By Bellamy Pailthorp
August 6, 2014
Tiny forage fish don’t have the iconic status of Northwest species such as salmon or orcas, but the marine creatures at the bottom of the food chain play a critical role. So scientists are excited to see signs they’re spawning in new habitat created by the Elwha dam removals.
At the mouth of the Elwha River, a new stretch of sandy beach has formed over the past two years. Sediment that had been held back by two dams for nearly a century has washed down the river into the nearshore environment.
Anne Shaffer, a marine biologist and executive director of the Coastal Watershed Institute in Port Angeles, has been monitoring the coastline since 2006. She says now, for the first time, researchers have documented surf smelt spawning on the new river delta.
"It’s a literally a watershed moment for us — for the Elwha nearshore restoration associated with the dam removals. It’s an event that’s a hundred years in the making,” Shaffer said.
She says researchers found tiny smelt eggs in the softer sand samples of the new beach during a recent survey. The news appeared on the Coastal Watershed Institute blog on Tuesday.
And while many people have been focused on the question of salmon returning to the river, Shaffer says these highly caloric forage fish provide food for huge numbers of larger species.
“Chinook salmon, killer whales, larger baleen whales will feed on them, birds — they are literally the basis for the majority of our marine ecosystem,” she said.
Shaffer’s team is also sampling for sand lance, which spawn in winter.
The findings are consistent with other scientists documenting species quickly taking advantage of the new nearshore habitat, such as Dungeness crab, says Ian Miller, a marine ecologist with Washington Sea Grant who is also studying the dam removals' effects on the nearshore environment.
"I think it's great," Miller said. "It's another indication that organisms — and in this case, organisms of particular concern — are utilizing new habitat in the coastal environment around the Elwha river mouth."
Forage fish have been identified as species of concern by many groups, including the Pew Charitable Trusts.
Kurt Fresh, a fish biologist with the National Marine Fisheries Service who is studying the effects of dam removal on sea life near the mouth of the Elwha, says the eggs found on shore are right in synch with smelt his team has been finding lately in the water — much of it gravid, or ready to spawn.
"We did not see many smelt around the mouth of river in our net catches early on," Fresh said. "But we seem to be seeing a bump in numbers since dam removal happened."
That's especially fun to see, Fresh says, when so many sources are studying the environment with different funding sources and from different angles.
"It's all very complimentary," he said.
http://kplu.org/post/new-life-after-dam-removal-surf-smelt-spawning-mouth-elwha