Giant African Snails & Fake Facts: A Cautionary Tale

Giant African Snail (Achatina fulica)

A recent Australian news feature on giant African snails led this blogger to undertake some casual research on this remarkable species, known to scientists as Achatina fulica.

The quest led to discovery of a chunk of false information, hiding in plain sight on Wikipedia. It served as a reminder that “fake news” isn’t the only problem we encounter on the Web and in social media generally; “fake facts” are also sitting out there on a myriad of websites, just waiting to be discovered.

The news feature that aroused my interest was “Giant African snails: A biosecurity threat too big to ignore for Australian agriculture,” appearing on Australia’s ABC News Rural on May 29. The feature itself was fine; I didn’t have any problems with it. Among its fascinating tidbits:

·       The fast-breeding world's largest land snail, the giant African snail, is considered one of the world's top invasive species

·       It can reach up to 20 centimetres in length and consume entire plants — posing a threat to native species

·       Previous detections of the species in Australia have been eradicated but Ausveg biosecurity officers are warning Australian farmers that it is a threat they need to be aware of

Nowadays, when folks find something of interest on the Web and want more info, they often use a well-worn route to further discovery: first search on Google, then read an article on Wikipedia. Unfortunately, many people often end their inquiries at this point. But there’s no guarantee that what you are reading on Wikipedia is accurate. Often you need to check the sources cited there to make sure what you are reading is true.

Sadly, the article on “Achatina fulica” contains some “fake facts.” As often happens, the bogus info appears in a paragraph without any footnotes:

In some regions, an effort has been made to promote use of the giant African snail as a food resource in order to reduce its populations. However, promoting a pest in this way is a controversial measure, because it may encourage the further deliberate spread of the snails.

One particularly catastrophic attempt to biologically control this species occurred on South Pacific Islands. Colonies of A. fulica were introduced as a food reserve for the American military during World War II and they escaped. A carnivorous species (Florida rosy wolfsnail, Euglandina rosea) was later introduced by the United States government, in an attempt to control A. fulica but the rosy wolf snail instead heavily preyed upon the native Partula, causing the extinction of most Partula species within a decade.

Some additional research using the article’s general references led to the discovery that the above passage was rife with errors or possibly deliberate distortions. The second paragraph is the problematic one. It conflates a number of real facts and mixes in some bogus ones.

Further research revealed that the American military was NOT responsible for introducing the giant African snail in the South Pacific. (Those of you familiar with the U.S. and its military will realize that (a) the United States does not regard giant African snails as a food source and (b) the American military would never even think of developing a food reserve of this kind. Potatoes, maybe, but not land snails.)

The giant African snail appeared in different parts of the South Pacific at various times, mostly prior to World War II. It turns out that some Japanese enjoyed eating them. And while, the Japanese government realized the danger of this invasive species and barred its citizens from importing the giant snails, some people brought them into Japan covertly. Other Japanese, apparently including Japanese soldiers during World War II, either deliberately or accidentally may carried giant African snails to various Pacific islands.

One American study, “Studies on Control of the Giant African Snail on Guam” by Gordon D. Peterson, Jr. (Hilgardia: A Journal of Agricultural Science, July 1957), cites a report about the snail’s introduction on Guam:

Guerrero's report presents evidence that Achatina fulicamay have been introduced during the Japanese occupation. He gives an account of his interview with one Jose I. Shimizu, a Japanese half-caste and an old resident of Guam. Shimizu stated that his father, a Japanese national, had learned of the accidental importation of snails with sweet potatoes from the island of Rota in 1943 and had informed the Japanese Governor-Commandant of his discovery. Shimizu also stated that while he was imprisoned at the Island Command Stockade following American reoccupation of Guam, he overheard Japanese prisoners of war telling of their having eaten snails while they were hiding in the jungle.

The same study says that if American forces introduced the giant snail into Guam after taking control of the island from the Japanese, it would have been done accidentally. The snails are very talented at hitching rides in loads of vegetables, hollow pipes, etc.

Another report on “Invasive Species of the Pacific” by the South Pacific Regional Environment Programme (Samoa, 2000) notes that elsewhere in the Pacific, specifically in Hawaii, the U.S. government did introduce a number of species of carnivorous snails in an unsuccessful bid to eliminate the giant African snail. The unfortunate result was serious damage to native snail species – and A. fulica was apparently unaffected by its carnivorous cousins.

Bottom line: Be careful about accepting information uncritically from Wikipedia and similar websites. Always check the sources, and the sources of the sources. You’ll be glad you did.