Urban wetlands in Sydney, Australia, are are actively managed to reduce the impact of an invasive fish, Gambusia holbrooki, known locally as the plague minnow, on threatened green and golden bell frogs, Litoria aurea. The plague minnow preys on bell frog eggs and tadpoles. To reduce the effect of predation by this invasive fish species on native frogs, the local authority routinely drains some wetlands to create a fish-free environment for the frogs. But research suggests that the fish-free environment also benefits a local pest mosquito species, Culex annulirostris, a nuisance biter and vector of arboviruses. (Photo credit: Jayne Hanford)