Sunday 31 January 2010

Big Garden Birdwatch 2010

In the last few years, I stopped doing the Big Garden Birdwatch in my garden. The most likely outcome is a few Sparrows and one or two Blackbirds. A couple of Blue Tits if I am lucky. Fat balls and peanuts rot in my garden. Seeds are quickly taken from the feeders by the 10-12 strong local flock of Sparrows. If I put seeds on the bird table, Woodpigeons and Collared Doves stuff themselves in minutes. In summary, it is not a particularly enjoyable hour of birdwatching. Instead, I go to the local Wildlife Garden. Today it was sunny, but freezing, from 10:30 to 11:30. I had to keep walking to keep warm, and I wished I had taken a thermos of hot coffee with me. The total count was 15 species, better than the 12 last year.
Blue Tit singing
First year male blackbird (note the dark beak tip) sub-singing 
Dunnock
Birds
  1. Collared dove, pair flying together and singing. 
  2. Robin, 2 singing and chasing. One feeds on fat balls. Other feeds jumping on the iced pond. 
  3. Mistle thrush singing. 
  4. Great tit, 4 feeding in fat balls. 
  5. Blackbird, 4. An immature subsinging in the hazel bushes. 
  6. Goldfinch, pair, singing. 
  7. Chaffinch, male and female (2) 
  8. Woodpigeon, 1 
  9. Dunnock, pair, subsinging (10:38), wing flicking. 
  10. Greenfinch, 2 
  11. Coal tit feeder. 
  12. Blue tit, 3 
  13. Wren, 1st song of year. 
  14. Crow 2 
  15. Redwing 1.

Friday 29 January 2010

January Chorus

There are a surprisingly high number of bird species that start singing in January. A handful of species can pretty much sing all through the winter: Robins, Collared Doves, Woodpigeons and, surprisingly, Great Tits and Blue Tits. Some mild winters the Song Thrush will join them. Although the days are still cold and short, light levels are increasing by the day and this set birds into 'get ready for breeding' mood. One after the other birds join the chorus.
 In the last two weeks, Coal Tits, Song Thrushes, Stock Doves, Starlings (above), Dunnocks, Goldfinches and Chaffinches have, ones boldly, others more tentatively, taken positions and started to practice their singing. Even Sparrows sitting under the eaves have been doing their chirping.
Robin singing
Song Thrush

Thursday 28 January 2010

Spot us

I watched is a local flock of Redwing in a wooded area with clearings. I counted 12, feeding together on the ground, but keeping some distance in a loose flock. They behave very differently to Blackbirds, more wary and watchful, ready to fly silently up to the trees if they are disturbed. One of the birds was feeding amongst leaves, it had dug itself into a hole and enthusiastically pecked leaves aside looking for invertebrates - in very much Blackbird style. Redwings are so cryptic, even when sitting on grass they can pass for a fallen leaf, it's only when you stop and watch that their sudden movements make then apparent. Then you spot not only one, but the ground comes alive revealing the whole flock of Redwings.
Can you see the Redwing?

Friday 22 January 2010

Singing in the rain

If there is a group of birds who love bad weather, that's the thrushes. I guess there is a plentiful supply of earthworms in wet soil and they have a full stomach and a lot of time on their wings. It's been raining non-stop all day. This morning, a Blackbird sang softly from a tree. And, after the whole wet day, a Song Thrush joyfully delivered his repeated bold phrases on top of a bare tree this evening. Yesterday I heard the first song of the Song Thrush of the year. Today, two individuals sang from their prominent posts about one mile apart.

Despite the awful weather, the first signs of spring are here with us!

Sunday 17 January 2010

Making the best of bad weather

Birds have a range of behaviours to cope with the cold. Many - Swallows, Cuckoo, many warblers - avoid it altogether by migrating to warmer latitudes well ahead of winter, these are birds exploiting resources that are virtually non-existing in the winter such as caterpillars or flying insects. Others undergo more regional migrations, often depending on the local conditions. Here, surprisingly, there are many British species, which move south to the continent, and at the same time come to the UK from colder areas like Fennoscandia, these would include the Robin or the Blackcap. Yet another group of species simply change their habitat preferences. Some species that are found in mountain areas move down to the plains in the winter, species that feed on freshwater lakes and ponds in the summer move to the coast, where water does not freeze in the winter (Grebes and Kingfishers do this). There are a fourth group of species which change their food habits with cold weather. The Blackbird and other thrushes switch to feeding on berries when the ground is too hard to hunt for earthworms. I probably haven't exhausted the options and several of them are not mutually exclusive. For example, the Swift, a summer migrant from Africa, also undergoes substantial regional migrations in avoidance of poor weather. In addition, some of these options are only taken depending on the local conditions. The Waxwing's irruptions, when birds normally inhabitants of northern Europe, reach the UK and western Europe, happen in response to poor berry crops in the rowan of their native forests, and then to happen at irregular intervals. The last one of such invasions happened during the winter of 2008-2009.
  In the last few days, I have noticed couple of species which I don't see very often within the city have become more common. One of them is the Pied Wagtail, the other the Redwing. The first one belong to the  habitat switchers, the Pied Wagtail is most often found in gardens and towns during the winter. With its constant tail bobbing and its frantic running and direction-changing motion in chase of minute insects and bugs, to get a decent photo in the gloomy dark days we've had lately is a challenge. The Redwings, which migrate into the UK in the winter from northern Europe, feed on grassy areas - or berries - in loose flocks, they are quite wary and the photos are also not good.

Two Redwings

Sunday 10 January 2010

Collared Doves, the great colonisers

The thaw is quickly underway but there is still thick snow over the garden. I look out and there is a couple of Collared Doves resting on the apple tree. One of them, after carefully looking around jumps to the bird table to eat. The Collared Dove is a classic example of a species undergoing a range expansion. Although this expansion was achieved naturally, availability of grain due to agriculture undoubtedly played a role in facilitating it and in this species is strongly associated to cities, towns and agricultural land, and can be considered a human commensal species. Its original range was apparently India; by the sixteenth century it had reached Turkey and then, during the twentieth century, a rapid European invasion took place up to the point that now it has virtually colonized available areas over the whole continent. It is nowadays such a common urban bird that it is hard to believe that in the UK, the Collared Dove was first recorded breeding in Norfolk in 1955 (according to the British Trust for Ornithology the population estimate is over half a million pairs).

Reference: Hengeveld R. (1988) Mechanisms of biological invasions. Journal of Biogeography, 15: 819-828.

Friday 8 January 2010

Snow

A couple of crows searching for food in a patch of clear ground. The photo, illustrating bird behaviour in the current cold spell, was taken yesterday in the University grounds. Today the RSPB news release stated dramatically "Icy blast set to be millenium's greatest wildlife disaster". I wonder if they realised we are already in the new millennium (just 10 years into it!) and that climate warming was supposed to be THE wildlife disaster as far as we know anyway. I can entertain some theoretically possible, much more serious wildlife disasters: we could be stricken by an earth destroying meteorite and the Amazon might disappear entirely within the next 900 years). Climatic fluctuations, such as a spell of freezing, snowing conditions are natural phenomena which have shaped organisms behaviour for a long time. We cannot attempt to control this, as much as I am saddened by any bird losses due to cold weather, this is unavoidable and I am not sure that I would try and avoid it. Many animals are prepared for this, for example aquatic birds might undergo short migrations to the coast, where water is not frozen. Much as I appreciate that people are concerned about some endangered species that have recently been coached after much effort, to flourish (such as the Bittern), things can strech a bit too far. Central heated feeding stations? I don't think so.