(from "Research on Whales", ICR, 1995)

Dr. Seiji Ohsumi

Animals can be broadly classified into domesticated, or tamed, and undomesticated, or wild. Wild animals, unlike their domesticated counterparts, live independently and freely in a natural environment without human-imposed supervision or restrictions; whales are generally regarded as wild animals.

The biological study of wild animals may be conducted using either lethal or nonlethal techniques. Ever since modern whaling activities became widespread in the 1920s, most biological studies of whales have been conducted through lethal techniques in conjunction with the whaling industry. In recent years, however, whaling operations have been either restricted or banned entirely. At the same time, advances in behavior studies and biotechnology have led nonwhaling nations to advocate the possibility and necessity of introducing nonlethal study techniques. As such nonlethal techniques have been developed and put into use, antiwhaling forces have condemned and attacked lethal study techniques, which they regard as conferring tacit acceptance and approval of whaling, and have recommended the exclusive use of nonlethal techniques. The fact is, however, that research cannot be conducted comprehensively using nonlethal techniques and that a number of research topics cannot be explored without resort to lethal study techniques.

This paper reviews the historical background of lethal and nonlethal biological studies on whale populations in the context of the unique biological characteristics of these creatures. It explores the advantages and disadvantages of different techniques. It also discusses how whale population studies should be conducted in future.

Biological Characteristics of Whales

Ohsumi (1992) lists five biological characteristics of whales that relate to lethal and nonlethal studies. The first is that whales are mammals which spend their entire lives in water. Most whales, even killer whales, which are kept in captivity at aquariums can learn to leap out of the water onto the side of a pool when they are properly trained. In the wild, however, whales never attempt to move about on land except in pursuit of prey that is either on shore or has fled onto land. Killer whales, for example, will come onto shore to attack South American sea lions that themselves are on land close to the water. Bottlenose dolphins will catch fish which they have chased onto the beach. Some varieties of whales, such as pilot whales, will beach themselves en masse, or may sometimes die and be inadvertently washed up on shore. These are all exceptional cases, and can in no way be considered normal behavior. The fact that whales are aquatic makes it more difficult to employ nonlethal techniques for observing behavior that are used with terrestrial animals. Whales expose themselves only partly out of water, for example, and it is difficult to identify individuals from their appearance. Whale fecal matter is excreted into the water in liquid form, which makes collection difficult. This in turn makes it difficult to study feeding habits nonlethally. Because of their aquatic existence, whales leave no footprints, which of course makes it impossible to conduct the types of footprint studies used for terrestrial animals.

The fact that whales are completely aquatic means that ships or aircraft are required to conduct active systematic research. Some species, such as gray whales, naturally live close to land and individuals occasionally approach shore. In these cases, nonlethal study can be conducted from land, but, again, these cases are exceptional. Researchers can often study terrestrial animals alone and on foot, and without any great expense. The study of whales, however, requires research ships or aircraft that are very expensive to operate and require the cooperation of extensive crews and other staff.

The second ecological characteristic of whales is their enormous biological domain. Most varieties of whales migrate over great distances and thus have the largest biological domain of any mammal. Combined to the first characteristic discussed above and the third to be described below, this fact further increases the cost involved in conducting whale research, while making the entire research undertaking more difficult. This is true regardless of whether lethal or nonlethal techniques are involved.

The third ecological characteristic of whales is their relative speed, agility, and deep-diving behavior. Sperm whales can dive to a depth of 3,000 meters, while killer whales swim at a speed of 35 knots or more. Research ships must be fast and at least as maneuverable as whaling ships, regardless of whether lethal or nonlethal studies are being carried out. This, combined with the second characteristic, above, has given impetus to the development of telemetry techniques for use in nonlethal study.

The fourth ecological characteristic is their need, as mammals, to breathe air directly, which is why they rise to the surface as needed. This characteristic is advantageous in both lethal and nonlethal whale study because this enables them to be captured or observed.

The fifth characteristic is the length of their lives at sexual maturity, long reproductive cycles, and long life spans. Female sperm whales, for example, reach sexual maturity at age nine and bulls at age 25. Their sexual cycle is four or five years and their maximum life span 70 years. This means that very long-term research projects are necessary in nonlethal study. Lethal methods produce results comparatively quickly, which is advantageous when urgent research is needed on a given animal.

Whales generally are large, with blue whales, for example, having a measured record body length of 34 m and body weight of 190 tons. This means that lethal study cannot be conducted by researchers on their own, and must be carried out in cooperation with whalers.

