Coarse- and fine-scale patterns of distribution and habitat selection places an Amazonian floodplain curassow in double jeopardy

Abstract

Patterns of habitat selection are influenced by local productivity, resource availability, and predation risk. Species have taken millions of years to hone the macro- and micro-habitats they occupy, but these may now overlap with contemporary human threats within natural species ranges. Wattled Curassow (Crax globulosa), an endemic galliform species of the western Amazon, is threatened by both hunting and habitat loss, and is restricted to white-water floodplain forests of major Amazonian rivers. In this study conducted along the Juruá River, Amazonas, Brazil, we quantified the ranging ecology and fine-scale patterns of habitat selection of the species. We estimated the home range size of C. globulosa using conventional VHF telemetry. To estimate patterns of habitat selection, we used geo-locations of day ranges to examine the extent and intensity of use across the floodplain, which were then compared to a high-resolution flood map of the study area. We captured two females and one male, which we monitored for 13 months between September 2014 and September 2015. Average home range size was 283 ha, based on the 95% aLoCoH estimator. Wattled Curassows selected areas of prolonged flood pulses (six to eight months/year) and had a consistent tendency to be near open water, usually in close proximity to river banks and lakes, especially during the dry season. Amazonian floodplains are densely settled, and the small portions of floodplain habitat used by Wattled Curassows are both the most accessible to hunters and most vulnerable to deforestation. As a result, the geographic and ecological distribution of Wattled Curassows places them at much higher extinction risk at multiple spatial scales, highlighting the need to consider habitat preferences within their conservation strategy.

Diet of the Wattled Curassow (Crax globulosa) on the Juruá River, Brazilian Amazonia

“…To study C. globulosa diet, direct observations were carried out in the field during August 2014 to October 2015. Observations occurred while monitoring three individuals (two females and one male) captured and tagged with VHF transmitters in September and October 2014 (Leite et al 2018), in addition to other individuals observed casually at the study site.…”

“…Although it is present in five South American countries, its ecology is little known, with most knowledge based on anecdotal information Communicated by: Marcos P. Dantas (BirdLife International 2016;. In Brazil, where the largest population is assumed to occur, only four studies of the species have been published (Santos 1998;Haugaasen and Peres 2008;Leite et al 2017;Leite et al 2018).…”

Habitat association in the critically endangered Mangshan pit viper (Protobothrops mangshanensis), a species endemic to China

“…Many wild animals require multiple habitats to obtain various resources (Raynor et al, 2017;Leite et al, 2018), which would provide them opportunities for predation, reproduction, and shelter (Doligez, Danchin & Clobert, 2002;Hyslop, Cooper & Meyers, 2009;O'Hanlon, Herberstein & Holwell, 2015). Effective conservation and management of species depends on an understanding of habitat requirements, particularly if these aspects change seasonally.…”

“…This is especially the case for species susceptible to habitat loss or fragmentation (Willems & Hill, 2009;Ali et al, 2017;Mandlate, Cuamba & Rodrigues, 2019). However, information related to habitat requirements is often scarce when a species has low population densities, narrow and remote habitat, receives little low public attention, and when venomous animals can endanger investigators (Rechetelo et al, 2016;Sutton et al, 2017;Leite et al, 2018). Through investigations into the habitat features associated with a species detection, the important variables that influence habitat association patterns can be found.…”

“…Through investigations into the habitat features associated with a species detection, the important variables that influence habitat association patterns can be found. If the biological resources are limited and patchily distributed across the landscape, the identification and protection of essential habitat components would be critical to population persistence, recovery efforts, and the design of protected areas (Ali et al, 2017;Leite et al, 2018).…”