Addict,
Angling lingo can be confusing. Harvest trout, bluebacks, anyone?
Springers applies to both spring chinook salmon (all chinook are known as spring salmon in British Columbia, for further confusion) and to early returning summer steelhead of either hatchery or native origin. The Washougal, E.F. Lewis, and Kalama were once well known for a native run of springer - steelhead that were later augmented through emphasis placed on culturing the earliest returning summer steelhead to the Skamania hatchery on the Washougal River. A lack of harvest restrictions on those native fish pretty well eliminated them from present day populations. There continue to be some hatchery springers.
I have very occasionally heard the April steelhead run on the Skagit called springers, but they are more properly a late winter run fish because they will all spawn this same spring - May and June, with a very few into early July. A true springer steelhead may enter a river in March through May but not spawn until the following February or March, up to a full calander year away. Consequently, they have stored incredible energy reserves, making them a lucky find with hook and line. When I used to regularly fish for them, I landed maybe one out of four springers hooked. Hot fish! Hope this helps.
Sincerely,
Salmo g.