Avian community structure and habitat use in a Southern New England estuary

Abstract

The habitat use of 126,566 birds observed in a 158-ha tidal pond/salt marsh complex in southeastern Massachusetts was recorded during 218 fixed-width transect and 241 remote-count censuses conducted year-round over 5 years (June 1985-May 1990. The most abundant bird groups overall were waterfowl, gulls, shorebirds, and songbirds. Overall avian abundance was greatest in the fall and winter. Avian richness ranged from a mean of 15 species in winter to 26 in summer; 131 species were sighted overall. Waterfowl, shorebirds, and gulls used tidal pond habitats (including flats) to a greater extent than marsh habitats; use of marsh habitats increased with tidal stage for each of those groups. Wading birds were more abundant in marsh habitats than in pond habitats, and songbirds used marsh habitats exclusively. The permanently flooded (subtidal) west portd segment was used to the greatest extent by cormorants and diving ducks and least by shorebirds and wading birds. Tidal stage influenced abundance patterns of shorebirds and gulls and activity patterns of shorebirds, gulls, and waterfowl. Time of day influenced abundance patterns of guUs. All macrohabitat types (intertidal and subtidal pond, emergent marsh) were used to a substantial degree by multiple bird groups indicating that the loss or disturbance of any type could negatively affect the estuarine avifauna.

Impact of the spread ofPhragmites on the distribution of birds in Connecticut tidal marshes

“…Clapper Rail, however, eften nest in saltwater cordgrass marshes (Daiber 1982, references therein). Because an inverse relationship between the abundance of marsh specialists and percent cover of open water has previously been shown (Craig and Beal 1992), it is not surprising that generalists dominated these sites where they could find plenty of shallow water for foraging (Slavin and Shisler 1983, Reinert and Mello 1995). Although Willet abundance was correlated with presence of S. alterniflora, they prefer higher, drier ateas for nesting and use wetter sites for foraging (Burger andShisler 1978, Howe 1982).…”

Development of a reference coastal wetland set in Southern New England (USA)

“…In contrast to the high species richness and abundance of waterfowl at the urbanized wetlands in apparently poor condition, other reports for New England salt marshes suggest that degraded salt marshes provide poor breeding habitat for marsh specialists such as seaside and sharp-tailed sparrows (i.e., Ammodramus maritimus and A. caudacutus; e.g., Stoll and Golet 1983;Reinert and Mello 1995;Brawley et al 1998). In addition, in highly altered marshes the lower plant species richness and the trend toward a more homogenous landscape dominated by tall S. alterniflora and the invasive P. australis lowers the habitat value for some fish and bird species (Benoit and Askins 1999;Deegan 2002;Able et al 2003).…”

“…At degraded salt marshes, declines in the extent of S. patens and short S. alterniflora, marsh vegetation where sparrows are known to nest, were associated with lower abundances of these marsh specialists (e.g., Stoll and Golet 1983;Reinert and Mello 1995;Brawley et al 1998). In the present study, high areal extent of S. patens and short S. alterniflora was a characteristic of salt marshes in least altered condition.…”

Avian communities inSpartina maritimarestored and non-restored salt marshes

“…Zedler 1993). Ecological restoration that increases habitat heterogeneity has been linked to diversity and abundance of salt marsh birds (Greenlaw 1983, Craig & Beal 1992, Reinert & Mello 1995. Restored salt marshes provide new habitats for obligate species, which breed and forage only in salt and brackish marshes, and facultative species, which breed or forage in other habitats as well (Lewis & Casagrande 1997).…”