Friday, October 2, 2009

A potential endangered whale shuffle

There's talk about moving one Hawaiian whale on and one Hawaiian whale off the federal Endangered Species List.

Why? Humpbacks have recovered nicely since being protected, while the Hawaiian inshore population of false killer whales is dropping to near 100 individuals.

(Image: humpback whale numbers have recovered, but they still face threats. This whale off Maui last year, was entangled in multiple lengths of polypropylene line. Credit: NOAA)

The humpback whale, for which the Hawaiian Islands Humpback Whale National Marine Sanctuary was designated just a dozen years ago, has recovered dramatically in numbers since whaling for it was technically halted by an international ban back in 1966.

Humpbacks had dropped in number to between 1,000 and 2,000. Now their number is estimated at more than 20,000 in the North Pacific.

The sanctuary, of course, is for more than just whales, and its survival should not be threatened by the downlisting of Hawai'i's most visible whale species. More information on the status review for humpbacks here

That site includes information on how to comment on the status of the whales. Deadline for comment is Oct. 13. More on this below.

Meanwhile, the Natural Resources Defense Council is calling for the endangered species listing of another Hawai'i whale, the Hawaiian false killer whale.

Most folks have seen humpbacks, because of their remarkable aerial acrobatics, sometimes leaping their tons upon tons entirely out of the water.

Most have never seen Hawaiian false killer whales, Pseudorca crassidens, which are large dolphins that can reach three-quarters of a ton in weight. These animals tend to be deepwater creatures, but there is a genetically distinct Hawaiian population that remains close to shore.

There are only about 120 of them, and the population has been declining for the last quarter century—the same time during which humpbacks have been rebounding.

“Given the extremely small size of this population, the loss of even a few mature adults could have serious and long-term reproductive consequences. Toxic chemicals, reduced food sources and interactions with fishing vessels are the biggest threats to this unique mammal,” said NRDC wildlife biologist Sylvia Fallon.

In a press release, the organization adds these points:

“The population faces a number of threats including interactions with local fisheries, reduced food sources and exposure to toxic chemicals. False killer whales are likely affected both by long-line and unregulated near-shore and “short” long-line fisheries. A recent study showed that disfigurement from fishing gear in this population was four times higher than for other dolphin and toothed whale species, suggesting high rates of interactions with fisheries. These fisheries may also be contributing to a decline in the size or number of the primary food source for false killer whales, which are large deep water fish including mahi mahi and yellowfin tuna.

“Recent research confirms the presence of PCBs (a toxic substance found in plastics), DDT and flame retardants in tissue samples taken from the Hawaiian false killer whales. Pollution levels found in one-third of the samples are known to cause serious health problems in marine mammals.

“The cumulative effects of these risks combined with the depleted population qualify the Hawaiian false killer whale as an endangered species under the federal Endangered Species Act. If listed, the population would become the first Hawaiian toothed whale species listed under ESA and only the second toothed whale (after the southern resident killer whale in the Pacific Northwest) listed overall. Today’s petition was sent to the Secretary of Commerce through the National Marine Fisheries Service.”

This site has images of major whale species and the threats they face,

© Jan TenBruggencate 2009

If you choose to comment on the listing status of humpback whales, here's the contact information from the Federal Register:

DATES: To allow us adequate time to conduct these reviews, we must
receive your information no later than October 13, 2009. However, we
will continue to accept new information about any listed species at any time.

ADDRESSES: You may submit comments, identified by the code 0648-XQ74,
addressed to Shannon Bettridge by any of the following methods:
1. Electronic Submissions: Submit all electronic comments via the
Federal eRulemaking Portal
2. Facsimile (fax): 301-713-0376, Attn: Shannon Bettridge.
3. Mail: Shannon Bettridge, National Marine Fisheries Service,
Office of Protected Resources, 1315 East-West Highway, Silver Spring,
MD 20910.

FOR FURTHER INFORMATION CONTACT: Shannon Bettridge at the above
address, or at 301-713-2322.


Dolphin said...

Excellent, very informative. Keep up the good work!!!

Dolphin said...

Excellent, very informative. Keep up the good work!!!