Breeding plumage male Little Bustard in the open - NB:This never happens |
There are three species of Bustard that breed in Europe and
I am glad to be able to say I have seen all three. Admittedly the Houbara
Bustard only counts if you include the Canary Islands in Europe, when in terms
of their location and endemic species they are more accurately part of North
Africa, but they belong to Spain so I am going with it. This year I have had
good views of the mainland species, Little and Great Bustard, in Portugal this
spring and again in autumn in Spain.
As a group, the vast majority of bustards are African.
Outside Africa a given region usually only has one or two species in the same
area, and telling them apart is straightforward. They are all birds of treeless
areas, either grassland, savannah with some bushes, or desert, and they all as
far as is known have similar diets of plant materials, insects, and for the
larger species reptiles and small mammals. They nest on the ground and adult
males are almost invariably larger than females, and have spectacular courtship
displays, often in leks.
Little bustard female - visible in autumn fields |
Seeing Little Bustard Tetrax tetrax during the breeding
season is usually rather difficult. At that time they are spending most of
their time concealed in grass as high as their heads. Males display in a
dispersed lek by leaping up into the air to display their black and white necks
while uttering the distinctive call that gives them their French name of
Outarde canepetiere – roughly translated the farting bustard. I saw them this
spring in Portugal on their breeding grounds on the edge of the great Iberian
steppe. By November they have finished breeding and congregate in large flocks
on cleared fields, and we found a flock of at least 150 birds.
As with many birds that are dependent on low intensity
grazing and traditional farming methods, Little Bustards have been heavily
affected by changes in farming practise, and the population in western Europe
is declining. In Spain they are resident, but further north they are migrants,
wintering in Spain and North Africa. In France there is a reintroduction
project aiming to boost the population with captive bred birds. To the east
there is another population which ranges from the Balkans east through Turkey,
Russia and Kazakhstan which at least at present seems to be doing rather
better, but overall the IUCN lists the species as Near Threatened.
Male Great Bustard |
The other bustard species we found are one of the
characteristic species of Eurasian steppe habitats, the Great Bustard Otis
tarda. I have seen these several times before, but they are always an amazing
sight, especially the gigantic males, which at over 1m tall and a weight of
18kg are among the heaviest of flying birds. As with Little Bustards, the
population is declining as a result of changes in agricultural practise, and as
a result of the birds’ giant size they need large areas of suitable habitat
when breeding. An interesting feature of the species is that although they are
omnivorous, the males especially show a deliberate preference for poisonous
blister beetles during the breeding season. The beetles contain cantharidin, a
highly toxic compound which has medicinal properties. However, it has also been
used (in very small quantities) as an aphrodisiac by humans, and it has been
suggested that that may be part of the reasons the bustards use it as well. I
expect debate on this may go on for some time.
Although matters may have stabilized in Spain the eastern
population is declining rapidly and consequently it is currently listed as
Vulnerable by the IUCN. There have been some attempts at reintroductions,
notably to Salisbury Plain in the UK, but although there have been a few chicks
raised at present it looks rather unlikely that a viable population will be
established.
(Images from Wikipedia)
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