That's one of two ex-military American locomotive cranes the North Coast Railroad got a few years before they shut down. The other is rapidly being consumed by forest undergrowth up at Scotia:
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The one at Dos Rios is numbered C-145, while the one at Scotia is the C-146.
There is a Burro crane on the NWP, specifically one the Eureka Southern inherited with their purchase of the Arcata & Mad River Railroad. It has been at Shively since the NWP shut down and is just visible in the sattelite imagery here:
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Last I knew, this one still carried full A&MR lettering!
Jeff Moore
Elko, NV