Publications
These publications showcase the significant science conducted in our Science Centers.
Filter Total Items: 16905
Monitoring tigers and prey: conservation needs and managerial constraints Monitoring tigers and prey: conservation needs and managerial constraints
Contents: -- Introduction -- The sampling-based approach to monitoring -- Defining objectives -- Assessing available resources -- Decision making: Matching objectives and resources -- References
Authors
K. U. Karanth, J.D. Nichols, P.K. Sen, V. Rishi
Ontogenetic behavior and migration of Atlantic sturgeon, Acipenser oxyrinchus oxyrinchus, and shortnose sturgeon, A; brevirostrum, with notes on social behavior Ontogenetic behavior and migration of Atlantic sturgeon, Acipenser oxyrinchus oxyrinchus, and shortnose sturgeon, A; brevirostrum, with notes on social behavior
Ontogenetic behavior of Hudson River Atlantic sturgeon and Connecticut River shortnose sturgeon early life intervals were similar during laboratory observations. After hatching, free embryos were photonegative and sought cover. When embryos developed into larvae, fish left cover, were photopositive, and initiated downstream migration. Free embryos may remain at the spawning site instead...
Authors
B. Kynard, Martin Horgan
Association of methylmercury with dissolved humic acids Association of methylmercury with dissolved humic acids
Sorption of methylmercury (MeHg) to three different humic acids was investigated as a function of pH and humic concentration. The extent of sorption did not show a strong pH dependence within the pH range of 5−9. Below pH 5, a decrease in adsorption for all humic samples was observed. The experimental data for equilibrium sorption of MeHg were modeled using a discrete log K spectrum...
Authors
A. Amirbahman, A.L. Reid, T.A. Haines, J. S. Kahl, C. Arnold
A night seining technique for sampling juvenile Atlantic salmon in streams A night seining technique for sampling juvenile Atlantic salmon in streams
For many studies of the population dynamics, growth, and movement of juvenile Atlantic salmon Salmo salar, it is necessary to resample tagged individuals multiple times. However, common sampling techniques such as electrofishing can have negative effects on fish survival and growth, especially when individuals are repeatedly sampled. We describe an alternative to electrofishing that...
Authors
G. Gries, B. H. Letcher
High-precision measurements of wetland sediment elevation. II The rod surface elevation table High-precision measurements of wetland sediment elevation. II The rod surface elevation table
A new high-precision device for measuring sediment elevation in emergent and shallow water wetland systems is described. The rod surface-elevation table (RSET) is a balanced, lightweight mechanical leveling device that attaches to both shallow ( 1 m) and deep (driven to refusal) rod bench marks. The RSET was built to complement the surface-elevation table (SET), a larger and heavier...
Authors
Donald R. Cahoon, J.C. Lynch, B.C. Perez, B. Segura, R.D. Holland, C. Stelly, G. Stephenson, P. Hensel
Behavioral effects of environmental enrichment on harbor seals (Phoca vitulina concolor) and gray seals (Halichoerus grypus) Behavioral effects of environmental enrichment on harbor seals (Phoca vitulina concolor) and gray seals (Halichoerus grypus)
Zoos and aquariums have been incorporating environmental enrichment into their animal care programs for the past 30 years to increase mental stimulation and promote natural behaviors. However, most attempts to document the effects of enrichment on animal behavior have focused on terrestrial mammals. Staff at the National Aquarium in Baltimore conducted an investigation of the behavioral...
Authors
S. A. Hunter, M. S. Bay, M. L. Martin, Jeffrey S. Hatfield
Role of selenium toxicity and oxidative stress in aquatic birds Role of selenium toxicity and oxidative stress in aquatic birds
Adverse effects of selenium (Se) in wild aquatic birds have been documented as a consequence of pollution of the aquatic environment by subsurface agricultural drainwater and other sources. These effects include mortality, impaired reproduction with teratogenesis, reduced growth, histopathological lesions and alterations in hepatic glutathione metabolism. A review is provided, relating...
Authors
D. J. Hoffman
Producing progeny from endangered birds of prey: Treatment of urine-contaminated semen and a novel intramagnal insemination approach Producing progeny from endangered birds of prey: Treatment of urine-contaminated semen and a novel intramagnal insemination approach
Wild raptors brought into an ex situ environment often have poor semen quality that is further compromised by urine contamination. Generally, it is believed that in birds, artificial insemination into the cloaca or caudal vagina of females requires large doses of high-quality spermatozoa to maximize fertility. In an effort to define and overcome some of the challenges associated with...
Authors
J.M. Blanco, G.F. Gee, D.E. Wildt, A.M. Donoghue
Road log and stop descriptions; Day 1, Stop 1; Delaware Water Gap; geologic overview, stratigraphy, structure, formation of the gap, and glacial geology Road log and stop descriptions; Day 1, Stop 1; Delaware Water Gap; geologic overview, stratigraphy, structure, formation of the gap, and glacial geology
No abstract available.
Authors
Jack B. Epstein
Structural relations along the Taconic unconformity between New York, New Jersey, and Pennsylvania Structural relations along the Taconic unconformity between New York, New Jersey, and Pennsylvania
No abstract available.
Authors
Jack B. Epstein, Peter T. Lyttle
Structural geology of the Delaware Water Gap National Recreation Area Structural geology of the Delaware Water Gap National Recreation Area
No abstract available.
Authors
Jack B. Epstein