Saturday, 12 April 2014

Quest for the Wild Canary 8: Houbara Bustard and Waders

Female Houbara Bustard, Fuerteventura
One of the key target species of any birding trip to the eastern Canary islands is the local race of Houbara Bustard Chlamydotis undulata fuerteventurae. With a total estimated population of around 500 individuals, possibly less, it is also one of the most endangered bird taxa on the islands, and indeed the world. In truth, the division between the island birds and those on the mainland, nominate undulata, is slight – mainland birds are slightly larger and paler. More significant is the split between the birds in North Africa and those in western Asia – these have now been split as McQueens Bustard on the basis of different courtship  displays. As February is the start of the breeding season, seeing the amazing courtship display of the male was a key goal, and we were fortunate enough to see several displaying males on our trip.

Male Houbara, Fuerteventura
Hourbara are highly terrestrial – they can fly well but almost invariably prefer to run or freeze when they feel threatened. By viewing from the van, we managed to get amazing views of several individuals close to the car, and I got some reasonable photos as you can see from this post.
Houbara are omnivorous feeders, taking plants, insects, and probably small lizards as well, but the one we saw feeding was pecking at plants. It was probably an adult male judging by the black on the neck. The photo I got was not especially good, but later I got much better photos of a female that was close to the road as well, and which you can see at the top of this post. The main threats to Houbara are their being a prime target species for Arab falconers, combined with habitat degradation from overgrazing, desertification, and road construction, especially on Fuerteventura. The current population is divided more or less equally between Fuerteventura and Lanzarote, with 2 – 300 adults on each according to most surveys.

The display of the male Houbara has to be seen to be believed. We were not close enough to get photos, but they are usually fairly visible when displaying – they tend to use ridges so that females can see them for some distance. They also avoid cluttered landscapes – running around in a circle of figure of eight pattern they can thus avoid running in to obstacles while their vision is obscured. For a video of a displaying Houbara, see here:

Cream-Coloured Courser
Houbaras share their habitat with a rather unusual wader, the Cream-Coloured Courser Cursorius cursor. Waders are so associated with wetlands that one running around in a desert looks really strange. The photo is from Wikipedia, and the exact shade they appear depends on the light – the ones we observed seemed much paler, fully justifying their name. Another dry country wader that I got good photos of were a pair of the Fuerteventura race of Stone Curlew, Burhinus oedicnemus insularum. There is another subspecies on Tenerife and Gomera, distinctus, but this is now extremely rare, probably as a result of tourist development of the dry coastal strip where their only habitat is found.

Fuerteventura Stone Curlew, insularum
A variety of more conventional waders were also seen in wetland areas and beside the sea. Sanderling are long distance migrants so their appearance on the shore is unexceptional, but we were also lucky enough to find a small flock of Kentish Plover Charadrius alexandrinus.
Kentish Plover
Sadly, one species that no one will ever find is the no extinct Canary Island Oystercatcher Haematopus meadewoldi, which died out in the first half of the 20th century. The cause of its extinction is unclear, as it had survived alongside humans for well over 2,000 years. On the whole, oystercatchers (there are many species worldwide) manage to get alongside people fairly well, but it is perhaps significant that the rarest surviving oystercatcher is also restricted to an island group, in this case the Chatham Islands near New Zealand. Oystercatchers come in two basic colour patterns – white bellied species like the Eurasian Oystercatcher and all-black species. It may be a result of limited data, but from my reading it seems that the all-black species are more associated with rocky coasts, while white-bellied species are associated with habitats with sand or mud. How the Canary Oystercatcher was related to the living forms is not clear – there appear to have been no DNA studies of oystercatcher relationships – but in life it was apparently almost identical to the African Black Oystercatcher show here. Presumably the African species at some point had a wider range, as today it is confined to South Africa, and this gave rise to the Canary species.

African Black Oystercatcher
Next time, I will cover the raptors and owls of the islands, which also have an interesting history

(Bustards and Stone Curlew are my photos, rest from Wikipedia)


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