Caution and Optimism

From Vancouver, British Columbia Mark Winston writes of the precarious condition of the honey bee, and he cautions that the same conditions that have so seriously affected the bees could likewise endanger humans as well. Writing in the New York Times, http://www.nytimes.com/2014/07/15/opinion/bees-and-colony-collapse.html, Winston explains that about a third of the managed honey bee hives worldwide collapse and die each year. Winston is optimistic that by observing the bees we can avoid a similar fate in humankind. The loss of honey bee colonies does not have a singular cause, but instead the deaths result from the complicated relationships between many elements. Winston lists some of these including pesticides applied to agricultural fields and pesticides used in bee hives by beekeepers to control parasitic mites; fungal, bacterial, and viral diseases; nutritional deficiencies caused by monocultural crop planting practices; and commercial beekeeping activities. He explains that the problem arises from the interactions among the many elements which sometimes result in a synergy or multiplying of the harmful effects, resulting in the compromise of the honey bees’ immune systems.

Winston explains that the pharmaceuticals that humans use often react in similar synergies as the pesticides injuring bees. He also cautioned that excessive cultivation, chemical use, and habitat destruction threaten the honey bees, pollinators so important for our food production. A Simon Fraser University study conducted on Canadian canola fields illustrates the value of feral bees. Farmers who planted a field earned $27,000 in profit using standard, modern agricultural practices while farmers who left one third of their equivalently sized farm unplanted to provide food and habitat for bees earned $65,000 per year. Modern industrial agriculture designed to optimize crop yields is often stressful on bees and beneficial insects. Beekeepers also may stress their bees through severe honey harvesting or excessive pollination travel. Meanwhile, signs of recovery of species weakened by environmental chemicals and habitat loss exist. Today’s photo reveals a bald eagle, once rare in the Mid-South, surveying Peace Farm from its lofty perch.

--Richard

What Happened to the Hive?

A beekeeper asks for my thoughts about the loss of a colony of bees. He explains, “I had a good sized colony, three boxes high, bottom and part of second were a mix of brood and honey, and top was all honey. Earlier in the summer I had another six inch super on top which was filled.” In late August, finding his hive empty, he explains, “There was no sound, in fact there was not one bee, and there was not one dead bee either. Every bee was gone.” However, on the day before, the hive showed much bee activity. Attempting to understand colony losses is curious and worthwhile.

The complete abandoning of a bee hive, called “absconding,” is not common in the temperate zone unless conditions make the hive completely undesirable. Colony Collapse Disorder has drawn much attention in recent years, but the conditions here don’t fit its definition. With CCD, there is a loss of older adult bees, but the hive is left with a queen, nurse bees, and brood. A very common cause of the loss of a colony of honey bees, however, is colony collapse due to Varroa mite infestation. This is particularly common in the time period of late summer, as in this late August case. Honey bee colonies grow rapidly in the spring to produce large populations of foragers to harvest nectar and pollen while flowers are in bloom. The queen slows her egg laying in the summer and the colony population gently declines. Parasitic Varroa mite populations follow a different pattern. Mites in a bee hive increase in number gradually throughout the year. By late summer bee numbers are declining while mites are increasing. As the Varroa mites bite bees, they spread bacterial, fungal, and viral infections throughout the colony, eventually killing it. Why was there plenty of hive activity the day before? Robber bees were removing honey stores. Today’s photo shows guard bees challenging incoming foragers. Guards are absent from dead hives.

--Richard

Plums in Bloom

The plums are the first bright white-blooming trees to appear in the woods early in the spring. These members of the rose family grow in woodlands, fencerows, and old fields. The roses are important bee plants, providing ample amounts of nectar and pollen. There are numerous species of plums in the Mid-South including the wild plum and the Chickasaw plum, thought to have been cultivated by the Chickasaw Indians and early settlers. Many domestic plums have escaped into the woods, often forming thickets of white-blooming, low trees. Many of the domestic plums require bees to cross-pollinate the blossoms. The early bloom of the plums comes at an important time for honey bee colonies rapidly expanding their spring populations. After the bloom of the plums, a series of other fruiting trees in the rose family will come into bloom: pear, apple, cherry, peach, and crabapple. The almond tree, cultivated in California, is also a rose. All except the peach, which is usually self-fruitful, require pollination from bees to produce fruit. If you click on today’s photo, you can see honey bees actively foraging a plum tree. Some bees are collecting nectar, and others are collecting pollen.

A report has been released which indicates that Colony Collapse Disorder still persists after four years of honey bee die-offs in the United States and Canada. The report reveals that continuing CCD losses coupled with a more severe winter than normal may bring record over-winter colony losses this year. The study found bee pollen and hives laden with pesticides. Many of the pesticides are systemic agents which are designed to be taken up by the plants and carried throughout the plant. It is felt that the systemic pesticides are brought back to the hive by honey bees foraging for pollen to feed to the brood. The report can be followed at http://news.yahoo.com/s/ap/20100324/ap_on_sc/us_food_and_farm_disappearing_bees. Hopefully, this and similar reports will make more of the public aware of the effect certain pesticides have on the pollinators.
--Richard

A Collapsing Honey Bee Colony

Accompanied by beekeeper and photographer Brandon Dill, I am checking the supers on some strong hives. Any hive with large population of bees and plenty of bees in the honey supers is considered normal. A large hive with few bees in the honey supers indicates a potentially collapsing colony. In those cases, we remove all of the honey supers and carefully examine the brood nest. Whenever we look into the brood nest, we are looking for evidence that we have a good, laying queen. The presence of eggs and young larvae indicates that there has been a queen in place in the past few days.

In the colony with the collapsing population of bees, we find eggs and larvae; but there is evidence that they are not the products of a good queen. Instead of the eggs being laid upright in the center of the cells, a number of eggs are laid on the sides of the cells. In a number of cells we find a number of eggs instead of a single egg. Click on Brandon’s photo to see cells with both a small c-shaped larva and extra eggs indicating multiple uses of the same cell over a number of days. Other cells show numbers of eggs laid in the same cell. This frame of brood appears to contain only non-fertile drone eggs and brood. There are two possible causes for drone laying. One is the presence of a worker bee with a fully developed reproductive system. The other potential cause is a queen bee that has depleted her supply of sperm and cannot fertilize eggs. In each case the colony is hopelessly doomed, as it cannot produce new workers or a new queen. A beekeeper must step in and take action or lose the colony. In each case the colony is unaware that it is collapsing because the laying worker and the sperm-depleted queen both secrete pheromones which stabilize the colony. See Brandon Dill’s powerful and imaginative work at: http://www.brandondillphotography.com/.
--Richard