(MENAFN) Exposure to pesticides in waterways is impairing crucial social behaviors in fish—such as grouping, territorial defense, and mating—according to new research led by Australian scientists.

Released Tuesday by the University of New South Wales (UNSW), the findings point to a troubling global trend: rising social isolation among aquatic species that could destabilize ecosystems well before large-scale species die-offs occur.

The team examined data from 37 studies covering 11 different fish species and discovered that even minimal pesticide exposure significantly disrupts social functions like schooling, aggression over territory, and most notably, courtship. These behaviors are essential for population survival and ecological balance, the UNSW statement explained.

“Pesticides are making their way into freshwater systems through runoff from farms, and even at sub-lethal doses, they interfere with brain chemistry and hormonal balance,” said Kyle Morrison, the study’s lead researcher from UNSW.

Among the chemicals identified, glyphosate was found to be particularly harmful to fish social behavior. The authors cautioned that studies conducted in laboratory conditions—often using only a few model species—may underrepresent the severity of pesticide impacts in natural environments. They urged the scientific community to conduct broader, more ecologically relevant research across a wider array of species.

Morrison additionally cautioned that Australia still permits some pesticides banned elsewhere, putting fragile ecosystems like the Great Barrier Reef at avoidable risk. He called for urgent cuts in pesticide usage and a worldwide move toward safer options.

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