The Dutch group Sportvisserij Nederland plans to use recordings of calling killer whales (orcas) to drive away cormorants from some bodies of water. This unique method of bird deterrence, a French concept, will begin a trial run soon in Limburg.
Klotputten by Jos Dielis, Creative Commons on Flickr
Cormorants have no natural enemies in the Netherlands and in recent years their population has boomed. In the last 25 years the number of birds has increased twenty-fold. Management of the cormorants across Europe has been a hot issue for many years, especially for fish management.
High concentrations of cormorant nests are known to kill trees and ruin habitat for other water birds like herons. During several guided birding excursions in Holland, we saw the destruction caused by cormorant invasions and heard of the issues the wildlife managers faced.