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| F.tinnunculus canariensis |
There is a reasonable diverse set of raptors in the islands,
both residents and visitors, but there are no endemic species (at least today).
There are however many endemic subspecies which are slightly different to the
mainland forms found nearby in Europe and North Africa, some restricted to only
a few islands and others also found on other islands in Macaronesia.
The commonest raptor we saw were two of the local races of
Common Kestrel, Falco tinnunculus. On Tenerife and La Gomera we had many good
views of F.t.canariensis, while on Fuerteventura we had F.t.dacotiae. The
Tenerife subspecies is darker and with heavier spotting than the nominate we
have in the UK, but in truth this is hard to recognise without birds to
compare, and the difference in light also means they look paler than they would
otherwise. The Fuerteventura form is quite pale looking as is common with
desert forms. Presumably they feed largely on lizards and small birds, as the
lack of diurnal rodents in the native fauna restricts their food supply. It
will be interesting to see what the arrival of the Barbary Ground Squirrel on
Fuerteventura will have on the resident subspecies, as they are pretty much
ideal kestrel size meals. |
| Barbary Falcon |
The other falcon we saw was a few brief views of the Barbary
Falcon, F.pelegrinoides. Like their close relative the Peregrine, they are
amazingly agile and fast in flight, and are presumably a major predator of the
larger birds found around the island. One other falcon, Eleanora’s Falcon,
breeds on the islands as a summer visitor, but it was too early in the year for
them to be seen.
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| Osprey |
We had good views of a soaring Osprey, Pandion haliaetus.
There are still one or two pairs nesting in the islands, but the ones usually
seen are migrants passing through on their way north. With no natural
well-stocked lakes, Ospreys are restricted to fishing in the sea, and I suspect
that good fishing sites are probably full of bathing tourists these days.
The other common raptor seen was the Canary race of Common
Buzzard, Buteo buteo insularum. Buzzards are pretty generalist in their diet,
so I suspect that humans have not made much difference from their point of view
– no doubt they formerly preyed on the giant lizards, but I would be very
surprised if they have not switched to rabbits these days. We also saw a single individual of the local race
of Sparrowhawk, Accipiter nisus granti, which also breeds on Madeira. There are
no Goshawks on the islands today, but subfossil bones have been found,
suggesting they are a casualty of the deforestation following human arrival,
especially after the Spanish conquest. |
| Egyptian Vulture |
The largest raptor we were fortunate enough to see were two
of the local subspecies of Egyptian Vulture, Neophron percnopterus majorensis.
There are probably under 300 individuals of this subspecies left, possibly much
fewer, and there is a support system being developed supplying carcases at “vulture
restaurants”. There is an issue with Egyptian Vultures however – namely what
did they live on before humans arrived with their livestock? With no native
large mammals to supply food, and pre-human vultures would have had to survive
on monk seal colonies (if any), seabird chicks, and the occasional beached
whale. This seems thin pickings for a viable population, and it is quite likely
that they only began breeding regularly on the islands after humans colonised
them, and the differences from the mainland birds is a result of founder
effects. For more on this see this paper: http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3009672/
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| Long-Eared Owl |
We did not see any owls on the trip, but there are also two
owl species on the islands. The more widespread is a local race of the
Long-eared Owl, Asio otus canariensis. This is found on most of the islands,
and these days preys heavily on rats, but also still takes its pre-human prey
of birds and sometimes reptiles. Barn Owls also breed on the islands – there is
a resident race Tyto alba gracilirostris on Fuerteventura and Lanzarote, but
this is very rare and there are probably only a few hundred pairs on the two
islands. In the past it doubtless preyed on the Lava Mouse and Dune Shearwater,
along with large insects and geckos, but these days other prey items are
available. The nominate race that we have in the UK is found on the western
islands and may be a recent immigrant as well.
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| Barn Owl |
Next time, I will cover the remaining non-passerines,
including three very important endemics – the Laurel and Bolles pigeons, and Plain Swift
(all images from Wikipedia)
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