Abstracts

Abstract: We measured reproductive parameters from 2,833 white-tailed deer (Odocoileus virginianus) does collected from 1978-86 and 1989-93 in 3 geographical regions of Missouri. Fawn pregnancy and fetal rates were significantly lower than those of yearling and older does. Ozark region fawns had lower pregnancy and fetal rates than fawns from the Glaciated Plains region; no other regional differences were found. The only annual diierence for any age class was for fawns between 1992 and 1993. Overall sex ratios were near 1 : 1 and there were no sigdicant relationships between sex ratios and year of collection, litter size, region, or age of doe. Analysis of conception dates indicated that fawn does bred later in the fd than yearling or adult does but there were no regional or annual effects on mean conception dates. Most (75%) of yearling and adult breeding occurred during a 2 week period while 75% of fawn breeding covered 7 weeks. These results indicate that little annual variation in fecundity occurred during the 14- year study for yearling and adult does. Fawn reproductive rates were more variable suggesting that periodic monitoring of fawn reproduction is warranted.