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Wednesday, 17 December 2014

Wilson Journal of Ornithology, December 2014. Contents and Abstracts

The Wilson Journal of Ornithology
Published by: The Wilson Ornithological Society

Table of Contents
Dec 2014 : Volume 126 Issue 4


Long-term dynamics of bird use of clearcuts in post-fledging period

Paul A. Porneluzi, Rafael Brito-Aguilar, Richard L. Clawson, and John Faaborg
pg(s) 623–634

We focus on bird use of clearcuts resulting from even-aged management as part of the Missouri Ozark Forest Ecosystem Project (MOFEP). The long-term nature of MOFEP allows us to present a 15-year monitoring of bird use of MOFEP clearcuts in July using constant effort mist-netting. This provides insight into the dynamics of forest bird use of clearcuts during the post-fledging period for both early succession and mature forest breeding birds. We operated nets ∼10,080 hrs and captured 4,711 individuals, with 2,718 individuals considered mature forest breeding birds, and 1,993 individuals considered early succession species. There were few birds occupying clearcuts in year 1, immediately after cutting. Mean captures of all species as a group showed a significant curvilinear trend over time with an early peak in year 3 to 4 followed by decline. Mean captures of early succession species showed a significant trend of an early peak in year 3 followed by steady decline. Mature forest breeding species captures showed a significant curvilinear trend that increased gradually up to a peak around 6–9 years after harvest and then declined. Capture rates suggest that large numbers of birds use clearcuts in the decade after the clearcuts are formed. The abundance of forest-breeding birds in clearcuts in late summer equals or even exceeds the abundance of clearcut-breeding birds found there. This suggests that clearcuts may be an important habitat for mature forest breeding birds after they breed in mature habitats. More work on post-fledging behavior of migratory birds is needed to determine those species which require early succession habitats such as clearcuts and those species which simply take advantage of such habitats should they occur in the vicinity.

Abstract & References : Full Text : PDF (429 KB)

Systematics of the obligate ant-following clade of antbirds (Aves: Passeriformes: Thamnophilidae)

Morton L. Isler, Gustavo A. Bravo, and Robb T. Brumfield
pg(s) 635–648

Results of a comprehensive molecular phylogeny of the family Thamnophilidae were consistent with earlier findings that almost all obligate army-ant-followers of the family form a monophyletic group that contains five well-supported clades and encompasses six currently recognized genera:Phaenostictus, Pithys, Willisornis, Gymnopithys, Rhegmatorhina, and Phlegopsis. A comparative analysis of seven suites of morphological, behavioral, and ecological traits within the context of the phylogeny reinforced the validity of five of these genera, but results for the sixth,Gymnopithys, were internally inconsistent and required the description of a new genus, Oneillornis.

Abstract & References : Full Text : PDF (578 KB)

Canada to Tierra del Fuego: species limits and historical biogeography of the Sedge Wren (Cistothorus platensis)

Mark B. Robbins and Árpád S. Nyári
pg(s) 649–662

We examined the phylogeography of the Western Hemispheric Sedge Wren (Cistothorus platensis) which occurs in grasslands from Canada to Tierra del Fuego. Genetic data indicate that Sedge Wren is paraphyletic with Mérida (Cistothorus meridae) and Apolinar's (Cistothorus apolinari) wrens and the currently recognized Sedge Wren is composed of a minimum of eight species. Speciation within this complex appears to have accelerated with the formation of the Isthmus of Panama which enabled the ancestor to occupy and differentiate in grassland habitats from sea level to above tree line in the Andes on the South American continent. As a result of the dramatic, negative anthropogenic impact on grasslands across the entire Western Hemisphere all species have suffered substantial declines and several are now threatened.
Abstract & References : Full Text : PDF (384 KB) 

Geographic and seasonal distribution of a little-known Brazilian endemic rail (Aramides mangle) inferred from ocurrence records and ecological niche modeling Full Access

Rafael Sobral Marcondes, Glaucia Del-Rio, Marco Antonio Rego, and Luís Fábio Silveira
pg(s) 663–672

Regional, intratropical avian migrations have rarely been studied. Here, we employ an occurrence records review and ecological niche modeling tools to test the hypothesis that an understudied Neotropical bird, the Little Wood-Rail (Aramides mangle, Rallidae), seasonally migrates between the humid Atlantic coast and the dry Caatinga biome of interior northeastern Brazil. We divided records geographically between coastal and inland, and temporally between wet/breeding and dry/non-breeding seasons. Coastal records peak when inland records are fewest and vice-versa, and independence between season and region in which records were made was statistically rejected. However, ecological niche modeling shows that coastal regions are suitable habitats for A. mangle year-round, and models built with records from each season were considered statistically equivalent. It seems that this species neither performs erratic, unpredictable movements nor typical avian “to-and-fro” migration. Instead, it undergoes periodical expansion of its range and ecological niche to include the Caatinga, where it breeds, in addition to the coast. It might be counterintuitive that a species can occupy two seemingly so disparate habitats, but rails in general are known to be very adaptable and have wide ecological niches. Further study is needed in order to understand the exact nature of this species' movements and the life-cycle of individual birds. But given that most studies of avian movements have focused on temperate species, it is likely that common models of avian migratory behavior will not easily apply to A. mangle nor to other Neotropical species.
Abstract & References : Full Text : PDF (366 KB) 

Differences in bird assemblages between native natural habitats and small-scale tree plantations in the semiarid midwest of Argentina 

