Warriors of the sea

My life has double joy at the moment. Not only am I able to walk again without pain after my knee surgery, but in doing so I have fallen into a love affair with mangroves. Well-being for me right now consists of a combination of a titanium prosthesis and drab looking shrubs growing quietly on our foreshore. Maybe I am easily pleased!

I was introduced to mangroves nearly sixty years ago: as a third-year geography student at university I researched mangrove habitat as part of the course. Memories of mud, squelch and mosquitoes at Corner Inlet are still with me, but I had no idea how that trip would come full circle and be part of my life today.

Then came my life in West Papua in the eighties. I delighted in the pristine environment of Manokwari on the Bay of Doreri, the mountains rising to 5000 feet out of the water, the tropical growth and our own private white sand beach in paradise. We were surrounded by mangroves but I was too busy having babies and coping with primitive living conditions to explore very much. I know now that over half of the mangrove habitat in Indonesia is located in this part of West Papua and that the trees play an important part in everyday life there.

Fast forward to the present and Western Port Bay on the eastern side of the Mornington Peninsula. I have just moved to Hastings where the whole foreshore is edged with mangrove swamps. To the south, Warringine Park hides a stunning coastal boardwalk through the wetlands, arriving at Jacks Beach at the Bittern end, near my old home. It connects me like an umbilical cord, with the familiarity of the mangroves and samphire habitat embracing me like amniotic fluid.

My recent discovery is that these mangroves in Victoria are way south of their comfort zone, and the ones at Miller’s Landing in Corner Inlet in Gippsland are the southernmost in the entire world! For some reason, the highest, the furthest or the most extreme of anything is interesting, and mangroves are no exception.

I have been observing the Hastings bushes, aviccenia marina, over the winter as I have extended my walk a little further each week as my knee has strengthened. They surround the whole of Western Port Bay, but from the path in our Hastings foreshore I can almost touch them. Diadromous (surviving in both fresh and salty water), they command the tidal flats. When the tide is out, they are exposed and the breathing roots (pneumatophores) stand upright, absorbing oxygen. When the tide comes in, just the salt-excreting leaves at the top are visible, and the young bushes are inundated.

At the winter solstice, the flower buds are visible, waiting for some warmth to break open into white flowers. Later, the fruit will fall off into the water and float until roots develop. Some make it into the mud and a new plant is born. Like mammals, these unique plants give birth to live young (vivipary). Tough stalwarts of the sea, they can survive in briny water with double the salt that other plants can tolerate.

I read that they clear the seawater of sediment, they break the power of stormy waves and surges, provide wood for building, and in earlier times, were food and medicine for indigenous peoples in the area – the Bunurong. Most importantly, mangroves create habitat for uncounted species of birds, insects and crustaceans. There are migratory birds for which our mangroves are the last food before the Antarctic! The fish of Western Port Bay use the roots as a nursery for their spawn until they are old enough to survive.

The most significant fact for me is that mangroves produce blue carbon at a higher rate than any other plant: their dead leaves drop into the mud and are converted there into what our planet needs more than ever before. We must protect them.

Instead of deforesting the mangrove swamps, we need to protect and expand them. There was a scare in our area when the Australian Gas Light (AGL) company wanted to build a floating, hazardous gas factory in the pristine waters of the bay. The environmental destruction would have been horrendous; fortunately, people power managed to defeat the project after several years and thousands of petitions.

As I walk, I feel more protective than ever towards these new friends. On a recent return visit to Corner Inlet, the beauty was breathtaking. Healthy mangroves are surviving and thriving at nearly forty degrees south, quietly fulfilling their destiny as lungs, kidneys, protectors and global warriors. As the days lengthen and become warmer, I will be out walking, watching for the next part of their ancient life cycle, and will pay my respects to this unassuming part of God’s creation.