This common fishing practice endangers an entire whale species

So many North Atlantic right whales have collided with boats or become ensnared in vertical trap lines that only 400 of the animals remain.

This story appears in the October 2019 issue of National Geographic magazine.

When North Atlantic right whales migrate along North America’s eastern seaboard, they run a gantlet of fishing lines in their path. Today 83 percent of the population shows signs of entanglement, a leading cause of death for this endangered species. Fishing for crab and lobster involves placing traps (also called pots) on the ocean floor and marking the spot with a surface buoy that’s connected to the traps with a sturdy line. But the lines routinely harm whales; they cut into flesh and impede the whales’ diving, surfacing for air, and feeding. To CT Harry of the International Fund for Animal Welfare, a remedy seems clear: “Fishing without vertical lines is what’s going to save this species.”

ENCOUNTERING TRAPS

Right whales, which see mostly in black and white, often don’t notice crab or lobster traplines until they hit one. When they try to move on, the line may get tangled around their fins or open mouths.

ROLLING AND TUMBLING

Scientists at the Consortium for Wildlife Bycatch Reduction simulated what happens when a whale hits a trapline: The animal rolls and spins, unintentionally winding the line around its body.

DEATH OR IMPAIRMENT

Whales tangled in lines can have trouble reproducing, drown, or starve to death. A recent study attributes nearly 60 percent of diagnosed North Atlantic right whale deaths over a 15-year period to entanglement.

FISHING WITHOUT LINES

Ropeless solutions are commercially available in Australia and in pilot projects in U.S. and Canadian waters. To retrieve the catch, fishers send an acoustic signal to the apparatus, triggering either the rope or the entire trap to rise to the surface.

Fishing

boat

Acoustic

signal

Apparatus

rests on

seafloor

Acoustic signal

triggers release of

apparatus to surface

NORTH ATLANTIC RIGHT WHALE RANGE

North Atlantic right whales live

chiefly in western Atlantic coastal waters or close to the continental shelf. Six died in June 2019; some 400 are left, fewer than 100 of them breeding females. Absent changes, the population could be functionally extinct within a few decades.

Historic North Atlantic

right whale range

(Eubalaena glacialis)

Historic North Atlantic

right whale range

(Eubalaena glacialis)

Historic North Atlantic

right whale range

(Eubalaena glacialis)

Atlantic

Ocean

Atlantic

Ocean

DIANA MARQUES, NGM STAFF. TANIA VELIN.

ART: JOE McKENDRY

SOURCES: INTERNATIONAL FUND

FOR ANIMAL WELFARE; IUCN

ENCOUNTERING TRAPS

Right whales, which see mostly in black and white, often don’t notice crab or lobster traplines until they hit one. When they try to move on, the line may get tangled around their fins or open mouths.

Vertical lines

A line runs from a buoy on the surface to the seafloor, where it connects as many as 40 lobster traps strung at intervals along the line. The apparatus can weigh more than 2,500 pounds.

ROLLING AND TUMBLING

Scientists at the Consortium for Wildlife Bycatch Reduction simulated what happens when a whale hits a trapline: The animal rolls and spins, unintentionally winding the line around its body.

DEATH OR IMPAIRMENT

Whales tangled in lines can have trouble reproducing, drown, or starve to death. A recent study attributes nearly 60 percent of diagnosed North Atlantic right whale deaths over a 15-year period to entanglement.

NORTH ATLANTIC RIGHT WHALE RANGE

North Atlantic right whales live

chiefly in western Atlantic coastal waters or close to the continental shelf. Six died in June 2019; some 400 are left, fewer than 100 of them breeding females. Absent changes, the population could be functionally extinct within a few decades.

FISHING WITHOUT LINES

Ropeless solutions are commercially available in Australia and in pilot projects in U.S. and Canadian waters. To retrieve the catch, fishers send an acoustic signal to the apparatus, triggering either the rope or the entire trap to rise to the surface.

Fishing

boat

Historic North Atlantic

right whale range

(Eubalaena glacialis)

Historic North Atlantic

right whale range

(Eubalaena glacialis)

Historic North Atlantic

right whale range

(Eubalaena glacialis)

Atlantic

Ocean

Atlantic

Ocean

Acoustic

signal

Acoustic signal

triggers release of

apparatus to surface

Apparatus

rests on

seafloor

DIANA MARQUES, NGM STAFF. TANIA VELIN. ART: JOE McKENDRY

SOURCES: INTERNATIONAL FUND FOR ANIMAL WELFARE; IUCN