Every year Australian shores attract both locals and tourists from around the world for the chance to catch a glimpse of a humpback whale on their annual migration route to warmer waters. The opportunity to spot one of the most majestic animals in existence is too great, with many braving the wind and cold hoping for a glimpse of the acrobatic 40 tonne giants.
Humpback whales in Australian waters have become a regular sight during the winter months off the east and west coasts of Australia. In the autumn months they depart their Antarctic feeding grounds to migrate towards Queensland where they breed and raise their young. From September, they turn back towards the Southern Ocean and return home.
However, just a few short decades ago they were nearly hunted to extinction. Fortunately, protection was granted to these giants in the early 1960’s. Since then, both humpback whale populations that visit Australia have been recovering. In fact, the west coast population is one the biggest humpback whale populations in the world, and the east coast is home to one of the world’s most well-known humpback whale, Migaloo the all-white whale.
The annual whale count
For some, dusting off their binoculars and donning their winter jackets is just a fun day out whale watching. For others, it’s an annual ritual that cannot be missed.
Wayne Reynolds and Sue Rennie Wright are the latter. Since 1995 they have been travelling to Cape Solander, south of Sydney in the Kurnell National Park, just to watch the migration.
“It was the love of whales that kept me going for so long,” Wayne says. To him, humpback whales are the “most free-spirited whales, considering what we did to them”.
At the beginning the passionate whale watchers sat in the carpark on fold-up backyard chairs. Then, the annual northward migration whale counting event at Cape Solander became more and more popular, becoming a community event as more people joined the watch. Today, the group now known as the Cape Solander Whale Migration Study is one of Australia’s longest-running citizen science-based studies.
To assist the group, the NSW National Parks and Wildlife Service built an observation deck known as the “whale deck”. It would become the basis for the next 20 plus years of data collection.
Wayne, along with his team, watches for humpback whales coming from the south. Then the team records the whale as it passes the finish line, which is marked by an ocean marker buoy known as Waverider. Once a whale has passed the line, the team look to the south again and count the next whale passing through.
Enthusiasts turn published scientists
While the data they record sounds basic, it reveals important information about the recovery of humpback numbers.
This month, the team have had their work published in the journal Marine Mammal Science, with Wayne as co-author.
Their numbers revealed a 10 per cent growth in numbers of humpbacks on the east coast every year since 1997. This rate of growth in an encouraging sign of their recovery after the end of hunting. The observations also documented mothers with calves of both humpback and dwarf minke whales, showing that calving can occur before they reach their northern breeding grounds.
And while the team’s focus might be humpback whales, they also observed a variety of marine species such as Southern right whales, seals, turtles, jumping sharks. From these observations they’ve also captured data on species we known very little about in our waters, such as the endangered blue whale and species like false killer whales and killer whales.
This study shows just what is possible by citizen scientists. Using their passion, they’ve made an impact in whale research, filling in gaps that scientists haven’t been able to. The findings from this work have also contributed to informing State and Federal policy makers responsible protection of cetaceans in Australian waters and beyond.
Long-term wildlife studies are often not feasible and a challenge to keep running, let alone citizen science which in this case has been born out of dedication and commitment. This highlights the unique nature of this study, and it’s been a privilege to work with these dedicated cast of volunteers.
Providing not just data but tools to scientists
However, it’s not just the invaluable data that scientists have gained from working with the group.
Along with the Cape Solander Whale Migration Study, the whale deck has also played host to marine scientists conducting research in the area.
Not only myself, but a number of whale researchers have worked alongside this intrepid group of whale watchers. My research looked at the effects of the whale alarms (whale pingers) – small sound devices aimed at acoustically alerting whale to fishing gear presence. My colleague at Macquarie University, Maryrose Antico, even studied the watching activities themselves.
Both studies used a theodolite, also known as a surveyor’s tool to track whale movements in the area thanks to the 30-metre elevated height of the whale deck over the ocean.
While the whale deck has contributed to numerous studies, it’s the work of the Cape Solander Whale Migration Study which has remained dedicated to their mission of recording the number of whales.
Talking to Wild About Whales, Wayne highlighted the sense of community around the project. “Cape Solander is a real focal point for community education about whales and it’s been wonderful to be part of a close knit group of loyal volunteers.”
This article was first published on Australia’s Science Channel, the original news platform of The Royal Institution of Australia.
