Interaction between juvenile narrow-claw crayfish, Astacus leptodactylus (Eschscholtz), and common water frog, Rana esculenta (L.), tadpoles or common blue damselfly, Enallagma cyathigerum (Charpentier), larvae during rearing under controlled conditions

Abstract

Interaction between juvenile narrow-claw crayfish, Astacus leptodactylus (Eschscholtz), and common water frog, Rana esculenta (L.), tadpoles or common blue damselfly, Enallagma cyathigerum (Charpentier), larvae during rearing under controlled conditions Dariusz Ulikowski, Iwona Piotrowska, £ucjan Chybowski, Tadeusz Krzywosz, Piotr Traczuk Received -07 July 2014/Accepted -06 October 2014. Published online: 31 December 2014 ©Inland Fisheries Institute in Olsztyn, Poland Citation: Ulikowski D., Piotrowska I., Chybowski £., Krzywosz T., Traczuk P. 2014 -Interaction between juvenile narrow-claw crayfish, Astacus leptodactylus (Eschscholtz), and common water frog, Rana esculenta (L.), tadpoles or common blue damselfly, Enallagma cyathigerum (Charpentier), larvae during rearing under controlled conditions -Arch. Pol. Fish. 22: 257-264.Abstract. Interactions were studied among juvenile narrow-claw crayfish, Astacus leptodactylus (Eschscholtz), and common water frog, Rana esculenta (L.), tadpoles and common blue damselfly, Enallagma cyathigerum (Charpentier), larvae during rearing under controlled conditions. Interactions among the species studied had a positive impact on the survival of the crayfish, but the differences were not statistically significant (P ³ 0.5). The juvenile crayfish attacked and consumed the frog tadpoles and damselflies, but the juvenile crayfish very rarely fell prey to them. Only in the initial stage of life and during molting did larval damselflies prey upon juvenile crayfish. After 30 days of the experiment the interaction between crayfish-tadpoles and crayfish-larval damselflies was not noted to have had a statistically significant (P ³ 0.05) impact on crayfish growth. Juvenile crayfish aggression toward tadpoles and larval damselflies was often offset by the loss of even both chelipeds. In the crayfish-larval damselfly interaction the loss of both chelipeds was three-fold more common than it was in the crayfish-tadpole interaction; however, these differences were not statistically significant (P ³ 0.5). The effect of intraspecific interaction (crayfish-crayfish) was more a threat in terms of mortality from cannibalism than were interspecific interactions (crayfish-tadpole and crayfish-larval damselfly).

Predation impact of common backswimmer (Notonecta glaucaL.) on juvenile narrow-clawed crayfish (Astacus leptodactylusEsch.)

“…In our study, the survival of juvenile A. leptodactylus was highest in the group where the crayfish were kept separately in individual compartments. This is another confirmation of previous results that this is the only way to completely eliminate crayfish cannibalism (Ulikowski et al., ). Cannibalism is one of the main reasons for the decline in survival of juvenile A. leptodactylus during their rearing, and survival decreases with increasing holding density (Ulikowski & Krzywosz, ).…”

“…The results of our study showed that the presence of N. glauca caused a reduction in activity of juvenile A. leptodactylus . A similar effect was observed in the case of the impact of predatory fish on crayfish (Appelberg, Söderbäck & Odelström, ), as well as in case of the impact of dragonfly larvae or frog tadpoles on juvenile crayfish (Ulikowski et al., ). By changing their behaviour, crayfish can survive in environments with a high density of potential predators.…”

“…In this study, the effect of predation of N. glauca on juvenile A. leptodactylus , apart from the decrease in survival and mortality, is also demonstrated in the higher proportion of individuals completely devoured. Interestingly, even in the presence of non‐predatory organisms in tanks, an increase in survival of juvenile A. leptocactylus was obtained (Ulikowski et al., ). Probably, the presence of potentially dangerous alien organisms also decreases juvenile crayfish activity.…”

“…According to Stein and Magnuson () crayfish try to avoid direct contact with predatory insects, or use their chelipeds to defend themselves. Juvenile crayfish are more likely to lose both chelipeds in interaction with other organisms than in intra‐species interactions (Ulikowski et al., ). According to Hirvonen (), cheliped autotomy is an effective method of defence of juvenile P. leniusculus before being eaten by predatory N. lutea .…”

“…The period when juvenile crayfish begin an independent existence after leaving their mothers is the most dangerous in their life. Their relatively small size causes them to be exposed to many different potential predators, such as fish, insects and their larvae, bugs and amphibians (Gydemo, Westin & Nissling, ; Hager, ; Jonsson, ; Munkhammar, Gydemo, Westin & Ackefors, ; Ulikowski, Piotrowska, Chybowski & Traczuk, ). One of the most common and aggressive predators are insects of the genus Notonecta, and they are also very prone to cannibalism (Papáček, ).…”