Iguana b&w text IGUANA • VOLUME 15, NUMBER 3 • SEPTEMBER 2008 177CONSERVATION RESEARCH REPORTS Non-native Fishes Threatening Hellbenders in Missouri The introduction of non-native fishes often results in the local extinction of native amphibians due to a lack of evolu- tionary history and resultant minimally- adapted antipredator behaviors toward the introduced fishes. Populations of Hellbenders (Cryptobranchus alleganien- sis) in Missouri have declined consider- ably since the 1980s, coinciding with a rapid increase in non-native trout intro- ductions for recreational angling. GALL (2008. Unpubl. M.S. Thesis, Missouri State University, Springfield) examined Hellbender and fish predator-prey inter- actions by: (1) examining the foraging behavior of predatory fishes in response to a Hellbender secretion; (2) comparing the number of secretion and control- soaked food pellets consumed by trout; and (3) comparing the response of larval Hellbenders to chemical stimuli from introduced (trout) and native fish preda- tors. Brown Trout, Walleye, and large Banded Sculpins responded to Hellbender secretions with increased activity, whereas small Banded Sculpins responded by decreasing activity. In addi- tion, Brown Trout ingested more Hellbender secretion-soaked food pellets than control pellets, whereas Rainbow Trout expelled secretion-soaked food pel- lets. Finally, larval Hellbenders exhibited weak fright behavior in response to chemical stimuli from nonnative trout relative to their responses to native preda- tory fish stimuli. These combinations of responses indicate that predation by non- native fishes may be a plausible hypothe- sis for the decline of Hellbender popula- tions in Missouri. Effects of Converting Dry Tropical Forest to Agricultural Mosaics SUAZO-ORTUÑO ET AL. (2008. Conserva- tion Biology 22: 362–374) explored the impact of forest conversion to agricul- tural mosaic on anuran, lizard, snake, and turtle assemblages in Neotropical dry forests. Over two years, the authors sam- pled six small watersheds on the western coast of Mexico, three conserved and three disturbed. The disturbed water- sheds were characterized by a mosaic of pastures and cultivated fields (corn, beans, squash) intermingled with patches of different successional stages of dry for- est. In each watershed, they conducted 11 diurnal and nocturnal time-con- strained searches in ten randomly estab- lished plots. We considered vulnerability traits of species in relation to habitat modification. Eighteen anuran, 18 lizard, 23 snake, and three turtle species were recorded. Thirty-six species (58%) occurred in both forest conditions, and 14 (22%) and 12 species (19%) occurred only in the conserved and disturbed sites, respectively. Assemblages responded dif- ferently to disturbance. Species richness, diversity, and abundance of lizards were higher in disturbed forests. Anuran diver- sity and species richness were lower in disturbed forest, but abundance was sim- ilar in both forest conditions. Diversity, richness, and abundance of turtles were lower in disturbed forest. The structure and composition of snake assemblages did not differ between forest conditions. Species were considered disturbance-sen- sitive if their abundance was significantly less in disturbed areas. Four anuran (22%), two lizard (11%), and three tur- tle (100%) species were sensitive to dis- turbance. No snake species was sensitive. The decline in abundance of distur- bance-sensitive species was associated with the reduction of forest canopy cover, woody stem cover, roots, and litter-layer ground cover. Anuran species with small body size and direct embryonic develop- ment were especially sensitive to forest disturbance. An important goal for the conservation of herpetofauna should be the determination of species traits associ- ated with extinction or persistence in agricultural mosaics. Reptilian Road Mortality in Illinois Roads have numerous negative ecological effects on terrestrial fauna, and vehicular mortality can have significant demo- graphic consequences for some species. SHEPARD ET AL. (2008. Copeia 2008: 350–359) studied road mortality of rep- tiles around Carlyle Lake, Clinton County, Illinois, USA, from April 2000 through November 2002, to assess the impact of vehicular traffic and identify C O N S E R V A T I O N R E S E A R C H R E P O R T S Populations of Hellbenders (Cryptobranchus alleganiensis) in Missouri have declined con- siderably since the 1980s, coinciding with a rapid increase in non-native trout introduc- tions for recreational angling. TH ER ES A C R O W , M IS SO U R I S TA TE U N IV ER SI TY Ameiva undulata (illustrated) and Sceloporus utiformis were the only two sampled species of lizards that were disturbance-sensitive. Both are terrestrial and forage in the leaf litter. Reduction of the litter may be responsible for the decline of these species in disturbed forests. R O B ER T PO W EL L Iguana 15.3 b&w text 9/10/08 5:44 AM Page 177 178 IGUANA • VOLUME 15, NUMBER 3 • SEPTEMBER 2008 CONSERVATION RESEARCH REPORTS influential factors. Carlyle Lake, a popu- lar tourism/recreation area, is situated in a larger agricultural landscape and is home to the largest Illinois population of the endangered Eastern Massasauga (Sistrurus catenatus). The authors docu- mented 321 cases of reptilian road mor- tality (84 individuals of six turtle species and 237 individuals of nine snake species) while driving the approx. 