Acorns and acorn woodpeckers: ups and downs in a long-term relationship

Abstract

Acorn woodpeckers are one of the most conspicuous and abundant birds in California oak forests due to their unique dependence on acorns, a food resource eaten directly and stored in specialized structures on their territories for later use when acorns are no longer present on trees. Parallel long-term studies of the demography and behavior of this species and of patterns of acorn production by oaks at Hastings Reservation in central coastal California have revealed many ways that acorn crops influence the ecology and behavior of acorn woodpeckers. We present results focusing on the large-scale effects of oaks on the geographical ecology of acorn woodpeckers and how the acorn crop influences woodpecker demography, including the probability that young remain as helpers and the corresponding fitness consequences of this decision.

Parent Publication

• Proceedings of the seventh California oak symposium: managing oak woodlands in a dynamic world

Citation

Koenig, Walter D.; Walters, Eric L.; Knops, Johannes M.H.; Carmen, William J. 2015. Acorns and acorn woodpeckers: ups and downs in a long-term relationship. In: Standiford, Richard B.; Purcell, Kathryn L., tech. cords. Proceedings of the seventh California oak symposium: managing oak woodlands in a dynamic world. Gen. Tech. Rep. PSW-GTR-251. Berkeley, CA: U.S. Department of Agriculture, Forest Service, Pacific Southwest Research Station: 23-34.