Monkey Mia Seagrass Restoration Project

OG are proud to have teamed up with Perfect Nature Cruises and OzFish to sponsor the Monkey Mia seagrass restoration project. Some people may ask, it seems like a random sponsorship and how did this come about? On a holiday to Monkey Mia in April by OG Director, Ben Barsanti, a family outing with Perfect Nature Cruises to observe dugongs, turtles and dolphins presented an unexpected opportunity. We’ll get to that in a minute…

The Monkey Mia region is home to 10% of the vulnerable to extinction Dugongs that are remaining in the world (100,000 remaining and diminishing due to habitat loss and hunting in northern/eastern Australia and Asian countries). A dugong eats approximately 50kg of seagrass per day however this is not the cause of low levels of seagrass.

Credit: 3 Island Whale Shark Dive

Did you know back in 2011 an extreme marine heat wave occurred were the water temperature around Shark Bay to rise to 30 degrees? This was the perfect temperate for an algal bloom to thrive and attacked the seagrass which filled the water, turning it black, not allowing sunlight to penetrate the seafloor, breaking down the chain of photosynthesis.

The direct result of this was the loss of 1,000 square kilometres of the world’s largest seagrass meadows or 1/4 of the world’s largest marine carbon sink, measurable at 37% loss. As a result, this has directly affected the fish, prawns, crab stocks, turtles, and of course, the Dugongs. An interesting stat, seagrass meadows only make up ≈0.2% of the world’s oceans but they are responsible for absorbing 10% of the world’s carbon per annum.

The water clarity has since recovered, however the area was left with an eroding underwater desert. Enter Perfect Nature Cruises, a family owned and operated business in Monkey Mia who had an formulated a plan to replant seagrass and initiated a predominately self-funded trial in 2023. This trial consisted of laying specially designed degradable hessian bag filled with local sand and embedded with seagrass seedlings on the sea floor from the back of their catamaran!

The trial was quite successful and to increase the scale they were looking for sponsors. Right place, right time and right number of beers on the cruise and OG become a proud sponsor. In 2024, the team sourced a dedicated seagrass vessel “Norwest Lady” and almost doubled the scale from 2023 by laying 60 tons of bags in just under 4 weeks. As part of this project, they also collected 4,000 living seagrass seedlings from the beach and implanted them into the sandbags giving them a second chance at life. From research dives to check the progress of the seagrass project, it appears about 80% of the laid seedlings have taken and started to thrive which is an outstanding result.

Fast forward 3 months since the sandbag deployments and it was time to conduct the first official research dives to evaluate the project. In late October, members of the seagrass restoration team, University of WA (UWA) and WA Department of Biodiversity, Conservation and Attractions (DBCA) conducted a joint dive of the 2024 restoration site. The results were very positive with the surveyed area exceeding expectations for survival rate and secondary attachment.

Buoyed by the success of this 2024, planning is underway for 2025. Stay tuned for updates at OzFish.