That isn’t a joke–The Liberian president has declared a state of emergency:

“MONROVIA, Liberia (AP) — Liberia’s president declared a state of emergency over an invasion of crop-eating caterpillars that has affected 350,000 people in the West African country.

President Ellen Johnson Sirleaf told lawmakers Monday night that the pests “have invaded our country with the potential to set back our progress in the production of food and export crops.”

“This is indeed a crisis and I hereby declare a state of national emergency with particular emphasis on the existing and potentially affected counties,” she said.

The inch-long (2-3 centimeter) pests, which have been identified as army worms — the caterpillar stage of a moth — are clogging wells and waterways with excrement and devouring vital crops including banana, plantain, coffee and cocoa.”armyworm

News reports identify the invaders as Spodoptera exempta, the African Armyworm.  The caterpillar of this moth can suddenly become very abundant when conditions are right, and devastate all the crops in an area.

Additionally, because of the high numbers of caterpillars, they often have to move to find new food–and they and they all go together. Hence the name ‘armyworm’.

This photo from the Armyworm Biological Control Consortium gives you a sense of the kinds of damage these ‘pillars can do. They are eating and pooping as they go, which is why wells and waterways are being clogged.

The ABCC has a nice overview of the devastating nature of armyworms, and also the attempts to control it biologically. Sadly, the only way that this outbreak can be controlled is probably insecticides.  Biological control won’t act fast enough to save Liberians’ food and water.

I have no information on how anyone can help; Liberia has asked for help from FAO (UN Food and Agriculture Organisation).

EDITED 2/6/09 TO ADD: The Liberian Journal is now reporting that the species is Achaeae catacaloides, also a noctuid moth but in a different subfamily from Spodoptera. Thanks for the tip, Ted!

Posted by Gwen Pearson

Writer. Nerd. Insect Evangelist. Have you heard the good news? BUGS!


  1. Just wait till the navyworms arrive.

  2. Hate to sound like a broken record here, but I’m pretty sure that yeah, these cats are edible. There is documentation of Spodoptera consumed in Native North America and Africa. I could find the citations if anyone’s interested.

  3. They probably are, but right now it sounds like people are just overwhelmed by the numbers.

  4. eeuw. and I thought greasy, grey cutworms were ugly!


  5. Dr Peter Merrett January 31, 2009 at 2:36 am

    I still don’t think these are Spodoptera exempta. Those guys never ate lettuce, collards and cocoa leaves in East Africa. And since when did Liberians rely on only those crops for food?


  6. Well, I only have official press releases to go by–no actual specimens. If you have a more reliable source of taxonomic info, let me know!

    The emergency declaration states that it’s crops for exports that are being attacked, as well as food and water. That would cause a huge decrease in income for the country.

  7. The Liberian Journal is now reporting that the species is Achaeae catacaloides, also a noctuid moth but in a different subfamily from Spodoptera.

    Good call Peter!

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