Southern right whales generally appear not to react to transiting research vessels

Abstract

Reactions of southern right whales (SRWs) related to whale-watching boats have been reported in Patagonia, but there are no quantitative data showing how these whales react to boats not preforming whale-watching trips. The objective of this study was to investigate the reaction of SRWs to transiting vessels. Data were collected off the coast of Puerto Madryn city, and were analyzed by means of cumulative logit models, using the whales' intensity of behavioral response as an ordinal dependent variable. During the experimental approaches of a research vessel, we found that the response of SRWs differed depending on the number of whales present. The results of this study show that the probability of response to transiting vessels is low, unless there are only a few whales in a group, or it is a mating group. This response is different from that of an approaching whale-watching vessel. In this study, the lack of reaction of whales to the research vessel suggests that whales would not consider it as a threat. This study represents an important piece of information for the conservation of southern right whales.