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

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Channel catfish response to ultraviolet-B radiation Channel catfish response to ultraviolet-B radiation

Fingerling channel catfish Ictalurus punctatus exposed to simulated ultraviolet-B radiation at an average daily dose of 2.9 J/cm2 were quite sensitive to the radiation. After a 24-h exposure, thinning of the most dorsal epidermis frequently was accompanied by edema. Compared with epidermis of unexposed fish, mucous cells in exposed fish were less superficial and club cells were less...
Authors
M. S. Ewing, V. S. Blazer, D. L. Fabacher, E. E. Little, K. M. Kocan

Sperm-cell ultrastructure of North American sturgeons II: The shortnose sturgeon (Acipenser brevirostrum, Lesueur, 1818) Sperm-cell ultrastructure of North American sturgeons II: The shortnose sturgeon (Acipenser brevirostrum, Lesueur, 1818)

The fine structure of the sperm cell of the shortnose sturgeon (Acipenser brevirostrum) was examined using transmission electron microscopy and selected metrics. The cell possesses a distinct acrosome, a defined head region, a midpiece, and a single flagellum. The mean length of the sperm cell body (acrosome + nucleus + midpiece) is approximately 9.71 µm, and the length of the flagellum...
Authors
M. N. DiLauro, W.S. Kaboord, R.A. Walsch

Changes in haematology during upstream migration to American shad Changes in haematology during upstream migration to American shad

Heart mass of American shad Alosa sapidissima did not change during migration in the Connecticut River. Spleen mass decreased and there was an increase in available blood haemoglobin (+22%) and haematocrit (+9%). The decreases in spleen somatic index (-29%) and spleen haemoglobin content (-15%) were dependent upon distance travelled upriver and not seasonal migration timing or short-term...
Authors
J. B. K. Leonard, S. D. McCormick

Estimating transition probabilities in unmarked populations: Entropy revisited Estimating transition probabilities in unmarked populations: Entropy revisited

The probability of surviving and moving between 'states' is of great interest to biologists. Robust estimation of these transitions using multiple observations of individually identifiable marked individuals has received considerable attention in recent years. However, in some situations, individuals are not identifiable (or have a very low recapture rate), although all individuals in a...
Authors
E.G. Cooch, W.A. Link

Molecular and immunogenetic analysis of major histocompatibility haplotypes in Northern Bobwhite enable direct identification of corresponding haplotypes in an endangered subspecies, the Masked Bobwhite Molecular and immunogenetic analysis of major histocompatibility haplotypes in Northern Bobwhite enable direct identification of corresponding haplotypes in an endangered subspecies, the Masked Bobwhite

The major histocompatibility complex (MHC) is a group of genetic loci coding for haplotypes that have been associated with fitness traits in mammals and birds. Such associations suggest that MHC diversity may be an indicator of overall genetic fitness of endangered or threatened species. The MHC haplotypes of a captive population of 12 families of northern bobwhites (Colinus virginianus)...
Authors
B. M. Drake, R.M. Goto, M.M. Miller, G.F. Gee, W.E. Briles

Questions about Thayer's Gull Questions about Thayer's Gull

In response to recently published articles about the taxonomic status of Thayer's Gull, Larus thayeri, we pose several questions that should be answered before a taxonomic decision can be made.
Authors
R.C. Banks, M.R. Browning

Evaluation of mist-net sampling as an index to productivity in Kirtland's Warblers Evaluation of mist-net sampling as an index to productivity in Kirtland's Warblers

Many applied and theoretical investigations require information on how productivity varies in time and space (Temple and Wiens 1989. DeSante 1995). Examples include studies of habitat quality, population trends, life-history tactics, and metapopulation dynamics. From a demographic perspective, productivity is the number of young counted at a given time of year, produced per adult (e.g...
Authors
J. Bart, C. Kepler, P. Sykes, Carol I. Bocetti

Metal and sediment ingestion by dabbling ducks Metal and sediment ingestion by dabbling ducks

The chemical analysis of intestinal digesta from hunter-killed carcasses or of wildlife scat is a promising means of estimating the exposure of wildlife to those environmental contaminants that, like lead, are poorly absorbed in the digestive tract. When evaluating contaminants at a site, biologists may find the results of this non-destructive approach more straightforward to interpret...
Authors
W. N. Beyer, J. Spann, D. Day

Density and habitat of breeding Swallow-tailed Kites in the lower Suwannee ecosystem, Florida Density and habitat of breeding Swallow-tailed Kites in the lower Suwannee ecosystem, Florida

Historically the Swallow-tailed Kite (Elanoides forficatus) bred in the United States in at least 16 eastern states. Currently it is restricted to seven southeastern states, with most of its breeding range in Florida. Breeding Bird Surveys indicate a declining trend for this Neotropical migrant in most of Florida. Using a rapid survey technique at the Lower Suwannee NWR on 25-27 Mar...
Authors
P.W. Sykes, C. B. Kepler, K.L. Litzenberger, H.R. Sansing, E.T.R. Lewis, Jeff S. Hatfield

Case 3058. Arctocephalus F. Cuvier, 1826 and Callorhinus Gray, 1859 (Mammalia, Pinnipedia): Proposed conservation by the designation of Phoca pusilla Schreber, [1775] as the type species of Arctocephalus; and Otaria Peron, 1816 and Eumetopias Gill, 1866 Case 3058. Arctocephalus F. Cuvier, 1826 and Callorhinus Gray, 1859 (Mammalia, Pinnipedia): Proposed conservation by the designation of Phoca pusilla Schreber, [1775] as the type species of Arctocephalus; and Otaria Peron, 1816 and Eumetopias Gill, 1866

The purpose of this application is to conserve the accustomed understanding and usage of the fur seal name Arctocephalus F. Cuvier, 1826 by the designation of Phoca pusilia Schreber, [1775] as the type species, thus conserving also the name Callorhinus Gray, 1859. At present Phoca ursina Linnaeus, 1758 is the valid type species of both Arctocephalus and Callorhinus. The name...
Authors
A. L. Gardner, C. Brian Robbins
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