Table 1.

Summary table of all the measured forces generated by northern flying squirrels during leaping and landing

Take-off force (bw) Landing force (bw)
Squirrel IDWing span (cm)Wing area (cm2)Leap distance (m)Mass on day of testing (g)CountMean ± s.d.CountMean ± s.d.
YF128.05110.527293.70±1.99--
127464.64±1.1763.47±0.37
1.5267104.36±1.64104.88±0.35
2256.5*75.57±1.5377.58±0.96
2.5256.5*55.91±1.4956.16±0.54
YF227.55000.520082.56±1.28--
1201105.21±2.47103.56±0.30
1.5198113.30±1.70114.28±0.21
YM25.95540.525993.38±0.96--
126046.97±1.2343.79±0.44
  • YF, young female; YM, young male; bw, body weight.

    There are 79 take-offs but only 53 corresponding landings because no landing force data was obtained for the shortest range jumps of 0.5 m. Only one individual, YF1, performed in the barn but it would not land on the force pole at distances greater than 2.5 m. Unfortunately, for reasons beyond our control, YF2 only cooperated at 0.5, 1 and 1.5 m and YM at 0.5 and 1 m.

  • * Squirrels seemed to lose a considerable percentage of their weight before testing at this distance. The reason for this is unknown but it could have been caused by the change of environment as these tests were carried out in a barn, which was very hot and humid compared to the temperature-controlled lab.