FILENAME:  MAYAPIS.93
 
            Florida Extension Beekeeping Newsletter
    Apis--Apicultural Information and Issues (ISSN 0889-3764)
                  Volume 11, Number 5, May 1993
 
                    RESTRICTIONS ON THE RISE?
 
     Two disturbing bits of news recently came my way.  As reported
in the Tara Beekeepers Newsletter, south Metro Atlanta, Gwinnett
County recently upheld its ordinance restricting beekeeping to
agriculturally zoned areas.  This happened despite attempts by Dr.
Keith Delaplane of the University of Georgia and others who met
with the County Planning Commission to explain why this wasn't
necessarily a good idea.  The Commission was given a copy of the
Texas Model City Beekeeping Ordinance, and several arguments for
keeping bees in urban areas were advanced, including the fact that
this would limit competition from wild colonies of African bees.
The decision to ignore the advice and evidence was unanimous.
 
     I also received a call from a lawyer hired by a local planning
commission in Florida to help with a case brought by a beekeeper.
The beekeeper is suing for "unreasonable" restrictions which are
adversely affecting his occupation.  The powers that be are now
enforcing an old ordinance restricting beekeeping altogether in the
community, depriving the beekeeper of income.  The history appears
to be one where urbanites have moved into an area where the
beekeeper had been operating for a long time.  The lawyer wanted an
expert witness who would explain to the court why such an ordinance
was appropriate.  He didn't find one here.  But that isn't stopping
him from arguing to uphold the restriction.
 
     There will undoubtedly be more of these kinds of scenarios in
the future.   Beekeepers must be prepared at any moment to go
before county commissions or judges and plead a case for the
continuation of beekeeping in both urban and rural areas.  As an
aid to those who find themselves in this situation, I have
published ENY 115, Good Neighbor Guidelines and Ordinances.  It
should be available from any County Extension Office via the
Gainesville VAX or IFAS CD-ROM Disk 7.  I will mail out a copy on
request as well.
 
                       SEQUENTIAL SAMPLING
 
     As I pointed out last month, the tracheal mite problem
continues to vex beekeepers.  It is expensive to treat bee colonies
with chemicals to control mites; such applications are not always
effective and their use hinders the search for genetic resistance.
For these and other reasons, chemicals should be applied only when
a certain infestation level is reached.  Unfortunately, a uniform
procedure has yet to be developed to determine treatable levels.
 
     Into this fray come several investigators at Pennsylvania
State University.  They have published a detailed bulletin (#871)
entitled "A Sequential Sampling Scheme for Detecting the Presence
of Tracheal Mite (Acarapis woodi) Infestations in Honey Bee (Apis
mellifera L.)."  This publication, according to the authors, gives
information on how to classify tracheal mite infestation levels in
individual colonies resulting in considerable savings in time,
labor and expense.  It is available free from Maryann Tomasko,
Department of Entomology, Penn State University, 501 ASI Bldg.,
University Park, PA 16802, ph 814/865-4621.
 
                         FOCUS ON VARROA
 
     Volume sixteen of Experimental and Applied Acarology (No. 4),
December 15, 1992 is a full issue devoted to the Varroa bee mite.
In an effort to distribute the latest information on the biology of
this dangerous bee parasite, the editor, Dr. J. Beetsma, has
compiled this special volume.
 
     A group of Italian investigators reported how quickly colonies
treated for Varroa can be reinfested.  This confirms thoughts I
expressed in the March APIS that these mites are really a beekeeper
community problem.  In "Reinfestation of an Acaricide-Treated
Apiary by Varroa jacobsoni Oud.," the authors detail experiments
showing a small reinfestation in the spring, rising dramatically in
the fall when nectar was scarce.  Drone excluders did not limit
mite importation into the colony and it appeared that robbing
infested colonies was a prime source of mites.
 
     The conclusions of the study are: (1) treatments should be
carried out at the same time in all colonies by all beekeepers in
a given area; (2) treatments should not be carried out too early,
since risk of reinfestation is maximal in the end of the season;
(3) products with long-lasting action could be introduced twice,
thirty days at the end of summer (so unparasitized winter bees
develop) and for fifteen days before bees cease activity for the
winter; (4) since feral colonies are perhaps the main source of
reinfestation, effective swarm control would be a useful technique
to reduce reinfestation.  In a caveat at the end, the authors
suggest reinfestation rates should be examined in other geographic
areas.
 
