Aquarium scientists spot 31 right whales in shipping lanes off Massachusetts coast

Whale sightings triggered an alert for mariners to slow down

Right whale 4617 and 3503 Caterpillar skim feeding
Right whales “Caterpillar” (Catalog #3503) and Catalog #4617 feeding in the Great South Channel on Feb. 20, 2024. CREDIT: New England Aquarium, taken under NMFS permit #25739

BOSTON, MASS. (Feb. 26, 2024) – Mariners are being asked to slow down after a New England Aquarium aerial survey team sighted 31 North Atlantic right whales in shipping lanes east of Nantucket.


The aerial survey plane was flying over the Great South Channel on Feb. 20 when Aquarium scientists onboard spotted a group of right whales surface feeding about 35 miles east of Nantucket. About four hours later, a second group of right whales was seen 20 miles east of Chatham, MA, which included a surface active group. Over the course of the six-hour flight, 31 individual right whales were identified in the area, which overlaps with shipping lanes into and out of Boston.

One of these right whales was an adult female named “Caterpillar” (Catalog #3503), whose name comes from a large scar on her back that she received as a result of a vessel strike seven years ago.

“Right whales only surface feed under specific conditions, so we felt really lucky to document them this winter. Many of the whales identified so far are adults, including several calving females who have given birth in recent years,” said Katherine McKenna, Assistant Research Scientist in the Anderson Cabot Center for Ocean Life at the New England Aquarium who was aboard the flight.

An aerial survey team from the National Oceanic and Atmospheric Administration’s (NOAA) Northeast Fisheries Science Center first sighted the aggregation of right whales on Jan. 31 and has been monitoring the group in the Great South Channel since then.

The Feb. 20 whale sightings triggered NOAA to extend a voluntary slow speed zone, called a Dynamic Management Area (DMA), for mariners to reduce their speed to 10 knots to protect the whales. The DMA is in effect until March 7, one of several active voluntary slow zones from Maine to Virginia due to right whale sightings. These protections are particularly important given the recent loss of two female right whales—one found off of Georgia after being struck by a vessel.

The location of the whale sightings, which extended a voluntary slow speed zone.
The location of the whale sightings, which extended a voluntary slow speed zone. COURTESY: NOAA

During their flight, the Aquarium survey team also sighted humpback, fin, and minke whales.

The New England Aquarium regularly conducts aerial surveys looking for right whales and other marine animals in southern New England, coastal Maine, and the Gulf of Maine. These flights help monitor changes and recognize trends in where right whales are found. Determining where right whales are and how they are using habitats provides crucial information that can be used to better protect the critically endangered species. The feeding aggregation in the Great South Channel was unexpected at this time of year.

“We know a lot about right whales, but they still surprise us all the time,” said Orla O’Brien, an associate research scientist in the Aquarium’s Anderson Cabot Center who leads the aerial survey team. “While historically the Great South Channel has been a hotspot for feeding whales, it is unusual to see them there during the winter. That makes the work of aerial surveys important in documenting this sighting, especially as the whales are surface feeding in the middle of a shipping lane.”

The Great South Channel is subject to a mandatory slow zone for boats and ships, known as a Seasonal Management Area (SMA), between April 1st and July 31st—meaning whales sighted there outside of this time are only protected by temporary voluntary measures. While voluntary measures are better than no measures at all, research indicates that little cooperation with voluntary measures contributes to their lack of effectiveness.

NOAA is currently considering modifications to the existing vessel speed rule to better protect the critically endangered North Atlantic right whale, whose population is estimated at less than 360 individuals. Proposed changes to the federal vessel speed rule include expanding the size of the areas covered; increasing the time period for those areas with existing seasonal speed restrictions; extending restrictions to include most vessels measuring 35 to 65 feet in length; and implementing mandatory speed restrictions in the above-mentioned DMAs, which are established when and where whales are observed and are likely to remain.

The Aquarium testified before Congress to support these scientifically sound and urgently needed revisions in NOAA’s proposed vessel speed rule. NOAA published the proposed rule 18 months ago. The Aquarium urges the Biden-Harris Administration to release a final rule immediately, and for Congress to allow its implementation.


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