Thomas Custer (Former Employee)

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...

Aquatic birds may serve as indicators of regional metal contamination. Because the food of prefledgling herons (Nycticorax nycticorax ) comes only from areas near the colony, their tissues should reflect local metal contamination. The authors' hypothesis was that prefledgling herons from the Rhode Island colony should have higher concentrations of metals than do those from either the...

Day-old cockerels received 1850 ppm dietary lead for 4 wks. Blood delta-aminolevulinic acid dehydratase (ALAD) activity was reduced to 1.6% of control activity by the end of the study. Hemoglobin concentration (Hb) in lead-exposed cockerels was significantly less than that of controls at 7, 14, and 28 days, and packed cell volume (PCV) was significantly reduced at 14 days. Blood lead...

To estimate reproductive success in a population one ideally would like to determine the number of young fledged per nesting female. However, this is difficult because often (1) the adults are not individually marked, (2) the colony is not visited daily, and (3) the investigator is unable to monitor all young until they fledge. If adults are unmarked and successful renesting occurs...

There have been few consistent reports concerning the frequency and success of nesting attempts by immature night herons of the genus Nycticorax. One- year-old Black-crowned Night Herons (Nycticorax nycticorax) mated to 2-yr-old or older birds built nests and incubated eggs in the wild (Gross 1923). In a captive colony, many 1-yr-old pairs of night herons courted and built nests, and one...

No abstract available.

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...

In 1975 and 1976, eight teams of investigators located 262 colonies of nesting herons and their allies along the Atlantic coast from Florida to Maine. Fourteen species were found in Florida, numbers decreasing to seven in Maine. Colonies censused in the extreme south and north of the study area were lower in number of species and number of adults than those in the intermediate area. More...

No abstract available.

Nests of 5 species of wading birds were identified and marked during the breeding season at 6 locations from Massachusetts to North Carolina. At the end of the breeding season 12 characteristics of nest-site location were measured. Nest locations were mapped to examine dispersion and nearest neighbor relationships. Multivariate analyses were used to describe and compare sites and species...

A dietary dosage of 25 ppm Aroclor 1254 fed to nine-month-old mallards Anas platyrhynchos for at least a month before egg-laying had no detrimental effect on reproductive success or nest attentiveness when hens were allowed to incubate their own eggs. The treatment caused no effect on number of hens laying, date of first egg laid or clutch size. Fertility of eggs was greater among...

No abstract available.