Giant Australian Cuttlefish! (They're almost as big as my kids!)

Coming up, Jonathan and the family head down under, looking for mating cuttlefish. Do they cuddle? Welcome to Jonathan Bird's Blue World! The Australian Giant Cuttlefish is the largest cuttlefish in the world, reaching a total length of nearly a meter. Using color-changing skin cells called chromatophores, this mysterious master of camouflage can be very hard to see. But this curious cephalopod may just come over to see you! Between May and August, tens of thousands of these cuttlefish aggregate to spawn in the waters of South Australia. One particular place, Point Lowley, near the city of Wyala, is known around the world as the place to see Australian Giant Cuttlefish. It's summer vacation for our kids, so Christine and I are taking them on an Australian adventure to meet the cuttlefish. The kids have been on dive trips before, but this is their first trip all the way to Australia, with two 12-hour flights and a stop in Dubai. At last we make it to Adelaide, South Australia, with all our luggage, ready for an adventure. We load the minivan and then embark on a 6 hour drive to the beautiful and remote town of Point Lowley, located on a peninsula with a lighthouse at the end. We drive down the peninsula looking for a famous shore diving site. Well, we made it to Point Lowley. Supposedly there is a dive site around here with a bunch of cuttlefish. I'm just not sure exactly how we find it. But before we go diving, we need to find our home for the next few days. We rented a house on the beach, about a mile from the dive site. And what a spot! I have to say, this is an awesome little dive prep area! And this is the best part of the house, because look at this view man! As the sun sets over the lighthouse, we plan for our dive with the cuttlefish tomorrow. Alright you guys ready? Thrilled! Let's get my boots on! It's going to be awesome! Yeah! You are about to see the world's largest known cuttlefish aggregation. Wow! I know! Alright, let's do it! Let's go! We hop in the van for the short ride down the street to the dive site. Christine and I are ready for the 12 degrees Celsius water with our drysuit undergarments ready to go. A dirt road leads down to the water. I've never seen such nice provisions for divers. A pavilion for changing and rinsing gear, plus a walkway right down to the water. It doesn't get any better than this. So we waste no time getting suited up. Summer at home is winter in Australia, and the brisk wind here comes off Antarctica. It's sunny, but it's not warm. Elise and Liam are in wetsuits, so they are not going to last long in this water before they are cold. But they came all the way to Australia to see some cuttlefish, so they are ready. We walk down into waist-deep water and put on our fins. Then we only have to swim out a little ways to get into water deep enough to submerge. We start seeing cuttlefish immediately. In fact, it turns out that most of them are in water no more than 4 meters deep. You really don't even need dive gear. You could see them with a snorkel. We have definitely crashed the party. Two big males are engaged in a dance-off. Each one is trying to look more colorful and flamboyant than the other. These non-violent battles are all about impressing the females and intimidating rival males. They keep an eye on us, but mostly they keep an eye on each other, trying to see who has the better colors. Color-changing cells in the cuttlefish's skin are normally used for camouflage. But during the mating season, they are used like a neon sign to advertise awesomeness. Sometimes tempers flare and the males take a swing at each other. But eventually, if he is lucky and persistent, a male attracts the attention of a female. The females are easy to identify because they are much smaller than the males. Once he has a willing female partner, the male must still fend off other males looking to try stealing her away. Later the male and female will mate. But even then, there is no privacy and the pair still has to keep an eye out for other males on the prowl. Sometimes the big males get so preoccupied with showing off that they fail to notice smaller males sneaking in behind their backs to mate with the females. These smaller males, aptly called sneakers, are often quite successful. Eventually the female deposits her fertilized eggs in deep holes under rocks, where they will be safe from at least some predators. They will hatch in three to five months. Sadly, because the cuttlefish do not eat at all during the spawning season, they get weaker and weaker, slowly metabolizing their own bodies to stay alive. Once the mating is done and the eggs are laid, all the cuttlefish die. Although the cuttlefish spawning is still going strong, the kids are getting cold, so it's time to head out of the water. So here's the thing. Cuttlefish. First of all, they are not fish. And second of all, they don't cuddle. So I'm not quite sure. I guess they cuddle each other. Back at the house, I find a cuttlebone on the beach. Most cephalopods don't have any bones, but the cuttlefish is different. The cuttlefish is the only cephalopod that does have a hard bony structure in its body, this thing, called a cuttlebone. But unlike a normal bone, it's not heavy. This thing is light as a feather because this calcium bone-like structure is actually filled with micro air bubbles. It's sort of like a piece of foam. And what it does is it provides buoyancy for the cuttlefish. This thing floats like a cork, and it helps them maintain neutral buoyancy without having a swim bladder like a fish. Since I'm finding cuttlebones on the beach behind our house, that gets me thinking. So about a half a mile up the coast is the famous cuttlefish dive site, where the cuttlefish are supposedly doing their thing. But we noticed, way down the beach in front of the house that we rented, we noticed that there are cuttlefish bones, cuttlebones, everywhere. Which means there's probably cuttlefish right out there. What I want to know is, are they reproducing all along this whole beach, or are they really only down there for some special reason? So today I'm going to do a dive and see what I find. I suit up for a shore dive to find out if there are any cuttlefish here. The wind has come up, it will be a little surgy underwater, but I don't need to go far. They are either here or they aren't. I submerge as soon as I get deep enough to swim, and kick out over a rocky bottom. So far, there's nothing to see but rocks. When I reach a depth of about 3 meters, I enter a zone of algae and rope sponges. So far, no cuttlefish. Wait a minute, what's that? There's one! And another! This place is crawling with them! They like the depths around 10 feet deep, just like at the other dive site. And there's definitely nothing magical about that particular site. This whole bay is filled with cuttlefish. They are mating, and depositing eggs. After a few minutes, I head back to the beach and carefully trudge out of the ocean, trying not to trip. My mission a success! The Point Lowly region in South Australia is a wonder of nature. It's the only place in the world where large numbers of giant Australian cuttlefish are known to aggregate and spawn. For someone traveling from the other side of the world, it's a long trip. But it's worth it to witness such an amazing spectacle of the Blue World! Hey Everyone! Thanks for watching our latest episode all the way to the end! You're crazy if you don't subscribe! Hit that subscribe button now so you won't miss our next episode! And check out our merch link in the description for some Blue World swag!