ACKNOWLEDGMENTS

Figure 168.—A harbor porpoise harpooned in Passamaquoddy Bay, New Brunswick. Harbor porpoises have from 23 to 28 small, spade-shaped teeth in each upper jaw and from 22 to 26 in each lower jaw. Note the rounded head, the absence of a beak, and the triangular dorsal fin. (Photo by D. E. Gaskin.)

Obviously this guide could not have been produced without the cooperation of many people. Of over 450 individuals and scientific organizations contacted in 14 countries, 255 responded to our letters and well over 100 provided photographs for review and selection. We were particularly pleased that for the majority of the species found in the western North Atlantic our most difficult problem was narrowing the choices and ultimately selecting illustrations from the many good materials made available to us. Although there are far too many contributors to mention all by name, their prompt and enthusiastic responses to requests for help are gratefully acknowledged, whether or not their materials were used.

Although photo credits follow each figure, we would particularly like to cite the generosity of Marineland of Florida, Hideo Omura of the Japanese Whales Research Institute, J.G. Mead of the U.S. National Museum, K.C. Balcomb of Moclips Cetological Society, Seiji Ohsumi of the Far Seas Fisheries Research Laboratory, Jack Lentfer of the Alaskan Department of Fish and Game, the U.S. Naval Undersea Center (NUC), The University of Rhode Island, and William F. Perrin of the National Marine Fisheries Service (NMFS). Photographs by Taruski, McCann, Hain, Wheeler, and Rigley are in Winn's files. All others are in the files of Leatherwood and Caldwell. The illustrations for Figures B1 and D1 were prepared by George Galich of NUC. All other illustrations were prepared by Lois Winn.

The extensive and often tedious job of preparing black and white photographs of suitable format from the vast array of black and white and color negatives and prints and from color transparencies was accomplished at the NUC Photographic Laboratory by the able team of Domingo Sanchez, Ray Krenik, Jeanne Lucas, and Alan McPhee.

George E. Lingle and John C. Moore assisted with gathering and reviewing the literature and with cataloging and screening photo materials.

The various drafts of the manuscript were typed by Linda Thomson, Margaret Alvarez, and Sandra Nolan. Sandra Peterson assisted with proofreading the later drafts.

In preparing this guide we drew freely from the literature on cetaceans of this region and supplemented it with our own observations and with unpublished notes provided by our colleagues. A partial list of materials used, each a good source of reference material on cetaceans in general or on cetaceans of the western North Atlantic in particular, is provided in the following section, "Selected Bibliography."

All of the following colleagues read all or part of the manuscript and made useful suggestions for its improvement: K.C. Balcomb, W.C. Cummings, J.G. Mead, Hideo Omura, W.F. Perrin, F.K. Rodgers, Allen N. Saltzman, D.E. Sergeant, W.A. Watkins, A.A. Wolman, and F.G. Wood.

All of the information and photographs contributed by Lois Winn were obtained under grants from the Office of Naval Research. Funds and assistance for the preparation of intermediated drafts and logistics support for all stages of preparation of this guide were provided by Biological Systems, Inc., St. Augustine, Fla.

In addition to securing funds for the preparation and publication of this guide, Paul Sund, Platforms of Opportunity Program, NMFS, Tiburon, Calif., provided continuing help and criticism.

To these and to all who use this guide to further help knowledge about the cetaceans of the western North Atlantic, we are grateful.

ANDERSEN, H. T. (editor).

1969. The biology of marine mammals. Academic Press, N.Y., 511 p.

BURT, W. H.

1952. A field guide to the mammals. Houghton Mifflin Co., Boston, 200 p.

CALDWELL, D. K., and M. C. CALDWELL.

1973. Marine mammals of the eastern Gulf of Mexico.InJ. I. Jones, R. E. Ring, M. O. Rinkel, and R. E. Smith (editors), A summary of knowledge of the eastern Gulf of Mexico, p. III-I-1—III-I-23. State Univ. Syst. Fla. Inst. Oceanogr., St. Petersburg, Fla.

CALDWELL, D. K., and F. B. GOLLEY.

1965. Marine mammals from the coast of Georgia to Cape Hatteras. J. Elisha Mitchell Sci. Soc. 81:24-32.

CALDWELL, D. K., H. NEUHAUSER, M. C. CALDWELL, and H. W. COOLIDGE.

