Document 3NzEZ6DOVO1vD18VGKw8p73aJ

NATURAL HISTORY MAGAZIN November, 1971 The discovery of birth deformilieo among the term on Creel Cull Ielend we* due largely to the effort* of Helen Have. Aided by crew* of volunteers from The American Mueeum, ehe ha* been studying the colony in Long bland IF YOU DONT KNOW what charcoal mellowing does Sound since 1966. Chairman of the Creal Gull Island Gommiiiee of the for Jade Daniel's, we'd suggest a calk with Herb Fanning. Museum'* Department of Ornithol ogy. Hay* ha* also studied ruddy Herb was the jack Danid purchasing agent for thirty ducks in Manitoba. Canada: Ibias* and herons in Jamain* Be*. New yean. So you can be sure he knows his whiskey. York: and term in North Carolina. She holds a B.A. in And hell tell you there's no better from Wellesley College and au way to make it than with thored "The Adaptive Ibto" in the charcoal mellowing, the ancient CHARCOAL MELLOWED method Jack Daniel invented a 6 century agp. Alter a chat with DROP Mr. Fanning, you11 agree he's a 6 pretty good convincer. But then, BY DROP so is a sip of Jack Daniel's. rtaattitt gau...m......m Moor av enoict i--- tm. ttruiti nt soTHi* st iaca **nui aitnutai itecniiiii <rt% >. Ttan MONS 206924 Ctntnuuxi 0 The ultimate African adventure. Spend an unforgettable 39 days luxuriously touring from Capetown into the heart of breath taking East Africa Your group, limited to 25, will tour in special air-conditioned fivepassenger vehicles with a window seat for each member You'll enjoy personal care and attention.The limited membership also will al low tor such pleasures as a la carte dining, special events and visits to private homes and small villages. You will travel through South Africa, Rhodesia. Kenya, Tanzania, Uganda Stay at luxury hotels like the world-famous Treetops, the Mt Kenya Safari Club and the new Paraa Safari Lodge, overlooking the Nile. But best of all. you will experience the incomparable physical beauty of Africa Such spectacles as the breathtaking beauty of Victoria Falls The Ngorongoro crater. The majesty of Mt Kilimanjaro, and the incredible variety of wildlife, gazelle, zebra, wildebeest, rhino, I ion, and elephant But this small advertisement can't do justice to the sights and sounds of 39 magnificent days of beauty,wildlife, deluxe accommoda- tipns and transportation. There an 14 departures. In elf, only 350 people will be able to take this ultimate journey. Be one of them Send for our free brochure. August'September, 1967, issue of Natural History Magazine. Coauthor snd investigator with Hays of the developing Crest Cull Islsnd trsgedy, Robert W. Risebrough is an associate research ""ecologist with the Bodega Marine Laboratorv of the University of Cal ifornia He has conducted field work in the Indian Ocean, South east Asia, Latin America, the Galipagos, Antarctica, and the Cana dian Arctic. Risebrough. a native Canadian, has a Ph.D. in molecular biologv from Harvard University. He plans continued research on the effects of pollutants upon birds and marine ecosystems, including the terns in Long Island Sound. A more detailed report on the deformities discussed by Hays and Risebrough will appear in a forthcoming issue of The Auk. William A. Dunson. associate professor of biology al Pennsylvania State University, has done much of his work on sea snakes aboard the Alpha Helix, research vessel of the Scripps Institution of Ocean ography. His investigations have concerned the successful adapta tions of snakes to a marine environ ment and the reasons that other reptiles are not as numerous in the sea. He is planning a sabbatical next year during which he will study the physiological ecology of sea snakes at the Australian In stitute of Marine Science. Dunson earned his Ph.D. in zoology at the University of Michigan. Charles E. Adelsen, author of "The Road to Ani." has teamed with photographer Henry AngeloCastrillon for eleven vears to re port on eastern Turkey in European media. This article is the result of their second trip to Ani in seven years, during which thev found travel restrictions eased and mili tary commanders far more relaxed about tourists. Ani is still not easv to get to, though, they add. Belgian World Airlines. Sabena BelgianWtortd Airlines 720 Fifth Avenue New York, NY 10019 NH Please send me information on the Sabena Cape to Kampala tour. Name,,__________________ .. Address________________ Car----------------- StaleZip----- . Mr travel agent Is HONS 206925 The Early Warmim of the Terns Thousands of terns have replaced the Army on an Island fortress originally designed to detect an enemy Invasion of New York. The enemy has now arrived, and a major ornithological disaster may be upon us by Helen Hays and Robert W. Rlsebrough Great Gull Island is a small, un* inhabited pile of rocks, clay, and shifting sands at the entrance of Long Island Sound between the eastern tip of Long Island and Con necticut. Because