RSPB LAND RESTORATION IN EAST ANGLIA

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RSPB LAND RESTORATION IN EAST ANGLIA ROB MACKLIN I heard on the news recently that eight billion pounds is required to make the railways run on time. Then I heard that the Water Utilities also need several billion. –I think that we will have probably cracked habitat restoration when it’s on the news that eight billion is going to be spent by government to rehabilitate all our wonderful wild areas. It’s not happening quite yet unfortunately, but hopefully it will in the future. Until that time it is up to all of us to try and sort things out.

I’ll begin by discussing one of our sites at North Warren, north of Aldeburgh, which we bought in 1939. It was originally managed as an adjunct to Minsmere and suffered from benign neglect. Although a lot of work was done over the years on straightening the river, the reedbed was not managed and scrubbed over. In 1990 we bought the local grazing marshes from a farmer who was going out of business. We got English Nature involved in the decision on what was to be done about the reedbed and in the end we decided to do something quite radical. We decided to dig it up. Habitat management on this sort of scale hadn’t been attempted before in the UK. The whole idea behind digging it up was to try and lower it by about 30 cm, principally because we needed to get water onto the site without flooding the surrounding areas. The reedbed was full of willow and alder scrub so one morning a digger was brought in and in one day the whole lot was removed and burned.

To begin with we were worried that there wouldn’t be enough water coming onto the site, but these worries proved unnecessary as the area was fed by numerous small springs and things began to change rapidly. We bunded off the river because we would rather the reedbed was fed from spring water. We also bunded off the sewage ditch which was very high in nitrates and phosphates. It was a huge task and the amount of peat spoil we generated as a result was enormous. Unfortunately it wasn’t ethical to sell this off to gardeners but luckily peat oxidises quite well. We only took the reedbed down 30 cm because we didn’t want to remove the rhizomes. We had to use 20 tonne, wide-wheeled dumpers so that they didn’t sink into the reedbed. The reedbed re-colonised extremely quickly, especially considering that just a year before it was so dry you could have walked through it in your slippers. It has cost in the region of £5,000 per hectare which English Nature and the Countryside Agency have been helpful in funding. Although it has taken a lot of money and work this has produced a pristine habitat. We also dug in two miles of new dykes which we angled so that they were perfect for feeding birds such as Bitterns and Herons etc. Where deep-rooted 40 or 50 year old willows were ripped out they left big holes which became excellent habitats for fish. People assume that the RSPB is just concerned with creating habitats for birds. This is no longer true; the RSPB now looks at the wider environment and many of its wardens are Suffolk Naturalists.

Otters have re-colonised this area, we don’t know if present populations are part of the original population that was around the Thorpeness area until the early 1970s or if they are a product of releases that went on in the 1980s and 1990s. Water voles are also very common here, we trapped over 20 males as part of a London University research project – 17 of those were killed Trans. Suffolk Nat. Soc. 40 (2004)

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almost immediately by stoats. An amazing amount of dragonflies have colonised the site. The site now holds 20 to 21 different species, this year Redveined Darter appeared to be colonising, Small Red-eyed Damselfly is now one of the commonest damselflies on the site whereas three years ago it was totally unknown (possibly as a result of global warming).

The whole management of this site was originally driven by bittern. The project cost about £100,000 for the 22 hectares and I am happy to report we have now got two booming males. We have two nests this year and we had two nests last year as well. At our first ever nest in the reedbeds we tagged one of the birds which then nested at Minsmere the following year, so its good to see them moving around. We know one of the chicks died but we don’t know about the other – it’s hard to keep track of them, but it is very encouraging that two nests have established in such a short time.

Other things that have happened on the site are that birds like Osprey are quite regular on passage feeding in the open water areas of the reedbed, and on Thorpeness Mere – it’s great to see them. Lots of fish are in the reedbed e.g. roach and rudd and this year also lots of pike, (how they got there I don’t know) – hopefully the otters will eat most of them because there were few wild fowl broods this year. It seems likely that it won’t be long before Osprey breed in Norfolk and Suffolk as they are a species which could easily colonise.

