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January 2004



The delicacy of Giant Bullfrog eating in Namibia

By Prof Daniel O Okeyo

Expect trouble if you indulge in Giant Bullfrog eating prior to the season's third rain. This is common sense to people who eat potentially poisonous frogs in the communal lands of northern and eastern Namibia.

African bullfrog. Image courtesy of the Honolulu Zoo.In the French frog-eating tradition only the feet, legs and thighs are eaten, amounting to between ten and forty percent of the frog. The reason for avoiding consumption of the rest of the body is unclear, but may be related to poisonous excretions from the skin of frogs. In Namibian traditional cuisine the entire frog is eaten, with the exception of the alimentary canal, which may be fed to dogs or poultry.

Very little formal information is available on the topic, but the practice may turn out to be unique to Africa, or at least to Namibia. Preliminary studies of the Giant Bullfrog eating practices and traditions were conducted in three areas of Namibia - Oshakati/Ongwediva, Okahao and Okambebe/Oshikango, between 1998 and 2001.

The Giant Bullfrog (Pyxicephalus adspersus Tschudi 1838: Ranidae) is reported to occur in central and northern Namibia, where it is called "omafuma" (plural) or "efuma" (singular). It has large tooth-like projections on the lower jaw, the adult eyes have horizontal pupils, non-webbed toes and longitudinal elevated skin folds. The frog's appearance changes markedly with age, presenting a challenge to researchers. Animals under 100mm are spotted and variable in colour with a single longitudinal dorsal streak from snout to tail. Large frogs are darkish green, but cream or pale yellow with orange in the limb region.

A significant finding was that, "premature" consumption - before "croaking and breeding" - causes "a burning inflammation of the urethra (more like Bilharzia) or some kind of temporary kidney failure" or "Dysuria". Locally this frog-induced disease is known as Oshiketakata.

Generally people are advised to wait until the Giant Bullfrogs start croaking or until "after the third rain" before eating them. Despite this caution people in some areas choose to eat frogs prematurely. However when they do so very specific anti-poisoning preventative measures are usually taken.


People from the Oshakati/Ongwediva area prevent poisoning by lining their cooking pots with pieces of dry wood from a tree locally known as Omuhongo (not to be confused by Omuoongo, the Marula tree). This wood apparently neutralises the frog poison while also preventing the frog skin from sticking to the pot bottom. "Nobody becomes ill from the disease when this cooking method is followed. In the Okambebe/Oshikango areas, where the Omuhongo tree appears to be unknown, people use the Omuva and Oshipeke trees instead. "Only two small pieces cut from Omuva or Oshipeke, when used to line the bottom of the pot while cooking frogs, will prevent the disease from attacking the culprit.

Photo of Pyxicephalus adspersis. Courtesy of Takeshi Ebinuma.
Pyxicephalus adspersis or Pyxie frog.

A less prevalent measure also used in Okambebe/Oshikano consists of "cutting off [the] frog toes before cooking". It is not yet established how this works.

Treatment for frog poisoning appears to vary by area. In the Oshakati/Ongwediva area "a piece of broken clay pot is placed over hot charcoal until red hot; the patient kneels within close proximity of the hot piece of broken clay pot and urinates on it. The patient feels relief from pain immediately." (A metallic hoe may be used if there is no clay pot available.) "Without the treatment the patient bears pain and sleepless nights for some time. How does it work? Some kind of chemotherapeutic, heat shock! It is speculated that perhaps heat disperses poison from concentrated parts of the patients' private organs.

In the Okahao and Okambebe/Oshikango areas treatment consists of medication supplied by local clinics or hospitals. However the Okahao study concludes that the "medicine does not seem to be working effectively. The problem eventually just vanishes by itself..."

It is recommended that further research be conducted into the "unexplained puzzles" that surround the consumption of this frog. The author invites interested life scientists, physical scientists and environmentalists to contact him for collaborative ventures.

In the meantime use this rule of thumb: Don't' eat a Giant Bullfrog before it croaks.

More information:

Daniel. O. Okeyo
Faculty of Science and Technology, University of Fort Hare
Private Bag X1314, Alice 5700, Republic of South Africa
Telephone: +27 (0) 40 602 2090/2252
Fax: +27 (0) 40 653 1669

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