When I google like this: "Michael Larsen" Fremantle
I find some websites with info.
One is this one, which is his funeral announcement.http://trove.nla.gov.au/ndp/del/article/26866570
It asks the members of Capt. Michael (Jack) Larsen's union, the Harbor and Rivers Certificated Master's Union, to attend his funeral in the newspaper from Perth, The West, on Feb. 11, 1913.
It seems to even tell which company he worked for.
He is the Master of Messrs. Mellworth and McEachern??' company Tug the S. S. Torrens. (it's hard to read)
Maybe the union has old archives and information about him?