Tag Archives: fish

In This Small Brazilian Town, Dolphins and Fishermen Work Together (Video)

On the Brazilian coast, a couple hundred miles south of São Paulo, lies the small town of Laguna.

Laguna is very much like most other small coastal towns in Brazil, with many people relying heavily on fishing to provide both food and income.

However, the fishermen of Laguna have a truly remarkable secret weapon: a pod of about 20 bottlenose dolphins. Check it out in this awesome video from the BBC series Human Planet:

This interaction is a beautiful example of a symbiotic relationship, one in which both species benefit from cooperation.

The dolphins help the fishermen by herding fish into shallower waters along the shore. Once the fish are bunched, the dolphins use specialized head or tail slaps to show the fishermen where to cast their nets.

Not only does it make fishing much easier and more effective, it also saves the fishermen the trouble of having to go out into deeper waters to find fish.

A fisherman responds to a dolphin’s cue by casting his net. Click to enlarge (Photo: Fábio Daura-Jorge)

When the fishermen cast their nets, it startles the schools of fish, causing them to split up and swim in random directions. This makes it much easier for the dolphins to pick them off as they try to escape.

The dolphins help provide fish to over 200 families in Laguna who have no other source of income.

Over the years, the fishermen have become  intimately familiar with many of the dolphins, even naming them. Some of the most skilled dolphins, like “Scooby” and “Caroba”, have been working with the fishermen for more than 15 years.

The dolphins herd schools of mullet towards the shore where they can be easily collected by the fishermen. Click to enlarge (Photo: Fábio Daura-Jorge)

Recently, a group of researchers decided to study the unique interactions.

Fábio Daura-Jorge, who works at the University of Santa Catarina in Brazil, was one of the leading researchers.

He pointed out that although this relationship is very unique, it’s not altogether surprising when you consider how social dolphins are as a species:

“Dolphin societies are very complex, and social interaction seems to drive foraging behavior…

It might be that the development of specialized foraging behavior occurs in small tight-knit resident coastal communities because there is a high degree of social interaction between the animals.”

Fábio Daura-Jorge played a key role in the study of Laguna’s dolphins, and also did some photography while he was there. Click to enlarge

He also stressed just how important the dolphins are to the way of life for the fishing families of Laguna:

“The fish provided from the cooperation with dolphins has an important economic and social value that has to be considered…

Essentially, if we lose the cooperative dolphins, we lose this unique traditional way of life and vice versa.”

Read more from Live Science here.

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Check Out This Rare Baby Albino “Cyclops” Shark (Photo Gallery)

I’ll address all skeptics immediately, this is a real dusky shark fetus that was caught inside its mother in 2011 along with nine other normal baby sharks. Unfortunately the mother died when it was caught so none of the babies survived.

In 2011,Tracy Ehrenberg, general manager of Pisces Sportfishing in Cabo San Lucas, interviewed the fisherman who made the catch in the Sea of Cortez, southeast of La Paz, Mexico.

With so many shark species struggling to survive because of the shark finning industry, it’s unfortunate to lose a mother shark with ten offspring. However, Ehrenberg points out,

“It’s kind of sad to see a female with pups inside killed but this was taken by a commercial fishing skiff and this is how this fisherman makes his living. All parts of the shark are used, including the skin. The meat is salted and sent to mainland Mexico, where it is usually sold as bacalo or ‘cod.'”

Shark with Litter
Shark with Litter

When pictures of the shark first emerged online, the images went viral and skeptics all over declined the possibility of this being a real catch. Even the fisherman who made the catch was amazed, and to this day keeps the fish in preservation and refuses to sell it.

The story became more believable after Felipe Galvan, a prominent Mexican scientist, acknowledged that he had inspected the shark and wrote a paper describing the fish’s strange appearance as the result of,

“a rare congenital malformation, resulting from the division of the embryonic brain that leads to fusion of the eyes to form a single, central eye.”

This fish is certainly one of the strangest creatures I have ever seen. Check out more pictures below. Click an image to enlarge:

Using Vacuum Tubes to Shoot Salmon Over Dams and Restore Their Traditional Habitats

Over the past hundred and fifty years or so, the waterways of the Pacific Northwest have seen more and more dams built across them.

The dams provide hydroelectric power, as well as making irrigation possible in otherwise dry, arid areas.

But they have also contributed to the rapid decline of the once thriving salmon populations of the region.

Columbia River Basin: fish and dams. Click to enlarge

The Columbia River Basin is a series of rivers which used to empty out into the Pacific Ocean. Young salmon would head out towards the ocean to mature while older salmon headed back to their home rivers and streams to mate and spawn.