The morphological, ecological, and physiological characteristics described here must be understood and the research objectives and social urgency taken into account when considering whether to use lethal or nonlethal techniques. Depending on the assessment of these factors, research can be designed and conducted efficiently using either technique or a combination of the two.

History of Lethal and Nonlethal Methods in Ecological Whale Studies

Up to 1920, scientific knowledge about whales was gleaned primarily from long-time museum samples, from rare stranding deaths, and from serendipitous shipboard behavioral observations by sailors. The whaling industry of centuries ago benefited little from the development of science and contributed correspondingly little to the accumulation of scientific knowledge.

The first modern research studies on whale ecology were conducted in the 1920s, when modern Antarctic whaling made dramatic advances, by researchers from Great Britain and Norway, the leading whaling nations of the time. Great Britain established the Discovery Committee in 1924 to undertake systematic studies on the oceanography of the Antarctic (Mackintosh, 1950). Much of this research consisted of whale population investigations and studies. Norway, the world's leading whaling nation, also formed a powerful government/industry/university alliance to initiate whale population studies (Ruud, 1953).

All of these studies were conducted in conjunction with the whaling industry and focused on whaling statistics involving attempted and actual catches, together with biological studies of the individual whales caught. These were the prototypical lethal studies that continued to serve as the foundation for whale resource studies thereafter. Norway increasingly emphasized the compiling of whaling statistics, while Great Britain placed greater stress on the biological study of captured whales.

During this period, Great Britain and Norway initiated joint research into the intrabody tagging method, a lethal technique that utilized whale mark. This method was implemented by Great Britain in 1933 and in whale marking research conducted widely in the Antarctic after then. As it happens, the Japanese whaling ship captain and gunner Taisuke Amano had already run successful tests on intrabody tagging in waters near Japan in 1910. Since Mr. Amano conducted this research on his own, however, this technique was not systematically developed in Japan until after the Second World War.

The accumulation of whaling statistics began with the establishment of the Committee for Whaling Statistics in Norway in 1929. The statistics collected by this Committee provided a foundation for whale population studies. In addition, analytical results from British biological studies on captured whales served as the basis for whale size limits and other whaling management provisions incorporated into a series of international whaling treaties and conventions during the 1930s.

In the 1930s, the first studies were undertaken in the oceans - the whales' natural environment - but other studies of whale ecology had already incorporated the nonlethal technique of visual study. The English ocean research vessel Discovery II spent six years in the Antarctic engaged in sightings study of whales, representing the first ever such systematic study. Whale sightings were conducted both in conjunction with and separately from whaling operations, and provided valuable information about whale distributions, seasonal movements, and abundance over a large domain and a long period of time.

The 1930s also witnessed the first attempts, in the United States, to raise whales in captivity in large aquariums; these efforts laid the foundation for the behavioral observation of whales. The observations conducted in aquariums were themselves nonlethal but, by capturing whales and putting them in a closed environment, the aquariums restricted their natural behavior. Capturing a living creature may be nonlethal but there are differences of opinion regarding its effect on the animal's well-being. Some very recent research projects have taken to capturing an animal, conducting all required measurements and collecting data, and then releasing the animal back into the wild. This technique limits the animal's freedom only temporarily, but it is not practical for larger whales.

During the 1940s, the Second World War dealt a serious blow to whaling worldwide and pushed whale population studies into the background. During the War, however, some physiological and ecological whale studies were undertaken, especially on topics such as soundings of whales having possible military implications. These studies used auditory experiments and other nonlethal study.

The world whaling industry began recovering immediately after the end of the Second World War and, in 1946, a new International Convention for Regulation of Whaling was signed which is still in force today. The International Whaling Commission (IWC) began operations in 1948 under the auspices of the Convention. Leading whaling nations recommended whale population studies and, in 1947, the Whales Research Institute was established in Japan. The Institute initiated a number of whale population studies of its own (Okuda, 1954).

In the 1950s, whaling operations surpassed prewar levels and it soon became apparent that whale resources were dwindling. The realization of the need to strengthen whale population studies as a way of facilitating scientific resource management grew increasingly widespread. Studies of methods to determine whale ages became extremely important for management. The methods involved body parts and necessitated lethal means to obtain the required specimens. (Ohsumi, 1967). Of all the physical indicators studied during this period, the one judged to be the best and most accurate indicator of age was the ear plugs in baleen whales and the teeth for toothed whales. Except for the teeth of certain species of whales, such indicators can only be studied using lethal methods.