Further north at our famous reserve at Minsmere – the reedbed here is about 180 hectares. There is not much open water in this area of reedbed. The reedbed was fantastic for Bittern 30 years ago. As reedbeds tend to dry up we have introduced a hand reed cutting programme covering about five to six hectares per year on a seven year rotation and this does provide some feeding area for Bittern. However, a lot of the reedbed had gone beyond this stage so we brought a digger in to the eastern end of the reedbed which over four years lowered 40 hectares. We were able to use the spoil on this site locally which saved a considerable amount of money as moving spoil is very costly. As well as scraping off the litter, we put in lots of new ditches, banks and pools and the existing dykes were also cleaned out. What we are trying to do is to get a high proportion of open water and reed edge which seems to work well. It has been quite successful, particularly in the area behind South Hide which was recolonised remarkably quickly, Bittern were nesting here within 2 or 3 years.

The pool behind West Hide was covered in sycamore. This was lowered in February 1997 and literally 3 years later it has evolved into a fantastic habitat with lots of open water and reed fringe. Open water is extremely important for the Bittern as pure reedbed is incredibly difficult to move through.

The North Levels Project project at Minsmere started in 1999. It involved about 29 hectares of very dry land which was completely choked by scrub with no open water and had very minimal conservation value. Again this was lowered, the dykes cleared and the ditches widened to provide lots of open water and reedbed interface. Now it is a fantastic Bittern feeding area with lots of wildfowl, fish and dragonflies. Norfolk Hawker dragonfly now seems to have colonised Minsmere, I don’t know how, as there is no Water Soldier there, but there is Frogbit which may be one of the foodplants. Some of the pools created in this area are up to three metres deep so provide refuge in hot

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and cold weather for fish. Once we have gone to all this time and expense to restore a habitat we don’t want to spend a lot of time on intensive maintenance so the solution to this problem has been to bring in the Konik Horses, or Tarpans as they are often known. These animals come from Poland, they love to wallow in these wet conditions and they graze the area trampling up the rhizomes. They require some wood in their diet so they also take out a lot of willow scrub. We have a stockman who regularly checks on them, but they don’t need a lot of looking after. We originally rented five Koniks from the Suffolk Wildlife Trust but now we have bought another eight and we intend to get the numbers up to 20 plus, by breeding. We are also going to excavate some areas on meadow marsh but the horses are key to the management of this area. Although this has been a costly project it has been well it worth it in terms of the species which have recolonised. In the case of Bitterns there are now eight booming males, ten nests and lots of young which are colonising other reedbeds in East Anglia. In 1971 there was only one pair of Marsh Harrier in Britain, at Minsmere. There are now approximately 160 pairs in the UK and 28 young were fledged at Minsmere this year. Occasionally Bittern and Marsh Harrier will take each other chicks but the majority get on and survive. Bearded Tit have also responded exceptionally well to management of this area with over 50 pairs at Minsmere and 15 pairs down the road at North Warren. Reed Warbler are doing even better with approximately 300+ at Minsmere and 70+ at North Warren. Water Rail – (a species which tends to get overlooked) makes a distinctive squealing call and numbers have been counted using tape lures. There are about 60+ pairs at Minsmere and 50+ at North Warren.

Another site I want to tell you about is at Lakenheath in West Suffolk.

Here the RSPB bought 300 hectares of land that was previously a carrot field with the intention of turning it into a reedbed. We appointed one of our best reedbed experts – Norman Sills to sort this place out. The hope was that by 2010 we would get reedbed and grazing marsh in here with poplars at each end to provide habitat for about five to eight pairs of Golden Oriole. The project was by no means easy. We had to build a 4 km long safety bank to stop water seeping out and flooding surrounding areas, a 4 km long channel to intercept seepage water trying to get out and we also had to divert 1 km of IDB main drain. We tend to use the contractors PRF – they are very reliable and have worked with us on other projects for many years. They have dug 20 km of channels, 10 hectares of meres, 12 km of banks and 20 sluices have been installed to control water. With the help of many fantastic volunteers from all over the county, we have developed considerable expertise in successfully planting reed. Every year 30,000 stems are reared in polytunnels and now a third of a million reeds have actually been planted here. Just two years after planting the first Reed Warbler nested and now a number of species have responded astounding well to the new conditions. This old carrot field now has 406 pairs of Reed Warbler (the highest concentration in Suffolk), 141 pairs of Sedge Warbler and 163 pairs of Reed Bunting (this species is on the Red List for birds of conservation concern). This represents a phenomenal success and we are able to pass on the expertise we have gained during this

