MÉTODO ALTERNATIVO DE AVALIAÇÃO INDICA SAZONALIDADE NO PERÍODO DE ACASALAMENTO DE Philander quica (TEMMICK, 1824)

in the marsupium and lactating females, without considering the phases of the estrous cycle, fertilization and gestation for the duration of the season. Considering that lactation inhibits the estrous cycle of females, studies that relate the reproductive season of marsupials to behavioral or space use patterns without considering whether females are receptive to mating may result in misinterpretations. The objectives of this study were (1) to determine the duration of the period in which female Philander quica (Didelphimorphia, Didelphidae) are receptive to mating; and (2) the duration of the breeding season, also considering the mating period. The capture data came from three sampling grids in a continuous forest area in Garrafão, Serra dos Órgãos National Park, and from 14 Atlantic Forest fragments, in the state of Rio de Janeiro, Brazil. For each female captured with offspring in the pouch, the date of fertilization was estimated by adding the female’s gestation time (15 days) to the age of the offspring, using a non-linear function. The mating period was defined using circular statistics. There were 38 (11 with pups) and 113 (34 with pups) captures of females in the continuous forest and in fragments, respectively. The mating period was seasonal in both areas, occurring from June to December in the continuous forest and from June to November in the fragments. The breeding season was practically continuous throughout the year (June to April), and in the fragments in March and April only lactating females were recorded. Therefore, considering the mating period as information, in addition to the presence of females with offspring or lactating females, can clarify or allow the reinterpretation of behavioral patterns related to the breeding season.