Tuesday, 12 June 2012

15 Years, NOT moving SWIFTLY along.


The Swallow, Swift and House Martin are beautiful, agile birds that are similar. There are, however, individual features that tell them apart.



Swallows, swifts, and house martins are all summer visitors migrating to and from southern Africa. 
In the United Kingdom it is possible to observe these birds, usually in flight, and to hear them trilling and calling to each other.
Traditionally the return of the swallows has always been associated with the coming of Spring. 

Because these three birds are alike, they are often mistaken for each other. However, with practise and careful observation it is possible to distinguish between them fairly easily.

Some Interesting Facts About the House Martin

  • House martins are often mistaken for swallows
  • House martins are known to be attracted to hot air balloons and can soar above the rising current of warm air.
  • The Latin name for this breed is Delichon urbica.
  • House martins lay their eggs between May and August, laying, on average, 4 eggs.
  • These birds build their nests under the eaves of houses.
  • House martins have a blue-black upper body with a metallic sheen to their feathers.


Some Interesting Facts About the Swallow

  • Swallows are thought, by some communities, to bring good luck. This is why farmers do not destroy their nests and birds can re-use them for many years.
  • The scientific name for swallows is Hirundo rustica.
  • Swallows are agile flyer's and seldom seen near the ground.
  • Unlike swifts and house martins, the swallow has a deeply forked tail which can measure 8cm in length.
  • Swallows also have a beautiful red throat.
  • Fewer swallows are coming to the UK than ever before, but the reason for this is unknown.
  • You can often see swallows perching on wires, especially around migration time, when they gather in flocks.

Some Interesting Facts About the Swift

  • Swifts are often seen chasing each other around in the sky.
  • This bird has a unique "crescent" or "boomerang" shape when in flight, which is more pronounced than in swallows and house martins.
  • Breeding is the only time swifts stop flying - they even eat in flight by catching insects and sleep in the air.
  • The swift population in the UK has decreased over recent years.
  • Swifts build their nests on an almost vertical surface using their saliva as a "glue".
  • The Latin name for this breed is Apus apus.

Spend some time looking at the skies to see if you can spot the differences between the Swallow, House martin and Swift! 
If you look carefully you should be able to see the nests of at least one of these birds.

However my specific interest for the past 15 years has been studying the Swift for the British Society Ornithologists (BSO).

The swifts are a family, Apodidae, of highly aerial birds. They are superficially similar to swallows, but are not closely related to passerine species at all; swifts are in the separate order of Apodiformes, which they share with hummingbirds.

The resemblances between swifts and swallows are due to convergent evolution, reflecting similar life styles based on catching insects in flight.

Swifts are a larger species and are amongst the fastest fliers in the animal kingdom, having been reported flying at up to 169 km/h and cruising at 5 to 14 metres per second (18–50 km/h, 11–31 mph).

In a single year the common swift can cover at least 200,000 km.

The taxonomy of the Swift is widely debated and in general complicated, with genus and species boundaries widely disputed.

Analysis of behaviour and vocalisations is complicated by common parallel evolution, while analyses of different morphological traits and of various DNA sequences have yielded equivocal and partly contradictory results.



All these things make this bird one of my personal favourite species on earth, to watch, listen to and study.

Apart from biological developmental interest of this bird, why is it relevant and important NOW?.

Well; findings show that the number of swifts breeding in Britain has declined considerably over the last 15 years.  
Much of this decline is caused by the loss of nesting sites due to building repairs or even simple re-pointing of brickwork, which means that swifts can no longer access traditional sites.

Gathering information about where swifts are nesting makes it easier to preserve this bird.  Existing nest places can be reinstated, new ones designed and built into eaves.  Swift nest boxes can also be installed. 

Without knowing nesting information and location, they will continue to be lost and so will the birds.



During 2011 in a regional part of Britain there had been 130 ‘Swift buildings’ identified
containing several hundred nests.

The network consists of about 30 people who have Swifts nesting in their property, or who look out for Swifts and their nests, and send in records.

Many councils have since been contacted and with the help other conservation organisations funding has been granted to provide churches with appropriate nesting boxes and council owned property to keep in mind that these birds use the buildings when it comes to repairs and redesign.



The future is bright for these magnificent birds if we can all take the time to listen, look and observe.

15 years ago I was studying 30 pairs of nesting swifts. 

2005 it was down by half. 

2009 I was observing six pairs of whom I believed to be the offspring from year before.

We installed nest boxes… 

2012 I am now observing 12 pairs of birds.

Whether these birds are birds which had originally moved on from the area as nesting places had declined and have now returned is yet to be confirmed. 

But it is an interesting outcome and positive outlook for the species IF we can work together.

If you hear or see these birds in your property please contact your local conservation group, ranger service or council as they can put you in contact with people who can advise the best way to preserve these birds for years to come.

G.

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