FILE PHOTO: Barred owl (BryanHanson/Morguefile license https://morguefile.com/license
"Spotted owls are inclined to feed along forest edges. Because grow sites break apart these forest landscapes, they are likely source points for exposure," lead study author Mourad Gabriel said in a statement.
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The authors noted that an estimated 4,500 to 15,000 private cultivation sites are in Humboldt County, but only a few permits have been enforced. Therefore, there is no management oversight.
"When you have thousands of unpermitted grows and only a handful of biologists that regulate that for multiple counties, we're deeply concerned that there aren't sufficient conservation protective measures in place," Gabriel said. "If no one is investigating the level at which private marijuana cultivators are placing chemicals out there, the fragmented forest landscapes created by these sites can serve as source points of exposure for owls and other wildlife."
While researchers say more investigations need to be administered to better understand the magnitude of the contamination, they believe their findings are strong.
"We're using our collections,” coauthor Jack Dumbacher said, “to build a concrete scientific case for increased forest monitoring and species protection before it's too late to intervene."
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