Full Access

Fabricio D. Cid and Enrique Caviedes-Vidal
pg(s) 673–685

We studied the effects on structure of bird assemblages after replacement of native natural habitats by small-scale tree plantations used for recreational purposes. The richness and diversity were similar among habitats; however, the total bird abundance was greater in the tree plantations compared to the natural habitats. Also, we found that small-bodied birds that forage in the foliage had higher abundance in the natural habitats, while larger-bodied species that live in open spaces and forage on the ground occurred in higher abundance in the tree plantations. The comparative evaluation of the seasonal effect on avian assemblages of the contrasting habitats showed that natural habitats had a greater annual fluctuation of abundance values, while the tree plantations were more constant. Our study demonstrates that small-scale tree plantations for recreational purposes exert strong effects on bird assemblages, because they increase the abundance of the generalist and common bird species in the region.
Abstract & References : Full Text : PDF (334 KB) 

Nesting ecology of grassland songbirds: effects of predation, parasitism, and weather 

Full Access

Sarah M. Ludlow, R. Mark Brigham, and Stephen K. Davis
pg(s) 686–699


Understanding the breeding ecology of grassland birds is vital for understanding the mechanisms underlying their widespread population declines. We describe the breeding biology of Sprague's Pipit (Anthus spragueii), Vesper Sparrow (Pooecetes gramineus), Savannah Sparrow (Passerculus sandwichensis), Baird's Sparrow (Ammodramus bairdii), and Western Meadowlark (Sturnella neglecta) and quantify the effects of nest predation, brood parasitism, and weather on the nest survival of these species in southeastern Alberta. Nest predation was the primary cause of nest failure, accounting for 75% of all nest losses. Daily survival rates were higher during incubation than the nestling stage for the three sparrow species, and nest survival of Baird's Sparrows was highest at intermediate temperatures. For all five species, clutch size, hatching success, and fledging success were within the range of values previously reported for these species in other parts of their range. Brown-headed Cowbirds parasitized nests of all species except Sprague's Pipit, with 4–11% of nests containing cowbird eggs. Savannah Sparrow experienced the highest frequency of brood parasitism and was the only species to successfully fledge cowbird young. Parasitized nests of Savannah Sparrows had reduced clutch size and hatching success, and fledged fewer young compared to non-parasitized nests. The overall cost of parasitism to Savannah Sparrows was at least 1.7 young per successful nest.
Abstract & References : Full Text : PDF (238 KB) 

Survival of Red-headed Woodpeckers' (Melanerpes erythrocephalus) nests in northern New York Full Access

Jacob L. Berl, John W. Edwards, Jeffrey S. Bolsinger, and Todd E. Katzner
pg(s) 700–707
Populations of Red-headed Woodpeckers (Melanerpes erythrocephalus) have declined throughout much of their range. Conservation management to arrest declines or increase populations is difficult, because many aspects of the species' demography remain poorly understood. To address this knowledge gap, we monitored Red-headed Woodpeckers' nests on Fort Drum Military Installation, in northern New York and modeled daily nest survival rate as a function of temporal and habitat-specific covariates. Red-headed Woodpeckers had low overall nest survival rates (nest survival  =  32%), and predation was the leading cause (82%) of nest failure. Cavity concealment had the greatest influence on daily nest survival rate, whereby nests with greater vegetative structure surrounding (within 1 m2 of) the nest cavity had higher survival rates, likely because of reduced nest predation. Our estimates of Red-headed Woodpeckers' nest survival were lower relative to other portions of their range and suggest that, at local scales, low reproductive rates near the periphery of the species' distribution may limit population growth.
Abstract & References : Full Text : PDF (176 KB) 

Agonistic behaviors between Chestnut-sided (Setophaga pensylvanica) and Golden-winged (Vermivora chrysoptera) warblers are unlikely a result of plumage misidentification Full Access

John A. Jones and Lynn Siefferman
pg(s) 708–716


Plumage coloration within species is often a signal of competitive ability and can influence territorial aggression between males. Agonistic interactions among males of different co-occurring species could result from misidentification (misdirected conspecific aggression). Reflectance spectrometry of plumage coupled with models of avian vision can be used to infer whether plumage color differences can be distinguished by birds. Here we investigate crown coloration similarity as a potential explanation for aggression between the imperiled Golden-winged Warbler (Vermivora chrysoptera) and the comparatively abundant Chestnut-sided Warbler (Setophaga pensylvanica). Because the yellow crown coloration of the two species appears identical to humans, we hypothesized that misidentification of heterospecifics as conspecifics could escalate agonistic interactions. Using museum study skins, we tested whether the yellow crown coloration of the two species should be distinguishable to the birds. Spectral reflectance data demonstrate that plumage color differs between the two species and avian vision models suggest these color differences should be easily discriminated. Thus, we conclude that plumage coloration similarity between these wood warblers is unlikely to cause misidentification of heterospecifics as conspecifics and may just be a result of phylogenic constraint. As populations of Golden-winged Warblers are experiencing accelerating declines, research focusing on the role interspecific competition plays on reduced productivity and survival is warranted.
Abstract & References : Full Text : PDF (298 KB) 

Breeding biology of the Spotted Barbtail (Premnoplex brunnescens) 

