How's this for pretty feet?:

They belong to a pair of boobies - blue footed boobies Sula nebouxii. Boobies are gannets in UK language, and there are three species here. All are notable, for very different reasons.

The red footed Sula sula, nesting only on two small remote outer islands, are unique in that a local finch pecks their wings while nesting, drawing blood that the finches then drink thus enabling them to survive on the waterless islets and earning them the name 'vampire finches' - the only such relationship in the avian world. We won't get to see them unfortunately.

The third species of booby here is the Nazca booby Sula granti. This species is remarkable for practising obligate siblicide - I think the only bird in the world to do so. If you can't work out what it means you'll have to wait until I explain it in a forthcoming Blog. I bet you can scarcely wait. The tale is even more macabre than that of the vampire finches; nature red in tooth and claw.

By comparison the blue footed boobies are tame and dull. But pretty. Here are the owners of the feet pictured above:

This is a nesting pair on the island of Seymour Norte. The male and female are almost indistinguishable, which is their point of zoological interest. The plumage is identical - the difference is in the eyes:

This is the same pair from the side, male on the left. Can you 'spot the difference'? There is only one distingishing feature - the male's pupil is a pinprick, while the femal's is much larger, almost filling the iris (I hope that the downgraded photo that I have to use for the internet shows this as clearly as the original; if not you'll just have to take my word for it). Why this should be no-one has yet worked out. Both sexes dive for fish in an identical manner and eventually starve to death when their eyesight begins to fail at about the age of 12 years so that they can no longer catch fish. There must be a reason for the eyes. Any offers?