River Herring Numbers Climb at Olneyville Ladder

By ecoRI News staff

PROVIDENCE — From March through May, Woonasquatucket River Watershed Council (WRWC) volunteers counted a record number of fish swimming through the fish ladder at Rising Sun Mills dam in Olneyville.

On April 16, 71 river herring, also known as alewives or buckeyes, swam through the gate in 10 minutes. Similar numbers were recorded around the times of the full moon. These fish swim from the mid-Atlantic Ocean to spawn in the fresh water where they were first hatched.

About 40 volunteers annually help count fish as they pass through the Rising Sun fish ladder. More and more swim by each year, but this year was particularly surprising:

2011: 7,269

2012: 9,264

2013: 12,336

2014: 39,518

“Thanks to years of hard work with our partners, we are really starting to see results,” said Alicia Lehrer, the WRWC’s executive director. “The young fish, or fry, born and raised in the Woonasquatucket now return here to spawn as adults.”

For generations, these fish arrived in the city and stopped at the base of the Rising Sun dam. Blocked from moving further upstream, some spawned in the river near Donigian Park on Valley Street.

The WRWC built the Rising Sun dam fish ladder in 2007. This is the first barrier on the river that fish can now pass. During the next few years, the WRWC took down two more dams and built a second fish ladder. Now fish use the whole river to spawn, up to Manton Dam in Johnston. The WRWC hopes to build a special nature-like bypass around that dam in 2015, but funding is limited.

Young herring leave the river in September and October for their adult lives at sea until they return to spawn. Commercial fishing, getting eaten by larger fish and, until the ban, recreational fishing had decreased their population. This has been a link that was almost broken in the natural food chain: no herring, no larger fish.

Historical records once described these same fish as “running silver” in the coastal creeks of New England.