A Whale of a Season! 102 Individual Right Whales Documented

Guest Blog by: New England Aquarium Aerial Survey Team: Sharon Hsu (Research Technician), Katherine McKenna (Assistant Scientist), and Orla O’Brien (Associate Scientist)

About Our Survey

The New England Aquarium has been conducting aerial surveys of the waters south of Martha’s Vineyard and Nantucket since 2011. The Aquarium’s survey area includes the Southern New England Wind Energy Areas and surrounding waters such as the Nantucket Shoals. These surveys to gather information on the large pelagic species (primarily whales, dolphins, and turtles) that use this area has been funded by the National Oceanic and Atmospheric Administration (NOAA), the Bureau of Ocean Energy Management (BOEM), and the Massachusetts Clean Energy Center's (MassCEC) Offshore Energy Program.

Over the past decade, we have collected important information on the abundance and seasonal patterns of marine animals – especially the critically endangered North Atlantic right whale (Eubalaena glacialis). Our data has been used to better plan the timeline for turbine installation in order to decrease any overlap with right whales and construction. However, we also collect data on right whale individual identities, behavior, and movements during the course of our surveys. From January to April 2023, we have flown eleven surveys and documented at least 102 individual whales – which is almost 1/3 of the entire population! 

New England Aquarium aerial survey team
New England Aquarium aerial survey team. From left to right: Sharon Hsu, Orla O’Brien, Katherine McKenna

Where are the whales?

Map of right whale sightings
Map showing right whale sightings from January to April 2023.

Nantucket Shoals is an important habitat for right whales, especially during the winter months. This past winter (January and February), all of our right whale sightings occurred in this shallow area. Many of these whales were concentrated in aggregations and would surface quickly between frequent dives, indicating they were feeding below the surface. This feeding aggregation stayed on the Shoals through March. 

Right whales coordinated feeding south of Martha’s Vineyard.
Right whales Herb (Catalog #1250) and Catalog #2920 coordinated feeding south of Martha’s Vineyard.

In mid-March, we started observing right whales south of Muskeget Channel, which runs between Martha’s Vineyard and Nantucket. During this time, there were still right whales on Nantucket Shoals, and we observed right whales feeding and socializing in both of these areas.  

What are the whales doing?

Bocce (Catalog #3860), belly up in the bottom center of the group, sighted in a SAG on February 12, 2023.
Bocce (Catalog #3860), belly up in the bottom center of the group, sighted in a SAG on February 12, 2023.

Although we think the whales primarily come to Southern New England to feed, we often see social behaviors like surface active groups (SAGs) as well. SAGs consist of two or more whales closely interacting at the surface; SAGs can (but do not always) involve mating behaviors. Often there is a single “focal” animal at the center of a SAG that floats belly up at the surface while the other whales dive and roll around it. One of our largest SAGs this year was a group of eight whales with an adult female, Bocce (Catalog #3860), as the focal animal. Bocce is 15 years old and has already had two calves: one in 2016 and one in 2021. Bocce’s status as a calving female makes her critically important to the recovery of this species. 

Right whales in a surface active group (SAG)
Right whales in a surface active group (SAG) on March 10, 2023.

What changes have we noticed this year?

In April, right whale sightings often trail off in our study area as the whales move onto other habitats. However, in April 2023, we documented a small group of right whales in the southern portion of our survey area. We had seen some of these individuals already this year (documented either over the Shoals or south of Muskeget Channel); however, there were also several new whales in this aggregation too.  

The movement of right whales in our survey area over these past four months underscores how dynamic right whale movement can be as they follow their prey. But it's not only the specific areas where we find whales that change: the individual whales we see change, too! While we might see a group of whales on every flight in our survey area over several months, that group may be made up of almost entirely different whales each time we fly!

In fact, 77 of the 102 individuals we documented were sighted only once this year, and we didn’t resight any whale more than three times. Of the whales resighted more than once, only one individual appeared to stay in the area for three months, while others stayed one to two months. This rapid turnover of individuals implies consistent movement into and out of the area.


Reuniting with Old Friends

Photo of Musketeer, a right whale
Musketeer (#4360), a regular visitor to Southern New England.

Among the 102 whales we photographed, we were happy to see some old favorites. One of these was Musketeer (Catalog #4360), who is a staple of our aerial surveys and is easily identifiable from the plane by the feather-shaped scar on its head. Since 2019, Musketeer has almost exclusively been documented in Southern New England, including during the late summer and fall when right whales are less common in this area. Whales like Musketeer underscore the importance of conducting long-term, systematic surveys to understand species distribution and occurrence in a rapidly changing climate. While many right whales utilize Southern New England only in the winter and spring months, in the last six years small numbers of right whales have also been documented here in the summer and fall as well.

Making New Friends

We have also noticed some new “faces” this year and have documented twelve individuals that we have not sighted in our survey area since surveys began in 2011. Of these, three are at least 35 years old:

  • Herb (#1250), a 41-year-old male who used to be a regular visitor to the Bay of Fundy, Canada, where he was documented by the vessel-based Kraus Marine Mammal Conservation group. He has not been documented in Southern New England before.
Photo of Herb, a right whale
Herb (#1250) subsurface feeding on April 14, 2023.
Photo of Wolf, a right whale
Wolf (#1703) photographed at the surface on April 14th, 2023.
  • Wolf (Catalog #1703), a 36-year-old female who has not been documented in Southern New England before. Wolf has had four known calves, one of which (Caterpillar, Catalog #3503) is still alive.   
  • Legato (Catalog #1802), a 35-year-old female who has only been documented once in Southern New England, in 2002. She has had four calves: one of her calves, Portato (Catalog #3802), has been documented in Southern New England twice before. 
Photo of Legato, a right whale
Legato (Catalog #1802) photographed in SNE in February, after a 20+ year sighting gap in this habitat.

More to discover

What brings these older whales here for the first time when they have already established long, repeated sighting histories in other areas? Why do others return consistently year after year? How long will they continue to come back? While we usually have lull in right whale sightings during May and June, we look forward to discovering more when the right whales return in the summer and fall! 

All photos taken by NEAq aerial observers on surveys of wind energy areas and surrounding waters sponsored by MassCEC, BOEM and NOAA, under NEFSC Permit #25739.