Influence of the composition and structure of modified landscapes on the abundance of two marsupials during the dry season in Chiapas, Mexico

Abstract

Changes in the landscape due to habitat loss and fragmentation interact with ecological processes of populations, and define the local population abundance. We evaluated the relationship between the abundance of two common marsupials, Didelphis marsupialis (common opossum) and Didelphis virginiana (Virginia opossum), and landscape features in different levels of disturbance at Chiapas, the Highlands and the Central Depression. The goal was to identify effects of changes in the landscape in their populations. Based on the biological characteristics of D. marsupialis and D. virginiana our expectation was to observe higher abundance of opossums in areas with intermediate disturbance. At the same time, establish a relationship between the landscape composition and the abundance of both species. We placed 48 Tomahawk traps in three disturbance levels of the landscape. Within each disturbance level we obtained the structure and composition of the landscape. The abundance of each species was considered as the number of individuals captured. A relative abundance index was estimated from individuals captured by night traps. The influence of the disturbance levels, the landscape, structure, and composition in the abundance of each species was evaluated using multiple regression and generalized lineal model. The average abundance of Didelphis spp. was higher in the Central Depression (5.56 individuals, SD = 4.82). Didelphis marsupialis was captured only in low disturbance with an average of 0.56 individuals (SD = 1.04; Figure 2a), while D. virginiana was captured in the three levels of disturbance with an average of 3.56 individuals (SD = 3.88; Figure 2b). The presence of D. marsupialis was influenced by the number of patches (NP; P = 0.003), while for D. virginiana landscape index was not associated with its presence (Table 2). Our results suggest that the abundance of D. marsupialis and D. virginiana was not influenced by level of disturbance. However, D. marsupialis was related to the number of patches and conserved areas; while D. virginiana was not affected by the landscape attributes evaluated, i. e. composition and configuration, indicating that Virginia opossum can established relatively abundant populations in landscapes highly disturbed. This study contributes to the understanding of the effects of changes in the landscape in common species in Mexico due to human activities.Los cambios en el paisaje debido a la pérdida y fragmentación del hábitat interactúan con procesos ecológicos poblacionales y definen la abundancia poblacional local. Se evaluaron las relaciones entre la abundancia de dos marsupiales comunes, Didelphis marsupialis (tlacuache común) y Didelphis virginiana (tlacuache de Virginia), y los atributos del paisaje en diferentes niveles de disturbio en Chiapas, Los Altos y la Depresión Central. El objetivo fue identificar efectos de cambios del paisaje sobre sus poblaciones. Con base en las características biológicas de D. marsupialis y D. virginiana, nuestra hipótesis fue observar una mayor abundancia ...

Diversity and spatial genetic structure of the common opossum (Didelphis marsupialis) in an urban matrix of Northwestern Colombia

“…It is an opportunistic omnivore, and its diet can easily change depending on the availability of different food types including anthropogenic sources (Ringier 1961). Even though this is species is frequently observed in urbanized areas, its abundance may show seasonal and regional variation (Adler et al 1997;Cruz-Salazar et al 2016), and its distribution may be in uenced by fragmentation and levels of habitat disturbance. The common opossum is not considered a threatened species according to the IUCN (IUCN 2021), but it is a frequent victim of vehicle collisions and acts of aggression in urban areas since it is frequently stigmatized and viewed as a pest (Delgado 2007;Figueroa et al 2009).…”

Potential distribution of marsupials (Didelphimorphia: Didelphidae) in Mexico under 2 climate change scenarios

“…There have been studies analyzing different aspects of marsupials in Mexico, particularly their geographic distribution (Cruz-Salazar et al 2016), the conservation status of didelphid marsupials in PNAs (Medina-Romero et al 2012), habitat suitability (Prieto-Torres and Pinilla-Buitrago 2017), reproduction and development (Cervantes and Oviedo-Martínez 2020), and genetic traits (Cruz-Salazar et al 2014). However, there are no studies on the possible impact of climate change on the distribution of Mexican marsupial species.…”