BIRD CONSERVATION the Magazine of American Bird Conservancy Spring 2011 BIRD’S EYE VIEW
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BIRD CONSERVATION The Magazine of American Bird Conservancy Spring 2011 BIRD’S EYE VIEW Circular Reasoning: Understanding Neotropical Migrant Bird Conservation American Redstart: Greg Lavaty magine the annual cycle of mi- gratory birds as a stylized spiral resembling a nautilus whose Ichambers represent months of the year, shaded to indicate migration periods. Instead of being open-ended, the shell’s two ends abut, the narrow end representing the annual low pop- ulation point (immediately preceding breeding), and the broad end repre- senting the annual high population (immediately post-fledging). Across the year, the shell’s diameter tapers as population decreases due to preda- tors, severe weather, collisions with glass and communication towers, toxic poisoning, headwinds migrating across the Gulf of Mexico, habitat loss on the wintering grounds, and all of the other factors bird-lovers lament. Sketch by George Fenwick It looks simple, but it is not: the shape of the nautilus changes for every species and every year. Drought terms) always opine, “Why pick on us scope or scale of mortality factors to can mean low water, allowing water- when habitat loss is the big problem prioritize our work, to always make fowl to reach deeper into mud for for birds?” While that may be true, the best conservation decisions, to an- food, potentially gleaning decades-old we don’t often know exactly which ticipate the effects of acting on those lead shot and thus earning a painful factor – or, more likely, combination decisions, or even to evaluate after we death. Alternatively, flooding scours of factors – is contributing most to a have taken action. Scientists are giving river banks and islands, re-describing population decline. These factors can us a growing body of applicable data, nesting habitat for endangered Inte- be cumulative: multi-year droughts but we still have many “black boxes” rior Least Terns. Scientists from the or permanent nesting habitat loss, which await further investigation. institute for bird Populations have combined with the annual gauntlet of Revealing what is in these boxes, and learned that in La Niña years, winter other factors, can reduce bird popu- what it means for our neotropical mi- precipitation is low in western Mexico lations forever. And where a species grants, may be the best way for us to and high in eastern Mexico. This does not fill its available breeding understand our most pressing scientific matters because they discovered that, habitat in spring, as is sometimes the challenges in bird conservation. in the following spring, American case, we can conclude that breeding Redstarts breed poorly in the western habitat is not the only – or even most United States, but more successfully significant – limiting factor. in the East. The real problem is that although George Fenwick Opponents to ABC advocacy ef- birds may be among the best-known President, abc forts to reduce mortality in birds (or classes of animal life, we don’t know enhance survivorship, in scientists’ nearly enough about the relative 2 bird conservation • sPRING 2011 COVER PHOTO: Cerulean Warbler: Lloyd Spitalnik Kentucky Warbler: Greg Lavaty BirD Conservation Bird Conservation is the magazine of American Bird Conservancy (ABC), and SPRING 2011 is published three times yearly. American Bird Conservancy (ABC) is the only 501(c)(3) organization that works Bird Conservation solely to conserve native wild birds and their habitats throughout the Americas. A copy of the current financial statement and registration filed by the organization may be Throughout the Year obtained by contacting: abc, P.o. box 249, The Plains,VA 20198. tel: (540) 253-5780, or by contacting the following state agencies: 7-9 Effective Bird Conservation Florida: Division of Consumer Services, toll-free number within the State: Throughout the Year PAGE 10 800-435-7352. Maryland: For the cost of copies and postage: Office of the Secretary of State, statehouse, annapolis, Md 21401. 10-12 Providing a safe Haven for Migrants New Jersey: attorney General, state of new Jersey: 201-504-6259. While Protecting the Worthen’s sparrow New York: office of the attorney General, Department of Law, Charities Bureau, 120 broadway, new York, nY 10271. 13-15 Do Cerulean Warblers Pennsylvania: Department of State, toll-free number within the state: Like Chocolate? PAGE 13 800-732-0999. stock.xchng Virginia: State Division of Consumer Affairs, Dept. of Agriculture and Consumer 16-17 Introducing Southern Wings services, P.o. box 1163, richmond, VA 23209. West Virginia: Secretary of State, State Eliminating Threats to Migrating Capitol, Charleston, WV 25305. 