of its strategic lo cation, for half a century the taland served as part of the defense system of the nation; today, the striking in crease of birth-deformed birds there may be a warning of a new and more insidious danger. The islsnd is an excellent habitat for terns, small members of the gull family that nest on isolated coasts end barrier beaches throughout the world- To survive in these tem pestuous sreas of winds, tides, and shifting sands, the terns have to be adaptive and sensitive to change: always shifting, colonizing newly formed habitats, or quickly desert ing old ones as they are destroyed by the elementa or by man. Nearly s century ago, when the rapacious millinery trade in its pur suit of feathers for fashion threat ened the survival of terns on the East Coast, conservationists pro vided a warden on Great Gulf Is land to save the birds. The 14,000 terns on the islsnd became the last nesting colony, the last hope for terns in the New York region, as other colonies on Long Island Sound were wiped out by plume hunters and eggers. Shortly after 1900, terns became a protected species when a pioneer ing piece of conservation legislation was passed in the United Stales. But, ironically, the legislation came too late for the terns on Great Gull Island, for in 1897, on the eve of the Spanish-American War, fearing attack by a Spanish armada, the United Stales government had be gun the construction of Fort Mkhie on the island. With the arrival of the military, the terns disappeared. In the following decades, the shadow of war rarely lifted from Great Gull Island. During World Wan I and II, the military used the island for its continental warning and defense system. From tall ob servation lowers, soldiers scanned the ocean, alwavs alert to the dan- !;er of attack. Over the yean, the ort became a complex maze of gun emplacements, ammunition depots, barracks, and towen. By the end of World War II, the island was al most completely covered with con crete and asphalt. And the terns avoided this unnatural transforma tion of their former habitat. Then, in the late 1940's, Fort Michie lost its function in the warning and defense system for the Continent. It became a symbol of obsolete military equipment and strategy, and in 1949 the Army abandoned the island, leaving be hind its concrete and asphalt, junkpilea, man-made hills, and necklace of traprock boulders placed around the island to stabilize its shores. Although man was gone, the habitat was too disturbed for the terns to return. Yel by the late 1940's, the terns of Long Island badly needed a new breeding area; the old protective legislation was no longer adequate to save them from new devel opments. The encroachment of fac tories and housing developments in coastal areas, along with the con version of beaches to public parks, drastically reduced the number of undisturbed nesting areas for terns in the New York region. Aware of the island's history. The American Museum of Natural History and the Linnaean Society of New York worked to acquire Great Gull Island, hoping that it might again become a large colony for nesting terns. In 1949, the Museum received title and assigned to the Linnaean Society the task of return ing it (o a condition suitable for terns. In 1949 and 1950, several of the buildings were leveled, vegetation was burned, and sand was deposited in an effort to create artificial beaches. Each year the island was visited by ornithologists from the Linnaean Society ana the Museum, but if was not until 1955, after ev eryone had given up hope that the HONS 206926 / < 39 > bird* would ever breed there again, that twenty-five pair* of common ternB were found nesting. Hie birds had not utilized any of the areas prepared for them, but had laid their eggs on the traprock at the eastern edge of the island. The numbers of terns increased each succeeding year and today, once again, the island is the site of one of the largest colonies in Long Island Sound, comprising about 7,000 birds. people how land on the island in late spring or early aummer, the terna swirl noisily from the ruins of the fort, challenging the in truders and diving at them ahould they approach the nest aites. Re minders of the island's occupation hy the military still remain every where. The rums of the altandoned fort, overgrown with vegetation, stretch from one end of the island to the other. The battlements are manned, however, by new defend ers. On patches of exfoliating con crete in the gun emplacements and in the open areas that were once building foundations, common terns incubate their eggs and feed and brood their youngTrhe roseate Chemical pollutants, such aa PCB'a, are highly suspect as the cause of an alarming increase in gross birth terns, less aggressive than the com deformities among the mons. deposit their eggs in the grassy edges of the open areas or under boulders on the outer beaches. Their utilization