Abstract

Dice snakes (Natrix tessellata) can reach exceptionally large population densities where local conditions permit. Here we report on a study of one large population from Histria, the southern-most area of the Danube Delta in Romania. There the dice snakes forage in the brackish waters of Lake Sinoe. Many snakes are visibly infected by parasitic nematodes, which have piscivorous birds as definitive hosts. The nematode, Eustrongylides excisus, can be fatal to its snake host. In 2005, we began to study the dice snake population at Histria. In 2006 we initiated a monitoring study based on capture-mark-recapture methodology using PIT tag markers. This paper presents general aspects of this population and analyses the results to date in relation to fieldwork effort. We also discuss how external factors may affect the dynamics of the population. Even though it is generally considered that the population was larger in the past, we have not found evidence of a population decline. We estimate that the population has remained at or above 10,000 adult individuals during the three years of PIT tagging

Keywords

Population census; Natrix tessellata; size; PIT tag; Eustrongylides parasites

Published in

Mertensiella
2011, number: 18, pages: 237-244
Publisher: Deutsche Gesellschaft für Herpetologie und Terrarienkunde

SLU Authors

• Kärvemo, Simon

  • Department of Ecology, Swedish University of Agricultural Sciences
    

UKÄ Subject classification

Ecology


Permanent link to this page (URI)

https://res.slu.se/id/publ/34896