Daniel Muñoz and Thomas E. Martin
pg(s) 717–727


The Spotted Barbtail (Furnariidae) is poorly studied but shows some extreme traits for a tropical passerine. We located and monitored 155 nests to study this species for 7 years in an Andean cloud forest in Venezuela. Spotted Barbtails have an unusually long incubation period of 27.2 ± 0.16 days, as a result of very long (3–6 hr) off-bouts even though both adults incubate. The long off-bouts yield low incubation temperatures for embryos and are associated with proportionally large eggs (21% of adult mass). They also have a long nestling period of 21.67 ± 0.33 days, and a typical tropical brood size of two. The slow growth rate of the typical broods of two is even slower in broods artificially reduced to one young. Nonetheless, the young stay in the nest long enough to achieve wing lengths that approach adult size.
Abstract & References : Full Text : PDF (833 KB) 

Habitat and food preferences of the endangered Palila (Loxioides bailleui) on Mauna Kea, Hawai‘i Full Access

Steven C. Hess, Paul C. Banko, Linda J. Miller, and Leona P. Laniawe
pg(s) 728–738

Seeds and flowers of the leguminous māmane (Sophora chrysophylla) tree are the primary food resource of the federally endangered Palila (Loxioides bailleui; Fringillidae: Drepanidinae), which is now restricted to dry subalpine woodland on Mauna Kea Volcano on the island of Hawai‘i because of centuries of habitat degradation by non-native ungulates. Palila are morphologically and behaviorally adapted to consume māmane seeds by grasping seed pods with their feet and opening pods with stout bills and demonstrate limited ability to exploit alternative food resources. This degree of single species dependency is rare among birds and illustrates unique adaptations that also occurred in other Hawaiian species that are now extinct. In mixed-woodland with co-dominant naio (Myoporum sandwicense), Palila spent 1.7–3.9 times longer in māmane than in naio during foraging observations where naio was 1.3–4.6 times as dense as māmane. Naio fruit was readily available, but it comprised proportionally <11% of food items taken by Palila. Although māmane flowers were more abundant than māmane pods throughout this study except at one lower-elevation mixed-woodland site, Palila spent more time foraging on pods than flowers in both māmane woodland and mixed-woodland, but consumed more flowers than pods in mixed-woodland. Insects, which have been reported as an important component of the diet of Palila, were apparently taken rarely in this study. Protecting and restoring māmane in woodlands adjacent to the current range of Palila will benefit their recovery, allowing them to exploit increased food availability in areas of their former range.
Abstract & References : Full Text : PDF (340 KB) 

Leg abnormalities and leucocyte profiles in the European Storm-Petrel (Hydrobates p. pelagicus) from the Faroe Islands Full Access

Katarzyna Wojczulanis-Jakubas, Dariusz Jakubas, Anna Kośmicka, and Jens-Kjeld Jensen
pg(s) 739–745
Although abnormal or injured legs are not uncommon in Hydrobatidae, they are rarely investigated. We aimed in this study to estimate the frequency of leg abnormalities and determine health status (expressed by leucocyte profile) in molecularly sexed European Storm-Petrels (Hydrobates p. pelagicus) captured on the Faroe Islands. We found that 2.4% of individuals captured during the breding season had some leg abnormalities. Half of the birds with abnormalities had puffinosis-like changes, while the rest were missing some part of the leg. Both types of abnormalities were recorded in the two sexes with similar frequency. The proportion of the birds with leg abnormalities seems to be relatively low compared to other Procellariiformes, and stable over time. Despite the apparent disability of the birds with leg abnormalities, we found no significant effect of abnormality status on the leucocyte profile.
Abstract & References : Full Text : PDF (162 KB) 

Prevalence of haematozoa in migrating Northern Saw-Whet Owls (Aegolius acadicus) of eastern North America Full Access

Emma I. Young and Glenn A. Proudfoot
pg(s) 746–753

We examined blood smears from 139 Northern Saw-whet Owls (Aegolius acadicus) to ascertain the prevalence of haematozoa in this species during fall migration in eastern North America. Owls were captured with mist nets on the Mohonk Preserve near New Paltz, New York from 1 October to 2 December 2011. We examined blood smears under an optical microscope at 200× and 1000× magnification, and observed four genera of haematozoa, HaemoproteusLeucocytozoonPlasmodium, and Trypanosoma, in addition to a genus or genera of microfilarial nematodes, unidentifiable by morphology. We found haematozoa in blood smears from both male and female Northern Saw-whet Owls and in both age groups sampled, i.e., hatching year and after hatching year. Leucocytozoon was the most common parasite, with an overall prevalence of 49.6%. Prevalence of Haemoproteus, microfilaria, Plasmodium, and Trypanosoma was 5.0%, 5.0%, 10.0%, and 2.9% respectively, and overall occurrence of infection was 64%. We found no difference in body condition of individuals compared by age, infection status, or intensity of infection. To our knowledge, this is the first record of Plasmodium in Northern Saw-whet Owls, and the first study to document five genera of haematozoa in Northern Saw-whet Owls during fall migration. Revealing new host–parasite information, this study contributes to the information portfolio of Northern Saw-whet Owls and, thus, may influence future research.
Abstract & References : Full Text : PDF (257 KB) 


Diet of Nestling Spectacled Tyrants (Hymenops perspicillatus) in the Southeast Pampas Region, Argentina Full Access

