Hello, in The Scepter of the Shifting Sands questline you have a lot of running to do. If you want to be more to the point like me I skipped running up and down Tanaris just for the mermaid part.
Draconic for Dummies - Quest - World of Warcraft
When you receive this quest you can just take the mermaid factor out by having a DK path of frost, Or if you could water walk and mount or levitate and mount that will work.
For my druid I glyphed Aqua form so I got 100% speed to the island without dying.
I am sure you can use the turtle and Crusader aura and get to the island mostly safe.
How ever usually people would have to go to find the (in my opinion) hard to find mermaid and then run back to the gnome then back down again. I hoped this helped some people!