Global warming is impacting biodiversity by altering the distribution, abundance, and phenology of a wide range of animal and plant species. One of the best documented responses to recent climate change is alterations in the migratory behavior of birds, but the mechanisms underlying these phenotypic adjustments are largely unknown. This knowledge is still crucial to predict whether populations ...

As part of an investigation of an encephalitis outbreak in New York City, we sampled 430 birds, representing 18 species in four orders, during September 13-23, 1999, in Queens and surrounding counties. Overall, 33% were positive for West Nile (WN) virus-neutralizing antibodies, and 0.5% were positive for St. Louis encephalitis virus-neutralizing antibodies. By county, Queens had the most seropo...

In migrating animals protandry is the phenomenon whereby males of a species arrive at the breeding grounds earlier than females. In the present study we investigated the proximate causes of protandry in a migratory songbird, the northern wheatear Oenanthe oenanthe. Previous experiments with caged birds revealed that males and females show differentiated photoperiod-induced migratory habits. How...

The identification and conservation of naturally occurring enemies of crop pests is an important means of improving biological control in cropping systems. One particularly important potential mechanism whereby birds might stabilize and improve pest control is consumption of individual prey that escape mortality from other agents of biological control. We tested the hypothesis that birds prefer...

It is well established that birds use fat stores to primarily fuel migration; however, few studies have focused on the causes and consequences of observed seasonal changes in fatty acid composition of fat stores in birds. We propose and test two hypotheses that address the causes of these seasonal changes in composition of fat stores: (1) diet composition determines fatty acid composition of fa...

One major assumption for endocrine studies is that hormone titers are consistent within an individual so that if hormone titers are low relative to the cohort on one day, they are relatively low compared to the cohort on other days. This is an especially important assumption for most field studies where researchers may have access to an individual animal only once. We used a laboratory study wi...

Newcastle Disease (ND) is an acute, mild to severe, highly infectious and pathogenic disease of domestic poultry, caged and aviary birds as well as wild birds caused by specified viruses of the Avian Paramyxovirus Type 1 (APMV-1) [1,2]. The disease is acute contagious which is characterized by sudden onset and rapid spread within the flock resulting high morbidity and mortality. Newcastle disea...

Gut bacterial communities have been shown to be influenced by diet, host phylogeny and anatomy, but most of these studies have been done in captive animals. Here we compare the bacterial communities in the digestive tract of wild birds. We characterized the gizzard and intestinal microbiota among 8 wild Neotropical bird species, granivorous or frugivorous species of the orders Columbiformes and...

The globally endangered saker falcon ( Falco cherrug ) is currently being re-introduced in Bulgaria, where the falcons are bred captivity and released through hacking method. We relied on birds’ pedigree when forming breeding pairs from 2011. In 2021-2022, we had opportunity to evaluate our captive population via DNA tests. performed first genetic assessment of sakers WRBC a genome evaluation m...

In 1997 and 1998, H9N2 influenza A viruses were isolated from the respiratory organs of Indian ring-necked parakeets (Psittacula Krameri manillensis) that had been imported from Pakistan to Japan. The two isolates were closely related to each other (>99% as determined by nucleotide analysis of eight RNA segments), indicating that H9N2 viruses of the same lineage were maintained in these birds f...