1971. Recent records of marine mammals from the coasts of Georgia and South Carolina. Cetology 5:1-12.

FRASER, F. C.

1937. Whales and dolphins.InJ. R. Norman and F. C. Fraser, Giant fishes, whales and dolphins, p. 201-349. Putnam and Sons, Lond. [There are several editions of this work, all with the same information.]1966. Guide for the identification and reporting of stranded whales, dolphins and porpoises on the British coasts. Br. Mus. Nat. Hist., Lond., 34 p.

1966. Guide for the identification and reporting of stranded whales, dolphins and porpoises on the British coasts. Br. Mus. Nat. Hist., Lond., 34 p.

GOLLEY, F. B.

1966. South Carolina mammals. The Charleston Museum, Charleston, S.C., xiv + 181 p.

GUNTER, G.

1954. Mammals of the Gulf of Mexico.InP. S. Galtsoff (coordinator), Gulf of Mexico, its origin, waters, and marine life, p. 543-567. U.S. Fish Wildl. Serv., Fish. Bull. Vol. 55.

HALL, E. R., and K. R. KELSON.

1959. Order cetacea—cetaceans.InThe mammals of North America, 2:806-840. Ronald Press, N.Y.

HERSHKOVITZ, P.

1966. Catalog of living whales. Bull. U.S. Natl. Mus. 246, 259 p.

KELLOGG, R.

1940. Whales, giants of the sea. Natl. Geogr. Mag. 77:35-90.

LAYNE, J. N.

1965. Observations on marine mammals in Florida waters. Bull. Fla. State Mus., Biol. Sci. 9:131-181.

LEATHERWOOD, S., W. E. EVANS, and D. W. RICE.

1972. The whales, dolphins, and porpoises of the eastern north Pacific. A guide to their identification in the water. Nav. Underseas Cent., Tech. Publ. 282, 175 p.

LOWERY, G. H., JR.

1974. The mammals of Louisiana and its adjacent waters. Louisiana State Univ. Press, Baton Rouge, 565 p.

MITCHELL, E. D.

1973. The status of the world's whales. Nat. Can. 2(4):9-25.

MOORE, J. C.

1953. Distribution of marine mammals to Florida waters. Am. Midl. Nat. 49:117-158.

NORRIS, K. S. (editor).

1966. Whales, dolphins, and porpoises. Univ. California Press, Berkeley, 789 p.

PALMER, R. S.

1954. The mammal guide. Doubleday and Co., N.Y., 384 p.

RICE, D. W.

1967. Cetaceans.InS. Anderson and J. K. Jones (editors), Recent mammals of the world; a synopsis of families, p. 291-324. The Ronald Press, N.Y.

RICE, D. W., and V. B. SCHEFFER.

1968. A list of the marine mammals of the world. U.S. Fish Wildl. Serv., Spec. Sci. Rep. Fish. 579, 16 p.

RIDGEWAY, S. H. (editor).

1972. Mammals of the sea; biology and medicine. Charles C. Thomas, Springfield, Ill., xiii + 812 p.

SCHEVILL, W. E.

1974. The whale problem. Harvard Univ. Press, Cambridge, Mass., 297 p.

SERGEANT, D. E., and H. D. FISHER.

1957. The smaller Cetacea of eastern Canadian waters. J. Fish. Res. Board Can. 14:83-115.

SERGEANT, D. E., A. W. MANSFIELD, and B. BECK.

1970. Inshore records of Cetacea of eastern Canada, 1949-68. J. Fish. Res. Board Can. 27:1903-1915.

SLIJPER, E. J.

1962. Whales. Hutchinson and Co., Ltd., Lond., 475 p. [There is also an American edition.]

TOMILIN, A. G.

1967. Cetacea. Mammals of the U.S.S.R. and adjacent countries. Isr. Program Sci. Transl., Jerusalem, Vol. IX, 717 p. [A compilation of worldwide data, originally published in Russian.]

TOWNSEND, C. H.

1935. The distribution of certain whales as shown by logbook records of American whaleships. Zoologica (N.Y.) 19:1-50.

TRUE, F. W.

1889. Contributions to the natural history of the cetaceans, a review of the family Delphinidae. Bull. U.S. Natl. Mus. 36:1-192.

WALKER, E. P.

