Tuesday, 27 March 2012

Lilith Owl in the UAE

A pair of Lilith Owls.

If ever there was a dynamic science, then taxonomy is it. The perennial question, when has an organism diverged enough to be called a species, is one that is not easy to answer. There are many definitions of species in science today and certainly in the world of birds, many species are being split from close relatives into species in their own right.

World listing is fraught with difficulties, birders are equally divided into two main camps:

  • The more conservative approach of the Clements checklist
  • Or the more up to date and dynamic approach of the International Ornithological Congress (IOC) Checklist.

I am a firm supporter of the later organisation, as I believe it is more up to date in its philosophy and ready and eager to utilise modern scientific breakthroughs to try & solve taxonomic problems. However, there is no right or wrong approach here, both have its merits and its detractors.

In typical rocky habitat in the desert.

Something has caught it's attention!

Little Owl has a wide distribution across Europe, North Africa and Asia. Thirteen races are currently accepted by most authorities. Within these races, are marked differences in plumage, calls and habitat. It is these fundamental differences, which some authorities see as enough evidence, to split off some of these races, into species in their own right.

This species pairs for life & are
very faithful to their territory.

Notice the less defined facial disk on this bird.
Characteristic of Lilith Owl?

The races found in the Middle East would appear to have one of the more stronger cases for splitting and a recent paper in the journal Dutch Birding sets out the case for speciation in this complex.

The scientific name for Little Owl is Athene noctua. A third name (called a trinomial) follows this. So the race of Little Owl we have here in the deserts of the UAE, becomes Athene noctua lilith.

However, we also have the more normal looking Little Owl in the UAE mountains, which in my view, strengthens the case for the race lilith being elevated to full species concept. The two groups of Little Owls in the UAE are separated by geography, habitat and they have different coloured plumage and crucially, slightly different calls. The vexed question of whether these two forms ever come into contact with each other, has yet to be established. And if they do, do they interbreed? If this is established to happen, then this would weaken the case for splitting lilith off as a full species in its own right. 

If you follow the recent trend, then the former race of lilith now becomes Athene lilith. A full species in its own right, with other races in the Middle East:

Athene glaux

Athene indigena

The Lilith Owl (Athena lilith) within the UAE seems to be  found in desert habitats, more in piles of rocks or small cliffs amid the widespread sand desert. It seems to shun the use of trees, which is another difference from the other forms of Little Owl. The form which is familiar to us European birders seems to be confined to the mountains and foothills and gravel plains surrounding the mountains.

Whether you believe that the form lilith has deviated enough away from its ancestral core form, is debatable and probably will only be settled by modern genetic studies. But it sure is fun seeing these two forms (or is it species)? in the UAE.

  • Current scientific thinking is that Little Owl Athene noctua has ten races.

  • Lilith Owl Athene lilith is a full species with the races glaux and indigena.

However, this situation could change, as it seems curious that the desertae race found in North Africa, is currently not split from Athene noctua. Watch this space!

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