Studies on sampling larval populations of the Anopheles gambiae complex

Better sampling techniques are urgently required for estimating the population size and larval mortalities of the Anopheles gambiae complex. Some preliminary investigations into these problems were therefore made in Nigeria and Kenya. Knowledge of the type of distribution shown by larvae is important since it should enable more accurate sampling to be undertaken; consequently the biological distribution of larvae of the An. gambiae complex was investigated. Because there is often a need in control programmes to compare larval mortalities between populations in different types of habitat, attempts were made to construct time-specific survivorship curves and life tables so that instar mortalities could be calculated. Finally, results from estimating the size of larval populations in different habitats by a selective removal method and by a mark-release-recapture method were compared; the latter are considered more reliable.