The world recently gained a new species of bird thanks to the research of George Sangster et al. who this year published their paper suggesting that the subspecies of Blue Chaffinch found only on the island of Gran Canaria, should be split into a full species from the Chaffinches found on Tenerife. The reasons given for this split include differences in mitochondrial DNA, differences in call (the birds can tell the difference anyway), song and minor plumage and structural differences.

In case you wanted to know, the nominate subspecies of Blue Chaffinch is Fringilla teydea, whereas the ‘new’ species is Fringilla polatzeki – present in less than twenty kilometres squared of Gran Canaria. When they were just one species the Blue Chaffinch was considered Near Threatened due to wildfire risk to its habitat, disturbance and collection for the cage-bird trade. Recently however, the species has seen an increase in population on Tenerife and may have been down-listed to Least Concern; this may still happen for the Tenerife birds but the new guys are not looking so good.

With only around 250 individuals surviving in a very small area of Gran Canaria, Fringilla polatzeki will most likely be categorised as Critically Endangered – and gain the title of Europe’s rarest songbird. This revelation will change things – already under conservation plans polatzeki will require even more significant effort to prevent its extinction. Whereas before its loss would have been unfortunate but not catastrophic as it was ‘only’ a subspecies, now we face the loss of an entire species (and a very pretty one too). Not to mention that the other Blue Chaffinch species has now lost 250 birds from its population.

Threats to the Gran Canaria species are mainly habitat fragmentation (thanks to commercial logging and forest fires), inbreeding, collection for the bird trade and heavy disturbance from recreational use of the forests. This whole situation is an intriguing one though; when the bird was just a subspecies its loss did not seem as terrible as it now does. It has got protection but it seems that the success of the Tenerife birds made the recovery of the Gran Canaria group less important. Now that it is a species in its own right though I suspect that panic to save it will ensue and a lot more thought put in than was previously.

This begs the question of what is really important in this case? Are the individual birds important? Are the subspecies important? Are the species important? The categories are made by humans, the actual living Chaffinches on those islands don’t know or care if there are only 250 of them left or if they are a full species or only a subspecies.

When we talk about biodiversity it is often supposed that it is the preservation of species and habitats that are of paramount importance – but should not biodiversity include subspecies as well? After all, genetic variance and the strength of a species gene pool are quite important in maintaining healthy populations and ensuring the durability of a species over time. Nature is a lot more fluid than humans like – we want everything to fit neatly into a section or graph or category, but nature blurs our lines – species can and have melted together to form new ones or broken apart into many new species.

Not to mention the embarrassing fact that we humans very often get our categorization wrong – thus imperiling entire species to extinction because we neglected them as ‘just’ subspecies. Hopefully the Gran Canaria Blue Chaffinch was recognised just in time, but how many others await (re) discovery?

Well I can name one more actually, because another bird species was also newly recognised this year – the Iberian Green Woodpecker – split from the European Green Woodpecker familiar in Britain. This new bird once started off (a very long time ago) as just a population of one species, but over time changed (thanks to isolation) into its own thing. Given time it may change even more, perhaps splitting itself into more species, or even mixing back into the original Green Woodpecker species. Currently, at this exact moment, it is a full species with its own name and everything; it is important that it exists – but was it less important when categorized as a subspecies? Of course not, even if it had actually, genetically and physically been a ‘sub’species it would still have been important to nature, performing its role, filling a niche.

On the other hand, for birders there are now two new species in Europe to go and see – two more on the list!

(Photo by Bartkauz)

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