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Publications

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

Filter Total Items: 16782

Teratogenic effects of external egg applications of methyl mercury in the mallard, Anas platyrhynchos

The embryotoxic potential of external applications of methyl mercury on mallard eggs was investigated to assess the possible impact of mercury transferred from the plumage of effluent-contaminated aquatic birds to their eggs. Eggs were treated on day 3 of development with microliter applications of methyl mercury that was dissolved with ethyl acetate into an aliphatic hydrocarbon vehicle. Mercury
Authors
D. J. Hoffman, Johnnie N. Moore

Comparison of game-farm and wild-strain mallard ducks in accumulation of methylmercury

The accumulation of mercury was compared in game-farm and wild-strain mallard ducks fed a diet containing 0.5 ppm mercury in the form of methylmercury dicyandiamide. There were no significant differences between the two strains in levels of mercury that accumulated in blood, kidney, liver, breast muscle, brain, eggs, or ducklings. Mercury levels in blood were significantly correlated with levels i
Authors
G. H. Heinz

Effects of aldrin exposure on snow geese in Texas rice fields

In 1972 and 1974, 112 dead or moribund snow geese (Chen c. caerulescens), mostiy immature white-phase males, were found in a 'study area on the Garwood Prairie, Texas. Dying geese were observed within 2 days after rice fields planted with aldrin-treated seed were flooded by heavy tains6n 21 March 1972 and 25 March 1974. Brains from 8 snow geese that were moribund when found contained an average
Authors
Edward L. Flickinger

Annual weight cycle in wild screech owls

The annual weight cycle of wild birds of prey has received little attention in the past, primarily because of the difficulty in capturing and recapturing them. Screech Owls (Otus asio) are resident in our northern Ohio study area and readily occupy nest boxes established for Wood Ducks (Aix sponsa) (see VanCamp and Henny 1975). In addition to nesting in the boxes, the owls use them as roosting and
Authors
Charles J. Henny, Laurel F. VanCamp

Elimination of endrin by mallard ducks

Endrin is very toxic to birds and has been implicated in the deaths of birds in nature. However, it is not known how rapidly birds eliminate endrin, a factor important in determining how much is accumulated in tissues. In this study, the loss rate of endrin was followed for 64 days in mallard (Anas platyrhynchos) drakes that had been fed 20 ppm endrin for 13 days. The loss from carcass and blood w
Authors
G. H. Heinz, R. W. Johnson

Cholinesterase activity in Japanese quail dusted with carbaryl

Japanese quail (Coturnix coturnix japonica) were dusted with 5% carbaryl to determine if this topical treatment would alter plasma and brain cholinesterase activities. Within 6 hours after dusting, plasma cholinesterase activity was depressed compared with controls, the depression averaging 20% for females and 27% for males. By 24 hours the cholinesterase activity of females had returned to normal
Authors
E. F. Hill

An improved method of censusing deer in deciduous-coniferous forests

No abstract available.
Authors
T.J. Floyd, L. D. Mech, M.E. Nelson

Return of the swift fox to northern Great Plains

No abstract available.
Authors
C. N. Hillman, J.C. Sharps

Wolf howling and its role in territory maintenance

An experimental study of the role of howling in wolf territory maintenance was conducted in the Superior National Forest, Minnesota. Vocal replies and behaviour of radio-collared wolves in response to human howls were analyzed for eight packs and 10 lone wolves during a 2-year period. Reply rate varied significantly throughout the year. A mid-winter increase was correlated with the breeding season
Authors
F.H. Harrington, L. D. Mech

Hawk count research

No abstract available.
Authors
M.R. Fuller