Keep your sub-species pure.

The same is true for Masked Finches and the White-Eared Masked, White Bellied Crimsons and Black Bellied Crimsons and several more. Pure lines of these native species are important for future research and may have value in conservation programs. Whatever the case NFSA is keen to ensure all breeders are aware of the importance of maintaining pure subspecies.

A particularly interesting example of subspecies where we do know something about the natural overlap zone between two subspecies is with the Longtailed Finch – Poephila acuticauda. This species occurs in two well defined subspecies across northern Australia – the Yellow-Billed Longtail (Poephila acuticauda acuticauda) which occurs in the Kimberley region of WA and extends eastwards into the Northern Territory and the Red-billed Longtail (Poephila acuticauda heckii) which occurs in the Northern Territory and east into Queensland.

In aviculture there is a wide range of bill colours, from pure Yellow-Billed and pure and deeply Red-billed birds through a range of intermediates with paler red or variably orange beaks. In the wild there is also an overlap of the two subspecies and orange billed birds occur naturally in this overlap zone. Dr Simon Griffith and his research colleagues at Macquarie University have researched this overlap zone in some detail and shown that the two subspecies overlap in a 150km wide region centred about 50km west of Katherine in the NT. In this region beaks are orange, but either side are yellow to the west and red to the east. The boundaries of the overlap zone does not appear to be moving and the research team is currently trying to measure how far genes of yellow-billed birds (genes other than those for beak colour) have infiltrated into the red-billed population and vice versa (Griffith and Hooper 2017).

The evolutionary history of the Longtail is interesting in that the Yellow billed and red billed Longtails were isolated for thousands of years in the west and east of northern Australia by periods of severe aridity during the last Pleistocene ice age which peaked around 21000 years ago. Much of Australia was much cooler and drier and tropical savanna woodland contracted northward to small isolated pockets which trapped isolated subpopulations of many species in parts of the north,including the Longtails.

The same mechanism is thought to have driven the segregation of head colour morphs in the Gouldian finch. The two Longtail subspecies which diverged during that period of isolation came back into contact sometime between 21000 and 14000 years ago when the tropical monsoon cycle in northern Australia was re-established (Griffith and Hooper 2017).

A good example of a subspecies we have already lost in the wild and probably in aviculture is the Southern Star Finch (Neochmia ruficauda ruficauda). This subspecies was in fact the nominate race of the Star Finch – the subspecies first described in science by John Gould in 1837 (note Star Finches were originally named Bathilda ruficauda ruficauada). It occurred from north central Queensland south to northern NSW and what is particularly interesting is that it was apparently described from specimens collected near Moree in northern NSW.

According to Neville Cayley in his 1932 book (Australian Finches in Bush and Aviary) Star Finches have never been seen in NSW again after that time. In his book and subsequent reprints, Cayley depicted only two subspecies of the Star Finch – the Southern Star (Neochmia ruficauda ruficauda) and the Northern Star (Neochmia ruficauda clarescens). Today three subspecies are recognised with the northern Star divided as the Kimberley Star (Neochmia ruficauda subclarescens) and the Cape York Star (Neochmia ruficauda clarescens) (see map).

However the Southern Star is now regarded as extinct in the wild and there is uncertainty around whether it was ever held in aviculture. Southern Stars are so distinctively different to the Stars we keep, with huge spots almost all the way down the front. We are fortunate to have images of specimens of the Southern Star from the British Museum (thanks to Milton Lewis). It is clear that the pattern and size of white spots on the Southern Star are distinctively different to the Stars we know today, with large white spots almost to the vent and only a small pale area of lemon on the lower belly. The other image shows a Southern Star with a northern subspecies and the difference in size is also very apparent.

The other two subspecies of the Star Finch are well known in aviculture. These are the brilliantly coloured Kimberley Star finch – Neochmia ruficauda subclarescens (which occurs in WA and the NT) and the slightly less brightly coloured North-eastern Star (Neochmia ruficauda clarescens) which occurs in Cape York. The Star Finches we now have in aviculture are undoubtedly derived from these two subspecies, some are pure Kimberley Stars, many are a blend and of course there are several mutations mixed in there as well.                           Whether there is any remnant of the Southern Star in our aviary populations of Star Finches we don’t know, but they are essentially lost to aviculture and in the wild.

Loss of subspecies has also been an issue with many of our foreign species, though here the damage is pretty much done. For example Australia used to have three blue waxbills – the Red-eared Cordon Bleu, the Blue-capped Waxbill and the Blue-fronted Waxbill (Kingston 2014). Unfortunately the latter species was lost partly through crossing with the other two. These days it is likely that we have Cordon Bleu genes contaminating Bluecaps as some breeders in the past (hopefully not today) have used Cordon hens with Bluecap cocks when they could not obtain Bluecapped Waxbill hens.

Similar things have happened with Orangebreasts, where we once had at least two subspecies, one with a variable but much richer orange through the chest and underparts in the male (Amandava subflava subflava) and one with paler yellow underparts and just a splash of orange on the chest of the male (Amandava subflava clarkei). Females of both subspecies look similar though clarkei was slightly larger. Today we have just a single blended “species”, but with huge variation in the extent and intensity of orange colouration in the cocks. With the inevitable preference and active selection for brighter orange birds we are probably selecting out the genetic background of the clarkei subspecies.

Of course we have lost many other species of foreign finches altogether, mostly because they only ever had small numbers and never developed a strong breeding population or were very difficult to breed in the first place. But losing distinct sub-species through hybridisation among subspecies is just negligence.

So we encourage all finch aviculturists to treasure and respect the species and subspecies we have and do whatever you can to keep them pure and viable.

Of course this whole discussion doesn’t touch on the issue of mutations in all species and the importance there of keeping pure strains of the parent species. That’s a topic for another time.

Acknowledgements

Many thanks to Cheryl Mares for images of Blackthroats and Longtails and to Milton Lewis for images of Museum specimens for Southern Star Finches.

References

Cayley, N.W. (1932) Australian Finches in Bush and Aviary. Angus and Robinson.

Griffith S. C. & Hooper D.M. (2017) Geographical variation in bill colour in the Long-tailed Finch: evidence for a narrow zone of admixture between sub-species, Emu
– Austral Ornithology 117:141-150.

Kingston R. (2014) The Finch – A Breeders Companion. Indruss Publications. ___________________________