@ andrecas: Helifor has usually at any given time two or three of them in their helicopter maintenance yard in Campbell River. I guess they use them in support of their heli-logging operations.

Having worked in the pulp and paper industry for more than 40 years, seeing your photo peaked my interest. Unusual to see such a line-up of boom/dozer boats at an airport. I'm tempted to call the airport or Helio Industries in Campbell River.. :)
Anyway, at the 1:35 minute mark of video you can see a boom boat in action..
www.youtube.com/watch?v=kG-dU4ueeCw

Well Dirk ,they are a sort of small pusher tugs then.
Thanks Dirk for sharing photo and providing info.
Keep safe and stay healthy.
regards
Emmanuel.L.(Malta)

@ Emmanuel L: sidewinders are little boom boats used in wet log sorts. These ones stored at the airport belong to Helifor, a large heli-log company.

@ rarcand: Daleks? these are boom boats....

What are sidewinders? The only sidewinders I know are snakes or air to air missiles. And why are they stored in an airport if they are of a maritime nature?
Stay safe
regards
Emmanuel.L.(Malta)

Are you sure they are not Daleks? From this angle they do not look like very small tugs.