Species Groups of Special Interest
There are 32 native species of waterfowl that regularly use the estuarine, riverine, lacustrine, and palustrine wetlands and adjacent uplands in the New York Bight watershed as breeding, migrating, or overwintering birds (Table 2). This does not include pelagic birds and sea ducks that, within the watershed study area, are found exclusively in the marine waters of the New York Bight (discussed in seabirds chapter).
Although 12 species of waterfowl nest and breed in the New York Bight watershed, of which mallard (Anas platyrhynchos), American black duck (Anas rubripes), and Canada goose (Branta canadensis) are the most prevalent, the primary use of the New York Bight region by waterfowl is for resting and feeding during fall migration (peaking in November) and as a wintering area. In transit from the major breeding grounds in the Midwest, Canadian prairies, and Arctic to their wintering grounds along the Atlantic coast, several species of waterfowl migrate in fairly substantial numbers down the Hudson and/or along the Atlantic coast, stopping to rest and feed in the New York Bight watershed. For several species of waterfowl, the mid-winter populations occurring in the New York Bight account for a major part of their total Atlantic flyway population. Four of these species are discussed in more detail below.
The destruction of essential wetland habitats needed for breeding, migrating, and wintering has been identified as the principal reason for the drastic decline of waterfowl in the 20th century; to a lesser extent, over harvest has contributed to the decline of several species in North America. Contaminants, oil and chemical spills, lead poisoning, predation, and disease are other factors affecting the survival of waterfowl populations in this area. In the New York Bight, continued efforts to protect and enhance marshes, shallow bays, and adjacent upland areas will be critical for stabilizing and increasing waterfowl populations. Improving water quality in coastal bays will increase the availability of both plant and animal food items, and reducing contaminants will increase reproductive and survival rates.
In 1986, the North American Waterfowl Management Plan was signed by the United States and Canada; the plan was updated in 1989 to add Mexico as a full partner. This plan was created to reverse the decline in certain populations of ducks and geese. The plan establishes specific objectives to restore duck populations to the levels of the 1970s and targets critical waterfowl breeding, staging, and wintering areas in all three countries. The goal of the Atlantic Coast Joint Venture, one of nine joint venture areas in the United States, is to "protect and manage priority wetland habitats for migration, wintering, and production of waterfowl, with special consideration to black ducks, and to benefit other wildlife in the joint venture area." The specific objectives are to protect, manage, and enhance 355,787 hectares (879,138 acres) of wetland and upland buffer areas, and to improve and enhance an additional 67,171 hectares (165,977 acres) of federal and state wetland habitats currently managed for waterfowl within the Atlantic Coast Joint Venture Area, to maximize carrying capacity for waterfowl and other wildlife. The joint venture calls for the protection of 27,278 hectares (67,405 acres) in the Hudson River and New Jersey coastal marshes and the enhancement of 4,856 hectares (12,000 acres) along the Hudson River and south shore of Long Island.
Brant (Branta bernicla)
Brant, perhaps the northernmost-breeding bird in the world, nest on the coastal tundra in the far northern regions of North America, migrate south during the fall to a staging area in James Bay, Ontario, and proceed overland to New York Harbor where they disperse to their major wintering grounds along the coastal bays of Long Island and New Jersey. The wintering range of brant extends from Massachusetts south to South Carolina, but the majority (about 80%) of the wintering population occurs in the backbarrier lagoons of New Jersey and Long Island (Figure 5). The most important wintering sites appear to be the salt marsh-dominated bays from Great Bay south to Cape May in New Jersey and the Hempstead Bays on Long Island. Historically, wintering brant fed mainly on eelgrass (Zostera marina), but with a decline in eelgrass due to wasting disease and eutrophication of coastal bays, sea lettuce (Ulva lactuca) has become the primary food item, along with lesser amounts of eelgrass, widgeon grass (Ruppia maritima), and cordgrasses (Spartina spp.).
Greater scaup (Aythya marila)
Greater scaup breed in the Arctic and sub-Arctic from Hudson Bay west to Alaska, and migrate from northwestern Canada and Alaska across the continent to their wintering grounds along the Atlantic coast between Cape Cod and Chesapeake Bay. Greater and lesser scaup are not readily differentiated on aerial surveys, although ground counts, band recovery data, and hunters' bags reveal both that the majority of scaup in the New York Bight are greater scaup and that these birds represent a significant proportion, probably about 25%, of the total flyway population. Within the study area, the most important wintering area is the Raritan Bay - Sandy Hook Bay area (Figure 5). The adjacent waters of Long Island Sound are also an important wintering area. Greater scaup feed primarily on benthic invertebrates such as clams, mussels, and snails. These food preferences may make scaup more susceptible to bioaccumulation of contaminants in polluted areas. Analyses of scaup kidneys and livers from Long Island Sound have revealed that tissue levels of chlorinated hydrocarbons and heavy metals increased during the winter, and that levels of cadmium, selenium, and PCBs were at levels known to adversely affect reproduction in ducks. Midwinter inventory data show significant long-term declines in scaup, and the declines in greater scaup may be even more pronounced.
American black duck (Anas rubripes)
American black duck are restricted geographically to eastern North America, with the highest breeding densities occurring in coastal marshes, especially those of the eastern shore of Chesapeake Bay. Black ducks move south as northern marshes freeze over, and the most important migration corridor is along the Atlantic coast. The Virginian Province (Cape Cod, Massachusetts, to Cape Hatteras, North Carolina) contains the majority of black duck wintering habitat, and the New York Bight watershed is at the center of both the breeding and wintering ranges for black duck. About one-third of the total Atlantic flyway population winters in the New York Bight. Wintering black ducks are found, along with mallards, distributed in bays, marshes, and flats along the Hudson River, New York Harbor, and in the backbarrier lagoons of Long Island and New Jersey. The highest numbers are found in the Brigantine Unit of the Forsythe National Wildlife Refuge in New Jersey and in the Atlantic coast and Delaware Bay marshes of Cape May (Figure 5). Black ducks feed on a variety of plant and animal food items; in the winter, animal foods, including snails and mussels, become increasingly important. American black duck populations have declined dramatically over the past 40 years due to a combination of factors including habitat loss, over harvest, and competition and hybridization with mallards. The black duck was identified by the North American Waterfowl Management plan as a species of immediate international concern.
Bufflehead (Bucephala albeola)
Bufflehead breed primarily in northwestern North America and winter on both coasts. On the Atlantic coast they winter from Newfoundland to Florida, with concentrations in Maine and between Cape Cod and North Carolina. The New York Bight accounts for about one-quarter of the Atlantic flyway wintering population. Bufflehead feed on a variety of food items, and in northern estuaries the primary winter foods are crustaceans such as isopods, amphipods, and shrimp, mollusks, some fish, pondweeds, and widgeon grass. Bufflehead are distributed in small flocks throughout the backbarrier lagoons of the New York Bight along the New Jersey and Long Island coasts, with significant concentration areas in Barnegat Bay and the Cape May Atlantic coast marshes (Figure 5).
