Monitoring the behavior of freely moving lobsters with accelerometers

Accelerometers are useful devices for monitoring the activity of a variety of lobster species, both in the laboratory and the field. While the method has proven beneficial for determining when animals are active, it is more difficult to determine the actual distance animals travel or the intensity of their movements based on accelerometry. To achieve this goal, we monitored American lobsters, Homarus americanus H. Milne-Edwards, 1837, fitted with HOBO accelerometer dataloggers and Vemco V13AP accelerometer transmitters in the laboratory and simultaneously obtained time-lapse digital videos of their behavior. We used these data to convert accelerometer outputs to distances moved per unit time. The outputs of both types of accelerometers were well correlated with distance traveled. We then used this information to analyze data obtained in a previous study, using the same HOBO accelerometers. This made it possible to calculate to what extent activity and the distance traveled per hour changed on a seasonal basis over a year. This analysis also revealed that lobster activity in the field was significantly greater than activity in the lab at the same time of year, within similar enclosures. Overall, these results demonstrate that accelerometry is a suitable and accurate method for monitoring the relative activity of lobsters over long periods in the laboratory and field and the results compare favorably with other published studies of lobster movements.