Thursday 17 September 2009

The cutest thing...

Ok, so you all remember that shorebird conference I went to a couple of weeks ago? Well, what I didn't tell you at the time was that there were a couple of things mentioned in the talks that were bugging me because I didn't have enough background knowledge of shorebirds to understand them. One of them was why they always count shorebird populations as the number of breeding pairs when quite a decent percentage of the birds are non-breeders (and as a non-breeder myself I take offence at the suggestion that we are not as important as the breeders). I still don't have the answer to that one, but as to the other question that was bugging me so much, I stumbled over the answer to it quite by accident when I was reading a reference about something else.

It is a very important fact in shorebird biology that most beach nesting birds get very easily disturbed by people and dogs walking past them and will leave the nest whenever such disturbances come too close. When the birds are meant to be looking after the eggs, but spend most of their time running away from big scary things it results in problems (as in, the eggs never hatch). But, if you think about it logically, it doesn't make sense:
  • Shorebirds nest in summer
  • Summer is hot
  • Shorebirds nest directly on the sand
  • Sand in summer is very, very hot
  • A bird sitting on the eggs will only make them hotter
  • Hot eggs cook
So I kept wondering how the birds manage to keep their eggs in the right temperature zone so that they would be warm enough to develop, but not hot enough to cook. All I could come up with in answer is that they stand over the eggs and shade them, but I couldn't convince myself that shading by itself would be enough to cool the eggs.

Hooded Plover parentals standing over nest

Another Hooded Plover nest with 3 eggs

Turns out I was right. Birds do shade their eggs, but it isn't all they do- they do this amazingly cute thing called "belly-soaking"

"Belly-soaking" is when a parent bird notices that the eggs are too hot, runs from the nest into the water up to its belly, gets its tummy feathers all wet, runs back to the nest, and puts its now cold and wet tummy on the eggs. During hot days the birds do it almost constantly so its very time consuming and energetically expensive for them, but its also very effective. And cute. So very, very cute. I was rapt when I found that the answer to the question that had been bugging me was so simple and so cute. Now I love my birdies even more :)

Hooded plover chicks in nest

6 comments:

Joolz said...

That is very amazing. God's plan for even the shorebirds is awesome.
See parents are good things.

Emma said...

I never said parents weren't good. In fact, I'm pretty sure that most of my friends will have heard me talk about how great it is to be able to get looked after by your parentals.

Emma said...

Hint, hint, I'm going to need a bit of looking after this weekend.

Joolz said...

You got troubles, or just the miseries?

Emma said...

I've come down with the flu and its making me feel really nasty.

carrot said...

hey em! Luv the cute photos. I never knew they did that! I'll hav to tell Ray...