of the ruins of terns on Great Gull Island. This four-legged common tern chick, died three days after hatching. the old fort on Great Gull Island demonstrates the tern's remarkable adaptability and use of habitat, a previously unknown characteristic of the species. A number of other apecies also occupy parts of the ruins Barn Bwallows dart in and out of the weathered buildings, patching them with mud for their nests, fiayberry and wild rose, as well as several species of grasses, have invaded the ruins, making them habitable for nesting red winged blackbirds, song sparrows, and spotted sandpipers Starlings also nest in the eaves of buildings. By 1966, the colony appeared sufficiently large and stable to per mit ornithologists from the Museum ' to undertake studies of the breeding biology of both species of terns, as well as of severs! of the other spe cies nesting on the island. During the summers of 1967 and 1968, however, there was a great deal of rain and a scarcity of fish. HONS 206927 40 Still (training to fly after fourteen weeks, the abnormal common tern, right, can only manage to rise a few feet. It had the double misfortune of being born without secondary flight feathers in a nest built within the insurmountable rim of a huge gun emplacement. It is doomed in this concrete enclosure. The fate of the five-weekold chick, far right, is similarly sealed: it was born without tail feathers, primary, and secondary flight feathers. Fort Michie'a ruins, below, still dominate the landscape. ' , ,t 1 m.\ I Iiipyp _i I i I i ,e*is<wsMamt<aBSiiiisil^StrtSSttrtiMI^ 4* li r \* ' , yjtfiH*, .* * s' / " 1 v',-'1 MOWS 206929 r Many young terns died from ex* and marked with temporary plastic t .i posure, starvation, or both. A major bands. Of these, one young com Eroblr-m in the held of population mon tern was found with an abnor 1 iology is determining the produc mal bill and an upper mandible ' i tivity of a species under a variety of crossed over its lower. Then, two i environments) conditions, favorable young roseate terns were found, I and unfavorable. The colony on which appeared normal, bui which Great Gull Island appeared to be an were missing flight feathers in both appropriate site to study this prob wings. We noted these deformities, lem in relation to terns because the but the flight feathers of the rose- island's sice, seventeen acres, was tea appeared to be growing again small enough to permit a daily In a sample as Urge as 2,000 indi checking of all nesting areas. viduals, s few abnormalities are to Daily coverage of the nesting be expected, and we did not attach grounds permitted large numbers of special significance to these. young terns to be marked at hatch ing, men followed with relative ease up to the time of fledging and de parture from the colony. Studies of survival and mortality of both spe cies of term were begun in 1969. The number of field workers in creased each weekend with the arri val of volunteers from the Museum. ITo avoid exposing the mgs and the young terns to the midday sun, all n 1970. however, when the study work in the colony was carried out was repealed, we noted a sharp in whenever temperatures were favor crease in the number of abnor able, usually in the early morning malities. Four young roseate lerns or late afternoon. The terns in and thirty-three young common variably put up a vigorous defense. terns were found with visible de Working in a tern colony ia strictly fects. Some of these appeared nor a "hard hat" job, aince the terns do mal at the lime of hatching, but not hesitate to atrike unsuspecting later, when they were between two heads with formidable force ana and four weeks old, lost their pri very sharp beaks. Usually several mary and secondary flight feathers. workers would traverse an area to Feather loss is a new phenome gether, looking for new nests and non that hat not been previously young birda. At hatching in 1969, more than 2,000 young term were examined described, although in the past many thousands of terns have been bawled in Massachusetts, the Garth- HONS 206930 43 Crossed mandibles were discovered in ihe colony in 1969, the tint full year of the research project. This roseate tern chick, from the 1970 breeding season, was collected when three weeks old for chemical analysis of its tissues. bean, and on islands in the Pacific. Although these birds appeared to be healthy and vigorous, they could not fly. Two lived as long as six weeks Many disappeared, however, so complete observstions of their mortality rate were not possible. The feather loss did not seem to be necessarily permanent, as one of the young common terns found with no primary and secondary flight featners was seen flying month later at Milford, Com necticut, about 80 miles sway. Other abnormalities were com* parable to thoae observed in human ''thalidomide babies." One chick had underdeveloped leg. and feet / with almost