Spatial, Dietary and Temporal Niche Dimensions in Ecological Segregation of Two Sympatric, Congeneric Marsupial Species

Abstract

Didelphis aurita and D. albiventris are widely distributed in South America, with a range of sympatry in the limit of their distribution, particularly in Araucaria mixed ombrophilous forest in the southern Atlantic Forest. We investigated the spatial, feeding, and time use between these morphologically similar species in a remnant of Araucaria forest in southern Brazil for one year. We tested the hypothesis that these species when in sympatry segregate each other in space use, diet, and/or activity time. We expect that they segregate between each other primarily in the dimension of space use, as occurs for Australian congeneric marsupials. We used a mark-capture-release protocol for obtaining data. We analysed the spatial segregation by measuring the distance of captures in relation to the remnant centre, stream and edges. There were significant differences in the use of space, as adult females of D. aurita used mainly the remnant interior and stream sides, and D. albiventris females its edges or open areas. The consumption of feeding resources, particularly fruits, was different mainly between females and during the breeding season. However, there was no difference in the activity time between species. We believe that the territorial behaviour of D. aurita females had a crucial role in this spatial segregation with D. albiventris females, leading to a diet differentiation, particularly for fruits which were highly available inside the remnant. Interspecific competition between females is thought to be the main reason maintaining D. albiventris females far from the richest parts of the remnant. The mechanism behind this ecological segregation is discussed, and an ecological niche shift when both species are in sympatry is suggested, rather than the ghost of competition past.

Macaca leonina has a wider niche breadth than sympatric M. mulatta in a fragmented tropical forest in southwest China

“…In the NRW‐NNR, niche differentiation between M. leonina and M. mulatta was revealed in both space and time, and occurred in at least one dimension, as generally suggested by Cáceres and Machado (2013). Schoener (1974) had concluded “Habitat dimensions are important more often than food‐type dimensions, which is important more often than temporal dimension”.…”

“…Defined as the sum of habitat requirements and behaviors of a given species, a niche is multidimensional and includes the distribution, resource‐utilization, dietary requirements, seasonality, and activity rhythm of the species, among other factors (Grinnell, 1917; Hutchinson, 1957). To coexist stably, the niches of sympatric species should differ significantly in at least one dimension (Cáceres & Machado, 2013). Previous studies on primates showed patterns of spatial and temporal fluctuations in various niche dimensions.…”

Nest‐niche differentiation in two sympatric Streptopelia species from a North African agricultural area: the role of human presence

“…Several studies have also highlighted the fact that some species have a greater degree of avoidance to human presence than others (Burger and Gochfield 1991;Smit and Visser 1993;Rodgers and Smith 1995;Gill et al 2001Gill et al , 2007. This is not surprising since closely related species tend to differ ecologically, leading to use of different niche dimensions (Schoener 1974;Caceres and Machado 2013).…”

“…The coexistence of similar species that share resources in the environment is of central interest in community ecology (Begon et al 2006;Atie´nzar et al 2013). Theory stipulates that to coexist, co-occurring species should differ on at least one dimension of their ecological niche (Caceres and Machado 2013). They should use space differently at a small scale.…”

Spatial and seasonal variations in fish assemblages of the Yangtze River estuary

“…food, space/microhabitat, and time) (Schoener, ; Maci and Basset, ). Habitat is the niche axis most frequently partitioned when compared to time and food (Schoener, ; Toft, ; Hofer et al., ), since different use of the space may result in alternative diets for such species, implying possible competitive effects between species (Cáceres and Machado, ). Moreover, whether the observed segregation between the two organisms is caused by competition or by chance can be determined by the null model to compare the expectations (Hofer et al., ).…”