The Adventure of the Malfunctioning Modem

A different kind of pesky critter, and a different kind of field. This phenomenon was a topic of humorous conversation in the Bell Labs Undersea Light community in the mid-eighties.
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From the Wall Street Journal, 26-June-86
By Bob Davis
Staff Reporter of The Wall Street Journal
Just when American Telephone & Telegraph Co. thought it was safe to go into the water, sharks began dining on its newest undersea
telephone-communications cable.
It seems the sharks just can't get enough of AT&T experimental underwater fiber-optic telephone cable near the Canary Islands. They
munch on its plastic covering, gnaw on its electrical innards and eventually short-circuit it-even though they may electrocute themselves in the process. At least, "we came up with some pretty effective shark bait," says an AT&T spokeswoman.
At first, AT&T engineers didn't know what was causing the cable failures. Then they raised the cable and found rows of shark teeth
sticking out of it. "Sharks will always be attracted to magnetic fields," which the fiber-optic cables create, says James Barrett, an
AT&T engineering official.
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The species of shark was identified from the teeth, and the marine biologist who made the ID wrote a article about the incident for Natural History Magazine. The sharks extremely high bite pressure made armor impractical. To the best of my recollection, lower currents and better shielding solved the problem.

One year at the onset of cold weather my furnace wouldn't work. Being an electronics tech, I checked out the thermostat, voltages, wiring etc; everything seemed to work properly but the gas. I called the gas company and they explained that their pressure was only 0.25 psi. I tore into the gas hardware and discovered that a spider web was plugging up the nozzle.

Long ago retired from Bell System. Roaches were a persistent problem in Southern states operating areas especially in telephone sets. Since it was impossible to plug-up all of the holes (roach entrances) in the instrument We used a product called "Insectape" which was a tape square impregnated with some sort of repellant stuck to the inside of the baseplate. It worked wonderfully, wish I could recall who made it. I think that we originally located the product through HUD.

I worked for a company that made an electronic pump controller for domestic and agricultural use. The enclosure was vented so condensation could evaporate. We started to have epidemic failures in one particular part of the Australian outback and after some hoohaa found a tiny ant (almost invisible to the naked eye) was getting through the fine mesh protecting the vent and nesting in the electronics with the inevitable result. It turned out to be a species unknown to science! A really REALLY fine mesh solved the problem.

Had similar problem in NYC with rats, those thing eat everything.

I lived near the company where I used to work, so I was the call-in guy when the alrm went off. One night, we had three false alarms on one of the motion sensors for no apparent reason. Finally I happened to notice a shadow in the motion sensor. A moth had moved in, and seemed to have an amazing ability to move in front of the sensor each time I fell asleep!

i've seen where mice make nests in subwoofer cabinets. still haven't figured out a "humane" way to keep them out. steel wool would detune the box. screening over the port would hiss. the only way to keep them out is to put strips of adhesive backed copper foil in the port opening connected to the subwoofer's power supply.

I have been to AM bvroadcastantenna tuning units in the south of the US where fire ants had invaded. With several kilowatts of RF, the RF loving ants quickly fried and piled up in foot high drifts!

The only thing we found that would keep mice out of the equipment was packing every small opening with steel wool.Those critters will eat through just about anything else.

I had the roach problem with a control box in Metairie Louisiana. MY evaluation, based on how well the box was sealed, is that roaches can spontaniously generate out of air. Boxes of mothballs and bug killer were the solution.

From the wikipedia page for Grace_Hopper (no link cause URLs are disallowed in comments).
"While she was working on a Mark II Computer at Harvard University in 1947, her associates discovered a moth stuck in a relay and thereby impeding operation, whereupon she remarked that they were "debugging" the system. Though the term computer bug cannot be definitively attributed to Admiral Hopper, she did bring the term into popularity.[12] The remains of the moth can be found in the group's log book at the Smithsonian Institution's National Museum of American History in Washington, D.C.[13]"
The wikipedia page also includes a photo of the log page.

Back in the day of full height 5-1/4 floppy drives one brand had a door that when left open was large enough to let a mouse to get in and eat the very tasty wires to the R/W head.

I have seen air conditioner contact relays fail because of sugar ants that love the grease around contacts. They get squashed when the contactor engages, causing corrosion of the contacts. I report the failure as too much "antacid" applied to the contactor.

In our customer repair dept., it was a ritual to "fume" and clean all Florida units (and some other warm humid states) due to roaches. Most failures were due to roaches and their droppings. Roaches like warm electronic enclosures.

Houston, TX: Fire ants build nests in the outside electrical outlet boxes and occasionally cause a blowout of the outlet.

I have seen spider webs in lighting control centers, but all that did was kill the spiders, so ne problem there. However mice and ground hogs have the strongest teeth in the universe and can chew thru most electrical cables.
And then there was the deteriorated concrete light poles. Only 2 things will hurt this pole, a vehicle hit, or dog urine will make it crack.

That's what conformal coating is supposed to prevent

I had heard at one point that the reason we call the process debugging was that those very same roaches' cousins would enjoy the warmth of the vacuum tubes used to make the gates of early computers. They would get between battery and grid then conveniently die. The circuits needed to be debugged to get them working again. Is that Hardware or Software?

I have seen snail tracks eat the soldermask, solder and copper from circuit boards.

We had the same problem, except with mice. Mouse urine is highly corrosive on printed circuit boards, so the outcome was not as favorable, however.