Raquel Rocha Santos

Directional orientation of migration in an aseasonal explosive-breeding toad from Brazil

The directional orientation of pre- and post-reproductive migration was studied in the Brazilian red-bellied toad Melanophryniscus cambaraensis, a species that forms explosive-breeding aggregations at irregular intervals throughout the entire year. Migrating toads were captured by enclosing the breeding site in dual drift fences with inward- and outward-facing funnel traps. Data were collected over 5 mo and totalled 333 captures. The observed directional orientation was significantly different from expected under a uniform distribution for both pre- and post- reproductive migration, regardless of gender. Males and females did not differ significantly from each other in the orientationofentryorexit,andthedirectionalorientationofpre-reproductivemigrationwasnotsignificantlydifferent from post-reproductive migration. It is suggested that the observed directional bias may be due to a dirt road next to the breeding site that could restrict juvenile dispersal to the adjacent forest.

Clip or Snap? An Evaluation of Toe-Clipping and Photo-Identification Methods for Identifying Individual Southern Red-Bellied Toads, Melanophryniscus cambaraensis

ABSTRACT. The most common method for identifying individual amphibians is toe-clipping (TC), whereby captured individuals are marked by a unique combination of amputated phalanges that corresponds to a unique alphanumeric code. However, ethical and methodological objections to this method have been raised and there is broad interest in developing alternative methods. One alternative is to use photo-identification methods (PIMs) to identify individuals based on their natural markings. We tested the efficacy of TC and two PIMs — visual matching (VM) and computer-assisted matching (CAM) using the software Wild-ID — in identifying individual adults of the endangered southern red-bellied toad, Melanophryniscus cambaraensis. We collected data over 5 mo at Floresta Nacional de São Francisco de Paula, Rio Grande do Sul, Brazil. All specimens were toe-clipped and photographed. The total dataset included 492 captures of 147 individuals. VM was most accurate (99.4%), followed by TC (95.3%) and CAM (90.9%); VM was significantly more accurate than TC and CAM and TC was significantly more accurate than CAM. CAM accuracy diminished as dataset size increased but was considerably faster than VM. All CAM and VM errors were false negatives but involved different images; all TC errors were cross-identifications. Given that misidentifications occurred using both PIMs and TC, our results suggest that studies that require high accuracy should employ at least two methods to allow cross-validation. The performance of each method and the impacts of different kinds and rates of error on inferences depend on the organisms, field conditions, dataset sizes, and study questions. As such, researchers must carefully evaluate the trade-offs of each method before investing significant time and resources in collecting field data.

Amphibia, Anura, Cycloramphidae, Proceratophrys bigibbosa (Peters, 1872) and Proceratophrys brauni Kwet and Faivovich, 2001: distribution extension and new state record

Proceratophrys Miranda-Ribeiro, 1920 includes 18 species of cycloramphids (Frost 2009) commonly known as the smooth horned frogs (Frank and Ramus 1995). As indicated by the group’s common name, the eyelids of many species are adorned with elongate dermal appendages (for review see Prado and Pombal 2008). Several other species of Proceratophrys lack conspicuous palpebral appendages, including the type species P. bigibbosa (Peters 1872) and P. brauni Kwet and Faivovich 2001. These species are included in the P. bigibbosa species group, which was characterized by Lynch (1971) as lacking hornlike palpebral appendages and having a short, blunt snout, postocular cranial protuberances, and large marginal tubercles on eyelids.