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Nature reserve design Peter Shaw USR Introduction My qualifications for giving this lecture? 6 months as warden of Rostherne mere NNR, Cheshire 3 years organising a conservation group at CERL, Leatherhead. Aims for today: to introduce the basic ideas and themes of reserve design and management to identify some of the practicalities to be faced. Step 1: WHY? The first stage in planning a nature reserve is to identify its purpose. This is not as trivial as it may seem: Protect unknown species (rainforest biosphere reserves) Protect a nationally scarce species (bitterns, avocets at Minsmere). Protect a habitat (lowland heath at Headley heath) Protect a local population (Globe flower wood in Yorkshire) Educate kids (Tilbury power station nature trail) Stage 2: Find your warden! A reserve needs a warden. His/her job is to know the site intimately, to guard records of site history and gather new data. It also involves means planning and running the site management There is a great deal of people management - from shooing off trespassers to showing visitors around and giving talks in the evenings. Keep out the vandals without annoying the locals! Involve the locals! This is a potential issue in the UK, but has been a serious problem in many tropical ex-colonial countries. The issue is epitomised in Africa, where parks/reserves meant areas in which white people told the real locals how they could/could not use their land. Without goodwill, conservation will not work. In Costa Rica the policy is that park wardens must be locals this involves locals in park policy. (It probably helps that Costa Rica has no large valuable game animals). At a lower level, it is always worth taking the time to keep local people informed of developments or plans. Dilemma: In 1997 a yew plantation was cut down on Box hill for timber. In its place a new yew plantation was created – baby yews + many species of chalk downland plants. The locals knew nothing about this until felling started – and would certainly have stopped the work had they known in advance. Was the council correct? Pere David’s deer This odd animal is close to the common ancestor of deer and goats. It only survived in the deer park of the Chinese emperor. Peasants who trespassed in the park were liable to execution - good protection you may think. No! In the Boxer rebellion (1919) the emperor was overthrown, and all deer in the park eaten. The species is only alive thanks to pere David Armand, who previously took a few animals back to Europe. Management plans The definitive document concerning the management of any nature reserve is known as the Management Plan. This is usually a fat document, always the bane of a warden’s life! There are a variety of different, tightly-prescribed formats, but all have certain common features: site information: geology, habitat composition, management history, soil profile, hydrology etc. Biological records: bird populations, plant surveys, fungal forays etc. Legal constraints: footpaths cannot be blocked, common land may not be fenced off, shooting rights be be separate from land ownership. And future plans.. The management plan also needs – oddly enough – plans for the management of the site. These plans will extend well into the future, typically 5-20 years. I want to spend a while exploring the types of management that might be considered, and some of the theory behind it. Three sections: People management Habitat Management Underlying ecological theory. People management: People are a nuisance! At the same time they are the raison d’être of a reserve (supplying the money to maintain it, directly or indirectly), and they are the most dangerous and damaging creatures on the site! The site needs secure boundaries, and the entrance needs some sort of introduction: Laminated signs for un-staffed sites, grading up to palatial visitor centres such as the WWT centres. The visitor centre at WWT Slimbridge Paths You need to control people – keep them to designated paths if at all possible. (Even in huge areas of wilderness like the high Pennines, visitor pressure is a nuisance). Keep a good surface on paths – boggy bits expand sideways! Have at least some paths accessible for wheel-chairs. Maybe have a nature trail, with numbered posts and a guide pamphlet. Do they need to get close? At Rostherne mere the closest access was 400m away, but the hide commanded such a good view of the lake and had such a powerful telescope that this was fine. (We had the woods to ourselves). Protect the habitat from the people! Willow logs can surface wet paths. Paths lead to hides – anything from a garden shed upwards. These effectively isolate humans from the birds/animals they are watching. Screens can