Tag Archives: Anolis pulchellus

Predation of a Gecko by Anolis pulchellus in the British Virgin Islands

In the most recent issue of Herp Review, Anole Annals stalwarts Kevin de Queiroz and Jonathan Losos documented their account of observing an adult female grass-bush anole (Anolis pulchellus) consume a dwarf gecko (Sphaerodactylus macrolepis) on Guana Island, British Virgin Islands. The authors share their detailed report below:

Many primarily insectivorous lizards will eat other vertebrates on occasion, a behavior that has been reported in many species of Anolis. One unifying generality is that such carnivory is size structured, with the predator usually being substantially larger than the prey (Gerber 1999. In Losos and Leal [eds.], Anolis Newsletter V, pp. 28–39. Washington University, Saint Louis, Missouri). Not surprisingly, reports of anole carnivory pertain primarily to middle-sized and larger anoles. Here we report carnivory by a small anole of the species A. pulchellus. To our knowledge, this is the first instance of carnivory reported for this species and one of few for any similar-sized anole (the record noted by Henderson and Powell 2009. Natural History of West Indian Reptiles and Amphibians. University Press of Florida, Gainesville, Florida. 495 pp. is based on the observations reported here).

Fig. 1. Female Anolis pulchellus in the process of ingesting a Sphaerodactylus macrolepis.

Fig. 1. Female Anolis pulchellus in the process of ingesting a
Sphaerodactylus macrolepis.

We observed a female A. pulchellus (SVL ca. 38 mm) capture and consume a Sphaerodactylus macrolepis (SVL ca.18 mm) in the leaf litter at approximately 1430 h on 25 September 2006, on Guana Island, British Virgin Islands, near the head of the Liao Wei Ping Trail at roughly 18.47916°N, 64.57444°W (WGS 84). The anole jumped from a low perch (ca. 20 cm above the ground) to the ground and bit the gecko, which escaped and fled 15–20 cm to the opening of an ant nest. The anole attacked the gecko again, seized it in its mouth and carried it approximately 10 cm up a vine, a distance of 15–20 cm from the site of attack. Initially, the anole held the gecko upside down (i.e., dorsal surface facing down), biting it between the fore and hind limbs on the left side. Eventually the anole worked its grasp posterior to the base of the tail, still on the left side. At this point, parts of both the base of the tail and the left hind limb were in the anole’s mouth (Fig. 1). The anole then manipulated the gecko so that it was no longer upside down, but rotated about its long axis by roughly 90 degrees (the ventral surface of the gecko was then oriented forward relative to the anole) at which point it was biting the gecko at the base of the tail and possibly by the left hind limb; the anole eventually manipulated the gecko so that it held it tail-first in its mouth, dorsal side up, at which point the anole proceeded to ingest the gecko tail first (during this time, the tail itself broke off and was carried away by ants, which had been biting the gecko in several places since shortly after it was
captured by the anole). Total time from capture to complete ingestion was approximately five minutes.

Predation on Sphaerodactylus geckos has been reported in anoles of only a few species, none of which are as small as Anolis pulchellus (Henderson and Powell 2009. Natural History of West Indian Reptiles and Amphibians. University Press of Florida, Gainesville, Florida. 495 pp.). However, given the size discrepancy between the lizards in these two clades and their extensive coexistence across the Caribbean, we suspect that such interactions may occur with some frequency. Moreover, the high population densities of some Sphaerodactylus geckos (e.g., Rodda et al. 2001. J. Trop. Ecol. 17:331–338) and the diurnal activity of several species (Allen and Powell 2014. Herpetol. Conserv. Biol. 9:590–600) suggest that they may be important prey items for anoles.

