Wednesday 8 March 2017

Grass-pulling behaviour in gulls



One of three Herring Gulls (above) on the croft this morning demonstrating grass-pulling behavior. 
As per Nikolaas Tinbergen, ethologist and Nobel Prize winner: "... (this) occurs typically when two male birds meet on the boundary of their territories, as new birds are settling in. One or both of the birds may tear lumps of grass or moss from the ground with their bills. Grass-pulling Tinbergen concluded, was the result of a conflict between the desire to fight and the desire to flee. Each birds thwarted urges were 'displaced' into a new activity: Each in collecting nest material , it is true, but each is really doing to the grass what he would do to his opponent if he dared to get hold of it." 
(New York Times, 7 April, 1974)




(New York Times, 7 April, 1974)

No comments:

Post a Comment