MULTI-YEAR MONITORING OF A SYMPATRIC POPULATION OF NEWTS (TARICHA TOROSA AND T. GRANULOSA) IN A COASTAL POND.
Maxwell F. Westphal; US Bureau of Land Management; 1417 Sally Street, Hollister, CA, 95023; (831) 630-9313; mfwestphal11@gmail.com; Emme Nix, Eva Gruber, Michael F. Westphal
Species are expected to undergo significant range shifts as a response to global warming. If range shifts are not uniform in direction and rate among allopatric species, we can expect to see an increase in sympatry among closely-related species, with unpredictable ecological effects and implications for conservation. We tracked the reproduction of two coexisting species of newt that are almost wholly allopatric but can be found in sympatry in a narrow, probably primordial contact zone in coastal Central California. Teasing apart short-term and long-term effects in ecological systems requires multi-year sampling. We conducted uniform sampling of the larval newt guild in 2017 and 2018. We confirmed that T. torosa breeds earlier than T. granulosa, and is largely absent by the end of the summer months whereas relatively young T. granulosa can be present into winter. Large overwintering T. granulosa discovered in early 2017 were not detected in early 2018. We discuss these patterns in a framework of pond-breeding amphibian management that considers late-season drawdowns and reintroduction of Californai red-legged frogs (Rana draytonii), a known prey item of newts.
Poster Session