1988 Results of Analyzed Mexican Spotted Owl Pellets Collected from the Jemez Mountains. Preliminary Report

DeRosier, Suzanne

This report is a continuation of work started in Methodology and results of analyzed pellets by Mexican spotted owls in the Jemez Mountains (1997), by S. M. DeRosier. The methodology outlined in the 1997 report and slightly revised in the 1999 report is being followed for this analysis and any changes are noted and explained. A total of 728 bags of regurgitated Mexican spotted owl pellets were analyzed to determine the number and prey composition of the digested items. Terry Johnson collected the pellets in 1999 and 2000 from the Jemez Mountains in New Mexico. Each bag contained one pellet sample. A pellet sample consisted of one of the following: A whole pellet, a pellet fragment, loose bones, or any combination of the three. Approximately 5 I 3 pellets were analyzed with pellet size estimated to the nearest 0.25 pellet and loose bones recorded as 0.00 pellet. A pellet equivalent number was estimated to the nearest 0.25 pellet for those samples with loose bones. The pellet number equals the pellet equivalent number for those samples with no loose bones. A pellet equivalent total for these samples was estimated to be 584.75 pellets. A total of 1,897 prey items were identified. The contents of this pellet report include (1) a list of acronyms used in this study [this cumulative list (Appendix A) was updated when new species were found this year, but species found in previous years were not deleted, therefore not all species listed were identified this study year], (2) notes on verifications of prey made at the Museum of Southwestern Biology (Appendix B), (3) the results of the study using a modified spreadsheet of the database (Appendix D & F.), and (4) the database of 1,897 records contained on a CD-RW computer disk with an example shown in Appendix C.