Abundant prey or optimal microhabitat? Natrix tessellata stays hidden in safe areas in a diverse floodplain along the Danube at God, Hungary

作者：Gaebele Tibor; Potyo Imre; Weiperth Andras; Guti Gabor; Puky Miklos^*

来源：North-Western Journal of Zoology, 2013, 9(2): 374-382.

• Natrix tessellate
• Reptilia
• juvenile fish
• environmental parameters
• habitat preferences
• Middle-Danube

Natrix tessellata (Laurenti, 1768) is a diurnal piscivorous Eurasian snake species with a large distribution area. Along the River Danube it is present in the floodplain and along the lower stretch of tributaries. The distribution of N. tessellate among the different microhabitats along the River Danube at God (1669-1671 rkm) and its relationship with environmental parameters and fish presence/absence, species composition, size distribution and abundance was studied at eight selected sections. Samples were collected twice a month from March to October in 2008-2009; N. tessellata was found between May and early October. Altogether 26 N. tessellata sightings were recorded together with 497 individuals of 21 fish species along the same sections, while another 5,547 individuals belonging to 28 fish species were caught in snake-free areas. Microhabitat characteristics were more important than the presence of fish in determining along which section N. tessellate stays. It favoured slow-flowing sections with aquatic macrophytes and a sandy or muddy bottom. In spite of their suitability, artificial habitats were not much used maybe due to increased risk of disturbance and predation/persecution. The habitat preference of N. tessellata changed less between the two studied years with different water level fluctuations than those of fishes and it was not identical with that of any of the fish species caught. However, fish 15-30 mm and longer may influence the distribution of N. tessellata.

• 出版日期2013-12