I may have mentioned in some other thread that a buddy of mine lost his bilge pump when he went out to the reef on our coldest day this winter in winds 15-20 knots in his flats skiff to catch ballyhoo for a big sailfish tournament. I declined to go due to the cold (he was staying at my place).
I got a call about 2 hours later from him asking me to turn the shower on hot as it would go. He was a minute from the house on his way back.
As always, he checked out his bilge pump before launch, and it was humming like always, so he headed out. It didn't pump anything, of course, since his bilge was dry.
When he got to the reef and anchored down, he turned on his pump because he took a couple waves over the bow and his scuppers feed into his bilge. It was humming fine (same as at the launch ramp), but was not pumping water. So he pulled anchor and headed immediately in, taking spray and water the whole way back into a freezing 20 knot wind. He forgot that he had loaned his spare pump to his cousin.
The problem was a bug - some kind of leaf roller that had rolled up a nest in his bilge pump hose just inside the fitting.
I used to have to connect all my air hose ends together in Phoenix because of those things. They build a nest out of rolled leaves that is put together tighter than a cigar, and stuffed in so tight that it is completely waterproof. We got it out with an air compressor by disconnecting the hose from the pump inside of the bilge once we figured out that the hose was clogged. It went flying out into the parking lot - a regular cigar cannon.
Aside from a spare bilge pump with its own hose - here is what I have taken to doing since that happened to him this winter. It is something I can easily see and remove.
I alsos tape my tank vent shut ever since a mud dauber had sealed it off with a nest, and it took me a while to figure out why I wasn't getting gas fast enough. Not a big deal there because you can crack open the fill cap and gas will flow to the engine again, but who wants mud in the gas tank?
Not quite entomology, but bug-related.
Just something to remember.