Department of Theoretical
Ecology
| |
Anders
Hedenström Ph D, Professor |
Royal Swedish Academy of Sciences Research Fellow
| |
Research
Interests and Projects |
Migration theory
Many animals living in a seasonal environment are migratory. What are the factors (ecological and evolutionary) giving rise to migratory behaviour and once a migrant, what are the best strategies by which to perform migration? Using optimality models the process of migration can be analysed and the best polices regarding fuel loads, stopover length, physiological and morphological adjustments to fuelling and flight, etc. When airborne, the bird should select the best timing for flight (night or day), the optimal flight speed, the best altitude with respect to wind, etc. Hence, the migration syndrome poses a multitude of problems that must be solved, ranging from habitat selection, physiological and behavioural adaptations. Over the years the analysis of these questions has resulted in a coherent migration theory. My research is concerned with this theory.
Animal aerodynamics
The principles of flapping flight are still not fully understood, especially in animals where the airfoils change shape and deform elastically during a wingbeat. In my lab we have developed new techniques to study freely flying animals. Most recently we enjoyed success with Digital Particle Imaging Velocimetry (DPIV) for visualising the wake vortices of birds across a wide range of speeds. These experiments are the first of their kind and were able to solve the long standing 'wake momentum paradox' by accurately characterizing the vortex topology and their aerodynamic properties. This approach is now being refined and developed, and ultimately the goal is to develop a new vortex theory for animal flight based on experimental vortex wake data. The next step is to use this theory for understanding morphological and behavioural adaptations to animal flight.
Migration and Behaviour
Hedenström, A.
& Alerstam, T. 1995. Optimal flight speed of birds. Phil. Trans. Roy.
Soc. Lond B 348, 471-487.
Hedenström, A.
& Alerstam, T. 1997. Optimum fuel loads in migratory birds: distinguishing
between time and energy minimization. J. theor. Biol. 189, 227-234.
Alerstam, T. & Hedenström,
A. 1998. The development of bird migration theory. J. Avian Biol. 29,
343-369.
Hedenström , A.
& Rosén, M. 2001. Predator versus prey: On aerial hunting and
escape strategies in birds. Behav. Ecol. 12, 150-156.
Hedenström, A.
2003. Optimal migration strategies in animals that run: a range equation
and its consequences. Animal Behaviour 66, 631-636.
Animal flight
Rosén, M. & Hedenström,
A. 2001. Gliding flight in a jackdaw: a wind tunnel study. J. Exp.
Biol. 204, 1153-1166.
Hedenström, A.
2002.Aerodynamics, evolution and ecology of bird flight. Trends.
Ecology & Evolution 17, 415-422.
Spedding, G. R., , Rosén,
M., Hedenström, A. 2003. A family of vortex wakes generated
by a thrush nightingale in free flight in a wind tunnel over its entire
natural range of flight speeds. J. Exp. Biol. 206, 2313-2344.
Rosén, M., Spedding, G. R., Hedenström, A. 2004. The relationship between wingbeat kinematics and vortex wake of a thrush nightingale. J. Exp. Biol. 207, 4255-4268.
Hedenström, A., Rosén, M. & Spedding, G. R. 2006. Vortex wakes generated by robins Erithacus rubecula during free flight in a wind tunnel. J. R. Soc. Interface 3, 263-276.
Lecturing mainly at the 10
credit courses in Theoretical Ecology, Evolutionary Animal Ecology
and Ornithology.
Supervising PhD students
and 20 credit honours thesis
Address: Theoretical Ecology,
Ecology Building, 223 62 Lund , Sweden
Phone: +46 (0)46 2224142,
Fax: +46 (0)46 222
Publisher: Anders Hedenstrom
E-mail: anders.hedenstrom@teorekol.lu.se
|