Petroleum Industry's Role in Marine Bird Conservation

Keith G. Hay

American Petroleum Institute
2101 L Street NW
Washington, D.C. 20037

Abstract

Despite improved safety practices, engineering, and navigational skills, marine tanker transportation will not be 100% accident free. The industry seeks to mitigate wildlife losses through improved technology, research in the rehabilitation of species exposed to oil, and the development of oil spill/wildlife contingency plans.

Oil spills and marine birds not only constitute a deadly mix but have proved to be one of our toughest environmental problems to solve. The rehabilitation of these tragic victims is plagued with controversy, emotion, apathy, and biological unknowns. The costs have been high and the survival rates low. During the last 10 years, a few dedicated people working here and in Europe have reversed this trend. They have, in addition, taken steps to develop contingency plans and conducted research to reduce seabird mortalities from oil spills. I present a brief status report on their progress and the melange of problems involved.

The unfortunate encounter between spilled oil and marine birds is not new. It goes back at least to the turn of the century, when coal-burning steamships and sailing clippers were replaced by oil-fueled vessels. Since then thousands of marine birds have succumbed to floating oil, especially during World Wars I and II (Blanks 1942) and in recent spills here and off the coast of Europe (Clark 1969).

With the current and projected demands for energy in the United States and with expanded tanker traffic and accelerated development of offshore petroleum reserves, the oil-contaminated ("oiled") bird is not going to go away. Periodically, this ugly problem will arise, despite the efforts of the petroleum industry to improve its safety practices, engineering, and navigational skills. Unfortunately, the problem is the product of the inherent fallibility of man and his imperfect machines.

We cannot ignore the situation. We must here, as elsewhere, improve our technology and mitigate the impact.

A study of more than 100 spills that occurred throughout the world between 1960 and 1971 revealed that about 1 in 5 spills (20%) involved 50 or more birds (Ottway 1971). Nearshore spills have a far greater effect on waterfowl than do spills occurring several miles or more offshore.

In the 1967 Torrey Canyon tanker spill, some 8,000 oiled birds were rescued. About 6,000 were picked up alive in England and about 2,000 in France, at a cost estimated at $160,000 (Clark 1969; Bourne 1970). Less than 5% of those treated by British authorities survived for release some months later. The survival rate of those rescued in France is unknown.

In 1969 the Santa Barbara spill resulted in the treatment of 1,575 marine birds, of which 169 were eventually released. Many of those released were found dead within a short time (Smail 1971).

In 1970 the tanker Delian Apollon was responsible for a spill in Tampa Bay, Florida. Thousands of seabirds were lost. No exact count was taken, but hundreds of birds were cleaned and farmed out for rehabilitation. Reports show that many of the birds were returned dead within a few days (Smithsonian Institution 1971).

In 1971, when two tankers collided under the Golden Gate Bridge at the mouth of San Francisco Bay, the resulting spill involved some 4,686 oiled birds taken to cleaning centers (Lassen 1972). Eight months later the last of 200 survivors (less than 5%) were released at a cost estimated at $900 per bird (Smith 1975).

The most vulnerable species involved in spills have been the oceanic birds such as the alcids—murres (Uria spp.), auks (Pinguinus spp., Alca spp.), puffins (Fratercula spp., Lunda spp.), and guillemots (Cepphus spp.). Other species less affected included ruddy ducks (Oxyura jamaicensis), scaup (Aythya marila, A. affinis), scoters (Melanitta spp.), mergansers (Lophodytes spp.), oldsquaws (Clangula spp.), and goldeneyes (Bucephala spp.). Grebes (Podiceps spp.), eiders (Polysticta spp.), loons (Gavia spp.), and cormorants (Phalacrocorax spp.) are also frequently involved. Ruddy ducks and scaup are particularly vulnerable during winter on large river systems with heavy oil transport traffic. Fortunately, none of the above species have been reported in jeopardy as a result of spills in American waters.

