Economic Importance for Humans: Positive
Eurasian jays are important in the regeneration of oak forests through acorn dispersal. Oaks are important to people because of their wood, beauty, and ability to enhance biodiversity. One study from a park in Sweden estimated how much money it would cost for humans to do the same job as Eurasian jays. The researchers determined it would cost between 1 and 6 million kroners (about 125,000 to 751,000 U.S. dollars) to replace Eurasian jays with people planting acorns in the 2700 hectare park.
A study in Germany found oaks regenerated in pine forests at a rate of 2,000 to 4,000 trees per hectare. Since mother oak trees were largely unavailable, they attributed this regeneration to Eurasian jays. The area was clearcut about 30 years before the study was performed and mostly pines regenerated. Oak trees were not recruited into the regenerating forest until Eurasian jays moved into the pine forest and began caching acorns.