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Sunday, February 21, 2016

around the world report

Jonathan Bird's Blue World: Kelp Forests


Coming up next on Jonathan Bird's Blue World, the kelp forests of southern California. Hi, I'm Jonathan Bird and welcome to my world!This is Harold Parker State Forest in Massachusetts.  It looks like a typical forest.  But not allforests are the same!I’m heading to Catalina Island, off the coast of California, to explore another kindof forest. The Forests here are underwater!Getting here from the mainland is as easy as boarding a ferry.  Ninety minutes later,we arrive in Avalon, one of only two settlements on Catalina Island. I head on over to Catalina Scuba Luv dive shop to pick up some scuba tanks, and then,it’s off to Casino Point for a shore dive. Casino point is a beautiful spot just outside the harbor.  It’s also a marine reserve,so no fishing is allowed. I waste no time, and start suiting up to explore this dive site that has such a great reputation. Casino Point is set up as a “Dive Park” with a protected area just for divers, safefrom boat traffic. And look, a staircase right into the water!I walk down the steps and descend into the Pacific Ocean. Immediately, I am greeted by blue water, excellent visibility, and lots of kelp!And now I know why they call these places kelp forests! The kelp grows up from the seafloor as tall as trees.  I really do feel like I’m in a forest!Kelp is a kind of marine algae that can take many forms.  The kelp forests around CatalinaIsland are formed by Giant Kelp, which can reach the height of a 14 story building inonly a single growing season because it can grow 2 feet a day! It’s one of the fastestgrowing organisms on Earth!Looking down at it from above, I see what an eagle might see, flying over the treesin a forest. But unlike trees on land, the kelp doesn’t have a rigid trunk to hold it up.  In fact,the kelp is quite floppy.  So how does it stay vertical?At the base of each leaf, called a frond, is a pneumatocyst—basically a little gasbladder.  Each one of these pneumatocysts provides buoyancy, so the kelp floats. Down on the sea floor is something called a holdfast.  Basically it’s like a set ofroots that hold onto the rocks.  Kelp needs something heavy on which to attach itself—itcan’t grow in a sandy sea floor. So between the pneumatocysts keeping it afloat and the holdfast keeping it from floatingaway, the kelp hangs vertically in the water. Kelp is really important in this ecosystem because it’s a great place to hide.  AndI don’t mean for divers!This is a great habitat for fish to seek refuge from predators, so the kelp forest is filledwith thousands of fish. The most famous kelp forest resident in Southern California is most certainly this damselfish—theGaribaldi. Garibaldis are hard to miss—no other fish in the kelp forest is so brightly colored. Although Garibaldis become aggressive when they are guarding a nest of eggs, the restof the time, they don’t seem bothered by divers much.  In fact, this one seems positivelycurious. I find it hard to film the kelp because every time I settle down to get a shot, a Garibaldipokes its head in to see what I’m up to.  So I film the curious fish for a few minutes,only to discover a whole bunch of other fish watching the show. It seems I have become quite popular down here.  Because lots of divers come to thissite, these Kelp Bass are not afraid.  They must know that there is no fishing allowedin this sanctuary.  They pose confidently for my camera!Nearby I also find a Turban Snail.  These snails move up and down the stipe of the kelp, munchingaway on the algae. All this munching is making me hungry, so as my tank gets low, I turn around and headback to the steps.  Time for some lunch!The following morning, I board the Catalina Scuba Luv boat King Neptune.  We’re headingout to visit a different kelp site, in hopes of finding some additional residents of thekelp forest!We leave Avalon Harbor under a beautiful blue sky. Only half an hour from the dock, I prepare to dive.  The water is in the mid-60s so a7mm wetsuit will keep me nice and warm. I hop into the water from the dive boat’s convenient submerged swim step, and Juliahands me my camera. I descend into the blue, and soon enter another mysterious kelp forest. I head out deeper, to a sandy slope where there isn’t much substrate for the kelp. At a depth of 90 feet, we discover a rare resident of the kelp forest—a Torpedo ray!I move a piece of kelp so I can get in close for a shot.  The ray is not afraid of me, becauseshe has a powerful means of defense—electricity! This animal generates an electrical chargeof nearly 50 volts that it can use to zap predators, or its prey. The Torpedo Ray has a curious looking tail, unlike most other rays.  I want to see herswim so I can film the tail—so I give her a little tickle. The ray immediately turns around and faces off against my camera.  I wasn’t expectingsuch an aggressive reaction, so I keep my camera between the two of us and we stareeach other down! I’m not making any sudden moves and neither is she. But as Cameraman Todd moves in closer for a shot and inadvertently closes her avenuefor escape, the Torpedo ray panics and attacks my camera, pulsing the muscles in her abdomenthat create electricity!Then, as quickly as it began, she calls off the attack and swims away.  I follow alongbehind and now I can see how she swishes her tail back and forth to swim like her relativethe shark--much different from how other rays swim. What a way to end an incredible couple of days diving Catalina Island! These beautifulforests of kelp, and their colorful inhabitants, truly are one of the many wonders of the BlueWorld.

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