The Atlantic Flyway hosts two distinct populations of Canada goose, resident and migratory, during the winter. During the 1960s and 1970s, non-migrating Canada geese were relocated from the Midwest to many areas throughout the eastern United States where non-migrating populations had once existed but were extirpated by human development. These non-migrating birds settled onto golf courses, urban parks, and other protected areas and this resident population has exploded to the point that the birds are a nuisance in many areas. At the same time, the migratory populations of Canada goose which nest on the Ungava Peninsula in northern Quebec have declined dramatically (about 75%) since 1988. The large numbers of resident birds mask the decline in the migrant population. Until the migratory populations increase, hunting seasons have been and should continue to be limited to September before the migratory geese arrive and late January and February after they leave.
References:
Bellrose, F.C. 1980. Ducks, geese, and swans of North America, third edition. A Wildlife Management Institute book sponsored jointly with the Illinois Natural History Survey. Stackpole Books, Harrisburg, PA.
Kramer, G. 1994. Sea goose elusive. Birder's World, June 1994.
North American Waterfowl Management Plan. 1994. 1994 update to the North American waterfowl management plan: expanding the commitment.
U.S. Fish and Wildlife Service. 1973-1995. Mid-winter waterfowl survey - Atlantic Flyway data. Office of Migratory Bird Management, Laurel, MD.
U.S. Department of the Interior and Environment Canada. 1986. North American waterfowl management plan. A strategy for cooperation.
U.S. Fish and Wildlife Service. Undated. North American waterfowl management plan Atlantic coast joint venture.
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Colonial nesting marine birds and wading birds (waterbirds) are important and conspicuous components of coastal ecosystems in the United States. They represent several orders of waterbirds that share in common the trait of typically nesting in colonies, which most likely evolved as a defense against predators. There are 23 species of colonial waterbirds nesting in the New York Bight watershed. Two species, the great blue heron (Ardea herodias) and the green-backed heron (Butorides striatus), which often nest singly, mainly in interior wetlands, are not considered here; the majority of nesting by the other species is concentrated along the coast. Also considered as part of this group are two species of shorebirds, the piping plover (Charadrius melodus) and the American oystercatcher (Haematopus palliatus), which generally do not nest in distinct colonies, but do share the same habitats as many of the colonial nesters and are species of concern in the region.
New York State has surveyed colonial waterbirds on Long Island using ground counts annually since 1985. Before that, in the 1970s, aerial surveys of the Long Island colonies were conducted. The state of New Jersey surveys colonial waterbirds by helicopter about every five years, with the most recent surveys in 1985, 1989, and 1995. Both states survey certain beach-nesting birds (piping plover and least tern) annually. Federal coastal waterbird atlases were published for the Atlantic coast of the northeastern United States (Maine to Virginia) for 1977 and 1984-1985, and an atlas is now being compiled for 1994-1996. A summary of the estimated number of nesting pairs and number of colonies of waterbirds along the New York Bight coastline, including both New York and New Jersey, for 1985, 1989, and 1995 was compiled from the state surveys and is presented in Table 3.
The bays and islands of the New York Bight are extremely important for nesting and foraging by long-legged waders (herons, egrets, and ibises), with a total of over 7,500 pairs recorded in the most recent (1995) surveys. In 1985, a similar number of waders in the Bight accounted for about 23% of the total Atlantic coast population from Maine to Virginia. Glossy ibis (Plegadis falcinellus), snowy egret (Egretta thula), and black-crowned night-heron (Nycticorax nycticorax) are the most common species of long-legged waders nesting in the Bight. These birds prefer to nest in large colonies in shrubs or trees on salt marsh, dredged material, or rocky islands. They are thus most common where there is a prevalence of vegetated islands, especially the salt marsh and dredged material islands in the sounds and bays of southern New Jersey (Cape May, Great Egg Harbor, and Brigantine Bay and Marsh Complex) and western Long Island (Hempstead Bays and South Oyster Bay) and in the islands in New York - New Jersey Harbor (Arthur Kill Complex and North and South Brother Islands in the Narrows) (Figure 6). Smaller heronries also occur along the south shore bays of central and eastern Long Island (Great South Bay, Moriches Bay, and Shinnecock Bay) and in the northern coastal New Jersey bays (Great Bay and Barnegat Bay). In areas with numerous islands, the locations of heronries may shift significantly from year to year and from island to island, while there is higher site fidelity and long-term occupation in areas where there are only a few islands available for nesting. Populations of long-legged waders have been fairly stable over the past two decades, although recent declines in snowy egret (50% decline since 1989) and cattle egret (Bubulcus ibis) (70% decline since 1989) are of concern. For both of these species, especially the cattle egret, most of these declines have occurred in the Arthur Kill colonies, one of the largest colonies in the region. Double-crested cormorants (Phalacrocorax auritus) have recovered from earlier declines attributed to DDT and other pesticides and are expanding their range from the north into the Bight, occupying habitat similar to that of herons and in some instances displacing them.
The colonies of gulls and terns in the New York Bight are a significant component of the total Atlantic coast population. For example, in 1985 the New York Bight colonies of gulls and terns (excluding least tern (Sterna antillarum)) accounted for about 40% of the Atlantic coast population from Maine to Virginia. During this same period, for the common tern (Sterna hirundo) alone, the 1985 population in the Bight accounted for over 73% of the total Atlantic coast population. Gulls and terns nest on sparsely vegetated dredged material islands, rocky islands, dunes, beaches, and salt marsh islands and are widely distributed throughout the backbarrier lagoon system along the Atlantic shoreline of New Jersey and Long Island. Herring gull (Larus argentatus), for example, occurred at 146 different colonies in the Bight in 1995. As with the heronries, there is a great deal of year-to-year variability in the location of gull and tern colonies. Although some gull and tern species nest near their primary foraging areas, roseate terns (Sterna dougalli) are known to travel sizable distances from their nesting areas to foraging areas, e.g., over twelve miles in Long Island Sound. American oystercatcher and black skimmer (Rhynchops niger) nest in habitats similar to those of the gulls and terns, especially on sandy islands and shorelines. Populations of all three species of gulls, as well as two species of terns (common and roseate), have declined since 1989. There were about 79,000 pairs of gulls and terns recorded in the New York Bight in 1995, significantly fewer than in 1985 (118,000) or 1989 (132,000). The most significant decline has been in common tern, which has declined 72% since 1989. This regional decline is due in part to substantial declines at some of the larger colonies such as Cedar Beach (Jones Beach Island East) on Long Island, but declines have also occurred at smaller colonies throughout the region.
