Search Results
Results 101 - 150 of 276
1 2 3 4 5 6 >
Nuku, Kerri - - 2012
William, Liz - - 2012
Nesdale, Tess - - 2012
Fairley, Nigel - - 2012
Hillery, Emily - - 2012
Annals, Geoff - - 2012
Braun, Clait - - 2012
Werner, Jacob - - 2012
Marks, Jeffrey - - 2012
Paul, Ellen - - 2012
Gayk, Zach - - 2012
We examined differences in microhabitat use between Boreal (Poecile hudsonicus) and Black-capped chickadees (P. atricapillus) where they co-occur near Marquette, Michigan, USA. Twenty-four Boreal and 37 Black-capped chickadees were followed during 60 hrs of field observation. Boreal Chickadees foraged only in three conifer species, 76% of which were black spruce ...
Tumlison, Renn - - 2012
Red-tailed Hawks (Buteo jamaicensis) usually hunt from a perch and swoop down on prey. I observed a novel foraging strategy in which the bird deliberately, and successfully, attacked and deconstructed nests of squirrels to flush or capture prey in an urban environment.
Stevens, Thomas - - 2012
The Tody Motmot (Hylomanes momotula) has a fragmented range throughout Central America. I present evidence from audio recordings for a new location for this species in Costa Rica. Individuals detected likely represent a previously undiscovered population in the foothills of the Caribbean Slope of the Tilaran Mountains. A small population ...
Slager, David - - 2012
We report observations of Thickbilled Euphonias (Euphonia laniirostris) and a Golden-faced Tyrannulet (Zimmerius chrysops) kleptoparasitizing nest material from Red-faced Spinetail (Cranioleuca erythrops) nests in Antioquia, Colombia. Thick-billed Euphonias (12 [+ or -] 1 m, n = 11 encounters) and Golden-faced Tyrannulets (10 [+ or -] I m, n = 19) ...
Millican, David - - 2012
Inter- and intra-specific competition are known to influence feeding decisions, but relatively little research has investigated how inter- and intrasexual interactions can impact foraging. We studied foraging preferences of male and female Northern Cardinals (Cardinalis cardinalis) during winter and found they preferred sunflower seed to safflower seed when presented with ...
Wheeler, Hazel - - 2012
Previous Chimney Swift (Chaetura pelagica) trapping efforts relied on chimney-top box traps at large roost sites, which were disruptive and inefficient when targeting individual birds. I designed a hoop net for use at nest chimneys to trap individual breeding birds. I caught 13 swifts at 11 different sites in Guelph, ...
Gunn, Carolyn - - 2012
The ecological nesting requirements of Northern Black Swifts (Cypseloides niger borealis) have been well documented, but little information exists regarding the microclimate at Black Swift nests. We placed 42 data loggers at 10 occupied Black Swift colonies between 2006 and 2010 to measure and record temperature and relative humidity, resulting ...
Kramer, Gunnar - - 2012
Relocation by dependent young is a survival strategy that occurs among a wide range of taxa. The Common Nighthawk (Chordeiles minor) lays its eggs on bare substrate and, once hatched, nestlings may relocate to new sites daily. We located and monitored eight Common Nighthawk nests in Grand Teton National Park, ...
Smith, Kayley - - 2012
Hematocrit, the percentage of packed red blood cells in blood, has been used as a measure of avian condition. We investigated the relationship between hematocrit and condition in a wild, breeding population of adult European Starlings (Sturnus vulgaris), and their nestlings (at 5- and 11-days post hatch). Hematocrit was not ...
Dykstra, Cheryl - - 2012
We examined nestling Red-shouldered Hawks (Buteo lineatus) in 56 nests ( 147 nestlings) in suburban southwestern Ohio and in 25 nests (67 nestlings) in rural forested Hocking Hills in south-central Ohio, ~180 km east of southwestern Ohio. Fifteen of 25 nests in Hocking Hills had Protocalliphora avium larvae on one ...
Cava, Jenna - - 2012
We used collection of prey remains, direct observations of hawks with prey, and video cameras at two nests to assess frequency of occurrence and biomass of prey species taken by breeding Cooper's Hawks (Accipiter cooperii) in Victoria, British Columbia, Canada during 1995-2010. Small ([less than or equal to] 27 g) ...
