It’s Shark Week for Us Too!

The National Marine Life Center is celebrating a summer holiday as well, Shark Week! This week’s educational programs, Fins & Flippers and Marine Animal Medical Mystery, are dedicated Sharks and Rays. Come join us Tuesday and Thursday at 10 am for Fins & Flippers Club and Wednesday at 10 am for Marine Animal Medical Mystery! I can promise no shark bites as we learn about the ocean’s most feared predators. However, hopefully we can take a bite out of this apex predator’s negative reputation. Let’s sort some shark myths from reality!

Recent sightings of sharks along Chatham beaches may bring scenes from Jaws to mind. While it is the same species of shark spotted along Chatham as in the movie, these are true great white sharks and not Hollywood hyperboles. It is true that this shark can detect a single drop of blood in 25 gallons of water, which can be up to 3 miles away. What isn’t true is that sharks crave the taste of human blood. Most human attacks from great whites are what’s called “sample biting,” when the shark will let go of the person after biting realizing that human meat is not what it wants to eat. Often attacks are because of “mistaken identity” when sharks mistakes surfers or swimmers for prey. Because shark attacks are reality, you should be familiar with precautions to avoid one. Just remember what not to do with your “ABCDE’s”!

1. Alone. Do not swim alone, and don’t go too far from shore. Often sharks attack individuals and being alone can decrease your chance of getting lifesaving assistance.
2. Blood. Do not go in the water if you are bleeding or get injured while swimming.
3. Contrast. Sharks are attracted to contrast, like shiny jewelry which can be mistaken as fish scales or high-contrast clothing which can be mistaken for counter-shading like pattern of many prey items.
4. Dusk and Dawn. Avoid swimming at dusk, dawn, and night which are active times for sharks. Sharks can see well in low visibility conditions for people.
5. Eat. Do not swim where animals which sharks eat are. Avoid areas full of bait fish, fishing activity, seals and sea lions. Dolphins and sea birds circling may also be a sign sharks feeding nearby.

Always pay attention to local beach warnings and shark sightings as well. Respecting these animals as a predator is the first step to understanding their true nature. These animals are built to eat seals, sea lions, and fish; not to eat people. Great white sharks look for prey with the highest yield of energy. Sharks are about 85% muscle, while humans are only 40%; and it takes a lot to maintain a shark’s body. Seals and sea lions are the perfect meal because of their blubber and fat which yield a lot of energy. To white sharks, people are a skinny meal not worth the energy to consume. In order to identify prey, white sharks rely on visual cues like the body outline and color. Great white sharks often attack from below, swimming vertically at the prey, and mortally wounding it by force or biting. This behavior, which also includes breaching, is quite popular in South Africa while the sharks hunt fur seals.

Sharks go where the food goes, and the sharks spotted along Chatham were around an area populated with seals. With so many seal sightings this summer, it’s no wonder the sharks are nearby. Even if you don’t see a shark in the ocean this summer, you can have your own shark experience at the National Marine Life Center! Join us for our Fins & Flippers and Marine Animal Medical Mystery. Discover “mermaid’s purses” in our Beachcombers’ Table. These “mermaid’s purses” are egg cases for different species of sharks and rays. Stop by and learn how you can help with ocean conservation to protect ocean treasures like the Great White Shark.

Posted by Alexa S.
Alexa is a Summer, 2011 Intern at the National Marine Life Center.