Black-necked stilt - Himantopus mexicanus (as per the IOC)
This has to be a contender for one of the most graceful birds on the planet. Not so far off an Avocet and of course in the same family as the Western Palearctic's Black-winged stilt. I have run into a controversy with myself today though - is this a different species or simply a subspecies of the European bird. It all depends on which global bird list you follow.
The European birds have no black markings on the neck at all - to my eye they look completely different. My Handbook of the Birds of the World in a very imperialistic tone merely categorises this as a sub-species of Black-winged Stilt. Sibley on the other hand the premier hand-held text book for the US states that this is a separate species. How far apart do populations have to drift before they classify as a separate species altogether. I think I have discussed this before with gulls - how around the world say a Lesser Black-backed gull will morph into 3 or 4 species with sub-sets as you circle the planet. We see the same thing with Herring Gull morphing into Yellow-legged Gull and then Caspian Gull. What's the scientific answer. I could just rely on Sibley or find a list that states that Mexicanus is a separate species. The debate is between the "splitters" and the "lumpers". One thing is for sure is that I have discovered that I haven't posted a Black-winged Stilt at all yet which could make for a very easy win with a 20 minute drive to the Creek in Dubai ! (August ticks being hot to come by but I know an air-conditioned hide).
It does appear that the AOU (American Ornithologist's Union) treat this bird as a separate species and really then I should relabel this page Black-winged Stilt and then describe this as a sub-species based on the Handbook. The classic scientific definition to actually answer my own question is that a species is the largest class of hybrids of a collection of animals capable of sexual reproduction resulting in viable offspring. That doesn't seem to be the end of it though with birds as every Tom Dick or Harriet (I hope) wants a species names after him or her so tries to split them out with voice, DNA, behaviour, and looks all being thrown into the mix. Someone declared a new owl species in Oman down the road based on a different song - now apparently they are doing it with some owls on every tiny Pacific island. Logically if you follow every variation you must end up with tens of thousands of different species. Are the Galapagos finches with different bills for each island species or sub-species.
When Darwin travelled on the Beagle he went not as a scientist but as the Gentleman companion to the captain. A bit like Maturin to Aubrey from the O'Brien novels but without leg-sawing duties. Darwin got interested in the question of why there were so many species when a man told him that he could tell which island a giant tortoise came from purely based on the shape of its shell. Tortoises from dryer islands had a raised shell at the front entrance which allowed them to crane for the higher branches of the vegetation something like a giraffe in the bush. On more irrigated islands the tortoises lacked this adaptation as they only needed to graze on the ground to survive. In times of drought on the drier islands only the tortoises with the adapted shell's survived as they had more opportunities to feed and so in time all non-adpated tortoises died out and all the offspring had the raised shell. I wonder why the american stilts have black-necks ? Accident or opportunity ? Fashion or utility ?
I am none the wiser just now for my research but it appears that for this Stilt grouping you can treat them as 1 species with 7 sub-species of 7 seperate species or even 2 species each with 3 or 4 sub-species - there are other permutations. I think we leave this debate for now - it doesn't impact on me tactically until I have to post up another stilt and come out as a splitter or a lumper. I did say in my "rules" which list I was following and jumping ship is probably not then appropriate. A shame but there you go.
How about just admiring the bird ?
By reference to the size of its body those have to be the longest legs that you can see on a bird. Disproportionate even beyond cranes and herons. When it flies the long trailing pink legs are ridiculous - somehow they don't snap when it lands.
I am torn back to the controversy - "most sources recognise 6 species in 2 genera" says Wikipedia. I think I need to go back to my rules and settle this before I post - Himantopus himantopus mexicanus (a tri-named sub-species) or Himantopus mexicanus (a species proper). We go by the rules of this site or we have to change the rules. Well the Task page of this site says (back on the day "1" when I set out on this journey or whenever I first stumbled into this issue) that I am going by the IOC list of birds - I think that's the International Ornithologists Committee or Converntion ...Do they have this much difficulty in Bake-Off - yes they do....do they vote ? They must vote after a scientific debate - can anyone go and wave a picture of bird with a new coloured eye ? so I am off to the IOC list to see what the birdy gnomes who have got themselves elected to that body and get a vote er... have voted. What are the politics of it - is it a self perpetuating oligarchy or is it elected ? Can any numpty get on it or do you have to have a degree in birdology ? - is it riven by great schisms between lumpers and splitters. It must be the fault line of the battle but in general a splitting body if it has made it to 6 species for stilts whereas the Handbook of the Birds of the World is stuck at 1 - a bit conservative and European me thinks.
So for the record its the IOC list (sounds nice and official like IMF or IWB or WWF) and I won't get thrown or debate this publicly anymore. If my Handbook lists something as a sub-species I will check the IOC list and that will be that. It looks very different to me and I had to fly across an ocean to get it ! Whichever pair of stilts made that crossing and had descendants with lovely bi-coloured heads deserve separate species status on Neil's Daily Bird. Hallas.
It is a separate species according to the IOC. Marvellous. Looks like a trip to the creek then and we can do a compare view ! Or is it marvellous - that means I have to go chasing 5 other species of stilt rather than relying on this one picture from Christmas, Florida (thats the town not the season).
Lets have a butterfly to close the issues. Some sort of swallowtail - haven't a clue - next to the car park when I realised I hadn't brought any lunch and was starving and was in Hicksville USA on a Sunday with nothing but Wolf FM the sound of country for company...howling out to you !
Black-necked stilt, Himantopus mexicanus
Orlando Wetlands Park, Florida, USA
July 2015
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