USGS Science⌕ Search

SEARCH · USGS Science

Results for “Journal of Ornithology”

Search indexed USGS publications on groundwater, aquifers, geologic maps, mineral resources and earthquakes. Explore source records by subject and place.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 271 records · Page 15Linked to original sources

Effectiveness of stewardship and management strategies to conserve coastal bird populations in the northern Gulf of Mexico: A literature review

Shorebirds, seabirds, and wading birds (hereafter coastal birds) have experienced considerable losses over the last century and require proactive conservation management to stabilize or grow populations. Habitat loss and/or degradation and human disturbance are among the most urgent threats faced by coastal bird populations. Identifying effective conservation management techniques to mitigate these threats is of great interest in the northern Gulf of Mexico (nGoM), a region that provides important habitat during the entire life cycle of resident birds and an essential breeding, wintering, and stopover site for migratory birds. A suite of 35 coastal birds have been identified as priority species for multi-scale conservation monitoring in this region by the Gulf of Mexico Avian Monitoring Network (GoMAMN). This review focuses on impacts of human disturbance and anthropogenic habitat loss and/or degradation on coastal birds and effectiveness of the management strategies implemented to mitigate them, with the goal of informing nGoM management. Our review found that human disturbance was best alleviated by simultaneously deploying complementary stewardship techniques (e.g., signs, fencing, steward patrols, education and community involvement, and beach closures to humans, dogs, and vehicles). However, the relative efficacy of each individual technique is unclear given that only 13% of human disturbance management studies and 38% of habitat management studies have been conducted in the nGoM region. Given the nature of coastal bird habitat and associated risks from sea level rise and human development, most habitat management studies encouraged strategic applications of beach renourishment, limitations on beach raking, as well as site- and species-specific restoration strategies. Studies demonstrated that successful management of coastal birds in the nGoM combined these approaches, employing complementary and adaptive strategies over extended periods.

Journal of Field Ornithology↗

Mortality in the Hawaiian Short-eared Owl (Pueo, Asio flammeus sandwichensis): Causes and spatial trends

Trends in wildlife mortality can be particularly challenging to identify in low-density species where mortalities are less likely to be detected or documented. The Pueo, or Hawaiian Short-eared Owl ( Asio flammeus sandwichensis ), is the only native raptor that breeds on all the main Hawaiian Islands. The Pueo is state-listed as endangered on the island of Oʻahu, but drivers of population dynamics are not well known, including causes of mortality. In this study, existing records from organizations across the Hawaiian Islands were compiled to evaluate the causes of mortality in Pueo. Here, 242 unique records spanning the years 1993 to 2024 from state, federal, and private organizations were evaluated for causes of Pueo death. Trauma due to collisions with vehicles, wind turbines, fences, and other human-made objects was the leading detected cause of death (62%) followed by emaciation (13%) and disease (6%), with 19% of deaths due to unknown causes. The islands of Hawaiʻi and Kauaʻi, both with relatively low human populations, had the highest total number of reported mortalities (n = 77, 32%). The highest number of recorded mortalities was in the month of July (16%), and mortalities were generally higher from June through August. Although our study has detection biases, our results are consistent with global studies suggesting that blunt force trauma from vehicles, wind turbines, and other infrastructure are potentially important sources of mortality in raptors. Similar to other studies, rodenticide effects and infectious disease were potentially underestimated as sources of mortality, because most birds did not undergo a full necropsy. Further, there may be confounding variables due to ad hoc data collection. Development of a state-wide system for reporting and recording wildlife mortality along with future studies that include necropsies may improve our ability to discern which sources of mortality may be mitigated.

