Assertion: owl's population | /r/HasProperty | increased by researcher
Facets:
value: artificially
type: MANNER
Source sentences:
text: When a population of great (Parus major) and Eurasian blue tits (Cyanistes caeruleus) was artificially increased by researchers in the vicinity of tawny owl nests, it was found that, despite the tits not being common food, the owls did reduce the population of increased tit.