Arrow5......my text does not have that information .......

but it is fair to assume he was an Australian civilian
Further investigation reveals our mystery man was earlier Knighted [Sir XXXX YYYYY]..........but this was prior to a higher salutation of "heraldry" or "Nobility"
So we know he was a British Admiral...[by his uniform] ...his later salutation of "heraldry" or "Nobility"...was not Lord or Sir

Just to complicate matters

...the vesel on which the image was taken was built in 1906 & taken up by the RN in 1915 as HM Suva...prior to delivery as HMAS Suva in 1919
I am going to post this & then look at British Heraldry in GOOGLE ....Derek