Graduation Date
Fall 2016
Document Type
Dissertation/Thesis
Program
Master of Science degree with a major in Natural Resources, option Wildlife
Committee Chair Name
Dr. Mark Colwell
Committee Chair Affiliation
HSU Faculty or Staff
Second Committee Member Name
Dr. Daniel Barton
Second Committee Member Affiliation
HSU Faculty or Staff
Third Committee Member Name
Dr. Barbara Clucas
Third Committee Member Affiliation
HSU Faculty or Staff
Fourth Committee Member Name
Dr. Micaela Szykman Gunther
Keywords
Common raven (Corvus corax), Humboldt County, Nest exclosure, Predation, Predator management, Western Snowy Plover (Charadrius nivosus nivosus)
Abstract
Common ravens (Corvus corax) are intelligent generalists and a principal predator affecting population recovery of several threatened and endangered species, including the threatened western snowy plover (Charadrius nivosus nivosus). In Humboldt County, raven predation is a primary cause of low nest survival. Nest exclosures, cages around eggs that preclude entry by predators but allow plovers access to incubate, are known to increase nest success. However, speculation exists that exclosures may attract predators. The aims of this study were to summarize corvid distribution on Clam Beach County Park and Little River State Beach, evaluate habitat features associated with corvid activity on the ground, assess how ravens respond to exclosures around artificial plover nests, and to determine if this response changed over time. I used raven tracks as an index to quantify raven activity. Using Generalized Linear Mixed Models (GLMMs), I evaluated overall raven response and response within each of five 28-day trials. There was no evidence that ravens were attracted to exclosures, nor that their responses changed over time. These results suggest that the use of exclosures may be a viable option for managing raven nest predation in Humboldt County in the future.
Citation Style
Journal of Wildlife Management
Recommended Citation
King, Teresa R., "An experimental test of response by Common Ravens to nest exclosures" (2016). Cal Poly Humboldt theses and projects. 10.
https://digitalcommons.humboldt.edu/etd/10