Animals are expected to perform certain behaviours, depending on their own and external situations. Disentangling their decision processes would help to predict why and when the animals take certain behavioural decisions. In this project, we focus on so-called crawling-out behaviour of the great pond snail, Lymnaea stagnalis. Previous studies showed that this freshwater snail species tends to crawl out of the water in response to the presence of mating partners, thereby prolonging and potentially avoiding unwanted inseminations (Moussaoui et al, 2018; Daupagne and Koene 2020). It has also been shown that such ‘terrestrial’ locomotion requires extra effort for the snails. These two pieces of information lead us to question whether the snails would still crawl out, when they have depleted their energy (i.e. performed a physically demanding task) prior to their mating. In this project, we aim to answer this question by quantifying mating behaviour and reproductive performance of L. stagnalis.


– Behavioural observation
– Quantifying reproductive outputs
– Statistical analyses


Animal behaviour, sexual selection, sexual conflict, energy budget, reproduction


Moussaoui, R., Verdel, K., Benbellil-Tafoughalt, S., & Koene, J. M. 2018. Female behaviour prior to additional sperm receipt in the hermaphroditic pond snail Lymnaea stagnalis. Invertebrate Reproduction and Development, 62(2), 82–91

Daupagne, L., & Koene, J. M. 2020. Disentangling female postmating responses induced by semen transfer components in a simultaneous hermaphrodite. Animal Behaviour, 166, 147–152.


Dr. Joris M. Koene

Dr. Yumi Nakadera