Dolphins Dead off Zanzibar - Is Navy Sonar to Blame?

Categories

Health

Technology

Some four hundred dolphins have been found dead along the shore of a tourist destination on Zanzibar's northern coast. Villagers, fishermen and hotel residents found the dolphins' carcasses on Friday and alerted officials. What killed the dolphins is not clear, though scientists ruled out poisoning.

The Sunday Times in its report about the incident says

"Experts are investigating the possibility that sonar from US submarines could have been responsible for a similar incident in Florida in March. The US Navy patrols the East Africa coast."

In November last year, Truthout reported that the United Nations Environment Program issued a report that said high-intensity naval sonar poses a serious threat to whales, dolphins and porpoises that depend on sound to survive. The article goes on to say:

The study lends the first official support to claims by environmental groups that military manoeuvres are responsible for the increasing incidence of mass whale beachings. "We know about other threats such as over-fishing, hunting and pollution [but] a new and emerging threat to cetaceans is that of increased underwater sonars," said Mark Simmonds, of the Whale and Dolphin Society. "These low-frequency sounds travel vast distances, hundreds if not thousands of kilometres from the source."

The American Navy is up-beat about their new sonar, which gives great underwater visibility of targets and everything else, and they say that care was taken not to disturb the sound-sensitive creatures of the sea. But apparently the sonar makes use of such high volume sound blasts that underwater creatures cringe and perhaps worse - die a painful death when they are hit with the noise at close range.

Stories of dolphins and whales either dying or throwing themselves on beaches in groups are fairly frequent in recent times, but so far, proof of what exactly panics the whales and dolphins is elusive.

Just one week ago, 25 dead dolphins were found in the Black Sea on the Bulgarian coast.

In March, 60 Bottlenose Dolphins were found killed in the waters of the Florida Panhandle. Although toxic algae were cited as a possible contributing factor, they seem an unlikely explanation for the sudden death.

Clearly, some detective work is needed. Autopsies? Why not. Looking into the Navy's scientific assessment? Yes!. After all, Dolphins are said to be the second most intelligent species on this planet next to us humans.

What gives us the right to disregard their dignity and disrespect their lives? How would we feel if we discovered that an apparently "superior" race of aliens were killing humans as if nothing were wrong with that? It works both ways!

Please help put pressure on your government to

1) find out why cetaceans are dying a horrible death in great numbers and

2) raise international awareness of the need to protect life - even if it's not of our own species.

For the record, here is the article that caught my eye and that describes the finding of more than 400 dead dolphins off Zanzibar.

- - -

Mystery over 400 dead dolphins

Saturday 29 April 2006
(original article here)

Hundreds of dolphins have been found dead along the shore of a tourist destination on Zanzibar's northern coast.

Villagers, fishermen and hotel residents found the dolphins' carcasses on Friday and alerted officials.

It was not immediately clear what killed the 400 dolphins, though scientists ruled out poisoning.

Narriman Jidawi, a marine biologist at the Institute of Marine Science in Zanzibar, said their carcasses were strewn along a 4km stretch of Nungwi.

But the bottleneck dolphins, which live in deep offshore waters, had empty stomachs, meaning that they could have been disoriented and were swimming for some time to reorient themselves.

They did not starve to death and were not poisoned, Jidawi said.

Investigation

In the United States, experts were investigating the possibility that sonar from US submarines could have been responsible for a similar incident in Marathon, Florida, where 68 deep-water dolphins stranded themselves in March 2005.

A US navy task force patrols the East Africa coast.

A navy official was not immediately available for comment, but the service rarely comments on the location of submarines at sea.

The deaths are a blow to the tourism industry in Zanzibar, where thousands of visitors go to watch and swim with wild dolphins.

The Indo-Pacific bottlenose, humpback and spinner porpoises, commonly known as dolphins, are the most common species in Zanzibar's coastal waters, with bottlenose and humpback dolphins often found in mixed-species groups.

- - -

Not directly related to this particular incident, there is a report on the Washington Post on an earlier stranding of whales in a Hawaiian bay that implicates Navy sonar as the probable cause:

Sonar Called Likely Stranding Cause

Original in Washington Post
Friday, April 28, 2006; Page A08

Federal marine specialists have concluded that Navy sonar was the most likely cause of the unusual stranding of melon-headed whales in a Hawaiian bay in 2004.

