Bad weather results in disastrous breeding season at Langstone Harbour
29 August 2012
The unseasonal wet and cold weather during the breeding season resulted in Langstone Harbour’s birds producing very few young this year says the RSPB.
At the start of the breeding season, there were nearly 5,000 gull and tern nests on the harbour islands and at the Hayling Oysterbeds, including 40 nests of the rare and endangered little tern. Egg-laying started in mid-April, and all of these birds typically lay three eggs at the start of the season.
By the end of May, many of the nests at the Oysterbeds held small chicks, while the nests on the harbour islands contained eggs that were due to hatch in a matter of days. Some of these nests belonged to birds that had already re-laid eggs after losing their first clutch due to tidal flooding in early May.
Then during the first week of June, all of the high tides surged to dangerously high levels, resulting in many nests being flooded, particularly those of the little and common terns.
Chris Cockburn, RSPB Warden at Langstone Harbour, said: “In the early hours of 08 June, the tide level was exceptionally high and this coincided with a prolonged period of gale force winds. This resulted in waves and spray sweeping over much of the nesting areas.
“Thousands of chicks were still at the fluffy downy stage, and not being waterproof they sadly drowned or died of hypothermia. This signalled the end of the breeding season for many of the birds because the adults cannot get back into breeding condition once their eggs have hatched.
“However, when eggs rather than chicks are lost, the adults will sometimes re-lay and try again if they can get back into breeding condition quick enough.”
More damaging tidal surges and bad weather in July resulted in no terns and only 14 gull chicks fledging from the harbour islands.
The RSPB has recently been awarded funding from Europe for work that will help protect and conserve the critically endangered little tern populations at the RSPB’s Langstone Harbour reserve.
The work at Langstone Harbour, which is due to start next year, involves protecting current little tern nests, as well as increasing nesting areas by spreading additional shingle.
The grant from EU’s Interreg funding stream is part of a large cross-channel partnership, which will work towards building a protected area network across the English Channel.
There was also some good news from the Hayling Oysterbeds, where over 60 black-headed gull chicks fledged from the original nesting attempts.
Chris Cockburn added: “In addition to the chicks which survived the first breeding attempts, approximately 25 black-headed gulls and 50 common terns re-laid eggs and, despite a few of the nests being flooded by surging tides in August, many of these birds now have chicks that we hope will fledge.
“Some of the common tern chicks are only a few weeks old, so it is likely to be well into September before the breeding season finishes – normally, the breeding season ends before August.”
At weekends, RSPB volunteers are at the Hayling Oysterbeds with telescopes for people to have close views of the birds.
· The harbour islands are part of the RSPB Langstone Harbour Nature Reserve.
· The RSPB reserve occupies one third of the Langstone Harbour tidal estuary and consists mostly of intertidal mud but includes five small islands composed of saltmarsh and shingle ridges.
· Apart from a landing area for recreational boat users on one of the islands, access to the reserve is restricted, thereby allowing birds to breed, feed and roost in an undisturbed state and the fragile habitats, with their specialised fauna, to develop naturally.
· The reserve can be viewed from public rights of way around Langstone Harbour. For more information got to: www.rspb.org.uk/langstoneharbour
· The Hayling Oysterbeds are part of the West Hayling LNR that is owned by Havant BC and jointly managed by the RSPB.