Meeting Abstract

P1.6  Wednesday, Jan. 4  The Effect of Experience on Shelter-Seeking Behavior of Early Juvenile Homarus americanus BIANCHI, K.M.*; JACOBS, M.W.; ATEMA, J.; BAYER, S.; Falmouth Academy; McDaniel College; Boston University; Darling Marine Laboratories

Previous research shows that juvenile lobsters (Homarus americanus) are strongly dependent on shelter, and avoid predator odor. There is additional evidence that year-old juveniles find shelter faster with experience. We hypothesized that very young (week-old) juveniles H. americanus would settle in shelter as quickly as possible, and would find the shelter faster with experience. We also hypothesized that predator odor (juvenile dogfish Mustelus canis) would decrease time to locate or relocate the shelter. We constructed a simple maze with a rock shelter at one end of the tank, with flow towards the shelter. Naïve lobsters were released into the maze and allowed to find the shelter, then removed and immediately re-released. Juveniles found the shelter significantly faster during the second trial. This result suggests that the lobsters learned the location of the shelter. We characterized flow in the chamber using a dye test and found evidence of a countercurrent, suggesting that the lobsters could have used olfactory cues to relocate the shelter. Once the lobsters made visual contact with the shelter, there was no difference between trials in the time it took to reach the shelter. Overall, the lobsters often found the shelter but then chose to leave, or occasionally found the shelter during the 1st trial but did not return to it during the 2nd trial, suggesting that juveniles may be more exploratory than previous literature suggested. Juvenile lobsters H. americanus show the ability to learn the location of shelter even at a very young age, and visual or olfactory cues may be involved.