RENSSEN TA (1991) Keepin up: Invasion Common Common Crossbill Loxia curvirostra 1990. LIMOSA 64 (1): 29-30.

Whom the call of flying crossbills in recent months has not heard, has been out much. Yond there because a substantial invasion site. During June reported tensile counters of the National Bird migration Counting Working Group (LWVT) in both the inland and coastal above average numbers Cross-long linear basin. During July the swelled power on, am on the transition from a July-August to peak (Figure I). Then the weakness influx temporarily, but late September-early October was re-peak periods. At that time could crossbills dead tired on the islands of shrubs be picked. Just as they foraged in August not aileen on cones of pine and spruce, but oak at rose hips, berries and flour thrush isl beech nuts. after beginning October, the tensile strength rapidly.

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