Forage diversity and selection in white-tailed deer (Odocoileus virginianus Texanus MEARNS) in coahuila, mexico Forage selection of white-tailed deer in Coahuila
Line interception method, availability, Ivlev, desert scrub, microhistological technique.
Objective: To identify diet diversity and selection among white-tailed deer (Odocoileus virginianus texanus Mearns) at UMA Rancho San Juan, Monclova, Coahuila, Mexico, from October 2018 to August 2019.
Design/methodology/approach: The composition of the white-tailed deer’s diet was identified by applying the microhistological technique. The line interception method was used to estimate the seasonal availability of forage. Diet and forage diversity were established based on the Shannon index, while their relation was identified using a simple linear regression. Diet selection was determined using the chi-squared test and Ivlev’s electivity index.
Results: We identified 49 species and 20 families in the diet, which comprised 49.84% shrubs, 18.38% succulents, 16.02% herbaceous plants, and 15.72% grasses. Deer selected Opuntia engelmannii, consumed Acacia rigidula and Cenchrus ciliaris in proportion to their availability, and consumed Acacia berlandieri, Jatropha dioica, and Karwinskia humboldtiana below their availability.
Study Limitations/Implications: This line of research should be further pursued, including nutritional quality aspects of the forage and diet variations between sampling years. We also recommend fostering the presence of herbaceous plants through habitat improvement techniques.
Conclusions: No relation was found between diet and forage diversity. When forage diversity decreased, grass intake increased.