Matías G. Pretelli, Daniel A. Cardoni, and Juan P. Isacch
pg(s) 754–759

We studied the diet of nestling Spectacled Tyrants (Hymenops perspicillatus) in the southeast Pampas region, Argentina. From November 2012 to January 2013, we used video footage to determine prey items that the parents fed to their chicks. We obtained 54 hrs of recording time to survey 18 nests. We identified a total of 125 prey items, representing 33 different taxa, grouped into four classes: Insecta, Arachnida, Chilopoda, and Amphibia. Insects accounted for 94% of total prey. The most frequent prey items were orthopterans (Caelifera), unidentified lepidopteran larvae, and odonats (Zygoptera). Lepidopterans were numerically the most important prey item in November, odonats in December, and orthopterans in January. Diet of the nestling birds was generalist in terms of the consumption of insects, and the changes in prey consumption during the course of the breeding season support an opportunistic feeding behavior by Spectacled Tyrants.
Abstract & References : Full Text : PDF (209 KB) 

Relative Abundance of Parrots throughout the Yucatan Peninsula: Implications for their Conservation Full Access

Alexis Herminio Plasencia-Vázquez and Griselda Escalona-Segura
pg(s) 759–766

Information on species' abundances of members of the Family Psittacidae (parrots) is scarce. We determined relative abundances of parrots in nine areas of the Yucatan Peninsula; six sampled during the years 2011–2012, and three during 2008–2010. We counted parrots on 360 plots, calculated relative abundance, and constructed dominance - diversity graphs. Six species were identified in the study areas: Amazona albifrons,Eupsittula nanaAmazona xantholoraAmazona autumnalisAmazona oratrix and Pionus senilis. The southern Yucatan Peninsula harbored the highest number of species. Overall, E. nana was the most abundant species, although in the southern portion of the peninsula A. albifrons was dominant. Using the abundance values obtained in this research, we can begin to identify and establish new priority sites for parrot conservation within the Yucatan Peninsula and develop new proposals for conservation and sustainable management practices in the region.
Abstract & References : Full Text : PDF (166 KB) 

Multiple Broods and Nest Success in Western Yellow-breasted Chats (Icteria virens auricollis) in the south Okanagan Valley, British Columbia, Canada Full Access

René McKibbin and Christine A. Bishop
pg(s) 767–771

During 2005–2010, we observed color bands on adult birds to discover one instance of triple brooding and multiple cases of double brooding in western Yellow-breasted Chats (Icteria virens auricollis) in the south Okanagan Valley, British Columbia (BC), Canada at the northern periphery of their breeding range. In the case of the triple brood, the first and second broods successfully fledged chats but the third brood failed. During the same period, 4.7% of banded females had double broods. Another 32 unidentified females for whom we are confident were the same females who initiated the first brood, also had double broods. If these females are included, 13% of chats had double broods. During 2002–2010, 57.8% first brood nests were successful and during 2005–2010, 69.2% second brood nests were successful.

Predation of Small-bodied Mammals (Callithrix and Kerodon) by Laughing Falcons (Herpetotheres cachinnans) in the semi-arid Caatinga Scrub Forest of the Brazilian Northeast Full Access

Tacyana D. Amora and Stephen F. Ferrari
pg(s) 771–775

Laughing Falcons (Herpetotheres cachinnans), are known to feed primarily on snakes, although there are reports in the literature of the falcons feeding on other prey. In the present study in the semi-arid scrublands of the Brazilian Caatinga, two predation events were recorded in which Laughing Falcons captured small-bodied mammals, a marmoset (Callithrix jacchus) and a rock cavy (Kerodon rupestris), both estimated to be approximately 200–300 g in weight. In both cases, the mammals were juveniles; the falcon swooped down to capture the prey in its talons, then it flew off to feed some distance away. While these events suggest a shift in the feeding niche of the falcon in response to local conditions, the number of observations is too small to permit definitive conclusions on this phenomenon.

Site Fidelity, Residency, and Sex Ratios of Wintering Ruby-throated Hummingbirds (Archilochus colubris) on the southeastern U.S. Atlantic Coast Full Access

Doreen Cubie
pg(s) 775–778

Ruby-throated Hummingbirds (Archilochus colubris) are common and widespread but little is known about their winter ecology anywhere within their nonbreeding range, and no studies have been conducted on the individuals that now overwinter along the southeastern Atlantic coast of the United States. From 2008–2012, I examined the winter survivability, site fidelity, residency, and age and sex ratios of Ruby-throated Hummingbirds at one location in coastal South Carolina. I investigated whether the wintering population there was migratory or sedentary. Winter site fidelity was 19.4% overall (14.6% for males and 31.6% for females), which is similar to or higher than return rates found in studies near the Gulf of Mexico coast, 300 km to the south. The rate of winter residency was 26.3%. Juvenile sex ratios were significantly male biased, suggesting possible latitudinal sexual segregation, although more study is needed. Only one bird banded during spring, summer, or fall was recaptured during the winter, indicating a probable turnover of birds between summer and winter.
Abstract & References : Full Text : PDF (55 KB) 

Observations of a Bilateral Gynandromorph Northern Cardinal (Cardinalis cardinalis) Full Access

Brian D. Peer and Robert W. Motz
pg(s) 778–781

We describe behavioral observations of a bilateral gynandromorph Northern Cardinal (Cardinalis cardinalis) in northwestern Illinois from December 2008 through March 2010. The bird exhibited the typical bright red color of a male cardinal on the left half of its body, and the dull brownish-gray appearance of a female cardinal on the right half. We observed the bird more than 40 days, mostly in the vicinity of bird feeders. It was never paired with another cardinal, was never heard vocalizing, and was not subjected to any unusual agonistic behaviors from other cardinals. These observations are among the most extensive of any bilateral gynandromorph bird in the wild.
Abstract & References : Full Text : PDF (420 KB) 

