Tag Archives: Cuttlefish

Humans being loud under water, Cuttlefish

Last June (and May and July and part of August) we had a lot of precipitation in Minnesota. This caused lake levels to rise modestly. One lake, which is large enough to have meaningful waves, has older settlement along it so lots of cabins, boat houses, and such are right on the shoreline. With the lake level up, waves threatened the material possessions of rich white people, so naturally something had to be done. A No-Wake Rule was put into effect.

A No-Wake Rule means the oversized fishing boats and smallish cabin cruisers that normally ply this large exurban lake need to all go at 5 m.p.h. or less, and forget about wake boarding, water skiing, and all those other fast, wake churning activities. The result? A lot of butt hurt, a near First World depression setting in in the Twin Cities wester suburbs. Somebody took away our boy toys!

But then, somebody went fishing. It isn’t a great fishing lake. It is mainly a go-fast lake. In fact, it is on this particular lake, I believe (with no evidence I quickly add) the method of fast-trolling for muskies was invented. This is a way to “go fishing” and go fast at the same time. You drag the lure behind you as fast as your boat will go. It is said you can catch muskies this way. To my knowledge it has never happened. Just more boy toy.

Anyway, somebody went fishing on the No Wake Lake, and guess what happened? They caught a boat load of fish! Literally! Then their friends went out fishing, and they caught a boat load of fish too! Pretty soon all the fisherpersons who had access discovered that when you don’t drive giant boats back and froth across the lake at high speed all day, the fish feed. When you do, they hunker down, feed infrequently, and grow slowly.

Now, I’m not going to vouch for this relationship just yet, but it makes intuitive sense. In my own experience, quiet places are where you catch fish. If I’m fishing up at the lake, once the boats start driving around skiing (say on a fourth of july weekend) I might as well reel it in and go get a beer, because that’s the end of the fishing. I’m pretty sure my best fishing has been on Wednesday and Thursday, before the startup of the loud and noisy weekend. And that’s on a quietish part of a relatively quiet lake.

The only reason I’m mentioning this now is because I came across this story from my Science News Roundup:

The blare of human noise causes birds to pipe down and frogs to breed less frequently. Now, scientists have found a humanmade sound that has a far more colorful effect: The boom of a ship’s engine makes common cuttlefish (Sepia officinalis) change the complex swirls of skin hues, stripes, and spots that they use for camouflage and communication. …when researchers placed a loudspeaker near cuttlefish tanks and played the sound of an underwater engine, the animals swam more and changed colors more often. They also raised their first pair of arms, which are used to sense water movements, more frequently…The sounds of crashing surf had no effect, providing the first evidence that engine noise may stress the animals out.

The original story is here, in American Naturalist.

I would love to see a large number of large lakes shut down for boating. No motors. Eventually, of course, there will be no gas powered motors, with the shut down of fossil fuels. I promise you, when we start using quiet electric boats for fishing, the fishing will get better.