Herpetological Review
IGUANA IGUANA (Green Iguana). COPROPHAGY ZilcA cAmpOS, laboratório de vida selvagem, embrapa Pantanal, CP 109, Corumbá, ms, 79320-900, Brazil (e-mail:
[email protected]); cAROline leuchtenbeRGeR, laboratório de vida selvagem, embrapa Pantanal, CP 109, Corumbá, ms, 79320-900, Brazil (e-mail: caroleucht@gmail. com); ARnAud l. J. deSbieZ, royal Zoological society of scotland, murrayfield, edinburgh, eh12 6Ts, scotland (e-mail:
[email protected]); GuilheRme mOuRÃO, laboratório de vida selvagem, embrapa Pantanal, CP 109, Corumbá, ms, 79320-900, Brazil (e-mail:
[email protected]).
604 Natural History Notes
IGUANA IGUANA (Green Iguana). COPROPHAGY. Iguana iguana occurs from Mexico to Brazil as well as some Caribbean islands (Burghardt and Rand 1982. Iguanas of the World: Their Behavior, Ecology, and Conservation. Noyes Publications, New Jersey. 472 pp.). It is a largely arboreal (Iverson 1982. In Burghardt and Rand, op. cit., pp. 60–76) and herbivorous species, eating mostly leaves, flowers, and fruits from a wide range of shrubs, vines, and trees (Rand et al. 1990. J. Herpetol. 24:211–214). The Green Iguana is reported to occasionally scavenge on animal carcasses (Loftin and Tyson 1965. Copeia 1964:515), as well as eating insects (Hirth 1963. Ecology 44:613–615), or other invertebrates (Fitch 1973. Univ. Kansas Sci. Bull. 50:39–126; Savage 2002. The Amphibians and Reptiles of Costa Rica: A Herpetofauna between Two Continents, between Two Seas. University of Chicago, Chicago, Illinois. 934 pp.). Consumption of bird eggs has also been reported (Schwartz and Henderson 1991. Amphibians and Reptiles of the West Indies: Descriptions, Distributions, and Natural History. Univ. Florida Press, Gainsville, Florida. xvi+720 pp.). In Florida, where the Green Iguana is a well-established exotic species, the examination of stomach contents revealed remains of snails in two individuals, including 12 snails in one juvenile (Townsend et al. 2005. Southeast. Nat. 4:361–354). Coprophagy is generally rare in reptiles, and usually involves eating the feces of other taxa (Frye 1991. Reptiles: An Atlas of Diseases and Treatment. TFH, Neptune City, New Jersey. 637 pp.). The Green Iguana utilizes a microbial fermentation system in its elaborated hindgut to break down plant cell walls (Mackie et al 2004. Physiol. Biochem. Zool. 77:127–138). Hatchlings have been observed to actively associate with adults during the first weeks of life and to consume fresh fecal material from adult iguanas to obtain the complex microflora (Werner et. al 1987. Behav. Ecol.
Sociobiol. 21:83–89). In Galapágos Archipelago, Land and Marine Iguanas (Conolophus pallidus and Ampblyrhynchus cristatus, respectively) have been observed eating feces of crabs and sea lions, and it has been speculated that this is done in order to acquire microorganisms, mostly bacteria, to properly digest various plant chemicals (Mackie et al., op. cit.). In a long term study on the endangered Grand Cayman Blue Iguana (Cyclura lewisi), Goodman (2007. Carib. J. Sci. 43:73–86) reported the consumption of Central American Agouti (Dasyprocta punctata) feces on one occasion. We have found no references in the literature regarding free-living juvenile or adult Green Iguanas feeding on the feces of other animals other than conspecifics. We report here on coprophagy of Green Iguana adults and hatchlings eating feces from Giant Otter (Pteronura brasiliensis) latrines. Giant Otters live in social groups and use latrines to mark their territory (Leuchtenberger and Mourão 2009. Ethology 115:210–216). In December of 2010, during a Giant Otter research trip on the Vermelho River (56.7333°W, 19.6000°S, WGS84; elev. 60 m), in the southern Pantanal, camera traps were positioned at three Giant Otter latrines. These cameras were active in 24-h cycles during three days at latrines 1 and 2, and just one day at latrine 3, resulting in a total of 509 photos of Green Iguanas. All of these photos were during the diurnal period and revealed that both juveniles and adults lizards consumed feces of the otters. The eight photos taken from latrine 1 were consistently of the same adult female, while the five photos from latrine 3 indicated two adult females and one adult male. Detailed examination of the 495 photos taken from latrine 2 indicated that there were at least eight adult females, one adult male, and two juveniles visiting that locale. Often the iguanas visited the latrines soon after the otters left the area. For example, in one case one photo registered eight female iguanas eating feces together, just 15 min. after the otter group had left that latrine (Fig. 1). Giant Otters feed mainly on fish, and their spraints are usually deposited in latrines that are used by the whole group (Duplaix 1980. Rev. Ecol. 34:496–620). Therefore, the spraints containing fish bones and scales probably provide a rich source of calcium for this herbivorous lizard species. Most individuals identified in the photo images were adult females or juveniles which would all have high calcium requirements; adult females due to the production of eggs and juveniles for growth. It may also be speculated that fecal samples provide the reptiles with special microorganisms and bacteria as hypothesized by Mackie et al. (op. cit.).
Fig. 1. Iguana iguana females feeding at a Giant Otter (Pteronura brasiliensis) latrine on the Vermelho River, Southern Pantanal, Brazil.
Herpetological Review 42(4), 2011
Natural History Notes
Another interesting aspect of this behavior is that lizards usually aggregated to the otter latrines. Aggregation of adult female iguanas has been described during the reproductive period where they exhibited a communal nesting strategy, which is often described as an antipredator tactic (Mora 1989. Herpetologica 45:293–298). Group behavior of hatchlings has also been reported as an antipredator strategy (Green et al. 1978. J. Herpetol. 12:169–176). The importance of coprophagy in the dietary supplementation of Iguana iguana is difficult to evaluate. However, this behavior can certainly be precarious for the lizards. While on the ground, the arboreal iguanas are more susceptible to predators and coprophagy facilitates the transmission of parasites from the otters to the iguanas. ZILCA CAMPOS, Laboratório de vida selvagem, Embrapa Pantanal, CP 109, Corumbá, MS, 79320-900, Brazil (e-mail:
[email protected]); CAROLINE LEUCHTENBERGER, Laboratório de vida selvagem, Embrapa Pantanal, CP 109, Corumbá, MS, 79320-900, Brazil (e-mail: caroleucht@gmail. com); ARNAUD L. J. DESBIEZ, Royal Zoological Society of Scotland, Murrayfield, Edinburgh, EH12 6TS, Scotland (e-mail:
[email protected]); GUILHERME MOURÃO, Laboratório de vida selvagem, Embrapa Pantanal, CP 109, Corumbá, MS, 79320-900, Brazil (e-mail:
[email protected]).
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