1964. Mammals of the world. The Johns Hopkins Press, Baltimore, p. 1083-1145. [Cetaceans. There is also a second, revised edition of this work, and a third, revised edition is planned.]

Field studies of cetaceans are very difficult. First, it is extremely hard to be positive that an individual or a group of animals is the same from one encounter to the next. This means that it is nearly impossible to determine, for example, whether herds of animals are resident in an area or only seasonal visitors. Without information of this kind, determinations vital to population management, such as sizes of populations and natural ranges, are impossible to make.

Secondly, as we frequently point out in this guide, individual cetaceans are usually visible to a surface observer only during the brief moments when they break the air-water interface to breathe. The majority of their vital activities (e.g., feeding, reproduction, communication, establishing and maintaining position within the herd, and defending against natural enemies) take place primarily below the surface, well out of view to a surface observer.

In recent years, in an attempt to overcome some of these problems, scientists have been placing markers on various species of cetaceans and monitoring their movements. The following brief summary of major methods of tagging cetaceans is provided to acquaint the reader with markers he may expect to see in the western North Atlantic.

Since their development in the mid-1920's, numerous Discovery marks (small stainless steel projectiles with identifying information stamped on them) have been shot into commercially valuable species by means of a shotgun. The recovery of these marks from whales subsequently killed in the whaling industry has provided valuable information on the movement patterns and on basic aspects of the growth and development of harvested species of whales. Discovery marks are limited, however, because they are not visible in a living animal. Reduction in whaling activities will bring about a significant reduction in their use.

More recent tagging developments relate to marks which will be visible on a free-swimming animal. Large whales, for instance, may be tagged with color-coded streamers, such as that shown inAppendix Figure A2. The tags, which are modified versions of the spaghetti tags first constructed for use on fishes, consist of a small stainless steel head for attachment to the blubber and a colorful streamer (sometimes stamped with information on agencies to which tags should be returned) which is visible above the surface of the animal. These tags may be applied by using either a pole applicator or a crossbow and crossbow bolts. Both applicators are equipped with a stop to limit the depth of penetration into the animal's blubber. Extensive experimentation indicates that the tags do not harm the animals and that their application is not traumatic. With the continued reduction in whaling activity, it is hoped that the use of such markers in the study of movements of big whales will be increased.

Because they often ride the bow wave of a moving vessel, thereby making themselves accessible for tagging and capture, small porpoises and dolphins have been tagged with a greater variety of marks than large whales. In recent years, at least three kinds of static tags, including spaghetti streamers, have been placed on small and medium-sized cetaceans.

Spaghetti tags, placed in the animal's blubber near the base of the dorsal fin as it rides the bow wave, stream to conform to the contour of the animal's body as it swims (App. Fig. A3). It is not possible to identify the numbers on the spaghetti tag of a moving animal, although color codes may be used to indicate different species, populations, or tagging areas.

Button tags and freeze brands are placed on captured animals prior to their release. The button tags (App. Figs.A4,A5) are placed in the dorsal fin and should be visible as the animal surfaces to breathe or as it rides the bow wave. At close range, the number, letter, or design may also be visible. Freeze brands (App. Fig. A6) are placed on the back or dorsal fin with a supercooled branding iron, apparently without pain or discomfort to the animal, and provide a permanent mark which leaves the tagged animal free of encumbrances. The use of freeze brands shows promise and should come into more extensive use.

Other static tagging techniques currently under investigation include the use of laser beams to apply smallbrands and the use of gas branding devices. Neither technique, however, has yet reached the field biologist.

The success of any tagging program using static tags depends on the resighting of tagged animals and the recovery of tags. For that reason, we appeal to readers to be on the lookout for tagged animals and to report sightings to one of the authors.

Appendix Figure A1.—Some of the basic kinds of tags used to mark porpoises, dolphins, and small whales. A, B, and C are nylon button tags, which are placed in the dorsal fin of animals and may be clearly visible as the animal surfaces to breathe. D is a vinyl spaghetti tag. (Photo by R. Krenic, courtesy of Naval Undersea Center.)

Appendix Figure A2.—A spaghetti tag in the back of a blue whale off San Clemente Island, Calif. (Photo by S. Leatherwood.)

