Shag, Tally or Void?

Of late, the speed of taxonomic changes has accelerated to the point where I’m struggling to keep up with what constitutes a valid species and what is not. The word ’complex’ is featuring heavily in some of my field guides. It tends to be employed by those advocating for ‘splitting’. It is indicative of cryptic species hiding in plain sight.

Conversely what was once widely accepted to be multiple species can suddenly get ‘lumped’ back together as a singular species. I give you the newly minted - Common Redpoll. This despite the fact that the formerly valid species of Lesser Redpoll, Common Redpoll and ‘Hornemann's’ Arctic Redpoll could be readily identified in the field (at least for classic specimens). So confident was I, in my ability to do this, that I even fancied I could hear the tonal differences in their flight calls.

The balance between lumping and splitting sits on a pendulum, but the fulcrum can shift in either direction. The general trend, at this time, favours the splitters. But beware, the Umpire Lumpers may strike back.

When last I visited the Otago Peninsula in New Zealand in 2015, I reacquainted myself with a striking member of the cormorant, or shag, family (depending upon your preference) in the guise of the range-restricted Stewart Island Shag. (just to spice things up a little, it comes in two distinct colour forms, bronze or pied). In December 2024, on my most recent visit, I didn’t see a single Stewart Island Shag.

Sadly, the Stewart Island Shag no longer exists. Fear not, it hasn’t gone extinct, it’s just been torn apart. The birds nesting on Taiaroa Head are now Otago Shags and those on the islands around Stewart Island are now Foveaux Shags. Having seen them in both locations I have gained, by default, a shag. Can I tell them apart in the field? No!

Otago Shag © Jeff Clarke December 2024

What consequence is this having for conserving species? The jury’s out on that one, but species tend to attract more funding for research and protection, than do sub-species.

Is it having any consequences for me? Yes. It’s costing me a fortune in new field guides!

Well, I’m glad that’s sorted…What’s this? – STOP PRESS – Proposed Splits/Lumps IOC Version 15.1 (DRAFT) Recommend re-lumping of Otago and Foveaux Shags!

That’s it, I’ve had enough. Bring me a taxonomist, I have some lumping and splitting of my own to do! Grrr…