SIERDSMA H (1989) Short contributions: Influx of Red-footed Falcons Falco vespertinus in spring 1988. LIMOSA 62 (3): 155-157.

Red-footed Falcon Falco vespertinus In spring 1988, unusual numbers of Red-footed Falcons were seen in the Netherlands, partly due to strong easterly winds during May. Approximately 215 different birds, of which 65 migrating, were seen. In the coastal provinces peak numbers were recorded in the period 14-16 May, inland numbers showed a peak in the period 21- 23 May (fig. I). The falcons preferred dunes and heathland as resting place (fig. 2). The distribution over the sexes and ages was: immature males 24%, immature females 29%, adult males 20% and adult females 27% (n = 79). The flock size of resting birds varied between 1 and II birds, the average flock size was 2.3 and 27% was solitary. The average flock size of migrating birds was 1.5 (47% single birds). Mean flight direction of migrating birds was NE, of birds flying inland on average ENE

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