When habitat matters: Habitat preferences can modulate co-occurrence patterns of similar sympatric species

Abstract

Disentangling the role of competition in regulating the distribution of sympatric species can be difficult because species can have different habitat preferences or time use that introduce non-random patterns that are not related to interspecific interactions. We adopted a multi-step approach to systematically incorporate habitat preferences while investigating the co-occurrence of two presumed competitors, morphologically similar, and closely related ground-dwelling birds: the brown tinamou (Crypturellus obsoletus) and the tataupa tinamou (C. tataupa). First, we used single-species occupancy models to identify the main landscape characteristics affecting site occupancy, while accounting for detection probability. We then used these factors to control for the effect of habitat while investigating species co-occurrence. In addition, we investigated species present-time partitioning by measuring the degree of overlap in their activity time. Both species were strictly diurnal and their activity time highly overlapped (i.e., the species are not present-time partitioning). The distribution of the two species varied across the landscape, and they seemed to occupy opposite portions of the study area, but co-occurrence models and species interaction factors suggested that the tinamous have independent occupancy and detection. In addition, co-occurrence models that accounted for habitat performed better than models without habitat covariates. The observed co-occurrence pattern is more likely related to habitat preferences, wherein species segregated by elevation. These results provide evidence that habitat characteristics can play a bigger role than interspecific interactions in regulating co-existence of some species. Therefore, exploring habitat preferences while analyzing co-occurrence patterns is essential, in addition to being a feasible approach to achieve more accurate estimation of parameters reflecting species interactions. Occupancy models can be a valuable tool in such modeling.

Assemblage structure and dynamics of terrestrial birds in the southwest Amazon: a camera‐trap case study

“…), Brown Tinamous ( Crypturellus obsoletus ), and Tataupa Tinamous ( Crypturellus tataupa ; Estevo et al. ), all of which show similar diurnal and crepuscular activity as described for the three tinamous in our study.…”

“…, Estevo et al. ) and, among tinamous, daily activity patterns have been described for Little Tinamous (Mosquera‐Muñoz et al. ), Black Tinamous ( Tinamus osgoodi ; Negret et al.…”

“…Estevo et al. () used camera traps to examine overlap of activity between Brown Tinamous and Tataupa Tinamous in southeast Brazil and found no evidence of temporal partitioning. More studies are needed to better understand temporal segregation among sympatric terrestrial birds, particularly in areas where several ecologically similar and congeneric species coexist (e.g., 11 tinamou species in Los Amigos).…”

Secondary forest is utilized by Great Curassows (Crax rubra) and Great Tinamous (Tinamus major) in the absence of hunting

“…Largebodied terrestrial birds have been found to associate with either riparian forest systems or terra firme interior forest (Martínez-Morales 1999, Haugaasen andPeres 2008). Elevation can be important for tinamou distributions (Estevo et al 2017) and has been suggested as a driver of cracid populations (Kattan et al 2016). Camera position on or off trail influences detection probability of rainforest vertebrates (Harmsen et al 2010, Kays et al 2010.…”

Spatial segregation between Chalceus guaporensis and Chalceus epakros (Osteichthyes: Characiformes) in the Madeira River, Amazon Basin

“…Two hypotheses could explain this pattern of co-occurrence: i) slightly different environmental requirements among species (e.g. Estevo et al 2017), with C. guaporensis having greater ability to cope with longitudinal changes in environmental conditions than C. epakros; or ii) competitive interactions between both Chalceus species, resulting in the observed slight overlap (with uneven abundances) at their limits of distribution (Brown and Wilson 1956;Hutchinson 1959;Davies et al 2007).…”