Riparian zone as a main determinant of the structure of lizard assemblages in upland Amazonian forests

Abstract

The use of lizards as model organisms in ecological studies is based on their success in occupying a great diversity of habitats, and some species are closely tied to the environment, which is disadvantaged by the legislation of several countries concerning land use. Our aim was to relate lizard species distribution patterns in rainforest environments to variation in environmental gradients, and provide ecologically based metrics for establishing buffer zones around streams. Lizards were sampled three times in 41 standardised transects near Manaus, Brazil, only in dry season, with Time Limited Visual Search associated with raking through leaf litter. We recorded 20 species from 10 families and used non-metric multidimensional scaling to reduce the dimensionality of quantitative and qualitative compositions of species. Multiple linear regression models indicated that the environmental gradients distance to nearest stream, extent of canopy openness, vegetation density and slope did not significantly influence assemblage species distribution, with an indication of effect of litter depth. By means of piecewise linear regression, the use of riparian zone was estimated at~190 m from quantitative species composition and~211 m from qualitative species composition. Five species occurred only in the riparian zone. Our results suggest that conservation of the entire riparian lizard assemblage in Amazonian rainforest is likely to require protection of at least a 211 m buffer on either side of streams. Abstract in Portuguese is available with online material.

Effect of environmental parameters on squamate reptiles in an urban forest fragment in central Amazonia

“…This effect has been reported in previous studies on herpetofauna (e.g. Vonesh 2001;Whitfield et al 2007;Folt and Reider 2013;) and could be related to an increase of prey and refuge availability both for lizards and snakes (Vitt et al 2008;Fraga et al 2013a;Faria et al 2019). Stream size was not related to either abundance or richness of squamates, as observed for frogs in the same study area (Tsuji-Nishikido and Menin 2011), indicating that lizard and snake assemblages are not strongly related to structural characteristics of these water bodies.…”

“…Stream size was not related to either abundance or richness of squamates, as observed for frogs in the same study area (Tsuji-Nishikido and Menin 2011), indicating that lizard and snake assemblages are not strongly related to structural characteristics of these water bodies. Previous studies in central Amazonia have also shown that squamate assemblages are not affected by stream features, but mainly by the distance gradient in relation to streams (Fraga et al 2011;Faria et al 2019).…”

“…Diversity of forest-dwelling Amazonian squamates can be affected by stream and leaf-litter characteristics that compose the physical structure of the environment occupied by squamates and affect niche dimensions such as thermal conditions and refuge and prey availability (e.g. Pinto 2006;Faria et al 2019;Masseli et al 2019). In Amazonian forest patches, the distance from the edge of the fragment is also known to affect the composition of biological communities such as plants, mammals, birds and amphibians, because a myriad of correlated environmental variables (e.g.…”

Under the light: high prevalence of haemoparasites in lizards (Reptilia: Squamata) from Central Amazonia revealed by microscopy

“…This discrepancy may simply reflect unequal sampling efforts. The methods we used for capture were diversified and effective for certain hosts groups, such as Teiidae and Tropiduridae, but are limited for many lizard species, mainly those that access subterranean microhabitats (Faria et al 2019). Indeed, Teiidae, Tropiduridae and a lizard species, U. superciliosus, were the hosts with highest parasite prevalence.…”

Hierarchical effects of historical and environmental factors on lizard assemblages in the upper Madeira River, Brazilian Amazonia

“…Environmental filtering has been found in Amazonia for plants, frogs, lizards, snakes, and birds [15,[35][36][37][38][39][40][41][42][43]. For lizards, local assemblages may differ due to variation in individual abundance or species turnover along gradients of distance from water courses [31,44], elevation [45], climate seasonality [46], and number of trees [43,47]. Additionally, lizard assemblages may be indirectly structured by species turnover along gradients of canopy openness affecting the availability of thermoregulation sites [48,49], understory-plant density affecting the availability of foraging sites for perching species [50], and clay content in the soil affecting plant composition and food availability [43].…”