Atlantic Canary |
The canary is actually named for the Canary Islands, rather
than the other way around as you might think. The name originates from the
Latin name for the islands – Canariae Insulae “Island of Dogs” – a name
allegedly given to one of the islands by the Mauretanian king Juba II as a
result of the many large dogs found there, although it is possible that the
‘dogs’ were Monk Seals.
Picnic table birds! - La Lojas, Tenerife |
Whatever the origin of the name, it was applied to the local
species of Serin, Serinus canaria, which these days is referred to in the field
guides as Atlantic Canary to distinguish it from the several related species of
‘canary’ found in Africa. On our trip we got numerous good views of them on
Tenerife and La Gomera, although they also occur on some of the other islands.
They are not naturally found on Fuerteventura or Lanzarote, although a few
introduced pairs have been breeding on Fuerteventura for about 20 years in the
higher parts of the island – most of the eastern islands are too dry to provide
suitable habitat today. Incidentally, Atlantic Canaries are also found on
Madeira and the Azores, although I am not sure if they are native there or have
been introduced by people.
Lotus bethelotti |
Unlike many of the native species, Canaries have probably
benefited more than suffered from human settlement, despite the mass trapping a
few hundred years ago for the cage bird trade. Farmland and permanent water
sources for livestock mean more suitable habitat for an open-country specialist
in grass and other small seed. Other species have not been so fortunate – at
least three species of seed-eating passerine are known only from subfossil
remains on the islands. Two of them were local species of Greenfinch – Trias
Greenfinch Carduelis (Chloris) triasi on La Palma and the Slender-Billed
Greenfinch C. (Chloris) aurelioi from Tenerife. Tenerife was also home to the
third species, the Long-Legged Bunting Emberiza alcoveri. The bunting is
especially interesting as the size of the wings in the remains found indicate
that it was either flightless or very nearly so, which is unusual in
passerines, even island ones. There may have been other passerines as well, as
some of the plants seem to be adapted for bird pollination, and there are now
no specialist flower-feeders on the islands. Some of the living birds such as
the Canary Chiffchaff and other warblers apparently serve the function of
pollinators of these flowers, some of which are quite common as ornamentals –
for example Lotus berthelotti.
Fringilla teydea teydea, Tenerife |
For birders, the most famous of the native passerines though
is the famous Blue Chaffinch, Fringilla teydea. There are two subspecies known,
the nominate form on Tenerife and the now extremely rare F.teydea polatzeki on
Gran Canaria. Both subspecies are specialists of the Canary Pine forests found
on the upper slopes of the mountains, although they may move downhill in hard
weather. There large bills enable them to make use of the pine seeds. No other
island finch has this ability, and it is interesting that there never seem to
have been any crossbills on the islands, which are the usual pine seed eating
birds across most of the northern hemisphere. Judging by how hard they are to
see when feeding on the ground in the shade of the pine trees, the colour is actually
good camouflage. The Tenerife birds are actually doing quite well - reforestation is expanding their habitat and we found them very easily at La Lajas picnic site in the national park, where they were feeding on crumbs on the picnic tables along with the canaries. As we were there in February the breeding season had not yet started - this is usually around late May onwards. They only lay two eggs usually per nest, which suggests they do not face high post-fledging mortality compared to mainland chaffinches.
F.teydea - harder to spot than you would think |
The same blue colour is also found on the local races of the
Common Chaffinch, Fringilla coelebs. There are several subspecies on the
islands (the ones we saw on La Gomera were F.coelebs canariensis), but they all
differ from the subspecies we have in the UK by having more extensive blue
shading on the head and back. There may be a parallel with the various forms of
blue tit on the islands (see last post) – some genetic analysis indicates they are
sufficiently distinct to merit status as full species.
F.coelebs canariensis |
F.coelebs coelebs |
Another important finch species we saw, this time on
Fuerteventura, were Trumpeter Finches Rhodopechys (Bucanotes) githaginea. These
are also found across North Africa, and they are very distinctive with their
large pink beaks. Trumpeter finches are traditionally thought of as closely
related to the rosefinches Carpodacus, but they actually seem to group in
genetic analyses with the Asian Rosy-finch Leucosticte arctoa, and more
distantly with the bullfinches Pyrrhula. There are no native bullfinches on the
islands today, but they may have occurred in the past.
Rhodopechys githaginea |
Finches are still colonising the islands naturally today.
Greenfinches colonised around 50 years ago, and other species show up as
vagrants and might begin nesting in the future if conditions are right. Not
technically a finch, but at least a seed-eating passerine, Spanish Sparrow
Passer hispaniolensis colonised around 1830
and has spread to become the ‘standard’ sparrow in urban areas all over the
islands.
Passer hispaniolensis |
This brings my survey of the islands’ wildlife to a close.
Human influence has been a recurrent theme of this series, and a brief overview
of the history of the islands seems an appropriate way to finish it off next
time.
(most of the images are mine, with the exception of Common
Chaffinch, Trumpeter Finch and the plants, which are from Wikipedia)
No comments:
Post a Comment