Abstract:
Colonies of Apis florea, which only abscond a short distance, usually return to salvage old nest
wax; but, those colonies, and all other honeybee species which go considerably further, do not.
Wax salvage would clearly be counter-productive unless the energy input/energy yield threshold
was a profitable one. There are two possible trade-offs in this scenario, the trade-off between the
energy expended to recover the wax (recovering hypothesis) as against that of replacing the wax
by new secretion (replacing hypothesis). In order to compare the two hypotheses, the fuel costs
involved in salvaging wax on one return trip, the average flower handling time, flight time and
relative values for substituting the salvaged wax with nectar were calculated. Moreover, the
energy value of the wax was determined. Net energy gains for salvaged wax were calculated.
The energy value of the salvaged wax was 42.7 J/mg, thus too high to be the limiting factor since
salvaging costs are only 642.76 mJ/mg (recovering hypothesis). The recovery costs
(642.76 mJ/mg) only fall below the replacement costs for absconding distance below 115 m thus
supporting the replacing hypothesis. This energetic trade-off between replacing and recycling
plus the small absconding range of A. florea might explain why A. florea is probably the only
honeybee species known to salvage wax and it parsimoniously explains the underlying reasons
why A. florea only salvages wax from the old nest if the new nesting site is less than 100–200 m
away—energetically, it pays off to recycle.
Electronic supplementary material The online version of this article (doi:10.1007/s00360-010-
0530-6) contains supplementary material, which is available to authorized users.