18-20 Bird in the Yucatán Peninsula Registration does not imply endorsement, approval, or recommendation by any state. American Bird Conservancy is not responsible for unsolicited manuscripts 21-23 Wings and Wind Power — or photographs. Approval is required for PAGE 18 reproduction of any photographs or artwork. Proceed with caution Blue-winged Warbler: Editors: PAGE 6 Greg Lavaty Jack Morrison, Merrie Morrison, Michael J. Parr, david Pashley, DEPARTMENTS Gemma radko, Gavin shire, George e. Wallace 3 Bird’s Eye View For information contact: PAGE 24 American Bird Conservancy 4 On The Wire 4249 Loudoun avenue P.o. box 249 Female Yellow-billed Cotinga Species Profile The Plains,VA 20198 24 fitted with radio transmitter. 540-253-5780 Photo: Karen Leavelle Baltimore Oriole Web: www.abcbirds.org Baltimore Oriole: Greg Lavaty Email: [email protected] ABC’s Bird Conservation magazine brings you the best in bird conservation news and features. For more informa- tion on American Bird Conservancy, please visit our website at www.abcbirds.org or call 1-888-BIRD-MAG. bird conservation • sPRING 2011 3 ON THE WIRE Gorgeted Puffleg - The World’s Most Endangered Hummingbird? esults of surveys of the critically According to ABC’s Conservation Projects endangered Gorgeted Puffleg in Specialist Benjamin Skolnik, “Searches in Colombia have confirmed the spe- similar areas throughout the country have Rcies' precarious status and extremely turned up empty. This bird is truly rare, and limited range. The puffleg was discovered the best estimates suggest that only around and described in 2007 from the highest 100 individuals remain in the wild. It is hard cloud forest peaks of the Pinche Mountains to place value on such a magnificent hum- in Colombia between 9,100 to 10,100 feet. mingbird, and I hope people come to cherish It is a small, mostly dark hummingbird with this little bird like any other jewel.” bright white ‘puffs’ on its legs and an irides- The main threat to the Gorgeted Puffleg is cent green and violet throat. rapidly advancing habitat clearance across Throughout 2010, ABC funded its Colom- its tiny, unprotected range. Pristine forests Gorgeted Puffleg: Alex Cortes, Birdlife International bian partner Fundación ProAves under the and páramo (glacier-formed valleys and William Belton Grants Program to undertake plains with a large variety of lakes, peat regional searches across all of the upland bogs, and wet grasslands intermingled with Armed with this new information, ABC and massifs in the southern and central Western shrublands and forest patches) are being ProAves are eager to begin protecting the Cordillera of Colombia. destroyed by fires set in the dry season, species within its limited range. Residents of one of the local communities have ex- The surveys confirmed that the species which spread upslope to the fragile tree line. As a result, the Gorgeted Puffleg may be pressed interest in working to establish bet- occurs at extremely low densities (approxi- ter protection of the upper watershed where mately one individual per acre) within an the most endangered hummingbird on the planet. the bird is found, which would also ensure extremely limited potential range of likely no continued water security for them and other more than 2,700 acres. communities. Study Highlights the Impact of Cat Predation on Young Birds recent study that tracked Gray Cat- The study also found that predation was the ABC has a wide variety of materials avail- bird fledglings in three Washington, most significant factor affecting a catbird able on its website to help address the D.C. suburbs found that outdoor cats fledgling’s survival—not parental age, brood problems caused by free-roaming cats: A were the leading source of known size, sex, or hatching date. The vast major- www.abcbirds.org/abcprograms/policy/cats/ predation on the young birds. This study, ity of the deaths occurred in the first week materials.html published in the January 2011 edition of the after the bird fledged from the nest. Because A complete copy of the study is available at: Journal of Ornithology, was conducted by fledglings beg loudly for food and are not http://nationalzoo.si.edu/scbi/migratorybirds/ Dr. Peter Marra and Dr. Thomas Ryder of yet alert to predators, they are easy prey for science_article/pdfs/55.pdf The Smithsonian Institution and Ms. Anne L. cats and other predators. Balogh of Towson University. “This study certainly adds more validation to In the study, small radio transmitters were what we have been saying for years—that attached to 69 newly hatched catbirds. outdoor cats are a highly destructive preda- These transmitters recorded the birds’ loca- tory force that is causing havoc in the world tions every other day until they died or left of native wildlife. I hope we can now stop the study area. Forty-two birds died during minimizing the impacts that outdoor cats the study—33, or almost 80%, due to preda- have on the environment, and start address- tion. Almost half of the known predators ing the serious problem of cat predation,” were free-roaming cats. remarked Darin Schroeder, Vice President for Conservation Advocacy at ABC. bird conservation • sPRING 2011 4 Photo: stock.xchng SPRING CONSERVATION CHALLENGE Cerulean Warbler, Wood Thrush, Mountain Plover, Sprague’s Pipit: some of the migrants featured in this issue of Bird Conservation are birds many of us are lucky enough to see each spring.