Selkirk took the name of a dead Scotsman called Alexander Selkirk.
The original Selkirk was a sailor on a poorly run, poorly manned, poorly maintained vessel in the Early 18th Century. He had the good sense to put in for some vacation time on a small Pacific island, only a month or so before the whole damned mess sank. He lived alone on the island for more than four years, and was eventually an inspiration for that story by Daniel Defoe.
The new Selkirk is just some guy who also wants off the boat. Lacking a proper island in nature, he has endeavored to conjure his own in the thin air.
You might find him here: