APIS Volume 4, Number 8, August 1986
In this issue
- Florida Bee Botany Published
- More Concerning Stress on Colonies
FLORIDA BEE BOTANY
One of the unique parts of Florida beekeeping is the array of plants used by honey bees to gather nectar and pollen. Some are the same as found elsewhere in the United States, but many are not. In addition, most honey and pollen plants important to bees are wild or feral and not cultivated, citrus being the one exception. This means descriptions are not always available to the lay person.
A Florida Beekeeping Almanac, Florida Cooperative Extension Circular 537 provides a listing of plants important to bees. Through the use of a calendar, beekeepers and others can calculate what plants will bloom, when and where. Although this is valuable information, there have been numerous requests to publish a Circular specifically describing plants important to honey bees in Florida.
The task has finally been accomplished. Florida Cooperative Extension Circular 686, Florida Bee Botany, is now available. It is new and many extension offices may not have it on the shelf, but can make requests through the IFAS publications office. The job has not been easy for a number of reasons.
It took myself, a consulting botanist, a professional artist (also an amateur botanist) and a most dedicated editor a great deal of time and energy to publish the circular. This effort has already been rewarded to some degree; the publication has been nominated for an designer's award. It is our hope this will not only be useful to those interested in bee plants, but also delight the aesthetic sensibilities of those who might casually page through it.
[Editor's Note 5/12/1997--This publication is still in print and a few last copies are available; like many others, however, it will metamorphose to other formats, including CD ROM and the world wide web.]
STRESS ON BEE COLONIES
"Stress is often cited as the cause of many bee problems, especially those of disease but also for other maladies or nonproduction situations." This quote is from an article in a past issue of the New Jersey Beekeepers Association News, written by Dr. Michael Burgett, Oregon State University. I believe the influence of various kinds of stress on a colony are often ignored and pleaded (see June 1984 APIS) for beekeepers to reduce it to a minimum in their management. The following remarks are paraphrased from Dr. Burgett's article:
Stress doesn't cause a particular disease, but weakens a colony so that disease might get a foothold. A bee colony should be looked at as a "black box," into which energy (pollen, nectar, water) flows and is then converted into products (honey, beeswax, brood, bees). Anything reducing energy flow into the box is termed stress. The beekeeper is interested in removing as much energy from the system (honey, wax or pollination in the form of worker bee energy) as possible. Paradoxically, therefore, the beekeeper becomes a component of stress on a colony.
Weather is perhaps the greatest potential source of colony stress. Inclement conditions slow down or stop altogether flow of nectar and pollen into a colony. In spring and early summer, the brood is consuming large amounts of energy (food). A sudden shut down of foraging (rainy conditions, confinement by the beekeeper for moving), if prolonged, causes severe stress. The bees' solution is to stop brood rearing, reducing energy investment and colony growth. Good management provides food during this stress period.
Water supply is critical. During dry periods, more energy is required to forage for water (longer distances, more trips). Nurse bees require water to produce jelly and dilute honey. Combs might also melt in extremely hot weather in spite of efforts by fanning adults, if water is not available. A beekeeper can reduce stress by providing water for bees in dry times (See May 1986 APIS). In cold weather, moisture must be ventilated or it can cause stress on the cluster which is attempting to keep the brood warm.
Temperature fluctuation also causes stress. The brood nest temperature needs to be maintained (93-95 degrees F.) for normal brood development. Anything interfering with temperature control (colonies located in cold locations or in damp conditions) causes more energy (more bee work fueled by pollen and nectar) to be funneled into heat production. Chilled brood is an excellent example of stress on a colony. Too much brood for the available population to cover results in individuals on the outside of the brood nest to die. More energy is required to produce replacement individuals and energy is also required to remove the dead larvae or pupae.
Any phenomena interfering with internal efficiency is termed stress. Some of the more important factors are: number of adult bees, ratio of adult bees to brood and egg laying rate of the queen. All these go into determination of the energy necessary to operate the colony. Because larvae are provisionally fed (a little at a time as needed), there must be a population of young bees in proportion to larvae requiring feeding. The queen's egg- laying rate is regulated to allow for this constantly changing ratio by the colony. Other adults must also be available to provide nectar and pollen required by the nurses (which usually don't forage) to feed the larvae. Two conditions that can radically change a population balance are swarming and pesticide poisoning. Beekeeper-caused conditions include making a split or shaking a package to make increase.
The best general rule to avoid stress is maintain at all times a strong colony of bees, concludes Dr. Burgett. Strong hives translate into "black boxes" capable of dealing better with environmental fluctuation. They can also more quickly change bee ratios for efficient colony operation.
To all of the above I add a hearty amen. As I wrote back in 1984:
All this is not to make an already complex subject less understandable. Rather it is to plead for more concise observation and clearer thinking when developing conclusions and/or contemplating solutions to declines in colony productivity. The successful beekeeper is one who knows when to let the bees alone, yet actively helps them through stressful times to attain their maximum productivity (energy output).
Sincerely,
Malcolm T. Sanford
Bldg 970, Box 110620
University of Florida
Gainesville, FL 32611-0620
Phone (352) 392-1801, Ext. 143 FAX: (352)-392-0190
http://www.ifas.ufl.edu/~mts/apishtm/apis.htm
INTERNET Address: MTS@GNV.IFAS.UFL.EDU
©1986 M.T. Sanford "All Rights Reserved
