LATE SEASON LARVAE, EDEMA, AND ESTIVATION: LESSONS LEARNED FROM CALIFORNIA RED-LEGGED FROGS AT SAN FRANCISCO INTERNATIONAL AIRPORT

Brian Pittman; Environmental Science Associates; bpittman@esassoc.com;

This presentation will review biological observations and lessons learned during habitat enhancement actions at San Francisco International Airport’s West-of-Bayshore property in San Mateo County. Discussion will center upon three uncommon aspects of California red-legged frog (Rana draytonii) biology that were encountered in summer 2022, and how each affected the site enhancement approach. These include aestivating frogs that were discovered during the record-breaking September 2022 heat wave; a localized area where tadpoles and metamorphs expressed severe edema (bloating); and how the finding of overwintering larvae affected site enhancement actions. Field responses to be discussed include the use of a portable vascular doppler meter to detect blood movement in unresponsive aestivating frogs; laboratory treatment methods, pathology reports, and water quality testing results to respond to the observed edema; and efforts to retain floating vegetation (floating marsh pennywort; Hydrocotyle ranunculoides) to maintain habitat and avoid late season California red-legged frog tadpoles.

Reptiles and Amphibians II  InPerson Presentation