COMMISSION

In order to monitor aquatic species, surveys are conducted twice in
the spring at known water bodies in the park. This includes 25 stock
ponds and sediment retention basins, as well as sections of Corral
Hollow Creek in both the riding and non-riding areas. Surveys are
typically conducted in April or May and again in May or June. This
timing allows for detection of juvenile amphibians with little to no risk
of egg mass presence (egg masses could be harmed by dip netting).
Monitoring is conducted by a qualified biologist in possession of a
federal 10(a) 1(A) Recovery Permit for California red-legged frog and
California tiger salamandar. The permitted biologist also holds a MOU
Western spadefoot toad
from CDFW to handle listed species as well as a CDFW Scientific Collection Permit. Other
biologists may accompany the permitted biologist and assist with the survey.
During surveys, the water body is approached slowly and quietly and scanned with
binoculars for any sign of amphibians or reptiles. Following the visual encounter survey, the
water body is dip netted. Sampling consists of carefully dipping the net in the water with a
sweeping arc motion, checking the net, and recording any captures by species, including
the total number observed and developmental stage. Typically, the entire perimeter of the
water body is surveyed. A herpetological field guide (Stebbins 1985) and other identification
keys or photographs are used to verify species, if needed. All amphibians are carefully
returned to the water immediately after they are recorded. Turtles are observed by visual
encounter only; no trapping of turtles is conducted. The survey methodology described
allows for a determination of species presence and breeding.
Other data collected during water body surveys includes the weather at the time of the
survey, survey start and stop time, pond capacity, the number of dips made, and number of
observers/biologists conducting the survey.
Due to variation in annual rainfall, including years with very low levels of rain, in some
years water bodies are found to be dry during aquatic species monitoring. Dry water bodies
are recorded as such and no further data is collected. It should be noted that three water
bodies have successively transformed into mule fat thicket and no longer hold water. One
of these is being considered for restoration, and two of these water bodies will be removed
from the map (cannot be restored due to the presence of archaeological resources).
In addition, two ponds have been heavily overgrown with cattails, and would require
vegetation removal to allow for the continuance of open water habitat (de Silva and Meisel
2015, 31-32).
2017 Program Report 89