In contrast to the clumped distribution of gulls, terns, and long-legged waders, beach-nesting birds are more evenly dispersed along the ocean shorelines of Long Island and New Jersey. The largest numbers of piping plover (Charadrius melodus), least tern (Sterna antillarum), and black skimmer nest on sand barrier beaches and spits near inlets. The sand spits extending into Lower New York Bay from Long Island (Breezy Point) and New Jersey (Sandy Hook) have supported some of the highest nesting concentrations for piping plover in the region. Other important nesting beaches for piping plover include Jones Beach Island West (Hempstead Bays), Jones Beach Island East (Great South Bay), and Westhampton Beach (Moriches Bay) on Long Island, and Holgate (Barnegat Bay), Little Beach Island (Brigantine Bay and Marsh Complex), and Cape May Meadows (Cape May) in New Jersey. Populations of beach-nesting birds, formerly greatly reduced due to coastal development, recreation, market-hunting, and predation, have increased over the last decade, partly in response to greatly increased management and protection, e.g., signs, fencing, predator exclosures, and patrols, of nesting beaches. Overall productivity of beach nesting birds, however, remains low due to predation and other factors. The beaches of the New York Bight supported about a quarter of the total United States Atlantic coast population of piping plover in 1995, and in 1985 the least tern population was also about a quarter of the total coastal population from Maine to Virginia.
The extensive recreational, commercial, and industrial development along the U.S. coast, with concomitant habitat modification and impacts from oil and chemical spills, dredging operations, water pollution, human disturbances, and predation, have placed waterbird colonies at increasing risk to their survival, especially in the Northeast. The most significant threats to colonial nesting waterbirds in the New York Bight include human disturbance, predation, habitat degradation, and contaminants. Recreational use of bird-nesting islands and beaches during spring and summer breeding season is detrimental to disturbance-sensitive species such as plovers, terns, and wading birds. Nesting populations of colonial waterbirds and piping plovers on sand or gravel beaches in this area are especially vulnerable during the nesting season (April to August) to human-caused disturbances such as trampling or destruction of nests from beach-walking, picnicking, boat landings, off-road vehicle use, and disturbance by pets. Predation is a major problem in waterbird colonies in the New York Bight. On beaches, mammalian predators such as foxes, skunks, raccoons, rats, dogs, and cats are a major problem; islands, although generally free from mammalian predation, may be subject to predation by gulls, crows, other birds, and insects. Degradation of nesting and foraging habitat is a major threat to both island-nesting and beach-nesting species. Attempts to stabilize and control erosion on beaches often result in a loss of natural diversity of beaches and decreased habitat suitability for nesting and feeding plovers. Increased vegetation and succession on some islands may reduce their suitability for nesting by terns and gulls. Destruction of trees from the guano of nesting and perching double-crested cormorants has reduced the suitability of many nesting islands for herons in Long Island Sound and may affect additional areas as cormorants expand to the south. Competition for nesting sites and predation by gulls results in loss of tern nesting habitat. Contaminants continue to be a major threat to waterbirds, especially those that feed at or near the top of the aquatic food chain where organochlorine pesticides and other contaminants can accumulate at high levels. Of special concern are the heronries in the Arthur Kill in New York Harbor, which occur near sites heavily contaminated by dioxin, heavy metals, and other chemicals.
Attempts should be made to eliminate all human-related disturbances to bird-nesting colonies during the critical nesting season by all available means, including posting, fencing, boat warden patrols, and public education. Further, there is a need for active habitat management and vegetation control to enhance conditions favorable to breeding bird colonies and to discourage the proliferation of gulls, other human-associated species, and natural predators. Dredged material deposition should be designed to enhance habitat on nesting islands and beaches or even to create offshore islands. Erosion control projects should be done in a way that recognizes the dynamic nature of barrier islands and natural processes such as overwash and breaching, as well as the needs of the natural communities and of fish and wildlife species that occur in the nearshore waters, on the beach and dunes, and in the backbarrier bays and marshes. Acute and chronic impacts of contaminants on colonial nesting waterbirds and their forage base require additional study, and contaminated sites that are foraging areas for waterbirds should be given a high priority for remediation. Regional declines in populations of waterbirds such as the above-noted decline in common tern should be investigated further to determine if the declines are part of natural fluctuations or whether they are related to contaminants or other threats. While the emphasis for protecting waterbirds has typically been on nesting sites, it is extremely important to better understand and protect important foraging and stopover areas as well. Because of the high turnover rate in waterbird colonies, all potential and alternate colony sites in appropriate habitat, as well as existing colonies, should be managed and protected.
References:
Andrews, R. 1990. Coastal waterbird colonies: Maine to Virginia, 1984-1985. An update of an atlas based on 1977 data, showing colony locations and species composition at both time periods, with examination of changes in regional populations. U.S. Fish and Wildlife Service, Newton Corner, MA.
Buckley, P.A. and F.G. Buckley. 1980. Population and colony-site trends of Long Island waterbirds for five years in the mid-1970s. Transactions of the Linnaean Society of New York 9:23-56.
Erwin, R.M. and C.E. Korschgen. 1979. Coastal waterbird colonies: Maine to Virginia, 1977. An atlas showing colony locations and species composition. U.S. Fish and Wildlife Service, Biological Services Program, FWS/085-79/08.
Jenkins, C.D., Jr., L.J. Niles, and J. Wessel. 1990. Survey of colonial nesting waterbirds on the Atlantic Coast of New Jersey - 1989. New Jersey State Department of Environmental Protection, Division of Fish, Game and Wildlife, Endangered and Nongame Species Program, Trenton, NJ.
Howe, M.A., R.B. Clapp, and J.S. Weske. 1978. Marine and coastal birds. Marine Ecosystems Analysis Program New York Bight Atlas Monograph 31. New York Sea Grant Institute, Albany, NY.
Litwin, T.S., A. Ducey-Ortiz, R.A. Lent, and C.Liebelt. 1993. 1990-1991 Long Island colonial waterbird and piping plover survey. Conducted by New York State Department of Environmental Conservation in cooperation with the Seatuck Research Program.
New Jersey State Department of Environmental Protection. 1996. Unpublished 1995 colonial waterbird survey data. Endangered and Nongame Species Program, Trenton, NJ.
New York State Department of Environmental Conservation. 1996. 1995 Long Island colonial waterbird and piping plover survey. Division of Fish and Wildlife, Region 1, Stony Brook, NY.
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Seabirds are those birds that spend most of their lives on the open waters of the ocean, coming to land only to breed. This group is composed of members of several different bird families, and may be broadly lumped into two subgroups based on distribution: a coastal or nearshore group that is most common within about three miles of land and includes the sea ducks, loons, grebes, and gulls; and a pelagic or oceanic group (pelagic birds) that generally occurs farther offshore, out of sight of land, and includes shearwaters, petrels, fulmars, gannetts, phalaropes, skuas, kittiwakes, jaegers, and auks. Other waterbirds such as terns and cormorants that are associated with the sea, but that occur primarily in bays and on land during the non-breeding period, are not included here but are discussed in the colonial waterbird chapter and individual habitat narratives. Also, species that are only occasionally sighted in the New York Bight, such as common murre (Uria aalge) and long-tailed jaeger (Sterocorius longicaudus), are not included here. Major groups of seabirds that regularly occur in the New York Bight are briefly described below and listed in Table 4 along with their seasonal use, distribution, and relative abundance in the Bight.
