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At least 721 records · Page 40Linked to original sources
USGS1983

Organochlorine residues in Atlantic coast black-crowned night-heron eggs, 1979

Eggs of Black-crowned Night-Herons (Nycticorax nycticorax) were collected in 1979 from two colonies in North Carolina, two colonies in Rhode Island, and one colony in Massachusetts. Mean concentrations of DDE and PCBs were higher in the New England samples than in those from North Carolina, Mean concentrations of organochlorine contaminants in addled eggs collccted at two New England colonies were not significantly different from those in randomly selected eggs. In comparison with the results of a similar study conducted in 1973 at two of the New England colonies, concentrations of DDE in night-heron eggs were lower in 1979, DDD was less frequently detected, DDT and dieldrin were less frequently detected in eggs from one of the two colonies, and eggshell thickness was greater in 1979 for one of the colonies. PCB concentrations in eggs from one colony were lower in 1979 than 1973.

Colonial Waterbirds↗
USGS1983

Organochlorine residues in common tern eggs from nine Atlantic coast colonies, 1980

In 1980, 178 Common Tern (Sterna hirundo) eggs were collected in nine colonies from Rhode Island to North Carolina and were analyzed for organochlorines. DDE and PCBs were detected in most of the eggs. Mean concentrations of DDE and PCBs differed among colonies and seemed related to local contamination. Concentrations of DDE and PCBs in Common Tern eggs were well below those reported to have adverse effects in this species. In one colony, eggs of known laying sequence were collected. First, second, and third eggs in the clutch did not differ significantly from one another in shell weight, shell thickness, and concentration of DDE or PCBs.

Colonial Waterbirds↗
USGS1985

Habitat comparisons and productivity in nesting common terns on the mid-Atlantic coast

Nesting Common Terns (Sterna hirundo) were studied at a number of barrier beaches and small islands of tidal salt marsh in New Jersey and the Eastern Shore of Maryland-Virginina from 1980 through 1982. Data were collected on clutch sizes, nest spacing, and nesting success. The principal null hypothesis tested was that no difference in reproductive success exists between beach and marsh habitats. Nests were monitored from egg-laying in mid-May until mid-July when young fledged. Clutch sizes varied among colonies and across years but no systematic effect of year, habitat, or colony size on mean clutch size per colony was detected. Analyses of nest productivity (estimated using both the Mayfield method and using a colony average) failed to reveal significant effects of habitat or colony size but showed a stronger year effect. Storm tide flooding and egg chick disappearance (presumably predation by Herring Gulls Larus argentatus and Laughing Gulls L. atricilla nesting nearby) accounted for most nest failures. Losses due to both these mortality factors were unpredictable from year to year. Nest spacing in salt marsh colonies was much closer than it was on barrier beaches. In mixed-species colonies with Black Skimmers (Rynchops niger), distances between tern and skimmer nests were also much smaller in marsh colonies than they were on beaches. The limited amount of wrack (windrows of dead, matted vegetation) preferred by marsh-nesting terns probably explains these spacing differences. Several lines of evidence suggest that terns prefer beaches to marshes for nesting, however, the uncertainty of predation and flooding may often obscure any intrinsic differences in habitat quality. Long-term field studies are essential for testing hypotheses related to differential fitness of individuals among habitats.

Colonial Waterbirds↗
USGS1981

Common tern colonies along the mid-Atlantic coast. I. Nestling chronology

1. Sixteen Common Tern colonies in Rhode Island, New Jersey, Virginia, and North Carolina were studied from May through July 1980 by four investigators. Nests were marked during egg laying and were monitored every 5-7 days until fledging of young. 2. Results from 1980 indicate that ambient temperature differences in the four study areas account for differences in the onset of egg laying with North Carolina and Virginia colonies beginning 12-16 days before New Jersey and Rhode Island birds. Temperature alone, however, does not seem to have a significant effect on either median egg-laying dates or total duration of the season. 3. The low frequency of late-season nesting was not correlated with colony size or success of peak nests in 1980, but renesting (or late nesting) in all study areas was rare because of the benign weather conditions during the spring. Similarly, no significant correlation was found between success of nests and colony size.

Colonial Waterbirds↗
USGS1995

Upper Eocene impactites of the U.S. East Coast; depositional origins, biostratigraphic framework, and correlation

Similar successions of planktonic foraminifera, calcareous nannofossils, and bolboformids document coeval deposition of the Exmore impact breccia (Virginia Coastal Plain) and an impact ejecta layer at DSDP Site 612 (New Jersey Continental Slope). Both impactites accumulated in the late Eocene during the early part of biochrons P15 (planktonic foraminifera) and NP 19-20 (calcareous nannofossils), approximately 35.5-35.2 Ma. The impactite at Site 612 is part of an allochthonous debriite, 22.8 cm thick, displaced from the Toms Canyon impact crater, 40 km north-northwest of Site 612. The Exmore breccia, possibly 2000 m thick, is composed of debris displaced from the Chesapeake Bay impact crater, located in southeastern Virginia, 330 km southwest of Site 612.

