What does Rainfall to Groundwater offer for vernal pools?
California tiger salamander (Ambystoma californiense) population segments were federally listed as threatened and endangered early this millennium.
The species is restricted to grasslands and low foothills with pools or ponds that are necessary for breeding.
Natural breeding areas, mostly vernal pools (a seasonal body of standing water), are being destroyed. Ranch stock ponds that are allowed to go dry help take the place of vernal pools for breeding. We are working with ranchers to preserve rangeland. (U.S. Fish & Wildlife Service 2017)
What may we glean from the pattern that many remaining California tiger salamander populations rely on artificial stock ponds to complete their reproductive cycle?
Perhaps that these prehistoric landscapes detained seasonal moisture much later into the dry season than do our existing rangelands?
Tadpoles of Spea hammondii in a vernal pool on Carmel Mountain in San Diego, California, 19 February 2010 by Stickpen (Own work) [Public domain], via Wikimedia CommonsH
Click image to enlarge
Restoring degraded detention storage functions on rangelands for groundwater recharge will simultaneously support restoration of the natural vernal pool habitats California tiger salamander requires, while offering benefits for less demanding amphibians like western spadefoot (Spea hammondii), as well as for floral and general faunal diversity.
Some Groundwater Sustainability Agencies and perhaps other agencies/ organizations may be incentivized to spatially prioritize watershed restoration to enhance existing habitats for California tiger salamander and other vernal pool species while they’re at it.
Vernal pool fairy shrimp swim through the waters of an ephemeral pond Feb. 13 2017 at Travis Air Force Base, Calif. By Heide Couch [Public domain], via Wikimedia Commons
Pogogyne douglasii in the vernal pool at the UC Botanical Garden, Berkeley, California, By Stickpen (Own work) [CC0], via Wikimedia Commons
U.S. Fish & Wildlife Service. 2017. Species Account: California Tiger Salamander Ambystoma californiense. Sacramento Fish & Wildlife Office. https://www.fws.gov/sacramento/es_species/Accounts/Amphibians-Reptiles/es_ca-tiger-salamander.htm
U.S. Fish & Wildlife Service. 2009. Species Account: California Tiger Salamander Ambystoma californiense. Sacramento Fish & Wildlife Office. https://www.fws.gov/sacramento/es_species/Accounts/Amphibians-Reptiles/Documents/california_tiger_salamander.pdf