Tuesday, 21 January 2014

The life of a garden bird...

Its the RSPB's Big Garden Birdwatch this weekend (25-26th of January) where everyone in Britain is encouraged to spend an hour counting the birds that are visiting their gardens or local green areas.  This can provide a large amount of information about the abundance and distribution of bird species.  This information can be used to assess current conservation efforts for species and/or highlight other species that may need help.  For example, the last birdwatch highlighted a decline in both starlings and house sparrows which promoted research into the reasons for this decline to enable conservationists to employ strategies to boost numbers.

House sparrow
'Garden birds' are not always appreciated as the most interesting of species so this birdwatch may not be an appealing activity to some people.  However, from personal experience I have noticed that these birds form a community and have their own hierarchy when it comes to access to bird feeders that is fascinating to watch.  Further research into this has indicated that much of this hierarchy is decided by size as you would expect.  For instance, the little coal tit is often surpassed by blue and great tits which themselves are out competed by nuthatches and greenfinches.  All of these birds give way to woodpeckers and if a pigeon shows up it is almost guaranteed to have the feeder all to themselves.

In addition, there is also competition within species as not all birds are of an equal status.  One of the ways that birds often judge the status of another is through visual displays as birds have four types of colour receptors which means they can see outside our visual range, e.g. UV light.  For instance, dominance in males is often indicated by the brightness of their plumage, such as the yellow on great tits chest or the orange of a blackbird's beak.  In summary, the bigger and brighter you are in this bird world, the more likely you are to get fed.  However, this may not always be the case and this can only be found out my watching these birds so I hope this is extra incentive for everyone to get involved in this birdwatch!

See this heirarchy in action in this video clip:

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