Friday 29 April 2016

Rescuing a Great Crested Grebe

I had a slightly bizarre start to yesterday. I was out the back of Langtoft, doing a circuit of my old patch, when I noticed this Great Crested Grebe sat by the side of a the road. Immediate reaction was that it had been attacked, hit by one of the many HGVs using this road or had collided with power lines, which it was sat below. It was trailing its left leg, which was covered in blood, and its left wing also looked quite badly bloodied.


Having returned home for a box, I went back to pick the grebe up. It was quite feisty but obviously couldn't move, so was easy to catch. After unsuccessfully trying to contact local RSPCA branches, I took it up to the exotic pet refuge in Deeping St James. Quite miraculously, they were able to confirm that it hadn't broken any bones in either wing and the leg seemed OK, if a little sore and bloody.


So with the prognosis positive I popped it in the car, drove it back up to Langtoft and released it at the gravel pits, at which point it gave me a rather sharp peck before swimming off - talk about gratitude!


Then it was back to the day job ...

Monday 25 April 2016

Cape Verde trip report

In March I spent a fortnight exploring the delightful Cape Verde archipelago with Neil Bostock and Dan Pointon. We were fortunate enough to clean up on all but one of the endemic species and forms - the only miss being Cape Verde Peregrine which, with no known sites, seems to require an immense amount of luck to connect with. Below you will find a comprehensive trip report including details of all these species plus the numerous other specialities and rarities that we encountered.

If you'd like the report in PDF format, or have any general questions about e.g. logistics, please email me.



Saturday 2 April 2016

A few thoughts on the Israeli Red-billed Teal

In early March I spent a long weekend in Israel, where the primary target was the long-staying Bateleur (which we saw). A real bonus was hearing of the continued presence of the Red-billed Teal in the northern Arava, 're-found' by visiting Finns Seppo and Hannu and seen shortly afterwards by visiting Brits Chris Bell et al. As we were at the Arava junction of Routes 40 & 90 when Chris' SMS came through on 5th, we bolted straight up to Hazeva and saw the bird pretty well in the strong mid-afternoon light, though it was very wary and was mainly seen in flight.

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

Since reading this it's become apparent that some members of the IRDC are seemingly not keen on accepting the bird as wild (words such as "dodgy" have been used by the committee and apparently the suspicion is that it will be rejected). More digging seems to throw up two primary reasons for this:
  1. The bird is behaving in sedentary fashion (i.e. it has been in Israel for two years and currently shows no signs of leaving)
  2. The bird has hybridised with a Mallard
To me, neither of these factors suggest captive/escaped origin and are certainly not detrimental to the idea that the Arava Red-billed Teal is a wild bird. Personally I think it is disconcerting that anyone could be dismissive of the bird based on the above two factors, though of course others don't share my view. Allow me to elaborate ...

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.

If you consider this in addition to the fact that Red-billed Teal is an abundant species in Africa with a massive range, the fact that none have been known in captivity in Israel for over a decade (though of course this does not discount the possibility of an escape from another country), that the bird is extremely wary and does not allow a close approach whatsoever (atypical behaviour for an escape), that Israel regularly attracts Afrotropical vagrants (including several long-stayers at present) and already has an accepted record of this species, I believe the evidence points towards this being a wild bird, despite the IRDC's reported reservations ...