Evidence of Spatiotemporal Planning in a Panther Chameleon (Furcifer Pardalis) on the Masoala Peninsula, Madagascar
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Herpetology Notes, volume 12: 909-911 (2019) (published online on 29 August 2019) Evidence of spatiotemporal planning in a panther chameleon (Furcifer pardalis) on the Masoala Peninsula, Madagascar Timothy M. Eppley1,2,* The panther chameleon Furcifer pardalis (Cuvier, Andreone et al., 2005). Though frequently observed, 1829) is widely distributed throughout the central- there are few written accounts of egg deposition by northeastern and northwestern regions of Madagascar, panther chameleons in the wild (Rabearivony et al., where it occupies a wide range of humid, semi-humid, 2007). Here, I report an unusual behaviour of nesting and transitional habitats (Ferguson et al., 2004; Glaw and and egg deposition in a panther chameleon. Vences, 2007). Unlike most other Malagasy chameleons, The following observation was made at the Andranobe panther chameleons appear to be edge specialists and are field site (15.6816°S, 49.9573°E) located along the more often found in anthropogenic habitats compared to west coast of Masoala National Park in northeastern intact continuous canopy forests (Andreone et al., 2005; Madagascar. On 28 February 2019, I observed a Rabearivony et al., 2007). Panther chameleons are female panther chameleon move on the ground across actively collected and sold for the international pet trade approximately 4 m of open-canopy grass to an area (Andreone et al., 2005; Carpenter et al., 2005), yet there of exposed sandy soil bordering a field station used is a current lack of information on their natural history previously by Madagascar National Parks officials and and reproduction in the wild. researchers. At 1140 h, the pinkish/orange-coloured In general, this species is diurnal and almost exclusively female began excavating a hole in the sandy substrate. solitary, and it is speculated that females maintain fixed As this digging commenced, she turned a deep blue home ranges (Gehring et al., 2008). Males are larger and coloration. Originally her digging was directed towards heavier than females, displaying significant sexual size the south (i.e., the burrow opened to the north), but with dimorphism in addition to sexual dichromatism, with the widening hole at approximately 50 mm depth at 1155 females appearing less vibrant than males (Andreone et h, she redirected excavation to an easterly direction so al., 2005; Glaw and Vences, 2007). Panther chameleons that the burrow now opened to the west (Fig. 1a). At are considered fully grown within one year, and their 1225 h, with the female still digging, she uncovered an life span typically ranges from 2–7 years. However, egg and began pushing it out of the hole with her back very few individuals will reach full maturity (Ferguson feet. By 1245 h, she had uncovered 11 eggs and fully or et al., 2004; Andreone et al., 2005). In fact, it has been partially removed them from the hole (Fig. 1b). At 1250 postulated that females seldom live longer than one year h, with the hole around 140 mm deep, the female turned in the wild, yet are known to exhibit high fecundity, with around to face outward from the excavated burrow and clutch sizes from 10–40 eggs and reproductive activity began laying eggs (Fig. 1c). She continued to lay eggs beginning at an age of around 6 mo with additional until 1415 h, at which point she returned to her prior clutches laid every 3 mo thereafter (Müller et al., 2004; pinkish colouration. She then began to slowly push the previously removed eggs back into the hole and onto her newly laid eggs (Fig. 1d). She then proceeded to backfill the clutches with the removed dirt, using both her front and hind limbs to push sand into the hole. This process took approximately 40 min, followed by 20 min 1 Institute for Conservation Research, San Diego Zoo Global, of patting down the substrate and covering any traces PO Box 120551, San Diego, California 92112, USA. 2 Department of Anthropology, Portland State University, PO that she had been there. By 1515 h the nest site was no Box 751, Portland, Oregon 97297, USA. longer visible and she moved back across the open- * Corresponding author. E-mail: [email protected] canopy grass and ascended into the canopy. 