Whale age determination methods had been formulated by the 1960s and, together with accumulated biological study results, these methods contributed to population analysis works undertaken by the IWC on several main whale resources. The results of these works led the IWC to tighten whale resource management. The ensuing reduction in whale catch quotas made it uneconomical for European and American nations to continue whaling, since they were catching whales only for whale oil and, one by one, they withdrew from whaling operations. Around this time, environmental protection movements were growing in these countries and antiwhaling movements became a very active outgrowth of environmentalism. Halting progress began to be made in developing nonlethal methods of whale study not relying on the whaling industry.

During this period, it had become evident that Californian gray whale populations were recovering. Whale watching grew popular along the Californian coast, which provided impetus to the development of field whale observation methods. A number of studies were undertaken in Japan in the mid-1960s in an effort to systematize whale sightings (Ohsumi and Yamamura, 1982), but the series of research reports from Japan that made use of nonlethal whale sightings was ignored by the Scientific Committee (SC) of the IWC at that time.

In the 1970s, the environmental protection movement became global. The United Nations sponsored the Conference on the Human Environment in 1972. After a 10-year moratorium on whaling was adopted at the Conference, antiwhaling forces increasingly sent their own influential scientists to the SC to launch a fierce assault on the use of lethal whale study and the use of analytical data obtained from such study which, they argued, lent tacit approval to the continuation of whaling. The SC then became embroiled in a fierce and lengthy ideological conflict between scientists sent to smear the whaling industry and those who insisted on the necessity of lethal study. In an effort in 1978 to resolve the conflict between the two camps, the IWC initiated an international 10-year whale study plan, commonly known as the IDCR, a joint international program to conduct whale sighting surveys in the Antarctic. Antiwhaling scientists finally accepted the program because it involved nonlethal techniques, which had previously been ignored when conducted by Japan. From this point on, sighting survey techniques developed rapidly on both operational and theoretical levels.

The first attempts were made in the 1960s to conduct field observation of right whales through individual identification - a typical nonlethal whale study. The practice spread in the 1970s to encompass numerous varieties of both larger and smaller cetaceans (Anon., 1990). Radio transmitting equipment was first attached to whales in the wild in the 1960s (Schevill and Watkins, 1966), and, from the 1970s on, a number of technological advances in whale biotelemetry was seen.

The strategy of antiwhaling forces to increase the number of IWC member nations succeeded. In 1982, the IWC imposed a moratorium on commercial whaling, banning the killing of whales with the exception of certain cetacean species of whales caught by aboriginal peoples as approved by the IWC as well and certain cetacean species not subject to IWC control. Believing, however, that the whaling moratorium would improve progress in whale population studies, Japan, Iceland, Norway, and South Korea resumed research by capture of whales for scientific purposes in 1987 under the application of Article 8 of the International Whaling Convention. The antiwhaling forces within the IWC, however, adopted a variety of limitations on research authorized under Article 8, conditions that made these studies difficult to conduct. Rapid advances continued to be made in biopsy, another nonlethal form of study, accompanied by the development of DNA techniques in the 1980s. Nevertheless, these techniques were not yet fully mature.

As the Cold War came to an end in the early 1990s, a number of initiatives were under way to apply military techniques to peaceful purposes. One of these involved the application of acoustic devices developed for submarines to studies of whale ecology (Clark, 1994). This was also nonlethal.

Thus, lethal and nonlethal study techniques have gradually developed in keeping with the changing tenor of the times and with advances in technology. Countries dominated by antiwhaling forces, however, have implemented restrictions on use of lethal techniques of study despite their value in certain types of research, and researchers are forced to rely exclusively on nonlethal study. At the same time, whaling nations can continue to use lethal study techniques, and whale population studies are advancing as a result.

Lethal and Nonlethal Whale Population Study Techniques

Whale ecology is, and has been, conducted in a number of forms, including population studies in conjunction with whaling operations: special research under the auspices of Article 8 of the Convention; studies of whales caught by accident during other fishing operations; marine pollution studies; and purely scientific studies, among others. This chapter discusses the specifics of both lethal and nonlethal techniques used in whale population studies.

1. Lethal Research

1.1 Whaling Statistics

Whaling statistics are obtained in the course of whaling operations, and consist of fishing effort and catch statistics.

