What occurrence related to honey bee colonies was identified in 2006?

The occurrence related to honey bee colonies that was identified in 2006 is Colony Collapse Disorder (CCD). This phenomenon is characterized by the sudden disappearance of a large number of worker bees from a colony, leaving behind the queen, brood, and food stores. CCD drew significant attention because it was alarming and seemed to lead to the decline of bee populations in various regions, particularly in the United States. The cause of CCD was complex and multifaceted, involving factors such as pesticides, habitat loss, and diseases, and it represented a concerning trend in beekeeping and agriculture due to the important role bees play in pollinating crops.

Other events listed, such as the introduction of Small Hive Beetles, Tracheal Mites, and Varroa Mites, are known threats to honey bee health, but they were recognized and documented prior to 2006. CCD marked a unique and urgent crisis in the bee community and agriculture occurring specifically around that time.