The US National Oceanic and Atmospheric Association (NOAA) has released data from one of its river restoration projects that helps small fish to migrate between rivers and the Atlantic ocean.
By helping this small forage fish navigate past dams built on the river, NOAA hopes to improve their populations and in turn the populations of commercially fished species which feed on them.
In 2013, a fish lift was installed on the Milford dam on Maine’s Penobscot River. The lift – an elevator that carries fish over the dam – is already working.
In 2015, less than 600,000 river herring passed over the dam. That number has more than doubled to 1.25 million fish so far in 2016, according to the Maine Department of Marine Resources.
A separate report funded by NOAA in 2015 found many small, forage fish in the stomachs of more than 60,000 big fish – such as striped bass, cod, and spiny dogfish – confirming that helping forage fish rebound supports the big fish caught at sea.
NOAA is planning to build seven new fishways on Maine rivers between now and 2020, in addition to improvements to existing fish passage.