Crows hold grudges against individual humans, often attacking, for up to 17 years
The research project, led by experts at the University of Washington, was launched in 2006.
Professor John Marzluff, an environmental scientist, initiated the study by donning a fearsome mask and temporarily trapping seven crows. He identified them with leg rings before their safe release.
In subsequent years, the professor and his assistants sporadically wore the same mask — strolling the university campus while feeding the resident crows.
Marzluff recalled an incident while wearing the mask when 47 out of 53 crows he encountered vehemently scolded him.
This was a substantial increase from the original seven crows that were captured, suggesting that these birds could recognize threatening humans and pass on this knowledge to their kin.
The climax of this fascinating study came in 2013 when the number of aggressive caws reached their peak, only to gradually decrease.
By September 2023 — 17 years since the experiment began — not a single scolding crow was heard on one of Marzluff’s masked walks.
Another intriguing facet of the study involved the use of a “neutral” mask, bearing the likeness of Dick Cheney, who was the vice president of the United States at the time.
Those sporting the Cheney mask fed the crows without causing them any distress, and were subsequently spared of avian wrath.
As the research progressed, unknowing volunteers were roped in to wearing the masks, ignorant of the “dangerous” or “neutral” categorization by the crows.
One such volunteer found himself at the center of an avian uproar, confirming the crows’ skill in discerning and remembering threats.
- Eric Ralls, earth.com (12.11.24)