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Date: Wednesday, October 28, 2015

±Ê°ù´ÇÂá±ð³¦³Ù:ÌýEastern Australian Waterbird Survey

Observer: Richard Kingsford

A crisp clear morning greeted us today, with a cold southeasterly off the ocean. We took off and flew over the unique Tower Hill wetland, where a crater was created 30,000 years ago by a volcanic explosion, leaving an island and surrounding lake. Surprisingly, given the dryness around here, it had water but because it was not on our survey band, we did not count it.

Tower Hill wetland, a wetland resulting from a volcanic explosion.  

Then west towards Port Fairy and a lagoon with lots of swans but that was it. The small wetlands west of Port Fairy were dry. One had was obviously now the local place to do a few doughnuts with its criss crossing car tracks. From here, a wind farm hugs the coast. I find it hard to think of these as an eyesore, given their generation of renewable energy. Yesterday we flew over the coal-fired power station and Anglesea and even so on the books to be decommissioned, there will always be a scar on the landscape from where the coal was dug up. Just west of Port Fairy, we finished Band 1 and so headed north to begin the easterly survey along Band 2, north of Kingston.

Wind farm west of Port Fairy

This is part of the dunal wetlands that make up the Coorong. We survey the most southerly wetlands on this survey but will be coming back late next week to survey the rest of the Coorong and its two magnificent freshwater lakes, Lakes Alexandrina and Albert. The wetlands run the entire 30km length of the survey band and so we go north; the first systems that hug the coast are very salty and seldom have many waterbirds. Too much salt is detrimental to aquatic biodiversity. Once we get to the top of Band 2, we usually hop across a set of north-south dunes and head south surveying the string of wetlands which nestle between the dunes. Backwards and forwards, north south, we do this until we have worked our way across each of the dune systems and covered all the wetlands. 

This part of the survey is usually a joy. The wetlands are highly productive and there are waterbirds everywhere. This year was a big disappointment on the wetland and waterbird front. Even the dunal lakes which usually had some groundwater were dry. There was one with water, and some small flocks of teal and banded stilts. They like these saline wetlands. Usually, you can see almost every species of waterbird on these wetlands which are shallow and productive. The diversity of waterbird is always an indication of a wetland which supports everything from invertebrates, aquatic plants, fish and frogs.

The one saline wetland with water in the most southerly part of the Coorong with a few flocks of swans, grey teal and banded stilts.

This part of the landscape is criss crossed with massive drains which take the water and drain most of the wetlands. Put in decades ago, they continue to impact on the wetlands of this region which must have been something to see once.

Large drains take water from the wetlands of the southeast out to sea.

Normally we would survey in this one part of the country for at least an hour, hardly moving east across the landscape because there are so many wetlands and waterbirds to count. Not today. Our interest was mainly with the deer which are now well established after a few years in the part of Australia. The wind was reasonably gusty, as the plane ‘bounces’ in the air.

A string of dry wetlands which would normally provide habitat for thousands of waterbirds in this part of South Australia.

After this – the landscape continued to be very dry. It is only in a wet year that we will find wetlands between this part of the Coorong and the town of Horsham. And this year was definitely not one of these. Eventually we reach the Wimmera River. It always seems a sad river with its white floodplains from too much salt and the struggling pencil thread of a river working across the landscape. No water here in any of the lakes. I always feel this is one the most degraded rivers in the Murray-Darling Basin. There are now so few floods to ever rejuvenate its parched floodplains and lakes.  A refuelling stop at Horsham breaks the day.

Dry wetland after dry wetland followed as we slowly headed east into a head wind. We fly down the Campaspe River but when delivering water and full as it was, there were only a handful of waterbirds.

Campaspe River with few waterbirds

The one jewel of a wetland system in this part of the country is the Corop wetlands or Wallenjoe system, with the lakes used as storages for irrigation water. Today, only Green Lake and a smaller lake nearby had water but surprisingly there were few waterbirds.  We can sometimes spend a lot of time surveying these wetlands when they all have water because they are so extensive.  All the many other natural wetlands in this system were dry. Nearby storages near had hundreds of pink-eared duck, always a sure sign that inland is very dry when they come this far south.

Surveying Green Lake, one of the Corop or Wallenjoe wetlands in the Goulburn-Broken River catchment.

Next big wetland was the large Waranga Basin, a storage constructed to hold water for irrigation. This again was one of the more unproductive wetlands we surveyed, as it usually is. A natural wetland of this size would be expected to have tens of thousands of waterbirds but this one today just had a few swans, pelicans, silver gulls and the odd ducks. It took a long time to fly around for relatively little result in terms of waterbird numbers.

Surveying Waranga Basin, a storage for water

From here to Lake Mokoan or Winton Wetlands, near Wangaratta but this was nearly dry with only some very small patches and few waterbirds. This is the first time that the lake has been dry in the more than two decades I have been flying this survey. This is probably due to the combination of decommissioning the lake as a storage and the dry year. We overnight in Wangaratta.

The dry lake bed of Lake Mokoan or Winton wetlands