White-tailed deer sex identification from faecal DNA and pellet morphometry by neural network and fuzzy logic analyses

Abstract

Knowing the sex of white-tailed deer (Odocoileus virginianus) individuals can provide information to set harvesting rates and management activities. Therefore, the aim of this study is to identify the sex through classification function by using faecal pellet morphometry. Faeces were collected for 12 months in Durango, Mexico; their morphometric variables were measured, the faecal DNA was extracted, and the SRY gene marker was amplified to identify sex. A neural network and fuzzy logic sex classification functions were obtained. The outputs were validated with the SRY gene results. Data from adults in the winter were used to obtain the classification functions. Classification functions could accurately classify sex in 94.4% with neural networks and 86.9% with fuzzy logic. The neural network classified more accurately the sex of adult white-tailed deer studied in winter with the faecal pellets morphometry than with the fuzzy logic analysis. This technique can be a tool for non-invasive studies and monitoring of populations.

Spatial Variation of Population Density and Age Structure of White-Tailed Deer (Odocoileus virginianus) in a Colombian Moor

“…Age Structure and Sex Ratio. When the fecal pellet groups collected throughout the sampling period using the volume ranges proposed by Vega et al (2019), the estimated proportion of age classes (adult, juvenile, and fawn) for the Monterredondo sector was 1:0.29:0, equivalent to 147 adults, 42 juveniles, and no fawns; for La Paila, the proportion was 1:0.57:0.04, corresponding to 69 adults, 39 juveniles and 3 fawns. It is worth noting that La Paila was the only sector where fecal pellet groups corresponding to fawns were found based on their volume.…”

“…Fecal pellet groups were first sorted into three age classes based on pellet volume: fawns (0 mm 3 to 290 mm 3 ), juveniles (291 mm 3 to 605 mm 3 ), and adults (at least 605 mm 3 ; Vega et al 2019). Subsequently, fecal pellet groups in the adult class were sorted by sex using clustering analyses; the first was an analysis of k-means establishing two groups, which corresponded to the two sexes (Mateus-Gutiérrez 2014).…”