Hawaii↗

Dive characteristics of Common Loons wintering in the Gulf of Mexico and off the southern U.S. Atlantic coast

Common Loons ( Gavia immer ) winter primarily in marine coastal areas and utilize a forage base that is poorly defined, especially for offshore areas. Information on dive activity is needed for describing foraging strategies and for inferring prey distribution. Archival geolocator tags were used to determine the wintering locations and dive characteristics of adult Common Loons captured and marked on breeding lakes in Minnesota, Wisconsin, and the Upper Peninsula of Michigan. Among loons that completed fall migration, most wintered in the Gulf of Mexico, with smaller proportions wintering off the southern Atlantic Coast or impoundments in the southeastern United States. Adult Common Loons tended to occupy offshore areas of the Gulf of Mexico and the Atlantic Ocean and, on average, spent about 60% of daylight hours foraging. Dive depths were as deep as 50 m (Gulf of Mexico) and dive characteristics indicated that loons were primarily foraging on benthic prey. Total dive duration, time at maximum depth, and post-dive surface intervals increased with dive depths among wintering Common Loons. Our results are expected to contribute to the understanding of the wintering ecology of Common Loons and be useful in informing regional and national conservation planning efforts.

Journal of Field Ornithology↗

Lesser scaup forage on zebra mussels at Cook nuclear plant, Michigan

Nineteen of 21 Lesser Scaup (Aythya affinis) entrained while foraging at the water intake structures of Cook Nuclear Plant, Bridgman, Michigan had consumed zebra mussels (Dreissena polymorpha). The average number of zebra mussels in the upper gastrointestinal tract was 260; maximum number was 987. Migrating Lesser Scaup found this new food source during the first winter following settlement of zebra mussels on the water intake structures of the power plant.

Journal of Field Ornithology↗

Modified transmitter attachment method for adult ducks

The value of radio telemetry for waterfowl research depends on the availability of suitable methods of attaching transmitters. In previous studies, external transmitters attached to adult Mallards (Anas platyrhynchos) with sutures and glue did not stay on birds reliably. In an attempt to improve transmitter retention, a method of attachment was tested in which 4-g transmitters were attached mid-dorsally with sutures and with a stainless steel anchor-shaped wire inserted subcutaneously (anchor transmitters). Field tests indicated that all of 26 female Mallards and 63 of 65 female Gadwalls (Anas strepera) retained their anchor transmitters during 4369 bird-days of monitoring during nesting and brood rearing. Survival rates of females with anchor transmitters compared favorably with those reported from other studies. In this study, females with and without anchor transmitters did not differ with respect to survival rates of their ducklings. The anchor transmitter may be suitable for a variety of field studies on numerous species.

Journal of Field Ornithology↗

Effects of capture and handling on survival of female northern pintails

Identification of capture and handling procedures that influence survival of waterfowl has important research and management implications. We captured 347 female Northern Pintails (Anas acuta) using rocket nets, fitted them with harness (backpack-type) radio transmitters, and monitored their survival during the first 10 d following release. Females were 16 times more likely to die during the first 4 d of exposure than during days 5-10. Survival of females captured with small numbers of waterfowl (n < 172) was not related to holding time (time from capture until release), but survival of females captured with large numbers of waterfowl (n = 594) declined as holding time increased. Survival did not vary with age (immature or adult) or body condition (body mass adjusted for body size) of females. Survival was positively related to flight quality (scored as poor, moderate, or good) of females upon release; poor and moderate fliers were twice as likely to die as those scored in the next higher level of flight quality. Flight quality of females captured with small numbers of waterfowl was unrelated to holding time, but that of females captured with large numbers of waterfowl declined as holding time increased. In all cases where cause of mortalities could be determined (n = 12), we attributed proximate cause of death to predation. We recommend that holding time of ducks be minimized, particularly for those captured with large numbers of waterfowl in rocket nets.

