A catalog of Louisiana's nesting seabird colonies
Summarizing his colonial nesting waterbird survey experiences along the northern
coast of the Gulf of Mexico in a paper presented to the Colonial Waterbird Group of the
Waterbird Society (Portnoy 1978), bird biologist John W. Portnoy stated, “This huge
concentration of nesting waterbirds, restricted almost entirely to the wetlands and
estuaries of southern Louisiana, is unmatched in all of North America; for example, a
1975 inventory of wading birds along the Atlantic Coast from Maine to Florida [Custer
and Osborn, in press], tallied 250,000 breeding [waterbirds] of 14 species, in contrast
with the 650,000 birds of 15 species just from Sabine Pass to Mobile Bay.” The “650,000
birds” to which Portnoy referred, were tallied by him in a 1976 survey of coastal
Louisiana, Mississippi, and Alabama (see below, under “Major Surveys” section).
According to the National Atlas of Coastal Waterbird Colonies in the Contiguous
United States: 1976-82 (Spendelow and Patton 1988), the percentages of the total U.S.
populations of Laughing Gull (11%), Forster's Tern (52%), Royal Tern (16%), Sandwich
Tern (77%), and Black Skimmer (44%) which annually nest in Louisiana are significant –
perhaps crucially so in the cases of Forster's Tern, Sandwich Tern, and Black Skimmer.
Nearly three decades after Spendelow and Patton's determinations above, coastal
Louisiana still stands out as the major center of colonial wading bird and seabird nesting
in all of the United States. Within those three intervening decades, however, the
collective habitats which comprise Louisiana's now fragile coastal zone have taken major
hits from commercial/residential, oil & gas, and other industrial development, primarily
in the form of coastal erosion exacerbated by these and other factors (Portnoy 1978,
Spendelow and Patton 1988, Martin and Lester 1990, Green, et al. 2006). Moreover,
during this same period, both geologic subsidence rates (Tornqvist et al. 2008) and mean
sea-level (Tornqvist et al. 2002) have increased, along with significant tropical storm
activity; all of which have combined to impact available marsh, barrier island, beach, and
dredge spoil nesting habitat for waterbirds, especially seabirds, throughout the coastal
zone of Louisiana.
The primary objective of this publication is to detail those coastal Louisiana
colonial seabird nesting sites for which we have reasonably accurate data, in a tabular,
site-by-site format. All major survey (1976-2008) data of site-by-site seabird species
counts, as well as several smaller data sets, referred to in the site history tables as
“miscellaneous observations” obtained during the May-June seabird breeding period, are
included.
It is our hope that these data will provide a dependable foundation from which
future colonial seabird nesting surveys might be planned and carried out, as well as
showcase the importance of coastal Louisiana's seabird rookeries, and contribute to their
conservation.
Citation Information
Publication Year | 2012 |
---|---|
Title | A catalog of Louisiana's nesting seabird colonies |
Authors | William R. Fontenot, Steve W. Cardiff, Richard A. DeMay, Donna L. Dittmann, Stephen B. Hartley, Clinton W. Jeske, Nicole Lorenz, Thomas C. Michot, Robert Dan Purrington, Michael A. Seymour, William G. Vermillion |
Publication Type | Report |
Publication Subtype | State or Local Government Series |
Series Title | Barataria-Terrebonne National Estuary Program Report |
Series Number | 34 |
Index ID | 70047147 |
Record Source | USGS Publications Warehouse |