Ecology of anthocorid (Hemipt.: Anthocoridae) predators of the pear psylla (Homopt.: Psyllidae) in the Okanagan Valley, British Columbia

G. J. Fields, B. P. Beirne


The supposition is not valid that the disappearance of the native <i>Anthocoris melanocerus</i> from pear orchards late in the summer is because of competitive displacement by the introduced <i>A. nemoralis</i>. It is because <i>A. melanocerus</i> migrates to where prey are most abundant whereas <i>A. nemoralis</i> remains on pear. <i>A. melanocerus</i> is concentrated on willows in the spring, moves to pear when <i>Psylla pyricola</i> becomes abundant, and moves to cottonwood when aphids on it become abundant and the numbers of <i>P. pyricola</i> on pear have become low.


Homoptera; Psyllidae; Hemipteral Anthocoridae

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