That sounds even worse. These invasive species always present a danger to the native fauna that don't know to avoid them. If they get gradually poisoned instead

That sounds even worse. These invasive species always present a danger to the native fauna that don't know to avoid them. If they get gradually poisoned instead, they might never develop the avoidance behavior and may lead to biomagnification of the toxin. PS: This is just a speculation. Any clarification from an expert is appreciated.