Red-billed Teal, Hazeva, Israel, 5 March 2016
Long before the trip I'd been a fan of this bird being the real deal. Israel boasts the only previously accepted Western Palearctic record of the species (in June - July 1958) and of course has a strong track record with producing extremely rare sub-Saharan African vagrants. Barak Granit wrote an interesting article on the Israel Birding Portal website which coherently summarises where we are seemingly at regarding this latest bird. His conclusion was that it's ultimately still up for debate, though Barak seemingly falls on the pro-wild side (e.g. "An escape scenario is just plausible as well, but the evidence doesn't support such a scenario").
Red-billed Teal, Hazeva, Israel, 5 March 2016
- The bird is behaving in sedentary fashion (i.e. it has been in Israel for two years and currently shows no signs of leaving)
- The bird has hybridised with a Mallard
The bird's sedentary nature
Here I quote BirdLife International (2012): "This species is mostly sedentary or nomadic, but may disperse long distances (up to 1,800 km) in the dry season depending on the extent of flooding".
Red-billed Teal is a species that often moves based on the availability of water. If suitable habitat is present, it does not need to move. If water is not available, it has the ability to move large distances. If it is normal for this species to disperse the best part of 2,000 km in search of water, imagine what a vagrant might achieve? Red-billed Teal routinely occurs as far north as Sudan. From here it is really not that far to travel to southern Israel, particularly when you consider the Nile acting as a northward funnel for sub-Saharan species. If a vagrant teal is driven north by a lack of water, it could feasibly end up in southern Israel (as many other African species have previously). If it then finds a constant water source to its liking, as this bird has, why would it need to move? The current notion to reject the record based on its sedentary nature (a completely natural part of the species' ecology) therefore doesn't make much sense.
One should also consider other examples of long-staying African vagrants. Israel currently has one (the Bateleur on the Judean Plains has now been present for almost a year), possibly two (Yellow-billed Stork in Bet She'an potentially present a year or more?). Elsewhere there is a long-staying and regularly returning Grey-headed Gull in Italy (currently present for its fourth calendar year) and, as of March 2016, Cape Verde continues to host a single Black Heron (this bird having originally turned up alongside another in March 2011). Before this there was a Black-headed Heron there for over two years. These are just recent examples and there are no doubt many more.
Hybridisation
Barak Granit refers to the occurrence of hybrid offspring alongside the Red-billed Teal as "much more worrying", but I do not agree with this. Dabbling ducks (Anatinae) are notorious for rife hybridisation, particularly among vagrants. It is a fact of life that Anatinae are very much advocates of 'free love' - hybridisation between species occur in normal circumstances, and not just in a vagrant context (where a lost individual will naturally look to breed with its closest available relative, if possible). If this is genuinely being used as a factor against the Israeli Red-billed Teal then, using the same logic, we should look to reject all those American Black Ducks that interbreed with Mallards in Britain, Ireland, the Azores and so on. Similarly any vagrant American Wigeon breeding with its Eurasian counterpart (or indeed Green-winged Teal with Eurasian Teal etc) would therefore be discounted as a wild bird. The fact that the Arava Red-billed Teal has bred with a Mallard at some point is, in my opinion, normal behaviour for a wild bird and in no way should be viewed as an indication of a captive/wild bird. Hybridisation is a true red herring in the 'wild or escape' debate.
On 5 March 2016 the Red-billed Teal was seen alongside two hybrid offspring - both of which are pictured in the images above. The mixture of RBT/Mallard features is quite obvious.
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