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Geology topics

M. J. McCoid

Publications and source records attributed to M. J. McCoid.

7 recordsLinked to original sources

Speculations on colonizing success of the African clawed frog, Xenopus laevis (Pipidae), in California

The African clawed frog has been established in California for over twenty years. During that period, populations have spread to most of the drainage systems in southern California. It is suggested that a suite of contributing factors, including morphological, behavioural, and biochemical predator avoidance strategies, and reproductive and feeding (cannibalism) strategies, have aided in the success of this species in an extralimital situation.

South African Journal of Zoology

Symptoms and circumstances associated with bites by the brown tree snake (Colubridae: Boiga irregularis) on Guam

A review of 94 cases of snakebite by the brown tree snake, Boiga irregularis, in Guam spanning a two year period shows a high proportion (80%) involve victims bitten while sleeping in their homes at night. Some bites apparently involve attempts to feed on small children. Of all children less than 1 yr old that were bitten in a two year period, infants 1-3 mo old comprised 82%. The symptoms exhibited by children are more severe than those experienced by adults. The snake is a rear-fanged (i.e., has enlarged and grooved teeth on the posterior maxillae) colubrid with a moderately large Duvernoy's gland.

Journal of Herpetology

Growth and fatbody cycles in feral populations of the African clawed frog, Xenopus laevis (Pipidae), in California with comments on reproduction

Feral populations of the African clawed frog (Xenopus laevis) exist in several areas of southern California. By following the first cohort of progeny produced by African clawed frogs at a recently colonized site, data on the growth rates and age at first maturity were obtained in field conditions. Females reached maturity at an earlier age than males, grew faster than males, and attained body lengths up to 25% larger than males. Larger females were capable of producing larger numbers of eggs than small females and, therefore, had greater reproductive potential. The relatively stable ambient temperatures of southern California contributed to the possibility of reproduction of clawed frogs during all but the coolest periods of the year. Cycles detected in the mass of fatbodies suggested that nutrients were mobilized from fat prior to and during ovulation. The amount of fat in females varied widely, but fat in males tended to accumulate as the males grew during the study period.

Southwestern Naturalist