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Operation Crossroads

The “Able” test of Operation Crossroads, the first atomic bomb dropped on the Bikini lagoon, on July 1, 1946. It was detonated at a height of 520 feet above the ground. Credit: Government photo in the public domain.
The “Able” test of Operation Crossroads, the first atomic bomb dropped on the Bikini lagoon, on July 1, 1946. It was detonated at a height of 520 feet above the ground. Credit: Government photo in the public domain.

For some reason I do not fear the Atom Bomb era that is with the world. There are and will be I am confident, still enough good men and women in this world to control properly the various advancements of men.

So wrote Smithsonian scientist Leonard P. Schultz on July 8th, 1946, from the U.S.S. Bowditch, the ship on which he had witnessed—one week earlier—the U.S. government’s detonation of an atomic bomb over the remote Bikini Atoll in the Pacific. Schultz was one of two Smithsonian scientists who formed part of Operation Crossroads, the beginning of a program of nuclear testing that stretched into the late 1950s.

a picture of a washington Post article. See caption below.
A Washington Post article from March 21, 1946, discussing Schultz and Morrison’s work with Operation Crossroads. Clipping from Smithsonian Institution Archives.

Leonard P. Schultz and Joseph P.E. Morrison were curators and seasoned field collectors at the U.S. National Museum (today called the National Museum of Natural History) in Washington, when, on January 28, 1946, the U. S. Navy asked the Smithsonian to send experts to the Marshall Islands—part of a team of botanists, zoologists, geologists, and oceanographers from universities, oceanographic institutes, and government research bureaus. After two weeks of hurried preparations, Schultz and Morrison left Washington, D.C., for California, where they joined the U.S.S. Bowditch.

The participation of Smithsonian scientists on military expeditions was not new. Indeed, Shultz had been on the 1937 U. S. Navy Expedition to the Phoenix Islands, and Waldo Schmitt had been assigned to the 1941 and 1942 Navy expeditions to the Galapagos. However, the size and scope of the Bikini surveys far exceeded any earlier Smithsonian/military cooperative projects.

The Bikini scientists were assigned to conduct a biological survey of the plants and animals on and around Bikini, Eniwetok, Rongelap and Rongerik Atolls, and to compile data on the abundance and distribution of organisms prior to the bomb tests. They were also charged with making further collections after the bomb tests, to compare with the earlier data. The majority of the biological collections would be deposited at the U.S. National Museum, while another set of specimens would be sent to government laboratories for radiology and histological studies. (In the end, the Navy ship carrying these government laboratory collections ran aground off the California coast, and all but a few of the specimens were lost.)

Leonard Schultz was curator of ichthyology at the museum and a specialist on the systematics of reef fishes and sharks. At each atoll, Schultz ran numerous collecting stations by treating the water with the chemical rotenone. He also dredged and went shark- and night-fishing.

Joseph P.E. Morrison. See caption below.
Joseph P.E. Morrison working aboard the U.S.S. Chilton at the Bikini Atoll, during the Bikini Resurvey of 1947. Credit: Smithsonian Institution Archives.

Professional fishermen assisted the ichthyologists with their work. Joseph Morrison, a curator in the Division of Mollusks, had broad interests in natural history and collected a wide variety of invertebrates from the lagoons and reefs, totaling some 200,000 mollusks and 8,000 miscellaneous marine invertebrate specimens for the museum collections. An ornithologist by avocation, he also went ashore to collect birds, mammals, plants and land invertebrates. Other scientists collected plants, mammals, and marine fish, while oceanographers conducted studies of currents, tides, and reefs.

Schultz and his colleagues discovered a number of new species, the type specimens of which reside today in the collections of the National Museum of Natural History. Among them is a Bikini Atoll moray, Enchelycore bikiniensis and a four-saddle grouper, Epinephelus spilotoceps (both described by Schultz, 1953).

Able Day

On the eve of Able Day, July 1, 1946, the U. S. S. Bowditch moved some twenty miles northeast of the blast site. All hands were called to attention shortly before the bomb was due to be dropped at 9am. The bomb, which was intended to test the effects on a standing fleet, was dropped from a B-29 airplane. It exploded about 520 feet above the surface of the water where the target fleet—composed of older U.S. capital ships, some captured German and Japanese ships, as well as surplus U.S. cruisers, destroyers, submarines, and other vessels—was congregated. Approximately 42,000 people—soldiers, scientists, journalists, congressmen and other VIPs—witnessed the bomb.