Seasonal Distribution Patterns in the New York Bight
Seabirds are not evenly distributed in space or time in the New York Bight. Concentration areas, species composition, and densities of non-breeding birds shift seasonally, depending upon the distribution of migration habitats and food resources. Figure 7 shows the density of pelagic birds observed by season in the New York Bight based on 1980-1988 data from the National Marine Fisheries Service systematic seabird survey database.
In the summer, when many species of seabirds are on their breeding grounds outside of the Bight, relatively low densities and species diversity of seabirds are observed in the Bight. Concentrations of birds do occur in the vicinity of the Hudson Shelf valley and Hudson Canyon, off the south shore of Long Island, and south and east of Montauk Point. These distributions may be related to the outflow of nutrient-rich waters and associated coastal fish and invertebrates, a primary food resource for these bird species, from the Hudson-Raritan Estuary, Long Island Sound, and the coastal bays. In summer, shearwaters and storm-petrels are the most abundant pelagic birds in the New York Bight. In general, petrels and shearwaters are abundant and widely distributed globally and, in fact, shearwaters are probably the most abundant group of birds in the world. The greater shearwater (Puffinus gravis), sooty shearwater (Puffinus griseus), and Wilson's storm-petrel (Oceanites oceanicus) breed in the southern hemisphere and spend much of their non-breeding period in the North Atlantic, including the New York Bight. Cory's shearwater (Calonectris diomedea) breeds in the eastern North Atlantic and Mediterranean and ranges west to the Atlantic coast of North America during the summer and fall. The Manx shearwater (Puffinus puffinus) and Leach's storm-petrel (Oceanodrama leucorhoa) breed in the North Atlantic (including some breeding records from the Elizabeth Islands in Massachusetts) and migrate through the New York Bight in the summer and fall. Gulls and terns that are nesting on the beaches and islands in the New York Bight feed on fish and marine invertebrates in the nearshore waters of the New York Bight and its bays and estuaries.
In the fall, the highest densities of seabirds are observed south and east of Montauk Point, along the south coast of Long Island, in the Apex of the Bight, and off the mouth of Delaware Bay. As in the summer, this distribution may be related to the food base provided by these productive bays and estuaries. The most common pelagic birds migrating through the New York Bight in the fall and spring include shearwaters, petrels, gannetts, phalaropes, and jaegers. Substantial numbers of waterfowl, especially sea ducks, and waterbirds also move into and migrate through the Bight in the fall. Two species of jaegers, pomarine (Stercorararius pomarinus) and parasitic (Stercorararius parasiticus), breed in the North Atlantic and are present in low numbers in the New York Bight in the spring and fall. The northern fulmar (Fulmaris glacialis) breeds in the Arctic and occurs in the Bight during its non-breeding period, including the fall and winter, although it is most common in the Bight in the spring. Two species of phalarope, red phalarope (Phalaropus fulicaria) and red-necked phalarope (Phalaropus lobatus), breed in the Arctic, winter in the tropics, and migrate through the offshore waters of the New York Bight in the spring and fall, feeding on crustaceans and other marine invertebrates. The northern gannett (Sula bassanus) breeds north of the New York Bight and migrates through the Bight in substantial numbers. The migration of seabirds along the coastline of the New York Bight in the fall appears to be quite significant. A seabird survey in Avalon, New Jersey (Avalon Sea Watch) counted almost 900,000 birds migrating past one point on the New Jersey shoreline in 1995 during the late summer and fall, including nearly 50,000 red-throated loons (Gavia stellata), over 46,000 gannetts, over 200,000 double-crested cormorants (Phalacrocorax auritus), and over 440,000 scoters (Melanitta spp.).
In the winter, moderate densities of birds are observed dispersed over the entire continental shelf. Concentrations of birds occur at similar locations as in the fall, with higher concentrations off Delaware Bay and also along the shelf edge near Baltimore and Wilmington Canyons. During the winter, kittiwakes, skuas, gannetts, and auks occur in the offshore waters of the New York Bight, while coastal waters are dominated by gulls, sea ducks, loons, and grebes. The black-legged kittiwake (Rissa tridactyla) breeds in the Arctic and is one of the more common pelagic birds in the open waters of the New York Bight during the fall, winter, and spring. Great skua (Catharacta skua) breeds and winters in the North Atlantic and regularly occurs well offshore during the winter in the New York Bight. Three species of alcids (auks) are regularly observed at low densities in the Bight during the winter, razorbill (Alca torda), dovekie (Alle alle), and thick-billed murre (Uria lomvia). These small, duck-like birds are found primarily in offshore waters where they feed on fish and crustaceans. Two species of loons, common loon (Gavia immer) and red-throated loon, migrate through and winter in the New York Bight. These birds winter in both the pelagic and coastal zones of the Bight and also occur in coastal bays. Loons feed primarily on fish, but also feed on crustaceans, insects, and mollusks. Two species of grebes, horned grebe (Podiceps auritus) and red-necked grebe (Podiceps grisegena), also frequent the nearshore waters and coastal bays. Sea ducks, including black, white-winged, and surf scoters (Melanitta nigra, M. fusca, and M. perspicillata) and oldsquaw (Clangula hyemalis), are widely distributed in low numbers in the coastal waters of the New York Bight. Common eider (Somateria mollissima), king eider (Somateria spectabilis), and harlequin duck (Histrionicus histrionicus) primarily winter off rocky coasts to the north of the New York Bight, but the common eider appears to be expanding its wintering range to the south into the Bight, and harlequins and king eiders regularly occur off Montauk Point. Two species of gulls that breed in the New York Bight watershed, the herring gull (Larus argentatus) and greater black-backed gull (Larus marinus), are abundant in winter in the bays, coastal waters, and offshore waters of the New York Bight.
The highest densities of seabirds in the New York Bight occur in the spring on the outer continental shelf near the shelf break, particularly in the vicinity of Block Canyon. During the late winter and spring, the waters are well-mixed and fish and invertebrates associated with the upwelling of nutrient-rich waters along the shelf break provide an abundant food source for pelagic birds. Pelagic birds migrating through and moving into the New York Bight in the spring include many of the same species that migrate through in the fall, including shearwaters and petrels, fulmars, skuas, gannetts, phalaropes, and jaegers.
It is important to note that published survey data to date are not extensive, regular, or systematic enough to fully describe the use of the New York Bight by pelagic birds. Only species composition, range, and selected high-use areas are known. Surveys of the Bight do indicate the importance of this area for a variety of pelagic and coastal birds, however. A better understanding of the seasonal distribution of pelagic birds in the New York Bight is needed in order to better respond to oil spills and to provide direct conservation efforts and benefits to this important group of birds. The Avalon Sea Watch indicates the importance of the New York Bight coastline as a migration route; it would be helpful to have additional sea watch stations, such as one at Sandy Hook and at Montauk Point, to better track migrations. It would also be useful to have nighttime studies to determine where the large flocks of birds that migrate during the day congregate at night.
