Following complete removal of the last dam from the Elwha River it appears that the nearshore food webs have begun to repair themselves. During a recent lower river and estuary seining, the Coastal Watershed Institute (CWI) documented, for the first time, hundreds of gravid and spent eulachon Thaleichthys pacificus- a federally listed river spawning smelt (watch a video of the field observation here).
The eulachon’s common name “candlefish” derives from the fact that they are so rich in oil that, when caught, dried, and strung on a wick, they can be burned like a candle! Eulachon have historically been a culturally important species to indigenous cultures. Eulachon also provide such a significant energy source to the entire aquatic food web that they are federally protected. Eulachon spawn at the most upstream extent of tidal influence in a river and require fine sediments to successfully reproduce. Because the Elwha River dams altered sediment delivery to the lower river, eulachon and have been nearly absent from the Elwha system for the past six decades. Now that dam removal has re-established natural river sediment processes, we are thrilled to know that eulachon are returning to this restored habitat so quickly and in such abundance. The dozens of seals, sea lions, and thousands of birds are even happier!
In January 2015 Coastal Watershed Institute also observed the first ever Long fin smelt, Spirinchus thaleichthys, in the Elwha nearshore. Long fin are also river spawning smelt. This was a gravid female.
The term ‘forage fish’ refers to a group of pelagic schooling fish (including eulachon, surf smelt, long fin smelt, sand lance, and herring) that are a critical food source for larger fish, birds and marine mammals including Chinook salmon, bull trout, alcids, gulls, and seals, sea lions, and whales. Eulachon and longfin smelt spawn on fine grain sand in lower rivers thru winter and spring. Surf smelt and sand lance spawn in the mid and upper intertidal areas of very specific grain size beaches-surf smelt spawn here in summer-sandlance spawn here in winter. Herring spawn on eelgrass and seaweed during early spring. In healthy nearshore ecosystems, forage fish and forage fish spawning are prolific, but in far too many coastal areas they are experiencing significant declines.
For example, here on the Olympic Peninsula, forage fish spawning along the Elwha drift cell is a mere fraction compared to other areas, including the adjacent and intact Dungeness drift cell, where relatively abundant and consistent surf smelt spawn along feeder bluffs is supported by complex seasonal bluff feed rates and volumes of specific grain size sediment. In the Elwha nearshore, dam removal creates an unprecedented opportunity to jump start and restore these vital forage fish communities and the higher predators that depend upon them. And the Elwha drift cell provides a cautionary tale on how important it is to protect intact nearshore systems for forage fish, such as the Dungeness bluffs drift cell.
While spawning is low in the Elwha drift cell, it’s common to seasonally see extremely large schools of adult and juvenile sand lance (Ammodytes hexapterus), surf smelt, and herring (Clupea harengus pallasi) migrating along our shorelines and feeding in the kelp and eelgrass beds of the Elwha and Dungeness nearshore (see sand lance and herring in our nearshore here: http://vimeo.com/106125199 and video of a recent juvenile herring storm in the Elwha nearshore here: http://vimeo.com/104661826) . It is so important to protect these nearshore habitats critical for these important forage fish species.
In July 2014, Coastal Watershed Institute and a group of young National Geographic Explorers documented that surf smelt (Hypomesus pretiosus pretiosus) expanded their spawning range in the Elwha nearshore and spawned on new beaches that were created as a result of dam removal. You can read about our July sampling here. We continue to sample for new spawning areas for surf smelt and sand lance and other forage fish as they arrive. Stay tuned.
Ongoing field efforts to chronicle these unique ecological changes in the nearshore central Strait including the Elwha, Dungeness drift cells take many hands and ongoing funding. WDFW, WCC, DNR, UW, UVic, Salish Sea biological and our Peninsula College/WWU and other student interns and die-hard photographer partners are essential. A big thank you goes out to all of you for heavy lifting under all weather conditions! Funding for this work is provided by Olympic Peninsula Chapter of the Surfrider Foundation, University of Washington, University of Victoria, Patagonia, Puget Soundkeeper Alliance, Rose Foundation, Seattle Foundation/Hayes Family Foundation and private donations. Join us.