Schultz’s diary entry from Able Day, July 1, 1946, indicating that he posted letters to Secretary of the Smithsonian Dr. Alexander Wetmore, and several to his wife and to others, and that he had a tooth pulled two hours after the atomic bomb test. Credit: Smithsonian Institution Archives.
Schultz’s diary entry from Able Day, July 1, 1946, indicating that he posted letters to Secretary of the Smithsonian Dr. Alexander Wetmore, and several to his wife and to others, and that he had a tooth pulled two hours after the atomic bomb test. Credit: Smithsonian Institution Archives.

Schultz and Morrison, who watched the explosion from the ship’s drafting room, were among those who were issued goggles to protect their eyes; others were told simply to cover their eyes with their arms. Few other precautions were taken. Schultz was doubtful whether the goggles would protect him, so he covered one eye and observed the explosion with the other. “Then with the goggles off,” he wrote in his diary, “I watched the whole aftereffects with both eyes. But neither eye was blinded.” He recalled how bright the flash was, and how he felt “a slight warmth” on his face. “Two minutes after the flash,” he reported, “came the noise – a low boom.”

After the detonation, Schultz and other scientists waited two days to return to the atoll. He and his fellow naval observers recorded the number and distribution of organisms killed. Schultz returned to D.C. on July 22, a few days before the second test. After five months in the field, he had collected more than 38,000 fishes, representing more than 300 species.

Baker Day

On July 25, 1946, the U.S. Navy conducted the second atomic bomb test, on what was called Baker Day (Able and Baker were the first two letters of the joint Army/Navy phonetic alphabet, which was used from WWII until 1956, when it was replaced by the NATO phonetic alphabet: Alpha, Bravo, etc.). This second atomic bomb was detonated under the water, and caused far more extensive damage than the first. Watch a film clip of the Baker explosion here.

While few dead fish had been seen following the Able blast, many perished in the Baker Day underwater test. The Geiger counter readings were so strong that Morrison and the other scientists waited nearly a week to return to the atoll. They picked collecting stations similar to those they had sampled in the spring of 1946, which they anticipated were contaminated with radioactivity—so as to be able to determine “an index of abundance” or how many fish per square yard could be collected to reveal any reduction in the fish population after the Baker test.

Scientists on the Bikini Resurvey—from left to right, Leonard Schultz kneeling, Hiatt, A.C. Cole, and V.E. Brock—collecting specimens (mostly parrotfish). Credit: Photo courtesy of the Division of Fishes, National Museum of Natural History, Smithsonian Institution.
U.S. National Museum curator Leonard Schultz, kneeling at right, reviews some (mostly parrotfish) specimens collected as part of the Bikini Resurvey in 1947. From left to right, Vernon E. Brock (Director of Fish and Game Division for the territory of Hawaii), A.C. Cole (professor of zoology and entomology at the University of Tennesseee), R.W. Hiatt (U.S. Fish and Wildlife Service), and Schultz. Credit: Photo courtesy of the Division of Fishes, National Museum of Natural History, Smithsonian Institution.

The Bikini Resurvey of 1947

One year later, on June 28, 1947, Schultz and Morrison again left Washington, D. C., for Bikini Atoll, to conduct a resurvey. This time they were accompanied by Frederick M. Bayer, a young, newly hired invertebrate zoologist at the museum specializing in corals. This Smithsonian team conducted a wide range of studies on the 1947 resurvey. Schultz led statistical and systematic studies of the fish populations; radiological investigations were also carried out; and the embryology of sea-urchins was studied, in order to determine possible effects of radiation on reproduction. The U.S. Geological Survey directed the sinking of the deepest core drilling yet undertaken in the Pacific. These core samples—from 1000 to 2500 feet into the limestone reef—were to provide data to test competing theories of coral reef formation. The cores were not deep enough to reach basement rock, however, which was needed to solve the controversy. Finally, in 1950 a core sample was taken at 5000 feet, reaching beyond the reef limestone to the basement rock, which proved to be basalt—and Darwin’s theory that coral reef formation was volcanic in nature was finally proven. The resurvey also used the Navy’s new underwater television equipment to observe on screen the color pattern of fishes, which aided the process of species identification and made it possible for the biologists to observe aquatic animals in their natural habitats.

