RAIN lashed the Lauderdale Oval, but a band of nature-lovers and a white-faced heron were not to be deterred.
Wind and rain seemed appropriate for the excursion on this occasion. The object of the summer exercise was after all the study of probably the most neglected and misunderstood environment in the world of nature: the saltmarsh.
Born of storm and tide, it’s a vital habitat for fish, birds and insects so who was complaining about a little rain. Amid welcome swallows struggling in the wind to catch insects, and the heron with its view of fish under the water clouded by waves, it would have seemed churlish. So along with a resilient band attending this excursion as part of World Wetlands Day in February, I got a little wet, but it was worth it.
The event had been organised by Clarence City Council, which has a fair share of the region’s wetlands under its care, and the highlight was the launching of a book, A guide to the plants of Tasmanian saltmarsh wetlands by its author Vishnu Prahalad.
The saltmarsh is described as the forgotten, Cinderella environment because in reality it is not much to look at, flat and inundated with sea water. What’s more, it often smells like rotten eggs, native anaerobic bacteria releasing hydrogen sulphide as it works to decay matter under the water’s surface.
When I first developed my interest in nature I soon learned the saltmarsh environment is rich in birds, especially waders like godwit, curlew and oystercatcher. But I must confess I never really questioned why.
Now I have the answers. As Vishnu explained during his talk and walk, the saltmarsh is in fact one of the most productive ecosystems on the planet, rivalling that of the tropical rainforest.
These vast areas that have proven of no value to man – except for providing convenient places to dump rubbish, or fill to provide land for suburbia – play a large role in the aquatic web of life, delivering nutrients to coastal waters. They also support terrestrial animals and provide coastal protection.
The myriad insects fluttering across the saltmarshes bordering the oval gave a clue to the reason birds other than waders show so much interest in them. Both tree martins and welcome swallows fluttered about, and along the ground superb fairy-wrens scurried. I had never thought of the wrens as being marshland birds but Vishu’s observations confirms they are as much at home in saltmarsh as meadow and garden.
Another bird that also finds a happy home in the saltmarsh is the white-fronted chat, a species that could be a symbol of these wetlands along with the waders and, of course, the white-faced heron. The heron is, in fact, the most commonly seen bird in this environment across Australia.
Saltmarshes are dominated by dense stands of salt-tolerant plants such as herbs, grasses and low shrubs. The marshes are intersected by channels of water which carry nutrients on rising and falling tides and these shallow channels also act as nurseries for fish.
With his book, Vishnu Prahalad, is hoping to improve the profile of the plants of our salmarshes which he says “could use some human friends to recognise them and allow them their modest need for space on our coastlines”.
My focus might be on birds but I was surprised to learn that saltmarshes also have important uses for people – Abel Tasman fed his crew saltmarsh plants when he first landed in Tasmania, as did Captain James Cook, because they are rich in iodine. Tasmanian Aborigines ate the berries of pigface plants and now one of the plants called glasswort is attracting international attention with chefs who cook with it. There are about 10 different species of glasswort around the world.
I was not thinking food, however, when I toured the saltmarsh. I was thinking of all the birds they attract, birds that rely on them like the beautiful white-fronted chat and how much would be lost if we did not pay the saltmarsh more attention.