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Caring for the environment
Many seabirds are unique to the Seychelles. According to Lord Richard Percy of the department of zoology, University of Newcastle upon Tyne, of the large populations of tern species breeding and feeding on and around the islands, the fairy or white tern (Anous alba monte) and lesser noddy tern (Anoust.tenuirostris) are particularly rare. Further diminuition of numbers of these species, for example, by oil would be disastrous.
Caring for the Environment Three recent moves in the United States should go a considerable way towards helping preserve the natural environment. During the first half of J u n e President Nixon urged Congress to give early approval to legislation cancelling twenty federal oil leases in the Santa Barbara Channel area, California, where the disastrous blowout occurred in January, 1969, and to create instead a federal marine sanctuary. The area which would be closed off to future drilling is about 82,000 ha, extending from 32 km off the Santa Barbara coast to Santa Cruz, and about 28 km long. Firms that leased the sites some 10 years ago will be compensated b y revenue from oil production at the Alk Hills naval petroleum reserve, also in California. How much compensation the firms should receive will be decided by a federal court, b u t it is likely to be more than the $178 million which they originally paid as they have invested money in drilling wells. None of the firms has announced whether oil or natural gas have been found. The population of Santa Barbara would no doubt be happier to see all offshore drilling in the area forbidden, b u t as fifty federal leases have already been sold nearby, this is obviously not on the cards. Besides, as reported in the 'International Herald Tribune' for 12 June, pumping in the area will have to continue for at least 5 years and perhaps for as long as 20 in order to reduce the pressure to a point where capping is possible. The second move is the virtual ban, imposed by Secretary of the Interior Walter J. Hickel, on the use of DDT, aldrin, dieldrin, endrin, mercury compounds and nine other lesser known agents on vast areas of federal land. Thirty-two other chemicals and classes of chemicals will be placed on a restricted list allowing them to be used under limited circumstances, b u t only with the approval of the cabinet subcommittee on pesticides. The ban follows closely on the heels of an a n n o u n c e m e n t on 8 J u n e by the Olin Corporation, Alabama, that as from 30 J u n e it will halt production of DDT ('International Herald Tribune', 10 June). Three days earlier a suit had been filed in the Federal District Court in Washington by three conservation organizations asking that Olin, which produces 20 per cent of DDT manufactured in the US, be prohibited from discharging wastes containing DDT into water leading into the Wheeler Natural Wildlife Refuge in Alabama. Last, b u t b y no means least, as reported in 'Nature' (226 : 999; 1970)~ the signs are that the US Administration has accepted the recommendations of the commission under Mr Roy Ash on government organization that there should be set up an agency specifically concerned with the environment. Under the commission's proposals the agency would take over responsibility for water pollution from the Department of the Interior, for oil pollution and solid waste from the Department of Health, Education and Welfare, and for the regulation of pesticides from the Department of Agriculture. Programmes for the regulation of sewer systems could also be transferred to the new agency as could the work of the Food and Drug Administration. Apparently included in the commission's proposals is
one urging the setting up of an agency to be largely concerned with research and development in the environmental field.
Sewage Pollution affects Fish Increased discharge of chlorinated sewage effluent into the Little Patuxent River, Maryland, USA, between 1958 and 1967 caused changes in fish migration, abundance of resident species and the composition of the river's fish community. Changes in the n u m b e r of species and abundance of fish were most evident immediately below a sewage outfall. These findings, based on thrice yearly sampling at three stations along the coastal plain sector of the river, are described by Chu-Fa Tsai in a recent issue of 'Chesapeake Science' (11 (1) : 34 ; 1970). Two new sewage plants were constructed between 1958 and 1967 along the.sector of river examined, their discharges increasing substantially each year. During the same period the flow of the river was reduced by approximately 22 per cent. Tsai's analysis in 1967 was a repeat of that performed by Sanderson in 1958. Fish trapped at the three stations were removed, sorted and counted for three 10 day periods during April, June and September. According to Tsai the three stations represented areas with water of different quality. Thus station 1 upstream of the point of confluence of the Patuxent and Little Patuxent rivers was an area of little organic enrichment, without a decline in dissolved oxygen (DO) in the summer as compared with 1958 but with increased pH. Station 2, 13 km downstream of station 1 and only 270 m below a sewage outfall represented an area reflecting the direct effect of chlorinated sewage effluents, there being a decrease in June 1967 of DO and a general increase in the biological oxygen demand, and dissolved solids compared with 1958. Like station 3, 4.3 km downstream which also had a reduced DO content in June, 1967, station 2 was an area oF organic enrichment. Changes in water quality were reflected in the migration patterns and distribution of several migratory fish species. Thus the total catch of white catfish in 1967 was 257 compared with 312 in 1958. Together with white perch, white catfish was the dominant species at stations 3 and 2 during the spring spawning migration in both 1958 and 1967, b u t the abundance of the species was drastically reduced at station 2 in J u n e 1967. During the same period the number of white catfish increased downstream at station 3, which suggests to Tsai that upstream migration of the species was prevented b y the chlorinated sewage effluents concentrated at station 2 immediately below the sewage outfall. Similarly, the upstream migratory range of the potandromous white sucker and northern redhorse decreased between 1958 and 1967. The effects of sewage pollution on resident species were much greater. At station 2 there were fewer of each resident species in 1967 than in 1958, while at stations 1 and 3 the patterns of change varied according to the degree of tolerance to pollution, the habitat preference of each species and the amount of pollution. As regards the structure of the commtinity, at station 2 there were in total 82.7 per cent fewer individuals and 26.4 per cent fewer species in 1967 than in 1958. At stations 1 and 3 the number of species was fairly constant from 1958 to 1967, but the species composition changed significantly, probably due to increased organic enrichment and thus decline in DO content. These changes were greater during April and J u n e than during September, chiefly as a result of the changes in population of the dominant migratory species.
