Framlingham has lost 80 per cent of its koala population in just nine months following a koala management program aimed at addressing overpopulation in the area.
The animal numbers have dwindled after 200 koalas were removed from the township and translocated to other forests in October last year.
Carried out by the state environment department, the koala management program sought to address high koala numbers, declining tree health and loss of food trees, such as Manna Gum and River Red Gum.
It included koala health checks and fertility control of female koalas to reduce breeding rates.
A visit to the site this month revealed a significant reduction in koala numbers.
"DELWP visited the Framlingham township in November 2018 and again in July 2019 to monitor koala density and tree health," DELWP's acting regional manager of environmental compliance Mark Breguet said.
"The population of koalas is significantly reduced as a result of the active management by DELWP.
"From a recent survey, it is estimated that there is at least an 80 per cent reduction in koala numbers in the area."
He said trees affected by overfeeding were looking better.
"The trees affected by over-browsing in 2018 are markedly recovering as a result of the koala management program," Mr Breguet said.
"Trees throughout the township are generally exhibiting increased foliage growth, however some large old trees in the township and along the Hopkins river were unfortunately not able to recover.
"Residents spoken to are generally happy with the results of the management program, with many of the trees recovering and a much more sustainable koala density continuing to live in the township.
"Some preferred food trees continue to exhibit reduced canopy cover or signs of defoliation, and it will be important to continue to monitor the health of the koala population and their habitat."
The department said the program was necessary due to a significant increase in koala numbers at Framlingham over the last decade.
It's believed to be the result of koalas that were displaced and searching for new habitat following the Framlingham Forest fire in 2005-2006.
The majority were translocated to Claude Austin and Fergusson's State Forest south of Rocklands Reservoir, west of the Grampians.
From a recent survey, it is estimated that there is at least an 80 per cent reduction in koala numbers in the area.Mark Breguet, DELWP
Roy Baker, site manager at the Framlingham Aboriginal Trust, said the koalas in the Trust's forests were happy and healthy.
"We're on the other side of the township so we haven't had any koalas removed and it doesn't appear that we have an overpopulation," he said.
"They seem to be happy and the trees are surviving."
The koala population at Tower Hill has dwindled to a low of 60 after Parks Victoria carried out a cull 30 years ago.
"A mass relocation of more than 800 koalas from Tower Hill Wildlife Reserve occurred nearly 30 years ago to manage what was an unsustainable population," Parks Victoria ranger team leader Ben Hammond said.
"Many koalas were in poor health and they were at risk of killing their food source from over-browsing.
"For the past 20 years there's been a fertility control program to support a sustainable and healthy population of koalas and to maintain the Manna Gum habitat they need.
"Our latest count indicates there are between 60 and 80 koalas in the reserve, a population that is appropriate for the habitat available to them."
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