The Smithsonian team also collected additional biological material, particularly marine invertebrates. Morrison and Bayer made extensive collections, and Morrison also collected birds and the few land vertebrates that could be located. They hoped to build a collection that would be useful in determining whether any morphological changes had taken place since the explosion. Bayer in particular was encouraged to make color records of coral crabs and other colorful invertebrates.

Despite this large scientific effort, Schultz and Morrison did not think that much could be concluded within a year of the blast. Many organisms had died from the impact or from radiation poisoning. But little mutation was seen. They speculated that competition on the reef was so keen that any aberrations were gobbled up long before they could be collected by scientists. And they noted that it was difficult to separate out the many types of damage done to Bikini Atoll—oil spills from sunken vessels covered coral reefs and shellfish beds, while the debris left by 45,000 human beings had been dumped into the lagoon. Movement of ships and anchors had increased the turbidity of the water. But clearly radioactivity had entered the food chain. Plankton glowed on photographic plates, as did the intestinal tracts of the fish that fed on them. Only long term studies would show if the atoll would ever return to the ecological balance it enjoyed before Able Day.

March 7, 2006, marked the sixtieth anniversary of the forced relocation of all 167 native inhabitants of Bikini Atoll in preparation for Operation Crossroads. They were never allowed to return, due to persistent radioactivity. Today most Bikinians and their descendants live elsewhere in the Marshall Islands. On August 1, 2010, the World Heritage Committee inscribed the Bikini Atoll Nuclear Test Site on the World Heritage List for the role that the tests played in shaping global culture in the twentieth century.

The Smithsonian Bikini Collections

composite image. See caption below.
[Left] Captain Christian L. Engleman, captain of the U.S.S. Chilton, and CSF (chief ship fitter) R.F. Mullen in 1947 in the Bikini lagoon, with a giant clam (Tridacna gigas), the largest living bivalve mollusk and today one of the most endangered. Credit: Smithsonian Institution Archives. [Top Right] The Synchiropus morrisoni (USNM 141126), also a holotype, was collected on August 7, 1946, from the Bikini Atoll, station S-46-308. Dorothea Schultz (Leonard’s wife) drew the specimen. This species was, as Shultz et al wrote, “Named in honor of Dr. J. P. E. Morrison, associate curator of mollusks, U.S. National Museum, who spent the summers of 1946 and 1947 at Bikini.” Credit: Photo courtesy of the Division of Fishes, National Museum of Natural History, Smithsonian Institution. [Bottom Right] A Pacific parrotfish collected during the Bikini Resurvey in 1947. First identified in 1840, this specimen was known as Scarus jonesi at the time of Operation Crossroads and is today referred to as Chlorurus frontalis. The scientist is using a pair of forceps to hold the dorsal fin, to show off all the dorsal rays. Credit: Photo courtesy of the Division of Fishes, National Museum of Natural History, Smithsonian Institution.

The Bikini Survey and Resurvey brought many new collections to the National Museum and stimulated a great deal of research on the flora and fauna of the region. For the Fishes collections, it was one of the more significant collecting efforts of the twentieth century. Despite some restrictions on the release of scientific information, Schultz and other systematists and geologists produced significant studies from these collections, including especially Leonard Schultz’s Fishes of the Marshall and Marianas Islands, which was published as Bulletin 202 of the U.S. National Museum. Additionally, long term relations were established between the Smithsonian, the Office of Naval Research, and the Atomic Energy Commission. Schultz continued his close ties with the Navy through his work on the Shark Research Panel, documenting shark attacks, and Frederick Bayer was part of a team that conducted scientific investigations and survey work in Micronesia in the early 1950s, sponsored by the Office of Naval Research. In the late 1970s the A.E.C. was still funding contracts with systematists to work up the Bikini collections.

The U.S. testing program in the Marshall Islands had a profound impact on the geology and biology of the atoll. Today the Smithsonian’s collections document the extent to which the diversity of marine life was affected by the atomic blasts, providing researchers who continue to ­study the health of the ecosystem with a means to compare species extant today with those collected before the tests. In 2008 a survey conducted by a team of international scientists determined that while some coral species are flourishing, many are locally extinct.

