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Eastern Phoebe (Sayornis Phoebe) Torrey Wenger

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Eastern Phoebe (Sayornis Phoebe) Torrey Wenger Eastern Phoebe (Sayornis phoebe) Torrey Wenger Shiawassee State Game Area, Saginaw Co., MI. April, 2009 © Willie McHale This species sponsored by John Talbot & Nora Iverson. (Click to view a comparison of Atlas I to II) Returning to Michigan in March, the Eastern sites, leading them to pair with their previous Phoebe and its distinctive “fee bee” song is one mate (Weeks 1994). Depending on the of the first guarantees of spring. The ability to substrate, the mud-moss-and-grass nests are switch to fruits during inclement weather – either attached to a vertical surface (i.e., a wall) unlike the flying-insect-only diet of other or placed on a horizontal surface (i.e., a barn flycatchers – enables the newly arrived birds to rafter); in all cases, the nest is tucked under a survive the sometimes capricious weather of protective overhang. Five eggs are typically early spring (Weeks 1994). Phoebes readily laid and take about two weeks to hatch. Only accept man-made structures as nest sites and the female incubates. The young can fledge as have expanded their range both west and south early as two weeks but may stay in the nest for as a result (Weeks 1994). The combination of another week (Weeks 1994). close proximity to human sites, early arrival, and easily recognized song makes the phoebe a Phoebes will reuse nests from previous years bird familiar even to non-birders. and will also make use of the old nests of other birds, such as Barn Swallow and American Distribution Robin. Nest reuse increases success, allowing Phoebes can be found in all counties throughout the pair to lay eggs sooner and renest sooner, the state, including Isle Royale. This is but does not affect clutch size (Hauber 2002). essentially unchanged from MBBA I. Old nests are always “renovated” and the Statewide, they were documented in 66% of all presence of green moss is diagnostic of a townships surveyed during MBBA I and in 75% phoebe nest, no matter the original builder during MBBA II, a net increase of 14%. The (Weeks 1994). proportion of townships occupied in the SLP and UP increased by 21% and 23%, Cowbirds are frequent nest parasites of phoebe respectively; that in the NLP decreased by 3%. nests. Parasitism rates vary by region and documented rates range from 0% to 42% Breeding Biology (Weeks 1994, Ortega 1998). About 70% of Pair formation occurs quickly after birds arrive parasitized nests produced only cowbirds, 10% in mid-March, later in the UP. Adults exhibit produced both phoebes and cowbirds, and 20% strong site fidelity and return to previous nesting produced only phoebes (Weeks 1994). © 2010 Kalamazoo Nature Center Eastern Phoebe (Sayornis phoebe) Torrey Wenger Parasitized nests fledged 0.75 phoebes (and 1.25 1994). As a short-distance migrant, the phoebe cowbirds) while non-parasitized nests fledged is responding to global climate change – it is 3.78 phoebes; egg success rates are more arriving about 20 days earlier in the spring than dramatic, with only 17% of phoebe eggs (and it did 60 years ago (Bradley et al. 1999). 71% of cowbird eggs) producing fledglings in parasitized nests compared to 89% of eggs in The phoebe is a solitary bird – even mated pairs non-parasitized nests (Berger 1951). Phoebes spend most of their time apart – and would are tolerant of cowbird parasitism and do not benefit from increased study. Since it does not abandon the nest or remove the eggs (Rothstein move in large flocks, little is known about its 1986). migration or winter range. Few studies have been done on its food choices, or on how long Abundance and Population Trends the fledged young remain dependent on their (Click to view trends from the BBS) parents. These questions are important when The phoebe is an abundant bird with a growing planning for the long-term conservation of this population. BBS data show positive trends at species. This charming bird of mystery would all levels: survey-wide, an annual increase of be a good candidate for citizen science-style 0.8% (P = 0.00, n = 2069) during the 1966-2007 research. period; an increase of 2.2% annually in USFWS Conservation Region 3; and in Michigan, an Literature Citations insignificant increase of 3.0% (Sauer et al. Berger, A.J. 1951. The cowbird and certain host 2008). species in Michigan. Wilson Bulletin 63:26- 34. The second atlas of Ontario reported increases Bradley, N.L., A.C. Leopold, J. Ross, and W. in both probability of observation and Huffaker. 1999. Phenological changes population (McLaren 2007); in New York, their reflect climate change in Wisconsin. second atlas found phoebes in 9% more blocks Proceedings of the National Academy of than their first atlas (McGowan 2008). This Sciences 96(17): 9701-9704. species is common in states throughout the Hauber, M.E. 2002. Is reduced clutch size a cost Great Lakes region, although the first Ohio atlas of parental care in Eastern Phoebes noted reduced numbers in some areas due to (Sayornis phoebe)? Behavioral Ecology and habitat loss (Peterjohn and Rice 1991). Sociobiology 51(6): 503-509. McGowan, K.J. 2008. Eastern Phoebe. In Conservation Needs McGowan, K.J. and K. Corwin (eds.). The The near future of the Eastern Phoebe is secure. Second Atlas of Breeding Birds in New York This species is tolerant of human activity and State. Cornell University Press. Ithaca, NY. will nest on man-made structures, ensuring it McLaren, M.A. 2007. Eastern Phoebe. In potential habitat for years to come. Bridges Cadman, M.D., D.A. Sutherland, G.G. Beck, designed to provide nest-building sites could D. Lepage, and A.R. Couturier (eds.). 2007. help this species and others. Phoebes do require Atlas of the Breeding birds of Ontario, woody vegetation close to the nest site (Weeks 2001-2005. Bird Studies Canada, 1994) so conscientious landscaping might be Environment Canada, Ontario Field required. Ornithologists, Ontario Ministry of Natural Resources, and Ontario Nature. Toronto, Populations wintering in the southeastern U.S. ON. and Mexico are vulnerable to severe weather events. Some mortality of young birds is due to nests parasites (i.e., lice) in reused nests (Weeks © 2010 Kalamazoo Nature Center Eastern Phoebe (Sayornis phoebe) Torrey Wenger Ortega, C.P. 1998. Cowbirds and Other Brood Sauer, J.R., J.E. Hines, and J. Fallon. 2008. The Parasites. The University of Arizona Press. North American Breeding Bird Survey, Tucson, AZ. Results and Analysis 1966-2007. Version Peterjohn, B.G., and D.L. Rice. 1991. The Ohio 5.15.2008. USGS Patuxent Wildlife Breeding Bird Atlas. The Ohio Department Research Center. Laurel, MD. of Natural Resources Division of Natural Weeks, H.P, Jr. 1994. Eastern Phoebe (Sayornis Areas and Preserves. Columbus, OH. phoebe). In The Birds of North America, No Rothstein, S.I. 1986. A test of optimality: egg 94 (A. Poole and F. Gill, eds.). The Birds of recognition in the Eastern Phoebe. Animal North America, Inc., Philadelphia, PA. Behaviour 34: 1109-1119. © 2010 Kalamazoo Nature Center .
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