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From Wired.com:

In the stomachs of tiger sharks in the Gulf of Mexico, researchers are finding something unusual: land-faring migratory birds.

Sharks are known to eat seafaring birds, but land birds such as woodpeckers, meadowlarks, swallows and tanagers are unexpected.

“We’re the first to look this exhaustively at the diet of tiger sharks, as far as I know, and this certainly seems surprising,” said fisheries ecologist Marcus Drymon, leader of an ongoing tiger shark diet study at the Dauphin Island Sea Lab in Alabama.

The American Bird Conservancy thinks the research suggests oil platforms are to blame for dropping migratory birds into Gulf waters. Night-flying birds are known to get trapped in bright light sources, including offshore oil platforms and the 9/11 memorial lights. More than 6,000 illuminated platforms that pepper the Gulf could become giant nighttime bird lures, causing birds to circle in confusion until they’re exhausted, drop into the water and become shark food.

“Unfortunately, we don’t have good baseline data to know that,” Drymon said. “We don’t know if migratory birds are normal things for them to eat or not. There’s no data on tiger shark diet from 100 or 50 or even 30 years ago.”

Migratory land birds in the U.S. typically overwinter in South America and return in the spring or summer. Each leg of the migration is a non-stop flight covering hundreds or even thousands of miles. Threats range from storms and airborne predators to exhaustion and malnutrition.

The birds stay on course in part by using moonlight and starlight to calibrate internal compasses. Human light pollution can interfere with that ancient system, and poses an evolutionarily unique challenge that researchers have just started to study.

These are all interesting theories, but there are a few possible problems with interpreting these facts in this fashion.

First of all, I don’t know how clearly we know that birds use the moon and starlight to migrate.  It has been one of the theories postulated, but I don’t think we have any kind of definitive evidence of how birds migrate.

Tiger sharks are called the garbage men of the sea for a very simple reason:  they will eat anything.  The ones around Hawaii have been found with mongooses in their stomachs.  The small Indian mongoose that was introduced from Jamaica is not an aquatic animal, but whenever there are heavy rains in Hawaii, some mongooses get flushed out to see, where the tiger sharks pick them off.

And anyone who has ever seen Jaws can remember the scene where Hooper dissects a large tiger shark that had been caught by a mob of bounty fishermen.  When Hooper opens up the tiger shark’s stomach, he finds a Louisiana license plate.

The discovery of what appear to be rather large numbers of land-based migratory birds in the stomachs of tiger sharks is really interesting, and it does raise an interesting hypothesis.

Are oil rigs causing the problem with the collapse of so many migratory birds?

Counting the number of birds in tiger shark stomachs is not a very good measure for the reasons I’ve just described.

Further, we don’t know how many land-based birds are normally found inside tiger sharks.

To do the experiment, we’d have to get some analysis from tiger sharks that are found in seas without oil rigs and that exist along major migratory routes for birds.

I don’t know of any regions that meet those criteria.

So it’s an interesting hypothesis, but it is going to require a lot more study to be in any way definitive.

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The documentary is in German, but I don’t know where this was filmed.

Tiger sharks and blue whales are both wide ranging species.

This is not a big blue whale. It’s only about 60 feet long!

Nature isn’t always so nice.

This would be like a human being eaten alive by pack of weasels.

Not a great way to go.

 

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This 1,780-pound tiger shark was caught off North Myrtle Beach, South Carolina in 1964. It was nearly 14 feet long.

The fisherman who caught it was Walter Maxwell of Charlotte, North Carolina.

It was caught on 130-pound-test line, using bait that was taken out 800 yard by boat.

The great fish was finally hauled into the Cherry Grove Fishing Pier after three hours of struggle.

I have spent some time in this part of the world.

Shark fishing from piers is illegal in South Carolina.

Perhaps for good reason.

Tiger sharks provide a vital role in the ocean ecosystem, and we probably shouldn’t be so cavalier about killing them.

But I still think it would have been awesome to see this beast hauled in.

 

 

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The tiger shark is one of the species that does occasionally attack people.

But this footage shows them to have a certain amount of grace and beauty that one might not suspect from a creature known as the “garbage man of the sea.”

They tend to eat just about anything– as you may remember from Jaws. In that film, the amateur bounty fishermen catch a big tiger shark and claim it as the beast that has been terrorizing Amity Island. Hooper, the marine biologist played by Richard Dreyfuss, demands that he cut open the shark to see what it has been eating. He finds a Louisiana license plate inside.

One would expect an animal that eats things like license plates to be very dull and brutish.

But when you look into the eyes of these tiger sharks, you see something one would never expect to see in a fish.

It’s a kind of glimmer of intelligence.  It’s not quite mammalian, but it’s  more of a spark than one would find in a largemouth bass or a bluegill.

Tiger sharks are one of the species targeted by shark finners, and in North American waters, they have been heavily persecuted.

I remember seeing one when I was a small boy. It has been captured by a charter fishing boat that had seen the shark devouring a loggerhead sea turtle. (Tiger sharks are excellent sea turtle predators. Sea turtles are one of their favorite prey items.)

The boat’s captain had seen the shark eating the turtle, but he decided to not to catch it.

They didn’t have a very good day out pursuing billfish, so on their way back, they cast lines for the shark. They snagged it, and after a struggle, they hauled it in.

They had not caught a great blue marlin that day.

The fishermen had been failures.

But now they had tangled with a murderous beast of prey.

They had vanquished the great sea monster, and now they could come back to port as heroes.

Knowing that such a creature could live in the water in which people swam scared me a bit. When I was younger, I used to have dreams about being attacked by a big shark that grabbed me with its jaws in the surf.

Even today, I won’t swim in murky ocean water off the coast. I don’t mind swimming in clear ocean water– one of my favorite days was when I went snorkeling in Hawaii.

But I won’t get in the water if I can’t see to the bottom.

However, as I look at the spark in the eyes of these tiger sharks, they seem less scary, less menacing.  I feel for them in the way I have felt for wolves and other terrestrial carnivores.

Just as the land needs tigers and wolves, the ocean will need tiger sharks.

That tiger sharks sometimes attack people should not given us license to exterminate them.

Look into those eyes, and the being that is a tiger shark is revealed.

A commonality is there.

I just didn’t expect it.

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“This is unknown territory for me. I’m goin’ in!”

Source.

As much as people criticized this show, I have to admit loving it.

By Crikey!

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This is not a big fish tale.

The the claims about the size of the even larger shark that swam off with the gaff in its gills probably are exaggerated.

I’m kind of surprised that after all of that work reeling in the monster, they simply found some place to bury it.

And of course, it raised such a funk that it had to be exhumed.

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