The atoll surveys provided a rare opportunity to observe an entire ecosystem in flux—continuing the type of work Smithsonian scientists have been undertaking for more than a century. In 1910-12, for example, Smithsonian biologists undertook a comprehensive biological survey prior to the completion of the Panama Canal. These early environmental impact surveys helped form the foundations of our modern understanding of biodiversity.

This essay includes material excerpted and adapted from: Pamela M. Henson, “The Smithsonian Goes to War: The Increase and Diffusion of Knowledge in the Pacific,” in Science and the Pacific War, ed. Roy M. MacLeod (Great Britain: Kluwer Academic Publishers, 2000), pp. 27-50.

Watch scientists on the Bikini Resurvey project of 1947 collecting specimens. Clip courtesy of Smithsonian Institution Archives



Another page from Schultz’s diary entry from Able Day, July 1, 1946, describing the blast and featuring a drawing of the bomb test. Credit: Smithsonian Institution Archives. The famous image of the second Operation Crossroads bomb, the “Baker” explosion, conducted ninety feet underwater, on July 25, 1946. The radioactive fallout was so much more concentrated after this second test, that a third “Charlie” test, scheduled for 1947, was cancelled. Credit: Government photo in the public domain.
Scientists at the Bikini Atoll during the Bikini Resurvey of 1947. Leonard Schultz is third from left in the front row. Credit: Smithsonian Institution Archives. A large sea urchin specimen, probably Heterocentrotus trigonarius (Lamarck, 1816), collected from the Bikini Atoll during the Scientific Resurvey in 1947. Credit: Smithsonian Institution Archives.
An African coris or clown wrasse (Coris gaimard) collected during the Bikini Resurvey in 1947. Common in aquaria today, the fish was first identified in the early nineteenth century. The females, like this one, have a bright yellow caudal fin. Scientists typically include a unit of measure when photographing specimens. Credit: Photo courtesy of the Division of Fishes, National Museum of Natural History, Smithsonian Institution.Members of the Bikini Resurvey team of 1947 swim in the shallow waters of the Bikini Atoll collecting specimens. Credit: Smithsonian Institution Archives.
Cirripectes fuscoguttatus Strasburg & Schultz, a spotted blenny, was first discovered during Operation Crossroads. This is the holotype (USNM 113634), the actual fish that Schultz and Strasburg used to describe the species. It was collected at Rongerik Atoll on 29 June 1946 by Schultz and Captain Earl H. Herald. Credit: Photo courtesy of the Division of Fishes, National Museum of Natural History, Smithsonian Institution.These Trapezia crabs, illustrated by Frederick Bayer, who studied and collected reef corals during the Bikini Resurvey of 1947 and documented the crabs associated with them. He made watercolor sketches of the various color patterns of these crabs for his colleagues at the Museum. Credit: Image courtesy of Department of Invertebrate Zoology, National Museum of Natural History, Smithsonian Institution.

More about
the Bikini Atoll

This drawing, showing life on the island during Operation Crossroads, with a map of the Bikini Atoll in the inset box at lower left, was made for the Bikini Survey Cruise Book, 1947. Credit: Smithsonian Institution Archives.

“Bikini Atoll in shape resembles a bathtub, except that its sides are cut through by several deep channels. It is about 22 miles long by 13 miles wide, inclosing a lagoon whose depth is mostly 180 feet with a few areas down to 200 feet. Rising from the lagoon floor are large coral heads, a few of which come near the surface, whereas around the margins of the atoll reef are more coral heads that reach the surface. The lagoon floor slopes gradually upward from its deeper parts to those areas exposed during the low tides. The bottom is composed of loose sand, fragments of calcareous algae, and coral remains, on which are growing a great variety of sessile (or permanently attached) invertebrates, aquatic algae, and into the rocky fragments worms burrow. In otherwise unused crevices, fishes hide. Where the corals and algal growths are luxuriant, over 200 species of fish occur.”

From Leonard P. Schultz, “The Biology of the Bikini Atoll, With Special Reference to the Fishes,” Annual Report of the Smithsonian Institution for 1947, pp. 301-316.

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