The Marsh Wren Braddock Bay Bird Observatory
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Spring 2014 www.bbbo.org The Marsh Wren Braddock Bay Bird Observatory A non-profit organization dedicated to ornithological research, education, and conservation. Birds of a Different Color Leucism in Wild Birds During the fall of 2013, we captured several birds that had unusually pale feathers in atypical locations. While there has recently been some discussion about the proper terminology for such birds, both David Sibley and the Cornell Lab of Ornithology call these birds leucistic. The colors in birds’ feathers come from two sources: from pigments and from the structure of the feather itself. Melanins are the pigments responsible for brown, black, and some yellow; carotenoids are responsible for yellow and orange; and porphyrins are responsible for a range of hues including pink, red, brown, and some green. Iridescence as well as most blue comes not from pigment but from the structure of the feathers and the way they refract light. Leucism refers to the abnormal lack of melanin (and perhaps other pigments) in feathers. In most cases, leucism is caused by a genetic mutation that affects the way melanin More common are leucistic birds that have some white is deposited. Consequently, leucistic birds will have some patches but which are normally colored otherwise. These white or exceptionally pale feathers. birds are termed pied or piebald. A third variation is a fairly Leucistic birds come in three general varieties. Some uniform reduction in color all over the bird. leucistic birds are completely white, but with dark eyes. Albinism, a genetic mutation that prevents the production of melanin, is a similar condition but is far less common. It is interesting that not all albino birds are the stereotypical white-with-pink-eyes. Because albinism only affects the production of melanin, an albino bird might still produce other pigments and hence appear colored. These birds do not survive long in the wild, as the lack of melanin in the eyes affects their sight. Since leucism is typically a genetic mutation, it affects each generation of feathers. However, sometimes we see birds that appear to be leucistic one year, and normal the next. In most cases, it is likely to be tail feathers that switch between the typical and atypical condition. The Cedar Waxwing tail to the left may be an example of this phenomenon. The four white rectrices may have regrown after an accidental loss, Top: American Robin with pied leucism. Photo by Andrea Patterson. Above right: White-throated Sparrow with pied leucism. Photo by Peggy Keller. Left: Cedar Waxwing with white tail feathers. Photo by Andrea Patterson. and they may be replaced with normal gray feathers during genetic mutation is affecting just one type of melanin. It is the next regular molt cycle. Some sources count this as an also possible that it is affecting all types, such that they are example of leucism while some do not, as it is likely not a deposited at much lower concentrations. genetic condition. Finally, leucism isn’t just a condition that affects the feathers. The White-throated Sparrow to the left displays a “common” In the case of the Gray Catbird above, it has affected the pattern of leucism in this species. BBBO volunteer Cindy claws. Marino reports seeing one at her feeders, Black Swamp Keep an eye out for leucism. These birds are uncommon, Bird Observatory has banded two in the last 25 years, and but with a careful eye you may well see leucistic birds at multiple photos and videos exist on the internet of similar your feeders, in your yard, or on your bird walks. birds. We joke that there are actually three morphs of the White-throated Sparrow: white, tan, and the rare bald- Top left: Leucistic and typical Bay-breasted Warblers. The bird on the eagle! left may simply have a lower concentration of melanistic pigments, or it may be missing a particular type of melanin. Photo by Kyle Horton. When the bird is pale and washed out, as the Bay-breasted Top right: Gray Catbird with leucistic claws. Photo by Cindy Marino. Warbler above (banded fall 2011), it is possible that the BBBO Honors Betsy’s Commitment to Education! On October 3, BBBO hosted its first ever science talk in the newly renovated education space. Sara Morris’s talk was well attended, interesting, and engaging . and it was all a cover! The real purpose of the evening was to honor Betsy Brooks and her many years of service. Given all the work Betsy has done educating banders, volunteers and the public, it is exceptionally fitting that the Board of Directors has chosen to name the education space theElizabeth W. Brooks Center for Learning about Migratory Birds. Congratulations Betsy! Photos by Kathy Habgood. including 22 Ruby-throated Hummingbirds (previous record high 10); 