Dramatic decline and range contraction of the Endangered Patagonian frog Atelognathus patagonicus (Anura, Leptodactylidae)

Abstract

The Endangered frog Atelognathus patagonicus is endemic to the Laguna Blanca wetland system, Patagonia, Argentina. This species has undergone a significant contraction of its original distribution, including loss of the main population from the largest lagoon, Blanca. The decline of A. patagonicus was first perceived in 1986 and was thought to be at least partially associated with the anthropogenic introduction of the perch Percichthys colhuapiensis for sport. To evaluate the potential impact of P. colhuapiensis on A. patagonicus we surveyed for both species in 28 lagoons, and found A. patagonicus present in 23. These lagoons represent, however, only a small percentage of the total wetland area. The presence of A. patagonicus was associated with lagoons characterized by absence of P. colhuapiensis and high abundance of macrophytes. The most severe problem facing the remaining populations is in the many lagoons currently not protected by Laguna Blanca National Park. Conservation efforts need to focus on the prevention of fish introductions in the wetlands areas on private land. A project to restore A. patagonicus to Laguna Blanca, and educational programmes emphasizing the protection of Patagonian wetlands as reservoirs of regional biodiversity, are currently under development.

Invasion Complexities: The Diverse Impacts of Nonnative Species on Amphibians

“…Invasion complexity in amphibian systems promoted by indirect and direct ecological effects of introduced fishes.-One of the greatest threats to native amphibians continues to be introduced fishes (Denoël and Ficetola, 2008;Cuello et al, 2009;Gall and Mathis, 2010;Hunter et al, 2011;Reshetnikov and Ficetola, 2011). Fish introductions can be accidental or intentional when released for game fishing (e.g., Welsh et al, 2006;Barrionuevo and Ponssa, 2008) or as pest control agents (Leu et al, 2009;Segev et al, 2009).…”

Atividade trófica sazonal do morfótipo aquático de Atelognathus patagonicus (Anura, Neobatrachia) e disponibilidade de presas no bentos litorâneo de uma lagoa permanente da Patagônia Argentina

“…Overwintering Atelognathus patagonicus tadpoles have been reported by Cuello and Perotti (2006) as a result of observations at Laguna Verde from June to August 2004 (austral winter), under the harshest winter climatic conditions. Our study found that in the 1.2 -4.4 °C interval, adult A. patagonicus specimens overwinter submerged in the rocky littoral maintaining their mobility, as noted by their entering into the funnel traps.…”

Plastic patterns in larval development of Endangered endemic Atelognathus patagonicus: implications for conservation strategies

“…Previous studies have reported that most ponds inhabited by Atelognathus patagonicus are permanent (Fox et al 2005, Cuello et al 2009a). Since overwintering only occurs in permanent ponds, it may be said to prevail as a development strategy in this anuran species, at least for the period during which the studies were performed.…”

“…The endemic frog Atelognathus patagonicus (Gallardo, 1962) lives in permanent and temporary water bodies in a system of fish-free endorheic ponds on the basaltic plateau in Laguna Blanca National Park and surroundings in north-western Argentinean Patagonia (Cuello et al 2009a). The distribution of A. patagonicus is restricted to one of the harshest habitats of the Patagonian steppe, with long winters during which the surface of water bodies remains frozen and covered in snow for several months of the year (June to August).…”