The number of fish in the Napa River appears to be growing.
This year, about 33,000 fish — representing 25 species — were trapped and identified by the Napa County Resource Conservation District.
“I think this highlights the need to conduct this type of monitoring,” said Jonathan Koehler, a senior biologist with the Napa County Resource Conservation District. For two years, the local agency has been using a rotary screw trap monitoring system to get an idea of what is in the Napa River.
Compared to the year before, only 119 steelhead smolts and one Chinook salmon were identified in the Napa River. This year, however, the total catch of Chinook alone was about 1,371 in the Napa River.
The verdict is still out as to what these results mean.
Are the improved populations the result of a healthier river, or better monitoring of fish populations?
“I interpret this as a positive trend,” said Koehler. “Maybe we are doing a better job (monitoring)? I am not sure right now.”
Results have also uncovered three new species of salmon are living in the Napa River.
It appears the fish found in the rotary screw trap are Sockeye salmon. It is a species more commonly found in the Columbia River that divides Oregon and Washington.
And for the first time, it appears the Sockeye salmon discovered in the Napa River, which is a species more common to the Columbia River that divides the Oregon and Washington.
The local resource district sent pictures of the fish to experts at the National Oceanic and Atmospheric Administration in Seattle for analysis.