Monday morning saw a brave team of staff and volunteers (not me I’m sorry to say) heading out whilst still dark and very cold to perform our monthly Wetland Bird Survey (WeBS). WeBS is a national scheme where wetlands throughout the country are surveyed once a month and the resulting species counts used to monitor population trends amongst our wetland birds.
This Monday, amongst the hundreds of wigeon, teal, pintail and shoveler in the Arun Valley we counted record numbers of black-tailed godwit. We’d had a hint that there might be a large number of godwits on the brooks from Steve Gale and his great blog http://northdownsandbeyond.blogspot.co.uk/ ; Steve had done a count of the godwits from a photo he had taken of the flock in flight and estimated in excess of 800. Monday’s count reached the 950 mark - our previous record, achieved last winter, was 550.
Data from the wetland bird survey has revealed the development of some new wintering concentrations in the UK – in East Anglia and in Sussex and we look to be part of that trend. The majority of these birds are an Icelandic race, returning to Iceland to breed each year. Despite the increase in over-wintering populations in Britain, overall breeding populations have declined and the black-tailed godwit is on the red list of birds of conservation concern.
One way that we’re learning more about the black-tailed godwits is through colour-ringing. Ringing studies enable monitoring of many aspects of birds’ lives including survival, breeding success, population size and migration patterns. The use of colour-rings allows individuals to be re-sighted without the need to catch them.
Colour-rings may be on the tibia (upper section of leg above the joint) or the tarsus (lower section of leg below the joint). Most black-tailed godwits will have two colour-rings on each tibia, but they may have more; including rings with a black X, rings with stripes or rings with a flag extension (denoted by f).
The black-tailed godwit study has uncovered a number of interesting things– for example, males and females of a pair winter on average around 1000km apart, but will arrive on their breeding territory within 2-3 days of one another.
How to read colour rings
The following colours are used for black-tailed godwits:
Ring combinations are read as left leg top, left leg bottom, right leg top, right leg bottom (leg position is always in accordance with the bird).
Try it out with this bird, photographed at Pulborough Brooks by one of our wardens David:
If you see any colour-ringed birds at Pulborough Brooks please report them to the Visitor Centre (and photograph if possible) and to Peter Potts of the Farlington Ringing Group petermpotts@gmail.com.
We have found a number of colour-ringed birds amongst the Pulborough Brooks flock and have been reporting the sightings and finding out more about our visitors. One bird known as ‘WY-YX’ was ringed 13 years ago and has been spotted here in December 2012, 2013 and 2015. As well as visiting Pulborough Brooks, this bird has been reported on the coast nearby at Farlington Marshes and at Langstone Harbour. Depending on conditions – the amount of floodwater and on temperatures it would seem that the godwits move between inland sites and the coast.
If you visit the reserve take a look in the hides for a full history of ‘WY-YX’
Whether you find any colour-ringed birds or not, the black-tailed godwits are fabulous birds to watch – they are restless and noisy, chattering away to one another whilst probing the mud in search of worms and other goodies. If disturbed and they frequently are here by the hunting peregrines their white under-parts catch the sun beautifully.
Photo from volunteer Phil Thornton
Very interesting article Anna.