An armchair tick...

I have already described the compulsiviness with which birdwatchers compile lists of bird species they have seen in a year. Lists may relate to their county, country, garden, or even on their route to work. The acquistion of a new species for a list is known as a "tick": hence, "year tick", "garden tick", "holiday tick" and so on. The most important tick of all is the "life tick" (also known as a lifer) which gets added to one's "life list" when seen anywhere for the very first time.

I had to wait until retirement before I added Imperial Eagle to my life list. It was the Spanish sub-species (i.e. "race" or "form") which I saw in Extremedura in April 2009.

Spanish Imperial Eagle Aquila adalberti, Extremedura, Spain, April 2009

My next Imperial Eagle was the "Eastern" sub-species which I saw in Burgenland near the Austria/Hungary border earlier this year. Very exciting, of course, and a new tick for my Austria list. However, being only a "sub-species" I could not claim it as a "life tick".

UNTIL:

I have only recently discovered that taxonomists have since got to work with their DNA analyses and have proclaimed that the Spanish sub-species and the Eastern sub-species are sufficiently genetically and ecologically distinct as to be regarded as quite separate species, rather than mere sub-species.

An Eastern Imperial Eagle Aquila heliaca, flies overhead at the March-Auen, Austria, 2010

Hooray! That's good! As I sit in the comfort of my arm chair as I type this, I can add Eastern Imperial Eagle as another "tick" to my life list without doing any extra work!

This is known as an "armchair tick"!