Appendix Figure A3.—A spaghetti tag in the flank of a bottlenosed dolphin off Loreto, Baja California, Mexico. This particular tag was placed unusually low. The streamer and spaghetti tags are usually placed high on the back, just in front of the dorsal fin, and are clearly visible as the animal surfaces to breathe. (Photo by W. E. Evans.)

Appendix Figure A4.—A button tag placed on the dorsal fin of a newly captured saddleback dolphin off Catalina Island, Calif. (Photo by W. E. Evans.)

Appendix Figure A5.—This is the way the button tag appears on an animal swimming free in the open sea off Palos Verdes, Calif. (Photo by B. Noble, courtesy of Marineland of the Pacific.)

Appendix Figure A6.—Freeze-branding is an apparently painless method of applying a permanent identifying mark to the body of a porpoise or whale. (Photo of a bottlenosed dolphin off Sarasota, Fla., by A. B. Irvine.)

In recent years, radio transmitter tags have been developed for use on marine mammals. As they continue to become more reliable, these tags are expected to come into more and more widespread use.

Early radio tags (Fig. A7) were simple locator beacons which permitted the animal to be tracked by sending a signal to a tracking vessel or aircraft every time the animal surfaced and the antenna tip was exposed. Even these basic packagesprovide important information on movement, activity patterns, and respiration rates.

Subsequent developments have involved the addition of sensors to monitor the maximum depth of each dive and environmental parameters such as the water temperature at that depth (Fig. A8).

Logical extensions of these developments include the addition of numerous other sensors to permit simultaneous monitoring of multiple aspects of the animal's environment and the transmission of these data first to aircraft and subsequently to satellites for relay to shore-based laboratories.

In addition to permitting scientists to define movement patterns and daily diving patterns of cetaceans, the use of such devices offers an exciting means of determining the environmental parameters that trigger changes in their behavior.

Radio transmitter tags, in a variety of configurations, may be constructed and attached for short-term studies or for long-term monitoring of migrating animals. In either case, depending on their size and methods of attachment, radiotransmitter tags may be visible on a free-swimming animal even at a considerable distance.

Appendix Figure A7.—A saddleback dolphin wearing a radio tag transmitter surfaces to breathe off southern California. (Photo courtesy of W. E. Evans.)

Appendix Figure A8.—A radio transmitter package attached to the dorsal ridge of a California gray whale. This yearling animal, captive for most of the first year of its life, was released into the ocean off San Diego, Calif., in March 1972 and subsequently tracked from shipboard and aircraft for over 30 days. The sensor transmitter package, shown in detail in the inset, was designed to measure the maximum depth of the animal's dive and the water temperature at that depth. (Photo by S. Leatherwood.)

In addition to these man-made and applied tags, variations in natural markings and unusual appearances may be used to identify individuals and herds on repeated encounters. Although many species of cetaceans are characterized by changes in color pattern with age, individuals occasionally differ radically in their coloration from their fellows (App. Figs.A9,A10). In addition, individuals are sometimes seen with unusually shaped dorsal fins or scarring patterns (App. Fig.A11). These unusually marked animals should stand out in repeated encounters and can be a help in identifying a herd from one encounter to another.

Obviously, this list of tags and anomalous markings is not exhaustive. New marks may be developed at any time. The discussion is intended to make the reader aware of the value of information on natural or man-made marks in studies of cetacean natural history. Your cooperation will perhaps help us to unravel some of the mystery surrounding the distribution and movements of porpoises, dolphins, and whales.

Appendix Figure A9.—A piebald saddleback dolphin on the bow of a research vessel off San Clemente Island, Calif. (Photo by B. C. Parks.)

Appendix Figure A10.—A nearly all-white pilot whale seen off Catalina Island, Calif., in April 1971. The observation of this same animal at least once each quarter of the year is evidence that it is resident in that area. (Photo by S. Leatherwood.)

Appendix Figure A11.—A herd of pilot whales off Catalina Island, Calif., including an animal with a partially chopped-off dorsal fin, which has made him recognizable in repeated encounters with pilot whales around the various channel islands. (Photo by G. E. Lingle.)

