Assertion: abalone | /r/HasProperty | harvested by native americans
Facets:
value: for at least 12,000 years
type: TEMPORAL
Source sentences:
text: On the Channel Islands, where abalones were harvested by Native Americans for at least 12,000 years, the size of red abalone shells found in middens declines significantly after about 4000 years ago, probably due to human predation.[citation needed]