Table 1.

Summary of two-way interaction least-squares linear model predicting slope of α across 19 weather surveillance stations during spring and autumn migratory periods.

parameter	estimate	s.e.	t-value	P (>|t|)
spring
intercept	1.775	0.376	4.718	0.000275
latitude	−0.0310	0.00951	−3.262	0.00525
distance to coastline (km)	−0.00640	0.00247	−2.594	0.0203
latitude: distance to coastline (km)	0.000130	0.0000590	2.199	0.0440
autumn
intercept	−0.556	0.537	−1.035	0.317
latitude	0.0192	0.0136	1.416	0.177
distance to coastline (km)	0.00271	0.00352	0.771	0.453
latitude: distance to coastline (km)	0.0000510	0.0000840	−0.607	0.553