People love watching foxes jump head first into snow. But why do they do it?
They are hunting rodents. Many rodent species travel in tunnels under the snow. This protects them from Aerial predators like owls and hawks. But foxes are on the ground and have a good sense of smell, so they can sniff out (literally) the food. Once they assess their target, they leap into the air and dive headfirst into the snow to make the catch. Which is why I have seen the act referred to as “Mouse Diving” which you can learn about on a site called Fox Folk.
Interestingly, some species of fox are significantly more successful at this when facing towards magnetic north. Scientists now believe foxes may be able to detect the earth’s magnetic field to help guide the trajectory of their jump.
You may wonder if it is smell but it is actually hearing that they use to locate the mice. It’s mostly hearing with regard to mice under snow, at least for the final attack. Think about how long it would take for scent molecules to penetrate a foot of snow.
Recent research suggests a magnetic component as well, as their success rate in snow hunting has been measured to be much greater when they face approximately 20 degrees off of magnetic north, regardless of time of day or weather. The leading hypothesis is that it helps find the distance, but we don’t know for sure yet.
Here is a beautiful example of the trajectory of a fox pounce.