no down, and another had four legs. Several showed ab normalities in the development of the bill. One chick had extremely small eyes. It was at this time that the au thors combined forces and ex perience in an attempt to determine the causes of the abnormalities. Our suspicions centered on environmen tal pollutants in Long Island Sound, the flush for much oT the effluvia of New York and Connecticut. An in vestigation of this type, however, encompasses many different dis ciplines, and only detailed studies, over a period of time, will teD us what is actually happening to the population structure and reproduc tive capacity of the species affected by pollutants. In order to identify the pollutants that might be respon" sible for the abnormautiea observed in the field, complex research in the produce shell-thinning under ex chemistry laboratory is also neces perimental conditions in mallard sary. Thr studies during the present year, therefore, were carried out durks, American kestrels, quails and doves Wild species that ire with the realization that we were dealing with a new kind of enemy suffering from the thin eggshell syn drome hive also been found to be force, far different from the ravages of the plume hunters or the destruc contaminated with DDE. The DDT levels we measured in tion of breeding sites This enemy the abnormal young terns on Great foreshadowed grave consequences for the future of the terns and quite Gull Island and in the fish brought to the colony by the adults in 1970, possibly for man himself, There was however, were no higher than in no douhl that we were looking at ma.iy other bird populations. In the tip of potentially disastrous fact, they were lower than some. iceberg. While we have no basis for believ This year's incidence of gross de fects among newly hatched chicks ing that any of tbe DDT compounds re responsible for the observed de was approximately comparable to formities in the young terns, we that in 1970. The first to be found -cannot rule it out as s possible had an abnormal foot and leg. The cause of shell-lhinmng, This was second had rudimentary upper not observed until 1971, and we mandible, which had grown out hsve not yet measured DDT levels from above its eyes. The third ap in the 19/1 specimens. peared as if injected with an- or wa Levels of other heavy metsls, ter; its skin was swollen about the such as lead and cadmium, ire cur head, neck, and abdomen. The rently being measured, but until fourth had no left eye and a slightly much more data from other popu crossed bill. Three others had bald lations are accumulated, we shall spots on their bodies where feathers not know what the expected natural had not developed. The loss of levels of these elements in tern eggs flight feathers was again observed should be, or how to interpret the tn many of the chicks. These are concentrations found. the kinds of effects that might be expected from a chemical capable of affecting gene reproduction dur ing embryonic cell division. Added to this, in 1971 a new ab normality was observed in the col ony for the first time; thin-shelled eggs not sufficiently strong to sup port the weight of tbe incubating Wkparent. This phenomenon is now fa miliar to pollution biologista, hav hat we did find were rela ing been first reported in British tively huh levels of polychlorinated peregrine falcons in the 1950s. biphenyls, PCB's, in the tern tissues The urown pelicans in California and in the fish upon which thr birds have not bred auccessfully for a feed. These compounds have a number of years because of this number of chemical properties sim problem, and some of the birds of ilar to DDT. Like DDT and its de prey in this country are suffering rivatives, they become concentrated serious population declines for the in the fatty tissues of animals when same reason. present in a food chain, but they Researchers in this area believe are even more stable. Used exten that shelf-thinning is caused primar sively as heat-exchange and in ily by the DDT compound, DDE. sulating fluids in high-voltage elec This pollutant, a derivative of the trical equipment, PCB's are also insecticide, is only slightly poi added to paints, plastics, and rub sonous to most individual organ ber to make these materials more isms, but it may produce such ef resistant to breakdown. This prop fects as shell-thinning, which lowers erty of-resistance to most kinds of the reproductive capacity of the biological and chemical degrada apeciet. DDE has been shown to tion, which hat made them so use 4 HONS 206931 45 > ful to industry, are whml make PCB's such persistent pollutants when released in the environment. Intcrestinglv, in some of the studies in which PCB's were fed to birds in order to determine toxic effects, the birds lost feathers. The FCB'a may well, therefore, be responsible for the feather loss observed in the voung terns on Great Gull Island. Recent research