In Europe and South Africa, however, it is believed that oil pollution is responsible for a steady decline in seabird colonies. For example, in known oil-dumping areas in the Baltic Sea, where some mortality of oldsquaws has been associated with surface oil, their population has dropped to about one-tenth of the pre-World War II level (Bergman 1961). Other authors report that oil spills have reduced the number of scoters in the Baltic and off southeast England (Atkinson-Willes 1963). The auk populations off the coast of England have been reported to be substantially decreased by oil pollution (Parslow 1967). Tankers traversing South Africa's Cape of Good Hope are said to be responsible for the reduction of jackass penguins, Spheniscus demersus (Rowan 1968). Oil pollution, especially sustained pollution, has thus been cited as a limiting factor on certain seabird populations.

Estimates of seabird mortalities from an oil spill are imprecise; they may differ by thousands of birds. It is believed that only a small fraction of the birds killed in a spill wash up on the shore. Some authors have even speculated that the death rate at sea could range from 6 to 25 times the number washed ashore (Tanis and Mörzer-Bruyns 1968).

In contrast to terrestrial birds and semiaquatic species (e.g., ducks; geese; coots, Fulica spp.; or gulls, Larus spp.), totally seaborne species have a restricted reproductive potential. Many, such as the alcids, do not breed until they are 3 or more years old, and lay only one egg per year. Only one in five survives to go to sea.

Until about 5 years ago we knew little about seabirds. They are not game species (they taste fishy) and thus do not constitute an important economic resource. They have never been the subject of intensive waterfowl management or research by either State or Federal governments.

During the last 5 years a small group of people here and in England have been studying marine birds—their distribution, population status, physiology, diseases, and husbandry in captivity. Four organizations have primarily been involved: The American Petroleum Institute (API); the Wildlife Rehabilitation Center at Upton, Massachusetts; England's Advisory Committee on Oil Pollution of the Sea; and the International Bird Rescue Research Center in Berkeley, California. They have encountered many common biological and people problems, some of which I discuss here.

Biological Problems

The recuperation record for oiled seabirds in the past has admittedly been dismal. A few birds have been returned to nature, but only after a long and costly period of care. In the process, semidomestication often takes place. The percentage of cleaned birds that actually survive after release is even smaller. One should not infer from this small percentage that rehabilitated birds cannot readjust to life in the wild. Several successful reintroductions have been documented. U.S. Fish and Wildlife Service bands were returned from two western grebes that were cleaned and released after the 1971 San Francisco spill. One bird was picked up a year later near Treasure Island, California, and the second after almost 2 years, in the State of Washington (Fletcher 1973).

Survival rates have zoomed with recent strides in cleaning technology and husbandry. The International Bird Rescue Research Center reported a survival rate of 41%, based on hundreds of birds and about 20 different species over a 2-year period (Smith 1975). In South Africa, where powdered clay was used as a cleaning agent on jackass penguins, nearly 50% survived, although exact percentages have not been published (Edwards 1963; Holmes 1973). Rapid retrieval, the relatively small groups of birds treated, and expert cleaning and husbandry techniques are largely responsible for high success ratios. Rehabilitation success is measured not only in terms of percent survival but also in terms of median length of captivity and average cost per bird.

Rescued oiled birds arrive at cleaning centers under a wide range of physical conditions. Before capture they may have spent hours or days in water, during which their energy has been continuously drained. The oil destroys the bird's protective insulation, and metabolic rate must be increased to sustain body temperature. Constant preening also takes energy. Food demands increase, but feeding attempts, especially for diving birds, are thwarted by oil-fouled plumage. A bird may arrive at the cleaning center under stress, chilled, exhausted, dehydrated, starved, and ill from ingested oil. Cold weather accentuates these conditions. Often such birds are jammed together with other species, hauled long distances, and immediately put through a series of cleaning processes that would leave even a healthy bird weak and in a state of shock. One marvels at the stamina of the survivors.

In most past spills, every bird found was routinely cleaned regardless of its condition. Instead of attempting to reclaim all birds, a selective judgment should be made. If a bird's physical condition makes its chances of survival nearly impossible, it should be humanely killed (except for rare or endangered species). This would enable workers to devote more time and care to birds having a reasonable chance at survival.