Tuesday, 16 December 2014

Multilocus assessment of sparrow relationships. Klicka et al 2014

A comprehensive multilocus assessment of sparrow (Aves: Passerellidae) relationships

Molecular Phylogenetics and Evolution
Volume 77, August 2014, Pages 177–182

LINK to pdf


John Klicka, a
F. Keith Barker, b, c
Kevin J. Burns, d
Scott M. Lanyon, b
Irby J. Lovette, e
Jaime A. Chaves, f, g
Robert W. Bryson Jr., a

a  Department of Biology and Burke Museum of Natural History and Culture, University of Washington, Box 353010, Seattle, WA 98195-3010, USA
b  Department of Ecology, Evolution, and Behavior, University of Minnesota, 100 Ecology Building, 1987 Upper Buford Circle, St. Paul, MN 55108, USA
c  Bell Museum of Natural History, University of Minnesota, 100 Ecology Building, 1987 Upper Buford Circle, St. Paul, MN 55108, USA
d  Department of Biology, San Diego State University, San Diego, CA 92182, USA
e  Fuller Evolutionary Biology Program, Cornell Lab of Ornithology, Cornell University, 159 Sapsucker Woods Road, Ithaca, NY 14950, USA
f  Department of Biology, University of Miami, 1301 Memorial Drive, Coral Gables, FL 33146, USA
g  Universidad San Francisco de Quito, USFQ, Colegio de Ciencias Biológicas y Ambientales, y Extensión Galápagos, Campus Cumbayá, Casilla Postal 17-1200-841, Quito, Ecuador

  Multilocus reconstruction of phylogeny of the sparrow family Passerellidae.
  Sparrow diversity is defined predominantly by eight well-supported clades.
  Three currently recognized genera are polyphyletic.

The New World sparrows (Emberizidae) are among the best known of songbird groups and have long-been recognized as one of the prominent components of the New World nine-primaried oscine assemblage. Despite receiving much attention from taxonomists over the years, and only recently using molecular methods, was a “core” sparrow clade established allowing the reconstruction of a phylogenetic hypothesis that includes the full sampling of sparrow species diversity. In this paper, we use mitochondrial DNA gene sequences from all 129 putative species of sparrow and four additional (nuclear) loci for a subset of these taxa to resolve both generic and species level relationships. Hypotheses derived from our mitochondrial (2184 base pairs) and nuclear (5705 base pairs) DNA data sets were generally in agreement with respect to clade constituency but differed somewhat with respect to among-clade relationships. Sparrow diversity is defined predominantly by eight well-supported clades that indicate a lack of monophyly for at least three currently recognized genera. Ammodramus is polyphyletic and requires the naming of two additional genera. Spizella is also polyphyletic with Tree Sparrow (Spizella arborea) as a taxonomic “outlier”. Pselliophorus is embedded within a larger Atlapetes assemblage and should be merged with that group. This new hypothesis of sparrow relationships will form the basis for future comparative analyses of variation within songbirds.

Graphical Abstract

Journal of Raptor Research - Osprey Special. December 2014: Volume 48 Issue 4, Table of Contents and Abstracts

Journal of Raptor Research

Published by: The Raptor Research Foundation

Table of Contents

Dec 2014 : Volume 48 Issue 4 

Ospreys (Pandion haliaetus) in the 21st Century: Populations, Migration, Management, and Research Priorities 

Richard O. Bierregaard, Alan F. Poole, and Brian E. Washburn
pg(s) 301–308
 Full Text : PDF (80 KB) 
Ospreys (Pandion haliaetus) are remarkable raptors. Their choice of conspicuous nest sites and surprising tolerance for nesting in nearly intimate association with humans render them an iconic piece of aquatic ecosystems in both marine and freshwater habitats across the northern hemisphere and much of Australasia (Australia to Indonesia). Wintering in Central and South America and Africa as well, they are among the few truly cosmopolitan birds of prey.
Ecologically, they might be termed generalized specialists. They are, with exceptions so rare that they can safely be ignored, obligate fish eaters. From their talons to the tip of their bill, every bit of an Osprey's morphology is adapted to taking fish from the water and consuming them efficiently. Beyond this specialization, however, they are remarkably catholic in the species of fish that they prey on (Poole et al. 2002). Inland, the predominant fish species caught vary from watershed to watershed. Along the coasts, the fish brought to the nest will change through the breeding season as different prey species migrate in and out of the hunting range of local populations.
Most notably, because they are perched atop a long food chain, they are vulnerable to, and dramatic indicators of fat-soluble contaminants in the environment. In the 1960s and 1970s this led the species to play a pivotal role in the identification of DDT as a major threat to aquatic ecosystems and the banning of its use in the U.S.

