Organochlorine Pesticide Concentrations in Various Species of Migratory Passerines in Louisiana

Twenty-four specimens of southbound migratory passerines comprising 13 species were collected in northeastern Louisiana during 1986, and were subjected to gas-chromatography analyses for organochlorine pesticide compounds. Eleven of the specimens analyzed (46%) were positive for pesticides. The compounds detected were in trace amounts ranging from 1.37 to 200.14 ppb. The data indicated a further decline in pesticide burdens in birds since the ban on DDT. It also supported the hypothesis that a post-mortem breakdown of DDT to DDE may occur in avian tissues. Itis hypothesized that northbound migrants may have higher pesticide burdens than fall migrants considering the continued usage of pesticides in their wintering grounds south of the United States border

Western Kingbird (Tyrannus verticalis): Recently Established Breeding Bird in Arkansas

The Western Kingbird (Tyrannus verticalis) has nested for six consecutive years in Arkansas since 1998. Eleven nests of this species were observed in the summer of 2003 in urban areas of Fort Smith (Sebastian Co.) and Van Buren (Crawford Co.). All nests were on human-made structures. Of the 11, seven (64%) were located on power stations and the remaining four (36%) were on light posts. Mean nest height was 7.92 m (n = 11nests) and the mean width of nest poles was 31.18 cm (n= 4). Nest building lasted 12 to 13 days (mean = 12.5 days, n = 2 nests). The attentive period of female parents (time spent on nest at a stretch during incubation) and their inattentive period were highly variable and averaged 11.97 minutes and 4.08 minutes respectively. The male stayed in close proximity of the nest throughout the nest building and incubation phases. Incubation period was estimated to be 17 days (n = 2 nests). Nesting success (percentage of nests that fledged young) was 72.7% (n = 11 nests). The average number of young fledged per successful nest was 3.37 (n =8) and the average number fledged over all nests was 2.45 (n = 11). In all nests, only the female participated in nest-building and incubation. Fledging occurred 13 to 14 days after hatching (mean =13.5 days, n = 2 nests)

Yellow-rumped Warblers (Setophaga coronata) Sipping Sap from Sapsucker Wells

The Yellow-rumped Warbler (Setophaga coronata) is one of the most ecologically generalized of the warblers. It feeds primarily on invertebrates, but often switches to fruit during winter, utilizing a wide array of foraging maneuvers. It also uses a variety of foraging substrates. Reports of these warblers taking sap from sapsucker wells are rare. Here we report 3 instances of sapsucking Yellow-rumped Warblers from Arkansas. All three observations were immediately preceded by extreme cold weather with snow or ice precipitation. We hypothesize that opportunistic sapsucking from sapsucker holes may be another strategy employed by the species to meet its nutritional requirements during harsh winters, when insects are scarce

Avian Frugivory in a Fruiting Mulberry Tree (Morus rubra) in Arkansas

A fruiting Mulberry tree (Morus rubra) was observed for 67 hours in the spring of 2016 and 2017 in Fort Smith, Arkansas. A total of 172 five-minute scans were performed, during which the following parameters were recorded: species visited, number of individuals of each species, time of visitations, and foraging tier. Between each scan, the foraging rate (number of fruits consumed/min) and inter- and intra- specific aggressive interactions were recorded. A total of 3465 observations of individual birds from 32 species was recorded. Species diversity index was higher in the upper half of the tree. The mean foraging rates for the 6 most commonly observed species ranged from 1.2-2.3 fruits/min. A total of 346 aggressive interactions was observed of which 68% were intraspecific

History and Current Status of the Inca Dove (Columbina inca) in Arkansas

Formerly a bird of Central America, Mexico, and the southwestern United States, the Inca Dove (Columbina inca) has been expanding northward across North America in the past few decades. It first appeared in Arkansas on October 26, 1968 in Saratoga, Howard County. Since then, the statewide range has grown to include at least 36 of 75 counties and is expanding. With the use of Christmas Bird Counts, Breeding Bird Surveys, and two citizen science sources, eBird and AR-Birds, we compiled 368 records of the species in the state. Inca Doves were observed year-round in Arkansas and are expanding its range in the state at an average rate of about one new county every 7 years and 1 new annual encounter about every year. An overview of its overall range in North America indicates that there is enough data to warrant a redrawing of the range map for the species to include most of Arkansas

Remote Ornithology: Studying Nesting Behavior of Bermuda Petrels via Live Webcam

We observed over 167 hours of video of a Bermuda Petrel Pterodroma cahow nest during the 2019 nesting season. The publicly available webcam feed was provided live over the internet by Nonsuch Expeditions and Cornell Lab of Ornithology. Live webcams open new avenues of data collection resulting in observations previously deemed impractical. They help surpass logistic and financial hurdles in conducting field studies. From our offices and homes in Arkansas and New York, we documented behaviors and involuntary movements of the nesting pair in Bermuda. We noted relative roles played by each parent in incubation, and behaviors of the incubating parents such as resting, sleeping, preening, nest maintenance, and moving around. We also measured orientation within the nest. For the first time in seabirds, we provide data on rates of breathing and head shaking

Bird Usage of Black Marasmius Fibers as Nest Material

Black Marasmius fungal fibers have been frequently observed in neotropical bird nests. We tested to determine if superior tensile strength and temperature moderation contributes to why these fibers are preferred by some species over other available nesting materials. Marasmius fibers from nests of Yellow-olive Flycatchers (Tolmomyias sulphurescens) were compared to grass fibers from a Yellow-tailed Oriole (Icterus mesomelas) nest from the same area in Belize, Central America. We measured tensile strengths by a universal strength tester which stretched the fibers to their breaking point. We also used HOBO data loggers to compare the temperature differential between ambient environment and nest interiors in black fiber nests versus the grass fiber nest. Both hypotheses were rejected, suggesting other factors may be operative in the preference of these nest material