As citizens across the United States, nay the world, emotionally prep for the cultural phenomenon that is Shark Week, let’s not forget culinary icon Julia Child and her somewhat niche relationship with sharks during World War II.

As a member of the Office of Strategic Services, the forerunner to the CIA, Child “found herself assigned to an experimental research project called the Emergency Sea Rescue Equipment Section,” writes Jennet Conant, author of A Covert Affair: Julia Child and Paul Child in the OSS. “She was developing a shark repellent that could be rubbed on pilots who had been down at sea.”

(U.S. National Archives and Records Administration)
(U.S. National Archives and Records Administration)

By 1943 at least 20 reports of U.S. Navy officers being attacked by sharks had reached the media, spreading alarm through the ranks of sailors and airmen who increasingly found themselves conducting dangerous missions over shark-infested waters, according to the CIA.

Enter Child and her cohort, Harold Jefferson Coolidge Jr., a scientist from the Harvard Museum of Comparative Zoology.

After a year of field testing and trying over 100 different substances — including, but not limited to, extracts from decayed shark meat — the pair landed on copper acetate as the most effective shark repellent.

The compound, mixed with black dye, was then formed into small cake-like disks that were, according to several 1943 memos, at least “60% effective in deterring shark bites.”

Giving off the scent of a dead shark when released into the water, the mixture was said to keep sharks at bay for six to seven hours and could be slathered on a life jacket, belt, or even on the body.

The Navy remained skeptical, and perhaps rightly so. Even Coolidge noted in May 1943 that “…none of us expected that the chemical would really function when the animals were stirred up in a mob behavior pattern.”

Nevertheless, morale was boosted among airmen and sailors at the prospect of a possible deterrence, and several orders were put in for the repellent.

Child later joked that the concoction was her “first recipe” in her cooking career, and in 2015 the CIA tweeted this formerly top secret “recipe” to the masses, giving us all a little more protection as we enter into Shark Week.