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Reports on the effectiveness of using late fall hunting seasons to reduce the proportion of female black bears (Ursus americanus) in the harvest are limited, and the geographic scale over which the technique functions as intended has not been examined. During 1992-2000, we radio-equipped black bears in New Mexico, USA, obtained estimates of 175 den entry and 137 den emergence dates, and used New Mexico Department of Game and Fish harvest data (1985-2000) to test for differences in proportion of females in the harvest relative to denning chronology. Bears in northern New Mexico entered dens earlier and emerged later than bears in southern New Mexico (P ≤ 0.001). In northern New Mexico bears displayed the typical pattern of earlier entry and later emergence by reproductive females, proportion of females in the harvest varied over time as expected, and late fall seasons were effective (P ≤ 0.10). In contrast, denning chronology did not differ by sex in southern New Mexico, proportion of females in the harvest did not change over time, and late fall seasons were not effective (P ≥ 0.18). Manipulation of hunting season dates to influence female mortality can be an effective tool, however our study provides an example of an area where denning chronology did not differ by sex and late seasons were not effective. We also observed regional differences in timing of entrance and emergence, which suggest that scale of application may be key. In management jurisdictions that encompass ecologically distinct areas, cover a wide range of latitudes, or are mountainous, successful use of the technique may depend on knowledge of denning chronology at multiple locations and appropriate designation of hunting unit boundaries, season dates, and data analysis units. [ABSTRACT FROM AUTHOR]

Black bear (Ursus americanus) populations are most often managed based on sex and age composition of hunter-killed bears, but few studies have evaluated the method used to determine age. We assessed the accuracy and consistency of aging black bears in New Mexico using the cementum annuli technique by examining age estimates obtained for research-captured and hunter-killed bears. Age estimates were 80% accurate for 30 teeth obtained from 26 known-age bears. Age estimates were consistent with field estimates of age-class for 76% of 232 teeth obtained from captured bears when actual age was not known. Age estimates were consistent between paired teeth for 74% of 232 pairs taken from hunter-killed bears on the same day but for only 46% of 61 pairs taken from study bears during the same or different years. Errors or inconsistencies in age estimation increased with known or estimated age, certainty codes provided by the laboratory, and tooth breakage, but these 3 factors were correlated. Accuracy and consistency also were lower when teeth were removed during the den season. Evidence did not indicate any difference in accuracy and consistency between sexes. In comparisons of 2 blind samples obtained independently, estimated age composition of the harvest did not differ (P=0.92). Accuracy and consistency of the cementum annuli aging technique were relatively high for bears with known or estimated ages < 5 years old; therefore, the method appeared adequate for assessing age composition of annual hunter harvests in New Mexico. [ABSTRACT FROM AUTHOR]