Observations on Foraging and New Prey Records for the Amazon Treeboa (Corallus hortulanus, Squamata: Boidae)

Abstract

suring 15 km 2 , bordered to the west by the Rio Parnaíba and to the east by Lontras and Mirim creeks. Most of the land is devoted to agriculture, rice in the region that comprises gallery forest and sugarcane and banana plantations in the interior. During May and July 2012, surveys were made for Corallus hortulanus during the lunar phases (new moon, first quarter , full moon, and last quarter) between 1745 h and 0540 h along a creek known by locals as Igarapé dos Camaleões (Fig. 1). The length of the entire creek is 3 km, but only 1.5 km were accessible by canoe. An infrared monocular (Yukon Nightfall) and a video camera with night vision capability (Sony CCD-TRV138) were used to record treeboa behavior. Sixty-four observations on C. hortulanus were made over a period of 288 hours. During moonlit nights between 1800 h and 0034 h, 29 observations were recorded: 23 boas (79.3%) were moving on branches, one was suspended by its tail, one captured an iguana, one captured a bird, and three were coiled with their heads facing down (Fig. 2). During moonless nights between 1800 h and 0145 h, 35 observations were made: 21 boas were moving on branches (60%), 12 were coiled with head facing down (34.3%), one was observed during the shedding process, and one was hanging by its tail, possibly fishing (da Costa Silva and Henderson 2010). The ambient temperature ranged between 28 °C and 25 °C during the hours of 1750-2350 h (the time span during which most snakes were observed). On 18 July 2012, an adult C. hortulanus (approxi-mately1.20 m total length) was observed about 2.3 m from a group of six Great Ani (Chrotophaga major) that were sleeping D espite their relative abundance in many Neotropical lowland snake faunas and the frequency with which they are often encountered, observations on foraging and pre-dation in species of the boid genus Corallus are extremely rare. Henderson (2002) witnessed only one C. grenadensis feeding during 700-800 encounters with the species, and he missed the actual prey capture. More recently, Yorks et al. (2003) and Henderson et al. (2007) have witnessed prey captures by C. grenadensis and C. cookii, respectively. Here we present detailed observations on foraging and prey capture by the geographically and ecologically widespread Amazon Treeboa, Corallus hortulanus (Linnaeus), as well as new records of prey species for C. hortulanus. Observations were made on Batatas Island, Piauí, Brazil. The island represents a small portion of Parnaíba Delta, mea