Thursday, February 13, 2014

Shark Week (or why great white sharks in Maine = supporting community radio) Part 2

Note: This program first aired on February 15, 2014.

Because its Funathon, and because this is community radio, we’re trying something that has proven to be really successful for the Discovery Channel. Today, on the World Around Us, we wrap up Shark Week!

When we talk about sharks in New England, the big question on everyone’s mind is: are they here? And the answer is, of course, oh yes. Once source I looked at reports 13 species of shark to be found in the waters of the Gulf of Maine, and Henry Bigelow’s seminal work Fishes of the Gulf of Maine lists 23, though many of those are included as single reports, or from south of Cape Cod. Along with those 13 to 23 species of shark, we will also commonly find at least five species of skates and one chimaera. Most of us are familiar with the ubiquitous spiny dog fish, a relatively small shark that preys upon fish, much to the chagrin of fishers throughout the Gulf. But there are many other well known sharks that frequent these waters, makos, blues, threshers porbeagles, and the infamous white shark.

When people ask about sharks in the Gulf of Maine, the white shark is really what they are asking about. White sharks have long been known as “man eaters” but it was the 1975 blockbuster Jaws that cemented the public’s perception of what this shark is all about, though it should be noted that famed naturalist Henry David Thoreau also wrote about a white shark attack in his 1855 work “Cape Cod”. White sharks are on the large end of the shark size range, growing to well over 20 feet. My house is 20 feet wide, which makes it easy, and terrifying to visualize the length of these animals. Sharks that large can easily weigh thousands of pounds, the largest seemingly reliable white shark report weighed in at over 7000 pounds. For reference, your average Subaru Outback, the state car of Maine, weighs in at just about 3400 lbs.

The general impression among those who are paying attention to such things is that there are more and more white sharks around in recent years than there used to be. Sea surface temperatures may have warmed a bit, but most of us would still consider them to be pretty cold even in the summer, and white sharks are what we would call “warm blooded” in that they can control their internal body temperature to be above that of the surrounding environment. No, its not water temperature that is bringing the big hungry sharks back, it is the all you can eat buffet that has been restocked in the past 40 years by none other than the federal government. White sharks are an apex predator in the ocean, and marine mammals, especially seals, are their favorite food. It used to be, back in the olden days, that fishermen could kill seals, who they thought were stealing their bait and eating the target fish species, or in the rare case of Andre the seal, fishermen occasionally kept seals as pets. As a result seal populations in the Gulf of Maine were relatively low. The harbor seals we see every where today, and the gray seals we see off shore were not a common sight. But since 1972, when the Marine Mammal Protection Act was passed, these seals, along with all other marine mammals, have been protected, which has allowed their numbers to rebound quite successfully. Fast forward 40 years. There are lots of seals here, white sharks eat seals, the math is really quite simple.

If it makes you feel better, keep a few of things in mind: first, you can go online and see if any tagged sharks have called in their locations, just remember, only 38 White sharks are outfitted with these tracking tags. Secondly, white sharks reportedly don’t strike with an initial killing bite. The first bite is said to be an exploratory nibble, the sharks are testing to see if their intended prey is encased in thick layer of delicious sealy blubber, which is yet another argument for staying in shape. Third, and probably most important, intact ecosystems, ones that include their apex predators, are more robust and resilient, and the presence of white sharks, or any sharks, in the ocean should simply serve to remind us that the ocean is a wilderness, not a suburb or a shopping mall. And it is in the wilderness that we humans are reminded of our place in the great order, not on the tippy top pinnacle of the pyramid, but somewhere in the web, connected in all directions to all the organisms around us.

That finishes the Shark Week experiment. If you liked it, please call 1800 643 6273 and pledge your support to this radio station. Because they let me come on the air and talk about whatever cool nature thing is grabbing my interest, because you can go on line and listen to this show, and any show I have done again and again or down load them to your digital device of choice, because this community, sharks and all, would be a sad and lonely place without WERU. So give us a call and tell us you liked Shark Week, if you did, and help support this kind of programming far into the future. Thanks!


From an enthusiastic New Englander, with lots of good photos:

Follow tagged sharks (but remember, they aren’t all tagged):

The Marine Mammal Protection Act:

An amazing resource, Bigelow’s Fishes of the Gulf of Maine, online and open access: