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

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 offshore 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 during 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 warrant an evaluation of current management protocols in order to provide adequate protection to the population in the face of offshore energy development activities.

North Atlantic right whale Eubalaena glacialis occurrence in offshore wind energy areas near Massachusetts and Rhode Island, USA

“…In this study, concurrent acoustic monitoring by the Cornell University Lab of Ornithology revealed a longer period of occurrence than the shorter seasonal period that was detected by aerial surveys . Re cent studies of E. glacialis distribution in coastal areas that used a combination of acoustic and visual assessment techniques found that aerial surveys were useful for estimating abundance and identifying individuals, but that acoustic monitoring detected occurrence over longer periods of time (Whitt et al 2013, Hodge et al 2015, Oedekoven et al 2015.…”

Phenological changes in North Atlantic right whale habitat use in Massachusetts Bay

“…Potential up‐calls that were repeated at regular intervals or that were closely associated with other frequency‐modulated sounds likely to be from humpbacks were considered to be humpbacks or of ambiguous species identity and were eliminated. This conservative approach to discriminating between right whale up‐calls and humpback sounds is similar to that used in other studies (Hodge et al, ; Mellinger et al, ; Mussoline et al, ; Salisbury et al, ). Detected sounds within each hour were examined only until one confirmed up‐call was found.…”

“…This is the first study to quantify interannual variation in right whale year‐round use of a specific area over more than 3.5 years. Earlier PAM studies have provided important insights into right whale presence at places or times of year where they had previously not been observed in modern times (Bort et al, ; Hodge et al, ; Mellinger et al, ; Morano et al, ; Mussoline et al, ; Salisbury et al, ; Whitt et al, ). However, with the exception of the study by Morano et al (; see below), which used a subset of the data reported here, those studies were limited to 1 or (in one case: Whitt et al, ) 2 years at any given site, providing useful but limited snapshots of habitat use.…”

“…In the one study directly comparing PAM and aerial surveys, PAM was more reliable for detecting right whale presence in CCB, particularly at low whale densities (Clark, Brown, & Corkeron, ). Previous fixed‐location PAM studies have revealed the presence of right whales at times of year and/or places previously undocumented by recent visual observations (Bort, Parijs, Stevick, Summers, & Todd, ; Hodge, Muirhead, Morano, Clark, & Rice, ; Mellinger, Nieukirk, et al, ; Morano et al, ; Muirhead et al, ; Mussoline et al, ; Salisbury, Clark, & Rice, ; Whitt, Dudzinski, & Laliberté, ). These studies, most of which were limited to 1 or 2 years, have demonstrated the value of PAM methods for filling in important gaps in our understanding of right whale occurrence patterns in space and time.…”

Right whale occurrence in the coastal waters of Virginia, U.S.A.: Endangered species presence in a rapidly developing energy market

“…, Hodge et al . ), putative up‐calls in the presence of additional frequency‐modulated sounds reoccurring often within 3–5 s were discarded as most likely being a humpback whale, whereas individual up‐calls with longer intercall intervals were considered to be from right whales. We estimated that contact calls could be detected on the MARUs at a range of approximately 10–20 km (Clark et al .…”