The appearance of as many as 200 of the normally deep-diving whales in Hanalei Bay in Kauai occurred while a major American-Japanese sonar training exercise was taking place at the nearby Pacific Missile Range Facility.

The report is the latest in a series of scientific reviews linking traditional mid-frequency naval sonar to whale strandings. Sonar has been used for decades, but it was only recently that the apparent connection to strandings was established.

While the National Oceanic and Atmospheric Administration scientists said they could not definitely state that sonar caused the strandings, they said extensive study led them to the conclusion that there was no other likely cause.

"Our analyses indicate there was no significant weather, natural oceanographic event or known biological factors that would explain the animals' movement into the bay nor the group's continued presence in the bay," said Teri Rowles, NOAA Fisheries Service's lead marine mammal veterinarian and lead author of the report.

NOAA concluded that sonar was "a plausible, if not likely, contributing factor" to the stranding.

The Navy has said it was virtually impossible for its sonar to have led to the Hanalei Bay stranding, and officials maintained that position yesterday. "I think that if you look at the report, there are just so many unknown factors at work that to say sonar was a plausible if not likely cause is erroneous," said Lt. Commander Christy Hagen of the U.S. Pacific Fleet in Hawaii.

The Navy is planning another major sonar testing maneuver in the same area in July and -- for the first time -- NOAA has formally asked the Navy to use expanded measures to protect whales from the possible effects of its sonar.

The active sonar used by navies sends out loud pings of sound that seem to frighten and disorient whales, especially deep-diving species such as the beaked and melon-headed whales. The effect was documented off Greece in 1996 and established later during naval exercises in the Bahamas, off the Canary Islands and off Spain.

The findings have complicated the Navy's efforts to set up a 500-square-nautical-mile sonar training facility off the coast of North Carolina. Naval officials say the sonar training is essential, especially now that possibly hostile foreign navies have developed diesel submarines that are not detected by the kind of passive sonar used to follow large nuclear submarines.

Rowles said that the melon-headed stranding in Hawaii was highly unusual, and only the second recorded in the United States in modern times. The other occurred off Florida earlier this year, and Rowles said NOAA is trying to determine if any naval activity occurred in the area.

In the 2000 Bahamas stranding, a local marine biologist collected some of the whales that died onshore and froze them for later study -- which helped NOAA conclude that sonar was the likely cause. In Hanalei Bay, the whales were ultimately led back to sea and one young animal died, apparently of starvation. So there was no physical evidence of injury to examine.

Yesterday's NOAA conclusion was based instead on the lack of other possible causes, the unusual nature of the whale movement, and an analysis that concluded the extensive sonar use occurred close enough to Hanalei Bay for the whales to swim there by early July 3.

A number of environmental groups have become increasingly concerned about the effects of sonar, and the Natural Resources Defense Council has sued the Navy a number of times on the issue. Michael Jasny, a senior consultant with NRDC, said the NOAA report was worrisome.

"This was by far the largest stranding of melon-headed whales ever recorded in Hawaii," he said. "Once again, the Navy's denial has been contradicted by the official government investigation. It's time for the Navy to stop this needless infliction of harm."

See also:

Mass dolphin deaths off Zanzibar a mystery: scientists
A team from the Zanzibar-based University of Dar es Salaam's Institute of Marine Sciences said a preliminary investigation into the mass stranding of nearly 600 bottlenose dolphins had failed to yield an explanation. "We have net yet been able to determine what has exactly caused the strandings," it said in a report. "We are still doing more investigation and ... in a few weeks' time we may come out with some answers."

What's in a name? Ask a dolphin
Bottlenose dolphins can call each other by name when they whistle, making them the only animals besides humans known to recognize such identity information, scientists reported Monday.

Flipper! Dolphins know each other by name
They might not yell out "Flipper!", but dolphins know each other by "name", according to a new study. Scientists have speculated for years that bottlenosed dolphins' whistling transmitted more identity information than the communications of other animals, which can often express species and group identity. But in the study published Monday in the Proceedings of the National Academy of Sciences, scientists said they determined that dolphins communicate in a more sophisticated way than other animals, expressing and understanding specific "names" more in the way humans do.

3 July 2006: T Washington Post carries an article on a legal case against Navy use of sonar.
Whale Concerns Halt Use of Navy Sonar
LOS ANGELES -- A federal judge on Monday temporarily barred