Experimental Evidence for Homing in the Red Swamp Crayfish, Procambarus Clarkii

Abstract

The red swamp crayfish, Procambarus clarkii, is an efficient burrower, but its burrow fidelity has been recently questioned. In this study, we aimed at investigating whether individuals of this species are capable to learn the position of a goal (a wet burrow hidden to their sight) in experimental tanks and to make more efficient with time their oriented movement towards it. We also analyzed crayfish behavior after having closed one of the two accesses to the goal. Indeed, in successive trials we recorded the crayfish tendency to reduce the distance covered to reach the goal and the time taken, except when they were already familiar to the experimental setting. Memory of the spatial configuration lasted for 16 hours at least and crayfish learned and maintained individual trajectories. The interruption of their usual path always caused a drastic increase of distance and time that however decreased in the successive trials. This study provided also some information of the sensory channels used by P. clarkii to orient. This crayfish, which can be active also during daytime, seemed to adopt a combination of tactile and visual information, together with the possible use of cues (i.e. humidity cues) emitted by the goal. Future studies should clarify the paradox of a crayfish species whose individuals, although being physiologically capable to home, seem not to return to the previously occupied burrows at the end of their foraging excursions, notwithstanding the time and energy expended to excavate them.Key-words: spatial learning, red swamp crayfish, Procambarus clarkii. PREUVE EXPÉRIMENTALE DU HOMING CHEZ L'ÉCREVISSE DE LOUISIANE, PROCAMBARUS CLARKII RÉSUMÉL'écrevisse rouge de Louisiane, Procambarus clarkii, est un fouisseur efficace, mais sa fidélité au terrier a été récemment mise en doute. Lors de cette étude, nous avons étudié la capacité des individus de cette espèce à mémoriser la position d'un but (un terrier humide caché à leur vue) dans des réservoirs expérimentaux et à optimiser leurs déplacements. Nous avons également analysé le comportement de l'écrevisse après avoir clos un des deux accès au but. En effet, dans des épreuves successives nous avons Bull. Fr. Pêche Piscic. (2006) 380-381 : 1145-1154 -1146 -constaté la tendance de l'écrevisse à réduire la distance couverte pour atteindre le but, et la durée du déplacement, sauf lorsqu'ils étaient déjà familiarisés avec l'arrangement expérimental. La mémoire de la configuration spatiale a duré au moins pendant 16 heures et l'écrevisse a appris et maintenu une trajectoire individuelle. L'interruption de leur chemin habituel a toujours causé une augmentation énergique de la distance et de la durée du trajet, qui a cependant diminué lors des tentatives successives. Cette étude a fourni également quelques informations des canaux sensoriels employés par P. clarkii pour s'orienter. L'écrevisse, qui peut être en activité également pendant la journée, a semblé adopter une combinaison d'informations tactiles et visuelles, ainsi que l'utilisation possible des ...

Genetic diversity and population structure of the invasive alien red swamp crayfish

“…Whether epigenetic adaptation played a role in the successful invasion of P. clarkii remains to be examined. Studies of the biology of P. clarkii have revealed a number of traits that make this crayfish a successful invader (Barbaresi et al 2003;Barbaresi and Gherardi 2006;Gutierrez-Yurrita and Montes 1999) including early maturity at small body size, rapid growth rates, large numbers of offspring at a given parental size, relatively short life spans, tolerance to environmental extremes and a wide behavioral flexibility when coping with new types of predators. These traits are likely to be determined by a number of genes with small effects and environment influences, and can not be analyzed directly with natural DNA markers.…”

Red swamp crayfish: biology, ecology and invasion - an overview

“…humidity cues) to orientate its burrowing behaviour; burrows are used as refuge to avoid predation, dehydration and environmental stress as well as to nest (Huner and Barr, 1991;Barbaresi and Gherardi, 2006). However, despite the great importance of these shelters, individuals seem not to return to previously occupied burrows at the end of their foraging excursions despite the time and energy expended to excavate them (Barbaresi and Gherardi, 2006). This species, like most freshwater crayfishes, shows relatively complex parental care 1997;Vogt and Tolley, 2004).…”

Spatial dynamics of the noble crayfish (Astacus astacus, L.) in the Paklenica National Park

“…The literature provides a few reports on the spatiotemporal activity of the native European species, such as the white-clawed crayfish (Gherardi et al, 1998;Acquistapace and Gherardi, 1999;Barbaresi et al, 1999). In recent years, a significant amount of research has been conducted in relation to movement patterns of invasive crayfish species in Europe 2002;Barbaresi et al, 2004;Aquiloni et al, 2005;Barbaresi and Gherardi, 2006;Bubb et al, 2004;2006a) and differences in spatial behaviour between invasive and native species (Bubb et al, 2006b). Only a few authors have described movement patterns of small samples of Astacus astacus in natural habitats (Bohl, 1999;Schütze et al, 1999), using radio telemetry.…”