Standing still on the intertidal mudflats of Roebuck Bay is a fascinating experience, with the squishy mud underfoot crawling with quirky invertebrate animals that are either hunting for food or escaping the bills of hungry shorebirds. For migratory shorebirds, these invertebrates are the superfood to fuel their remarkable 10,000 kilometre annual migration to the northern hemisphere, where shortly after arrival in the Arctic, they will mate and produce a clutch of eggs.
With a major ‘benthic’ expedition on Roebuck Bay and Eighty Mile Beach in October 2016, the Roebuck Bay Working Group asked acclaimed filmmaker Paul Bell, to make a short film about the importance of the remarkable invertebrates that live in the glorious mudflats of these two Ramsar listed wetlands.
“Filming the many creatures of the mud gave me a chance to really spend time observing the whole system at work. Sometimes that meant lying in the mud for hours on end to finally get the shot of a worm or tiny crab, but there is something meditative about just sitting or lying in this case and watching. The massive tides come and go twice a day and there is continual change happening.
“The data that the team collected during the study will go a long way to preserving this asset into the future and has made me appreciate what’s out there even more,” Paul Bell said.
The film is impressive, with extraordinary aerial footage of the migratory shorebirds feeding on the animals in the productive mudflats. Close ups of the worms, crustaceans and bivalves the shorebirds feed are wonderful, as are the legs of volunteers descending into the soft mud!
The team of 100 who participated in the expedition included, scientists, landowners, ranger groups (Yawuru, Karajarri and Nyangumarta) and volunteers. Whilst the young and the brave ventured onto the mud to collect samples - supported in the deep soft mud by a hovercraft; others preferred to sort samples in the air-conditioned laboratory at the Broome Bird Observatory.
The impetus for the expedition was to conduct repeat surveys of the benthic invertebrates at the two internationally important mudflats, to discover if and how benthos abundance, diversity and distribution has changed.
In October 1999, almost the entire intertidal area of Eighty Mile Beach was ‘benthically’ mapped, whilst the benthos of the northern mudflats of Roebuck Bay was mapped in 1997, 2000, 2002 and 2006.
The information gathered from the 2016 benthos expedition is essential for informed management of these immensely valuable wetlands for migratory shorebirds, as they come under growing pressure from human interference on the East Asian Australasian Flyway, particularly on their staging grounds on the Yellow Sea in China.
The authors of the Field Report (Piersma, Pearson et al) recommend that the WA Government apply for World Heritage Status for the joint marine reserves of Eight Mile Beach and Roebuck Bay.
The expedition was funded by the Parks and Wildlife in partnership with BHP Billiton, with in kind support from NIOZ and Wetland Research and Management. The wonderful short film, was made by Paul Bell from Feral Films and funded by State NRM through the Royalties for Regions program