A dedicated dad

This weekend sees Father's Day (is your card safely in the post?). For most birds, it's the mother who does the bulk of keeping the eggs warm and later caring for the chicks, but for some it's Dad who takes over...

The red-necked phalarope is a rare and very interesting bird. It's a wader which breeds mostly in the Arctic (in Europe, Asia and North America), but there's also a small population in Scotland (you can see them at our nature reserves at Loch na Muilne, on the isle of Lewis, and Fetlar on Shetland).

Interestingly, it's the female phalarope that's more colourful, and she gets to do all the courtship displays and 'singing'. The male gets lumbered with the job of keeping the eggs warm, looking after the young - his duller feathers help keep him camouflaged while sitting on the nest.

Here's how things work in the rather unconventional phalarope household.

Wham, bam, thankyou... sir

The female red-necked phalarope chases males and competes with other females for a breeding territory. Of course, the female lays the eggs, but that's where her involvement stops.

She leaves the male, who incubates the eggs and looks after the fluffy chicks, which are able to run around soon after hatching.

After doing her bit, the female may pursue another mate and lay another clutch of eggs, leaving the dads to look after things. In fact, she might only be in the UK for six weeks!

Then she's free to leave and make her way to the tropical oceans to spend the winter feeding on plankton far out at sea. For a bird which weighs little more than a house sparrow, it's quite an extreme lifestyle, but with their semi-webbed feet, phalaropes are up to the task.

Big daddy or little daddy?

In species where females do the 'normal' thing and do all (or most of) the caring for the young, the female is usually smaller than the male. It's easier for a smaller individual to carry out the hard work required for caring for chicks. Some scientists also think that a shorter beak might be more helpful if you're the parent who's helping small chicks to feed in their first few days of life.

Because egg-laying takes up energy and resources, it makes sense for the female red-necked phalarope to be a bigger bird than the male (this difference is also seen in birds of prey - for example the female sparrowhawk is up to 25 per cent bigger than the male).

But what's less clear is why male phalaropes have taken what's more commonly a 'female' role...