Back in the 1980's Busselton GP Geoff Taylor was a keen underwater photographer, he would often go on research expeditions putting his hobby to good use.
On a trip to Ningaloo Reef, Dr Taylor was part of a team excavating the Rapid shipwreck with the WA Museum, a crew of people went off to look for a Japanese warship.
On the way back they spotted a whale shark offshore from Ningaloo Station and were quite excited when they returned to the group.
"That was just one sighting that I knew of, I was working in Perth at the time and decided I really wanted to go back to country medicine and be a rural GP up north," he said.
"I was told there might be a job in Exmouth, and I asked them to put my name down.
"I bought myself an underwater cine camera and I had this plan that I was going to go out and search for whale sharks, even before I went.
"I thought if there were whale sharks off Ningaloo Reef then that would be something worth pursuing. I had no idea we would find the enormous numbers that we found."
Dr Taylor spent more than 10 years counting, documenting and filming whale sharks off Ningaloo Reef in his spare time.
"We were out there every couple of weeks because I worked every second weekend, so every two weeks we would go out whenever we could and zigzag our way up the reef," he said.
"The first time I went out on the water I found two whale sharks, it was the second anniversary of the sighting at Ningaloo Reef.
"Then we did not see any for nearly 10 months, all of a sudden we started seeing them, the most that year was probably eight in one day."
Dr Taylor said after a few years of documenting whale shark numbers it became apparent something extraordinary was happening and whale sharks would aggregate at Ningaloo at certain months of the year.
"Very few people used to go down that coast at that time of year except for a few keen game fishermen," he said.
Dr Taylor published a paper in 1989 in the Western Australian Naturalist about his experience, and received a grant from Parks and Wildlife to do weekly aerial surveys.
In 1994, Dr Taylor published a book titled Whale Sharks: the giants of Ningaloo Reef which included stunning underwater images and discussions of his findings.
His book has recently been re-released, and Dr Taylor will be holding a book signing at Barefoot Books in Fig Tree Lane, Busselton at 4pm on Saturday July 27.