U.S. East Coast↗
USGS1977

Mid-Atlantic coast osprey population: Present numbers, productivity, pollutant contamination, and status

An estimated 233 + 16 (95% C.I.) pairs of ospreys ( Pandion haliaetus ) nested in coastal New Jersey, Delaware, Maryland, and Virginia in 1975. The present populations were considerably smaller than those reported for selected locations at the turn of the century in these four states. The New Jersey population has continued to decline during the last 25 years, although it showed some signs of improved production in 1974-75. The insecticide DDT was used intensively in New Jersey for mosquito control from about 1946 until 1966; its use in the other states was much less intensive, and of shorter duration. In a segment of the pelaware population of ospreys, production was normal and numbers increased slightly in 1970-75. Fragmentary information from Maryland suggests that the number of pairs nesting on duck blinds was about the same in 1958 and 1975. The population in coastal Virginia north of Cape Henry increased from 1970 to 1975. DDE residues in osprey eggs were highest in the areas showing the greatest population declines and the lowest production rates.

Journal of Wildlife Management↗
USGS1994

Survival rates of American woodcock wintering along the Atlantic coast

Because American woodcock ( Scolopax minor ) populations have been declining, we attached radio transmitters to woodcock at coastal plain sites to determine if survival during winter was involved in the decline. Sites were in Georgia (1982-84, 1989-92), South Carolina (1988-89), and Virginia (1991-92). Survival rates were not different between age or sex classes. Survival rates differed ( P = 0.003) among years. Daily survival rates were lowest ( P = 0.030, S = 0.987) during 1982-83 in Georgia and highest ( P = 0.004, S = 0.999) during 1990-91 in Georgia than in the other years and locations combined ( S = 0.996). We attributed all mortality to raptors and mammals. Compared with other periods of the year, winter was a time of low survival for woodcock. Lower survival rates were possibly a cause of population decline.

Georgia, South Carolina, Virginia↗
USGS2024

Factors affecting the density of Metabetaeus lohena (Decapoda: Alpheidae) at a high-density anchialine pool environment on the Kona Coast of the Island of Hawai‘i

Caridean shrimps (Caridea) are the dominant macroinvertebrates in most anchialine ecosystems. Hawaiian anchialine ecosystems, primarily composed of shallow surface pools connected to the ocean via hypogeal networks of cracks, tubes, and other voids, support 10 caridean shrimp species, including two federally listed as endangered. Little is known about most of these species. The objective of this study was to identify factors that affect the abundance and distribution of Metabetaeus lohena (Alpheidae), an uncommon species found across the Hawaiian Archipelago, at Kaloko-Honokōhau National Historical Park, Island of Hawai‘i. This park supports the highest concentration of anchialine pools in the State of Hawai‘i and is critical to protecting this threatened ecosystem. During 2017, we measured the density of M. lohena during nighttime surveys, as well as a variety of other biological, physical, and chemical parameters, in 130 pools. Metabetaeus lohena occupied 71.5% of the pools surveyed, with a mean density of 7.32 individuals/m 2 (95% CI = 5.14–9.49). Invasive fish and the endemic shrimp Halocaridina rubra (Atyidae) had the strongest effects on M. lohena density, with negative and positive relations, respectively. In the first estimate of M. lohena density at this scale, our data indicate that Kaloko-Honokōhau supports about 11,480 shrimp (95% CI = 8,054–14,906) in the pools surveyed. Furthermore, our models predict that this park could support an additional 1,695 individuals (95% CI = 955–3,008) for a population of about 13,175 shrimp if fish were removed from 19 pools in which M. lohena are absent.

Hawaii↗
USGS1962

Crustal structure along the coast of California from seismic-refraction measurements

Two reversed seismic-refraction profiles were recorded between Los Angeles and San Francisco in 1961. The three shotpoints were located in Santa Monica Bay, offshore near San Francisco, and at Camp Roberts, about halfway between Los Angeles and San Francisco. The velocity of P g along these profiles is 6.1 ± 0.1 km/sec, with possible exceptions near San Francisco and near Los Angeles, where the scatter in the arrival times indicates complex near-surface velocity variations. The velocity of P n between Los Angeles and Camp Roberts is 8.2 ± 0.1 km/sec, and between Camp Roberts and San Francisco 8.0 ± 0.2 km/sec. There is no indication of an intermediate crustal layer in the traveltimes of first arrivals. Computed depths to the Mohorovicic discontinuity, if the crust consists of a single layer, are: 35 km at Los Angeles, 23 km at Camp Roberts, and 23 km at San Francisco. Refractions from crustal layers of intermediate velocity need not appear as first arrivals, and in the extreme, the depth to the Mohorovicic discontinuity may be one-third greater than the thickness of a one-layer crust.

California↗