Wednesday, March 7, 2012

Stressing Out Right Whales

Right whales come to the Bay of Fundy
in late summer to feed.
Research indicates that North Atlantic right whales, which are New Jersey's rarest whale species, are showing greater stress because of increasing ocean noise.
We overlook some of our marine species because they are not frequently seen. We don't think of whales as "living in New Jersey" but if you look at the list of endangered mammals for NJ, 6 of the 9 species are whales. You may need to remind children (and some adults!) that whales are mammals.
Bat, Indiana**
Myotis sodalis**
Lynx rufus
Eubalaena glacialis**
Whale, blue**
Balaenoptera musculus**
Whale, fin**
Balaenoptera physalus**
Whale, humpback**
Megaptera novaeangliae**
Whale, sei**
Balaenoptera borealis**
Physeter macrocephalus**
Woodrat, Allegheny
Neotoma magister
**Federally Endangered

These whales are under the state's protection primarily during the seasons when they migrate up or down the Atlantic coast. North Atlantic right whales (Eubalaena glacialis) roam up and down the east coast of North America, coming to the Bay of Fundy typically in late summer to feed.

In an article from the BBC:
Ships' propellers emit sound in the same frequency range that some whales use for communicating, and previous studies have shown the whales change their calling patterns in noisy places. Now, researchers have measured stress hormones in whale faeces, and found they rose with the density of shipping.

The species studied in the Bay of Fundy in Canada, the North Atlantic right whale, is listed as endangered. It had been thought that hunting by the Basque people a few hundred years ago brought a robust population down to barely sustainable levels. But recent research suggests the big population decline happened much earlier, for reasons that are unclear.
Whales (particularly mothers and calves) communicate
using low frequency sounds
Ocean noise has risen substantially in recent decades along with the growth in global shipping. For example, one analysis showed that the north-eastern Pacific is 10-12 decibels louder now than in the 1960s.

Significant numbers of right whales are hit by ships and entangled in fishing nets and it is hard to determine how much of a factor noise is in affecting whales' communication and navigation.

One successful effort in the Bay of Fundy has been in relocating shipping lanes away from the feeding grounds. This has reduced ship strikes by 80-90%, while similar measures have been taken elsewhere along the coast.

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