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which was hidden under the litter, we moved a leaf and acciden-
tally startled the Alsophis, which struck at us several times before
releasing the hawk and moving into the litter, revealing a super-
ficial head wound as it fled.

After release, the hawk stumbled on an apparently numbed
right leg and seemed unable to flex its right wing; upon return-
ing to the site approximately three hours later, however, we
observed the bird, seemingly unharmed, flying between trees.

Acknowledgements
We thank Bob Powell and Bob Henderson for providing com-

ments on this note. This observation was made while conduct-
ing research on Iguana delicatissima in Dominica. That project
is funded through the Center for Conservation and Research for
Endangered Species (CRES) at the Zoological Society of San
Diego.

Literature Cited
BirdLife International 2004. Buteo platypterus. In: IUCN 2007. 2007 IUCN

Red List of Threatened Species. <www.iucnredlist.org>.

Malhotra, A. and R.S. Thorpe. 1999. Reptiles & Amphibians of the Eastern
Caribbean. Macmillan Education, Ltd., Oxford and London, UK.

Normally diurnal West Indian anoles (Polychrotidae: Anolis)
are known to exploit insects attracted to artificial lights

well into the night (e.g., Perry and Fisher 2006, Henderson and
Powell 2009). Secondary exploitation of nocturnal anoles by a
typically diurnal predator, the Puerto Rican Racer (Alsophis por-
toricensis), has been reported on hotel grounds on Guana Island,
British Virgin Islands (Perry and Lazell 2000).

At 1915 h (transition to full dark) on 18 June 2008, we
observed a male Dominican Racer (Alsophis antillensis sibonius;
SVL 525 mm, tail 247 mm) in a foraging position at the base
of a light frequently used by a nocturnally active Dominican
Anole (Anolis oculatus). The observation occurred on the
grounds of the Sunset Bay Club at Batali Beach, on the leeward
coast of Dominica, Lesser Antilles.

Based on our experiences, exploitation of the night-light
niche has become commonplace among West Indian anoles
associated with urban areas and other situations in which artifi-
cial lighting is prevalent at night (e.g., hotels, resorts). However,
both situations in which snakes have been observed exploiting
the night-light niche (Guana Island, Batali Beach) have been
“snake-friendly”; that is, guests and personnel of the hotels are
instructed not to harm snakes that enter areas frequented by
humans. Under more typical circumstances (i.e., where snakes
would be killed or, at least, removed from the area), we doubt
that snakes would have the opportunity to learn to exploit this
potentially productive trophic niche.

Acknowledgements
Marcella and Roger Dutrieux Cools, owners of the Sunset Bay
Club tolerated our eccentricities. Mr. Arlington James, Forest
Officer, Forestry, Wildlife, and Parks Division, Ministry of

156 IGUANA  •  VOLUME 15, NUMBER 3  •  SEPTEMBER 2008 POWELL AND HENDERSON

A Dominican Anole (Anolis oculatus) exploiting the night-light niche
on the grounds of the Sunset Bay Club at Batali Beach, Dominica.

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Exploitation of the Night-light Niche 
by a Dominican Racer

Robert Powell1 and Robert W. Henderson2

1Department of Biology, Avila University, Kansas City, MO 64145, USA (robert.powell@avila.edu)
2Section of Vertebrate Zoology, Milwaukee Public Museum, Milwaukee, WI 53233, USA (henderson@mpm.edu)

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IGUANA  •  VOLUME 15, NUMBER 3  •  SEPTEMBER 2008 157DOMINICAN RACERS

Agriculture & the Environment, Commonwealth of Dominica,
was instrumental in issuing permits to conduct research in
Dominica and facilitated our efforts in myriad ways. Fieldwork
was funded by a grant from the National Science Foundation
(USA) to Robert Powell (DBI-0242589).

Literature Cited
Henderson, R.W. and R. Powell. 2009. Natural History of West Indian

Amphibians and Reptiles. University Press of Florida, Gainesville.

Perry, G. and R.N. Fisher. 2006. Night lights and reptiles: Observed and poten-
tial effects, pp. 169–191. In: C. Rich and T. Longcore (eds.), Ecological
Consequences of Artificial Night Lighting. Island Press, Washington, D.C.

Perry, G. and J. Lazell. 2000. Liophis portoricensis anegadae (NCN). Night-light
hunting. Herpetological Review 31:247.

Alsophis antillensis sibonius is endemic to Dominica, Lesser
Antilles. Although Schwartz and Henderson (1991)

described adults, thorough descriptions of juveniles have not
been published. During a June 2008 study conducted primarily
at Cabrits National Park, we made >160 observations of an
undetermined number of snakes. Included in the observations
were five juveniles, for four of which we collected and recorded
pattern data. The only previous description of the juvenile pat-
tern was by Parker (1933): “… an undulating dark vertebral
stripe, a narrow lateral line, and dark spots on the flanks and
hinder parts of the belly.”

The top of the head in juveniles is uniformly brown, dark-
ening laterally, with very dark brown to black lines extending

from the snout and through the eyes before blending into the
darker elements of the body pattern. Supralabials are white,
sometimes with faint specks of light brown or gray. Faint to
moderately distinct stippling occurs on infralabials, chin, and
throat.

Juveniles have distinct brown middorsal “saddles” faintly
outlined in black on a white to pale gray or tan ground color.
Most saddles on any one individual are in contact, forming a
continuous middorsal line with paired lateral extensions. These
saddles may be obliquely situated or offset, forming a wavy
(“zigzag”) line along at least portions of the dorsum. At least a
few saddles on each animal are isolated by pale ground color
extending across the middorsal line. On all juveniles examined,

Juvenile Pattern and Ontogenetic Pattern
Changes in Dominican Racers

Lauren A. White1 and Peter J. Muelleman2

1Environmental Science Program, Oklahoma State University, Stillwater, Oklahoma 74078, USA (lauren.a.white@okstate.edu)
2Department of Biology, Truman State University, Kirksville, Missouri 63501, USA (pjm563@truman.edu)

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A Dominican Racer (Alsophis antillensis sibonius) in a foraging position
at the base of a light such as that illustrated on the facing page. This
foraging posture, with the anterior portion of the body elevated at the
base of the light, is essentially similar to that observed in snakes at the
bases of tree trunks in more “natural” habitats (L.A. White and P.J.
Muelleman, pers. comm.).R

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