COHO
oncorhynchus kisutch · a.k.a. silver salmon, silvers
- bright silver sides
- spots on upper tail lobe only
- white gums, dark mouth
- trim, acrobatic build
THE RUN AT THE LOCKS
the silvers close the season. coho reach the ballard locks fish ladder in late august, peak from mid-september through early october, and straggle through into november. from the ship canal they scatter across the watershed — many into the little creeks that thread through the city itself.
▶ will you see salmon today? check the forecastLIFE STORY
- the acrobats of the run — coho clear falls six feet high on the way upstream.
- they come home fast: roughly eighteen months at sea, the shortest ocean tour of the three runs.
- coho spawn in seattle’s own creeks — thornton, longfellow, pipers — city water with wild fish in it.
- the first big fall rains are their starting gun; a wet week in october sends silvers up every creek mouth in the watershed.
- their eggs overwinter in river gravel — each about the size of the pebbles that hide it.
THE NUMBERS
the fish ladder counted 28,150 coho in 2025 — the biggest run of the year, half again the size of the sockeye return. when the silvers are in, the viewing windows earn their keep.
ASKED ABOUT SILVERS
what's the difference between coho and chinook?
check the mouth and the tail. coho: white gums, spots on the upper tail lobe only. chinook: black gums, spots across both lobes — and a much bigger, deeper body.
when do coho run at the ballard locks?
late august into november, peaking mid-september through early october. they are the last run of the year.
do salmon really live in seattle's city creeks?
yes. coho spawn in thornton creek, longfellow creek, and pipers creek — urban water, wild fish. they arrive with the first big fall rains, having passed the ladder weeks before.