     In "Lack of Allozyme Variability Among Varroa Mite
Populations," A. Biasiolo, also from Italy, found that mites from
different parts of the world were very similar in genetic makeup
and there was little evidence that different species exist.
However, the paper suggested this might be the result of
introductions of the same population over the globe.   Samples
collected only in Europe and China were compared.  Mention is made
that South American mites are somewhat, though not very, different.
The author also suggests the variability might be small because of
the mite's closed breeding system within the bee colony.
 
     A group of investigators from the Netherlands reported the
number of mites found in worker versus drone cells.  In
"Differential Periods of Varroa Mite Invasion into Worker and Drone
Cells of Honey Bees" the mites' apparent preference for drone brood
was reconfirmed, but, the authors conclude, other mechanisms may be
determining whether mites invade drone or worker cells.  Mites
invaded cells only when the larva covered the cell bottom and the
more worker brood cells present, the higher the rate of invasion.
 
     In "Observations on the Initiation and Stimulation of
Oviposition of the Varroa mite," authors from the Netherlands found
that in order to successfully lay eggs, females need access to
adult bees.  Neither contact with juvenile hormone nor larval food
provoked egg laying.
 
     German researchers in "Grooming Behaviour of Apis cerana, Apis
mellifera and Apis dorsata and its Effect on the Parasitic Mites
Varroa jacobsoni and Tropilaelaps clarea" reconfirmed conclusions
from other studies that cerana worker bees have a more intensive
and effective grooming response for Varroa mites.  However, these
researchers were unable to replicate full grooming by cerana on
mellifera workers as reported in other research.  In addition, the
effect of the grooming by mellifera was only to remove mites, not
to catch and destroy them.
 
     There is a body of evidence suggesting adult mellifera worker
bees uncap and remove mite-infested larvae.  Two German researchers
in "The Removal Response of Apis mellifera L. Colonies to Brood in
Wax and Plastic Cells After Artificial and Natural Infestation with
Varroa jacobsoni Oud. and to Freeze-killed Brood," attempted to
find the specific signals by which bees detect affected larvae.
They were unable to do so, but did show that there was better
infested larval removal from plastic comb ("Jenter"- and ANP-Comb)
than from wax comb.  They also compared removal of freeze-killed
brood with that of Varroa infested brood and found a positive
correlation, indicating that the standard test for "hygienic
behavior" using freeze-killed brood could also be used to measure
mite resistance.
 
     Researchers at the University of Florida reported a comparison
of honey bee and mite skins (cuticles).  In "Cuticular Hydrocarbons
from Varroa jacsobsoni," evidence was found that mites appear to
mimic the individual bee they are on.  Thus, mites found on worker
pupae had the same skin makeup as the pupae; those found on adult
workers and drones which are different from each other also "looked
like" their hosts.  The authors speculate that one reason for this
is to prevent bees from detecting mites, in essence helping them
become integrated into honey bee colony life.
 
     Drones could be a key to breeding for Varroa resistance,
according to German authors of "Selection of Resistance Against
Varroa jacobsoni Across Caste and Sex in the Honeybee (Apis
mellifera L.,  Hymenoptera: Apidae)."  Because honey bees with a
short post-capping stage (faster larval development) are partially
resistant to Varroa and drones have large variation in this trait,
selecting for rapidly-developing drones is possible.  Using drones
would also avoid some usual selection problems encountered in honey
bees.  Another generation of workers would not have to be reared to
see if the short post capping trait actually shows up as is
necessary when selecting queens.
 
