ALERT BUT NOT ALARMED?

The noise was quite insistent, and very disturbing.  It sounded like kindling burning, or a camp fire crackling.  In the quiet of the night on our mooring in the Clarence River, it was very unwelcome. 

Lying in bed, I skimmed through alternate explanations. Top of mind was a short in the electrical wiring with its attendant fire hazard and power failure. Or, perhaps some sort of chemical reaction on board?  Or a weird engine going past? 

Alert and alarmed, I morphed into Sherlock Holmes mode. The noise was very diffuse and pervasive. It was really loud in the engine room, and in the head, moderate in all other cabins. It disappeared on deck. During my futile midnight search, it occurred to me that the sound was reminiscent of the noise you hear when scuba diving on a reef where crayfish are present.  In the end, that night, I decided that it was crabs roosting on the hull (I was tired) and went back to bed. Elementary my dear Watson.

Next day, I hit the net. Thank God for Google.  What I found is that yachties from all over the world have been alert and seriously alarmed when first they meet this noise.  Many report practically dismantling their yachts on the hunt for the noise that is described variously as frying bacon, crackling, or rice bubble pop. Most, like me have been intent on assessing whether the noise is vessel threatening, a risk to life or limb, or just the normal massive drain to the pocket. 

Various theories about the noise have been put forward. My favourites are that cockroaches or mice plagues have infested the boat, that the anti-foul has got active and is noisily eating slime, that electrolysis is devouring the hull, or, more likely, all of these simultaneously. The consensus explanation is that the tiny shrimp krill are snapping their jaws as they eat and the yacht hull acts as a huge transponder, magnifying the sound.  If it is these tiny shrimp, they are most likely eating the marine growth that accretes to the hull.  So yachties can until further notice consider it a comforting sound, much like campers do the crackle of a camp fire.

But stay alert.  Be alarmed. It’s good for you.

I want a fridge magnet.