F. Eischen, R. Graham, R. Rivera (USDA Bee Lab, Weslaco, TX) and J. Traynor (CA

From Fall 2006 Magazine of American Honey Producers Association (AHPA)

In 2005 about 5000 Australian packages of honey bees were air freighted to California for almond pollination.  They were sufficiently interesting that during 2006 about 30,000 packages of these bees were imported.  We compared the pollen collecting behavior of these package colonies with US colonies during 10 February – 2 March 2006.  Both Australian and US colonies (60 trapped and 30 free-flying) foraged normally and we saw little difference in foraging time, i.e. time of day.  Major differences were observed in the amount of pollen collected.  Standard “8-frame” US colonies collected, on average, 112.7 grams per day, which was a little more than twice that collected by 4—lb Australian colonies which brought in 48.7 grams.  Six-frame US colonies and 3-lb Australian colonies collected 37.8 and 22.2 grams respectively.  These differences mostly reflect colony strength and broodnest size.  Our “8-frame” colonies were really 10-frame colonies using the traditional counting method.  That wasn’t by design it just happened, but having that size colony was not out of line with the average colony brought to almond pollination.  In 2005, we conducted a survey of 955 colonies pollinating almonds that were randomly chosen from 46 beekeepers.  Their average was 9.0 frames of bees.  This included all colonies, even some deadouts which counted as zeros.  So our standard colony was not too far off the average.  The 4-lb Australian colonies, had on average, 5.6 frames of bees using the California count.  Six-frame US and 3-lb Australian colonies had 5.6 and 3.3 frames of bees, respectively.  Across the board, we had good positive correlations between colony strength and pollen collected.  So by and large, bigger colonies collected more pollen.  As expected, our package colonies which were made up in late January, lost strength during almond pollination.  To get an accurate count of this, we measured strength (adult bees covering the comb) in tenths of a Langstroth frame at the beginning (8 Feb) and end (3 Mar) of the test.  Three-pound and 4-lb Australian package colonies lost 0.3 and 0.6 frames of bees, respectively.  US 8-frame and 6-frame colonies gained 1.6 and 3.2 frames of bees during the same time.

It’s a given that larger colonies are generally better than small ones, but we were also interested in the effort Australian bees made on an individual basis.  To get at this, we asked the question, how much pollen did colonies collect per frame of bees.  This is simply the weight of pollen collected divided by the frames of bees in a colony.  We did this for both starting and ending strengths.  Things got interesting here (scientifically speaking) in that the US 8-frame colonies based on starting strength, collected nearly 20 grams of pollen per frame of bees while the Australian 4-lb colonies collected close to 13 grams per frame.  Using ending strengths, however, 8-frame US colonies collected 12.7 grams of pollen per frame and the 4-lb Australian colonies 14.8 grams per frame of bees.  In other words, by the end of the trial, Australian colonies were collecting slightly more pollen per frame of bees than did the US 9-frame colonies (the US 6-frame and 3-lb colonies showed the same reversal when comparing beginning and ending bee populations).  We don’t know the cause for this, but suspect that the package colonies built a large broodnest but lost adult strength.  This caused surviving foragers to receive increased stimulus to forage, i.e., for a while, they collected more pollen on a per bee basis.

In summary, our data indicate that the 4-lb Australian package colonies performed about like the 6-frame US colonies, and collected a little less than half the pollen collected y the “8-frame” US colonies.  The 3-lb Australian package colonies collected about half the pollen that the 4-lb package colonies collected.