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T. H. Fritts

Publications and source records attributed to T. H. Fritts.

At least 37 records · Page 2Linked to original sources
USGS1994

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↗
USGS1994

Range and habitats of the desert tortoise

We determined the current range of the desert tortoise (Gopherus agassizii) based on the available latest data from government agencies, the literature, and our experience. We developed the first detailed range map of this species and summarized information about habitat preferences. New records of occurrences were incorporated, and some peripheral localities of questionable authenticity were deleted. The distribution oCG. agassizii covers the broadest range of latitude, climatic regimes, habitats, and biotic regions of any North American tortoise. The northern portion ofits range is in the Mojave Desert of sDuth"eastern California, southern Nevada, southwestern Utah, and northwestern Arizona. The central portion of the range consists of several subdivisions of the Sonaran Desert in southeastern California, western and southern Arizona, and western Sonora, Mexico. The southern edge of its range is in the semitropical Sinaloan thornscrub and Sinaloan deciduous forest of eastern Sonora and northern Sinaloa, Mexico. This species has marked geogi-aphic differences but seems to construct burrows throughout its range.

Fish and Wildlife Research↗
USGS1993

The common wolf snake, Lycodon aulicus capucinus, a recent colonist of Christmas Island in the Indian Ocean

The discovery of the common wolf snake, Lycodon aulicus capucinus , on Christmas I . in the Indian Ocean suggests that individuals of the species have colonised the island recently. On the basis of biological information for this widespread colubrid snake and for the brown tree snake, Boiga irregularis, a well-documented pest species on Guam, the establishment of the common wolf snake would pose a severe threat to the native fauna and ecology of Christmas I. Immediate research is needed to document the spread of the snake, to evaluate its effects on other fauna, and to control or eradicate the species before it becomes firmly established.

Christmas Island↗
USGS1992

The impact of the introduction of the colubrid snake Boiga irregularis on Guam's lizards

The extirpation of Guam's forest avifauna has been attributed to the accidental introduction and subsequent irruption of the brown tree snake, Boiga irregularis . However, recent dietary studies of this nocturnal arboreal snake indicate that it now preys primarily on lizards, not birds. We evaluated the effect the snake has had on Guam's lizards by contrasting lizard communities on Guam with those on adjacent snake-free islands and by comparing the extant lizard communities on Guam with those that were present before the snake arrived. Both comparisons revealed radical reductions in abundance of Guam's native nocturnal lizards and the extirpation of several species. The effect of the snake on diurnal lizards (skinks) is more equivocal. Skinks are still common on Guam, but several species no longer exist on the island. Identification of causes of these extirpations is complicated by the snake's elimination of an important avian skink predator, the concurrent irruption of a shrew, and the effects of predation and competition between the native skinks and an introduced skink.

Journal of Herpetology↗
USGS1989

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↗