Thursday 12 July 2018

CURLEW BOUNCE BACK IN CONTROVERSIAL RAVEN CONTROL AREA OF STRATHBRAAN

*The SGA is delighted to hear news of wader success in Strathbraan in 2018. The SGA is providing technical support to the SGA members within the control area.



Land managers in Strathbraan are predicting an excellent year for endangered waders following the granting of measures to protect vulnerable chicks from predation.
Farmers and gamekeepers were granted a license from Scottish Natural Heritage to control juvenile flocks of predatory ravens in a bid to protect birds such as Curlew; now classed the UK’s most urgent conservation priority.
Breeding Curlew populations have crashed by half in the UK in 25 years and, across Europe, the estimated breeding success per pair is only 0.34 chicks per nest- not enough to prevent further declines.*
The management trial, which allowed up to 69 ravens to be taken this year, was controversial in some quarters, despite frequent and widely accepted observations of chick predation by marauding raven flocks.
Anecdotal reports on the ground suggest the additional protection afforded to the wader chicks has already paid dividends this year.
Strathbraan has seen the rare and welcome sight of nests fledging four Curlew chicks this year, leading to optimism that productivity counts will demonstrate much needed relief for the embattled birds.
Encouragingly, raven predation pressure seems to have been low this year, with fewer than half permitted under the license, having been taken.
“There is a definite upsurge this year in the waders,” said local gamekeeper Ronnie Kippen, whose ground falls within the licensed area. “We have barely seen a pair of Curlew without chicks.
“Oystercatchers are roughly the same as we observe but Curlew and Lapwing have made a big shift. The hens were in good breeding condition but the chicks have been much better protected.
“The ravens have got clever, which we anticipated, plus they have not been able to build up enough in numbers to cause the damage this time.
“That was the main problem last year; ravens coming in and hammering the chicks on the floor of the glen.
“I think we would be very surprised, next year, if we did not see high numbers return from the wintering ground, given the sheer amount of chicks we have put away successfully this year.”
While wading bird numbers have plummeted in the UK, ravens have benefitted from full legal protection. Their numbers have doubled since 1994 while Curlew have declined 46 percent in 25 years.
Low breeding success is cited as the principal reason for Curlew population decline.
A recent Scottish Government funded multi-party report, Understanding Predation, concluded that ravens were predators of ground nesting birds and that bold and urgent conservation measures were required to save red-listed waders.
*Roodbergen M, et al. Journal of Ornithology 2012; 153: 53–74.