We tried to capture males around the estimated day of fledging of their nestlings by opportunely timing our capture sessions. |
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For example, blue-footed booby and osprey nestlings fought more when hungry, but great egrets, blue herons and swallow-tailed kites did not. |
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All dead nestlings found within or outside the nest box were subtracted from brood size at day 13 to determine the actual number fledged. |
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Females built the nest and incubated alone, but both parents fed nestlings and fledglings. |
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On our way out of campus, we stopped by Shroud and Bev's apartment to check on the House Finch nestlings. |
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They scavenge for carrion and garbage and also prey on rodents and on the eggs and nestlings of other birds. |
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Birds not ringed as nestlings were aged and sexed according to the method of Jenni and Winkler. |
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In one nest, some nestlings died before 7 days of age and were therefore excluded from the analysis. |
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Birds were ringed as nestlings or when breeding and measured using standard procedures. |
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They are very aggressive and are able to take over nests and kill the eggs and nestlings of other birds. |
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So why do superb fairy-wrens appear to be unique in their ability to desert cuckoo nestlings? |
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It's the first study to show that birds have learned to recognize and reject cuckoo nestlings. |
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At the end of the food deprivation period, we removed all nestlings from their nests and put them in a cloth bag. |
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Both of these nestlings were from the same nest, and the other two nestlings from this nest did match the female at all loci. |
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Magpie nestlings, as well as most nidicolous birds, change skin color from red to orange. |
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Females build the nest, incubate eggs, and brood nestlings, but both sexes choose the nest site and feed offspring. |
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Our largest native flying bird can deliver a nasty nip and the males know no fear when it comes to the defence of their mates and nestlings. |
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To estimate nest age, we candled 1-2 eggs in each nest or aged nestlings from voucher photographs of known-age young. |
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Birds that bring up young cuckoos are unable to distinguish between parasitic nestlings and their own. |
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Two cuckoo and two magpie nestlings were removed from different nests a day before being tested together in a same artificial nest. |
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Unlike common cuckoos, young indigobirds are reared along with their hosts and they mimic the mouth markings of host nestlings. |
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After hatching, the altricial nestlings are brooded for 1 to 2 weeks depending on the weather. |
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As with a lot of birds, chimney swift nestlings make a lot of racket when their parents arrive to feed them. |
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Crows, Cuckoos and Parakeets are very destructive, parakeets not only destroy fruit tree buds but also raid nests and kill nestlings. |
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Because host nestlings remain in the nest, the parasite must compete with host nestlings for food. |
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In passerines, altricial nestlings possess brightly colored gapes and engage in vigorous behavioral displays directed toward a feeding parent. |
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Similarly, parents might lure young from the nest by perching nearby with food or by calling to nestlings. |
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He tied silver cords around the legs of a group of phoebes, and spotted two of the banded nestlings when they returned the next year. |
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In monogamous species, both the male and female build the nest, incubate eggs, brood young and feed nestlings and fledglings. |
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In birds, the nestlings vocalize, stretch their bodies, flap their wings, and jockey for favorable feeding positions in the nest. |
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Males were sampled on average 4 days after they had fledged their nestlings. |
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The eastern garter snake and fox snake will eat nest contents opportunistically, but eggs and nestlings are not major food items in their diets. |
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Various raptor species formed the next most common group, depredating seven nests, all with nestlings. |
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High densities of argasid ticks have been linked to egg and seabird nestlings desertion and lower survival of Cattle Egrets. |
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They have a downward-pointing hook at the end of their upper beak that grows out and disappears by the time the nestlings fledge. |
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In addition, they visit neighboring nests, where they attempt to remove nestlings to induce divorce between the female and the male nest owner. |
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The researchers say that nestlings in at least half of the nests they studied were eaten, mainly by martens and weasels. |
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The number of food deliveries made to supplemented and control nestlings were counted from the observation blind. |
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The hatchlings have a beak with a raptorial hook that they use to stab host nestlings. |
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Other studies even showed that nestlings fed by people were less afraid of new things until age 6 months than were birds reared by their parents. |
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All nestlings were banded, which enabled a study of recruitment to the breeding population. |
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In addition, the amount of food altricial nestlings receive from their parents varies depending on how much food is in the environment. |
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Territorial males sired the majority of offspring, but residents and transients also sired small numbers of nestlings. |
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We wondered what would happen if a female lost her eggs or nestlings to predators and began the nesting cycle anew. |
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Because anis have altricial nestlings, the provisioning help of all breeding adults is essential. |
