Experts encourage innovative method to combat invasive fish devastating local ecosystems: 'It's a real natural, sustainable solution'
Invasive tilapia have been threatening endangered cod populations in Australia's Mary River, but experts say the cod are biting back, the Australian Broadcasting Corp. reported.
Conservationists from Burnett Mary Regional Group performed a routine survey in April, which involved catching and testing some of the region's Mary River cod. Researchers were pleased to discover traces of tilapia in two of the cods' mouths and also documented an 80-centimeter (31.5-inch) cod eating a 40-cm (15.75-in) tilapia.
In other words, despite the fact that the tilapia are not native to the area and the cod haven't evolved to eat them, the endangered native fish have adapted and are eating them anyway.
"There was always the hope and suspicion that [the cod] were eating everything," BMRG CEO Tom Espinoza said. "It's provided a lot of hope for people that are invested in healthy cod populations across the board. … Hopefully in 10, 15, 20 years' time, we've got a population of large cod that can do the rest of the job themselves. It's a real natural, sustainable solution."
This is encouraging news, because as matters stand, the tilapia are a serious problem. They're invasive — meaning they came to the area from another region and thrived so well that it's damaging the ecosystem — and they eat the eggs and young of not only cod but also other endangered species such as the "bum-breathing" Mary River turtle, Australian lungfish, and white-throated snapping turtle.
Because the tilapia have spread to 26 of Queensland's 67 catchments, it's considered impossible for humans to eradicate them. Left unchecked, they could destroy the native species in the river, damaging the ecosystem that both people and wildlife rely on.
However, steps have been taken to control the population. For example, tilapia are being harvested to use as fertilizer for native plants.
Now that it appears cod are also eating the tilapia, there's a chance to achieve a new healthy balance.
Should we be actively working to kill invasive species?
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It depends on the species
I don't know
No — leave nature alone
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