The Spring Migration of Adult North American Ospreys Full Access

Mark S. Martell, Richard O. Bierregaard, Jr., Brian E. Washburn, John E. Elliott, Charles J. Henny, Robert S. Kennedy, and Iain MacLeod
pg(s) 309–324

 Full Text : PDF (438 KB) 
Most North American Ospreys (Pandion haliaetus) are migratory, breeding in northern latitudes and migrating long distances to and from their wintering grounds in the tropics. Although fall migration patterns of North American Ospreys have been described and studied, very little has been published about the spring migration of these birds. We used satellite telemetry to: (1) determine the characteristics (timing, duration, migratory routes) of spring migrations of Ospreys; (2) determine if differences in spring migration patterns existed between sexes and among three breeding populations (east coast, midwestern, and western); and (3) compare consecutive fall and spring migrations of individual Ospreys. The median dates for departure from the wintering grounds and arrival on the breeding grounds did not differ significantly between adult male and female Ospreys. Compared to their fall migrations, all male and all east coast Ospreys spent fewer days on migration, fewer days in stopover periods along the migration route, traveled shorter distances overall, and traveled farther (on average) each day during spring. In contrast, fall and spring migration characteristics of all female and western Ospreys were similar. Our findings suggest that, although sex and breeding location might influence the spring migration strategy used by individual Ospreys, both males and females minimize the time spent on migration to ensure a timely arrival on the breeding grounds to establish or defend a nesting territory.

Wintering Ecology of Adult North American Ospreys Full Access

Brian E. Washburn, Mark S. Martell, Richard O. Bierregaard, Jr., Charles J. Henny, Brian S. Dorr, and Thomas J. Olexa
pg(s) 325–333

 Full Text : PDF (191 KB)
North American Ospreys (Pandion haliaetus) typically migrate long distances to their wintering grounds in the tropics. Beyond the general distribution of their wintering range (i.e., the Caribbean, South America, and Central America), very little is known about the wintering ecology of these birds. We used satellite telemetry to determine the duration of wintering period, to examine the characteristics of wintering areas used by Ospreys, and to quantify space use and activity patterns of wintering Ospreys. Adult Ospreys migrated to wintering sites and exhibited high wintering site fidelity among years. Overall, Ospreys wintered on river systems (50.6%) more than on lakes (19.0%), and use of coastal areas was (30.4%) intermediate. Ospreys remained on their wintering grounds for an average of 154 d for males and 167 d for females. Locations of wintering Ospreys obtained via GPS-capable satellite telemetry suggest these birds move infrequently and their movements are very localized (i.e., <5 km from selected roosting areas). Sizes of home ranges and core-use areas for wintering Ospreys averaged 12.7 km2 and 1.4 km2, respectively. Overall, our findings suggest wintering adult North American Ospreys are very sedentary, demonstrating a pattern of limited daily movements and high fidelity to a few select locations (presumably roosts). We suggest this wintering strategy might be effective for reducing the risk of mortality and maximizing energy conservation.

Magnitude and Timing of Autumn Osprey Migration in Southeastern Cuba Full Access

Freddy Rodríguez-Santana, Yasit Segovia Vega, Malbelis Sánchez Padilla, Carmen Plasencia León, Yasser E. Torres Adán, Margarita Sánchez Losada, Arelis Mustelier Lescay, and Yaquelín Rivera
pg(s) 334–344

 Full Text : PDF (298 KB)
From 2005–2008 we used counts of visible migrants at an inland watchsite (La Gran Piedra) 9 km from the coast and a coastal watchsite (Siboney) to describe the magnitude and timing of Osprey (Pandion haliaetus) autumn migration through southeastern Cuba from 1 August through 30 November. Counts of Ospreys at Siboney averaged 5283 (2006–2008) annually or roughly twice those tallied at other North American watchsites known for the concentration of this species during autumn migration. Nevertheless, simultaneous counts at both watchsites better represent the magnitude of its migration through southeastern Cuba, averaging more than 7000 Ospreys (3 yr). The mean seasonal passage window (95% of the flight) ranged from 78 to 83 d at La Gran Piedra and Siboney. The average peak at both sites occurred in early October, with more than 20 Ospreys/hr. The daily passage window (95% of the daily passage) was more protracted at Siboney, where birds migrated both early in the morning and late in the afternoon, than at the inland mountain site at La Gran Piedra, where Osprey numbers peaked at midday. We believe that Ospreys migrating in southeastern Cuba move from the coast to the mountains at midday in response to thermal convections along the mountains at that time. Osprey flocks observed at watchsites ranged between 2–52 individuals and one flock of 92 individuals was observed at a dam in central Cuba.

Wintering of Ospreys in Argentina: Insights From New Records Between 1993–2008 Full Access

Miguel D. Saggese, Ignacio Roesler, and Claudia F. Marano
pg(s) 345–360

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The migratory subspecies of the “American” Osprey (Pandion haliaetus carolinensis) breeds across most of North America. Most of these Ospreys winter north of the equator, although significant numbers travel farther south, reaching Argentina. The number of Osprey sightings in Argentina has increased since the first review of their status in this country. We analyzed records of Osprey migration and distribution in Argentina from 1993 to 2008. We found that Ospreys occur year-round in Argentina, with a higher concentration in spring to summer (1 October to 31 March). Our data confirmed that in northern and northeastern Argentina, Ospreys use river systems and their major tributaries, and in central and northwestern regions, they commonly frequent reservoirs. The apparent increase in the number of Osprey records in Argentina in the last decades may result from an actual population increase but may also reflect a larger number of observers. Recent records suggest that Osprey should be considered a regular visitor to northern Argentina. We confirm the importance of northeastern rivers, and central and northwestern reservoirs as wintering areas. Argentina has been noted as an important wintering area for many migratory birds, but has been underestimated as a wintering area for Osprey.