18 Eastern Wood Pewee (9); 42 Yellow- Fall Banding bellied Flycatcher (39); 126 Cedar Waxwing (110); and 9 Blackburnian Warbler (7). On the negative side, 19 Black-capped Chickadees was our lowest fall total ever. 2013 Yellow-bellied Sapsucker was missing after being banded in 16 of the last 18 years; Rusty Blackbird was missing he twenty-eighth consecutive year of fall banding after being banding in 15 of the last 18 years; and White- at the Kaiser-Manitou Beach Banding Station breasted Nuthatch, Scarlet Tanager and Indigo Bunting began on 21 Jul and ended on 25 Oct 2013, with were missing after being banded in 14 of the past 18 years. Tthe intensive season starting on 17 Aug. 4,512 birds of A milestone was reached on 22 Jul, when BBBO banded 87 species were banded, which falls short of fall 2012’s its 200,00th bird - the second-year male Cedar Waxwing total by 1,058 birds. An additional 26 Ruby-throated pictured on the cover. Hummingbirds were released unbanded. Gambel’s White- crowned Sparrow was a new form for the cumulative fall list, which now stands at 130 forms. A total of 15,292 net Education and Events Fall 2013Fall Banding Report hours of banding resulted in a capture rate of 29.5 birds Amy Haus (Germansville, PA), Jessica Howell (Ohio per 100 net hours, compared with 37.8 birds per 100 net University), Megan Nephshinsky (Hull, MA), Danica hours in fall 2012. Schaffer-Smith (Duke University), Pam Westrom The busiest day was 25 Sep when 241 birds of 25 species (Chestnut Hill, MA), Nichole Whyland (Cornell were banded. On that day, the predominant species were University), and Robert Zimmerman (Northampton, MA) White-throated Sparrow (32%) and Golden-crowned participated in our first ever Summer Bander Training Kinglet (19%). There were three additional 200+ bird days Course. and four additional 100+ bird days. The greatest species Alan Belford (Saranac Lake, NY), Elizabeth Lamont diversity occurred on 26 Sep and 2 Oct when 27 species (Hillard, OH), Kendra Ormerod (Saranac Lake, NY), were banded. Of the new bandings, 84.9% were Hatch Lisa Schofield (Holley, NY), Stephanie Slonka (UMass Year (HY) birds. Amherst), and Robbie Tietge (Two Harbors, MN) In addition to the “new” birds, we recaptured 1,375 participated in our Fall Bander Training Class. previously banded birds. Of these recaptures, 62 returned During the fall season, we welcomed guests from SUNY from a previous season, and 8 returned after being banded ESF, SUNY Geneseo, Hobart and William Smith Colleges, at the Kaiser-Manitou Beach MAPS station. Noteworthy the Harley School, and several home-school groups. Part among these were two Red-eyed Vireos and a Gray of the Appledore Island (Shoals Marine Lab) banding Catbird each in their eighth years; an American Redstart station staff ran the station for a weekend, and we also and a Northern Cardinal in their seventh years; a Black- hosted a North American Banding Council certification capped Chickadee, an American Robin, and a Common session. Visitors from ten states, Ontario, and Kenya Yellowthroat in their sixth years; and a Red-eyed Vireo signed our guest book. and two Gray Catbirds in their fifth years. The station held two special events. Sarah Morris gave There were record-high numbers banded of 5 species a science talk that served as cover for the dedication of the education room to Betsy. We also held a “Breakfast with the Birds” for special guests of WXXI in Rochester. Research Technical problems prevented Dr. Sara Morris and her assistant Katie Little from operating the MARS trailer this fall. We collected blood samples from thrushes, Blackpoll Warblers and White-throated Sparrows for Dr. Susan Smith Pagano of R.I.T., who is using plasma indicators of fattening rates and diet to study the migration physiology and stopover site use of these birds. We also collected blood samples from Black-throated Blue Warblers for Sara Kaiser and Scott Taylor of Cornell University, who are interested in developing a better paternity test, in order to Top 10 species banded during fall 2013 2013Fall Banding Report With numbers captured during previous 10 fall seasons 2003 2004 2005 2006 2007 2008 2009 2010 2011 2012 2013 White-throated Sparrow 1569 1146 1516 674 1037 554 839 1459 551 785 848 Golden-crowned Kinglet 193 473 502 458 295 341 324 360 176 343 456 Ruby-crowned Kinglet 221 702 722 619 510 420 521 321 193 341 287 Magnolia Warbler 220 188 170 270 309 350 316 295 132 183 284 Gray Catbird 163 102 175 138 236 266 157 230 164 290 273 Hermit Thrush 414 307 450 171 200 186 186 217 210 288 203 Blackpoll Warbler 40 47 78 65 162 343 52 280 760 575 182 Yellow Warbler 58 49 123 31 142 180 157 321 30 126 162 Swainson’s Thrush 150 159 165 123 177 147 60 176 75 306 134 Cedar Waxwing 96 13 36 69 85 59 110 56 33 28 126 more effectively study the mating system of these warblers.