Friday, 10 September 2010

Musings on Eleanora's falcon

I am still at home in Bulgaria for my last week before my return to Libya. I have had time to muse! My musings have been about the forthcoming autumn passage. My mind went back to the sighting in May (see blog) of large numbers of Eleanora's falcon drifting through the middle of urban Tripoli in ones and twos over a four day period! 

illustration of Eleanora's falcon by Naumann, Wikipedia

What was going on? Collin's latest European guide shows the bird (which nests in the western Mediterranean and in Italy and Greece) migrating on the north side of the Med hugging the coast down the Red sea to Madagascar. This was the received wisdom until very recently.

However this doesn't support my own observations! and has been challenged (rebutted?) in a wonderful  paper called "Autumn Migration of Eleonora’s Falcon Falco eleonorae Tracked by Satellite Telemetry". This was in  Zoological Studies 48(4): 485-491 (2009)and was written by Pascual López-López, Rubén Limiñana and Vicente Urios.

Here's my take on things:

Libya has not been reported to be on the migration routes of many raptors. The big ones certainly seem to prefer crossing in and out of Europe at Gibraltar and Istanbul. However, it is increasingly looking like that under-reporting may have distorted peoples view of the number of raptors migrating through Libya.

In the telemetry paper two birds from the Baleaic islands were found (in autumn)  to fly more directly towards Madagascar right through Libya (see the two black routes with dots below) and not hug the northern Med coast (as in Collins) or go through the middle of the Med (as in the black arrows in their own map -see below)

map taken from "Autumn Migration of Eleonora’s Falcon Falco eleonorae Tracked by Satellite Telemetry" by Pascual López-López, Rubén Limiñana and Vicente Urios.

The red arrow is my observation of large numbers Eleanora's falcon migrating back in spring. I am not going to speculate on what route they took to get to Tripoli from Madagascar! 

So suddenly it looks like Libya may be on the most important route in both spring and autumn for the Western populations of Eleanora's falcon. Not bad considering two years ago most people though they by-passed the country altogether.

1 comment:

  1. I am sure there are more routes than shown by satellite tracking, which only shows a few individuals in selected populations. In September I saw a bird in Khartoum, which is well away from the migration routes and the first sighting for Sudan - though it has been recorded on the Red Sea coast by satellite. It seems that there is a lot more information coming out now about this species and it would be worth submitting your information for publication in the African Bird Club journal to get it known.