| Sumario: | Five sampling methods were evaluated for efficiency in estimating field populations of Megalurothrips sjostedti (Trybom) on cowpeas in Nigeria. The methods (sticky traps, water traps, sweep netting, shaking plants and the collection of whole plant samples) were judged on the basis of low sample variance, low cost and fidelity to absolute population trends. Shaking plants and water traps were the best sampling techniques on the basis of sample variance and cost. Shaking plants also showed the closest correlation with absolute population trends and is therefore recommended for rapid estimation of field populations of thrips. The performance of the usual alcohol method of sampling M. sjostedti on cowpeas (collecting racemes and flowers in alcohol) was not comparable with those of shaking plants and water traps, but was considered important because it sampled the infested structures, eliminating more transient visitors which might also be sampled by shaking plants.
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