The Elusive Hull Snacker
14 January 2011 | Mazatlan
There are many strange and mysterious things that live in the sea. There are also many things, unseen things, that go bump in the night, so to speak. This story is about both.
We first heard about Hull Snackers from a cruiser we met on Catalina Island. "You will hear them," he said "when you are just about to go to sleep you will hear them scratching and gnawing at your hull, like rodents from the deep." We laughed. It sounded so improbable at the time.
Our first experience with Snackers was in San Diego only a week later. There is something about shallow lagoons fitted with docks that seem to attract Snackers. Maybe it's the boats themselves within the lagoons that are the enticement but I don't think so. As I recall it was late and we were very tired from a long passage that started that day at 4:00 a.m. We were lying in our bed, just about to go to sleep. It was very quiet at first. Then we heard a high-pitched popping sound followed by a series of scratching noises. Then there were a few sharp crackles followed by more scratches and pops. It was hard to tell where the sounds were coming from. I jumped out of bed and moved to the saloon area. More of the same. The scratchy noises were coming from nowhere and from everywhere. It took a while but we slowly came to the realization that the noises were coming through the hull - from the outside. Something was out there trying to get in. Or maybe something was having a midnight snack on the bottom of the boat. Yes indeed folks, we were experiencing our first attack of Snackers!
We were not alone in that regard. Our friend, Mark on s/v Merkava, also in San Diego Harbor, thought he had mice on board. He heard the scratching sounds late one night and tore the boat apart for hours looking for the furry invaders. Of course his search was fruitless and after several nights he gave up. When we told him about our similar experience and our conclusion they were sea creatures nibbling on the outside of the hull he was very relieved. No mice - just Hull Snackers!
Every cruiser has a theory on what they are. One fellow told us they were baby squid eating algae off the bottom of the boat. Their little beaks make the scratchy sound. Another said they were brine shrimp and the noise was their tiny claws picking tidbits off the hull. Personally, I think they are very aggressive barnacles looking for a home. They throw themselves against the hull, hoping to latch on. They are repelled by the very foul anti-fouling paint, back off and the try again. This goes on all night because barnacles have very small brains. Who knows?
The sounds that Snackers produce varies from one harbor to another. In Mazatlan, at Marina El Cid, they were especially active. Imagine a big bowl of Rice Crispies. Now fill the bowl with milk and put your ear very, very close. Hear the snap, crackle, pop? Now record the sound and play it back at about 2 or 3 times faster than normal speed. And loop it so it plays all night! This might give you the idea. They were so noisy it sounded like the boat had a static electrical charge. One night, determined to see what they looked like, I got out of bed and went on the dock with scoop fitted with a fine mesh screen, purchased specifically to try to capture Snackers. Alas, despite numerous passes along the hull my special scoop came up empty. They are elusive!
So the exact nature of Nocturnal Hull Snackers remains a mystery. Maybe one night, when the water gets a little warmer, I'll put on my scuba gear, hide below the boat with an underwater flashlight and lay in wait for some pesky Snackers to come to dine or do whatever they are doing. If I solve the mystery you'll read about here first on the Sarah Jean II blog!