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Evidence that female anacondas may eat males, likely during the breeding season
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The data verify the activity pattern reported by Rodda et
al.
(op.
cit.), support an activity pattern hypothesized by Gibbons and Sem-
litsch (op. cit.) for tropical snakes
in
seasonal environments and
suggest that seasonal activity patterns can be discerned for
~ome
species
of
tropical snakes using highway mortality statistics.
Submitted by
MICHAEL
JAMES
McCOID,
2121 Ivy Street,
Port Charlotte, Florida 33952, USA (e-mail: mccoid@isni.net),
and
REBECCA
A. HENSLEY, Fish and Wildlife Conservation
Commission, Florida Marine Research Institute, 1481 Market
Circle, Port Charlotte, Florida 33953, USA.
BOTHROPS CAMPBELL/ (Campbell's Lancehead).
DIET
and
REPRODUCTION.
The
poorly
known
pitviper
Bothrops
campbelli Freire
1991
inhabits lower montane wet forests and cloud
forests along the western versant
of
the Cordillera Occidental
of
the Andes in Colombia and Ecuador (Kuch 1997. Bull. Zool. No-
menclature 54:245-249). Here we provide the first data on diet
and reproduction in this species. A large female
B.
campbelli (SVL
920 mm, tail length 137 mm), collected in Huagal,
Canton
Pallatanga, Province
of
Chimborazo, Ecuador ( 1500 m elevation;
ca. 79°02'W, 2°10'S) on 29 April 1992 by A. Lema, contained a
partly digested, rat-sized rodent. In addition, this snake contained
36 follicles measuring 10 mm in diameter, nine
of
5-10
mm, and
about 50
of
2-4
mm. The specimens are deposited in the herpeto-
logical collection
of
the Instituto Nacional de Higiene y Medicina
Tropical, Guayaquil (INHMT 2622). The reproductive potential
of
this
B.
campbelli resembles that
of
a large
B.
microphthalmus
(750 mm SVL), which contained 36 embryos (Kuch and Freire
1995. Herpetozoa 8:81-83). Bothrops microphthalmus is found in
comparable habitat and altitude in the Amazonian versant
of
the
Andes in Colombia, Ecuador, and Peru.
Submitted by
ANTONIO
FREIRE,
Departamento Ofidios, In-
stituto Nacional de Higiene y Medicina Tropical
"Leopoldo
lzquieta Perez," Casilla 3961, Guayaquil, Ecuador, and
ULRICH
KUCH, Sektion Herpetologie, Forschungsinstitut Senckenberg,
Senckenberganlage 25, D-60325 Frankfurt, Germany (e-mail:
kuch@stud.uni-frankfurt.de
).
BOTHROPS NEUWIEDI PAULOENSIS (Jararaca Rabo-de-
osso). PREDATION. Records
of
predation on neotropical snakes
are scarce. Here we report predation
on
Bothrops neuwiedi
pauloensis by the burrowing owl Athene cunicularia (Aves:
Strigidae
).
The observation occurred on 7 September 1998 at 2020
h in Parque Nacional da Emas (18°06'S, 52°55'W,
760-880
m
elev.), municipality ofMineiros, Goias, Brazil. Bothrops neuwiedi
pauloensis occurs in high densities in open habitats in the park.
The predation occurred in a recently burned area
of
"campo limpo"
(open grasslands). The snake (young male, 365 mm SVL, 65
mm
tail length) was found decapitated on the ground, where the owl
left it as we approached. The snake was still showing motor re-
flexes, indicating that it had just been attacked. A termite mound
(1.6 m high), 7 m from the prey, was apparently used by the owl as
a perch, similar to the hunting tactics described by Martins and
Egler (1990. Rev. Bras. Biol. 50:579-584). There were many bird
droppings on the ground near this hunting perch, indicating fre-
quent use
of
the site by the predator. Snakes are uncommon prey
items
of
Athene cunicularia, and no reports
of
predation
on
B.
neuwiedi are available (Clark et al. 1997. J. Raptor Res. Report
9:145-170). The snake was deposited in the herpetological col-
lection
of
the Instituto Butantan (IB 59909).
Submitted
by
PAULA
H.
VALDUJO
and
CRISTIANO
NOGUEIRA,
Laborat6rio de Herpetologia, Instituto Butantan,
Av.
Vital Brasil, 1500, CEP 05503-900, Sao Paulo, SP, Brazil, and
Depto. de Ecologia Geral, Instituto de Biociencias, Universidade
de Sao Paulo,
CP.
