Bird on a wire!

I love it when I get questions on the blog, that’s what it is all about! Today some junior scientists (who can sometimes be found here) wanted to know….

Why do birds not get electrocuted when they sit on electrical wires?


photo credit: philografy via photopin cc

A very good question, do you know the answer?

Well first up, some electrical wires are insulated so that even if we touched them we would be safe (but I am not suggesting that you try that!) Other wires rely on air as their insulation so they pose the most risk to anyone touching off them.

For electricity to flow tiny particles called electrons need to move! When we use a battery in a toy it has a plus side and a minus side and electrons travel from the minus to the plus creating a flow of electricity. These electrons need something to move through… we call the thing they move through a conductor. A good conductor is something that allows electrons to flow easily through it; electrons cannot pass so easily through a bad conductor.

Electrical wires are often made of copper which is a very good conductor. The electrons are very happy because they can move easily through it. A bird’s body is not such a good conductor so the electrons would rather stay flowing through the copper wires than flow through the bird. So the birds remain quite safe.



Here is a good way to think of it…. which would you find easier to swim through… nice clear water or thick oozy mud? If you want to move quickly the water is a lot easier to move through, isn’t it? Just like the electrons moving through the good conductor.

So while the bird is sitting on a wire high up in the air the electrons choose to keep on their path through the copper wires and not pass through the birds at all. But what needs to change for the birds to get an electric shock? We already spoke about the fact that electrons like to pass through good conductors rather than bad conductors but electrons also like to go from places of high voltage to places of lower voltage. Voltage is really just electrical pressure, so electrons like to move from a place where the electrical pressure is high to a place where it is low.

While the bird stands on the one wire there is very little difference in voltage BUT if it was to touch off a second wire of a different voltage then it will find itself in trouble. The electrons will flow from the wire of the highest voltage to the wire of the lowest voltage, passing through the bird. This means the poor bird will get a very big electric shock. Also there is no voltage on the ground so if the bird was touching the ground while touching the wire them the electrons would flow from the wire (high voltage), through the bird and into the ground (no voltage). Not a good situation for the bird at all.

In theory, if we were to hang off an electrical wire in mid air, we too would be unaffected, just like the bird. However, if we are standing on the ground when we touch a wire the electricity will pass through us to reach the ground and we will get an electric shock. NOT A GOOD IDEA!

The important point in all of this is to remember to leave the wires… to the birds!

I hope you liked this explanation, if you have any questions or comments please leave them in the comments below… I always love to hear from you! And remember… if you or someone in your family has a question they would like answered here on the blog please do let me know!


Science blogger and writer; Owner of Dr. How's Science Wows; Mother of three junior scientists who have taught me that to be a great scientist you need to look at life through the eyes of a child!

8 thoughts on “Bird on a wire!

  • January 23, 2014 at 7:15 pm

    Loved it! I was never really interested in science as a child, but reading this I’m thinking that I was mistaken x

  • January 23, 2014 at 11:53 am

    Very interesting – I am gad Sinead was asked the question and sent it on! I fear you may be inundated with all of our questions now … 🙂

    • January 23, 2014 at 11:56 am

      Thanks.. that would be great, love questions here.. that is how the blog started… questions from my own children ;0)

  • January 23, 2014 at 10:45 am

    I don’t remember that film Maud but will check it out! With regard to your question on those orange plastic balls I think they are called overhead marker balls or Aviation marker balls. They are usually there as a visual marker for aircraft… often found in certain places near airports they are usually placed on specific flight paths.

    I am pretty sure that we have them here in Ireland too. Some say that they are also there to stop large birds like swans and geese from flying into them and can be found near bird reserves. I am not so sure if this is true or not!

  • January 22, 2014 at 11:45 pm

    We just recently re-watched the film The Ice Storm, if you remember that. Very good lesson in it to leave fallen wires alone.

    I have a question, though. Some wires I’ve seen here in the US have what look like orange plastic balls around them in one or two places. Have you any idea what these could be for?

  • January 22, 2014 at 11:07 pm

    That was a good question and a very interesting answer.

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