Boesing, Andrea - - 2012
We observed an active nest of the Grey-bellied Hawk (Accipiter poliogaster) in the mixed rainforest of southern Brazil during the 2011 breeding season. The nest was a platform built in the branches of the upper part of a Parana pine (Araucaria angustifolia). The clutch size was two eggs, but only ...
Vilella, Francisco - - 2012
The Red-tailed Hawk (Buteo jamaicensis) is a top predator of upland ecosystems in the Greater Antilles. Little information exists on the ecology of the insular forms of this widely distributed species. We studied movements and resource use of the Red-tailed Hawk from 2000 to 2002 in the montane forests of ...
Saborse, Jacob - - 2012
Twelve Black-capped Chickadees (Poecile atricapillus) were captured and presented with a stuffed Eastern Screech-Owl (Megascops asio) model in areas containing and historically lacking persistent screech-owl populations (n = 4 and 8 chickadees, respectively) to assess whether 'chick-a-dee' calls have a site-specific structure for this dangerous, regionally sympatric predator. These learned ...
Lapergola, Joshua - - 2012
We report the first description of the nest, eggs, and nesting phenology of the Cozumel Vireo (Vireo bairdi), a passerine species endemic to Isla Cozumel, Mexico. We discovered three nests of this species in 2009. These open-cup nests were woven onto branches and hung beneath forks. Clutch size was 2-3 ...
Quilodran, Claudio - - 2012
We installed nest boxes for Thorn-tailed Rayaditos (Aphrastrura spinicauda) and monitored their use in a Monterrey pine (Pinus radiata) plantation in the Maule Region, southcentral Chile. Thirty-four breeding pairs built nests in boxes, of which 75% began laying eggs. Nest establishment began in early September and construction lasted 12.8 [+ ...
Bishop, Jennifer - - 2012
We studied the nesting ecology of Swainson's Warblers (Limnothvlpis swainsonii) in Britton's Neck, South Carolina, USA and found 144 nests of which 78 were active. Nest initiations followed a bimodal distribution. Clutches averaged ([+ or -] SE) 3.19 [+ or -] 0.20 eggs and 2.50 [+ or -] 0.33 fledglings ...
Thompson, Frank R., - - 2012
We examined support for the hypothesis that abundance of Cerulean Warblers (Setophaga cerulea) increases with percentage of bottomland and upland forest, and decreases with percentage of developed land at a local-habitat scale (within a 250-m buffer) and increases with percentage of all forest at a landscape scale (within a 10-km ...
Konter, Andre - - 2012
Population composition of Aechmophorus grebes was investigated in Utah and the occurrence of possible intermediates between Western (Aechmophorus occidenmlis) and Clark's (A. clarkii) grebes was assessed. Individuals with clearly intermediate traits represented an aggregated 6.5% (43 individuals) in the populations investigated while another 7.6% (46 individuals) did not entirely conform ...
Liu, Qiang - - 2012
We equipped five Black-necked Cranes (Grus nigricollis) with satellite transmitters between February and November 2009 to investigate their migration routes between breeding areas and wintering area at Napahai Marsh (3,260 m asl), China. We identified the Shaluli Mountain region (southwest Sichuan), including Daocheng, Litang, Baiyu, and Xinlong counties as a ...
Johnson, James - - 2012
We placed light-level geolocators on 17 Rusty Blackbirds (Euphagus carolinus) in 2009 to track their migrations from nest sites near Anchorage, Alaska to wintering areas and back. We recaptured three of these birds in 2010 and found they departed breeding areas during the first half of September, spent 72-84 days ...
Areta, Juan - - 2012
The winter distribution of neotropical seedeaters (Sporophila spp.) known as capuchinos is poorly known. There are difficulties to understanding their migration patterns: fieldwork is lacking in their wintering areas, their 'eclipse' plumages often make it difficult to identify species, different species share habitats during winter, and there is little or ...
Junda, James - - 2012
We documented unusual variation in the sequence of primary replacement during the prebasic molt of Rufous Fantails (Rhipidura rufifrons) captured in 2009 and 2010 on Saipan, Northern Marianas Islands. Most captures (62%) followed a typical replacement sequence, starting at the proximal primary (P 1) and proceeding distally to the outermost ...
1 2 3 4 5 6 >