Phänologie, Bestandsentwicklung und Populationsstruktur eines isolierten Vorkommens des Teichmolchs Lissotriton vulgaris (L.) in der Stadt Halle (Saale)

Schatz, J., Petzold, A., Grosse, W.-R.: Phenology, demography and population structure of the Smooth newt, Lissotriton vulgaris (L.) in an isolated pond within the city of Halle (Saale). - Hercynia N. F. 45 (2012): 209 – 226. In the spring of the years 2009 to 2011 a population of the Smooth newt was examined in the east court of the zoological institute in the city Halle (Saale). Within a city population of the Smooth newt should be characterised for the first time concerning the phenology, sex ratio, age and biometrics. Within the scope of these investigations the following standard methods were used: net catch, mark / mark recapture methods, biometrics, photo documentation of belly patterns for individually identification and sceletochronology. The immigration of the newts into the spawning water varied considerably, limited by the regional weather conditions during the years of investigation. In all years, a later migration of the females than the males to the spawning waters could be observed. The annual recapturing rate varied between 70 - 87 % without sex-related differences. In 2009, the population size was about 104 ± 27.3 (86 individuals were captured). In 2010 to 2011, 34 ± 3.3 and 58 ± 7.7 animals were estimated (38 or rather 58 individuals were captured). In this regard the sex ratio was approximately 1:1. The average age ranged between 4 and 5 years, the age range was between 2 and 9 years. Regarding the head-body length and body mass, there were differences between the study years 2009 / 2010 and 2009 / 2011. The newts in 2009 were on average not only heavier but also larger than the animals examined in the following research years. The condition index increased during the study period. The head-body length varied considerably within each age group of newts. In comparison with populations in natural habitats, the animals of the city were smaller. An accurately age assignment on the basis of the head-body length was not possible. Overall, the three- (2009) and four-year old (2010) individuals dominated within the population. Key words: Amphibia, Smooth newt, urban population, phenology, population structure, morphometry.