Fish Poisons or Piscicides

David S. Seigler Department of Plant Biology University of Illinois Urbana, Illinois USA

Outline - Fish Poisons (Piscicides) Piscicides o none important commercially o rotenoids active at 1 part in 10 X 10 6

Reading CHAPTER 12 and lecture material

Introduction Many plant products are used in "primitive societies" to capture or kill game. These range from those used to coat or tip arrows and spears to those used to poison or stun fish (sometimes called piscicides or barbascos). We have benefited from these unusual uses (to us) in that we use these compounds medicinally and for insecticides.

Plants also have been used to capture fish in many cultures (including former European cultures). The fish poisons used generally render the fish helpless, but not poisonous to the people that eat them. Often, as little as 1 part in 10 million is effective in stunning the fish.

Preparing to capture fish with plant-derived piscicides in Venezuela

Trees of Ghana

Preparing fish poisons for use in Hawaii Chuck Kritzon, Fishing with Poisons,

One of the most effective types involves plants of the Fabaceae or Leguminosae of the genera Derris (Asian), Lonchocarpus (South American), and Tephrosia. The active compounds from these plants are called rotenoids. They are used today in our culture as insecticides.

Derris elliptica, Fabaceae Pacific Island Ecosystems at Risk (PIER) Photo by Agnes Rinehart

Lonchocarpus purpureus, Fabaceae

Other rotenoid-containing plants Tephrosia virginiana, Fabaceae

Many other plants used as fish poisons contain "saponins" or organic soap-like materials. One of the most famous fish poisons involves fruits of the genus Barringtonia (Lecythidaceae or Barringtoniaceae).

mages/bar_asi_cu.jpg

Piscidia piscipula, Fabaceae F.E. Köhler, Medizinal Pflanzen Gera- Untermhaus, 1887 Piscidia piscipula leaf material has long been used to capture fish in Mexico and Central America. The active principles are also known to be rotenoids.

Menispermaceae Many plants of the Menispermaceae have alkaloids. Although some of these have been used to capture fish, those of two genera commonly used as piscicides, Anamirta and Cocculus, however, contain picrotoxins, a complex structural group of sesquiterpenes.

Anamirta cocculus, Menispermaceae F.E. Köhler, Medizinal Pflanzen Gera- Untermhaus, 1887

Cocculus carolinus, Menispermaceae

Soapberry, Sapindus drummondii, Sapindaceae Sapindaceae and Sapotaceae (mostly saponins) often are used.

Monilla or Mexican buckeye, Ungnadia speciosa, Sapindaceae

Acacia or wattle species have been used for fish poisons in Australia. To date, the active compounds have not been identified.

Fish poison wattle, Acacia holosericea Fish poison tree seedpod, Acacia ditricha Chuck Kritzon, Fishing with Poisons,