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We also present data from several 1-year-old birds banded as nestlings and recaptured the following breeding season. |
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Carrion Crow nests are conspicuous and we were able to observe birds delivering food to nestlings using spotting scopes. |
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However, brooding activity was likely finished when nestlings were 10 days old, as chicks are able to thermoregulate at this stage. |
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Single-locus mismatches were interpreted as mutations or mistyping, and such nestlings were conservatively classified as withinpair young. |
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We provided food supplements to half of the nestlings in each nest during the nestling period. |
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Legge showed that the probability of siblicide may be affected both by parental behavior and competitive asymmetries between nestlings. |
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In contrast, effects of brood size on cooling dynamics are much smaller in species whose nestlings sit alongside each other. |
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Parent tree swallows deliver food to nestlings in a bolus, making it difficult to determine either the quantity or quality of food. |
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Unlike certain avian brood parasites, such as cuckoos and honeyguides, hatchling brown-headed cowbirds rarely directly destroy or actively displace host eggs and nestlings. |
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A total of 1072 eggs hatched, and 518 nestlings fledged successfully. |
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Surprisingly, one way that such males can acquire a mate is to kill the young nestlings and then pair with the female who has to start a new family. |
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To monitor the effects of feather-clipping on body condition, females were recaptured and weighed on the second day of incubation and again when nestlings were 4 days old. |
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We returned nestlings to nests as quickly as possibly after processing. |
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How convenient it was that all the prey species were excavating holes and hollows and leafy chambers, and stuffing them with helpless nestlings just when he needed them. |
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All nests that contained eggs or nestlings were classified as occupied. |
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The iguanas also devour sea turtle eggs and shorebird nestlings. |
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Analyses of parental provisioning and nestling growth are confined to 2000 when nestlings ate the supplemental sand lance throughout the nestling period. |
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This is fortunate, because house wren nestlings have prodigious appetites. |
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I noted the number of phoebe and cowbird eggs and nestlings at each visit. |
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All nestlings were returned to their home nests at the end of each trial. |
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We returned nestlings to their nests and repaired cavities with duct tape. |
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If there is no sex-ratio skew among nestlings, data regarding survival of hybrid males and females would be needed to explain the pattern noted by Bronson et al. |
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Neverthless, it is possible that survival rates of nestlings and fledglings might be influenced by spatial factors or by the identity of their social group. |
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Botfly larvae often attack nestlings as do other nest parasites. |
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Cowbird nestlings were placed into nests prior to the hatching of host nestlings to simulate the shorter incubation periods characteristic of parasitic species. |
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At 106 degrees, the eggs will addle or nestlings will die of heat stress. |
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Last year, the towhees built their nest in the clematis vine, and one night a raccoon found it and devoured the nestlings. |
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Supposedly the cowbird chicks would pick parasitic botflies off the rightful nestlings. |
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Remote camera observations revealed that the nestlings died shortly after consuming sand lance, a fish species known to biomagnify saxitoxin. |
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Predators of eggs and nestlings include raccoons, skunks, badgers, foxes, crows and ravens, dogs and owls. |
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In most places, grasshoppers and crickets are the most abundant foods of nestlings. |
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Birds are also reported to be consumed, especially nestlings and even eggs, for which they will climb into shrubbery and bushes. |
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Red-shouldered Hawk nestlings in southern Ohio appeared to be unharmed by infestations of Protocalliphora avium. |
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Peruvian pelicans in Chile have been recorded feeding on nestlings of imperial shags, juvenile Peruvian diving petrels and grey gulls. |
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The diet of Fringillidae nestlings includes a varying amount of small arthropods. |
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On 29 November, nestlings started to open their eyes, the bill was turning blackish and pinfeather started to emerge in the wings, flanks, and back. |
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Adults, nestlings and eggs of other birds are all regularly consumed. |
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Although not typically able to capture a healthy grown bird, eggs, nestlings and fledglings of large bird species can be very attractive to brown bears. |
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When reintroductions have been attempted for peregrines, the most serious impediments were these two owls routinely picking off nestlings, fledglings and adults by night. |
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Spotted Flycatchers have also been observed to feed nestlings prey items deviating from their usual diet, possibly due to travel time pressures during active brood rearing. |
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More rarely, red squirrels may also eat bird eggs or nestlings. |
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So they have learned a bookful of information about the private lives of cliff swallows through the stages of mating, nest building, egg laying, and bringing up nestlings. |
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In contrast, House Wrens are competing cavity nesters and are known to destroy the eggs and nestlings of other cavity nesting birds and take over nest boxes. |
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