Wildlife on the Ebb

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W I L D L I F E ON T H E E B B The second Annual Conference of the Suffolk Naturalists' Society was held on Saturday, 26th October, 1991, at the Ipswich School Conference Centre. The event was co-hosted with the National Rivers Authority (NRA) and supported by the Suffolk Wildlife Trust (SWT). Opening the Conference, the Chairman of the morning session, Dr. David King of the NRA, outlined the range of environmental issues effecting the saltwater margins of the East Anglian coast and described the value of the Conference in presenting the activities of the groups involved.

Coastal habitats of East Anglia - Dr. Pat Doody of English Nature Dr. Doody began by describing how the coastal habitats of East Anglia had been influenced by human activities in a number of ways. Fen draining had taken place since Roman times and infilling had squeezed habitats. Some recent developments puzzled him, including the construction of Nuclear Power Stations over some of the 'ephemeral geology of the coast'. Among the many hectares of East Anglian coastal habitats in the care of English Nature it was possible to identify areas that have more in common with some of those along the Mediterranean coasts. Although the flora of our eastfacing cliffs was not subject to salt-spray, the shingle flora of Orford Ness was truly maritime and possibly unique, being a cross between that of both sand and shingle. Although global warming may be taking place and a small increase has been recorded in the sea level, the speaker expressed concern about the amount of unfounded press attention being given to threats from possible sea level rises resulting from climatic change, and the slight, but progressive, sinking of the East Anglian land mass. Erosion of saltings also resulted from the effects of wave action. In conclusion, Dr. Doody stressed the need for site protection, the sustainable use of estuaries, a policy to identify priorities for coastal defences, reclamation of reclaimed saltings, the investigation of the implications of interfering with the natural movement of sand and shingle, and the concentration of minds on the subject of sea level rises.

The health of the North Sea - Dr. Charles Beardall of the Suffolk Wildlife Trust Dr. Beardall delivered a moving and comprehensive talk describing the pollution threat to wildlife around our coast. He stressed the global importance of healthy oceans to the environment. Trans. Suffolk Nat. Soc. 28 (1992)


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Dr. Beardall stated that although large areas of sea are unproductive, the remainder contribute as much as 50% of the oxygen to the atmosphere. The cooler areas of sea water, like that which circulates the British Isles, are among the most productive. Dr. Beardall explained that because sunlight only penetrates the top 25 metres of the North Sea, it is the main breeding ground of a mass of plankton which forms the first element of a food-chain upon which other marine wildlife depends. He also explained how an outbreak of a virus of the Morbillivirus group, which also includes viruses which cause canine distemper and rinderpest, had broken out recently amongst the North Sea seal population, and this had drawn attention to pollution. The increased incidence of anoxia found among fish was giving cause for concern to European fisheries and it was thought to be linked to outbreaks of toxic algae which had been directly linked to high levels of nitrates, two-thirds of which drain into the sea from rivers. Dr. Beardall drew attention to the discrepancy between British and European scientific opinion upon the issue. The disposal of sewage at sea, though only responsible for 1% of nitrate pollution, contributes many toxins of which little is known and of their reactions with the sea or with each other. Heavy metals are being found in the flesh of fish and the occurrence of fish diseases is increasing. Other pressures upon the health of the North Sea described by the speaker included the effects of over-fishing on sea bird populations and the creation of seabed 'deserts' from gravel extraction. Concluding, Dr. Beardall described the present situation as a 'dog's dinner' and stressed the need for Britain to pay more attention to the recommendations and demands of other European countries. The health of the North Sea is declining rapidly and, for its part, Britain must get away from the idea that dilution is the solution to pollution. Seals as marine mammals - Nigel Bonner, Environmental consultant (Former President of the Mammal Society). Nigel Bonner, an internationally-acclaimed authority on seals, gave a most informative and entertaining talk. He began by describing the way seals are divided into three main groups: True, or Earless seals, Walrusses, and Eared Seals, pointed out that seals occupied the nitch between land and sea, and then explained some basic concepts of the biology of seals, illustrated in an informal and entertaining way. The 'design' of seals was very much influenced by the balance of needs struck by individual species which have to exist, to a greater or lesser extent, on both land and sea. They were streamlined for speed in the water and lacked many of the 'bumps' and 'dangly bits' found on the bodies of other mammals. Nor did they have a 'leg' at each 'corner' like most other mammals. The need to be streamlined in the water was offset against the need to be mobile on land. In certain species locomotion on land had been sacrificed to permit greater mobility in water. He also described to an amused audience how some scientists had learned the hard way that other species, like Sea Lions, could in fact move faster than a man on dry land. The 'design' of a seal was also influenced by the cooling effect of water Trans. Suffolk Nat. Soc. 28 (1992)


