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forelimb and pushed the A. mutica off of the basking snag, thenclimbed to the location that the A. mutica had vacated. Shortlythereafter (ca. 30–45 sec), presumably the same A. mutica reemergedon the same snag below the G. flavimaculata. Soon afterthe A. mutica emerged, a second small G. flavimaculata female,similar in size to the first, emerged from the bank side of the snag.While she was climbing onto the snag, she placed her right forelimbon the carapace of the A. mutica, apparently prompting it tomove to another emergence point on the same snag (ca. 0.5 maway). After several minutes, the second G. flavimaculata vacatedthe log and then quickly reemerged and oriented itself behind thefirst G. flavimaculata.Also on 17 April 2007 (1530 h), an alternative strategy, avoidanceof a much larger interspecific, was observed by several G.flavimaculata. Upon approaching a 1.5 m long horizontal branchsizedsnag, several emydid turtles were observed by WS vacatingtheir basking locations before they could be identified. The snagwas watched (via spotting scope) from a distance to see if theturtles would reemerge. Within minutes, a large female G.flavimaculata (>15 cm CL) emerged from the lowest angle of thesnag/water interface and climbed approximately 15 cm up the snag.A large Pseudemys concinna (>20 cm CL) emerged behind the G.flavimaculata female and occupied the lowest emerged portion ofthe snag. After the emergence and ‘roadblock’ of the snag by theP. concinna, several more G. flavimaculata were observed swimmingaround the snag (heads emerged from the water). A secondlarge G. flavimaculata female climbed vertically up the channelside of the snag to a basking location about 0.75 m away from thefirst G. flavimaculata female. A third G. flavimaculata femaleexhibited the same vertical climbing behavior, except approachingfrom the bank side of the snag and choosing a position betweenthe first and second G. flavimaculata. It appeared that thesecond and third G. flavimaculata females used this technique,climbing a steeper, vertical angle, to get to a desired basking locationwhile avoiding encounters with the previous two occupantsof the snag.In the first observation, aggression appeared to be advantageousfor the larger G. flavimaculata females in order to obtain a favorablebasking location. However, in the second observation, thetwo female G. flavimaculata ‘climbers’ were smaller than the P.concinna, and therefore, may not have had the option of usingaggression to advance themselves to a favorable basking locality.These observations are supported by previous research that examinedaggressive interactions among four emydids: Trachemysscripta, Pseudemys concinna, Graptemys pseudogeographica, andGraptemys oauchitensis (Lindeman 1999. J. Herpetol. 33:214–219). Lindeman noted that aggressive interactions were “won”70% of the time by larger turtles, which is consistent with ourobservations and interpretations of G. flavimaculata behavior.Submitted by WILL SELMAN and CARL QUALLS, Departmentof Biological Sciences, Box 5018, University of SouthernMississippi, Hattiesburg, Mississippi 39401, USA (e-mail:will.selman@usm.edu).GRAPTEMYS FLAVIMACULATA (Yellow-blotched MapTurtle). FORAGING BEHAVIOR. The Graptemys flavimaculatais a freshwater aquatic turtle that is endemic to the PascagoulaRiver system of southern Mississippi, USA (Ernst et al. 1994.Turtles of the United States and Canada. Smithsonian InstitutePress, Washington, D.C. 578 pp.). R. J. Brauman and R. A. Seigel(unpubl. report) suggest that the primary food items of G.flavimaculata are insects, sponges, mollusks, and algae. They concludedthat the presence of algae was due to secondary ingestion,rather than being a primary food item. However, very little is knownabout the foraging behavior of this species. Here we report twoseparate observations of female G. flavimaculata foraging on algae-coveredsubmerged logs.On 2 June 2006 (1650 h), a female G. flavimaculata was observed(by WS) ca. 0.3 m deep in a swift-flowing riffle section ofthe Leaf River (Forrest County, Mississippi) foraging on an algaecoveredlog. The female was grasping the downstream side of thelog with her forelimbs as she appeared to “graze” on the periphyton.After brief observation, the female was captured with a dipnet for marking and measurement (16.7 cm straight-line carapacelength, 740 g); she had some filamentous algae in her mouth at thetime of capture.The second observation (also by WS) occurred on 30 August2006 in the Lower Pascagoula River (Jackson County, Mississippi)at 1340 h. An adult female G. flavimaculata was observed from2–2.5 m away (the presence of the boat did not appear to affecther behavior) “grazing” on the periphyton of a submerged log, inthe same manner as noted before on the Leaf River. Her forelimbswere gripping the log as she foraged on the bank side. While feeding,she would quickly protrude her head, bite, and pull with herjaws, sometimes doing a “pushup” motion with her forelimbs toassist in tearing the algae off the submerged log. Feeding appearedat random without a side-to-side or a top-to-bottom order. Thisforaging behavior occurred in water ca. 20–80 cm deep and continuedas the turtle moved ca. 1.5 m along the log, sometimesholding onto the log with all four legs. After continuously feedingfor ca. 15 minutes, the turtle surfaced (apparently for air), noticedits observer and quickly swam away. Inspection of the log showedlittle evidence of aquatic insects, but it was covered by a verythick layer of short growth filamentous algae. Also, while watchingthe adult female, a juvenile female G. flavimaculata was alsoseen foraging in a similar manner for the first 3–5 minutes of theobservation.During both of these observations it could not be ascertained ifthe turtles were feeding directly on algae or on macroinvertebrateswithin the algae. Lahanas (1982. Unpubl. M.Sc. thesis, AuburnUniversity) found that the diet of a closely related species, G.nigrinoda, had 28% and 41% average volume plant material forfemales and males, respectively. Similar behavior hás been notedin G. oculifera, another closely related species (R. L. Jones, pers.comm.). Thus, based on the above observations, it is plausiblethat G. flavimaculata is omnivorous and supplements its diet withplant material. More study is needed to determine if this speciesconsumes algae as a primary component of the diet, or if algae issecondarily ingested during foraging for macroinvertebrates.Submitted by WILL SELMAN and CARL QUALLS, Departmentof Biological Sciences, Box 5018, University of SouthernMississippi, Hattiesburg, Mississippi 39401, USA (e-mail:will.selman@usm.edu).Herpetological Review 39(2), 2008 215