|
|
|
|||
| Home Help Feedback Subscriptions Archive Search Table of Contents | ||||
First published online March 14, 2005
Journal of Experimental Biology 208, 1161-1173 (2005)
Published by The Company of Biologists 2005
doi: 10.1242/jeb.01510
Honeybee flight metabolic rate: does it depend upon air temperature?
1 Department of Biology, University of Massachusetts Boston, Boston,
Massachusetts 02125-3393, USA
2 Department of Biology, University of Vermont, Burlington, Vermont 05405,
USA
* Author for correspondence (e-mail: woody.woods{at}umb.edu)
Accepted 24 January 2005
Differing conclusions have been reached as to how or whether varying heat production has a thermoregulatory function in flying honeybees Apis mellifera. We investigated the effects of air temperature on flight metabolic rate, water loss, wingbeat frequency, body segment temperatures and behavior of honeybees flying in transparent containment outdoors. For periods of voluntary, uninterrupted, self-sustaining flight, metabolic rate was independent of air temperature between 19 and 37°C. Thorax temperatures (Tth) were very stable, with a slope of thorax temperature on air temperature of 0.18. Evaporative heat loss increased from 51 mW g-1 at 25°C to 158 mW g-1 at 37°C and appeared to account for head and abdomen temperature excess falling sharply over the same air temperature range. As air temperature increased from 19 to 37°C, wingbeat frequency showed a slight but significant increase, and metabolic expenditure per wingbeat showed a corresponding slight but significant decrease. Bees spent an average of 52% of the measurement period in flight, with 19 of 78 bees sustaining uninterrupted voluntary flight for periods of >1 min. The fraction of time spent flying declined as air temperature increased. As the fraction of time spent flying decreased, the slope of metabolic rate on air temperature became more steeply negative, and was significant for bees flying less than 80% of the time. In a separate experiment, there was a significant inverse relationship of metabolic rate and air temperature for bees requiring frequent or constant agitation to remain airborne, but no dependence for bees that flew with little or no agitation; bees were less likely to require agitation during outdoor than indoor measurements. A recent hypothesis explaining differences between studies in the slope of flight metabolic rate on air temperature in terms of differences in metabolic capacity and thorax temperature is supported for honeybees in voluntary flight, but not under agitation.
Key words: Apis mellifera, thermoregulation, flight energetics, water loss, wingbeat frequency, bee
![]()
CiteULike
Complore
Connotea
Del.icio.us
Digg
Reddit
Technorati
Twitter What's this?
This article has been cited by other articles:
![]() |
K. S. Mapalad, D. Leu, and J. C. Nieh Bumble bees heat up for high quality pollen J. Exp. Biol., July 15, 2008; 211(14): 2239 - 2242. [Abstract] [Full Text] [PDF] |
||||
![]() |
J. C. Nieh and D. Sanchez Effect of food quality, distance and height on thoracic temperature in the stingless bee Melipona panamica J. Exp. Biol., October 15, 2005; 208(20): 3933 - 3943. [Abstract] [Full Text] [PDF] |
||||