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which was fifteen times greater than that of air. A factor which was coupled with the relative temperature differences between the air and water in the habitats of individual species. Large Seals had a low surface to volume ratio which reduced heat loss. Additionally, fur-seals could control their rate of cooling by the regulation of the blood supply to their flippers which represented a relatively large extension of their overall body surface area. Seals produce 'clicks', not unlike those produced by Cetaceans, which may be part of an echo-location system, although it has not been proven. However, there are accounts of totally blind but well-nourished seals, which suggest that seals are able to find food in total darkness. Another physiological feature of seals described by the speaker was the relatively large quantity of blood in their bodies, which helps to maintain oxygenation when blood vessels become constricted by water pressure during deep dives. Also, as a protection against high water pressures, blood filled body cavities, like the ears, that were normally empty in other mammals. As the midday break brought to an end Nigel Bonner's fascinating talk, the audience was left wondering what Elephant Seals were doing at depths in excess of 800 metres.

Taking the Chair for the afternoon was Chris Stevens of English Nature, who welcomed the first speaker of the session.

The coastal zone and its protection - Dr. Caroline Heap of the Marine Conservation Society For the wider audience the conference was their first opportunity to meet a group which was more often heard about than seen. Dr. Heap soon demonstrated the organising and crusading role of the Marine Conservation Society and a strategy for action was revealed. She began the talk by applauding the Conference for getting groups together with the common aim of protecting the seas for wildlife and future generations. It is very important, she said, to give people the facts so that they can take effective action. There is a need for coordinated action with an 'Integrated Coastal Zone' and 'Sea Use Management Plan'. The problem of gaining control of the sea is extraordinary because it is seldom owned and lacks frontiers. It is difficult to police. The problems are compounded by the fact that no single Government Department is responsible for marine issues, and condition of the sea is affected not only by its use but also by the influence of shore-based activities. Assessing the value and monitoring the conservation of marine habitats is much more difficult than with terrestrial areas. The speaker described the absence of a background environmental ethic to govern the activities of the ten main sea user groups and prevent damage from diverse piecemeal developments. Users of the sea needed to be environmentally-sensitive and their activities should conform with a concept of a balanced and sustainable use. Coastal Zone Management should


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embrace a number of concepts: a national perspective, a long-term view, an integrated approach, public involvement, a flexible approach and a specific agency. A Regional Coastal Forum should include: statutory bodies, commerce and industry, voluntary bodies, conservation groups and recreational groups. Dr. Heap described the limited success of the two Marine Protected Areas (MPAs) that had been designated around the British Isles. The instrument of their protection lacked 'teeth' and it had not been possible to control their use. In spite of this, there is the need to target additional marine habitats for designation as MP As with larger 'buffer zones' around them. Other areas, identified by the speaker as 'Restoration Areas', were in need of positive conservation. Finally, she described some other aspects of the MCS's activities which included 'Coast Watch UK', a project run jointly with Norwich Union to involve children in marine conservation, and 'Saving Our Seas', an action guide published by the MCS. The final message from the speaker were watchwords: 'Acting On Our Concerns'. Protecting the coastal environment - the role of the NRA - Dr. David King. Dr. King's talk centred round the areas of responsibility incumbent upon the recently-formed National Rivers Authority and a summary of their operations in the spheres of water quality control. He described the vast number of rivers and lakes, and amounts of coastal water subject to the Authority's control. Tasks undertaken by them include the maintenance and monitoring of water quality and the prosecution of polluters. With the prosecution of offenders the NRA's objective is to make sure that the polluter pays. Recourse to a number of pieces of legislation are options open to the NRA. These include: The Water Act 1989, Environment Protection Act and European Commission Directives. He said that he would support the concept of Coastal Zone Management described by the previous speaker and he drew attention to the 16 metre vessel belonging to the Authority which would spend a period of 200 days per year around the coast of Suffolk. Dr. King described the overall quality of water around the coast of East Anglia as good: 68% was Class A , 25% was Class 'B', and 7% was Class ' C . There are not many industrial outfalls in the area. The speaker considered that the Statutory Quality Objective was a better, and more consistent, classification of water quality than previous standards. Dr. King drew attention to the difficulties of providing good, clean water at an economic price, whilst at the same time resolving the needs of recreation and wildlife conservation.

Shorebirds - Tony Prater of the Royal Society for the Protection of Birds. Tony Prater, an internationally-recognised authority on wading birds, was known by the audience as an active ornithologist and a familiar member of most of Suffolk's conservation groups, including the SNS.