Fletcher (1973) stated that many variables affect bird survival: weather conditions, the type and amount of oil in and on the bird, the species, the distance of the spill from the shore, the time lag from initial fouling until initial treatment, the degree of stress a bird is subjected to, the husbandry techniques used, the time of release (the sooner released, the higher the apparent survival), the number of birds being cared for (the fewer birds being handled, the higher the survival rate), the quality of the facilities available, and the training and experience of the people handling the birds.

Many of the above biological problems are under study here and in Europe, including the following.

• The effect of ingested oil on the mucosal transport mechanism of marine birds. To use seawater, birds must be able to transport sodium ions through the gut and expel the excess salt through the nasal passages. Oil can block the mucosal ion transport mechanism, resulting in dehydration and eventual death.

• The development of a successful program of hormonal and electrolyte therapy to restore osmotic balance and the functioning of the salt glands in contaminated seabirds.

• Treatment and prevention of aspergillosis (fungus infection); septic arthritis or "bumble-foot" (joint capsule infections); breast sores (especially in seabirds confined on hard surfaces); eye lesions (caused by ammonia fumes from unsanitary pens); dehydration and hypoglycemia; lipid pneumonia; and bacterial infections.

• Treatment of stress after capture, including perfection of handling and cleaning techniques, administration of proper steroids, crowding, light, temperature, noise levels, and so on.

• Development of proper nutritional regimes for certain species and feeding techniques to eliminate forced feeding.

• The establishment of criteria for confident recognition of terminal pathological conditions in oiled birds.

• Determination of optimum density of confined birds to insure healthy conditions and adequate room for preening.

• Determination of proper time and conditions for reintroduction of the birds into their native habitat.

People Problems

Handling an over-responsive and emotional army of bird-cleaning volunteers and training them to play constructive roles is a major undertaking. Planning, cooperation, understanding, patience, and clear direction must be developed. In the absence of these virtues, chaos can and has prevailed.

The San Francisco Bay oil spill of 1971 was a classic example. There was virtually no State or Federal coordination. Splinter groups of volunteers established their own "treatment centers" and jealously guarded their patients. Some actually absconded with their pet patients to seek better care elsewhere. Long hours, fatigue, and frustrations led to dissension and bitter quarrels. Antiestablishment sentiment was rampant.

Instant experts on bird cleaning, avian medicine, and nutrition appeared or developed overnight. Veterinarians volunteered their services, but their knowledge of oiled-bird treatment was limited. A wide variety of food (from canned dog food to live shrimp) was given the birds. Forced feeding was routine. Medications and vitamins of all kinds were also administered. Needless to say, the states of the art in treating oiled birds and handling volunteers were both in their infancy. For both, the success ratio was near zero.

To prevent such fruitless efforts and the frantic, unorganized response that prevailed, a well-designed contingency plan for wildlife involved in an oil spill is needed.

Contingency Planning

It is only prudent to take reasonable measures to prepare for oiled-bird emergencies. This is especially true in regions where bird concentrations and oil shipment traffic converge. Almost equal attention must be devoted to handling volunteers as to handling birds. Safety is a major consideration. The sharp beaks of birds can be very dangerous.

A model State contingency plan should include the following:

• A list of State and Federal agencies to be alerted, including 24-h, 7-day-a-week telephone numbers, and names of individuals to contact.

• Clarification of the roles of State and Federal agencies under the Regional Response Plan of the National Oil and Hazardous Substances Pollution Contingency Plan.

• A list of State and Federal laws pertaining to possession of birds and mammals.

• An updated roster should be maintained of team members, assignments, and responsibilities for inland and marine spills, including discovery and notification, record keeping, public information, containment and counter-measures, wildlife protection, and cleanup, restoration and evaluation of effects on the biota.

• A list of individuals or organizations that possess skills and experience in treatment of oiled birds (locally and nationally).

• Location of emergency wildlife reception and treatment centers.

