Turning the Tide: Understanding whale migrations

Fri, 11/08/2019 - 6:00am

Marine mammal species, including whales and dolphins, have occasionally been found by the island’s coasts. Certain species, such as the humpback whale, have migration routes that pass by Block Island.

Humpback whales, one of the most common species along New England’s coasts, are known for holding the longest migration distances: over 5,000 miles will be traveled between high-latitude summer feeding grounds, and winter mating and calving grounds in the tropical waters. North Atlantic humpback whales will spend their winter months in the Caribbean, mating and calving. There are few to no food options for humpbacks in this area, and whales will travel up north to feed on small fish and zooplankton for their summers. Feeding grounds have included the Massachusetts coast, specifically Cape Cod where the waters are rich in food diversity. Humpbacks will continue to travel farther up north, to Maine, Newfoundland and even Iceland, where bodies of waters will mix and provide rich nutrients for zooplanktons and small fish.

The humpback whale is not the only baleen whale to migrate past New England coasts. Baleen whales are generally larger than toothed whales, and have baleen plates in their mouth, which help filter seawater from inside their mouths to trap their prey. Their baleen plates are composed of keratin, the same protein that makes up our fingernails and hair. Right whales, fin whales, and minke whales have been spotted near the offshore wind farm. Similar to humpback whales’ migration routes, right whale mothers and their calves will migrate from the south up to Cape Cod to feed. During the planning stages of the offshore wind farm, North Atlantic right whales’ routes were taken into consideration, to avoid disturbing their space and to ensure they wouldn’t be harmed; these whales are an endangered species, with less than 400 remaining in the world due to vessel strikes and entanglements.

When it comes to spotting a whale, there are multiple ways to collect observations. Humpback whales, and most baleen whales, are identified for their dorsal fins and flukes (tails). The dorsal fin is located on the top of the whale, usually farther down the spine and has a “hump” shape. Scratches, hue patterns and notches can be found on their fins for identification strategies.

The fluke is the whale’s tail, and can be identified by various color markings and scratches. Humpback flukes are unique and quite similar to the human fingerprint. No two flukes are the same, and therefore no two humpback whales can be the same. Any scratch marks, notches and scars are key identifiers in singling out and remembering a whale. Whales can also be identified from hue variation, as well as patterns found on their bodies.

If you were to find a whale stranded or deceased on the island, there are numbers and places you can report to and send in photos of strandings:

NOAA Fisheries numbers:

Regional: Northeast Marine Mammal and Sea Turtle Stranding and Entanglement Hotline

Phone: (866) 755-NOAA (866-755-6622)

For marine mammals and sea turtles (Connecticut/Rhode Island):

Mystic Aquarium

Phone: (860) 572-5955 x 107

Block Island:

The Nature Conservancy

(401) 466-2129

Reporting apps for Android and Apple phones:

Whale Alert (NOAA)

Dolphin & Whale 911 (NOAA)