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Table 1 Summary of GLMMs run for different species modeling ground speed as a function of wind support (w s ), cross wind (w c ) and their interaction term (w s * w c ), using the three methods to determine ground speed and flight direction (instantaneous, next location and next location + 2 km) described in the text.

From: Flying with the wind: scale dependency of speed and direction measurements in modelling wind support in avian flight

Species Median airspeed   w s w c w s * w c Adj. R2 Intercept ± SE N
Anas platyrhynchos 15.86 Instantaneous *** * NS 0.15 12.63±0.58 1293
   Next location * NS NS 0.02 5.65±0.22 418
   Next location + 2 km Error * NS NS <0.01 4.61±0.04 1762
Anser albifrons 15.98 Instantaneous *** NS NS 0.45 14.91±0.6 151
   Next location NS NS NS 0.23 11.43±1.3 78
   Next location + 2 km Error NS NS NS 0.23 11.36±1.29 78
Branta leucopsis 15.83 Instantaneous *** ** * 0.52 14.77±0.23 1124
   Next location *** NS NS 0.26 10.66±0.41 661
   Next location + 2 km Error *** NS NS 0.26 10.62±0.41 659
Ciconia ciconia 13.01 Instantaneous *** * NS 0.35 12.98±0.19 1534
   Next location *** NS NS 0.22 7.24±0.32 972
   Next location + 2 km Error *** NS NS 0.23 7.32±0.25 971
Creagrus furcatus 9.69 Instantaneous *** *** NS 0.49 8.69±0.15 2001
   Next location *** *** NS 0.30 7.23±0.13 1632
   Next location + 2 km Error NS NS ** <0.01 7.68±0.46 4769
Cygnus cygnus 16.71 Instantaneous *** *** NS 0.56 16.42±0.21 997
   Next location *** NS NS 0.16 10.38±0.40 864
   Next location + 2 km Error *** NS NS 0.16 10.31±0.40 867
Larus scoresbii 12.59 Instantaneous ** NS NS 0.31 10.80±0.64 190
   Next location NS NS NS 0.03 5.12±0.36 75
   Next location + 2 km Error NS NS NS 0.03 5.00±0.29 84
Phoebastria irrorata 13.30 Instantaneous *** *** NS 0.66 12.45±0.18 2081
   Next location * * * 0.11 5.90±0.16 1500
   Next location + 2 km Error * * * 0.10 6.02±0.16 1519
Tadorna ferruginea 14.94 Instantaneous *** * NS 0.10 14.11±0.17 1250
   Next location NS NS NS <0.01 8.22±-0.45 464
   Next location + 2 km Error NS NS NS <0.01 8.32±-0.47 462
  1. ***= p<0.0001, **= p<0.001, *= p<0.05. N is the number of observations used in the models. SE is standard error of the estimate. Median airspeeds were estimated using instantaneous ground speed measurements and ECMWF data (see also Figure1) with vector addition, whereas the intercept represents an estimate of airspeed using the regressive model under no wind condition ( wsand wc= 0). In both cases a minimum ground speed of 4m/ s was used to filter locations that could have been stationary animals.