Assistant Warden Ash Radford writes about this year's breeding season at Woolston Eyes. It’s been a year of ups and downs at Woolston with lots to be positive about in terms of breeding success. Read on to find out how our birds did this year and discover what makes Woolston eyes so special and why the RSPB is working with the Woolston Eyes Conservation Group to help manage their reserve.
For those who don’t know the site, Woolston Eyes Nature Reserve is located to the east of Warrington between the River Mersey and the Manchester Ship Canal. The reserve consists of four large lagoons which have been used for depositing natural material dredged from the Manchester Ship Canal, extending from Latchford Locks eastwards underneath the M6 Thelwall Viaduct. The four dredging 'beds' cover over 260 hectares of land and now boast a mixture of habitats including shallow pools, reedbed, mature woodland, willow scrub and wildflower meadow.
Regular counts of 500 gadwall have been recorded building on site towards the end of summer. Nationally important numbers are flocks over 400 so this is a significant count occurring at Woolston. Numbers can reach up to 600 in late August which reaches internationally important significant. With counts of nearly 900 in the past, these high numbers of gadwall in late summer have been occurring for the last six years. Breeding wildfowl on the reserve included eight to 10 pairs of gadwall, eight pairs of tufted duck and 8 pairs of pochard. May saw regular sightings of male garganey, though no breeding on site was confirmed.
Drake Garganey (Dave Spencer)
Our black-headed gulls had a poor year despite there being good numbers around (250 pairs) across the site with many pairs occurring on the shell island, brash islands and new raft. We also saw them using the side rafts which were intended for black-necked grebes. In early June, a majority of the gull colony deserted due to predation. This resulted in around 25-30 fledged juveniles, down significantly from last year’s 135. We hope to use cameras to monitor nests more closely next year and electric fences on the scrape will hopefully protect the gulls and lapwings which choose to nest there.
Black-headed gulls in new nesting areas (Dave Spencer)
A silver lining to the cloud that was the breeding success of our black-headed gulls was the success of our star species, the black-necked grebe. We observed 10 pairs producing at least 10 broods on the reserve, up from last year’s 9 pairs. There was a maximum count of 16 adults and 19 juveniles, of which we believe 17 juveniles managed to fledge the reserve -- a fantastic success up from last year’s eight fledged young. On 13 June, two pairs had been observed displaying and mating; this late activity could indicate the production of second broods. These dredging areas have become famous for their numbers of black-necked grebe which have bred across them. Black-necked grebes arrived on the reserve in the mid-1980s, with breeding first proven in 1987. Unusual for the species, black-necked grebes remained faithful to the breeding site at Woolston with numbers building up and eventually peaking at 32 birds in 2008. Since then, numbers have steadily fallen, with breeding numbers now averaging around 8-10 pairs. These numbers are still significant, with UK breeding numbers averaging around 50-60 pairs, meaning Woolston Eyes has been home to up to 40% of the entire UK population at times in the reserve's history.
Black-necked grebe (David Bowman)
Woolston remains the premier site for breeding grebes with 17 pairs of little grebes across the site, some of the best numbers for the species in Cheshire. Meanwhile, five pairs of great crested grebes produced three broods.
Great crested grebe (David Bowman)
Away from the water, 25 pairs of willow tits were observed across all four beds of Woolston eyes, slightly down from last year’s 30 pairs. Willow tits are one of our fastest declining birds, having lost around 88% of the UK population since 1970. Woolston’s population contributes to the stronghold for the species in North West England, with sites around Wigan, St Helens, Warrington and Chorley supporting more than 10% of the UK willow tit population.
Grasshopper warblers were noticeably absent with brief sightings on Number 3 bed but no observed reeling on a consistent basis from any areas. Juveniles have been caught by ringers on site, possibly indicating that pairs bred unobserved close by, but it was a poor year down from a four to five pair average on site.
Little ringed plovers had a good year with two, possibly three, pairs taking advantage of the tipping area on Number 1 bed and successfully raising young with fledglings seen frequently in front of the John Morgan hide in late June.
Other successes include a pair of peregrines nesting on the M6 viaduct which fledged two, possibly three, young this year. Regular sightings of ravens occur at Woolston throughout the year with reports this year from nearby Lymm of newly fledged young confirming local breeding success.
Towards the end of July, swifts were often seen around the nestboxes we placed on the Morgan hide last year. They were heard knocking on the nest box sides, which could be a sign of birds prospecting for next year’s nesting sites, and this would be a new breeding bird for Woolston Eyes.
Swift at John Morgan nest boxes (Dave Bowman)
Please note that Woolston Eyes Nature Reserve is not an RSPB reserve, so does not qualify for free access to RSPB members. If you wish to visit the reserve, a permit and key is required from the Woolston Eyes Conservation Group; further information, sightings and permit requests can be found at their website.
Management work on the reserve is extensive and we rely heavily on the help of volunteers on the site. If you might be interested in getting involved, contact our assistant warden Ash Radford via email at ashley.radford@rspb.org.uk