Microhabitat use by species of the genera Bothrops and Crotalus (Viperidae) in semi-extensive captivity

Abstract

Many factors influence microhabitat including climate and the occurrence of predators, prey and suitable shelters. The influence of predators in a semi-extensive breeding system is minimized due to frequent monitoring of the area. This situation enables the independent analysis of such other variables as refuges and temperature. Some specimens of the Viperidae family are kept in a semi-extensive breeding system at the Butantan Institute for display and study. These animals are widely distributed in the Atlantic Forest and Cerrado, two biomes with distinct climatic characteristics. We compared the daily activity pattern and microhabitat use of the species Bothrops jararaca and Crotalus durissus terrificus. Our main questions were whether rattlesnakes and lancehead snakes respond to habitat selection differently in similar climatic conditions and if they choose similar microhabitats. Species of the genus Bothrops were frequently found under shelters regardless of the time of day. On the other hand, snakes of the genus Crotalus were frequently found sheltered during the early morning, then migrated to sunnier areas and returned to shelters in late afternoon.

Snake species richness predicts breeding distribution of short-toed snake eagle in central Italy

“…The result that prey species richness can explain nest-site selection at a very fine scale (1 km 2 ) suggests that optimal breeding sites are placed as close as possible to hunting areas, as has previously been shown for another raptor species, the red kite (Milvus milvus, Pfeiffer & Meyburg 2015). High numbers of prey species could favour the short-toed snake eagle, since different snake species can be active at different times (Ernst et al 2012;Rocha et al 2014) and/or select different microhabitats (Gomes & Almeida-Santos 2012), which increases the probability of the predator contacting potential prey. The stronger relationship at a small scale (1 km 2 ) with respect to larger scales [both the 25 km 2 of the present study and 100 km 2 reported in Moreno-Rueda and Pizarro (2007)] implies that nest-site -Relationship between the presence/absence of short-toed snake eagles and environmental variables at a nest-site (1 km 2 , upper panels) and a landscape scale (25 km 2 , lower panels) in the Latium Region, central Italy.…”

Exposure to fluctuating temperatures leads to reduced immunity and to stress response in rattlesnakes

“…The South American rattlesnake (Crotalus durissus Linnaeus 1758) is a large-bodied member of the Viperidae family, with a wide geographical distribution, found mainly in the Brazilian Cerrado domain (Campbell and Lamar, 1989). Crotalus durissus experiences considerable variation in body temperature (Tozetti and Martins, 2008;Gomes and Almeida-Santos, 2012;Andrade, 2016), which makes this species a good candidate for studying the effect of different thermal regimes on physiological stress and innate immunity.…”

“…The influence of temperature on different physiological parameters is often tested by subjecting animals to constant temperature regimes over a period of many consecutive days (Secor, 2009;Andrade, 2016;Saxon et al, 2018). However, under natural conditions, the body temperature of ectothermic animals (Niehaus et al, 2012;Kingsolver et al, 2015;Colinet et al, 2015), snakes included (Tozetti and Martins, 2008;Gomes and Almeida-Santos, 2012;Andrade, 2016;Brischoux et al, 2016), may exhibit a considerable degree of variation along the circadian cycle. Thus, subjecting ectothermic animals to constant temperature regimes during experiments can be quite different from what they usually experience under natural conditions.…”

Dominant and submissive behaviour in the rattlesnake Crotalus durissus under semi-natural conditions

“…The serpentarium is a semi-natural outdoor enclosure (area = 183.22 m 2 ) designed to keep snakes in a semi-extensive breeding system (Leloup, 1984). It contains a grassy area, circular concrete shelters, artificial concrete burrows, stones, trees, and an artificial river (Gomes & Almeida-Santos, 2012). Snakes were kept under ambient conditions of temperature, photoperiod, and humidity at the time of observations.…”