prevent shy birds from seeing people on exposed sections of paths – especially useful close to hides. A hide for all ages Dogs are a nuisance! Sorry dog lovers all.. On a nature reserve, virtually everything that dogs do is undesirable – notably chasing animals (from deer to lizards), disturbing ground-nesting birds, and fouling the soil. Where possible it’s guide-dogs only, but on common land this cannot be enforced. Headley heath has 600 dogs per day, most leaving from one car park. Wimbledon Common has packs of 40 dogs, brought taken from all over London by professional dog walkers. (Is now 6 dogs:1 handler) Protect people from the habitat! The prospect of litigation drives many site managers to play safe in all safetyrelated matters. Keep paths clear. Fence off any potentially dangerous cliffs or water bodies. Assume crass stupidity to be a characteristic of all visitors! (And remember that kids drown quietly). Bempton cliffs had to fence off one of their better puffin-viewing platforms,as there were suspicions about the cliff’s safety. Features to add in: Depends greatly on the site. For pristine sites, biosphere reserves etc the best thing to do is probably nothing at all. Most UK reserves include newly-created or modified habitats, which can act as visitor foci as well as adding to biodiversity. Ponds – with a dipping platform? Scrapes – for waders, overlooked by hides. Nestboxes – benefit mammals too Wildflower meadows – check your notes! More violent management: Reserves often need to control animals. This is a euphemism for killing them. In 1979 Rostherne had a team who spent the summer putting cymag down rabbit holes, gassing them. (Now banned I believe). We also had long-netting sessions at night. Foxes can be pests. Passions run deep about killing birds: Gulls can be serious egg predators. Canada geese ruin vegetation on lakes in summer. Egg pricking may be preferred to shooting. Kestrels at Minsmere took to feeding on chicks of little tern Sterna albifrons (world population <3000). Plans to shoot the kestrels led to mass resignations from the RSPB – compromise was to put out trays of dead mice for the kestrels. More on killing animals The extreme case concerns a reserve for native Astralian animals, run by John Walmsey (“The only good cat is a flat one”). He excludes european fauna to conserve Bettongias, wallabies, platypus. Local eco-vandals took to throwing live cats over his fence, so he now has a double fence around the reserve, with spacing between the two fences greater than an Aussie can wang a cat! When we consider remote islands, I’ll have more to say on killing animals. Underlying ecological theory: It is possible to invoke standard ecological theories to predict how best to design nature reserves. The extent to which these theories work is still being assessed.. Features we can consider: reserve geometry successional management Geometry S A Bigger sites have more species, by a wellknown relationship describing how species richness on islands scales with island size: S = C Az S = Species richness C = a constant for a given system A = area z = a scaling constant, typically 0.1-0.35 This means 10* area = 2* species (roughly). But what if you have the choice of one large or several smaller reserves? This is known as the SLOSS debate (Single Large Or Several Small), and is usually won by one large site – especially for conserving large predators. Shape? Connectedness? Often you simply buy what you can, but if there is a choice you should aim to optomise the site geometry. Consider edge effects – good or bad? (Good for UK insects, bad for deep rainforest species). Connectedness is always good Better Worse Successional management This has been mentioned before, but we can now generalise it. It is often essential to manage a succession to preserve a species or habitat. Managing for latesuccessionals is easy – wait! The problem comes with early-mid successional species. Here you have to re-set the succession, usually by heavy machinery. Examples of seral stages: Heather on heaths – needs regular mowing/ disturbance. Coppicing in woodlands to maintain a habitat mosaic. Natterjack toads are replaced by common toads. The hydrosere: Open water Reed bed Carr woodland Willow scrub Reedbeds matter – far more than lakes! Reed beds are nesting habitats for some of our rarest birds: bitterns and bearded tits. (Also rails, crakes, harriers..). To maintain them involves controlling the water table and the succession – particularly willow scrub. Summary – golden rules for reserve management Know your site (in time as well as space) Aim for diversity of habitats If there has been a constant management regime for many years – keep it up! Don’t be afraid to reset a succession. Always worry about people!