• A list of the necessary supplies, equipment, and holding facilities for cleaning, treating, drying, and post-care operations. Such information can be obtained from:

—California Department of Fish and Game, Oil and Hazardous Materials Contingency Plan (July 1974)

—International Bird Rescue Research Center, Aquatic Park, Berkeley, California 94710

—American Petroleum Institute, 2101 L Street, Northwest, Washington, D.C. 20037

—Wildlife Rehabilitation Center, 84 Grove Street, Upton, Massachusetts 01568

• An organizational plan which includes assignments of duties and responsibilities for personnel manning a bird-cleaning center. In addition to bird cleaning and husbandry, assignments must be made for record keeping, internal communications, public relations, logistics (supplies), security, sanitation, safety, and meals.

• A slide lecture or film to instruct volunteers in the correct techniques for handling, cleaning, and post-care of oiled birds.

• A selected bibliography of key references on oiled-bird cleaning and care.

• Appendices to the plan should include maps of the major coastal oil terminals, bays, and estuarine areas with heavy oil transport traffic. Map overlays would depict the location of resident species and the migratory patterns, species composition, relative abundance, and winter concentration areas of migrants. Additional overlays would locate commercially important demersal seafood areas (e.g., oyster and abalone beds, lobster and crabbing locales) and marine mammal habitats. Further refinement of an atlas could include information on tides, prevailing winds, ocean currents, and water mass movements to assist in predicting the path of spilled oil.

What Has Been Accomplished

The petroleum industry, through the API, took prompt steps to mitigate the problem after the first seabird mortalities were reported from Santa Barbara in 1969. They commissioned a young aviculturist, Philip Stanton, who has extensive experience working with wild waterfowl, to start a research program on cleaning and caring for oiled birds. At his Wildlife Rehabilitation Center at Upton, Massachusetts. Stanton, with the help of API, has been conducting research on oiled birds for 7 years. He is also an assistant professor of biology at nearby Framingham State College. Stanton's studies (unpublished) include investigations on food shape and color preferences in wild ducks, the effects of lengthened photoperiods on breeding of arctic geese, and the effects of diets of varying protein concentrations on growth and development of the common eider duck.

As a result of his research on cleaning techniques and agents, Stanton has recommended a nontoxic liquid cleaner called Polycomplex A-11. Although not perfect, it is one of several cleaning agents being successfully used today. He has authored a "how to" guide for oiled-bird treatment entitled "Operation Rescue" and prepared a companion bibliography (Stanton 1972). These booklets have been distributed throughout the United States to State and Federal agencies and conservation organizations. He has provided consulting services at numerous spills and has worked to establish oiled-wildlife treatment centers in coastal States.

Since 1972 the API has sponsored an avian physiology study at the University of California at Santa Barbara. Under the direction of W. N. Holmes, the studies are directed at the effects of ingested crude oil and petroleum products on marine birds. Holmes has revealed that small quantities of crude oil introduced into the gut of a saltwater-adapted bird can affect the mucosal transport and extra-renal excretory mechanisms, resulting in acute dehydration and eventual death. Dr. Holmes is also examining the effects of the various distillation fractions derived from crude oil and the long-term effects of ingested oil in mature birds. Incidentally, Alaska North Slope oil was found to be almost innocuous when administered to ducklings in amounts similar to the effective doses of other oils (Holmes and Cronshaw 1975).

Refined products (diesel oil, No. 2 fuel oil, and Bunker "C") are known to be more toxic than crude oil. For example, the relatively small spills of Bunker "C" at Tampa, Florida, in 1970 and in San Francisco in 1971 caused approximate mortalities of 90 and 20 birds per ton of spilled product, respectively. The crude oil spills of the Torrey Canyon and at Santa Barbara, however, resulted in mortalities of only 0.5 and 0.6 bird per ton of oil (Clark 1973).

Dr. Holmes is now testing measured amounts of the above refined oils on adult birds. He is determining the degree of dehydration incurred, the resulting pathological changes, and the replacement (hormonal and electrolyte) therapy necessary to rehabilitate the birds.

