BS in Biological Sciences
Biological Sciences Department
Global warming influences the biogeography of many marine and terrestrial species. Understanding species range shifts is ecologically and socioeconomically important when guiding management decisions for ecosystems exposed to a rapidly changing climate. In this natural experiment, I follow Danielle Zacherl’s methods (Zacherl et al. 2003) to study the effects of large-scale ocean-atmospheric patterns on recruitment of a marine snail, Kellet’s whelk (Kelletia kelletii); these organisms recently expanded their range North past the geographic barrier of Point Conception to Monterey, CA, USA. I use shell length data collected at 32 subtidal rocky reef kelp forest sites in 2015 (before El Niño) and again in 2016 (after El Niño) to test the effect that El Niño has on recruitment of Kellet’s whelk in its expanded range. After comparing my results to Danielle Zacherl’s findings from the 1997 El Niño event, I found substantial evidence that there is a statistically significant increase in recruitment for Kellet’s whelk in its expanded range after an El Niño event. I also found evidence for differences in population structure between the expanded and historic ranges.