Herpetological Review 38(1), 2007 71

ent directions. After the pair separated, the formerly paired malegrabbed No. 1 and began amplexing him, even though he struggledto escape. At this point, all three frogs were captured and mea-sured. Over the period of observation, the paired frogs initiallytraveled ca. 2 m.

A second amplectic pair (male 53 mm SVL, 12.8 g; female 74.4mm SVL, 35.5 g), observed entering the oviposition area at 1055h, just after capture and release of the frogs described above, wasalso followed closely by two additional male frogs (No. 2: 54.0mm SVL, 11.0 g; No. 3: 67.5 mm SVL, 20.0 g). These males be-haved in a manner similar to No. 1, but approached much moreclosely and frequently made contact with the pair. On at least 10occasions, they grappled at the paired male or the hind leg of thefemale. Usually, the female would forcefully kick the intruder(s)away, but occasionally both amplectic partners or rarely, only themale, would do the kicking. The unpaired males also continuouslyrushed, grabbed, and amplexed one another. Rushes would be madefrom a near touching position to distances > 45 cm away, withsmaller males grabbing larger males and vice versa. Often, re-lease following an amplectic grab would be immediate, without asound. However, for at least one third of (> 30) such grabs, onemale amplexed a second male for between 30 sec and 2 min, evenwhile the other forcefully tried to escape, swimming a meter ormore and flipping upside down (often with the frogs’ bright yel-low-and-white undersurfaces visible for at least 30 sec). Theseentire sequences occurred without any apparent vocalization. Onat least three occasions, one male even grabbed another male fac-ing backwards (i.e., the frogs were facing opposite directions).Although individual males would swim to the surface regularly(more frequently than the male/female pair) to gulp air (and thenswim quickly back to the bottom to hide), pairs of males were alsoobserved to surface together to gulp air on multiple occasions.This behavior continued for 3 hours, until the frogs were capturedand measured.

Non-vocal competition for females is known for a number ofanuran species, and is most common among explosive breeders(Wells 1977a. In Taylor and Guttman [eds.], The ReproductiveBiology of Amphibians, pp. 233–262. New York, Plenum Press;Wells 1977b. Anim. Behav. 25:666–693). Over five years of study,the R. boylii at this location have completed most of their breed-ing activity within a week. At breeding sites, males outnumberfemales by an average of 7 to 1, and observations of breedingfrogs indicate that females are amplexed by the first male theyapproach (CJR, unpubl. data). Because frogs in male-only aggre-gations often grab one another, tactile identification (rather thanauditory or visual identification) of a suitable partner appears tobe an important cue for stimulating amplexus (Noble and Aronson1942. Bull. Am. Mus. Nat. Hist. 80:127–142; Wells 1977b, op.cit.).

While physical displacement of a competing male is obvious,male competition may not involve much, if any direct contact. Inparticular, the behavior performed by male No. 1 (holding his ventover freshly laid eggs) strongly resembles the “clutch piracy” be-havior of R. temporaria, in which pirate males fertilize the eggs ofanother frog pair, either during or after laying (Vieites et al., op.cit.). Confirmation of this hypothesis requires genetic data, butour observations imply that such competitive behavior may bemore widespread among ranid frogs than previously thought.

Submitted by CHRISTOPHER J. ROMBOUGH, P.O. Box365, Aurora, Oregon 97002-0365, USA (e-mail:rambo2718@yahoo.com); and MARC P. HAYES, WashingtonDepartment of Fish and Wildlife, Habitat Program, 600 CapitolWay North, Olympia, Washington 98501-1091, USA (e-mail:hayesmph@dfw.wa.gov).

