Warming waters and permafrost thaw could lead to population declines.
"Selawik River"
Crews working to clean diesel spill in Northwest Arctic village water treatment plant
Officials say the fuel was transferred from a city fuel tank to the plant tank, though the transfer was left unattended for about 7 1/2 hours before the operator was alerted to the spill and shut off the valve at roughly 10 p.m.