Together with Dr. Scott Shaffer at San José State University and collaborators at Point Blue Conservation Science, my Master's research focused on the spatial ecology of chick-brooding rhinoceros auklets (Cerorhinca monocerata) nesting within the Farallon Islands National Wildlife Refuge.
Southeast Farallon Island, CA - Through the use of modified GPS data logging devices deployed during the summers of 2015 and 2016, I examined the foraging behavior, marine habitat, and overall distribution of breeding adult auklets in this important southern population. Undertaking both residence time and kernel density analyses, I was able to identify and evaluate areas of intensive use in the surrounding environment. When compared to previous distribution models built using at-sea survey data, I found that breeding auklets appeared to utilize the outer shelf break more frequently than had been otherwise identified. In addition, I noted interannual variability in foraging patterns that appeared to be driven by prey availability and local environmental conditions. Increased late winter upwelling may have contributed to elevated rockfish recruitment and exploitation, with foraging auklets favoring shelf and inner break habitats. Conversely, depressed winter upwelling tends to produce less rockfish, and auklets appeared to respond by targeting alternative prey in the outer break instead. Mixed modeling efforts indicated that a complex three-way interaction between bathymetry, distance to the shelf, and chl a played an important role modulating auklet foraging decisions together with a non-linear sea surface temperature response. I also showed that adults were likely using the same habitats for chick-provisioning as they were for self-provisioning, a behavioral issue with conflicting prior information. Finally, I evaluated the spatial adequacy of three large National Marine Sanctuaries for foraging auklets and found substantial overlapping coverage. This information will hopefully be used by managers and policy-makers when reviewing marine sanctuaries and protected areas, as well as contribute to our scientific knowledge of the species. Published literature describing this research can be found below.
Wilkinson BP, Jahncke J, Warzybok P, Bradley RW, Shaffer SA (2018) Variable utilization of shelf break-associated habitats by chick-brooding rhinoceros auklets in the California Current System. Mar Ecol Prog Ser 590:211-226. https://doi.org/10.3354/meps12500
Wilkinson BP, Jahncke J, Warzybok P, Bradley RW, Shaffer SA (2018) Variable utilization of shelf break-associated habitats by chick-brooding rhinoceros auklets in the California Current System. Mar Ecol Prog Ser 590:211-226. https://doi.org/10.3354/meps12500