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Publications

This list of publications includes peer-review journal articles, official USGS publications series, reports and more authored by scientists in the Ecosystems Mission Area. A database of all USGS publications, with advanced search features, can be accessed at the USGS Publications Warehouse.  

Filter Total Items: 41771

Ecology of mangroves in the Jewfish Chain, Exuma, Bahamas

The structure and function of mangrove communities in the Jewfish Chain, Exumas, Bahamas, were investigated for 3-1/2 years. Mangrove vegetation in the Jewfish Chain is similar to that in all the Caribbean-Florida area; Rhizophora mangle L. dominates and is interspersed with Avicennia germinans (L.) Lamk. and Laguncularia racemosa (L.) Gaertn. There is no apparent zonation of these three species.
Authors
L. V. Wilcox, Thomas G. Yocom, A. M. Forbes

Prevention and control of viral diseases of salmonids

Three viral diseases of salmonids are of worldwide concern: infectious pancreatic necrosis (IPN) viral hemorrhagic septicemia (VHS), and infectious hematopoietic necrosis (IHN). Six principal approaches are being used to prevent or control these diseases: 1) preventing contact o the pathogen with the host, 2) environmental manipulation, 3) immunization, 4) chemotherapy, 5 selective breeding for di
Authors
Donald F. Amend

Physiological response of juvenile coho salmon (Oncorhynchus kisutch) and rainbow trout (Salmo gairdneri) to handling and crowding stress in intensive fish culture

Moving 4–5-in. coho salmon (Oncorhynchus kisutch) held in soft (20 ppm CaCO3) water from the relatively light loading density of 0.5 lb/ft3 to 1, 2, or 4 lb/ft3 (density index, DI = 0.1, 0.2, 0.4, 0.8) caused significant stress as indicated by loss of feeding behavior, but only minimal physiological disturbances, as indicated by lack of hyperglycemia or hypochloremia. However, moving them to 6 or
Authors
Gary A. Wedemeyer

Physiological response to hooking stress in hatchery and wild rainbow trout (Salmo gairdneri)

This study evaluated the physiological response of rainbow trout to hooking stress after being played under standardized conditions (0–5 min) and estimated the time needed for recovery (to 72 h). Plasma osmolality and chloride measurements were used to evaluate osmoregulatory disturbances and gill ion-exchange function, and plasma glucose was used as an index of the generalized nonspecific physiol
Authors
R.S. Wydoski, Gary Wedemeyer, N. C. Nelson

Methylmercury: Second-year feeding effects on mallard reproduction and duckling behavior

For 2 consecutive years mallard (Anas platyrhynchos) hens were fed a control diet or a diet that contained 0.5 or 3 ppm mercury as methylmercury (about 0.1 and 0.6 ppm mercury on the basis of a natural succulent diet). During the fifth egg-collection period, levels of mercury in eggs of hens fed 0.5 and 3 ppm mercury averaged 0.79 and 5.46 ppm, respectively; on a dry-weight basis, the concentratio
Authors
G. H. Heinz

Methylmercury: Second generation reproductive and behavioral effects of mallard ducks

Mallard ducks (Anas platyrhynchos) whose parents were fed a diet containing 0.5 ppm mercury (equal to about 0.1 ppm mercury in a natural diet) also were fed a diet containing 0.5 ppm mercury beginning at 9 days of age and continuing through their reproductive season. Mercury in the eggs of treated hens averaged 0.86 ppm. Hens fed 0.5 ppm mercury made less efficient use of feed and laid a greater p
Authors
G. H. Heinz

Delta-aminolevulinic acid dehydratase: Inhibition in ducks dosed with lead shot

Lead concentration in blood and erythrocyte delta-aminolevulinic acid dehydratase (ALAD) activity was measured in mallard ducks dosed with one all-lead shot or one lead-iron combination shot. For 2 weeks after dosage, lead in blood of ducks given an all-lead shot was fourfold higher than in those dosed with lead-iron shot. At 3 and 4 weeks, the differences in lead residues were directly proportion
Authors
M. T. Finley, M. P. Dieter, L. N. Locke

Sublethal effects of chronic lead ingestion in mallard ducks

Mallard drakes (Anas platyrhynchos) fed 1, 5, or 25 ppm lead nitrate were bled and sacrificed at 3‐wk intervals. No mortality occurred, and the pathologic lesions usually associated with lead poisoning were not found. Changes in hematocrit and hemoglobin concentration did not occur. After 3 wk ducks fed 25 ppm lead exhibited a 40% inhibition of blood δ‐aminolevulinic acid dehydratase activity that
Authors
M. T. Finley, M. P. Dieter, L. N. Locke

Radiometric age map of northern Alaska

This map includes published, thesis, and open-file radiometric data available to us as of June, 1975. Some dates are not plotted because of inadequate location data in the original references.The map is divided into five sections, based on 1:1,000,000 scale enlargements of the National Atlas maps of Alaska. Within each section (e.g., southeastern Alaska), radiometric dates are plotted and keyed to
Authors
Frederic H. Wilson, D. L. Turner