It is obviously important to keep as many birds away from an oil slick as possible. This was the objective of an API contract with the Av-Alarm Corporation of Santa Maria, California. Their objective was to determine the feasibility of repelling aquatic birds from an area by using an acoustical jamming device as the stimulus.

The flocking instinct in birds provides mutual protection through their almost constant communication with one another. When this (audio) communication is prevented by jamming with high-frequency sounds, the birds immediately leave the area to seek relief. This harmless technique has been used successfully for years to repel agricultural pest birds.

The Av-Alarm device was tested on waterfowl at the Grizzly Island Game Refuge some 48 km north of San Francisco Bay and in the bay itself over a 2-year period (1972-73). Using a single, fixed-location system covering a three-quarter square mile (1.21 km²) area Crummett (1973) repelled 82% of the ducks and 92% of the shorebirds on the Refuge. The intrepid coot, however, was found to be relatively indifferent to the sounds. Immediately upon activation, there was a sudden drop in the bird count, which was followed by a continual decline in numbers.

In tests of the device from a cruising boat in ocean and bay waters, the degree of effectiveness varied by species. Ducks were repelled 100%; pelicans (Pelecanus spp.) 92%; great egrets (Casmerodius albus) 85%; gulls 42%; cormorants 75%; shearwaters (Adamastor spp.) 29%; and murres, 51%.

Grebes and murres dived away from the stimulus, then surfaced and dived again if the threat was still present. To prevent driving the diving species deeper into the center of a slick, investigators recommended that buoyed repelling equipment be placed within the spill area. When the alarm system was used in conjunction with the occasional firing of a rocket or shellcracker, an even greater percentage of birds was repelled.

The International Bird Rescue Research Center, a nonprofit corporation in Berkeley, California, was an outgrowth of the Richmond Bird Care Center that played an active role in the 1971 San Francisco Bay spill. Since that time, a small group of individuals has continued research on bird-cleaning techniques, testing cleaning agents, perfecting husbandry methods, and alleviating stress. Their 41% survival rate speaks for itself. A paper describing their work is being presented at this conference (Smith 1975).

Under a grant from the API, the center is currently evaluating various cleaning agents, and testing the pressurized jet versus serial baths and the re-establishment of feather waterproofing. The center is also perfecting an audio-visual slide presentation that will illustrate how to select the proper cleaning agent, together with the latest bird-cleaning and care procedures.

About 5 years ago, England's Advisory Committee on Oil Pollution of the Sea established a research unit in the Department of Zoology at the University of Newcastle-Upon-Tyne. It was funded by a grant from the Royal Society for Prevention of Cruelty to Animals, the Royal Society for the Preservation of Birds, the World Wildlife Fund Seabird Appeal, and the British Institute of Petroleum.

Their efforts have also led to high survival rates. Focusing primarily on the efficiency of various detergents, they have found that the loss of waterproofing is largely due to soap and oil residues and the disturbance of the feather structure in the cleaning process. Consequently, they have devoted their efforts to selecting detergents that can be completely removed with a minimum disturbance of plumage (Seabird Research Unit 1971).

In May 1974, the API in cooperation with the U.S. Fish and Wildlife Service convened a seminar on Oil Spill Wildlife Response Planning. The 2-day workshop was held at the Patuxent Wildlife Research Center at Laurel, Maryland. Some 70 State and Federal government personnel in charge of oil spill response plans involving wildlife participated. The program addressed itself to fish and wildlife considerations and the role of regional response teams under the National Oil and Hazardous Substances Pollution Contingency Plan. The actions of State wildlife departments, U.S. Fish and Wildlife Service, Environmental Protection Agency, U.S. Coast Guard, and the oil industry in handling spills involving wildlife were examined. The latest oil spill cleanup technology was reviewed, and the workshop ended with demonstrations of the cleaning of oiled waterfowl. Similar seminars were planned for the Gulf of Mexico and the West Coast.

It was obvious from this seminar that the most comprehensive wildlife oil spill contingency plan had been developed by the State of California. Copies of this plan (Oil and Hazardous Materials Contingency Plan, California Department of Fish and Game, July 1974) were later distributed to all coastal States as a prototype or model plan by API.