conducted in the Netherlands has demonstrated that PCB preparations often contain small concentrations of compounds that are chemically similiar to the extremely toxic dioxins. These are -the chlorinated dibenzofurans, and the relationship is significant be cause these dioxins have produced a high incidence of birth defects in recent experiments. Smalt amounts of the chemicals were injected into fertile chicken eggs, producing grossly deformed chicks of the same type we have observed in the young terns. Obviously, much further re search is necessary before we can definitely pinpoint just what pollu tants are responsible for what defor mities, and what the cause-and-effeet relationships are. It it important to point out that al though all the evidence ia not yet in and weighed, what ia happening to the terns on Great Gull laland of critical significance--not only to the local survival of the species, but quite possibly to humans as well. We might hypothesise that the effects of environmental pollutants, auch as those mentioned, would be delrcled first in the tern colony. Long Island Sound is one of the more polluted areas of the world's oceans, a distinction it shares with the Baltic, the Mediterranean, and the southern California coastal wa ters. And the effects of chemical pillutanis could be expected to ap pear first in a species that is rela tively high on the food chain, e*[H`cially one that preys upon fish, 46 Not all the pregnant women who ingested thalidomide gave birth to defective children. Rather, the in cidence of defects was significantly increased. We could assume that environmental chemicals producing comparable effects would behave similarly and that their presence would not mean that all individuals would be equally affected. A nor mal-looking individual might have a higher concentration of certain pol lutants lhan one with four legs. Consequently, many thousands of young must be examined to detect the first effects of pollutants build ing up in a population of any spe cies. it is probable that as the levels of harmful pollutants increase in a population, more individuals will show adverse effects. But only con tinued work will verify this. In addition, high priority should be given to a deiailed study of the pollutants now present in the wa ters of Long Island Sound. All of these, we must emphasize, are waste products. Normally, the waste prod ucts within an ecosystem are re cycled, used again and again. Thus the tissues of a dead bird gradually are converted into elementary mate rial. Carbon dioxide re-enters the atmosphere to participate once again in photosynthesis. Phosphates re-enter the water to be in corporated once agsm into phyto plankton, from which they pass into zooplankton, then up the food chain through fiah lo terns, and so on. Technological man has made two fundamental changes in this natural process. By mining vast amounts of certain heavy mr.lals and salts, such as phosphates, the mobilization has been greatly increased. When these become waste products in excessive amounts, the threshold of harm to certain species is passed. Also some of the new synthetic chemicals are relatively resistant to breakdown, and so more readily build up to concentrations harmful to a great many more species, If our priorities are rearranged to meet the mounting environmental and biological crises caused by the exploitation of natural systems, suf ficient warning will lie milled to provide lime to ihange our tech nological (lircd ion and commoment of natural resources, We Boulders dumped by the Army to prevent erosion cover the island's shoreline. It was thought that this ruination of habitat would prevent the terns from reclaiming their lost colony, but they have adapted and now nest in the network of rocks. have had such warnings about air pollution, sewage in our waterways and lead poisoning, for example, and some measures are being taken to correct these threats lo human health and well-being. Now the terns on Great Gull Island are is suing a warning through ihrtr piti ful deformities and threatened sur vival. That seventeen-acre island that is home to the colonv occupies a strategic position analogous to when it served as a military outpost. The terns occupying the approaches to New York Qly are now inadvert ently detecting a newer, more in aidioua enemy to man: con taminants. Presentlv disturbing ihe reproduction of the terns, these contaminants mav, soinedav soon, result in an increase in the numbers of human birth defects as thrv work up through the food chain 10 the ul timate consumer. Fort Michte. now in ruins, mav vet provide us with an early warning against encroaching danger. At sue go to press, vertfed re ports of significant feather loss among chicks tn tern colonies in Massachusetts1, Jones Beorh, New York: and the Dn Tortugas. off" Florida, have been recrived. The scape of the disaster is broadening. HONS 206932