But since the first hydroelectric dam in the Pacific Northwest was built in Spokane in 1885, the region has seen over 40 dams built along the waterways that make up the ancient salmon habitats.

Thirteen salmon species are listed as endangered and a number of otherds have already gone extinct.

One of the problems is that many dams lack fish ladders, which are basically series of steps that allow fish to get from one side of a dam to the other. This cuts off hundreds of miles of habitat to endangered salmon as well as their close relatives, the steelhead trout.

A fish ladder alongside the John Day Dam, on the Columbia River. Click to enlarge

Many people argue that these fish ladders are almost completely ineffective. One study showed that only 3% of fish that make it past the first fish ladder in a series of dams will reach the last one. The ladders are also not big enough to accommodate larger fish species like sturgeon.

But now, a team of biologists in central Washington has come up with a creative solution to this problem: vacuum-pressurized tubes.

The idea originated in 2009 with Whooshh Industries, a Washington-based company that started out making vacuum tubes for fruit transportation and harvesting.

Courtesy of Whooshh Industries. Click to enlarge

The concept was tested early last month. Biologists used Whooshh’s 40-foot flexible vacuum tubes to transport 90 salmon from a collection area to a tank truck waiting to transport them to a hatchery.

The biologists say that the tubes are less stressful than transporting fish by hand because it minimizes human contact and gets them back into water faster.

A biologist feeds a fish into the vacuum tube. Click to enlarge (Courtesy of HCN)

Whooshh is now working with state, federal and tribal groups to implement and improve the system. Though it’s still in its early stages, Whooshh has high hopes for the idea. Here’s Todd Deligan, who runs Whooshh’s fish-transport program:

“The ultimate goal would be to get fish to places they haven’t been able to access, like the upper Columbia… But that’s a very long-term goal. We’re not going over Grand Coulee (Dam) tomorrow, that’s for sure.”

Read the original story from HCN here. To learn more about the salmon of the Pacific Northwest, check out this awesome special from National Geographic: “Salmon: Running the Gauntlet”.

Did Something Just Eat A Great White Skark Off The Coast Of Australia? (Video)

The discovery came from Australia’s first ever large-scale tagging and tracking program for great white sharks.  Lead by filmmaker Dave Riggs and a film crew, the team successfully tagged a 9-foot bluechip specimen and named her “Shark Alpha”.

Four months later the tag was mysteriously found washed up on the beach. When the data was collected from the tracker, Riggs was stunned. According to Yahoo.com,

“Alpha had plunged straight down the side of the continental shelf, more than 1,500 feet deep. While the temperature of ocean water drops considerably in deep water, the tag itself actually heated up, from 46 degrees Fahrenheit to 78 degrees. That means the tag had to have been inside the belly of another animal. Alpha had been attacked, and bested, but by what?”

The story is chronicled in the upcoming Smithsonian documentary, “Hunt for the Super Predator.”  which can be viewed below.

Of course after the story surfaced on the internet, theorists from all over gave their best guesses as to what could’ve happened- some based in fact (like an Orca or giant squid), others in fantasy (like the Kraken).

So what did eat this 9-foot great white? Well, the most likely answer is that Alpha was eaten by another member of her own species, or as the scientists called it, a “colossal cannibal great white shark”.

This wouldn’t be too surprising: the average adult great white is between 13-16 feet in length, with some monsters growing up to 20+ feet. Great whites are also known to be aggressively territorial, and a bleeding, injured shark, even a great white, wouldn’t last long in waters full of other sharks

No matter what actually happened to this 9-foot great white, I don’t think that I’ll be swimming in Australia anytime soon…

Swim With Fluorescent Sharks, Stingrays and More in the Solomon Islands (Video)

Bioluminescence is the ability of an organism to create light using its internal chemicals (fireflies are a good example). It is seen in many small creatures living in the dark depths of the deep sea, but it wasn’t until recently that researchers realized just how many bioluminescent marine species there are.

These researchers were originally researching bioluminescent coral, but ended up discovering 180 species of fish that also exhibited this exceptional attribute.

For more information and photos, check out this page from National Geographic.

 

 

Insane GoPro Footage Shows You What It’s Like to be Chased by a Hungry Shark (Video)

This footage was captured off the coast of Ocean City, Maryland in July 2013. Makos (the species of shark in the video) are the fastest sharks in the world, reaching speeds up to 60mph in short bursts. The corny “Jaws” theme in the background was not my idea by the way…