Threats and Conservation Considerations
Major threats to pelagic birds in the New York Bight include oil spills and impacts to water quality in the Bight proper and adjacent estuaries, or other factors that affect their food base, such as over harvesting of fish. There is a great deal of tanker traffic in the New York Bight and the practice of lightering (transferring oil from large tankers to smaller ships) in the Bight outside of the New York - New Jersey Harbor increases the risk of a spill. An oil spill in the New York Bight would have both direct and indirect impacts on all species of seabirds. Researchers have attempted to assess the relative risk of oil spills to marine and coastal bird species in regions of the North Atlantic and have developed an bird oiling index based on behavior, population size, and distribution. Index numbers for the Mid-Atlantic Bight (Cape Cod to Virginia) are indicated in Table 4; higher index numbers indicate greater vulnerability to oil spills (this index is fully described in Hoopes et. al 1994). Other activities on the continental shelf, such as ocean dumping and sand mining, could directly or indirectly impact pelagic birds. Impacts to the coastal fisheries populations from pollution, over harvest, and other factors in the coastal bays and estuaries of the New York Bight will also affect those pelagic and coastal birds that depend upon these fish and invertebrates for food.
References:
Cape May Bird Observatory. 1995. Avalon sea watch data for 1995. Unpublished data.
Center for Natural Areas. 1977. A summary and analysis of environmental information on the continental shelf from the Bay of Fundy to Cape Hatteras. Vol. 1, bk. 3: xv. Prepared for the Bureau of Land Management by the Center for Natural Areas, S. Gardiner, ME.
Howe, M.A., R.B. Clapp, and J.S. Weske. 1978. Marine and coastal birds. Marine Ecosystems Analysis Program, New York Bight Atlas Monograph 31. New York Sea Grant Institute, Albany, NY.
Leck, C.F. 1985. Pelagics off New Jersey. New Jersey Audubon Society Records of New Jersey Birds 11(1):2-4.
Murphy, R.C. 1967. Distribution of North Atlantic pelagic birds. Serial Atlas of the Marine Environment, folio 14. American Geographical Society.
Hoopes, E.M., P.M. Cavanagh, C.R. Griffin, and J.T. Finn. 1994. Synthesis of information on marine and coastal birds of the Atlantic coast: abundance, distribution, and potential risks from oil and gas activities, 3 vols. Prepared by Massachusetts Cooperative Fish and Wildlife Research Unit, University of Massachusetts, Amherst, MA. Prepared for U.S. Department of the Interior, Minerals Management Service, Herndon, VA.
Powers, K.P. 1983. Pelagic distribution of marine birds off the northeastern United States. National Oceanic and Atmospheric Administration Technical Memorandum NMFS-F/NEC-27. U.S. Department of Commerce, National Marine Fisheries Service, Woods Hole, MA. 201 p.
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There are 30 species of migratory shorebirds, plovers, sandpipers, avocets, and oystercatchers, that regularly use marine and freshwater habitats and adjacent uplands in the New York Bight watershed for breeding, wintering, northward (spring) migration, or southward (autumn) migration (Table 5). Most of these species of shorebirds breed in interior regions of North America, especially in the Arctic and subarctic, and spend two-thirds to three-quarters of the year on migration routes and wintering grounds. Seven shorebird species nest within the New York Bight watershed, including beach-nesting shorebirds (discussed under the colonial waterbird chapter) and grassland-nesting species (discussed under the Neotropical migrant chapter). Shorebirds show a strong affinity for wetlands, and typically swarm the beaches, marshes, and tidal flats during migration. Large numbers of migratory shorebirds travel great distances between breeding and wintering grounds and concentrate in small stopover areas with seasonally-abundant food resources to accumulate energy reserves for continuing their long-distance flights. Because large numbers of shorebirds are concentrated in just a few areas during migration, loss or degradation of key sites could devastate these populations. Analyses of the International Shorebird Survey (ISS) data(1) have indicated recent declines in several species of shorebirds, including black-bellied plover (Pluvialis squatarola), whimbrel (Numenius phaeopus), red knot (Calidris canutus), sanderling (Calidris alba), semipalmated sandpiper (Calidris pusilla), least sandpiper (Calidris minutilla), and short-billed dowitcher (Limnodromus griseus); counts at Delaware Bay have also documented regional declines in sanderling and semipalmated sandpiper.
1The International Shorebird Survey is a volunteer shorebird survey at over 600 sites in the United States coordinated by the Manomet Center for Conservation Sciences. Cooperators census shorebirds three times monthly during key migration periods at a site selected by the cooperator. There are 28 survey sites within the New York Bight study area, mostly concentrated in the backbarrier lagoons along the New Jersey and Atlantic coasts (see Figure 8).
Shorebirds migrate through the New York Bight almost all year round, with northward migration beginning in late winter and lasting through June, and southward migration beginning in late June with peaks in late July and lasting into the fall. Shorebirds rely on a mosaic of shallow coastal or freshwater wetlands and adjacent upland areas. Foraging habitats include beaches, mudflats, sandflats, salt marshes, impoundments, flooded agricultural fields, and grasslands. In coastal areas, preferred food items include macroinvertebrates such as polychaete worms, crustaceans, mollusks, or insects. Roosting habitats, usually used at night or during high tide periods when primary feeding areas are not accessible, include salt marshes, sandflats and beaches above the tide line, and sparsely vegetated islands free of predators. Although migrating shorebirds occur throughout the shallow bays and estuaries of the New York Bight, especially during the autumn migration, there are relatively few sites that consistently support large numbers of shorebirds. Analyses of ISS data, Christmas bird counts, and migration season accounts from American Birds for the Western Hemisphere Shorebird Reserve Network (WHSRN) identified seven sites with counts of 5,000 or more shorebirds partially or wholly within the New York Bight watershed during spring, autumn, or winter. These sites, from south to north, include Delaware Bay (spring migration), Cape May (wintering), Great Egg Harbor (autumn and spring migrations), Brigantine Beach (autumn migration), Brigantine (E.B. Forsythe) National Wildlife Refuge/Oceanville (autumn migration and wintering), Jamaica Bay (autumn and spring migrations), and Hackensack Meadowlands (autumn migration) (Figure 8). Delaware Bay has been designated as a hemispherically important site under WHSRN. There are also important shorebird concentration areas along the south shore of Long Island and other bays in New Jersey that appear to be under-represented in the ISS database and may have similar levels of shorebird use. Since these surveys are not systematic, it is very likely that the shorebird use in the New York Bight is underestimated and that additional sites of regional or national importance to shorebirds are yet to be identified.