46-km study route roundtrip daily. Turtle road mortality was highest in May and June, and positively associated with precipita- tion and minimum daily temperature. Colubrid snake road mortality was high- est in April and October, and positively associated with minimum daily temper- ature. We recorded 42 cases of road mor- tality of S. catenatus, with the highest number occurring from mid-August to mid-September. Road mortality in S. catenatus was biased toward adult males, which show an increase in movement in August, coinciding with the peak of the mating season and a period of high tourist visitation. The traffic intensity on a road segment did not significantly affect the level of road mortality, but seg- ments through high-quality habitats had higher levels of mortality than segments through lower quality habitats. Refutation of Traditional Chinese Medicine Claims about Turtles The Chinese turtle trade is the primary threat to endangered turtle populations throughout Asia, primarily because of the long tradition of consuming turtles in China. Practitioners of Traditional Chinese Medicine (TCM) promote nutritional and medicinal benefits from eating turtles, especially hardshell species. MEILING ET AL. (2008. Applied Herpetology 5: 173–187) tested these claims by determining the nutritional value of turtle products (meat, fat and shell) in five species of geoemydid turtle, Cuora trifasciata, C. mouhotii, Mauremys mutica, M. sinensis, and Geoemyda speng- leri. The authors analyzed nutritional vari- ables such as the composition of amino acids, fatty acids, and mineral elements to determine the relative nutritional quality of turtle products. Their study refutes TCM claims about products made from hardshell turtles. Alternative animal prod- ucts should be substituted to obtain sim- ilar minerals, amino acids and fatty acids. Balancing the cultural use of turtles with their conservation status remains a major challenge. A Sixth Mass Extinction? Many scientists argue that we are either entering or in the midst of the sixth great mass extinction. Intense human pressure, both direct and indirect, is hav- ing profound effects on natural environ- ments. The amphibians — frogs, sala- manders, and caecilians — may be the only major group currently at risk glob- ally. A detailed worldwide assessment and subsequent updates show that one- third or more of the 6,300 species are threatened with extinction. This trend is likely to accelerate because most amphibians occur in the tropics and have small geographic ranges that make them susceptible to extinction. The increasing pressure from habitat destruc- tion and climate change is likely to have major impacts on narrowly adapted and distributed species. WAKE AND VREDENBURG (2008. Proceedings of the National Academy of Sciences 105: 11466–11473) showed that salamanders on tropical mountains are particularly at risk. A new and significant threat to amphibians is a virulent, emerging infec- tious disease, chytridiomycosis, which appears to be globally distributed, and its effects may be exacerbated by global warming. This disease, which is caused by a fungal pathogen and implicated in serious declines and extinctions of >200 species of amphibians, poses the greatest threat to biodiversity of any known dis- ease. The authors’ data for frogs in the Sierra Nevada of California show that the fungus is having a devastating impact on native species, already weak- ened by the effects of pollution and introduced predators. A general message from amphibians is that we may have lit- tle time to stave off a potential mass extinction. Road mortality of the endangered Eastern Massasauga (Sistrurus catenatus) was biased toward adult males, which show an increase in movement in August, coinciding with the peak of the mating season and a period of high tourist visitation. M IC H A EL R ED M ER D O N S H EP A R D Analysis of turtle meat from five species of Chinese turtles, including Cuora trifasciata, refuted claims about the nutritional value of eating hardshell turtles. TO R ST EN B LA N C K _W IK I.T IF Amphibian population declines, extirpa- tions, and extinctions may be the first sign of an impending mass extinction. The status of the critically endangered Mountain Yellow- legged Frog (Rana muscosa) may be a harbin- ger of other declines in the United States. JE FF L EM M Iguana 15.3 b&w text 9/10/08 5:44 AM Page 178