Use of highway culverts by the water opossum (Chironectes minimus) in southeastern Brazil

Abstract

The water opossum (Chironectes minimus) is a semi-aquatic mammal that is infrequently sampled in Atlantic rainforest areas in Brazil. Here we report on new records of C. minimus in the state of São Paulo, southeastern Brazil, and comment on its behavior and ecology. We placed nine camera traps in culverts and cattle boxes under a highway, between 2017 and 2019. From a total of 6,750 camera-trap-days, we obtained 16 records of C. minimus (0.24 records/100 camera-trap-days) in two cameras placed in culverts over streams. Most of the records were made between May and August, in the dry season and in the first six hours after sunset. The new records are from a highly degraded area with some riparian forests. The records lie approximately 30 km away from the nearest protected area where the species is known to occur. We suggest that C. minimus has some tolerance to degraded habitats, as long as the water bodies and riparian forests are minimally preserved. The new records presented here also fill a distribution gap in western São Paulo state.

Moving far from water: unusual dispersal movement of the water opossum (Chironectes minimus: Didelphimorphia, Didelphidae) in central Brazil

“…Thus, Galliez et al (2009) suggest that degradation of riparian areas may prevent dispersal to adjacent sub-basin. Furthermore, even the very few studies that registered water opossums in degraded habitats indicated that they were still associated with riverine vegetation (Arias-Alzate et al 2021, Prist et al 2020, Brandão et al 2015. Our record indicates, however, that there are exceptions to this strong association.…”

“…However, the water opossum also seems to be able to occur in degraded habitats, with few studies showing that this marsupial is found in degraded riverine forests. Brandão et al (2015) captured an individual in a narrow gallery forest surrounded by monoculture in central Brazil, Prist et al (2020) registered the water opossum in culverts under a highway near a degraded riverine forest in Atlantic Forest biome, and Arias-Alzate et al (2021) described the activity patterns of the water opossum in periurban areas in Colombia. A rapid decline in the potential distribution of the water opossum, however, has been observed, mainly caused by habitat loss and fragmentation (Prieto-Torres & Pinilla-Buitrago 2017).…”

New records of Lophostoma brasiliense Peters, 1867 (Chiroptera, Phyllostomidae) from São Paulo and Mato Grosso do Sul, Brazil

“…With the new record, there are now 81 species of bats confirmed to occur in the state of São Paulo (Garbino 2016;Cláudio et al 2020). The western region of São Paulo is one of the least known areas of the state in terms of mammal diversity, and new findings are still being made in the region (Garbino 2016;Prist et al 2020). The fact that there are only a few protected areas and remaining fragments in western São Paulo should make this region a priority area in future assessments (Rezende 2014).…”

Patrón de actividad de Chironectes minimus (Didelphimorphia: Didelphidae) en ecosistemas periurbanos (Valle de Aburrá-Colombia), con anotaciones sobre su distribución altitudinal

“…La Chucha de Agua o Perrito de Agua (Chironectes minimus) es quizás uno de los marsupiales menos conocidos a lo largo de su distribución en el Neotrópico (Ojeda et al 2002;Galliez et al 2009;De Souza et al 2013). Su rango geográfico se consideró disyunto (Marshall 1978;Stein & Patton 2007), sin embargo, recientemente se ha propuesto como un rango continuo desde el sur de México hasta el norte de Argentina y el este de Brasil (Prist et al 2020). Es una especie que requiere hábitats bien conservados, en lagos y cursos de agua de bosques tropicales (Marshall 1978;Pérez-Hernández et al 2016;Stein & Patton 2007).…”

“…Asimismo, debido a sus requerimientos ecológicos, este patrón de actividad podría verse alterado por efecto antrópico (Muhly et al 2011;Mendes et al 2020). Por lo que sus principales amenazas son la contaminación de las fuentes de agua, la pérdida de hábitat (Palmeirim et al 2014;Pérez-Hernández et al 2016;Solari & Marín-C 2014) y el atropellamiento en las vías (Coelho et al 2008;Delgado-V 2014;Prist et al 2020).…”