To increase reliability of identifications, observers should train themselves to ask the following kinds of questions each time cetaceans are encountered:

One characteristic is rarely sufficient by itself, and the greater amount of relevant evidence the observer can obtain, the greater the likelihood he can make a reliable identification. But it is important to remember that even the most experienced cetologists are often unable to make an identification. Therefore, even if you cannot positively identify an animal or even make a good guess as to its identity, do not hesitate to fill out the rest of the sighting record form and submit it to an appropriate office. Listing the characters you observe and filling in as much of the form as possible may enable a cetologist to make an identification based on those characters and his knowledge of the distribution, movements, and behavior of cetaceans. In this regard, a sketch made as soon as possible after the encounter and photographs taken from as many angles as possible will aid in the identification.

Two sample sighting reports are provided to demonstrate a method of recording observations. The first report, "Sighting Information," is completed as an example and is footnoted for explanation. The second report, "Cetacean Data Record." located at the end of the guide, is blank and may be photocopied in bulk for use in the field. Copies of this or similar forms are available from any of the authors or from National Marine Fisheries Service, Tiburon, Calif. Even if no form is available, however, observations should be recorded in rough form, in as much detail as possible.

Reliable intermittent reports of cetaceans are of interest to cetologists. Their locations indicate seasonality of distribution, and their frequencies help indicate relative abundances of the various species. Because scientists are attempting to determine areas in which cetaceans are often, occasionally, seldom, or never found, and are ultimately describing why animals are found in one area and not another, persons who want to go a step further in their participation in observer programs may want to keep and report records of their entire cruise tracks and zones in which vigilance was maintained but no cetaceans were observed. Data obtained in this manner may be used as the foundation of estimates of cetacean populations, estimates which are extremely difficult to obtain by any other method.

To be of maximum use in such calculations, however, records of this kindmustinclude the following minimum information: time and location of beginning and ending of each continuous watch, weather conditions as they affect visibility, sea state, ship's speed, height of the observer(s) above the water, number of persons on watch, and details of each sighting, particularly the estimated distance of the animal(s) from the ship's track.

For a sample of a fictional continuous watch report might look like the following. If sighting forms are available, these observations may be recorded directly onto them. Additional information can be recorded on the opposite side of the forms.

Appendix Figure B1.—A sample cruise track with cetacean sightings. See text for detailed data recording.

RV Melville (34-foot converted fishing boat)U.S. Department of CommerceNMFS

Hydrographic Cruise Miami, Florida to Flamingo, Florida

28-31 January 1973

2 observers (G.E. Lingle and G.M. Mohr)

Eye level of observers:16 feet above water

Average ship speed:8.0 knots during continuous watch

Continuous watch information (refer toFig. B1):

LegDateStart timeEnd timeStart positionEnd positionWeather—Visibility1-22/2812001730U. Miami DockVa. Key25-42N80-02WBeaufort II Visibility3 miles3-42/290800150024-26N80-04E25-00N81-04WBeaufort I Visibility3.5 miles5-62/300700168025-12N80-46W25-12N81-10W3.5 miles7-82/310700090025-0080-45WFlamingo3.5 miles

Cetacean observations (refer toFig. B1):

A‑2/28 104816 bottlenosed dolphins,Tursiops truncatus. 6 miles outside our course, headed west—rode bow briefly. Large concentrations of sea birds in area. One porpoise freeze branded N-1 on dorsal fin.B‑2/29 11002 right whales directly ahead of vessel headed NE—40-foot female? with calf. 2 bottlenosed dolphins accompanying the whales were riding pressure wave off whale's head.C‑2/29 140025-30 spotted porpoises,Stenella plagiodon, 1.25 miles outside our course, heading 240° mag. Did not ride bow wave.D‑2/30 13008 bottlenosed dolphins,Tursiops truncatus, 200-300 yards inshore of our course, milling in area of concentrations of mullet and other small schooling fishes, dolphins (porpoises) and birds feeding on fish.

[13]If latitude and longitude are not readily available, record best available position, for example 5 hours at 10 knots, SE of Miami.

[14]Any oceanographic or bathymetric information obtainable at the time of sighting may be significant. Such measurements as water depth, presence of large fish schools, or deep scattering layer/organisms (DSL) characteristics of the bottom (e.g., flat sand plain, sea mount, submarine cliff), surface temperature, depth of thermocline, and salinity should be included if available. In the Pacific, similar data have been used to demonstrate reliable associations there between saddleback dolphins and significant features of bottom relief and relationships between the onset of their nighttime deep diving (feeding) patterns and the upward migration of the scattering layers.

