Spicy Solution for a Foxy Problem

Scientific fieldwork in Alaska seldom runs smoothly. Study sites can be hard to reach, weather rarely cooperates, bears looking for snacks can demolish a camp. Then there's the problem that Frederick E. Nelson encountered on the North Slope: curious foxes.

As he reports in the British journal Nature, Nelson was making measurements of ground temperatures in the vicinity of Prudhoe Bay. A fox den was near one of his study locations, and the foxes were gnawing the plastic-sheathed electrical cables. Arctic foxes are small, as foxes go, but they have sharp teeth and--evidently--stubborn dispositions. At least the fox family near the temperature-sensing stations did; once they'd ruined one cable without finding anything edible, they'd chew up another one. Nelson's experiment was endangered by a furry demolition team.

Killing the foxes was unacceptable, but so was letting them ruin the study. A good field scientist learns to improvise with materials on hand, and Nelson had on hand the copious resources of the Prudhoe facility. He also had a good idea, which he stated with poker-faced formality in his response: "Many workers in the petroleum fields of North America are natives of the Gulf Coast and eastern Texas, so hot pepper sauce is abundant in oil-field dining rooms. Its unpalatability to those not from the Gulf States suggested that it might deter funkier damage at our field sites."

Nelson hails from Rutgers University in New Jersey, which may explain his odd view of Tabasco Sauce, the McIlhenny Company's fiery condiment. However, he explains it in terms of pepper potency and biological effects. The substance that gives hot peppers their kick is capsaicin. It's actually nearly tasteless and odorless, but it does stimulate pain receptors in the mouth and throat.

The intensity of that stimulation is quantified in Scoville units; the higher the Scoville count, the hotter the pepper. A typical salad-bar chili pepper may score near 2,500 Scoville units, while a Cayenne pepper raised in optimal conditions can score 25,000. The torrid Tabasco ranges from 60,000 up to a fearsome 80,000 Scoville units. Humans can acclimate happily to this level of irritation--at least some of them can--but laboratory rats never overcome an aversion to hot peppers.

So Nelson had some scientific support for his idea as, bottle of Tabasco Sauce in hand, he set to work on the replacement cables.

Simply painting the sauce on the cables wouldn't provide long-lasting protection. He stretched the new cables out, coated them with silicone sealant from a caulking gun, then spread the sealant with a cloth soaked in pepper sauce. While the peppered silicone was still tacky, he spread a liberal layer of pure sauce over the cables' surface. When the cables were perfectly dry and set, they were installed at the study sites.

Evidently North Slope foxes have New Jersey tastes. Animals visited the stations, and scientists making routine site visits found a few shallow toothmarks in the outer layers of sealant. No toothmarks fully penetrated the cables. The heat of Tabasco peppers is one kind of warmth that lasts through winter, too. For the remaining two years of Nelson's study, not one of his instrument cables was damaged by foxes.

Nelson offered his experience to help colleagues elsewhere who may find their equipment subject to predation, but I keep speculating that he really may be onto something here. Would granaries painted with pepper sauce prevent rodent invasions? I'll let someone else test the efficacy of pepper-soaked tents for keeping bears out, though. For now, I'm content to use a proven fox repellent on nachos and burritos.