Thursday, September 23, 2010

A mystery solved.

How do cuckoos steal a march on the eggs of their host in order to hatch first and then evict all of their competitors? Researchers at Sheffield University think they have found the answer (Published September 22, 2010 in the journal Proceedings of the Royal Society of London, Series B).
They believe that, in comparision to other birds, female Cuckoos hold on to their eggs for a further 24 hours before they lay them. This gives them the added advantage of being incubated at 40dC rather than the 36dC they would experience in the nest. This additional warm for 24hours, in terms of development, gives them a massive 31 hours growth difference compared to the eggs in the nest - and in developing eggs this time difference on development is huge.
As a result, this means that the cuckoo will hatch at least 24 hours, if not more, before the other eggs allowing it to perform its dirty deeds before the others have a chance.
Image from RXWildlife Sightings.

Tuesday, September 21, 2010

Antibiotic resistant bacteria found in gulls

Portuguese researchers analysing droppings from Caspian Gulls found that one in ten of the birds carried antibiotic resistant bacteria. Given that these birds are wild the only way that they could have come into contact with antibiotics would have been via eating human scraps (off rubbish tips and the like).
The concern now is that these birds could act as reservoirs and transporters of resistant bacteria to other areas, and that bacteria from their droppings could re-enter the food-chain causing an increase in the spread of resistant bacteria.
See: http://www.bbc.co.uk/news/health-11374536

CE60645

The oldest recorded British Arctic Tern - 30years 2months 23days (at least). Ringed as a chick on the Farne Islands on 28th June 1980 and recaptured this summer. Not a world record however, that is held by a US Arctic Tern that lived for 34 years.
See: http://www.bbc.co.uk/news/science-environment-11375618

Friday, September 17, 2010

Garden Bird Feeding Survey

The Garden Bird Feeding Survey, at 250 geographically selected gardens, has now been running since 1970. During that time it has plotted many changes in bird feeding activity so now, at 40 years of age, it seemed prudent to have a fresh look at the data collected.
Surprisingly, the number of feeding BlueTits in winter has dropped from 5.3 (average count per garden per week) to 3.1 This doesn't necessarily on its own indicate that Blue Tit numbers are dropping, just that they are not feeding in gardens. However, other surveys do show that numbers are decreasing so the number of birds feeding in gardens actually supports this trend.


GBFS data, by the same token, also supports the precipitous decline in Starlings and Song Thrush (down 75%) and House Sparrow (down 70%). On the other hand it also indicates good news - Goldfinch up 25 fold, Long-tailed Tit tenfold and Great Spotted Woodpecker fourfold.

Shotton Tern Colony

For the second year running the colony of Common Terns at Shotton failed to breed. This is disturbing news given that not so long ago they hatched over 800 chicks in one season. Concerned at this change of events a meeting of interested parties was convened to try and understand what had happened, what was potentially happening, and whether anything that could be done to reverse this non-breeding could be actioned.
At the end of August representatives from Merseyside Ringing Group (who tend and ring the terns), Corus (on whose land the terns nest), the Countryside Commission for Wales (statutory government agency), RSPB, Lancashire Wildlife Trust and Environment Agency Wales all met to discuss the colony. The notes and minutes of this meeting can be found at:
http://www.davidnorman.org.uk/MRG/shotton_common_terns.htm
Please feel free to read and comment. One request from the meeting was:
"We would be particularly interested to know if anyone has information on sandeels in the Dee estuary and if there is any objective assessment of where the terns preferred to feed - we've all watched them but we haven't really analysed their movements".