Meadow birds - turning the negative trend on the island of Saltholm by restoration of short-grazed meadows by Ole Thorup After five years of supplementary mowing directed at vegetation around wetlands and gullies in former key breeding sites of ruffs, dunlins and natterjack toads, the LIFEBaltCoast project in the spring 2011 achieved its goal: Re-establishment of a meadow management that keeps these meadows with short grass and thereby attractive for the three target species. This made experienced Saltholm ornithologists express: ‘The island is like transformed. It might be 50 years ago the meadows were short-grazed like this. And the transformation benefits the meadow birds’ (BirdLife Denmark (DOF) newsletter: http://www.dof.dk/index.php?id=nyheder&s=nyheder&m=visning&nyhed_id=932). Background Structural changes in animal farming during in recent years, with increasingly more cattle kept in or near their stables and hay becoming of less importance as fodder, are creating difficulties in managing meadows properly for meadow birds and toads. Particular challenges are found at sites where large meadows are situated in places with complicated access for animals and man. Saltholm is a 1600 ha island situated in Öresund between Copenhagen and Malmö. From the 1960es to the 1990es up to 1100 cattle summer-grazed Saltholm and in the ‘golden age’ of meadowbirds in the late 1970es and early 1980es more than 1000 pairs of meadow breeding shorebirds could be found here including 10-20 pairs of dunlin and 3060 females of ruff. During the 2000s it became more and more complicated to achieve summer-grazers and the grazing regime gradually shifted to a lower number of whole-year grazers. At the beginning of the LIFE-BaltCoast project in 2005-06 the number of summer-grazers was down at 150 and in addition 300 adult and 150-250 calves grazed permanently. The average grazing pressure on the island was still quite high, but by inspection it became clear that an unwanted overgrowth had taken place of some of the formerly best areas for the most vulnerable meadow birds dunlin and ruff on the northwest and north-central parts of Saltholm. This unfortunate situation was mirrored in the declining numbers of in particular breeding dunlins. In 1995 there were still 8 pairs, in 2000-2006 the number dropped to 1-2 pairs and at a thorough survey in 2007 no breeding dunlins were found at all for the first time in the hundred years the bird fauna has been regularly monitored. www.life-baltcoast.eu contact: Stiftung Naturschutz Schleswig-Holstein project manager: Hauke Drews email: [email protected] In the same period there were no further records of natterjack toad, a species sharing very much its demands to the breeding habitat with dunlin and ruff, and the species was most likely at the brink of extinction. Project strategy The main aims of the LIFE-BaltCoast project were to • restore the short grassed halophytic meadows with partly overgrown small pools and gullies inside the western shore on the northern part of the island • remove the high and lush vegetation surrounding the central wetlands on the northern half of Saltholm. This strong vegetation prevents the use of the wetlands by meadow birds like ruff, and in addition high vegetation favours an important predator of meadow bird chicks the herring gull, which breeds abundantly and successful in such vegetation • ensure that the present core area for meadow birds like black-tailed godwit, ruff and redshank in a by and large gull free area in central Saltholm keeps its favourable vegetation height and structure Actions There were basically two potential ways to achieve the wanted shift in grazing pattern of the cattle: by force (specific fencing) or by attraction. The LIFE-BaltCoast project tried the second way: to attract the cattle to graze in the targeted areas. A quite simple adjustment was to move the site where winter-feeding of the cattle with local hay took place closer to the areas targeted for more grazing. A more laborious action was to create a cyclic mowing schedule in the targeted areas adjacent to the central wetlands and the slow growing halophytic vegetation to the northwest, areas otherwise unprofitable for achieving good hay and partly also on uneven ground difficult to mow. Immediately after such areas are mown they become very attractive to grazing cattle. In the first place it was considered to add an action with removal of harsh vegetation including litter from some of the depressions in the meadow bird core area However, an evaluation in the summer 2011 showed that during the intensive winter and spring grazing that year, cattle had removed almost all of that type of vegetation. In the first place it was considered to add an action with removal of harsh vegetation including litter from some of the depressions in the meadowbird core area. However, an evaluation in the summer 2011 showed that during the intensive winter and spring grazing that year, cattle had removed almost all of that type of vegetation. An unusually wet autumn, cold and snowy winter and dry spring 2010-2011 with reduced vegetation growth contributed to the efficient removal of the unwanted vegetation. www.life-baltcoast.eu contact: Stiftung Naturschutz Schleswig-Holstein project manager: Hauke Drews email: [email protected] Success In 2010 and 2011 the aim was achieved: The targeted areas have both been restored and are dominated by short grass. In 2010 a large evaluation bird survey was performed and the good state of vegetation management was also reflected in the number of vulnerable meadow birds. One pair of breeding dunlin was found for the first time since 2006, and at a quite brief survey in 2011 two pairs of dunlins were found of which one was seen with chicks. In 2010 also a record high number of breeding black-tailed godwits were seen, 18-26 pairs, and even more promising a minimum of 18 pairs had hatching success that year. Another gratifying result is the fact that ruffs continuously breed on Saltholm. During the last ten years this species has declined dramatically everywhere in Western Europe, and ruffs have disappeared from most of its temperate breeding sites. Apparently targeted management pays for the species, and both in 2010 and 2011 6 breeding females were recorded on Saltholm. This island must now be far the most important coastal site for the species in the Baltic. In Denmark only Tipperne in western Jylland has more breeding ruffs, and this is the only site where management for many years has been specifically directed at suiting the ruff. The Saltholm population constitutes more the 10% of the Danish total, and one third of the ruffs outside the Danish bird reserve Tipperne. Photos 1 to 4 on following page www.life-baltcoast.eu contact: Stiftung Naturschutz Schleswig-Holstein project manager: Hauke Drews email: [email protected] Photo 1: Overgrown central wetlands July 2006. In the past important breeding site for ruff and many other meadowbirds, in 2006 a favourable breeding site for large numbers of herring gull – an important predator on meadowbird chicks (photo by Hauke Drews) Photo 2: The central wetlands in June 2011. Mowing specifically directed at removing the lush vegetation here and grazing have created an open meadow, not very attractive to herring gulls as chicks can no more hide, and now suitable for meadowbirds (photo by Martin Altemüller) Photo 3: From 2006 to 2009 the halophytic vegetation Photo 4: In June 2011 the aim has been achieved. All over between the central wetlands and the west coast tthe halophytic vegetation has become short, and the dunlin gradually became more open due to grazing and mowing. iback as a breeding bird. Two pairs were found in 2011. But in June 2009 several pools and gullies were still (photo by Martin Altemüller) surrounded by vegetation 10-20 cm high. Not a perfect vegetation structure for e.g. dunlins. (photo by Martin Altemüller) www.life-baltcoast.eu contact: Stiftung Naturschutz Schleswig-Holstein project manager: Hauke Drews email: [email protected]
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