Linked sex harvest strategy for big game management with a test case on black-tailed deer

• Published in: Wildlife monographs 1990 (112), p.3-41
• Main Author: McCullough, D.R
• Format: Article
• Language: English
• Subjects: Age structure; Agricultural seasons; Animal, plant and microbial ecology; Applied ecology; BIG GAME HUNTING; Biological and medical sciences; CALIFORNIA; CALIFORNIE; CAZA; CERVIDAE; CHASSE; Deer; DEER HUNTING; ENVIRONMENTAL ASPECTS; ENVIRONMENTAL IMPACT; Exploitation and management of natural biological resources (hunting, fishing and exploited populations survey, etc.); FAUNE ET FLORE SAUVAGES; Fawns; FORT HUNTER LIGGETT; Fundamental and applied biological sciences. Psychology; GESTION; HUNTING; Hunting seasons; IMPACT SUR L'ENVIRONNEMENT; IMPACTO AMBIENTAL; MANAGEMENT; MULE DEER HUNTING; PLANIFICACION; PLANIFICATION; PLANNING; Population estimates; Population size; Rain; VIDA SILVESTRE; WILDLIFE; Yearlings
• ISSN: 0084-0173; 1938-5455

The Linked Sex Harvest Strategy (LSHS) uses size of the harvests of each sex in relationship to the other to manage for high yield of big game populations. LSHS assumes that the population responds in a density-dependent manner to increased exploitation and that the environment is relatively stable over time. Initially, harvest of 1 sex (typically males) must be heavy compared to harvest of the other. Assuming heavier harvest of males, LSHS involves incremental increases in the female harvest until it constitutes some maximum allowable percentage of the male harvest selected by the manager as a safety margin against overexploitation. If the population responds in a density-dependent manner, incremental female harvest will be followed by lagged increases in male harvest, thereby achieving increased yields of both sexes. Although LSHS is not strictly dependent on anything more than the numbers in the harvest of each sex, analysis of age structure of the harvest by reconstruction methods greatly strengthens the approach. Thus, harvest of each sex can be related to sizes of year-class cohorts and minimum population sizes. We report on a test case of LSHS applied to a population of black-tailed deer (Odocoileus hemionus) on Fort Hunter Liggett (FHL), a 66,776-ha military reservation in California. Analysis of 16 years (1967-82) of harvest data was used to determine harvest in relation to hunting effort, and influence of harvest and environmental variables on population performance. Kill of legal bucks was more a function of the bucks available to be killed than of hunting effort, which was consistently heavy. Kill of does was determined by number of antlerless permits issued. Kill of small bucks (not legal in the forked-antler, bucks-only season) was correlated with kill of does and number of antlerless permits. Variables influencing the size of the buck year-class cohorts recruited were the size of the doe kill in the same year and the amount of rainfall in the previous October, with doe kill accounting for 77% and October rainfall for 23% of identified variance (R2=0.79). Doe kill apparently decreased density and increased fawn recruitment that subsequently yielded a higher buck kill. Burning and domestic livestock grazing were not related to deer productivity. It could not be determined whether or not a downward trend in pellet group population estimates reflected an actual decrease in population size. This analysis was used to make predictions about populat