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Providing evidence to improve practice

Individual study: The use of distress calls to repel night herons Nycticorax nycticorax from fish ponds at Kibbutz Dan in the Hula Valley, Israel

Published source details

Spanier E. (1980) The use of distress calls to repel night herons (Nycticorax nycticorax) from fish ponds. Journal of Applied Ecology, 17, 287-294

This study is summarised as evidence for the intervention(s) shown on the right. The icon shows which synopsis it is relevant to.

Scare birds from fish farms Bird Conservation

A controlled trial in northern Israel in September and October 1978 (Spanier 1980) found that 88% (1,122 of 1,265) of black-crowned night-herons Nycticorax nycticorax feeding at fishpond were scared off when heron distress calls (both adult and juvenile) were played on 12 observation nights. Over the study period there was no apparent habituation to the distress calls, in contrast to when recordings of a gas gun were used, when herons became habituated after only one night (60% of birds remained at ponds after 12 nights). Distress calls also reduced the number of herons perched in nearby trees by approximately 50% and, despite less than 5% of scared herons leaving the area, the scaring significantly reduced fish losses over the study period.