Publications
These publications showcase the significant science conducted in our Science Centers.
Filter Total Items: 16784
Ticks as a factor in nest desertion of California brown pelicans
In summary, our observations suggest that O. denmarki may be an important environmental factor influencing the distribution and success of Brown Pelican nests in the Gulf of California. More information on these relationships may be unobtainable without seriously disturbing and destroying large numbers of nests.
Authors
Kirke A. King, James O. Keith, Christine A. Mitchell, James E. Keirans
Application of census techniques to habitat preservation strategy
Island biogeography concepts applied to breeding bird populations of woodlots clearly explain why certain passerine species typical of tracts of 1 km2 or more are absent from tracts one-half or one-quarter that size. Many 'natural areas' now being preserved are too small to support the complete complement of nesting species; this is partly because little knowledge of the minimum areas required is
Authors
R.F. Whitcomb, C.S. Robbins
Island biogeography and 'Habitat Islands' of eastern forest. III. Long-term turnover and effects of selective logging on the avifauna of forest fragments
No abstract available.
Authors
B.L. Whitcomb, R.F. Whitcomb, D. Bystrak
A comparison of 2 techniques for estimating deer density
We applied mark-resight and area-conversion methods to estimate deer abundance at a 2,862-ha area in and surrounding the Gettysburg National Military Park and Eisenhower National Historic Site during 1987-1991. One observer in each of 11 compartments counted marked and unmarked deer during 65-75 minutes at dusk during 3 counts in each of April and November. Use of radio-collars and vinyl collars p
Authors
C.S. Robbins
Effects of DDE on experimentally poisoned free-tailed bats (Tadarida brasiliensis): Lethal brain concentrations
Adult female free-tailed bats (Tadarida brasiliensis) were collected at Bracken Cave, Texas, and shipped to the Patuxent Wildlife Research Center. Treated mealworms (Tenebrio molitor) containing 107 ppm DDE were fed to 17 bats; five other bats were fed untreated mealworms. After 40 days on dosage, during which one dosed bat was killed accidentally, four dosed bats were frozen and the remaining 17
Authors
D. R. Clark, J.C. Kroll
Experimental feeding of DDE and PCB to female big brown bats (Eptesicus fuscus)
Twenty-two female big brown bats (Eptesicus fuscus) were collected in a house attic in Montgomery County, Maryland. Seventeen were fed mealworms (Tenebrio molitor larvae) that contained 166 ppm DDE; the other five were fed uncontaminated mealworms. After 54 days of feeding, six dosed bats were frozen and the remaining 16 were starved to death. In a second experiment, 21 female big brown bats were
Authors
D. R. Clark, R. M. Prouty
DDE increased the toxicity of parathion to coturnix quail
Adult male Japanese quail (Coturnix coturnix) were exposed to DDE or chlordane in the diet and subsequently dosed with parathion or paraoxon. Pretreatment with 5 or 50 ppm DDE in the diet for 12 weeks resulted in increased cholinesterase (ChE) activity in plasma, but not in the brain. Dietary concentrations of 5 and 50 ppm DDE caused increased susceptibility of quail that were challenged with para
Authors
J. L. Ludke
Status, distribution, and movements of martens in northeastern Minnesota
The decline of martens in Minnesota is reviewed and a recent increase documented. Adjacent and partially overlapping home ranges of 4.3 to 19.9 sq km were determined by telemetry for a female and three males. Habitat use is described. If current trapping and timber management practices persist, martens should continue to increase.
Authors
L. D. Mech, L.L. Rogers
Role of the wolf in a deer decline in the Superior National Forest
White-tailed deer (Odocoileus virginianus) declined in the Superior National Forest of Minnesota between 1968 and 1974. In a 3,000 sq km area of the poorest habitat, deer were decimated. Contributing factors were severe winters, deteriorating habitat, and wolves. Wolves killed older deer, but insufficient fawns were available to replace them.
Authors
L. D. Mech, P.D. Karns
Field List of the Birds of Maryland. Second Edition
No abstract available.
Authors
C.S. Robbins, D. Bystrak