29th Annual Meeting and Symposium of the
Desert Tortoise Council, February 20-23, 2004
Abstracts

STUDENT PAPER

Quantitative Review of the Adequacy of Knowledge of Different Age Stages of the Desert Tortoise, Gopherus agassizii

Brigette Hagerty, Franziska Sandmeier, C. Richard Tracy

The latest published annotated bibliography on desert tortoises (Gopherus agassizii) identified trends in tortoise research prior to 1991 (Grover and Defalco 1995), and mentioned gaps in knowledge, which influenced research prescriptions in the Desert Tortoise Recovery Plan (1994). The recovery plan highlighted the need for long-term research on desert tortoise demography, threats to persistence, and the effectiveness of mitigation measures (USFWS 1994). The recovery plan prescribed research on non-reproductive age classes. The purpose of our study is two fold: 1) identify gaps in knowledge of immature desert tortoise age classes and 2) compare the foci of research before and after the publication of the recovery plan. We have quantified differences in the knowledge base for different age classes of G. agassizii, and we show gaps in knowledge of the biology of adolescent tortoises where new data are needed to fill the information gaps on the biology of desert tortoises and on the management of tortoise populations.

Grover, M. C. and L.A. DeFalco. 1995. Desert tortoise (Gopherus agassizii): Status-of-knowledge outline with references. U.S. Department of Agriculture, Forest Service, Intermountain Research Station:134 pgs.