111461, CEP 05508-900, Sao Paulo,
SP,
Brazil
(e-mail: paulahv@ib.usp.br).
CROTALUS SCUTULATUS SCUTULATUS (Mojave Rattle-
snake).
DEFENSIVE
BEHAVIOR. Neck spreading is a defen-
sive display that previously has been reported in rattlesnakes only
for Crotalus scutulatus salvini (Glenn and Lawler 1987. Herpetol.
Rev.
18:
15-16). An adult
C.
s.
scutulatus ca. 1 m totallength (TL)
was AOR at 1700 h,
13
October 1996, on Hwy 54,
30
mi north
of
Van
Horn, Culberson County, Texas, USA. A photograph
of
its
defensive display showed the neck immediately posterior to the
head to be spread laterally and the cervical spine to be straight and
aligned with the head (Fig. 1). Based on an estimated
SVUTL
proportion, this individual appears to be a male.
FIG.
1.
Defensive display
of
Crotalus
s.
scutulatus, illustrating the neck
spreading described in the text.
Submitted
by
JAMES
F.
W.
BROWN,
WENDY
M.
MARDEN,
4305 North Sanders Road, Tucson, Arizona, 85743,
USA, and DAVID L. HARDY, SR., 585 South Main Avenue,
Tucson, Arizona, 85701-2229, USA.
EUNECTES MURINUS (Green Anaconda).
CANNIBALISM.
One instance
of
cannibalism in the green anaconda (Eunectes
murinus) has been reported in the literature
(O'Shea
1994. Herpe-
tol. Rev. 25:124). This observation involved a female eating a
smaller conspecific
of
unknown sex. Here, we report three other
cases
of
female anacondas eating conspecifics. These observations
occurred during the breeding (dry) season in the Venezuelan ll-
anos, Distrito Munoz, Apure State (7°30'N, 69°18'W).
Herpetological Review
31
(I), 2000 45
FIG.
1.
Female anaconda regurgitating a male (note the hemipenis).
Photograph courtesy
of
Tony Rattin.
The first observation involved a large female (434.7
cm
total
length [TL],
40
kg) that was caught 27 April 1995 next to a breed-
ing aggregation (Rivas 1999. Life History
of
the Green Anaconda
with Emphasis on its Reproductive Biology. Ph.D. dissertation.
Univ. Tennessee, Knoxville
..
269 pp.), but not participating in it.
The snake had the engorged stomach that indicates a recent meal.
After being put in a cage, she regurgitated a male anaconda ( 42
cm
tail length, 283
cm
estimated TL, 5.7 kg, Fig. 1).
On
28 May
1996, at the end
of
the breeding season, we discovered another
female constricting a medium-sized male (230
cm
TL; 5 kg). The
male was dead by the time we found it, and the female (370
cm
estimated TL) managed to escape when we tried to capture her.
Judging by the girth and overall condition
of
the snake, she was
most likely breeding, and probably had just recently finished her
mating activity. Lastly, on
18
March 1997 we collected a fecal
sample that contained anaconda scales. The sample was from a fe-
male anaconda (300 cm TL, 14.8 kg) that was breeding that season.
All four records
of
cannibalism in green anacondas involve can-
nibalistic females, and the sex
of
the cannibalized individual has
been male in the two instances in which sex could be determined.
This asymmetry is probably a consequence
of
the strong sexual
size dimorphism found in the species, with females much larger
than males (Rivas,
op.
cit.). Green anacondas concentrate around
the more permanent water sources during the dry season, and at
this time breeding occurs (Rivas,
op.
cit.). Male anacondas look-
ing for water and/or breeding females appear to be especially vul-
nerable to cannibalism by females. After mating, pregnant females
do not eat for seven months (Rivas,
op.
cit.).
It
is possible that
breeding females eat their mating partners in order to help them
survive the long fast associated with pregnancy.
We thank The Wildlife Conservation Society and The National
Geographic Society for funding this research, and COVEGAN
for allowing us to work on their
~and.
We also thank G. M.
Burghardt for comments on the manuscript.
JESUS
A. RIVAS, Graduate Program in Ethology, Department
of
Ecology & Evolutionary Biology, University
of
Tennessee,
Knoxville,
Tennessee
37996-0900,
USA
(e-mail:
anaconda@prodigy.net), and
RENEE
Y.
OWENS, Vegueros Wild-
life Biology, 348 Field Street, Brockton, Massachusetts 02302,
USA. Current address for correspondence (JAR and RYO) : 17126
Lawson Valley Road, Jamul, California 91935, USA.
46 Herpetological Review 31(1), 2000
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