The shoreline of Delaware Bay, including the Cape May shoreline, is a critical spring migration stopover for shorebirds, with peak single-day counts of 200,000 to 400,000 birds and estimated totals of 800,000 to 1.5 million shorebirds passing through Delaware Bay each spring. Delaware Bay is the largest spring shorebird staging area on the east coast of the United States, and one of the top ten sites in the Western Hemisphere. Six species make up 95% of the birds staging in Delaware Bay in the spring: semipalmated sandpiper, red knot, ruddy turnstone (Arenaria interpres), and sanderling, with lesser numbers of dunlin (Calidris alpina) and short-billed dowitcher. The peak stopover is synchronized with the availability of horseshoe crab eggs along the Delaware Bay shoreline; the bay is reported to contain the largest concentration of horseshoe crab eggs in the eastern United States. Shorebirds are dependent on the variety of estuarine habitats on both the Delaware Bay and Atlantic coast sides of the Cape May Peninsula (for additional detail, see narrative for Cape May Peninsula).
The greatest threats to migrating shorebirds in the New York Bight are loss and degradation of coastal habitats and human disturbance. Protection efforts for shorebirds should focus on preserving and protecting key foraging and roosting habitats, reducing disturbance, and enhancing and restoring wetland and adjacent upland habitats. Remaining coastal areas with high densities of shorebirds during migration periods need to be protected from further development or degradation through acquisition, easements, or other means. Disturbance of shorebirds at feeding and roosting sites should be minimized through posting, fencing, public education, and other means. At publicly owned sites, access to key feeding and roosting areas should be limited during migration periods. Migrating shorebirds are concentrated and particularly vulnerable at roosting sites during high tide. Improving and maintaining water quality in the coastal bays and estuaries of the New York Bight watershed should be a priority in order to maintain and improve the invertebrate food base upon which shorebirds depend. Key migration stopover sites are extremely vulnerable to oil and chemical spills and should have contingency plans and equipment in place in case a spill occurs. Coastal wetland habitats and adjacent upland habitats should be restored, enhanced, and managed for a diversity of wildlife, including shorebirds and waterfowl. Restoration and enhancement of high marsh habitat, especially salt pannes, would benefit shorebirds. Open marsh water management (OMWM) is a technique being employed to enhance salt marsh habitat through creation of ponds and channels; OMWM ponds should be constructed with shallow sloping shorelines and islands to benefit shorebirds. Management of impoundments should be planned and implemented to maximize both invertebrate availability for shorebirds and plant seed production for waterfowl. Upland areas should be managed to create short sparse vegetation for nesting and foraging shorebirds.
References:
Burger, J. 1984. Abiotic factors affecting migrant shorebirds. In J. Burger and B.L. Olla (eds.) Behavior of marine animals, vol. 6, shorebirds: migration and foraging behavior, pp. 1-72. Plenum Press, New York, NY.
Clark, K., L. Niles, and J. Burger. 1993. Abundance and distribution of shorebirds migrating on Delaware Bay, 1986-1992. The Condor 95:694-705.
Dunne, P., R. Kane, and P. Kerlinger. 1989. New Jersey at the crossroads of migration. New Jersey Audubon Society, Franklin Lakes, NJ. 74 p.
Harrington, B.A, J.P. Myers, and J.S. Grear. 1989. Coastal refueling sites for global bird migrants. Coastal Zone '89, Proceedings of the Symposium of Coastal and Ocean Management, pp. 4293-4307. American Society of Civil Engineers, New York, NY.
Harrington, B.A. and J.L. Lyons. 1990. On the importance of wildlife areas in the United States to shorebirds migrating east of the 105th longitude line. Draft report prepared for the National Fish and Wildlife Foundation, Washington, D.C. Manomet Bird Observatory, Manomet, MA.
Harrington, B. and E. Perry. 1995. Important shorebird staging sites meeting Western Hemisphere Shorebird Reserve Network criteria in the United States. Wildlife Habitat Canada and Western Hemisphere Shorebird Reserve Network, Manomet Observatory, Manomet, MA. Working draft.
Hayman, P., J. Marchant, and T. Prater. 1986. Shorebirds: an identification guide to the waders of the world. Houghton Mifflin, Boston, MA.
Helmers, D.L. 1992. Shorebird management manual. Western Hemisphere Shorebird Reserve Network. Manomet, MA. 58 p.
Howe, M.A., R.B. Clapp, and J.S. Weske. 1978. Marine and coastal birds. Marine Ecosystems Analysis Program New York Bight Atlas Monograph 31. New York Sea Grant Institute, Albany, NY.
Howe, M.A., P.H. Geissler, and B.A. Harrington. 1989. Population trends of North American shorebirds based on the International Shorebird Survey. Biological Conservation 49:185-199.
Niles, L.J., K. Clark, and S. Paul. 1994. Comprehensive management plan for shorebirds on Delaware Bay. New Jersey State Endangered and Nongame Species Program, Division of Fish, Game and Wildlife, Trenton, NJ.
Pfister, C. and B.A. Harrington. 1992. The impact of human disturbance on shorebirds at a migration staging area. Biological Conservation 60:115-126.
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The term Neotropical migrant refers to those migratory bird species that nest in North America north of the U.S.-Mexico border and Caribbean, and winter in the Neotropical region south of the continental United States. In recent decades, this group as a whole has undergone significant population declines, primarily due to loss or fragmentation of breeding habitat in the U.S. and Canada, resulting in smaller patches of available habitat, increased predation, and parasitism, or loss of wintering habitat in Mexico, the Caribbean, Central America, and South America, or a combination of factors. In eastern North America, where the best information is available, breeding surveys indicate that 44% of Neotropical migrant species have significantly declined either over the long term (1966-1988) or the short term (1978-1988), or both.
Of the 132 bird species listed as short-distance or long-distance migrants by Partners in Flight(2) that regularly breed in the northeastern United States, 115 breed in the New York Bight watershed. Table 6 includes a partial list of those species along with various ranking factors described below. The most common species, e.g., house wren, yellow warbler, whose populations are increasing are not included on this list. Several of the short-distance migrant species on the list that are at the northern end of their wintering range may also winter in the New York Bight (seasonal use column in Table 6). Efforts to set priorities for Neotropical migrant species in the northeast region of the United States have focused on both the population trends and the importance of the region to the species. There are 24 species of Neotropical migrants breeding in the New York Bight whose populations significantly declined from 1966-1990 in the Northeast, based on breeding bird survey data (significantly declining species are indicated by a 5 in the trend column in Table 6). Of these, 17 species (71%) are associated with successional habitats, i.e., grasslands, old fields, open woodlands, emergent or scrub-shrub wetlands, and 7 species (29%) are associated with mature forest. Part of this decline in successional species can be attributed to the reversion of farmlands and other successional habitat to mature forest in the Northeast. This group of 24 declining species should be given high priority for conservation efforts.
2Partners in Flight is a cooperative Neotropical bird conservation program among federal, state, international, and private organizations. Long distance migrants (List "A") are those that breed in North America and spend their non-breeding period primarily south of the United States. Short distance migrants (List "B") are those species that breed and winter extensively in North America, with a shift southwards in the winter season; however, some populations winter south of the United States.
