In September, the U.S. Fish and Wildlife Service denied a petition to put the Bicknell’s thrush (Catharus bicknelli) on the federal list of endangered species. The Bicknell’s is a medium-size (6-7.5 inches) thrush—brown on the back with a white, spotted underside—that dwells in dense balsam-fir forests in high elevations in the Adirondacks. Following is a primer on other wildlife in trouble in the Adirondack Park.
Once common, Whip-poor-wills (Caprimulgus vociferus) and other nocturnal nightjar (Caprimulgus europaeus) species are disappearing from Illinois forests as their habitats shrink and change, according to data from the Illinois Natural History Survey (INHS), a division of the University of Illinois’ Prairie Research Institute. “Because they are nocturnal, monitoring for nightjars can be challenging, but we suspect that they are declining,” said Tara Beveroth, an INHS avian researcher.
A 16-year study of mountain forest songbirds across New York and New England, including thrushes, warblers and other iconic species, has documented their population changes. Although species like Black-capped Chickadee and Swainson’s Thrush have thrived in the mountains during recent decades, some species that depend on the region’s evergreen forests of spruce and fir – notably Blackpoll Warbler – appear to have undergone substantial declines.
Numerous North American songbird populations are declining, and conservationists are not sure why – although 10 years of data indicate the reasons may be as varied as the birds themselves. Theories about why these bird populations are declining include reproductive issues and poor survival rates of adults, as well as possible changes in environmental conditions.
The population of endemic babblers at the Mount Kanlaon Natural Park on Negros Island continues to drop owing to habitat loss and human-induced air pollution, a study published recently in the Sylvatrop Journal of the Ecosystems Research and Development Bureau (ERDB) of the Department of Environment and Natural Resources (DENR).
Based on monitoring data for the period 2005-2010, we studied the trends in abundance and species richness of common breeding birds in Bulgaria before and after the country joined the EU in 2007. We analysed the trends in birds of farmland, woodland and “other” habitats, and additionally, we tested whether indices of the commonest birds are representative of wider changes in bird populations. At species level (n = 32), significant declines were detected in 11 species (34%), and increases in just two (6%); 19 species (60%) had uncertain trends.
The red-headed woodpecker (Melanerpes erythrocephalus) was once a very common woodpecker. In the mid-1800s, John James Audubon stated that the red-headed woodpecker was the most common woodpecker in North America. He called them semi-domesticated because they weren’t afraid of people. He stated that they were camp robbers and also a pest. According to the Audubon Society’s Christmas Bird Count data, between the 1950s and the year 2010, the population of red-headed woodpeckers dropped dramatically. Over 80 percent of the population died out in just over 50 years.
Wo sind all die Grünfinken (Chloris chloris, Syn.: Carduelis chloris) geblieben? 2012 rangierte der possierliche Singvogel, der als einziger sogar in Thujenhecken nistet, mit 230.000 Brutpaaren noch auf Platz vier der häufigsten Vogelarten. Doch jetzt geht es mit ihm rapide bergab. "Seine Bestände haben sich mehr als halbiert", sagt Susanne Schreiner von BirdLife. Schuld ist der Einzeller "Trichomonas gallinae", der im Kropf schwere Entzündungen auslöst. Zwar hat er es auch auf andere Vogelarten abgesehen. Todbringend ist er aber fast nur für Grünfinken.
THE latest results from the Breeding Bird Survey (BBS) show that everything might not be as it seems, with many of our woodland birds in trouble. The BBS report, published by the British Trust for Ornithology in partnership with the Joint Nature Conservation Committee (JNCC) and the RSPB shows trends for 111 species in the UK and makes interesting reading. Being a woodland bird in the UK is a bit of a rollercoaster ride, depending on which species you are.