North Atlantic right whale occurrence near wind energy areas along the mid-Atlantic US coast: implications for management

Kb Hodge,Cw Clark,Ca Muirhead,Jl Morano,An Rice

doi:10.3354/esr00683

Abstract

The distribution and seasonal patterns of the North Atlantic right whale, Eubalaena glacialis, inform management decisions that mitigate anthropogenic threats. Based on data from visual surveys, much of the population migrates between winter calving grounds in coastal waters adjacent to the southeast USA and summer feeding and nursery grounds adjacent to the northeast USA. However, little is known about right whale occurrence along the mid-Atlantic US migratory corridor. A better understanding of right whale occurrence in this region is needed prior to off- shore wind energy development activities, which may increase mortality risks and chronic impacts on the population. We conducted an 11 mo passive acoustic survey along coastal North Carolina and Georgia near several wind energy areas to document the acoustic occurrence of right whales in the southern region of the mid-Atlantic US coast. Right whales were acoustically detected across all seasons, with peak seasonal presence occurring during autumn in the Georgia site and during winter in the North Carolina site. A secondary peak in presence also occurred dur- ing June and July in the Georgia site, when right whales were not expected to be in the area. Given the nearly year-round presence of right whales in the survey areas, these results may war- rant an evaluation of current management protocols in order to provide adequate protection to the population in the face of offshore energy development activities.

Highlights

The North Atlantic right whale, Eubalaena glacialis, is one of the most endangered whale species in the world and is protected by the Endangered Species Act and the Marine Mammal Protection Act (Clapham et al 1999, Waring et al 2013)
There was no significant difference in detector performance between the North Carolina site and the Georgia site (Kruskal-Wallis, S = 382, Z = −0.97841, p = 0.3279)
Right whale up-calls were found in a majority of the months sampled during this study; since right whale up-calls typically have short, environmentally dependent propagation distances (Laurinolli et al 2003), our data suggest right whales are likely present in the surveyed sites throughout the year

Summary

INTRODUCTION

The North Atlantic right whale, Eubalaena glacialis, is one of the most endangered whale species in the world and is protected by the Endangered Species Act and the Marine Mammal Protection Act (Clapham et al 1999, Waring et al 2013). Based on data from visual surveys, right whale seasonal movements are characterized by a round-trip migration in nearshore waters along the western North Atlantic (Winn et al 1986) During their migration cycle, right whales aggregate in Florida and Georgia calving grounds during winter; migrate through mid-Atlantic coastal waters during late winter and early spring; enter northern feeding grounds in Cape Cod Bay, Massachusetts Bay, and the Great South Channel during spring; aggregate in the Bay of Fundy and Scotian Shelf feeding grounds during summer and early autumn; and return south during the winter (Kraus et al 1986, Winn et al 1986, Kenney et al 1995, 2001). We summarize the spatial and temporal patterns of right whale occurrence in the mid-Atlantic US migratory corridor, and we discuss the management implications of our findings with respect to mitigating threats introduced by offshore energy development

MATERIALS AND METHODS

RESULTS

DISCUSSION