Athletic squirrel

[treecreeper]

I've just been out to get the paper. On the way back I saw a grey squirrel go through the fence by the railway line, apparently intending to reach the woods on the other side of the line. I was intrigued how it would get across the live rail so I poked my head over the fence. I was just in time to see the squirrel make an enormous leap, clearing the nearside track and live rail in a single jump, landing between the two live rails. It cleared the other live rail and farside track in two more jumps, avoiding all the rails.

The squirrel surely wouldn't have done this had it not been aware of the danger from the live rail. I'm wondering where it got this knowledge. The rail is about 750V so I can't imagine it survived an earlier shock and remembered. Perhaps it can detect the electric field? Also interesting is the way the squirrel seems to regard all the rails as dangerous.

[Teal]

Treecreeper,
A lovely thought about you squirrels learning about the live rail, but my guess is that they just jump an obstacle not the live rail per se. In any event, if the squirrel jumped onto the live rail without any part of it touching the ground it would not "earth" and would thus not be electrocuted. It is also quite possible that even if it did earth (i.e. its tail touching the ground with all four feet on the live rail) , there would be insufficient 'contact' for the current to electrocute the squirrel (long time since I did physics but I think its all down to potential differences) its quite complicated. We have an electric fence round the chickens to keep the foxes out, but the chickens treat the fence with impunity and do not get a shock when touching it for the same reason!

[treecreeper]

Thanks for replying Teal, I was resigned to the thread sinking into oblivion unanswered . The squirrel simply jumping an obstacle is more convincing...squirrels are probably not that well up on physics

[Picidae]

Originally Posted by treecreeper

Thanks for replying Teal, I was resigned to the thread sinking into oblivion unanswered . The squirrel simply jumping an obstacle is more convincing...squirrels are probably not that well up on physics

Teal's explanation is pretty spot on. Squirrel's will jump anything if it can be avoided by climbing! With regard to the physics, Squirrel needs no classroom education, physics has it's own agenda! It's why small birds don't get electrocuted just landing on single powerlines however, Storks etc can get electrocuted if they actually land on the conductors which are connected to a ground line and so can large birds like eagles/swans etc if their wings touch a ground line simultaneously with a power line or they touch two powerlines at the same time (it's something to do with the potential differential between two parts of the animal/birds body which are touching the live wires ie. the greater the ratio between the distance of the two parts touching compared to the mass through which the current flows, the greater the risk of electrocution)

[Meta menardi]

Animals can get very upset by straight liney sort of things. I have milked 2 cows, during my as a dairyman, that would not cross a hosepipe. They would rather turn and fight, and that is rare in a cow.

[Vincent86]

Animals can sense danger. They can sense almost anything.