Norfolk’s Notable Ninety

Norfolk Wildlife Trust looks after habitats; and does it well. We often assume that the heaths, dunes woods and marshes are being managed for our benefit but in reality they are managed for the species that created them and make them work. Collectively these species are known as the biodiversity of the habitat, and there are a very large number of them. How many? In Norfolk, more than 2,500 beetles, 1,600 flowering plants, and 3,000 fungi just for starters. Recent studies by ecologists at the University of East Anglia found records for 12,500 species in the thousand square kilometres of Breckland, and 11,000 species in just over 800 km2 of the Norfolk and Suffolk Broads. Because it has such a wide variety of natural habitats, coastal and inland, Norfolk is one of the most biodiverse counties in Britain.
 
The casual wanderer will notice very few of these species, however, just the larger plants, birds, butterflies and a few mammals. To find the rest you might need to turn over a log, dip a net into a pond or set a trap, and for many the search is even harder. And this is just on land and freshwater: look at the sea and it appears lifeless, something it is most certainly not.

Norfolk holds great attraction for naturalists who come to see iconic species such as stone curlews, otters, swallowtails and its rich coastal and wetland floras but the Norfolk Wildlife Trust’s 90th anniversary provides an opportunity to widen the scope and celebrate a few more species which are special to Norfolk. Some will be relatively well-known and loved; many more will come from the hidden masses, often rare but for which Norfolk may well be the best place in Britain to find them. During the anniversary year, the profiles of ninety such species, Norfolk’s Notable Ninety, will be added to the new anniversary website a few at a time.

Sandy Stiltball, credit Tony Leech

The term ‘notable’ has had a special meaning in conservation as it was once used to describe species known to occur in between 16 and 100 10 x 10 km squares in Britain. Some of our ninety are indeed notable in this restricted sense but some are commoner and a good number even rarer and designated Nationally Rare. To select our Notable Ninety, County Recorders and other naturalists were invited to propose species from which list a small panel from the Norfolk Wildlife Trust and the Norfolk & Norwich Naturalists’ Society made a final (and inevitably subjective) selection.

County Recorders are mostly amateur naturalists (although some are professional biologists) who bring together records of where and when species in their specialist group occur within the county. Around thirty-five men and women record species, from whales to aphids and from bats to mosses. In fact there are virtually no organisms with more than one cell which do not capture the interest of a County Recorder. Their task involves checking the validity of records they receive and then passing them on to Norfolk’s Biological Record Centre, managed by the Norfolk Biodiversity Information Service at County Hall. In time these are uploaded to a national database, the National Biodiversity Network Gateway (https://data.nbn.org.uk/) and to various national recording schemes. Many of the County Recorders also promote public interest in their chosen group; to find who they are visit the Norfolk & Norwich Naturalists’ Society’s website.

Naturalists have a reputation for seeking out the rare - some birdwatchers will only stir with the prospect of a new ‘tick’ – but however dismissive some are of rarity-hunting, for most of us the possibility of seeing something less usual adds another layer to our appreciation of the natural word. I suspect that our fascination with the rare arises from a fundamental human trait that has aided survival; the ability to recognise the unusual and then to work out whether it offers an opportunity or a threat.

But are rare species important in the wider scheme of things? They certainly can be. For example, populations of top predators cannot be stable unless their biomass (the weight of all of them together) is at least twenty times less than that of their prey, and so on down the food chain. Since top predators, for example barn owls and otters, must be large to catch animal prey, their numbers have to be very low. Most parasites sit at the opposite end of the size-scale. The ichneumon wasp Trogus lapidator has been found in just two 10 x 10 km squares in Britain, both in East Anglia, but as a parasite of the swallowtail butterfly it could in principle determine the abundance of its host.

Starlet Sea Anemone, photo by Rob Spray

Behind almost all of our chosen ninety is a story, rarely adequately told in a 100-word profile but hopefully sufficiently well to engage the curious. The story might feature a bizarre lifestyle or a chance discovery; it might be a story of gain or loss. As alluded to above, marine species rarely get attention unless they can be seen from the shore. One that could be, but hardly ever is, is the starlet sea anemone. Most sea anemones live on hard surfaces in the sea but this one occurs in mud at the bottom of brackish pools where salinity is often much lower than in the sea. In Britain, the starlet sea anemone is found only in Hampshire, Suffolk, Essex and on the north Norfolk coast. In the 1960s it occurred in Abraham’s Bosom Lake at Wells and in Half Moon Pond at Cley but water quality deteriorated in the former and coastal erosion has destroyed the latter. Fortunately a translocation programme, probably aided by natural dispersal, has resulted in the anemone colonising brackish lagoons and ditches on land newly-acquired by Norfolk Wildlife Trust at Cley.

To become a dot on a distribution map a species has to be correctly identified, something which all too often requires specialist knowledge gained over many years. Maps can so easily depict recorder effort rather than biological distribution. However, some species are so unambiguously identifiable by anyone that, for example, the scarcity of the sandy stiltball, a fungus which looks like a furry orange lollipop, is probably genuine. But it seems to be getting commoner! This distinctive species was discovered, new to science, on the Norfolk-Suffolk border in 1782. For over two centuries it remained very rare in Britain but in the late 1990s several new sites were found in Norfolk. Then, between 1995 and 2001 it was recorded in five more places and, since 2011, at a further six. All of these recent records have been from roadside banks and verges.

A species does not have to be rare, or even resident here, to be special for Norfolk. As many as 60,000 knot, a small wading bird, have been counted at one time at Snettisham. These are mostly the islandica form, or Greenland knot, passing south. It has been estimated that almost half of the world’s population of the pink-footed goose spend their winter in Norfolk gorging on sugar beet tops, and wintering shorelarks can be seen here more reliably than anywhere else in Britain. Flocks of migratory birds attract flocks of migratory birdwatchers but if you are fortunate enough to live in the county just revel in its biodiversity. Hopefully our notable 90 will whet your appetite and help you on your way.