Journal of Field Ornithology↗

Food habits of diving ducks in the Great Lakes after the zebra mussel invasion

Zebra mussels (Dreissena polymorpha) invaded the Great Lakes in the mid-1980s and quickly reached high densities. The objective of this study was to determine current consumption of zebra mussels by waterfowl in the Great Lakes region. Feeding Lesser Scaups (Aythya affinis), Greater Scaups (A. marila), Canvasbacks (A. valisineria), Redheads (A. americana), Buffleheads (Bucephala albeola) and Common Goldeneyes (B. clangula) were collected in western Lake Erie and in Lake St. Clair between fall and spring, 1992-1993 to determine food habits. All 10 Redheads, 97% of Lesser Scaups, 83% of Goldeneyes, 60% of Buffleheads and 9% of Canvasbacks contained one or more zebra mussels in their upper gastrointestinal tracts. The aggregate percent of zebra mussels in the diet of Lesser Scaups was higher in Lake Erie (98.6%) than in Lake St. Clair (54.4%). Zebra mussels (aggregate percent) dominated the diet of Common Goldeneyes (79.2%) but not in Buffleheads (23.5%), Redheads (21%) or Canvasbacks (9%). Lesser Scaups from Lake Erie fed on larger zebra mussels ( = 10.7 i?? 0.66 mm SE) than did Lesser Scaups from Lake St. Clair ( = 4.4 i?? 0.22 mm). Lesser Scaups, Buffleheads and Common Goldeneyes from Lake Erie consumed zebra mussels of similar size.

Journal of Field Ornithology↗

Technique for implanting radio transmitters subcutaneously in day-old ducklings

We developed and evaluated a surgical procedure for implanting radio transmitters in 1-d-old Canvasback (Aythya valisineria) ducklings. Transmitters (1.5 g) were implanted subcutaneously on the back of ducklings while under a general anesthetic, isoflurane, within a few hours of hatching. Evaluations indicate that the procedure is a reliable method for radio-marking ducklings.

Journal of Field Ornithology↗

Determination of hatching date for eggs of black-crowned night-herons, snowy egrets and great egrets

Floatation of eggs in water and specific gravity of eggs of Black-crowned Night-Herons (Nycticorax nycticorax ), Snowy Egrets (Egretta thula ) and Great Egrets (Casmerodius albus ) were evaluated as methods to determine date of hatching. Although specific gravity was a better predictor of hatching date than egg flotation, both techniques were imprecise. The regression between specific gravity and the number of days before hatching differed among clutches, but not among eggs within clutches. Specific gravity of eggs predicted hatching date only to within 3.8 d for Snowy Egrets, and 4.7 d for Black-crowned Night-Herons and Great Egrets. The mean incubation period was 27.3 d for Great Egrets, 23.7 d for Snowy Egrets and 22.8 d for Black-crowned Night- Herons. For all three species, the A egg (first egg laid) had a longer incubation period than the B or C egg.

Journal of Field Ornithology↗

Diet of double-crested cormorants wintering in Texas

The diets of 420 Double-crested Cormorants (Phalacrocorax auritus) were studied during November 1986-March 1987 on eight public reservoirs in Texas. Prey included 29 fish species and the mean live weight of fish per bird was 122 g. Fishes a??415 mm long were ingested, but those a??125 mm accounted for 90% of cormorant food contents by number. Shad (Dorosoma spp.) and sunfishes (Lepomis spp.) accounted for 90% of the total food items by number. Consumption of fishes (percent by weight) was different for male vs. female and adult vs. juvenile cormorants. Total consumption of fish by weight was consistent throughout the period; however, fewer but much larger fish were consumed after 15 February. Cormorants ate fishes that were most abundant in reservoirs. Sport fishes made up a substantial portion of cormorant food by weight, but not by number on some reservoirs. Cormorants ate very few large sport fish, however.

Journal of Field Ornithology↗

Avian cholera in ospreys: first occurrence and possible mode of transmission

In 1994, six Ospreys (Pandion haliaetus) were recovered during the later stages of an epizootic of avian cholera (Pasteurella multocida) in diving ducks and seabirds on Chesapeake Bay in Maryland and Virginia. Pasteurella multocida was isolated from four Ospreys submitted for bacterial examination. This is believed to be the first report of avian cholera in Ospreys. The same isolate, serotype 3,4, was isolated from the Ospreys, diving ducks,and seabirds collected during the epizootic. Possible modes of transmission of avian cholera in Ospreys were either the ingestion of sick waterfowl or use of infected carcasses or bones as nest material.

Maryland, Virginia↗