How Deadly Are Stingrays?

The numbers behind the Crocodile Hunter’s death.

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“Crocodile Hunter” Steve Irwin died as a result of a freak stingray attack on Monday. The animal’s barbed tail delivers venom that causes excruciating pain, but it almost never kills. Several different figures for the number of recorded stingray-related fatalities have surfaced in the media, ranging from “about 30” worldwide, to “fewer than 20,” to “only 17.” Well, which is it?

No one really knows. It’s hard to keep track, and there isn’t enough interest in stingray attacks to merit an international monitoring effort. The reported numbers come from best guesses and the few publications that have addressed the issue. (The 17 figure comes from a textbook first put out by an Australian organization more than 30 years ago.)

If someone did want to record stingray fatalities, they might follow the example of the International Shark Attack File, which has been tallying shark bites for more than 40 years. Staffers at the Florida-based Shark Attack File start each day by combing through online article databases. Any leads get referred to a network of hundreds of biologists, doctors, and other informants stationed near coastlines around the world. A local rep makes contact with the victim of the attack—or the authorities, in the case of a fatal bite—and gathers as much information as possible. A standard Shark Attack File questionnaire looks for data on the weather, the tides, and how both the shark and the victim behaved before, during, and after the attack.

Widespread fascination with shark attacks has kept the Shark Attack File afloat for many years, but there aren’t many groups that keep track of other deadly animals. (Individual researchers have compiled records for some animals, like the mountain lions that have been causing problems out West.) It’s relatively easy to get data on animal-related fatalities in the United States, where the Centers for Disease Control publish a database of information reported from death certificates. Epidemiologists can determine how many deaths occurred from a specific animal by plugging various codes into the CDC database—”E-905.4,” for example, corresponds to “centipede and venomous millipede.”

A study in the journal Wilderness and Environmental Medicine used CDC data to find that 1,943 Americans perished from interactions with animals between 1991 and 2001. The paper doesn’t cover animal-related car accidents. Instead, it focuses on “various mechanisms that include bite, sting, crush, gore, stomp, buck off, fall on, peck, or scratch.” Hornets, bees, and wasps accounted for about a quarter of those deaths, with dogs making up around one-tenth. Two deaths were ascribed to “venomous marine animals”*—a rather vague category that includes the stingray. For comparison, three people were apparently nibbled to death by rats.

There is a big gap in the study’s findings. Almost half of the reported fatalities were ascribed to the catchall “other specified” category, which includes cows, horses, and many other species.

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Explainer thanks George Burgess of the International Shark Attack File, Robert Hueter of the Mote Marine Laboratory, and Ricky Langley of the North Carolina Department of Health and Human Services.

Correction, Sept. 6: In the original version, this piece incorrectly identified the category “venomous marine animals” as “venomous marine mammals.”(Return to the corrected sentence.)