: : . THE RAPTOR RESEARCH FOUNDATION, INC. (Founded 1966) http://biology.boisestate.edu/raptor/ OFFICERS PRESIDENT: Brian A. Millsap SECRETARY: Judith Hfnckel VICE-PRESIDENT: David M. Bird TREASURER: Jim Fitzpatrick BOARD OF DIRECTORS NORTH AMERICAN DIRECTOR #I INTERNATIONA!. DIRECTOR #3: Steve Hoffman S i eve Re.dpath NORTH AMERICAN DIRECTOR #2: DIRECTOR AT LARGE #1: Jemima ParryJones Gary Santolo DIRECTOR AT LARGE #2: Eduardo Inigo-Elias NORTH AMERICAN DIRECTOR #.3: DIRECTOR AT LARGE #3: Michael W. Collopy Ted Swem DIRECTOR AT I.ARGE #4: Carol McIntyre INTERNATIONAL DIRECTOR #I DIRECTOR AT LARGE #5: John A. Smallwood Nick Mooney DIRECTOR AT LARGE #6: Daniel E. Varland INTERNATIONAL DIRECTOR #2: Ruth Tingay ^ EDITORIAl. STAFF EDITOR: James C. Bednarz, Department of Biological Sciences, P.O. Box 599, Arkansas State University, State University, AR 72467 U.S A. ASSISTANT EDITOR: Jennifer L. Norris ASSOCIATE EDITORS James R. Beltiioff Joan L. Morrison Clint W. Boat Fabrizio Sergio Cheryl R. Dyksfra Ian G. Warkentin Michaei. L Goldstein James W. Watson BOOK REVIEW EDITOR: Jeffrey S. Marks, Montana Cooperative Research Unit, University of Montana, Missoula, MT 59812 U.S.A. SPANISH EDITORS: Carlos Daniel Cadena, Lucio R. Malizia, Cintia Cornelius EDITORIAI. ASSISTANT: Joan Clark The Journal of Raptor Research is distributed quarterly to all current members. Original manuscripts dealing with the biology and conservation of diurnal and nocturnal birds of prey are welcomed from throughout the world, but must be written in English. Submissions can be in the form of research articles, short communications, letters to the editor, and book reviews. Contributors should submit a typewritten original and three copies to the Editor. All submissions must be typewritten and double-spaced on one side of 216 X 278 mm ( 8V2 X 11 in.) or standard international, white, bond paper, with 25 mm (1 in.) mar- gins. The cover page should contain a title, the author’s full narae(s) and address (es). Name and address should be centered on the cover page. If the current address is different, indicate this via a footnote. A short version of the title, not exceeding 35 characters, should be provided for a running head. An abstract of about 250 words should accompany all research articles on a separate page. Tables, one to a page, should be double-spaced throughout and be assigned consecutive Arabic numer- als. Collect all figure legends on a separate page. Each illustration should be centered on a single page and be no smaller than final size and no larger than twice final size. The name of the author(s) and figure number, assigned consecutively using Arabic numerals, should be pencilled on the back of each figure. Names for birds should follow the A.O.U. Checklist of North American Birds (7th ed., 1998) or another authoritative source for other regions. Subspecific identification should be cited only when pertinent to the material presented. Metric units should be used for all measurements. Use the 24-hour clock (e.g., 0830 H and 2030 H) and “continental” dating (e.g., 1 January 1999). Refer to a recent issue of the journal for details in format. Explicit instructions and publication policy are outlined in “Information for contributors,”/. Raptor Res., Vol. 38(4), and are available from the editor. Submit manuscripts to J. Bednarz at the address listed above. COVER: “Vigilance” painting