I've been thinking about an alternative brand for the Dolphins for a while now.
So I thought about it and decide it needs to fit a few parameters; firstly it needs to maintain an aquatic animal theme, secondly it needs to make sense for the Brisbane market, thirdly it needs to be unique in major professional sports, and most importantly it needs to be at least as marketable as a Dolphins brand.
Anyway after some further thought I cam up with a bunch of ideas but, IMO, one stood out- the Sawfish.
Sawfish are charismatic, and badass, aquatic animals, that no other major sporting franchise that I know of is using as their mascot.
They used to be common in the Brisbane river until as recently as in the 50s, however due to habitat destruction, over fishing, and pollution they've seemly gone extinct in the Brisbane river (the odd unconfirmed sighting in the Brisbane River still pop up from time to time). That opens up massive marketing opportunities by getting involved with, and helping to raise money for, conservationist that are trying to grow sawfish populations in Australian waters.
Use a logo that looks something like this-
Call them the Brisbane Sawfish, and Bob's your uncle you've got the makings of a brand that is just as marketable as Dolphins, but isn't going to alienate people like the Dolphins inevitably would.