The U.S. Fish and Wildlife Service has been conducting experiments on various bird-cleaning agents and techniques at its Migratory Bird and Habitat Research Laboratory near Laurel, Maryland. The Fish and Wildlife Service is also working with the API in developing information on migratory patterns and winter waterfowl concentration areas on the East Coast as they relate to petroleum transport traffic and oil terminals.

In Canada, the Petroleum Association for Conservation of the Canadian Environment (PACCE) employed the services of a consulting firm to make a comprehensive review of dispersal and rehabilitation of waterfowl associated with oil spills. The resulting PACCE report (LGL Ltd. 1974) codified what was known about the problem, identified research needs, and developed effective wildlife oil-spill contingency plans for critical areas on Canada's east and west coasts, the Great Lakes, and the Arctic.

The Florida Game and Fresh Water Fish Commission has initiated a program for the rehabilitation and treatment of oiled birds. It is being organized by veterinarian Harold F. Albers of St. Petersburg. He is working in cooperation with the Florida Associated Marine Institutes, the Shell Oil Company, Clean Gulf Associates, and the API.

The Standard Oil Company of California provided a grant to James Naviaux of Pleasant Hill, California, to develop bird-cleaning technology, including the testing of various cleaners. Dr. Naviaux had treated birds from the 1971 San Francisco spill. A publication on the after-care of oil-covered birds (Naviaux 1972) resulted from the collaboration with Alan Pittman, research chemist of the U.S. Department of Agriculture's Western Research Laboratory.

In 1971, the API in cooperation with the National Wildlife Federation (NWF) initiated an NWF/API Fellowship program. One of the first grants under this program was to Charles W. Kirkpatrick, Professor of Wildlife Management at Purdue University. He and assistants studied for 4 years the nesting ecology and productivity of the emperor goose (Philacte canagica) in the Igiak Bay area of the Yukon Delta in Alaska (Eisenhauer and Kirkpatrick 1977).

An extensive program of marine bird research was initiated on the North Slope of Alaska by the Atlantic Richfield Company in 1969. It has been continued ever since and includes the acquisition of extensive base-line data on all waterfowl, including June surveys of breeding pair counts and August surveys for brood counts. The results of these surveys for 1969-73 are presented by Gavin (1975).

Base-line data on marine birds of the Gulf of Alaska are currently being collected and compiled through grants to various universities and institutions by the American petroleum industry. These data will constitute elements of a report on the environmental status of the Gulf of Alaska. Such information is essential prior to development of the Gulf's offshore petroleum resources.

Marine Mammals

Most sea mammals are relatively resistant to oil slicks and tend to avoid contaminated waters. As a result, little research has been conducted on cleaning and treatment techniques except for experiments on live beavers and on the carcasses and pelts of sea otters and beavers.

No sea otter or seal has ever been oiled and subsequently cleaned in an oil spill situation. It is possible, however, that a spill could have significant adverse effects on sea otters and fur seals, especially at a rookery during the pupping season. These animals depend on an air blanket trapped in their dense underfur for warmth and buoyancy. Any form of pollutant, especially oil, could penetrate the outer guard hairs and underfur and allow water to reach the skin, with disastrous effects.

Seals and otters are powerful animals, and the larger males and females can be quite aggressive and dangerous. Only professional wildlife specialists and consulting veterinarians should be permitted to handle and treat them. A guide to cleaning and care of oiled sea otters can be found in the California Oil and Hazardous Materials Contingency Plan.

Conclusions

This status report has revealed that substantial efforts and progress have been made in oiled-wildlife research. New techniques being developed are leading to higher survival rates. Preventive measures are being devised to keep birds from entering a spill area. Wild life contingency plans are being developed and materials to handle future emergencies are being stockpiled. Basic research is being continued on the difficult problems inherent in achieving high survival levels and a rapid return to the wild, at a reasonable cost.

Much more must be done, but these pioneering efforts both within and outside of industry reflect a difficult problem yielding to the time and attention of dedicated men and women.

References

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