COMMISSION

Researchers in the biological sciences have used it
extensively for capturing animals such as mice, voles,
shrews, and squirrels. A survey for an extended period
of trap nights has not occurred since 2010; however,
trapping training nights have been conducted.
Reptiles and Amphibians
Bullfrog Surveys
Sherman trap designed for
the live capture of small mammals
Visual pond surveys for the non-native American bullfrog (Lithobates catesbeianus) were
conducted in the spring of 2015. The purpose of the survey was to determine presence
and location of this species within the park. Bullfrogs were observed in the Coyote Creek
waterway, which includes drainages, sediment basins, and creek segments. They were
observed in the large seasonal pond at the north end of the park, the cottonwood lined
pond near the entrance road, and several other locations.
The bullfrog, while native to the United States, is invasive in
California. In California, the American bullfrog has contributed
to the decline of many native animal populations, including
some species of frogs, turtles, and snakes, by either
outcompeting or preying upon them (California Herps.com
2013). High populations of bullfrogs could lead to the reduction
of species richness and diversity in the park wetlands. Because
of this, bullfrog monitoring and discussions about eradication
measures will continue.
Reptile Pitfall Trapping
With the exception of trapping for staff training purposes, pitfall trapping has not been
done since the pilot year of 2010. In 2010, pitfall traps made of five-gallon buckets were
dug-in and placed by pond, coyote brush, and oak habitats. This trapping helped to build
the reptile inventory of the park, including
the identification of gilbert’s skink (Plestiodon
gilberti), western skink (Eumeces skiltonianus)
and sharp-tailed snake (Contia tenuis).
Amphibian Dip-Netting
Dip-netting for amphibians is conducted
regularly for inventory data. All park ponds were
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California State Parks, Off-Highway Motor Vehicle Recreation Commission