This whale shark is on Murat Road, in Exmouth WA, next to the petrol station. It is called Ningaloo George, constructed by fibreglass.
The sculpture was created by Brian Paskins and erected in 2002 to celebrate the whale sharks visiting the Ningaloo waters each season, from March to June.
It is listed on Wikipedia as a big thing but is one of those that are smaller than the actual thing they represent. Another creation of Brian Paskins is The Big Prawn, also in Exmouth.
Feature photo by Aliceinthealice, CC BY 4.0 https://creativecommons.org/licenses/by/4.0, via Wikimedia Commons