                          QUALITY HONEY
 
     Securing the best quality and quantity honey possible is the
goal of every honey producer.  The field is not without ideas and
filled with some controversy.  Major considerations have been when
to remove honey from the colony and management technique to ensure
the bees make the most and best sweet possible.  In a recent
article, "Effects of Frequency of Honey Removal and Empty Comb
Space on Honey Quantity and Quality," Bee Science, Vol. 2, No. 4,
pp. 187-192, a Canadian team led by Dr. Tibor Szabo examined
several scenarios based on previous statements in the literature.
The authors specifically examined differing views about whether
frequent honey removal increases/decreases final production, the
amount of honey that should be capped before removal and the
concept that more empty comb space stimulates final production.
 
     Thirty-six overwintered colonies were used in the study; 18
had one-year-old queens, the others were headed by two-year-olds.
Three honey removal treatments (four, two, and one times) and three
regimes of supering (adding five, ten and 11-15 supers!).  In total
nine treatments were replicated four times.  During the honey flow,
the "abandon method" was used.  Supers were simply taken off and
stacked on end; the bees abandoned them and no robbing was
apparent.  At the end of the flow, a bee blower was used.  All
supers were individually weighed to determine production and three
combs of honey per colony were taken at random to determine quality
based on diastase number and moisture content.
 
     The results of the study indicated that frequency of honey
removal and age of the queen significantly influenced production.
Colonies with two honey removals produced more honey (312.6 lb)
than those with either one or four removals (233.2 and 255.6 lb,
respectively).  Colonies with one-year-old queens yielded more
honey (309.7 lb) than those headed by two-year-old queens (224.6
lb).  The number of empty supers applied had little influence on
honey production.
 
     When honey was taken off four times, there was little if any
of the comb capped.  About half the cells were capped with two
removals; all was capped with one removal.  Moisture content was
significantly affected by the number of supers provided and the
frequency of honey removal.  It was highest in colonies with five
supers and four honey removals (19.0%); lowest with 12 supers and
two removals (16.7%).  The highest diastase numbers as expected,
were for single honey removal; the lowest with four removals.
 
     The authors conclude that too frequent honey removal decreases
quality.  Moisture content was acceptable with two removals, but
not with four.  In addition, extra comb space is needed to ripen
the crop adequately.  Although honey can be "artificially" dried in
hot rooms, the authors contend that quality is diminished because
enzyme count is low and there is an increase in
hydroxymethylfurfural (HMF).  The latter number is routinely
considered an indication of how much honey is heated and therefore
degraded.
 
     Where moisture content is a problem in temperate and
subtropical areas, the authors recommend adding more supers than
normal (perhaps six to seven, for example, instead of five) and
removing honey twice for maximum quality and quantity.  Finally,
they discuss the importance of a young queen, but are not
necessarily in agreement, in spite of their results, that one-year-
olds are far more productive than two-year-olds.
 
     Two fact sheets available from this office address in detail
quality, standards and moisture in honey.  They are Hint for the
Hive #129, "Honey Judging and Standards," and Hint for the Hive
#130, "Moisture in Honey."
 
                    APIMONDIA MEETS IN CHINA
 
     The 33rd International Apicultural Congress is scheduled to
meet in Beijing, China September 20-26, 1993.  I am in receipt of
the second circular which contains all the details.  The theme is
the honey bee and human health.  For thousands of years, Chinese
medicine has used various forms of natural therapies to treat
diseases.  It seems only natural, therefore, that apitherapy should
be the focus of this meeting.  If you would like more information
on this conference, contact me for a registration form.
 
     Several tours are being offered as part of the Apimondia
meeting.  Perhaps most relevant, however, is the chance to travel
with this country's best known apitherapist, Mr. Charles Mraz.  He
and colleagues of the American Apitherapy Society, Inc. are
planning a trip through the Citizen Ambassador Program which is
scheduled to visit Chinese clinics and physicians practicing
apitherapy, as well as Dr. Fang Zhu's International Conference on
Apitherapy, Bee-Acupuncture and Healthcare in Nanjing.  The trip is
scheduled from September 19 through October 2.  For details,
contact Mr. Michael Rennaker, phone 509/534-0430.
 
Sincerely,
 
 
 
Malcolm T. Sanford
Bldg 970, Box 110620
University of Florida
Gainesville, FL 32611-0620
Phone (904) 392-1801, Ext. 143
FAX: 904-392-0190
BITNET Address: MTS@IFASGNV
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