Atributos da história de vida do cachorro-do-mato (Cerdocyon thous): sazonalidade reprodutiva, tamanho de ninhada e investimento parental em uma região antropizada no Brasil Central

Abstract

Life history comprises the set of organismal traits that maximize reproductive success. Attributes such as age and body size at first reproduction, litter size, and parental care are central to evolutionary trade-offs. Understanding the processes shaping these patterns in carnivorous mammals is challenging due to their elusive behavior, large home ranges, and low population densities. This study describes life-history attributes of the crab-eating fox (Cerdocyon thous) in Central Brazil, focusing on reproductive seasonality, litter size, and parental investment. Data were collected between 2010 and 2024 in human-modified landscapes in southeastern Goiás. The breeding season was used as a characteristic of the reproductive cycle to explore a life-history attribute, parturition, which was estimated based on records of pregnancy, lactation, and GPS radio-collar monitoring. Pups were counted when first observed outside dens, with camera traps deployed to assist in monitoring offspring. Body mass data of females and males, as well as female reproductive condition classified as primiparous or multiparous, were related to litter size. Parental investment was assessed through photographic records of adults carrying food and the simultaneous presence of adults and pups. A total of 63 records of female reproductive condition were obtained, including 23 pregnant and 40 lactating females. Pregnant females were observed between June and November, with a peak in July, whereas lactating females predominated between August and November, peaking in September. Estimates of parturition based on 14 independent records indicated events between June and September, with a mean in August, corroborating the expected reproductive seasonality. Nineteen litters were recorded, with a mean of 3,1 pups (sd = 1.6; range: 1–6). We obtained 60 records of adults with pups and 65 records of adults carrying food. Adults carrying food were observed between July and November, and family groups between December and April, indicating that pups remain with their parents for approximately nine months. The observed reproductive seasonality may be associated with greater resource availability during early life stages, which coincide with the end of the dry season and the onset of the rainy season, as well as with prolonged parental care. The description of these reproductive parameters provides robust information on the ecology of the crab-eating fox and is fundamental for understanding the diversity of reproductive strategies within the family Canidae. Additionally, the natural history data presented here contribute to understanding factors influencing population parameters of this species and those with whom it interacts, supporting conservation decision-making, particularly in anthropogenic environments.