The Causes
As bee friendly habitat has turned into housing tracks and monoculture farms, bees have lost food sources and been exposed to harmful pesticides by industrial agriculture. The resulting poor nutrition and weakened immune systems make them vulnerable to disease and deadly parasites such as the varroa mite. Changes in climate may cause flowers to bloom early or late, and native bees that depend on that bee emerge to find no food.
The monocultural environment of U.S. farmlands exacerbates the problems. Soybeans and corn, pretreated with pesticides, account for more than 50 percent of all cropland harvested in the U.S. (USDA 2012). From grain fields to almond orchards, fields are bare of weeds and companion plants of any kind, the better to accommodate harvesting machines.
Many of these lands were previously diverse family farms, which supported pollinators with mixed crops and family gardens of fruit trees, flowers and vegetables. And before that, these lands were the diverse bee environments that existed prior to the arrival of the European settlers who introduced the honey bees.
An exact cause of CCD has never been defined. This is because the cause appears to be a complex of the interconnected pressures from pesticides, diseases, pests and climate change. These problems are worsened by the poor nutrition and the stresses of the commercial pollination business. Millions of beehives are shipped around the country for large pollination events such as the annual pollination of the $22 billion California almond crop, which represents 80 percent of the world almond supply. Over 70 percent of the nation’s beehives participate in the almond pollination event which has contributed to the spread of varroa mites and the viruses they carry.
In the trio of pesticides, disease and pests, pesticides are the variable underlying and contributing to the others.