RANA CATESBEIANA (American Bullfrog). MORTALITY. On25 Aug 2005, I found a recently deceased adult male Bullfrog(snout–urostyle length ca. 16.5 cm) with the posterior half of an11.5 cm TL Brown Bullhead (Ameirus nebulosus) protruding fromits mouth. I made this observation along the edge of a drying poolin a blackwater creek swamp on Fort Stewart Military Installa-tion, Long Co., Georgia, USA. The 4 × 6 m turbid and fetid poolwas littered with the carcasses of dozens of Brown Bullheads andcentrarchids that had recently died, likely due to anoxic condi-tions. A few live fish occasionally surfaced to gulp air. As seen inFig. 1, the frog evidently choked on the fish while attempting toswallow it. Whether the dorsal or pectoral spines of the fish pre-vented the frog from swallowing the fish or whether the frog chokedsolely because of the large size of the prey is unknown. To myknowledge this is the first observation of a Bullfrog choking whileattempting to prey on a bullhead.

I thank John G. Palis for reviewing this note.

Submitted by DIRK J. STEVENSON, DPW-ED, Fish andWildlife Branch, Fort Stewart, Georgia 31314, USA; e-mail:stevensond@stewart.army.mil.

TESTUDINES

PHRYNOPS HILARII (Hilaire’s Side-necked Turtle). FEEDINGBEHAVIOR. Phrynops hilarii posseses a prominent pair of bar-bels in the gular region that function as mechanoreceptors and areused during mating behavior (Bager 1997. M.S. Thesis.Universidade Federal do Rio Grande do Sul. Rio Grande do Sul.

FIG. 1. Adult American Bullfrog (Rana catesbeiana) that died whileattempting to eat a Brown Bullhead (Ameirus nebulosus).

72 Herpetological Review 38(1), 2007

Brazil. 110 pp.; Winokur 2005. J. Morphol. 172:59–74; Legler1993. In Glasby et al. [eds.], Fauna of Australia, vol. 2, pp. 108–119. Canberra). The barbels are beige in color, matching the turtle’sgular coloration, but have a conspicuous black ring at the base.Here we present a description of the species’ use of the barbels infeeding, specifically in attracting and capturing fishes. Captive-hatched Phrynops hilarii hatchlings (mean carapacelength = 42.4 ± 3.25 mm; N = 111) were kept in a 500-L aquarium(30–40 turtles per tank) with a water depth of 50 cm, a small dryarea, and a quantity of floating aquatic macrophytes. Hatchlingswere fed live fish and pieces of beef. Thirty juvenile lambari(Astyanax sp.), a characid fish, with a mean length of 3.1 ± 0.5cm, were placed in the tank weekly. The P. hilarii hatchlings were observed using a unique feedingstrategy whereby they aligned themselves with submerged Pistiastratiotes roots or stalks or on the terrarium substrate itself by ex-tending their anterior limbs forward and hind limbs backward. Theirnecks remained fully extended, which is contrary to the strategyused by “fishing” Chelus fimbriatus, which keep the neck par-tially contracted (Pritchard 1984. Symp. Zool. Soc. London 52:87–110; Lemell et al. 2002. J. Exp. Biol. 205:1495–1506). The headis jerked in short and quick movements, which causes the barbelsto move. It was observed that the black circle at the barbel’s basegives an impression of discontinuity between the turtle’s gular re-gion and the barbel, hence it may resemble a small invertebrate toa passing fish. Juvenile fish that approach a Phrynops hilariihatchling’s head and try to bite at the barbels are often captured,though the efficiency of this strategy was not quantified. The fish were not quickly swallowed, probably due to their com-paratively large size. A hatchling P. hilarii that captured a fish wassoon approached by other hatchlings, starting a competition forthe resource involving agonistic behavior. Such behavior includedbites to the anterior and posterior limbs. The monitored hatchlings did not have any contact with juve-nile or adult exemplars, making it unlikely that the observed feed-ing behaviors were learned. Systematic observations in a naturalenvironment have not been made, but on several occasions weobserved the same postures in juvenile and adult specimens sub-merged in rivers and wetlands, though a complete behavioral se-quence with prey ingestion has not yet been noted.

Submitted by ALEX BAGER, LAURO J. C. BARCELLOS,and SÉRGIO R. N. PIEDRAS, Universidade Católica de Pelotas.Laboratório de Manejo e Conservação Ambiental, Rua Félix daCunha, 412, Pelotas, RS, 96010 000, Brazil (e-mail:abager@uol.com.br).

