A regime shift is gradually spreading through the archipelagos of the Swedish Baltic Sea coast, where shallow bays, previously dominated by pike and perch have one by one become dominated by one of their prey species, the three-spined stickleback. Now, research shows that the ability of the pike and perch to maintain dominance over stickleback increases if there are plenty of pike and perch close-by that can help the local population withstand the stickleback intrusion. The researchers also found that the resilience of the pike and perch populations decreased with increasing predation from grey seal and great cormorant.