910 Timothy M. Eppley Figure 1. Excavation of egg clutch (a, b), deposition of new egg clutch (c), and back-filling both egg clutches (d) by a panther chameleon in Masoala National Park, northeast Madagascar. The basics of this observation are in-line with be an anti-predator strategy. There are a multitude of previously reported information on panther chameleon predators that feed on reptile eggs (e.g., Andreone et al., clutch laying. Nest construction typically takes a couple 2007), and if the first set of eggs was from a different of hours, with females depositing their eggs within individual or a different species, then by burying her an hour or two (Bolton and Abate, 2002). This highly own clutch beneath another, the female may have used unusual nesting account, however, raises a multitude those 11 eggs as an added layer of protection should of questions. Foremost, it is unclear whether the set of the clutches be discovered. This, however, works on eggs initially removed was from the same species or the unlikely presumption that, if the eggs were found, even the same individual. Although I did not measure a predator would become satiated eating the first clutch them, all eggs appeared to be approximately of the same and depart before consuming the second set of eggs. size, shape, and colouration. Also, the female changed If we are to presume that both egg clutches belonged directions while excavating the burrow, perhaps sensing to the same female, there are a couple of remarkable where the previous clutch had been laid. Considering insights provided by this account. First, the gravid female the concept that female panther chameleons have fixed returned to her nest site to lay additional eggs, exhibiting home ranges (Gehring et al., 2008), it is possible that spatial knowledge of her territory. Though I can only both clutches belonged to the same individual. speculate as to why the female returned to the same nest, If the first clutch was from a different species or it is possible that this particular site provides an ideal individual, this unusual egg-deposition event may ambient soil temperature for initiating development Evidence of spatiotemporal planning in a panther chameleon 911 of diapausing embryos / embryo survival, or may Ferguson, G.W., Murphy, J.B., Ramanamanjato, J.-B., Raselimanana, even be due to breeding site fidelity (i.e., maintenance A.P. (2004): The Panther Chameleon: Color Variation, Natural of natal philopatry; Andrews and Donoghue, 2004; History, Conservation, and Captive Management. Malabar, Florida, USA, Krieger Publishing Company. Refsnider and Janzen, 2010). Secondly, she removed Gehring, P.-S., Lutzmann, N., Furrer, S., Sossinka, R. (2008): the older eggs in order to lay new eggs beneath them, Habitat preferences and activity patterns of Furcifer pardalis exhibiting temporal knowledge about hatching time. (Cuvier, 1829) in the Masoala Rain Forest Hall of the Zurich By understanding that the older eggs would hatch first Zoo. Salamandra 44: 129–140. and disrupt the upper portion of the nest, burying the Glaw, F., Vences, M. (2007): Field Guide to the Amphibians and second clutch below them ensures additional protection Reptiles of Madagascar, Third Edition. Cologne, Germany, for the second clutch of eggs. Though circumstantial, Vences & Glaw Verlag. Müller, R., Lutzmann, N., Walbröl, U. (2004): Furcifer pardalis. to my knowledge this unusual observation provides the Das Panther Chamaleon. Münster, Germany, Natur und Tier- first evidence of spatiotemporal oviposition planning by Verlag. a chameleon. Rabearivony, J., Brady, L.D., Jenkins, R.K., Ravoahangimalala, O.R. (2007): Habitat use and abundance of a low-altitude Acknowledgements. Thanks to Jörg Ganzhorn, Julian Glos, and chameleon assemblage in eastern Madagascar. The Frank Glaw for their thoughtful discussions. This observation Herpetological Journal 17: 247–254. was made while undertaking fieldwork in northeast Madagascar Refsnider, J.M., Janzen, F.J. (2010): Putting eggs in one basket: as part of San Diego Zoo Global’s lemur conservation efforts. ecological and evolutionary hypotheses for variation in oviposition-site choice. Annual Review of Ecology, Evolution, References and Systematics 41: 39–57. Andreone, F., Guarino, F.M., Randrianirina, J.E. (2005): Life history traits, age profile, and conservation of the panther chameleon, Furcifer pardalis (Cuvier 1829), at Nosy Be, NW Madagascar. Tropical Zoology 18: 209–225. Andreone, F., Glaw, F., Randrianirina, J.E., Vences, M. (2007): Remarkable records of amphibians and reptiles on Madagascar’s central high plateau. Tropical Zoology 20: 19–29. Andrews, R.M., Donoghue, S. (2004): Effects of temperature and moisture on embryonic diapause of the veiled chameleon (Chamaeleo calyptratus). Journal of Experimental Zoology, Part A, Comparative Experimental Biology 301: 629–635. Bolton, J., Abate, A. (2002): Multigenerational captive reproduction of Furcifer pardalis and Furcifer oustaleti. Chameleon Information Network Journal 44: 5–10. Carpenter, A.I., Robson, O., Rowcliffe, J.M., Watkinson, A.R. (2005): The impacts of international and national governance changes on a traded resource: a case study of Madagascar and its chameleon trade. Biological Conservation 123: 279–287. Accepted by Angelica Crottini.