Key Findings from Bicknell's Thrush Winter Ecology Studies

OVER TWO DECADES OF INNOVATIVE STUDIES

1994-97 Bicknell’s Thrush distribution and habitat use study in the wintering grounds.

1997-2007 Intensive mid-winter demographic monitoring of BITH and other montane forest birds in Sierra de Bahoruco; includes training of local biologists.

• Constant-effort mist-netting, point counts, spot mapping
• 429 individual BITH captured in D.R. (490 total captures) and 22 individuals in Haiti (25 total captures)
• 2 VT-DR recoveries (Rimmer and McFarland 2001, Townsend and Rimmer 2006)
• BITH found in broadleaf forest fragments at mid- and high elevations (Rimmer et al. 2005, 2010)

1998-99 BITH surveys conducted in Blue and John Crow Mts of Jamaica.

• Low BITH numbers in Blue Mts, none found in John Crow Mts

1999 Yves Aubry initiated surveys in Cuba in 1999 with local collaborators Alejandro Llanes from the Instituto de Ecologia y Sistematica and Arturo Kirkconnell from the Museo Nacional de Historia Natural, both in La Havana.

• Many areas were visited throughout the island of Cuba. Bicknell’s Thrush was located only in the high altitude cloud forests of the Sierra Maestra. So far, no bird has been found at low elevations.

2001-07 BITH sexual habitat selection and overwinter ecology research (Jason Townsend PhD work)

• Data show 4:1 male:female ratio in undisturbed, primary montane forests of DR, 1:1 ratio in more disturbed, secondary montane forests.
• Males and females occupy discrete territories in primary forest of ~0.35 ha based on radio telemetry.

2001-07 Collection of mercury samples from Bicknell’s Thrush on Hispaniola and Cuba. Thrushes found to have 3x more mercury in winter grounds compared to breeding sites.

2004-07 Bicknell’s Thrush surveys conducted in two protected areas of Haiti (Macaya and La Visite). Thrushes found in broadleaf forest fragments at mid- and high elevations

2005 eBird Caribbean started to collect observations of Bicknell’s Thrush and other birds using crowd-sourced website.  

2008-2010 VCE coordinates field training workshops for Hispaniolan and Cuban conservation partners in Vermont and the DR (Cordillera Septentrional and Sierra de Bahoruco)

2009-present VCE joins Vermont partner AgRefresh and multiple Dominican partners to initiate a Payment for Ecosystems Services project focused on BITH, water quality, and carbon banking in the eastern Cordillera Septentrional

PUBLICATIONS

• Townsend, J.M., C.C. Rimmer, C.T. Driscoll, K.P. McFarland, and E.E. Iñigo-Elias. 2013. Mercury concentrations in tropical resident and migrant songbirds on Hispaniola. Ecotoxicology Volume 22 (1): 86-93. DOI 10.1007/s10646-012-1005-1. (Abstract)
• McFarland, K.P., C.C. Rimmer, J.E. Goetz, Y. Aubry, J.M. Wunderle Jr., A. Sutton, J.M. Townsend, A. Llanes Sosa, and A. Kirkconnell. 2013. A Winter Distribution Model for Bicknell’s Thrush (Catharus bicknelli), a conservation tool for a threatened migratory songbird. PLOS ONE 8(1): e53986. doi:10.1371/journal.pone.0053986. (Abstract)
• Townsend, J.M., C.C. Rimmer, K.P. McFarland, and J.E. Goetz. 2012. Site-specific variation in food resources, sex ratios and body condition of an overwintering migrant songbird. Auk 129: 683-690. (Abstract)
• McKinnon, E.A, K.C. Fraser, A.W. Diamond, C.C. Rimmer, and J.M. Townsend. 2012. Stable-hydrogen isotope turnover in red blood cells of two migratory thrushes: application to studies of connectivity and carry-over effects. Journal of Field Ornithology 83:306-314. (Abstract)
• Townsend, J.M., C.C. Rimmer, and K.P. McFarland. 2012. Radio-transmitters do not affect seasonal mass change or annual survival of wintering Bicknell’s Thrushes. Journal of Field Ornithology 83:295-301. (Abstract)
• Townsend, J.M., C.C. Rimmer, A.T. Townsend, and K.P. McFarland. 2011. Sex and age ratios of Bicknell’s Thrush wintering in Hispaniola. Wilson Journal of Ornithology 123:367-372. (Abstract)
• Townsend, J.M, C.C. Rimmer, and K.P. McFarland. 2010. Winter territoriality and spatial behavior of Bicknell’s Thrush (Catharus bicknelli) at two ecologically distinct sites in the Dominican Republic. Auk 127:514-522. (Abstract)
• Kerchner, C., M. Homzak, R. Kemkes, A. Richardson, J.M. Townsend, and C.C. Rimmer. 2010. Designing spatially explicit incentive programs for habitat conservation: a case study of the Bicknell’s Thrush winter grounds. Ecological Economics 69:2018-2015. (Abstract)
• Townsend, J.M., C.C. Rimmer, and K.P. McFarland. 2009. Investigating the limiting factors of a rare, vulnerable species: Bicknell’s Thrush. Proceedings of the Fourth International Partners in Flight Conference: Tundra to Tropics: 91-95. (PDF)
• Townsend, J.M., C.C. Rimmer, J. Brocca, K.P. McFarland, and A. K. Townsend. 2009. Predation of a wintering migratory songbird by introduced rats: can nocturnal roosting behavior serve as predator avoidance? Condor 111(3): 565-569. (Abstract)
• Townsend, J.M. and C.C. Rimmer. 2006. Known natal and wintering sites of a Bicknell’s Thrush. Journal of Field Ornithology 77: 452-454. (Abstract)
• Christopher C. Rimmer, Jason M. Townsend, Andrea K. Townsend, Eladio M. Fernández, & Jesus Almonte. 2005. Avian diversity, abundance, and conservation status in the Macaya Biosphere Reserve of Haiti. Ornitologia Neotropical 16: 219–230. (PDF)
• Rimmer, C.C. 2005. Bird conservation in Haiti: it’s now or never to save Haiti’s birds. Journal of Caribbean Ornithology 18:86-87. (PDF)
• Rimmer, C.C. and K.P. McFarland. 2001. Known breeding and wintering sites of Bicknell’s Thrush. Wilson Bull.113: 234-236. (Abstract)
• Hobson, K.A., K.P. McFarland, L.I. Wassenaar, C.C. Rimmer and J.E. Goetz. 2001. Linking breeding and wintering grounds of Bicknell’s Thrushes using stable isotope analyses of feathers. Auk 118:16-23. (Abstract)