The goal of my dissertation was to incorporate habitat quality into metapopulation theory for the conservation of the endangered Ohlone tiger beetle (Cicindela ohlone). Cicindela ohlone is endemic to the few remaining coastal terrace prairies in Santa Cruz County where it forages and lays eggs in bare ground. The prairies were once dominated by bunch grasses, fire, and large grazers that maintained bare ground but now consist of invasive annual grasses with cattle grazing and recreation creating the little remaining bare ground. My dissertation work approached species conservation from multiple scales and each chapter represents those different approaches: habitat quality of metapopulation patches to predict patch conservation value, habitat restoration and adaptive management, population viability analyses, and investigation on how knowledge affects behavior of recreationists in species habitat and the impact of recreation on beetle behavior.
I, along with my collaborators, found that the majority of the remaining Ohlone tiger beetle populations are sustainable and can persist in Santa Cruz County, but only with habitat management. Specifically, creation of bare ground habitat by scraping the ground free of vegetation augments C. ohlone oviposition habitat. Also, requiring cyclists to slow down to speeds of five mph in C. ohlone habitat greatly reduces the negative impact of recreationists on adult behavior. I have shown that these management strategies will increase the growth rates of all C. ohlone populations.
Ensuring that the Ohlone tiger beetle will persist will require not only management of occupied habitats, but also unoccupied sites, particularly to maintain metapopulation dynamics and in the face of the unknown effects of global warming. Habitat management that increases bare ground and forb cover and reduces grass cover, such as controlled grazing, vegetation removal, mowing, or burning are the best options for maintaining C. ohlone persistence. Finally, education and outreach to hikers and bikers in and around Santa Cruz will result in greater understanding and appreciation for C. ohlone conservation and, in turn, result in increased compliance with slowing down in C. ohlone habitats. The Ohlone tiger beetle and its unique coastal prairie habitat can persist into the future, but only with our help.