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Geology topics

F.B. Turner

Publications and source records attributed to F.B. Turner.

26 records · Page 2Linked to original sources
USGS1970

The demography of the lizard, Uta stansburiana Baird and Girard, in southern Nevada

Between 1966 and 1967 populations of Uta stansburiana in southern Nevada increased about 40%. Over the next year they declined by about 50%. These changes are explained in terms of annual differences in fecundity and survival. Most females laid five clutches of eggs in 1966, but only two or three clutches in 1967. Adult survival between 1966 and 1967 was better than during the following year. The capacity for increase, rc, was estimated as 0.0327/month, and cohort generation time, Tc, as 15.32 months from the 1966-67 data. Data from other natural populations of lizards are reviewed and the inferred net reproductive rates (Ro) compared with the history of the populations. Problems in the study of lizard populations are discussed, particularly the difficulty in assessing egg production by species laying several clutches of eggs each season.

Journal of Animal Ecology↗
USGS1969

A demographic analysis of continuously irradiated and nonirradiated populations of the lizard, Uta stansburiana

A natural population of the lizard Uta stansburiana occupying a fenced 20-acre area in southern Nevada has been exposed to essentially continuous gamma irradiation since February 1964. Tissue doses averaged about 2 rads/day. Nonirradiated populations occupying three adjoining 20-acre areas have also been investigated. Five years of sampling data drawn from the experimental and control populations showed no statistically significant differences in the sex ratios. Comparisons of maximal life span (44 months) and χ 2 tests of age distributions did not indicate a statistically significant difference between the experimental and untreated populations, but the tests were not sensitive to small changes in the proportions of individuals living to the age of 44 months. Both the 59% increase of the irradiated population between 1966 and 1967 and the 43% decline between 1967 and 1968 were generally matched by corresponding changes in the three untreated areas.

Nevada↗