|Appearances||Ecco the Dolphin|
They actively chase and attack Ecco. Due to their brown colour, they sometimes blend in with the environments of the prehistoric stages and can surprise the player. These enemies have the reputation of being one of the most annoying creatures in the Ecco games, as they will pursue Ecco relentlessly from area to area and screen to screen attacking aggressively until destroyed. They can be defeated with the Charge Sonar or charge attack.