During which years were water hyacinth weevils and the water hyacinth moth released as bioagents?

The release of the water hyacinth weevils and the water hyacinth moth as biological control agents occurred between 1972 and 1977. This period marked significant advancements in the use of biological control methods aimed at managing the invasive water hyacinth, which has been known to cause severe problems in freshwater ecosystems, including outcompeting native species and disrupting recreational activities.

The purpose of introducing these bioagents was to reduce the population of water hyacinth by utilizing natural enemies, as opposed to relying solely on chemical herbicides or physical removal. The weevils feed on the plant and can significantly diminish its growth, while the moth's larvae damage the foliage, contributing further to the control efforts. Thus, choice B correctly identifies the timeframe during which these important biological control agents were actively released and became part of the management strategy for controlling water hyacinth populations in Florida and other regions affected by this invasive plant.