References
Allen, K.E. and Powell, R., 2014. Thermal biology and microhabitat use in Puerto Rican eyespot geckos (Sphaerodactylus macrolepis macrolepis). Herpetological Conservation and Biology, 9(3), pp.590-600.
Gerber 1999. In Losos and Leal [eds.], Anolis Newsletter V, pp. 28–39. Washington University, Saint Louis, Missouri
Henderson and Powell 2009. Natural History of West Indian Reptiles and Amphibians. University Press of Florida, Gainesville, Florida. 495 pp.
Rodda, G.H., Perry, G.A.D., Rondeau, R.J. and Lazell, J., 2001. The densest terrestrial vertebrate. Journal of Tropical Ecology, 17(02), pp.331-338.

Fill In The Blank: Obscure Anole Life History Traits

In collaboration with the Conservation Biology course taught by Dr. Karen Beard here at Utah State University, where I am a Ph.D. student, I have been involved in gathering life history data on ~400 species of reptiles that have been introduced outside of their native ranges for an analysis of how life history traits (e.g., diet, fecundity, longevity) interact with other factors to influence the likelihood of successful establishment. Appendix A of Fred Kraus’ 2009 book Alien Reptiles and Amphibians is the source of the species list we are using, and included in this analysis are 26 species of Anolis. This is where you come in.

First, we coded all anoles as (i) sexually-dichromatic, (ii) diurnal, (iii) non-venomous, (iv) oviparous, (v) omnivores that lack (vi) temperature-dependent sex determination and (vii) parthenogenesis. Is anyone aware of any exceptions to these seven generalizations?

Second, we searched for data on clutch size, clutch frequency, incubation time, and longevity. The Anole Classics section of this site and the Biodiversity Heritage Library were particularly useful. After conducting what I feel to be a pretty thorough literature scavenger hunt, I am forced to conclude that some of these data simply do not exist at the species level for all of the species we’re interested in, or are not explicitly stated in a way that is obvious to a non-anole-expert. Of course, there is a lot of literature, including many books that I don’t have access to, and there are also lots of credible observations that don’t get published. I’m hoping that some of the readership here can help fill in at least some of the blanks in the table below. As one member of the team, I did not collect all of the data that are filled in myself, nor have I personally vetted every value, so if you spot an error please do point it out.

Two important points:

  1. Many environmental factors obviously influence the life history parameters of our beloved and wonderfully plastic reptiles, so we appreciate that many of these values would be better represented by ranges and are dependent on latitude, altitude, climate, and many other factors. Where a range is published, we are using its median value.
  2. I should also emphasize that, because of the large size of this study and the diversity of taxa included (ranging in size from giants like Burmese Pythons, Nile Crocodiles, and Aldabra Tortoises to, well, anoles and blindsnakes), it is more important for the data to reflect the relative values of these life history parameters across all anoles (and all reptiles) than it is to specifically and precisely represent all known variation within a given species of anole.

Without further ado (for your enjoyment, and because I know from my own blog that nobody reads posts lacking pictures, I’ve embedded an image of each species):

Species Median clutch size Median clutches per year Incubation time (days) Maximum longevity (months)
A aeneus
A. aeneus
2
A baleatus
A. baleatus
A bimaculatus
A.bimaculatus            
2 43 84
A carolinensis
A. carolinensis
1.15 6  41.5 65
A chlorocyanus
A.chlorocyanus
1 18
A conspersus
A. conspersus
1
A cristatellus
A. cristatellus
2.5 18 83
A cybotes
A. cybotes
1 18 45
A distichus
A. distichus
1 16 45.5
A equestris
A. equestris
1 1 48 149
A extremus
A. extremus
A ferreus
A. ferreus
1 18
A garmani
A. garmani
1.5 18 67
A grahami
A. grahami
1
A leachii
A. leachii
A lineatus
A. lineatus
A lucius
A. lucius
1 3.5 60
A marmoratus
A. marmoratus
2  50
A maynardi
A. maynardi
A porcatus
A. porcatus
1 18 63.5
A pulchellus
A. pulchellus
1
A richardii
A. richardii
1
A sagrei
A. sagrei
2 20  32 22
A stratulus
A. stratulus
A trinitatis
A. trinitatis
2  50
A wattsi
A. wattsi
1

Thanks in advance. I think this is a great blog and I hope to post something more interesting on here soon.