Sharks’ Social Behavior: Solitary or Sociable?

Someone shouts “Shark!” What do you expect to see? For most of us, we may picture the solo great white shark looming ominously below the kicking legs of innocent beachgoers. Or the dorsal fin of one massive tiger shark as it peaks out above a swelling wave. But would we ever picture sharks huddled together in pods like dolphins, or in schools like tuna?

“The general feeling is that sharks are robots — that they’re antisocial and they go around munching and killing things,” Dr. Brown said. “Nobody knows about the social lives of sharks because it’s notoriously hard to track them.” -Dr. Culum Brown, an assistant professor at the Behavior, Ecology and Evolution of Fishes Laboratory at Macquarie

Though it may be evidenced that many larger sharks tend to “fly solo,” is this true of all sharks? Are sharks capable of social interactions like humans? Do sharks exhibit a longing for companionship? How can sharks’ ability or inability to interact socially affect our perception of them? Today we explore these questions.

Researchers in Australia have been studying the social interactions of Port Jackson sharks for several years now. Dr. Culum Brown and his colleagues used many different tracking devices to tag and released Port Jackson sharks. One example would be “Passive integrated transponders, or PIT, tags, slightly larger than a grain of rice, hold electronics that allow them to act as lifelong bar codes that can be detected and read without the animal having to be recaptured.” Dr. Brown and his team have been tracking Port Jackson sharks to explore their interactions with each other. Do they congregate in a specific area? Do their tracking patterns regularly cross paths in one habitat?

The researchers noticed that Port Jackson sharks often congregated together. To determine whether this behavior was due to a preferred environment or a tendency to be social, Dr. Brown simulated the Port Jackson’s natural environment. When placed in an aquarium habitat, “instead of being spread out around the pool, they are always together,” Dr. Brown said. “We’ve seen this in the wild, too, but here, there’s no reason they’d be attracted to anything in the shelter, because it’s all artificial.”

Port Jacksons’ social interactions can indeed help conservation efforts. If people can associate with sharks and recognize familiar behaviors, we may be more open to seeing them as fascinating creatures.

“The fear of sharks is an irrational one,” he said. “It’s hard to get over an irrational fear. But we’re trying to teach people that sharks aren’t mindless killing machines, that sharks are interesting and do interesting things. The reality is that humans kill millions of sharks every year. Most sharks are under threat from us, not the other way around.” -Dr. Brown

**All quotes from this post come from recent article in the New York Times, “Studying Sharks’ Social Lives to Expose Their Friendly Side”

Resolve to Solve

So it’s 2016. Can’t think of a New Year’s Resolution? Have one but you’re looking for more? Already broke yours and looking for a new one?

Ditch the diet resolution this year, and resolve to help solve current environmental management issues! With your help, leading scientists and activists can find the means to effectively deal with environmental crises. And, in fact, you are needed MOST in 2016. As Sylvia Earle says,

“The next five years may be the most critically important of the next 10,000+ years—the best chance our species will have to protect what remains of the natural systems that give us life.”
– Dr. Sylvia Earle

So act now! Here’s a few simple ways to make a difference:

  1. Pledge to Eat SustainablyDownload the Monterey Bay Aquarium’s Seafood Watch App to become a sustainable eater today. The next time you’re debating whether to get the Tuna Tartare or Mahi Mahi, type in your choices to see if your dish is a good choice, or something that you should be avoiding. This is one of the easiest ways to think before you eat!

2. Ditch the Plastic!

Make a promise to yourself to limit plastic in your life. Think about using reusable water bottles or shopping bags in 2016. (I have been plastic water bottle free for over three years now! You can too.)

3. Calling All Divers: Dive Against Debris

Work with Project Aware to clean up trash that pollutes our oceans and endangers marine life. Pick a dive near you and jump in! Or you can donate to Project Aware to facilitate the actions of other Dive Against Debris divers

4. Take Project Aware’s Ocean Pledge

Pledge to follow Project Aware’s 10 tips for divers to help protect the ocean. One tip is to shrink your carbon footprint. Can you guess what the others are?

5. Open Ended: Use your unique talents to help fight for the ocean

“Look in the mirror, consider your talents, and think about how you might use them to make a difference. Some have artistic skills, others are good with numbers or have a way with words. Everyone has power to make a difference as an individual, or by joining the company of others who share a common goal. The key is in knowing that what you do matters, including doing nothing!” – Dr. Sylvia Earle