The importance of the northeast region for specific nesting Neotropical migrants was assessed by researchers at Cornell University (Rosenberg and Wells 1995) by estimating the percent of each species' total population in the Northeast; this estimate was based on the percent of a species' total range that occurs in the Northeast and the abundance of that species within its range in the Northeast (see cited reference for detailed methodology). This information, along with the rank of the 34 species with greater than 15% percent of their total population in the Northeast, is included in Table 6. Species that nest in the Bight with the highest percentage (greater than 25%) of their total breeding population in the Northeast include, in declining order: Bicknell's thrush (Catharus bicknelii), scarlet tanager (Piranga olivacea), worm-eating warbler (Helmitheros vermivorous), Louisiana waterthrush (Seirus motacilla), wood thrush (Hylocichla mustelina), black-throated blue warbler (Dendroica caerulescens), blue-winged warbler (Vermivora pinus), gray catbird (Dumetella carolinensis), golden-winged warbler (Vermivora chrysoptera), eastern phoebe (Sayornis phoebe), Acadian flycatcher (Empidonax virescens), cerulean warbler (Dendroica cerulea), and Blackburnian warbler (Dendroica fusca). Those species that have the highest percentage of their range in the Northeast also tend to have small total ranges; they are the species for which long-term conservation efforts in the region may have the most beneficial impact, even though some of them are currently quite common in the region.
General patterns of distribution for Neotropical migrant breeding birds in the New York Bight roughly follow physiographic regions (Figure 3) based on the species' climatic and/or habitat affinities. Several species reach either their northern or southern range limits in the New York Bight watershed. Boreal species such as Bicknell's thrush, Swainson's thrush (Catharus ustulatus), blackpoll warbler (Dendroica striata), or yellow-bellied flycatcher (Epidonax alnorum) that nest primarily to the north of the New York Bight watershed occur only at high elevations in the Catskills within the study area. Another group of northern species occurs primarily in the higher elevation forests of the Allegheny Plateau (including the Catskills), Shawangunk - Kittatinny Ridge, New York - New Jersey Highlands, Taconic Mountains, and Rensselaer Hills, and are not generally found in the lower elevation valleys such as the Hudson and Wallkill River valleys. Examples of this latter group include black-throated green warbler (Dendroica virens), black-throated blue warbler (Dendroica caerulescens), blackburnian warbler (Dendroica fusca), and Canada warbler (Wilsonia canadensis). This distribution is in contrast to typically southern species such as worm-eating warbler and grassland species such as eastern meadowlark (Sturnella magna) that prefer the valleys and lowlands, but generally do not nest in the higher and cooler Allegheny Plateau or Highlands areas. Another group of species that is most common in the Coastal Plain include southern and midwestern species such as prothonary warbler (Protonotaria citrea) or blue grosbeak (Guiraca caerulea). Pine and prairie warblers (Dendroica pinus and D. discolor) are concentrated in the pine barrens on the Coastal Plain in New Jersey and Long Island. Other species such as wood thrush and scarlet tanager, two species experiencing significant declines in the region, are widely distributed in areas of mature deciduous forest, although nesting success may be low in smaller forest fragments.
Species that have both a high percentage of their total population in the Northeast and are undergoing population declines include Henslow's sparrow (Ammodramus henslowii), golden-winged warbler, worm-eating warbler, cerulean warbler, Louisiana waterthrush, whip-poor-will (Caprimulgus vociferus), and Canada warbler. These species should be accorded high priority for conservation in the watershed; several of these species are already listed as endangered or threatened by one or both states. Henslow's sparrow is extremely rare in the New York Bight watershed, occurring as a confirmed or probable breeder in only two breeding bird atlas blocks(3) in the Hudson and Wallkill Valleys and as a possible breeder in two atlas blocks in New Jersey. Henslow's sparrow occupies grasslands; its decline is due in part to loss or succession of its preferred habitats, former agricultural areas and wet meadow habitats. Golden-winged warbler prefer second-growth grassy and shrubby areas with a few trees, such as habitat that develops after farmland is initially abandoned. The distribution of this species in the watershed is patchy; concentration areas include the New York - New Jersey Highlands and the Wallkill Valley. Worm-eating warbler generally nest in deciduous woods in hilly areas, especially in or near wetlands or streams. Important concentrations of this bird occur in the New York - New Jersey Highlands, Manhattan Hills (outside of New York City), and the lower Hudson Valley. Cerulean warbler prefer to nest in the treetops of mature deciduous forests. Its limited distribution in the New York Bight watershed includes concentration areas in the New York - New Jersey Highlands and the Kittatinny Ridge. Louisiana waterthrush prefer medium to high gradient streams in forested areas and is commonly found in the Catskills, New York - New Jersey Highlands, Manhattan Hills (outside of New York City), Harlem Valley - Taconic Highlands, Hudson Valley, and Shawangunk - Kittatinny Ridge. Whip-poor-will prefer dry, open woodlands and is locally common in the Long Island Pine Barrens and New Jersey Pinelands. Canada warbler prefer cool, humid woodlands at higher elevations and in the New York Bight occur in the Allegheny Plateau, the New York - New Jersey Highlands, the Taconic Highlands, and the Rensselaer Hills.
3The Breeding Bird Atlas is a statewide effort to determine possible, probable, or confirmed breeding birds in small atlas blocks throughout the state; in New York 5 X 5 km blocks throughout the state were surveyed from 1980-1985 (Andrle and Carroll 1988) and in New Jersey similar sized blocks based on 1/6 of each 15' quadrangle are being surveyed from 1993-1996 (first two years analyzed for this report, New Jersey Audubon Society 1995).
Conservation efforts should focus on protecting fairly large and unfragmented habitat tracts, especially forested areas and grasslands, that contain substantial numbers of breeding pairs and/or a diversity of nesting Neotropical migrant species and that may serve also as migratory corridors and staging areas. Fragmentation of forested habitat has resulted in overall loss of habitat, an increase in edge habitat and associated edge effects, especially increased predation and nest parasitism, and isolation effects. Many species of forest-nesting birds appear to be area-sensitive, that is, species that tend to occur or achieve their highest densities only on large, unbroken tracts of forest. Examples of declining area-sensitive, forest-nesting birds in the New York Bight watershed include wood thrush, cerulean warbler, and black-and-white warbler (Mniotilta varia). Smaller fragments of forested habitat may act as sinks, or areas that are continually re-colonized from more productive areas or sources, but where, within these sinks, production is too low to sustain a population without outside recruitment. Conservation of these area-sensitive, forest-interior nesting birds in the New York Bight and elsewhere in the region depends on maintaining large areas of unfragmented forest. The majority of forest interior species need 150 hectares (370 acres) or more for successful breeding and as much as 3,000-hectare (7,400-acre) tracts may be needed to maintain viable breeding populations of all forest-nesting Neotropical migrant birds in the Northeast. Large areas of unfragmented forested habitat in the New York Bight occur primarily in the New York - New Jersey Highlands, Catskill High Peaks, Shawangunk - Kittatinny Ridge, and Taconic Mountains (Figure 9). Large forested areas should be preserved intact, edge habitat should be minimized, and forested connecting corridors should be maintained.
