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Publications

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

Filter Total Items: 16783

Age determination of raccoons

Age criteria, based on 61 skulls and eye lenses from 103 known-age captives, are described for separating raccoons (Procyon lotor) into eight age-classes as follows: young-of-the-year, 1, 2, 3, 4, 5, 6-7, > 7 years. Criteria studied were eye lens nitrogen, cranial suture closure, tooth wear and incisor cementum layers. Lens nitrogen increased rapidly up to 12 months of age, but at much reduced r
Authors
G.A. Grau, G.C. Sanderson, J.P. Rogers

Determining parameters for populations by using structural models

A method for calculating parameters necessary to maintain stable populations is described and the management implications of the method are discussed. This method depends upon knowledge of the population mortality rate schedule, the age at which the species reaches maturity, and recruitment rates or age ratios in the population. Four approaches are presented which yield information about the sta
Authors
C. J. Henny, W.S. Overton, H. M. Wight

Whistling swans breeding on the northwest coast of New Quebec

No abstract available.
Authors
J.D. Heyland, E.B. Chamberlain, C.F. Kimball, D.H. Baldwin

1969 Annual banding report

No abstract available.
Authors
L. L. Hood

1969 Inland Canadian banding report

No abstract available.
Authors
L. L. Hood

The 1970 annual meeting of IBBA

No abstract available.
Authors
L. L. Hood

An outbreak of fowl cholera in Everglades National Park

No abstract available.
Authors
R.W. Klukas, L. N. Locke

Challenge infection as a means of determining the rate of disease resistant Trichomonas gallinae-free birds in a population

Trichomonas gallinae-free pigeons and mourning doves were infected with the Jones' Barn strain of T. gallinae to determine the rate of disease resistant T. gallinae-free birds in each population. Although all birds became infected 88% of the pigeons were resistant to trichomoniasis while 82% of the mourning doves were resistant. It was concluded that these birds had been previously infected and sp
Authors
R. M. Kocan, J.O. Knisley

Active anting in the Puerto Rican tanager

Anting, a bird’s intentional exposure of its body surface to chemical substances secreted by ants or other agents, has been recorded in over 20 species of birds of 40 families, mostly within the order Passeriformes. Our observations of anting in the Puerto Rico tanager (Neospingus speculiferus) extend the phenomenon to a new genus and the 14th species of the Thraupidae.
Authors
W.B. King, C.B. Kepler

Passive immunization of pigeons against trichomoniasis

Nonimmune homing pigeons Columba livia were infected with the Jones' Barn strain of Trichomonas gallinae and subsequently transfused with plasma from acute or chronically infected pigeons harboring one of 3 different strains of T. gallinae. The transfusions were either a single 2 mi dose given one day after inoculation or three 1 ml doses given 0, 5, and 10 days after inoculation. Plasma from pi
Authors
R. M. Kocan

Incidence of malaria in a wintering population of canvasbacks (Aythya valisineria) on Chesapeake Bay

Canvasback ducks wintering on Chesapeake Bay had a 6% incidence of Leucocytozoon sirnondi and 2% incidence of Haemoproteus. Sub-inoculation of whole blood into Pekin ducklings produced a Plasmodium infection rate of 31%. Females were more frequently infected (12/22) than males (15/68). The parasite was identified as P. circumflexum.
Authors
R. M. Kocan, J.O. Knisley

Woodcock feeding habits as related to summer field usage in central Maine

In 1968 and 1969, 60 American woodcock (Philohela minor) were collected before and after alighting on summer fields in central Maine. A comparison of stomach contents from these birds showed that woodcock fed prior to entering fields at dusk. No evidence was found to indicate that any substantial amount of food was eaten by birds remaining on fields throughout the night. In 1968, the availabili
Authors
W.B. Krohn