation into the lakes from livestock areas. More prehensive survey coverage to allow for national assess- effective buffering is needed. Cotton crops are ecologically ments of trends in populations. dangerous because of the intensive pesticides they require, and because of soil erosion resulting from lands left barren Fragmentation Effects—Although the effects of forest much of the year. Alternative land uses are advised. fragmentation have been well studied for upland bird spe- cies (see Askins and others 1990 for a review), much less Pesticides—Modern organophosphate pesticide applica- information is available on the effects of wetland fragmen- tions, although not as toxic as organochlorines (Grue and tation. Research is required to investigate how changing others 1983), are still problematic throughout most agricul- sizes and patterns of distinct wetlands (e.g., potholes) affect tural areas in North America. In the Rainwater Basins of their use by a variety of wetland birds. In addition, the Nebraska, in addition to heavy pesticide applications, a fragmentation of expansive areas of marshes (e.g., by mos- number of exotic plants also have invaded. More biological quito control excavation) may adversely affect their use as control of pest species is strongly encouraged. Water quality breeding habitat for some species (Burger and others 1979; in these small basins has suffered. Erwin and others 1994). Large-Scale Experimentation in Wetland Manage- Major Gaps in Our Knowledge to ment—Seldom are well-controlled experiments performed Effectively Manage Wetlands for in wetlands. Impoundment water management, pesticide applications, Phragmites control, mosquito ditching, and Wildlife ______marsh burning all are examples of activities for which controlled and replicated experimentation is needed to criti- We identify below some major gaps in our understanding cally evaluate different management practices in wetlands. of wetland wildlife and its habitat needs, how wetlands These approaches should follow an adaptive resource man- function as quality wildlife habitat, and how to more effec- agement strategy (Walters 1986; Conroy, this proceedings). tively integrate and communicate our knowledge to manag- ers and the public. Training of Professionals—Many private, state, pro- vincial, and federal biologists and managers involved in either the conservation or regulation of wetlands possess Major Gaps in Knowledge only a basic understanding of wetland ecology. More ad- Integration of Wetlands Within the Landscape Ma- vanced training is required to understand the ecological trix—Often, studies of habitats have focused only on the processes in wetlands and to understand the significance of individual habitat type: Wetlands, grasslands, forest type, wetland complexes over a larger landscape. Geographic and so forth. Further, information regarding differential use information systems are becoming vital tools for managers of wetland types by wetland-dependent species is lacking. to learn the basics of ecosystem and landscape management. Little attempt has been made to determine how the juxtapo- Public Relations Concerning Wetlands—For the pub- sition of various wetland or habitat types affects their lic to appreciate attempts to conserve wetlands, much more respective uses by wildlife. Research is required to deter- emphasis must be placed on teaching the values of wetlands mine how local (e.g., wetland complex) and regional (e.g., to the citizenry of Canada, the U.S., and Mexico (Conserva- flyway) landscape processes affect patterns of use. tion Foundation 1988). Especially considering the antici- Regional and National Monitoring of Populations— pated demands for fresh water (water consumption in the Wintering locations of most waterfowl have been identified U.S. has doubled since the 1940s and may double again in as part of the regular inventory of states and USFWS flyway the next 20 years [Naiman and others 1995]), the public councils. The major shorebird concentration areas have must develop an appreciation of wetlands for the many been identified by the Western Hemisphere Shorebird Re- ecological, recreation, aesthetic, and public service values serve Network (WHSRN, Myers and others 1987), now part that they hold. Teaching of wetland ecology should be in- of the larger Wetlands for the Americas Program. Although cluded in public school curricula, and should be part of the outreach effort of every scientist and landscape manager.

86 USDA Forest Service Proceedings RMRS-P-16. 2000 Recommendations ______• Training workshops for wetland biologists and managers should be expanded and should include the private sector. Our general recommendations to improve wetland man- Aquaculturists, rice farmers, hunting preserve manag- agement for a wide array of waterbird species are: ers, large ranch owners, and leaders of ecotourism enter- prises should be included in the educational process. • The current JVs in the U.S. under NAWMP should be • Assistance in ecological planning for wetland construc- expanded to include more non-waterfowl avian species. tion or alteration needs to be institutionalized. As part of The Canadian prairie habitat JV and the Lower Missis- a permitting process, regulatory personnel in state, sippi Valley JV have significant shorebird components. provincial, and federal governments should require that They also could be expanded to include colonial a private permit holder consult with professional wet- waterbirds, rails, and bitterns. A single-species or land scientists (certified by the Society of Wetland Man- focal-group approach will achieve only limited success. agers) before embarking on large-scale wetland projects • New JVs and other partnerships should be established such as construction of reservoirs, aquaculture facilities, in regions with no current JVs; this includes all of or irrigation systems. For example, if catfish ponds in the Mexico, parts of eastern Canada, and the southeastern south had been constructed as small (half-acre) ponds, U.S., although the forested wetlands of the southeast- then bird exclosures would have been easier to construct ern coastal plain are receiving attention (C. Hunter, to preclude cormorant and heron damage. This informa- USFWS, personal communication). tion could have been provided by a professional who is • Criteria should be developed for reaching resource goals knowledgeable about waterbird biology. for JVs. Are population goals feasible to set? Are habitat area goals sufficient? How are quality criteria set? • Inventories should be supported to determine waterbird Acknowledgments ______status in critical wetlands, especially for little-studied species. Concentration hotspots for colonial waterbirds We thank Marcia Wilson and Bentley Wigley for advice in or rails could result in designations similar to those the development of this paper. Useful comments were provided used by WHSRN (i.e., sites of international, hemi- by M. Haramis, D. Pashley, M. C. Perry, and D. Sparling. spheric importance).

USDA Forest Service Proceedings RMRS-P-16. 2000 87