Post-DDT Recovery of Osprey (Pandion haliaetus) Populations in Southern New England and Long Island, New York, 1970–2013 Full Access

Richard O. Bierregaard, Jr., Augustus Ben David, Lori Gibson, Robert S. Kennedy, Alan F. Poole, Michael S. Scheibel, and Julie Victoria
pg(s) 361–374

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The Osprey (Pandion haliaetus) population nesting between New York City and Boston, Massachusetts, collapsed from approximately 1000 pairs in 1940 to 109 in the early 1970s. In the 1970s, within five or six years of the cessation of DDT use in the region, the Osprey population began recovering. The recovery was asynchronous across the region. Current (2013) distribution and numbers differ dramatically from those of the pre-DDT period. Colonies on Narragansett and Mount Hope bays in Rhode Island, the Connecticut River estuary, and on Gardiners Island, New York, failed to recover their former remarkable densities. Osprey populations expanded from eastern to western Long Island, New York. In Connecticut, Ospreys now occupy the entire coastline and are nesting inland. A new concentration of Ospreys has become established in southeastern Massachusetts on the Westport River, the islands of Martha's Vineyard and Nantucket, and most recently, on Cape Cod. From this area, the species' range has gradually expanded northward. The population in Massachusetts is now contiguous with the New Hampshire population, and pairs are nesting west of the Connecticut River. The current population in southern New England easily exceeds 1200 pairs and is predominantly (ca. 95%) nesting on human-made structures either erected as nest platforms or co-opted by Ospreys as nest support structures.

The Osprey in the Western Palearctic: Breeding Population Size and Trends in the Early 21st Century Full Access

Daniel Schmidt-Rothmund, Roy Dennis, Pertti Saurola
pg(s) 375–386

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The number of Osprey (Pandion haliaetus) nesting pairs in Europe, northern Africa, and the Middle East has reached between 9500 and 11 500 in the early 21st century. Compared to numbers from the 1980s (ca. 5500 pairs), the population has almost doubled. The increase is most obvious in countries like Germany and the United Kingdom. The largest and most important European populations in Sweden, Finland, and Russia seem to be stable. In contrast, Portugal, mainland Spain, and Turkey lost their last breeding pairs in the 1980s and 1990s. Negative trends are also reported from Poland due to persecution and from southeastern Europe and northern Africa, where only very few pairs remain. Reintroductions in England, Spain, and Italy have resulted in a few new breeding pairs in recent years.

Human–Osprey Conflicts: Industry, Utilities, Communication, and Transportation Full Access

Brian E. Washburn
pg(s) 387–395

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Although often perceived as a species of remote settings, Ospreys (Pandion haliaetus) are highly adaptable and currently are abundant in many urban and suburban landscapes. Living in close proximity to humans, Ospreys often come into conflict with people and several important issues require the attention of and management by natural resource professionals. These include effects on: (1) industry (e.g., foraging at aquaculture facilities), (2) utilities (e.g., nesting on electric utility power poles and transmission towers), (3) communication networks (e.g., nesting on cellular towers), and (4) transportation systems (e.g., risks posed to human health and safety due to Osprey–aircraft collisions). Due to the Osprey's migratory and wintering habits, conflicts between Ospreys and humans are generally seasonal in nature (i.e., during the nesting season); Florida is an important exception. Creative mitigation measures (many currently being developed and evaluated) that combine effective management and monitoring will provide a better understanding of human–Osprey conflicts and ensure our successful coexistence with Osprey populations in the future.


Distribution and Natural History of the Caribbean Osprey (Pandion haliaetus ridgwayi) Full Access

James W. Wiley, Alan F. Poole, and Nancy J. Clum
pg(s) 396–407

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Pandion haliaetus ridgwayi is a subspecies that breeds in the Caribbean basin on which little is known. We present an overview of the status and distribution of this subspecies, with emphasis on the delineation of areas of concentration of nesting and providing brief notes on its natural history. Overall P. h. ridgwayi is distributed and dispersed in limited numbers with documented nesting in the south of the Bahamas, Turks and Caicos, and along the coasts of Cuba, Yucatan in Mexico and Belize. Coastal areas are home to the only known breeding pairs, which build their nests in a variety of natural structures and increasingly frequently in artificial structures. Most couples put their eggs in November and December and generally chicks leave the nest in February and March. Limited data suggest that reproductive rates are low compared to those of individuals of P. haliaetus nesting in more temperate latitudes. We recommend renewed for the census of this species, especially in regions where nests can be grouped together and discuss the potential for increasing key populations with artificial nesting platforms for efforts.

The Status of the Osprey (Pandion haliaetus cristatus) in Australia Full Access

Terry E. Dennis and Greg P. Clancy
pg(s) 408–414

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In Australia, most Australasian populations Pandion haliaetus cristatus found in coastal and estuarine habitats along the subtropical and temperate regions of the north. On the lines south coast, the species is distributed more dispersed mode and there is a wide gap in the breeding range in the southeastern corner of the continent below 36 ° south latitude, including Tasmania. The population is mainly sedentary and is considered as stable throughout most of its range. However, there are reports that the population is decreasing at the southern edge of its range in southern Australia, but growing and expanding its breeding range area south into New South Wales. Reproductive rates and population densities for expanding populations on the east coast are equivalent to those reported for populations recovering from P. haliaetusafter declines caused by pesticides in the northern hemisphere. Conversely, the population density is significantly lower in southern Australia where comparatively low productivity more geographic isolation suggest that P. haliaetus could be at risk in the southern end of their breeding range in Australia.