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He began his talk by illustrating the role that birds play as 'messengers' for the environment, and pointed out that there are a number of conceptional problems particularly facing the species which inhabit coasts and estuaries. The speaker expressed a preference for the word 'shorebirds', rather than 'waders' because in America, for example, the term 'wader' refers to herons. He believes that the birds are disadvantaged by the poor image that many people have of estuaries as unpleasant places and he stressed the danger of them being 'undersold' to the general public. Doubters, he suggested, should visit estuaries to see the large numbers and variety of birds that assemble on some of the high tide roosts. The study of shorebirds in recent years has seen some significant advances in the development of the counting system, ringing and the research of feeding ecology. The developments had been made possible by the large number of volunteers involved with the programmes. Suffolk had proved to be exemplary with the Birds Of Estuaries Enquiry counting teams. The speaker described the need to identify the importance of feeding sites in an international context. Many shorebirds are itinerant and depend upon food at specific points during their migrations. Patterns of migration vary from species to species and within individual species. Local counts are related to the populations using the Eastern Atlantic Flyway from the counts made in Africa. Europe has 14% of the population in winter and individual sites are recognised as important when they support more than 1%. Ringing has shown that wading birds are remarkably site-faithful and particularly vulnerable if their individual feeding places are denied to them. He described Dunlin as wonderfully dull, grey-brown wading birds and one of his favourites. They doubled their weight over the period from February to April and burned it off during their flight to Iceland. Populations of Dunlin are subject to cyclic patterns influenced by factors like the populations of Lemmings at their breeding grounds. When Lemming numbers are low, predators turn to the next alternative available food source, such as Dunlin and other ground-nesting birds. The speaker referred to the development of Fagbury Point at Felixstowe as a 'classic disaster of our time when political expediency prevailed'. There is evidence that the number of wading birds using the Orwell estuary had been permanently reduced. In conclusion he spoke of the need for the sustainable use of estuaries and for coastal zone planning. He reiterated the value of the ornithological work being done in connection with the birds of estuaries and stressed that scientific knowledge had an indispensable value. Finally, he quoted Voltaire: 'God is not on the side of the heavy battalions - just the best shots.' Whale strandings around the British Isles - Martin Sheldrick of the Natural History Museum. Few of the Cetaceans that end up on the British shoreline escape the attention of Martin Sheldrick and it was about the subject of whale strandings that this speaker addressed the Conference. He began by describing historical evidence that Cetaceans had been

Trans. Suffolk Nat. Soc. 28 (1992)


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stranding around our coasts throughout the ages. Records for such events existed in some detail thanks to the odd classification of them down the centuries as 'Royal Fish\ and by the great public interest aroused by the bizarre events that whale strandings were. By law, whales have been the property of the Crown and have subsequently been reported to the Receiver Of Wrecks. In more recent times the Natural History Museum has been given first refusal of stranded whales. He related some of the more humorous communications that he had received concerning the predicaments of authorities facing the uncertainty of disposing of a large quantity of 'Royal' flesh that was getting progressively more smelly by the hour. He recalled a stranding found with a large 'Police Aware' notice on it. The speaker described in detail some of the species that have occurred on the coast, with some useful guidance about identification of species. His illustrated account of an investigation undertaken on behalf of the Government to explore the health of Cetaceans around Britain, took the audience into a fascinating and gruesome world of animal pathology on a monstrous scale. He interpreted the cause of the many marks that he had photographed on the skins of Cetaceans. A particularly enigmatic mark looked strangely too geometrical to have been the result of a natural cause. It comprised two almost perfectly round scars linked with a broad track. They were, he explained, caused by the circular mouth of a lamprey that had moved its position on the body of the animal without its teeth leaving contact with the flesh. He concluded that excepting young animals, Cetaceans around Britain, especially the Common Porpoise, abound with parasites. Common parasites are Nematode worms. He showed masses of them in the internal organs of his specimens and also in the cavities of skulls where they were often found in great numbers. However, parasitism was not confined to specimens that had become stranded, but was prevalent amongst a representative sample of other Cetaceans. He concluded that there was no connection between parasitism and the stranded animals, and that although Cetaceans around Britain are not healthy, there is no such thing as a healthy wild animal. Drawing the Conference to a close, the Chairman reflected upon what a good day it had been, and that the Conference was a good example of what needs to be done to overcome compartmentalisation. From what he had heard during the day he believed that wildlife was still on the ebb and that, more than conservation, reclamation and creation needed to be the future theme. The day had left him optimistic and, in closing the Conference, he congratulated the organisers for achieving an economical event that was not beyond the reach of us all. E. Parsons (Press Secretary)

Trans. Suffolk Nat. Soc. 28 (1992)


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