[15]Sometimes two or more species of cetacean are found together. If more than one species is sighted, try to identify each. Give both common and scientific names of each, and even if you cannot identify the animal(s) describe, sketch, and, if possible, photograph them and fill out the rest of the sighting report.

[16]Describe any tags seen (see Appendix A) and state their size, shape, color, and position on the animal's body and any symbols or numbers they contain.

As we discussed briefly in the introduction to this guide, whales, dolphins, and porpoises sometimes "strand" or "beach" themselves, individually or in entire herds, for a complex of still incompletely understood reasons. Though the reasons suggested for these strandings appear almost as numerous as the strandings themselves, two tenable generalizations have recently been proposed.

Strandings of lone individuals usually involve an animal which is sick or injured. Mass strandings, involving from several to several hundred individuals, appear to be far more complex and may result from fear reactions, from extremely bad weather conditions, from herd-wide disease conditions, or from failure of the echolocation system due to physiological problems or environmental conditions which combine to reduce its effectiveness, to mention only a few.

Whatever their causes, however, cetacean strandings usually attract crowds and elicit much public interest and sympathy. There are frequently attempts to save the lives of the animals involved.

Individually stranded cetaceans rarely survive, even if they are found soon after stranding and transported to adequate holding facilities. This does not mean that every attempt should not be made to save them.

In mass strandings, some individuals may be entirely healthy, and if they are found soon enough after stranding, properly protected and transported, and correctly cared for in the initial few days after collection, they may survive in captivity. Attempts to rescue all the animals in a mass stranding by towing them out to sea have almost always been frustrating because the animals usually swim repeatedly back onto the beach.

If you discover a stranding and before you become involved in an attempt to save a live stranded animal or to collect data from a dead one, you should be aware of the following:

Marine mammals are currently protected by law.Under provisions of the Marine Mammal Protection Act of 1972, it is unlawful for persons without a permit to handle, harass, or possess any marine mammal. It is within the authority of State officials and employees of the National Marine Fisheries Service to arrange for the care of live animals through certified institutions, such as many of those listed in Appendix E. (Even if the animals were not protected by law, any impulse to take them to backyard swimming pools, for instance, should be tempered by the knowledge that their chances of survival are far greater in an institution with the facilities and expertise to properly care for them.) The best general rule is to notify the nearest State or National Marine Fisheries Service office. If you prefer, however, you maycontact one of the institutions listed in the appendix and ask them to handle the situation. Some will already have permits to investigate strandings. Most will be anxious to help.

Althoughyou cannot remove the animal from the beach without a permit, you can help keep it alive until it can be removed. Here are a few hints.While waiting for help to arrive, endeavor to keep the animal as comfortable as possible. If it is not too large and surf conditions permit, it should be removed to shallow water where it is barely afloat.The buoyancy of the water will reduce the stress to the animal and will help to keep it cool and prevent overheating—a real danger to stranded cetaceans.

Whether or not the animal can be floated,care should be taken to protect it from sunburn, drying out, and overheating. If it is afloat, exposed parts should be frequently splashed down. If it is high and dry, it should be covered with damp cloth, particularly on the dorsal fin, flippers, and flukes, and the body and the terrain should be frequently watered to prevent the animal from overheating in the areas in contact with the sand or rock.

In any case, be careful to leave the blowhole free so that the animal can breathe. Note also that the eyes are particularly sensitive and susceptible to injury; they should be covered with a wet cloth and treated with special care.

With luck, this careful handling will be rewarded with the animal's being picked up and transported to an aquarium, where it can receive proper attention. But evenif the animal cannot be saved, collection and examination of the carcass can provide valuable information to scientists working on the biology of cetaceans, or on such problems as their disease conditions and the effects of environmental pollutants on them. Dead stranded cetaceans even in advanced stages of decomposition are also an important source of materials for museum study and display. Therefore, every attempt should be made to get the carcass into the best hands. Dead cetaceans, like the live ones, are protected by law and may not be removed without a permit.The procedure for obtaining permission to collect them is the same as that outlined for live strandings. The majority of the institutions along the western North Atlantic coast will respond to calls about live or dead strandings. Even if you are unable to contact an appropriate official, you can still collect some valuable information by identifying the specimen, using the following key, and by collecting measurements (seeAppendix D).

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