by Robert Bateman of Bald Eagle {Haliaeetus leucocephalus) ^Robert Bateman. Reproduction rights courtesy of Robert M. Bateman, Boshkung, Inc. (www.robertbateman.ca) Contents The Influence of Tide and Weather on Provisioning Rates of Chick-rearing Bald Eagles in Vancouver Island, British Columbia. Kyle Hamish Elliott, Christopher E. Gill, and John E. Elliott 1 First Complete Migration Cycles for Juvenile Bald Eagles {Haliaeetus LeUCOCEPHALUS) from Labrador. Dawn K. Laing, David M. Bird, and Tony E. Chubbs 11 Investigating Fall Movements of Hatch-year Flammulated Owls ( Otus FLAMMEOLUS) IN CENTRAL NeW MEXICO USING STABLE HYDROGEN ISOTOPES. John P. DeLong, Timothy D. Meehan, and Ruth B. Smith 19 Effects of Breeding Experience on Nest-site Choice and the Reproductive Performance of Tawny Owls {Strix aluco) . Lajos Sasvari and Zoitan Hegyi 26 The Status of Diurnal Birds of Prey in Turkey. Levent Turan 36 Short Communications Seasonal Diet of the Aplomado Falcon {Falco femoraus) in an Agricultural Area of Araucania, Southern Chile. Ricardo A. Figueroa Rojas and Ema Soraya Corales Stappung 55 Mesostigmatic Mites (Acari: Mesostigmata) in White-tailed Sea Eagle Nests {Hauaeetus albicilul) . DariuszJ. Gwiazdowicz, Jerzy Bloszyk, Tadeusz Mizera, and Piotr Tryjanowski 60 Vertebrate Prey of the Barn Owl ( Trro alba) in Subtropical Wetlands of Northeastern Argentina AND Eastern Paraguay. Ulyses F.J. Pardinas, Pablo Teta, and Sofia Heinonen Fortabat 65 Absence of the Eurasian Griffon (Gypsfulvus) in Northern Morocco. Jose Rafael Garrido, Alvaro Camiha, Mariangela Guinda, Maria Egea, Nourdine Mouati, Alfonso Godino, and J.L. Paz de la Rocha * 70 Artificial Nest Structure Use and Reproductive Success of Barn Owls in Northeastern Arkansas. Paul M. Radley and James C. Bednarz 74 Abundance and Diet of Alexander’s Kestrel {Falco tinnvnculus alexandri) on Boavista Island (Archipelago of Cape Verde) . Diego Ontiveros 80 The Role of Thyroxine on the Production of Plumage in the American Kestrel {Falco sparverius). Michael J. Quinn, Jr., John B. French, Jr., F.M. Anne McNabb, and Mary Ann Ottinger 84 Observations of Nesting Gray-headed Kites {Leptodon cayanensis) in Southeastern Brazil. Eduardo Pio Mendes de Carvalho Filho, Gustavo Diniz Mendes de Carvalho, and Carlos Eduardo Alencar Carvalho 89 Cooperative Nesting by a Trio of Booted Eagles {Hieraaetus pennatus). Jose E. Martinez, Carlos Gonzalez, and Jose F. Calvo 92 Timing and Abundance of Migrant Raptors on Bonaire, Netheriands Antilles. Vincent Nijman, Tineke G. Prins, andJ.H. (Hans) Reuter 94 The Relationship of Foraging Habitat to the Diet of Barn Owls {Tyto alba) from Central Chile. Sabine Begall 97 Letters Iverson (2004) on Spotted Owls and Barred Owls: Comments on Methods and Conclusion. Kent B. Livezey 102 Using a Portable, Anchor-bolt Ladder to Access Rock-nesting Osprey. Tony E. Chubbs, Matthew J. Solensky, Dawn K Laing, David M. Bird, and Geoff Goodyear 103 Attempted Predation on a Large-tailed Nightjar ( Caprimulgus macrurus) by an Eastern Marsh-Harrier {Circus spilonotus) in Coastai. Vietnam. James A. Fitzsimons 106 Red-tailed Hawk Depredates Mississippi Kite Nestling at Dawn. Karl E. Miller 108 First Nesting of Cooper’s Hawks {Accipiter cooperii) in New York City Since 1955. Robert DeCandido 109 Manuscript Referees 110 provided by Arkansas State University to assist in the publication of the journal. —— THE JOURNAL