Assertion: great auk | /r/CapableOf | fill unique niches
Facets:
value: to the midwestern plains
type: LOCATION
Source sentences:
text: The Great Auk, Labrador Duck, Passenger Pigeon, Carolina Parakeet, and Heath Hen were birds that once filled unique niches in the North American landscape from the shores of Labrador and New York to the Midwestern plains.