Skip to main content
U.S. flag

An official website of the United States government

Publications

These publications showcase the significant science conducted in our Science Centers.

Filter Total Items: 16743

Circulating growth hormone, cortisol and thyroxine levels after 24 h seawater challenge of yearling coho salmon at different developmental stages Circulating growth hormone, cortisol and thyroxine levels after 24 h seawater challenge of yearling coho salmon at different developmental stages

The response of the endocrine system to short-term exposure to sea water (SW) was examined before, during and after the parr-smolt transformation of coho salmon. Five transfers of yearling coho salmon (Oncorhynchus kisutch) from fresh water (FW) to FW, or from FW to SW for 24 h were carried out between March and September. Condition factor declined significantly in late April, and gill...
Authors
G. Young, Stephen D. McCormick, Bjorn Thrandur Bjornsson, H. A. Bern

Apparent digestibility coefficients of carbohydrates for white sturgeon Apparent digestibility coefficients of carbohydrates for white sturgeon

Apparent digestibility coefficients (ADCs) were determined for white sturgeons (Acipenser transmontanus) fed purified diets containing different carbohydrates. White sturgeons were fed, at a rate of 1.0% body weight!d, diets containing one of nine carbohydrates, and feces were collected by manual stripping following a 2‐week feeding period; chromium sesquioxide (Cr2O3) was used as an...
Authors
M.A. Herold, S. S. O. Hung, K. Fynn-Aikins

Mark-resighting analysis of a California gull population Mark-resighting analysis of a California gull population

California gulls (Larus californicus) of known age and sex were censused on their breeding colony in 1979, 1980 and 1984 through 1993. Ages of 235 males and 196 females ranged from 4 to 27 years. Age classes used in the analysis were limited to 17, 4 through 19, and 20 or more as a final age category because data on gulls over 20 were sparse. Survival declined with age in a way that was
Authors
Bruce H. Pugesek, Chris Nations, K.L. Diem, Roger Pradel

Mycotoxin-induced disease in captive whooping cranes (Grus americana) and sandhill cranes (Grus canadensis) Mycotoxin-induced disease in captive whooping cranes (Grus americana) and sandhill cranes (Grus canadensis)

In 1987, an epizootic in cranes at the Patuxent Wildlife Research Center, Laurel, Maryland, USA, caused illness in 80% of 300 captive whooping cranes (Grus americana) and sandhill cranes (Grus canadensis) and death of 15 of these cranes. Gross pathology findings were inconclusive and consisted of dehydration, atrophy of fat, renal insufficiency, and small spleens. Extensive testing...
Authors
Glenn H. Olsen, J. W. Carpenter, G.F. Gee, N. J. Thomas, F. J. Dein

Successful nesting behavior of Puerto Rican parrots Successful nesting behavior of Puerto Rican parrots

We analyzed nesting behavior of five pairs of the endangered Puerto Rican Parrot (Amazona vittata) during eight successful nesting attempts. Each stage of the nesting cycle (egg laying, incubation, early chick rearing, and late chick rearing) was characterized by distinct trends or levels of behavior. During egg laying, female attentiveness to tile nest increased, and male attentiveness...
Authors
K.A. Wilson, R. Field, M.H. Wilson

Evidence from tooth surface morphology for a posterior maxillary origin of the proteroglyph fang Evidence from tooth surface morphology for a posterior maxillary origin of the proteroglyph fang

Although the front-fanged venom delivery system of the Elapidae is believed to be derived from an aglyphous or opisthoglyphous colubroid ancestor, opinion is divided as to the end of the maxilla on which the proteroglyph fang originated. This study was undertaken to determine whether the evolutionary precursor of the proteroglyph fang was (a) a grooved posterior fang which migrated...
Authors
Thomas H. Fritts, K. Jackson
Was this page helpful?