OF RAPTOR RESEARCH A QUARTERLY PUBLICATION OF THE RAPTOR RESEARCH FOUNDATION, INC. VoL. 39 March 2005 No. 1 J. Raptor Res. 39(1):1-10 © 2005 The Raptor Research Foundation, Inc. THE INFLUENCE OF TIDE AND WEATHER ON PROVISIONING RATES OF CHICK-REARING BALD EAGLES IN VANCOUVER ISLAND, BRITISH COLUMBIA Kyle Hamish Elliott Canadian Wildlife Service, 5421 Robertson Road, Delta, British Columbia V4K 3N2 Canada Christopher E. Gill Simon Fraser University, 8888 University Drive, Burnaby, British Columbia V5A 1S6 Canada John E. Elliott ^ Canadian Wildlife Service, 5421 Robertson Road, Delta, British Columbia V4K 3N2 Canada Abstract. We investigated how tide and weather (temperature and rainfall) influenced Bald Eagle {Haliaeetus leucocephalus) provisioning rates on the east and west coasts of Vancouver Island, British Columbia during the 1996 breeding season. Eagles nesting on the west coast had less frequent prey- delivery rates (3.2 ± 1.0 deliveries/d, N = 6 nests) than those nesting on the east coast (7.2 ± 2.8 deliveries/d, N ~ 7 nests). Prey-delivery rates were negatively correlated with precipitation on the west coast, but not on the east coast. On both coasts, prey-delivery rates were negatively related with tem- perature (r = —0.45), as nestlings have lower energetic needs during warm weather, and positively related with adult attendance (r = 0.35). Prey-delivery rates were highest at intermediate tide height and early in the day, reflecting food availability. Intertidal fish were a major component of eagle diet on the east coast (plainfin midshipman [Porichthys notatus] = 46% by frequency) while pelagic fish were the major component on the west coast (Pacific mackerel [Scomber japonicus] = 92%). We concluded that landscape features (e.g., tidal flats) and weather (e.g., rain and temperature) interact to influence provisioning rates of Bald Eagles on Vancouver Island, and that these factors may drive spatial variation in eagle productivity. Key Words: Bald Eagle, Haliaeetus leucocephalus; British Columbia, productivity, weather, tides. LA INELUENCIA DE lA MAREA Y EL CLIMA EN LAS TASAS DE APROVISIONAMIENTO DE HAL- IAEETUS LEUCOCEPHALUS QfJE SE ENCONTRABAN CRIANDO EN VANCOUVER ISLAND, BRITISH COLUMBIA Resumen. Investigamos como la marea y el clima (temperatura y precipitaciones) influenciaron las tasas de aprovisionamiento por parte de individuos de Haliaeetus leucocephalus en las costas este y oeste de Vancouver Island, British Columbia, durante la estacion reproductiva de 1996. Las aguilas que esta- ban nidificando en la costa oeste presentaron tasas de entrega de presas menos frecuentes (3.2 ±1.0 entregas/d, N = 6 nidos) que aquellas que estaban nidificando en la costa este (7.2 ± 2.8 entregas/d, N = 7 nidos) . Las tasas de entrega de presas estuvieron negativamente correlacionadas con la precipi- tacion en la costa oeste, pero no en la costa este. En ambas costas, las tasas de entrega de presas estuvieron relacionadas negativamente con la temperatura (r = —0.45), debido a que los pichones ^ Email address: [email protected] 1 2 Elliott et al. VoL. 39, No. 1 tienen necesidades energeticas menores durante periodos calidos, y relacionadas positivamente con la presencia de los adultos (r = 0.35). Las tasas de entrega de las presas fueron mas altas a niveles inter- medios de altura de la marea y al comienzo del dia, reflejando la disponibilidad de alimentos.