1.1.1 Fishing effort statistics

When a whaling vessel reaches a whaling ground, it first attempts to sight a pod of whales. Once a pod is sighted, the vessel proceeds rapidly to the location, choose a target, and starts pursuit. Once the vessel has reached harpooning range, the harpoon is fired and the whale is captured. Contents of fishing effort statistics include the number of whaling fleets, number of whaling vessels, number of days of operation, operation time, and time spent searching.

1.1.2 catch statistics

Major parameters include the number of whales caught geographically, monthly, by species, by sex, and production by weight.

1.1.3 Use of catch statistics

Catch statistics represent a critical basic resource for the whaling industry, but the combination of fishing effort and catch statistics is used as an index of population density. In combination with data from biological research, these statistics make it possible to perform a variety of population analyses.

1.2 Biological Investigation of Captured Individuals

Biological investigations are conducted on captured individual whales. The content of such an investigation consists of recording the date and location of capture; identification of the species; identifying the sex; measuring the body length, morphological characteristics, body proportions, total weight, weight of body parts; collecting age indicators; assessing the sexual maturity and condition; counting the number, sex, and body length of fetuses; studying and collecting the stomach contents; collecting tissue samples from each body part; recording and collecting internal and external parasites and measurements of the bone structure; and collecting bone samples. Except in very rare cases, these studies can be conducted only on specimens collected lethally.

1.3 Tagging Studies

Tagging methods are implemented differently for different animals. In the case of whales, these involve firing a whale mark into the whale's body and recovering the tag when the whale is captured. Combined with the biological studies and specimen collections described above, tagging records - including the date, location, species, estimated body length, school composition, verdicts, etc. - provide information about the distribution, movement, migration, growth, age, mortality rate, and population size of whales. This excellent ecological research methodology has yielded substantial results. Because it involves whaling, however, it is under assault by antiwhaling scientists. Since the 1980s, it has become largely impossible to conduct such studies, except for occasional recoveries from research takes.

2. Nonlethal Research

Nonlethal techniques have been used in ecological whale studies since earliest times, as the following sections on nonlethal research related to whale population studies explain.

2.1 Whale Sightings

Whales are observed visually when they surface to breathe in order to identify species; study distribution, density, and population size; identify a school structure; and study submerging and other forms of behavior.

2.2 Environmental Research

Oceanographic research is conducted to obtain information about the physical, chemical, and biological environments of whales.

2.3 Acoustic Survey

Whale calls are studied to obtain information about whale distribution density, population size, and movement.

2.4 Biopsy Sampling

Skin samples obtained from whales using an arrow-shaped instrument are subjected to DNA, chromosome, and hormone analysis.

2.5 Biotelemetry Surveys

Radio transmitting equipment and monitoring devices are attached to whales to measure and record information about their movement, submerging behavior, pulse, and other physiological information, along with information about water temperature and other environmental factors.

2.6 Individual Recognition

Individual whales are identified by distinguishing physical characteristics, yielding information about population size, movement, growth, fertility, mortality rate, and school composition.

2.7 Live Capture Investigation

Whales are either immobilized using a tranquilizer or caught in netting that restrains their movement but does not physically injure them. Measurements are taken of the body length, weight, and temperature; the sex is determined; blood samples and skin biopsies are taken; and ultrasound equipment is used to view the interior of the whale's body. After these and other types of information are collected, a pinger or other device is attached to the whale and it is released.

2.8 Studies in Captivity

Live whales are caught and raised in captivity, where their behavior is observed to yield basic research data. This method is not yet advanced enough, however, to be used with larger whales, and therefore cannot be applied to the majority of species targeted for whaling.

Necessity of Lethal Techniques in the Study of Whale Populations

Both lethal and nonlethal study have unique strengths and weakness. Table 1 compares the two techniques as they relate to considerations required when conducting research, and Table 2 lists the advantages and disadvantages of each technique in achieving specific research objectives.

Determining the age of a wild animal is indispensable to ecological research. Individual identification forms the basis of age research using nonlethal study. Individual whales differ considerably in visible signs of body size, color, and scarring of the skin, and none provides a clear-cut indicator of a whale's age. It is thus not possible to determine a whale's age by observation from the outside alone. Whales are very long-lived, with some whale species surviving over a century (Ohsumi, 1979). To determine the maximum age of a whale, for instance, using nonlethal techniques would require that a research project follow a single identified individual as long as 100 years. Such knowledge can be obtained very quickly, however, using lethal methods, because age determination techniques are well-established for almost all species of whales. It is easy to determine the maximum age for a particular species if an appropriate number of individuals are captured and their age indicators are collected and analyzed to determine their individual ages. It is possible to obtain some age indicators using nonlethal techniques only for smaller whales easy to capture live and having many teeth in their mouths. Baleen whales are extremely large and difficult to capture live, and their ear plugs can be obtained only by dissecting the head, i.e., their age can only be determined in ways lethal to the subject under study.

