Changes in female reproduction and body condition in an endemic lizard, Phymaturus spectabilis, following the Puyehue volcanic ashfall event? Herpetological Conservation and Biology

BORETTO, JORGELINA; CABEZAS-CARTES, FACUNDO; KUBISCH, ERIKA; SINERVO, BARRY; IBARGÜENGOYTÍA, NORA

Herpetological Conservation and Biology

Malcolm L. McCallum

Año: 2014 vol. 9 p. 181 - 191

1931-7603

Puyehue is a largely basaltic stratovolcano located in the southern volcanic zone of the Andes, with an irregular inter-occurrence intervals of eruption which affects the ecology of the native communities. The lastest Puyehue eruption occurred in June 2011and dispersed about 100 million tons of pyroclastic materials to the Patagonia steppe of Argentina, due to the West?East predominant winds, affecting an area of over 7.5 million hectares. The deposition and accumulation of large amounts of volcanic ashes reduced the availability of forage and affected the health of sheep. Herein we report the consequences of volcanic ash accumulation in Argentinian Patagonian steppe, on the reproductive cycle of females and body mass of adult males, females, juveniles, and newborns of Phymaturus spectabilis, a lizard with a vulnerable conservation status. This species is a microendemic on specific volcanic rocky outcrops, in cold and arid environments of Ingeniero Jacobacci, Río Negro, Argentina. We studied the reproductive female cycle during the first (years 2011-2012) and the second activity season post-eruption (years 2012-2013), and discussed the results in relation to the reproductive cycle studied before volcano eruption (years 2006-2011). We found that only 12% of adult females captured were reproductive during the first activity season, which indicates that most P. spectabilis, skipped reproduction the year of volcano eruption. In contrast, during the second activity season post-eruption 83% of adult females were reproductive, although clutch size was changed to one to three offspring, instead of the fixed two offspring reported for P. spectabilis before the volcanic eruption, which is also characteristic of the Phymaturus genus. In addition the body mass of offspring born on 2013 was significantly lower than the body mass of offspring born before the volcanic eruption. Present results highlights the detrimental effects of ash fall on the reproduction and the body mass of a population of a lizard P. spectabilis during the first activity season, but the rapid recovery of the population during the second activity season post-eruption, indicative of heretofore unobserved plasticity in litter size.