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project to partners and other stakeholders. One of the problems of planting reed is that coot like to feed on them, so it is essential to net vulnerable areas off. This year there were 136 pairs of coot on the site so there is a lot of grazing pressure – luckily no Greylag so far as they would also cause a lot of damage. It is hoped that Bittern will move over to Lakenheath in the next few years as we lose suitable habitat on the Suffolk Coast over the next 20–30 years. Benacre and Easton Broads are already saline, Walberswick is under immense threat from sea level rise and Minsmere may well go too. North Warren is more protected but it is only 22 hectares. So this massive 300 hectare site at Lakenheath is going to be vitally important if we are to retain our bird species. Work here has cost at the most £2,000 per hectare so has not been as expensive as our North Warren experience. The first Bittern was seen in the winter of 2003, the first summering one on the 31 August 2003. The aim here is for five pairs of Bittern and 40 hectares of poplar with five pairs of Golden Oriole. Twenty five Hobby were seen over the site in June 2003; presumably they were after St Marks flies or dragonflies. Marsh Harrier now nest and Bearded Tits have wintered. We have a good water supply for the soils. There is a pipe through the river bed and we have a licence to extract a million cubic litres from November to March. Water is re-circulated using two automatic pumps. Wind power would have been preferable but it would have proved to be completely inadequate on this site.

Another significant project we are undertaking is an area of 700 hectares of land near a village called Needingworth in Cambridgeshire. The aim is to create a wetland site; the reserve will be called Ouse Fen. It is a Hanson Aggregate and RSPB Wetlands Project, 28 million tonnes of aggregate is being removed from the site, this represents one of the biggest projects in Europe. We have had tremendous support from Cambridgeshire County Council and there will be a phased acquisition programme over the next 30 years until the whole project is completed and extraction is finished. In addition to creating reedbeds and grazing marsh there will be 30+ km of new rights of way for walkers. At the moment there are four diggers working on the first 20 hectares which as recently been purchased. Local people have also been consulted about this project and they have been favourable and supportive. In a few years it will be a fantastic habitat and we are looking forward to breeding Little Egret and perhaps breeding Great White Egret species which seems to be moving west and north. Dragonfly numbers should also go through the roof. When doing this sort of restoration we want to make sure that the whole gamut of species survives. We were concerned how this sort of work would effect our rarer moths. Suffolk Moth Group have been brilliant at monitoring this by doing trapping up at North Warren and at Minsmere. Last year they had their biggest ever catch at North Warren and they caught White Mantled Wainscot which needs older relict reedbeds, this is very encouraging.

RSPB are also creating new habitats from arable land (planted with winter wheat) near the Suffolk coast at Minsmere. The area we bought was about 160 hectares of arable which we thought had been heath about 50 years ago (actually it was 200 years ago!- so the amount of lime that had gone on to this

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in the meantime had been quite extensive). What we were aiming for originally was planting with Heather (Calluna), both Western and European Gorse, and acid grassland. This proved a lot more difficult than we thought. In Dorset we have managed this on land that had been planted with conifers.