Important biological parameters that can only be assessed on age include age at sexual maturity, age at recruitment, recruitment rates, and natural mortality rates. One issue that the IWC has recently been closely involved with is the effect of marine pollution and other changes in the ocean environment on whale resources. Age information is central to any effort to study the effect of marine pollution on whale resources, because pollutants accumulate in whale's bodies as they age and, without age information, pollution studies will not progress.

Pollutants accumulate in the liver, kidneys, and other internal organs, meaning samples of those organs must be obtained to study pollutant levels - again, a requirement lethal to the subject. Pollutants variously affect tissues in which they accumulate. Using nonlethal skin biopsy sampling alone will not yield adequate research data. DNA analysis has been widely used to identify stock structures. The liver and muscle tissue so valuable for DNA analysis, however, cannot be obtained through nonlethal biopsy sampling at all.

Japan is currently conducting whale capture studies in the Antarctic and in the North Pacific under the auspices of Article 8 of the International Whaling Convention. The objectives of the studies being conducted in the Antarctic are to identify biological parameters required for rational population management of minke whales and to determine the roles played by whales in the Antarctic ecosystem. These objectives can only be achieved by lethal study. Research is designed to incorporate lethal and nonlethal techniques combined and to obtain as few samples as possible while still meting research goals. Systematic studies involving nonlethal whale sightings are planned over a vast research area together with random lethal captures of whales, from which precise measurements are taken and samples obtained covering a large number of research topics to use these samples most effectively. These studies represent part of a 16-year long-term research project that has already yielded a number of new insights into identification and distribution of stocks, and segregation by age and sex. One of the features of lethal study is that post-study by-products are used advantageously in accordance with Article 8 of the Convention, and proceeds from the scale of these by-products help offset some of the enormous costs entailed by this research. Such measures would be impossible if only nonlethal methods of study were employed.

Japan has contributed significantly to progress in IWC/IDCR research and, as this research has progressed, it has become evident that the population of beaked whales, including Southern bottlenose whales, is in the hundreds of thousands, with these whales playing an extremely important role in the Antarctic ecosystem. Because these whales were not commercially exploited, our knowledge of their biology is still extremely poor. This alone shows the important contribution which lethal study, in conjunction with whaling operations, has made to our understanding of whale biology and how meager our knowledge is of species not commercially utilized. These whales are related to toothed whales and are higher in the food order than minke whales, for example, making them a good indicator of pollution in the Antarctic. Further lethal studies need to be initiated with these whales as soon as possible to raise our level of basic biological knowledge about them and to use these whales as an index of environmental change in the Antarctic.

The purpose of research takes of minke whales in the North Pacific, begun in 1994, is to elucidate the structure of stocks and substocks in this species of whale. This is an emergency study undertaken to establish the validity of the substock scenario envisioned by the IWC/SC in relation to the establishment of managed sea zones where the revised management procedure (RMP) will be applied to North Pacific minke whales. Lethal study is required to investigate substocks, but these studies fall within the definition of authorized research under the provisions of Article 8 of the Convention. DNA, isozyme, and other genetic techniques must be used to isolate stocks, meaning muscle and liver tissue must be sampled, which can only be done lethally. Since it is already known that the breeding season for North Pacific minke whales differs by stock, it is important to study the growth of fetuses. This can only be done by capturing pregnant females and measuring the size of fetuses. Stock groupings may also be identified based on feeding habits, comparisons of accumulated pollutants, and parasitic organisms. The examination of the body and measurement of certain characteristics is also very important. All of these factors can only be determined from dead animals. Nonlethal radio tagging technology to determine movements and stock structure has not yet reached the operational stage and, while some biopsy studies have been attempted, the technology is not yet sufficiently developed. The urgency of this research to determine stocks makes the use of lethal study indispensable.

Nonlethal study is used exclusively when the whale species is rare or in danger of extinction. For species with healthy and relatively large populations, however, lethal study can yield research results very quickly - a factor that should be taken advantage of, together with the systematic combination of lethal and nonlethal techniques to advance biological research on whales as quickly as possible.

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