If you watched "BBC Springwatch" last Thursday, the 31st May, you will have seen the launch of a British Trust for Ornithology (BTO) Survey called the "Big Garden Weigh-in". The survey will look at the structure of garden bird communities and how they differ depending on location, size of garden and local habitat. The survey will form part of a large area of research, including the BTO Garden Bird Watch and Garden Bird Feeding Survey, to examine how garden bird communities vary throughout the British Isles in relation to habitat and over a period of time.
The survey will take place between 31st May and 5th June and anyone can participate (just visit www.bto.org for more details). All you need to do is watch your garden and count the maximum number of each of 60 species seen within an hour on one of these days.
After entering your records a bird biomass score for your garden is calculated and then you can find out how this compares with other UK gardens.
Some of the initial findings will be reported on "Springwatch" and eventually a peer-reviewed scientific paper will be prepared for publication.
I watched my garden for an hour today and recorded the birds and here are the results: (you will see the larger the birds are that visit the higher the biomass!). (Although I am not particularly happy at seeing magpies, carrion crows or great spotted woodpeckers in the garden when bird are nesting, I would have liked to see them during this particular hour to boost my garden biomass a bit!)
Feral Pigeon x 2 weighing 289g each = 578g
Wood Pigeon x 4 weighing 403g each = 1,612 g
Blue Tits x 2 weighing 11g each = 22g
Great Tits x 2 weighing 18g each = 36g
Coal Tit x 1 weighing 9g each = 9g
Blackbird x 2 weighing 95g each = 190g
Robin x 2 weighing 18g each = 36g
Dunnocks x 2 weighing 20g each = 40g
House Sparrows x 6 weighing 26g each = 156g
Chaffinches x 2 weighing 21g each = 42g
Greenfinch x 1 weighing 27g each = 27g
Goldfinches x 2 weighing 15g each = 30g
Total biomass of the garden for all bird species = 2,778g.
A nice little bar graph is produced as well showing the above results
Compared to the rest of the UK
my bird biomass at this moment in time is 57th out of 115 bird biomass submissions from the West Midlands region and 731st out of 1,295 submissions from the entire British Isles.
I found the biomass results very interesting and an added bonus was that in watching garden closely for an hour I saw my first house sparrow and great tit fledglings!
If you decide to take part I would love to hear how you get on.