Sharks with cameras attached to their fins reveal surprising behavior

Instruments strapped onto – and in some cases swallowed by – sharks are shedding new light on how sharks swim, eat, live, and interact with other marine life.

|
Mark Royer, University of Hawaii
Scientists attach a combined sensor and video recorder to a shark.

Thanks to some innovative technology, details about the lives of the most mysterious underwater creatures are now coming to the surface.

Apparently, researchers have found that different species of sharks congregate together, challenging the widely held image of sharks keeping to themselves, or at least sticking with their own kind, says Kim Holland, a researcher at the Hawaiʻi Institute of Marine Biology, who was involved with the study.

Scientists also learned that sharks frequently use powered swimming, instead of gliding, to move through ocean waters.  

To learn about the sharks' lives, researchers from the Hawaiʻi Institute of Marine Biology and the University of Tokyo equipped several sharks from five different species with video cameras and instrument packages. These packages are like "flight data recorders," says Carl Meyer, an assistant researcher at the Hawaii Institute of Marine Biology at the University of Hawaii at Manoa. The instruments recorded details such as the speed, temperature, and body orientation of sharks.

The packages were strapped to their pectoral fins, and were set to detach from the animals after one week, Dr. Meyer says. The packages then floated to the surface and sent out radio signals that allowed researchers to find them. 

The method, says Meyer, gave them a "shark's eye" view of how the fish formed into and disbanded schools. This study was carried out among wild sharks.

But to learn about the food habits of sharks, researchers studied captive sharks, who swallowed small computers fitted with various sensors that are 2.5 inches long; an inch wide and half an inch thick – roughly the size of a lighter, says Dr. Holland.

The researchers got the sharks to ingest these computerized tags by placing them into the body cavities of smaller fish that they fed to the sharks. The sharks couldn't actually digest the tags, so they regurgitated them after a while. While the tags were in the sharks' stomachs, they measured the electrical conductivity of the stomachs' contents.

As of now, it is easy for the scientists to look within the pen and locate the tags. The researchers say that they hope to develop a tag that can be monitored via satellite.

Through this study, scientists are trying to get "a much deeper understanding of sharks’ ecological role in the ocean, which is important to the health of the ocean and, by extension, to our own well-being," said Meyer in a press release. 

You've read  of  free articles. Subscribe to continue.
Real news can be honest, hopeful, credible, constructive.
What is the Monitor difference? Tackling the tough headlines – with humanity. Listening to sources – with respect. Seeing the story that others are missing by reporting what so often gets overlooked: the values that connect us. That’s Monitor reporting – news that changes how you see the world.

Dear Reader,

About a year ago, I happened upon this statement about the Monitor in the Harvard Business Review – under the charming heading of “do things that don’t interest you”:

“Many things that end up” being meaningful, writes social scientist Joseph Grenny, “have come from conference workshops, articles, or online videos that began as a chore and ended with an insight. My work in Kenya, for example, was heavily influenced by a Christian Science Monitor article I had forced myself to read 10 years earlier. Sometimes, we call things ‘boring’ simply because they lie outside the box we are currently in.”

If you were to come up with a punchline to a joke about the Monitor, that would probably be it. We’re seen as being global, fair, insightful, and perhaps a bit too earnest. We’re the bran muffin of journalism.

But you know what? We change lives. And I’m going to argue that we change lives precisely because we force open that too-small box that most human beings think they live in.

The Monitor is a peculiar little publication that’s hard for the world to figure out. We’re run by a church, but we’re not only for church members and we’re not about converting people. We’re known as being fair even as the world becomes as polarized as at any time since the newspaper’s founding in 1908.

We have a mission beyond circulation, we want to bridge divides. We’re about kicking down the door of thought everywhere and saying, “You are bigger and more capable than you realize. And we can prove it.”

If you’re looking for bran muffin journalism, you can subscribe to the Monitor for $15. You’ll get the Monitor Weekly magazine, the Monitor Daily email, and unlimited access to CSMonitor.com.

QR Code to Sharks with cameras attached to their fins reveal surprising behavior
Read this article in
https://www.csmonitor.com/Science/2014/0228/Sharks-with-cameras-attached-to-their-fins-reveal-surprising-behavior
QR Code to Subscription page
Start your subscription today
https://www.csmonitor.com/subscribe