Monterey Bay researchers say dolphins are causing porpoise deaths

San Jose Mercury News ^ | 6 November 2009 | Alia Wilson

[CounterCounterCulture]

Monterey Bay researchers say dolphins are causing porpoise deaths

For the past five years, the growing number of dead harbor porpoises washing up on California shores has been a marine mystery — until now.

In September, marine biologists with Okeanis, a nonprofit conservation group based in Moss Landing, captured the only video footage taken in Monterey Bay of bottlenose dolphins attacking and killing a porpoise.

Scientists suspected dolphins, which have a relatively docile reputation, have been attacking the smaller porpoises because the porpoises have been washing up on the shore with rake marks and internal bleeding, but they never had any proof.

"Now we know the how, but we still are unsure of the why," said Daniela Maldini, president of the Okeanis board. "We have been observing the social structure of these animals and it has taken us 20 years to do that. This type of behavior is something new." Maldini has been monitoring the same group of about 600 dolphins since 1990. Maldini said Okeanis believes in collecting a variety of data before problems arise to better diagnose critical changes in the environment. But what they captured raises more questions than supplies answers.

The video shows a group of male dolphins using several techniques to assault a porpoise as it tries to get away. The dolphins corral the porpoise, ram it with their beaks, scrape or rake it with their teeth and drown the porpoise by jumping on top of it. The dolphins then bring the carcass up to the Okeanis researchers, watch them bring it on board and then swim away.

[CounterCounterCulture]

Oh noes!

[CounterCounterCulture]

[CounterCounterCulture]

South Park ping-worthy?

The Japanese know about those evil dolphins.

[Gaffer]

Intraspecies Hate Crimes

[MediaMole]

Dolphins are killing them on porpoise?

[dfwgator]

Nice to see the dolphins have found a porpoise in their lives.

[Yossarian]

These killer dolphins could only have existed as a result of the U.S. Navy’s evil “Marine Mammal Program”.

/S

[dfwgator]

So Long and Thanks For All The Porpoises.

[Tribune7]

The dolphins then bring the carcass up to the Okeanis researchers, watch them bring it on board and then swim away.

Seems like they think the porpoises are spies for men.

[JoanneSD]

I was thinking this must be ex POTUS Bush’s fault..

[Vendome]

I don’t think they are doing it on porpoise.

[FrankR]

"...dolphins attacking and killing a porpoise"

Uh-oh...the democrats will be forming a committee and a sub-committee, and appointing two new "dolphin" Czars in the obama cabinet to investigate and pass a "Porpoise Stimulus Bill" to redistribute the bait fish from the racist dolphins to the oppressed porpoises.

A porpoise task force will have to be formed and funded by taxing the rich (dolphins).

Obama will make a trip to Sea World to lay out his proposals for dealing with these racist dolphins and proposing government healthcare benefits are all porpoises injured in these attacks.

Rahm Emmanuel said, "It's a disaster we can't afford to waste.". Film at eleven...

[Dr. Bogus Pachysandra]

Sonar makes them do it!

[DallasDeb]

Maybe the dolphins, observing the researchers observing the porpoises, thought that the researchers wanted the porpoises, so they gave them to the researches.

[DallasDeb]

Or, maybe there are now dolphin gangs.

[ansel12]

on porpoise?

[NativeSon]

Scientists suspected dolphins, ...

I've known it all along, what with all the bottle-nose bruises or blow hole burns on the victims

[TASMANIANRED]

Dolphin yutes.

[Marty62]

Oh now we know the Porpoise were calling the Dolphins bad names.

[Winged Hussar]

Dolphins and porpoises eat the same food (fish). It’s possible that the dolphins are eliminating their competitors, the same way humans eliminate wolves and other carnivores that eat what we want to eat.

[garbanzo]

"Now we know the how, but we still are unsure of the why,"

Drugs, welfare, fatherlessness, moral decay, secularism, liberal dolphin mass media and lack of federal spending on dolphin inner cities.

[Cyber Liberty]

... dolphins, which have a relatively docile reputation ...

Tell that to the sharks.

[Chode]

[dfwgator]

This never would have happened if they hadn’t banned tuna nets.

This message brought to you by Weemsco Tuna. (”The Tuna Doesn’t Taste as Good as It Used To.”)

[Carry_Okie]

Dolphins and porpoises eat the same food (fish). It’s possible that the dolphins are eliminating their competitors, the same way humans eliminate wolves and other carnivores that eat what we want to eat.

Read the whole article. Seals and sea lions are their principal competitors and the dolphins are not attacking them.

[Carry_Okie]

The video shows a group of male dolphins using several techniques to assault a porpoise as it tries to get away. The dolphins corral the porpoise, ram it with their beaks, scrape or rake it with their teeth and drown the porpoise by jumping on top of it. The dolphins then bring the carcass up to the Okeanis researchers, watch them bring it on board and then swim away.

This research has been continuous for nearly twenty years with the same boat going out to see the same schools of dolphins. My guess is that these people have relationships with the dolphins; i.e., they probably know each other and are on friendly terms, recognizing individuals, possibly tossing an occasional fish, etc from their rather impressive (to a dolphin) watercraft.

Wouldn't it be ironic if this were some sort of induced reciprocal offering on the dolphins' part, that they were bringing food to the researchers? If the behavior is unprecedented and unique, and so is the research...

[Randy Larsen]

Crap!

My taxes are going up again to save another GD fish!