Predator detection inLymnaea stagnalis

Abstract

SUMMARY Laboratory-reared Lymnaea are capable of detecting and responding to the scent of a crayfish predator. The present investigation is a first attempt to characterize multiple stress-related behavioural responses resulting from predator detection and to depict the neurophysiological correlates of one of these illustrated behaviours. Snails respond to crayfish effluent (CE) by increasing the following behaviours: aerial respiration,exploratory/searching phase and sensitivity to the shadow-elicited full-body withdrawal response. In contrast, when snails detect CE they decrease both their righting response time when dislodged from the substratum and their basal cutaneous oxygen consumption. Interestingly, basal heart rate does not change in response to CE exposure. Finally, we directly measured the activity of the neuron that initiates aerial respiratory behaviour, RPeD1, in semi-intact preparations. Naïve snails exposed to CE prior to recording demonstrated both a significantly reduced spontaneous firing rate and fewer bouts of bursting activity compared with non-exposed snails. These data show that laboratory-reared Lymnaea that have never experienced a natural predator are still capable of detecting and responding to the presence of a historically sympatric predator. These data open a new avenue of research,which may allow a direct investigation from the behavioural to the neuronal level as to how an ecologically relevant stressful stimulus alters behaviour.

Fear is the mother of invention: anuran embryos exposed to predator cues alter life-history traits, post-hatching behaviour, and neuronal activity patterns

“…A link between neurophysiological changes and the parallel behavioural effects induced by predator cue detection was demonstrated in molluscs (Lymnea stagnalis; Orr et al, 2007;Lukowiak et al, 2008); in this case, however, an increase of breathing and overall defensive behaviour was associated with a decrease in firing and bursting activity of a key neuron in mediating both vigilance behaviours and memory formation. In crustaceans (e.g.…”

“…It is well known that developing embryos and tadpoles modify the timing of hatching/ metamorphosis as well as morphology and behaviour in response to the perception of chemical cues of predation (Van Buskirk, 2001;Laurila et al, 2002;Orizaola and Braña, 2004;Ireland et al, 2007;Ferrari and Chivers, 2009;, and this plasticity may result in increased survival (Mathis et al, 2008). In contrast, the neurophysiological changes underlying phenotypic behavioural plasticity induced by predator cues remain largely unexplored (Orr et al, 2007;Whitaker et al, 2011). Predator odours processed through the olfactory neural system may, for example, modulate the hypothalamo-pituitary-adrenocortical axis and hence corticosteroid production, which in turn mediates life-history, morphological and behavioural changes in tadpoles (Denver, 2009;Maher et al, 2013).…”

Behavioural evidence for a sleep-like quiescent state in a pulmonate mollusc, Lymnaea stagnalis (Linnaeus)

“…A milder stimulus of intermittent agitation using bursts of bubbles was found to be ineffective in preventing quiescence. Finally, placing the animals in an aquarium containing water obtained from a tank housing crayfish, a natural predator of Lymnaea (Orr et al, 2007), caused an increased incidence of apparent torpor, often in association with crawling clear of the water. Hence, this study remains inconclusive regarding whether Lymnaea possess a typical homeostatic response and resolution of this issue must await the development of a benign stimulus that effectively prevents quiescence for at least several days.…”

Individual boldness is linked to protective shell shape in aquatic snails

“…Each snail was allowed to retract into its shell, its own refuge, in response to a fright stimulus [17,18]. The assay was repeated after one week (see electronic supplementary material for more detail).…”