As noted above, bird species breeding in successional habitats have declined in the Northeast even more than have forest-nesting species. One group of declining successional nesting species of particular interest is grassland birds. Grassland-nesting and foraging Neotropical migrant birds in the New York Bight include upland sandpiper (Bartramia longicauda), short-eared owl (Asio flammeus), vesper sparrow (Pooecetes gramineus), grasshopper sparrow (Ammodramus savannarum), Henslow's sparrow, savannah sparrow (Passerculcus sandwichensis), bobolink (Dolichonyx oryzivorous), and eastern meadowlark. Relatively large grassland areas remaining in the New York Bight watershed include the southwestern portion of the New York - New Jersey Highlands, the adjacent upper Raritan River watershed, the Wallkill River valley, and parts of the lower Hudson Valley (Figure 10). These areas are or were formerly dominated by agricultural land use, especially pastures and hay fields, that historically supported grassland birds. Much of the remaining farmland has been converted from pasture to row crops or has grown up into young forested areas, and many of these areas are now under tremendous pressure for residential and commercial development. In urban and suburban areas, grasslands that are maintained as parts of parks, airports, or other facilities are becoming increasingly important to grassland bird species. Examples include Atlantic City Airport in the New Jersey Pinelands and Floyd Bennett Field in Jamaica Bay. Efforts to reverse the declining trend in grassland bird populations in the New York Bight should focus on farmland preservation and cooperative agreements that restore and manage open space as grasslands. In rural areas, agreements and incentives should be developed with farmers to plan timing and frequency of mowing, and to let fields remain fallow in order to benefit grassland birds. In urban/suburban areas, public and privately-owned sites such as airports, corporate parks, college campuses, landfills, and parks should be restored and/or managed as grasslands. It is important to distinguish between those areas where grasses are maintained solely to encourage and sustain grassland-breeding birds and those natural grassland ecosystems containing the full diversity of native grasses, plants, and wildlife. Restoration of native grass and forb species in these open space areas would benefit not only grassland birds, but also insects and other wildlife.
Although the focus of research and conservation efforts for Neotropical migrants has been on breeding and wintering grounds, habitat used during migration may be equally important to the survival of a species population. Migrating birds following "programmed" pathways must be able to satisfy energy requirements, avoid predators, and minimize environmental stress during stopovers. Important migration corridors and stopover habitat for Neotropical migrant landbirds in the New York Bight watershed include the Hudson River, the urban core of New York City, the north-south oriented ridges of the New York -New Jersey Highlands and the Shawangunk - Kittatinny Ridge, and the coastal corridor of barrier beaches, backbarrier lagoons, wetlands, and forests along the shorelines of Long Island and New Jersey. The importance of the New York Bight to migrating birds is exemplified at Cape May, New Jersey, at the southern tip of the study area where birds are funneled down to a single point by the coastline and prevailing winds. Millions of songbirds pass through Cape May each fall and 70,000 raptors on average are counted in the annual fall hawk watch. Raptors, especially accipiters, migrate along and feed in the barrier beaches and dunes of Long Island and New Jersey. Recent surveys of migrating birds in open space areas in the metropolitan New York City area have indicated high abundance and diversity of birds. A large number of migratory birds are funneled through the urban core by the orientation of the coastline and other geographic features of the area, and these birds are further concentrated in the small amounts of remaining open space. Protection of remaining open space and restoration of additional areas, especially forested areas, should be a priority in the urban core. There is an urgent need for additional information on stopover ecology and habitat requirements of Neotropical migrant landbirds. This information needs to be combined with an analysis of habitat status and trends in order to determine conservation priorities. Previous studies of the coastal corridor of the Delmarva Peninsula and adjacent areas have indicated the importance of the coastal corridor, especially coastal forests, to bird migration in that area; a continuation of these studies to include the coastline of the New York Bight and southern New England would help to focus conservation efforts for the entire migratory corridor along the East Coast. Protection of concentration areas such as Cape May will not be sufficient; Neotropical migrants require more extensive areas during migration, especially along the coast.
National and international efforts, such as Partners in Flight, to better understand and conserve Neotropical migrants are necessary to coordinate and focus state and regional efforts and should continue to be supported by state and federal agencies.
References:
Andrle, R.F. and J.R. Carroll (eds.) 1988. The Atlas of Breeding Birds in New York State. A project of the Federation of New York State Bird Clubs, Inc., New York State Department of Environmental Conservation, and Cornell Laboratory of Ornithology. Cornell University Press, Ithaca, NY. 551p.
Askins, R.A. 1993. Population trends in grassland, shrubland, and forest birds in eastern North America. Current Ornithology 11:1-34.
Askins, R.A., J.F. Lynch, and R. Greenberg. 1990. Population declines in migratory birds in eastern North America. Current Ornithology 7:1-57.
Dunne, P., R. Kane, and P. Kerlinger. 1989. New Jersey at the crossroads of migration. New Jersey Audubon Society, Franklin Lakes, NJ. 74 p.
Kane, R. and P. Kerlinger. 1994. Raritan Bay wildlife habitat report with recommendations for conservation. New Jersey Audubon Society, Bernardsville, NJ. 24 p.
Mabey, S.E., J. McCann, L.J. Niles, C. Bartlett, P. Kerlinger. 1993. The Neotropical migratory songbird coastal corridor study final report. A report of the Virginia Department of Environmental Quality to the National Oceanic and Atmospheric Administration Office of Ocean and Coastal Resource Management pursuant to NOAA award #NA90AA-H-CZ839.
New Jersey Audubon Society. 1995. New Jersey breeding bird atlas data from 1993 and 1994. Unpublished data, Cape May, NJ.
Robbins, C.S., D.K. Dawson, and B.A. Dowell. 1989. Habitat area requirements of breeding forest birds of the Middle Atlantic States. Wildlife Monographs 103:1-34.
Rosenberg, K.V. and J.V. Wells. 1995. Importance of geographic areas to Neotropical migrant birds in the Northeast. Report submitted to U.S. Fish and Wildlife Service Region 5, Hadley, MA.
Schneider, K.J. and D.M. Pence (eds.) 1992. Migratory nongame birds of management concern in the Northeast. U.S. Department of the Interior, Fish and Wildlife Service, Newton Corner, MA.
Smith, C.R., D.M. Pence, and R.J. O'Connor. 1993. Status of Neotropical migrant birds in the Northeast: a preliminary assessment. In D. Finch and K Stangel (eds.) Status and management of Neotropical migrant birds. U.S. Forest Service, Gen. Tech. Report RM-229, Fort Collins, CO.
Sauer, J.R. and S. Droege. 1992. Geographic patterns in population trends of Neotropical migrants in North America. In J.M. Hagan III and D.W. Johnston (eds.) Ecology and Conservation of Neotropical migrant landbirds, pp. 26-42. (Papers from the symposium hosted by Manomet Bird Observatory, Dec. 6-9, Woods Hole, MA). Smithsonian Institution Press, Washington, D.C.
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