The Coorong in South Australia is a system of wetlands and sand dunes around the area where the Murray river meets the Southern Ocean.
MIKE SEXTON: For thousands of seabirds, the Coorong is an inviting 100km long strip of wilderness, where the Murray River meets the Southern Ocean. It's home to the country's biggest pelican breeding colony.
But scientists studying the Coorong are alarmed by the recent decline in the pelican population.
DAVID PATON, UNIVERSITY OF ADELAIDE: They just hardly bred at all for the last three or four years and it's directly tied I think to the absence of fish in the south lagoon.
MIKE SEXTON: What makes the Coorong such a wildlife paradise is the confluence of salt water from the ocean and fresh water from the Murray.
But dramatically reduced river flows in recent years are having a major impact.
Without the fresh water to dilute it, the sea water slowly evaporates, leaving behind extremely salty conditions.
MIKE GEDDES, UNIVERSITY OF ADELAIDE: The Coorong, over the last few years, has got more and more saline, so it's now down in the south lagoon at 3 or 4 times sea water, 120 parts per thousand. At that salinity, none of the normal estuarine animals can survive.
MIKE SEXTON: Ecologist Mike Geddes and ornithologist David Paton have been monitoring the Coorong for almost three decades. This film shot 20 years ago shows the abundance of birds, and the major food source, rupia weed, which grew in underwater forests.
MIKE GEDDES: The rupia, which were big beds of green flowering plants, now we just find the odd patch here and there.
MIKE SEXTON: The university has three test sites for rupia, five years ago, 60% of the samples taken contained weed. This winter, one site recorded 2%, and the others zero. While the weed is disappearing, there's a new arrival that confirms a major ecological shift. As their name suggests, brine shrimp love salty water and they have never been recorded in the Coorong before but this year they're as thick as soup.
Without significant flows of fresh water, scientists believe the Coorong will continue its terminal decline.
A year ago, the Murray-Darling basin commission embarked on a five-year plan called the Living Murray to reclaim water for environmental flows. The success or failure of the programme will be decided by its impact on wetlands and forests in three states, including the Coorong.
The Living Murray program will not force irrigators to give back water. Instead, $500 million is being spent with the aim of pre-claiming 500 gigalitres of water by 2009, the equivalent of Sydney Harbour. But critics believe that may be too late.
MIKE GEDDES: We'll get 500 gigalitres and, as I say, that's a good thing. But that really, that in itself isn't going to do much to regenerate the ecology of the Coorong. We're going to need either much bigger managed flows and if we can get to the 1,500 gigalitres we'll be start to getting the volumes we want.
DAVID PATON: The longer we delay, the harder it's going to be to recover this system and, in fact, we put at risk ever being able to get it back to what's like in the 80s, when we, as Australians, signed an agreement to say we would look after the system for those migratory waders.
The Coorong is in South Australia. It extends for around 150 kilometres, from where the Murray River flows into the Southern Ocean.
We use an before nouns with a vowel sound. Follow the link to our language library below for more information.
more information: a & an
This is the shortened or contracted form of it is and hence has an apostrophe. For more about spellijng the words it's and its, follow the link below.
more information: its & it's
Notice that the superlative adjective 'biggest' is used with the possessive 'country's'. For more about superlative adjectives, follow the link to our language library below.
more information: superlative adjectives
Here bred is the past tense of the irregular verb breed. Follow the link below to find out more and to listen to some examples.
more information: breed
This is the shortened or contracted form of it has and hence has an apostrophe. For more about spellijng the words it's and its, follow the link below.
more information: its & it's
Confluence means flowing or meeting together.
The salt water comes from the ocean. Itís also called seawater.
Fresh water is river water - itís not salty.
Dramatically means greatly - in a sudden and noticeable way.
The term river flows refers to the amount of water running through the river.
Notice the use of the present continuous tense to talk about something happening now and conrtinuing into the future. For more about the present continuous tense, follow the link to our language library below.
more information: present continuous tense
To dilute means to make weaker or less concentrated. Usually, the fresh water mixes in with the seawater and makes it less salty. It dilutes the seawater.
The adjective saline means containing salt. The water has become saltier.
Salinity is a measure of the proportion of salt in water.
Estuarine means from an estuary. Estuarine animals are animals that live in an estuary.
Grew is the past tense of the irregular verb grow. Follow the link below to find out more and to listen to some examples.
more information: grow
Here spent is the past participle of the irregular verb spend. Follow the link below to find out more and to listen to some examples.
more information: spend†
What other words are there for salty and saltiness?
view the spotlight >
|Australia Network Home Contact Us Help Legals © ABC 2011|