Interpopulation variation in predator avoidance behavior of a freshwater snail to the same predator

Abstract

The New Zealand mud snail (Potamopyrgus antipodarum (J.E. Grey, 1843)) responds to the presence of predatory fish by moving to a safer environment. These experiments attempted to determine if predator detection by the snail results in specific responses to light and (or) gravity by the snail and if snails respond more or less to fish from their native lake compared with fish from a foreign lake. Snails and fish (Gobiomorphus cotidianus McDowall, 1975) were collected from lakes Alexandrina and Peorua from the South Island of New Zealand. Snails were placed in behavioral chambers and tested for their responses to the direction of light, vertical orientation with respect to gravity, and rate of movement in light and dark conditions. Snails from each lake were exposed to one of three treatments: plain water, water from fish from Lake Alexandrina, and water from fish from Lake Peorua. Results showed no effect of direction of light on behavior. Snails from Lake Alexandrina were not found to alter their up or down movements in response to the detection of fish. However, snails from Lake Peorua moved down more in response to fish from their own lake than fish from Lake Alexandrina or no fish. Both snail populations increase their speed in the light more when detecting Alexandrina fish compared with Peorua fish and no fish. Both snail populations show some evidence of enhanced response to local predator populations. Interestingly, different behavioral mechanisms appear to be responsible for the avoidance behaviors in each population.Résumé : La nasse de Nouvelle-Zélande (Potamopyrgus antipodarum (J.E. Grey, 1843)) réagit à la présence de poissons prédateurs en se dirigeant vers un milieu plus sûr. Les expériences menées tentaient de déterminer si la détection de préda-teurs par la nasse provoque des réactions particulières à la lumière ou à la gravité chez l'animal et si ce dernier réagit dans une plus ou moins grande mesure selon que le prédateur est issu de son lac natif ou d'un autre lac. Des nasses et poissons (Gobiomorphus cotidianus McDowall, 1975) ont été prélevés des lacs Alexandrina et Peorua, dans l'île du Sud de la Nouvelle-Zélande. Les nasses ont été placées dans des cages de comportement et ont fait l'objet de tests visant à déterminer leurs réactions à la direction de la lumière, à l'orientation verticale par rapport à la gravité et à la vitesse du mouvement dans des conditions d'éclairement et d'obscurité. Des nasses de chacun des deux lacs ont été exposées à l'un des trois traitements suivants : de l'eau ordinaire, de l'eau des poissons du lac Alexandrina et de l'eau des poissons du lac Peorua. Les ré-sultats ne révèlent aucun effet de la direction de la lumière sur le comportement. Aucune modification des déplacements vers le haut ou vers le bas en réponse à la détection des poissons n'a été observée chez les nasses du lac Alexandrina. Cependant, les nasses du lac Peorua se déplaçaient davantage vers le bas en réponse à la présence de poissons de leur propre lac qu'à celle de poissons du lac Alexandrina ...

Sex and Population Drive Interindividual Variations in a Cognitive Task Across Three Populations of Wild Zebrafish

“…Studies on a neotropical rainforest bird (Pyriglena leucoptera), showed that birds from populations found in highly fragmented habitats were better able to disperse than birds from intact habitats (Cornelius et al, 2017). Studies on snails, garter snakes and mayflies have shown that populations vary in the way they respond to the same predator (Arnold, 1992;McIntosh and Townsend, 1994;Levri et al, 2012).…”

Phenotypic Plasticity of the Introduced New Zealand Mud Snail, Potamopyrgus antipodarum, Compared to Sympatric Native Snails

“…Phenotypic plasticity may play a role in the environments where P. antipodarum is invasive. The snail is known to behave differently in the presence and absence of fish predators [7] and snails from different populations respond to fish predators differently [8] . Significant variation also exists between invasive and native clones in their growth rates at various salinities with invasive clones maintaining greater fitness at higher salinities [9] .…”