The macrophyte, Stratiotes aloides, protects larvae of dragonfly Aeshna viridis against fish predation

• Published in: Aquatic ecology Vol. 38; no. 1; pp. 77 - 82
• Main Authors: J. Rantala, Markus, Ilmonen, Jari, Koskimäki, Jani, Suhonen, Jukka, Tynkkynen, Katja
• Format: Journal Article
• Language: English
• Published: Dordrecht Springer Nature B.V 01-01-2004
• Subjects: Aeshna viridis; Aquatic insects; Aquatic plants; Endangered & extinct species; Endangered species; Freshwater; Larvae; Myriophyllum alterniflorum; Odonata; Perca fluviatilis; Stratiotes aloides; Finland, South
• ISSN: 1386-2588; 1573-5125
• DOI: 10.1023/B:AECO.0000021005.22624.16

Predation could be one force determining which contemporary species occupy a certain habitat. Aeshna viridis is an endangered dragonfly species with a larval distribution strongly associated with lakes where the water plant, water soldier, Stratiotes aloides, occurs. In this study, the larvae were almost exclusively found in patches of S. aloides. To study larval association with S. aloides further, we conducted a series of laboratory experiments. Behavioural experiments indicated that larvae preferred S. aloides. Aeshna viridis larvae were nocturnal and rather inactive. Larvae on S. aloides were less susceptible to predation by the perch, Perca fluviatilis, than larvae on another water plant, Myriophyllum alterniflorum. According to our study it seems that occurrence of S. aloides may limit the distribution of A. viridis, and the protection of refuges may be essential in planning the conservation of this endangered species.