RHINOCLEMMYS FUNEREA (Black Wood Turtle). REPRO-DUCTION. The reproductive biology of R. funerea is inadequatelyknown. Courtship and mating behavior, and egg-laying have beendescribed by Iverson (1975. J. Herpetol. 9:249–250) and Merchánand Mora (2000. Reptilia 26:31–38). Nevertheless, the reproduc-tive season, clutch size, and egg and hatchling size are poorlyknown. This note provides additional data on reproduction in CostaRica. Between November 1999 and December 2001 we found nineegg clutches of R. funerea in the Reserva Zoo Ave (Alajuela Prov-ince, Costa Rica). Mean clutch size was 4.3 eggs (range 1–7, SD =

1.94). Egg laying occurred between May and October, with a peakin May (44.4% of the sample). The incubation period ranged from81 to 106 days (mean 92.3) at a temperature of 28ºC. Twenty-fiveof 40 eggs produced hatchlings. Data for 40 eggs are as follows.Mean mass = 49.6 g (range 37.3–60.0 g, SD = 6.0); mean length =64.2 mm (range 55.3–76.1 mm, SD = 5.5); mean width = 34.9mm (32.0–38.1 mm, SD = 1.3). Hatchling measurements are shownin Table 1.

We thank Zoo Ave Reserve for permission to study the R. funerea.The Spanish International Cooperation Agency (AECI-ForeignOffice, Spain) provided financial support to Manuel Merchán inCosta Rica.

Submitted by MANUEL MERCHAN F., Asociación Chelo-nia, Aristóteles, 3-2º B, 28027 Madrid, Spain (e-mail:manuelmerchan@yahoo.com); and RAUL FOURNIER, ReservaZoo Ave., Apdo. 1327-4050 Alajuela, Costa Rica.

CROCODYLIA

CROCODYLUS ACUTUS (American Crocodile). MIGRATION.American Crocodiles require an elevated, well-drained substratefor nesting (Mazzotti 1989. Bull. Mar. Sci. 44:220–228). In Florida,human-made nesting areas along canal banks (berms) at Croco-dile Lake National Wildlife Refuge, East Cape Canal in EvergladesNational Park (ENP), and the cooling canal system at Turkey PointPower Plant provide near ideal nesting conditions, with year-roundhabitat adjacent or in close proximity to nesting sites. In contrast,nesting areas and nursery habitat in Florida Bay within ENP areoften separated by kilometers, necessitating migrations by femalesto nest sites (Kushlan and Mazzotti 1989. J. Herpetol. 23:1–7).Mazzotti (1983. The Ecology of Crocodylus acutus in Florida.PhD dissertation, The Pennsylvania State University, UniversityPark, Pennsylvania. 161 pp.) reported seasonal movements of 5–15 km from year-round habitat to nesting beaches. Crocodylusacutus at other locations across its range have been suspected toexhibit this behavior as well; however, to date no such reportshave been published. Here we report the longest distance recordedyet for migration of one female C. acutus to a nest site.

During the 2003 nesting season, a crocodile nest was reportedon Lower Matecumbe Key (24°52'30.4"N, 80°41'54.8"W, datum:WGS84; elev. 0.5 m) in the yard of a private estate. On 22 Sep-tember 2003, the nesting female crocodile (272 cm total length,70 kg) was captured along with nine hatchlings in a pond adjacentthe nest. All individuals were measured, weighed and given a

TABLE 1. Data on 25 hatchlings of Rhinoclemmys funerea. Weight ingrams, rest of measures in millimeters. St. Dev: Standard Deviation. SCL:Straight Carapace Length. SCW: Straight Carapace Width. SPL: StraightPlastron Length. SPW: Straight Plastron Width.

N Mean Minimum Maximum St. Dev.

Weight 25 32.4 24.9 38.5 4.12

SCL 15 56.5 50.8 65.0 3.75

SCW 15 48.0 43.6 54.7 3.17

SPL 15 50.3 44.7 58.5 4.00

SPW 15 39.7 35.4 44.9 2.65

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