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Caring for the Environment Three recent moves in the United States should go a considerable way towards helping preserve the natural environment. During the first half of J u n e President Nixon urged Congress to give early approval to legislation cancelling twenty federal oil leases in the Santa Barbara Channel area, California, where the disastrous blowout occurred in January, 1969, and to create instead a federal marine sanctuary. The area which would be closed off to future drilling is about 82,000 ha, extending from 32 km off the Santa Barbara coast to Santa Cruz, and about 28 km long. Firms that leased the sites some 10 years ago will be compensated b y revenue from oil production at the Alk Hills naval petroleum reserve, also in California. How much compensation the firms should receive will be decided by a federal court, b u t it is likely to be more than the $178 million which they originally paid as they have invested money in drilling wells. None of the firms has announced whether oil or natural gas have been found. The population of Santa Barbara would no doubt be happier to see all offshore drilling in the area forbidden, b u t as fifty federal leases have already been sold nearby, this is obviously not on the cards. Besides, as reported in the 'International Herald Tribune' for 12 June, pumping in the area will have to continue for at least 5 years and perhaps for as long as 20 in order to reduce the pressure to a point where capping is possible. The second move is the virtual ban, imposed by Secretary of the Interior Walter J. Hickel, on the use of DDT, aldrin, dieldrin, endrin, mercury compounds and nine other lesser known agents on vast areas of federal land. Thirty-two other chemicals and classes of chemicals will be placed on a restricted list allowing them to be used under limited circumstances, b u t only with the approval of the cabinet subcommittee on pesticides. The ban follows closely on the heels of an a n n o u n c e m e n t on 8 J u n e by the Olin Corporation, Alabama, that as from 30 J u n e it will halt production of DDT ('International Herald Tribune', 10 June). Three days earlier a suit had been filed in the Federal District Court in Washington by three conservation organizations asking that Olin, which produces 20 per cent of DDT manufactured in the US, be prohibited from discharging wastes containing DDT into water leading into the Wheeler Natural Wildlife Refuge in Alabama. Last, b u t b y no means least, as reported in 'Nature' (226 : 999; 1970)~ the signs are that the US Administration has accepted the recommendations of the commission under Mr Roy Ash on government organization that there should be set up an agency specifically concerned with the environment. Under the commission's proposals the agency would take over responsibility for water pollution from the Department of the Interior, for oil pollution and solid waste from the Department of Health, Education and Welfare, and for the regulation of pesticides from the Department of Agriculture. Programmes for the regulation of sewer systems could also be transferred to the new agency as could the work of the Food and Drug Administration. Apparently included in the commission's proposals is
one urging the setting up of an agency to be largely concerned with research and development in the environmental field.
Sewage Pollution affects Fish Increased discharge of chlorinated sewage effluent into the Little Patuxent River, Maryland, USA, between 1958 and 1967 caused changes in fish migration, abundance of resident species and the composition of the river's fish community. Changes in the n u m b e r of species and abundance of fish were most evident immediately below a sewage outfall. These findings, based on thrice yearly sampling at three stations along the coastal plain sector of the river, are described by Chu-Fa Tsai in a recent issue of 'Chesapeake Science' (11 (1) : 34 ; 1970). Two new sewage plants were constructed between 1958 and 1967 along the.sector of river examined, their discharges increasing substantially each year. During the same period the flow of the river was reduced by approximately 22 per cent. Tsai's analysis in 1967 was a repeat of that performed by Sanderson in 1958. Fish trapped at the three stations were removed, sorted and counted for three 10 day periods during April, June and September. According to Tsai the three stations represented areas with water of different quality. Thus station 1 upstream of the point of confluence of the Patuxent and Little Patuxent rivers was an area of little organic enrichment, without a decline in dissolved oxygen (DO) in the summer as compared with 1958 but with increased pH. Station 2, 13 km downstream of station 1 and only 270 m below a sewage outfall represented an area reflecting the direct effect of chlorinated sewage effluents, there being a decrease in June 1967 of DO and a general increase in the biological oxygen demand, and dissolved solids compared with 1958. Like station 3, 4.3 km downstream which also had a reduced DO content in June, 1967, station 2 was an area oF organic enrichment. Changes in water quality were reflected in the migration patterns and distribution of several migratory fish species. Thus the total catch of white catfish in 1967 was 257 compared with 312 in 1958. Together with white perch, white catfish was the dominant species at stations 3 and 2 during the spring spawning migration in both 1958 and 1967, b u t the abundance of the species was drastically reduced at station 2 in J u n e 1967. During the same period the number of white catfish increased downstream at station 3, which suggests to Tsai that upstream migration of the species was prevented b y the chlorinated sewage effluents concentrated at station 2 immediately below the sewage outfall. Similarly, the upstream migratory range of the potandromous white sucker and northern redhorse decreased between 1958 and 1967. The effects of sewage pollution on resident species were much greater. At station 2 there were fewer of each resident species in 1967 than in 1958, while at stations 1 and 3 the patterns of change varied according to the degree of tolerance to pollution, the habitat preference of each species and the amount of pollution. As regards the structure of the commtinity, at station 2 there were in total 82.7 per cent fewer individuals and 26.4 per cent fewer species in 1967 than in 1958. At stations 1 and 3 the number of species was fairly constant from 1958 to 1967, but the species composition changed significantly, probably due to increased organic enrichment and thus decline in DO content. These changes were greater during April and J u n e than during September, chiefly as a result of the changes in population of the dominant migratory species.
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