Colin continues his journey up the western Irish coast, listening to natterjack toads for a bit before he waxes philosophical about why some bottlenose dolphins live as loners while seeking out human company. He then marvels at the incredible tenacity of the lamprey, and explains how the reintroduction of the pine marten is helping the red squirrel win back territory from the invasive gray squirrel. He makes one more brief stop to thank the long-eared bat from keeping the Irish mosquitoes from getting out of hand, finally completing his year-long journey at the Sea of Moyle.