Once the pine trees are removed the seed source is still there and it is possible to restore heathland. However, the seed source at Minsmere had long gone leaving a lot of rank grass. We therefore engaged a Phd student Kathy Owen to do a three year project under the auspices of Professor Rob Miles at Liverpool University who has a lot of experience in soil restoration. We needed to get the soil back to a higher level of acidity. So Kathy looked at soil acidification and vegetation establishment techniques. We needed to get nutrients out the of the soil, although initially we did have to put some fertiliser on the soil to grow a crop that could take more nutrients out of the soil. The whole crop was then combined off, stubble removed and gradually nutrient levels declined. However, this was an extremely slow process. So we tried something else, we decided to put sulphur on to the ground - something which was done by farmers as much as 200 years ago to make their land more acidic. This was partly funded through the Tomorrow’s Heathland Heritage HLF Programme. Initially we found that the powdered sulphur blew away too easily so we tried it in a pelleted form and now we are experimenting with ferric sulphate. The sulphur helps bacteria in the soil to lock up phospate; it neutralizes the lime and increases pH. Now that we have acidified the soil, we are putting on heather seed from our neighbouring site and from Dunwich Heath and we have also put on acid grassland seed. This seems to have worked quite well. It has taken ten years to get to the stage where the heathers are beginning to take hold. This year hasn’t been brilliant, we have had a lot of die-back because of drought conditions (as have most of the heaths across the county) but it has taken off on the open areas of soil. The grassland areas need to be managed and the only way to do this is by sheep grazing. The grass is not good enough yet for Suffolks so we tend to use Beulahs which are hill sheep that survive well in these conditions. Until now we have been using the Suffolk Wildlife Trust sheep for many years, but now the Trust is concentrating more on Hebredians which are not suitable for this environment so we have engaged a local grazier who has Beulah Sheep. We have also got 32 Manx Loghtan Sheep, they are very good browsers but not particularly good grazers. They look very fierce but of course they are not (if you're at least 100 yards away!). We will probably use this breed on some of the other heaths around Aldringham and North Warren. We are also hoping to increase rabbit numbers. Everybody thinks that rabbits are everywhere but they are not where you want them, and this autumn has been very bad for myxamatosis.

Stone Curlew is the main species driving this project; they are doing very well in the Brecks and Wessex but we want to get them back on to the Suffolk Coast. This year on the Suffolk coast we had five breeding pairs and at least seven other birds visiting. It probably won’t be long until these visiting birds are breeding. If they do, we will try to set up a visitor and viewing angle so as long as it doesn’t disturb them. Stone Curlew need large areas and things are looking good this year. Woodlarks which are in steep decline on the Suffolk

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Coast will also use these areas. Pre-1987 they were exceptionally rare but the numbers shot up when parts of Rendlesham, Tunstall and Dunwich Forests blew down in the 1987 hurricane. We are still managing to hold on to some of these as they move onto surrounding heaths and there are over 100 pairs at the moment.

Can we attract some of the things we have lost? For example Wheatear (quite common on passage), but does it still breed in Suffolk? – Well, it breeds on Orfordness and last year there were three pairs at Woodbridge Airbase. It bred in an area where there were thousands of rabbits so it’s this sort of area we are trying to get back if we can. Green Hairstreak had an appalling year on the Suffolk Coast this year in spite of what looked like reasonable conditions, but their populations do seem to fluctuate, five years ago they had a fantastic season. This species needs the European Gorse, so if we make mosaics of Gorse and heathers species like this should do well. Grayling is another notable species which is nationally in decline, on the Suffolk Coast it seems to be holding its own, but more of these acid grasslands and open sandy areas can only assist its fortunes.

There are two more big projects like these I have discussed that are in our heads at the moment and they will come through when, and if, we get somewhere with them. The future in some ways is looking quite optimistic.

Rob Macklin Suffolk Area Manager River Hundred Aldeburgh Road Aldringham Suffolk IP16 4QP Rob’s responsibilities include overview of all RSPB offsite activities in Suffolk including all agricultural work, liaison with Forestry authorities. He is a member of the Suffolk Sandlings Group and Suffolk Coast & Heaths Partnership. Responsible for the RSPB acquisition strategy in Suffolk and site manager of the North Warren & Aldringham Walks Reserve. Member of Council of SNS and SOG also committee member of SORC and Alde & Ore Association.

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