Exploring the Role of Ospreys in Education Full Access

Rebecca Cushing and Brian E. Washburn
pg(s) 414–421

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Pandion haliaetus , a charismatic species of bird of prey with an almost worldwide distribution, is highly visible and adapted to anthropic environments. Consequently, this species has been extensively studied over most of its range and provides an excellent focus for student learning in primary and secondary education. Recent advances in technology (eg, satellite telemetry, web cameras) used to study P. haliaetus have produced large databases that can be used in a variety of courses in secondary and post-secondary to facilitate the development of critical thinking, problem solving and quantitative over a wide range of geographical and political boundaries skills. The effective use of social media could improve the opportunities to integrate scientific research of P. haliaetus environmental education, scope and citizen science projects. This report describes the use of P. haliaetus in educational programs, particularly in the context of primary education. We further suggest how new technologies and research activities with P. haliaetus (and other migratory birds) can be integrated into educational programs at different levels to improve learning from experience and potentially increase the attitudes and activities for conservation.


'Enter the Realm of the Golden Eagle'

Matthew C. Perry
pg(s) 422–423
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Enter the Realm of the Golden Eagle is not just a book on the Golden Eagle, but a classic treatise that every raptor specialist will cherish as part of their library. It is very different from any other natural history book because its foundation is good old-fashioned professional biology written in a beautiful and exciting way that makes it great reading as well as an excellent reference on this noble species. The title not only reflects the species of interest, but also reflects that the reader will enter the world of the Golden Eagle from afar and at close range while seemingly with the author.
The book is large format (8.5″ × 11″) with over 400 mostly color images by 15 artists and 21 photographers. There are 18 chapters starting with “The Allure of the Eagle” and ending with “Lothvar's Gifts.” Chapter 1 is available for review at the Hancock House website: The final chapter describes the personal gifts given to Ellis from a long-time captive Golden Eagle, Lothvar, and the sometimes emotional relationship between this eagle and the author. Each chapter has from 3 to 10 subchapters. Discussions include wolf-hunting by eagles, driving huge animals over cliffs, cooperative hunting with coyotes, and how biologists capture eagles by pouncing on them during day and night.
Many of the subchapters are written by colleagues of Ellis from many countries, and reflect his worldwide exposure to this species, and his relationships with other experts. Ellis writes tributes to some of the pioneers who influenced him, using quotes from their writings. An appendix includes all the scientific names of vertebrates, invertebrates, and plants mentioned in the text. A detailed index provides easy access to the many subjects and persons that will be of value for future reference. Many of the chapters have extensive references for documentation and further study by the reader.
Some of the chapters deal with details of the eagle as a uniquely predatory bird. The detailed descriptions of three-inch talons digging deeply into wrists and thighs of the human bander or handler might be hard reading for a modern-day “couch potato” who doesn't look deeper into a predatory bird's lifestyle. Ellis' personal ethics for interacting with wildlife are passed on to the reader in a subtle, but sometimes very direct manner. He mentions John James Audubon's “wanton rapaciousness” in killing birds and actually eating eagle flesh, but then quickly reminds us how different Audubon's time was from the present, when we have our own serious conservation issues.
Ellis is in a class by himself as a student of raptor biology with a lifelong interest in Golden Eagles. His perspective on eagle behavior comes from thousands of hours in blinds in close proximity to eagle nests. He not only worked professionally in the United States as an eagle biologist, but also travelled the world to study the golden and other eagles on terrain and in conditions that few could endure. Ellis was for many years a crane researcher with the U.S. Fish and Wildlife Service and the U.S. Geological Survey, but managed surreptitiously to use his own captive eagle to incubate and hatch crane eggs.
Ellis earned his Ph.D. in Behavioral Ecology at the University of Montana and has over 200 scientific publications on numerous subjects. He is author and/or editor of several books. His wife Cathy was an important partner in the research and publication of this eagle book for the last 17 yr. Ellis dedicated the book to Cathy and gave special recognition of her contributions in the acknowledgments. Cathy is an author in her own right and has published widely in the scientific and popular literature.
This book is a compilation of the personal exploits of Ellis and those of other raptor enthusiasts in many countries, including Scotland, Russia, Mongolia, and Japan. Traditions with eagles in many countries go back thousands of years. Details given in the book open a window to many other areas and help us realize the wide array of fields (e.g., falconry, folklore, mythology, history, etc.) in which eagles, especially Golden Eagles, played important roles. Although Ellis is interested in the past research, he has included in this epic book discussions of the most recent techniques of behavioral ecology and satellite tracking to study these magnificent raptors.
Although the hardbound version sells for $60.00, some may be interested in the deluxe, collector's edition available for $300 plus shipping. This book is limited to 50 signed and numbered copies and includes a leather binding and slipcase. However, it becomes a deluxe edition because (1) the spine has five horizontal ridges beneath the leather, used to simulate the bundles of thread that in medieval times were used to sew signatures together, (2) a hand-painted eagle feather on the spine, (3) the slip-case bound in bonded leather, (4) an original watercolor painting of an eagle's head that accompanies each copy (and is removable for framing), (5) the pages are gilt-edged, and (6) an “eagle in flight” medallion of fine pewter plated with copper, then nickel, then gold, is embossed into the leather cover of the book. The medallion was sculpted by the noted artist, Mark Rossi, especially for the book. Because of the painted feather and the painted eagle head (both by Dr. Ellis), each numbered copy will be unique.
I recommend this book highly to persons fascinated with raptors or in the work of those who professionally study raptors. It is one of the most interesting I have ever read.