The problem of rat damage done by Norway rats, black rats, and Polynesian rats to sugarcane in Hawaii is discussed in terms of damage description and economic impacts. Control methods largely depend on the use of various anticoagulant rodenticides formulated on rolled oats with addition of paranitrophenol as a mold inhibitor. These baits are placed in around the periphery of fields in three types of bait stations: temporary stations made of cardboard treated with wax, inverted “T” bait dispenser, and “L”-shaped bait dispenser, with the latter two typically made of plastic pipe. Baiting strategies are described, and the problem of bird consumption of anticoagulant baits is noted. Occasionally, baits made from rolled oats treated with thallous sulfate are used, but prebaiting is required for these to be effective. Better rodenticide baits are needed, especially for the Polynesian rat, and it would be advantageous to have such a bait that could be applied in sugarcane fields by aircraft.

The East African nations of Ethiopia, Somalia, Kenya, Uganda, Tanzania, Malawi, Mozambique, and Zimbabwe encompass a widely varied topography, and climate from tropical to temperate. Where soil and rainfall permit, agricultural crops are grown. For the most part, farming is of a subsistence nature being small single family plots, which make up about 90% of the farming in these nations. Large farms in Kenya and Zimbabwe are generally confined to the temperate uplands, and elsewhere there are large government agricultural schemes growing food crops like rice and sugar cane. Almost all of the nations of East Africa have chronic food shortages. The impacts of the most economically important rodent species, including the multimammate mouse, grass rat, Norway rat, roof rat, and house mouse, as well as these species biology, are summarized. A 2-year rodent control program in Somalia, funded by FAO, began in 1981 and is briefly described, as are recent rodent control projects in other East African countries. A positive outcome of these projects is that they have incorporated education for responsible national staff who in turn will train fellow workers. Long-term support for such efforts is needed.

The collared pika, Ochotona rufescens, has been recorded as a serious pest in apple orchards in the uplands valley of Ziarat in Baluchistan. In the winter, when the natural vegetation is lacking, the pikas debark the apple tree trunks or branches resulting in the killing of the tree and reduced fruit production. In summer, damage to wheat, corn and potatoes is also very severe. It is estimated that pikas cause hundreds of thousands of dollars (US) in annual apple production losses. The apple production in Baluchistan accounts for about 35 percent of the total provincial income through food production. During the six years (1974-1979), the winter of 1973-74 was noted for heavy damage to apple trees and thereafter it declined steadily. The control measures evaluated were of various kinds among which repellent "Ostico" was very effective in protecting the trees. Poison baiting with brodifacoum (0.005%), Vacor (1%) and thallium sulphate (1%) were also effective in reducing the pika population. To alleviate damage caused by pikas, the farmers also practice some traditional protective methods which in some cases are quite effective but very laborious.