Tunneltouser

Tunneltousers are a medium-sized amphibious creature that populates a number of the larger islands in the aquos archipelagos. Whilst they spend the majority of their time in water, they nest up in burrows dug themselves deep into the earth, creating whole cavern networks that technically go below sea level. Before the majority of mireiyans migrated to their underwater cities, tunneltousers were frequently used to help gather ores & minerals to use for their artistry, as well as extending the space available to them. Nowadays, when the archipelagos are less frequently used for whole groups of people to live in, tunneltousers on the whole live out their existence in peace, unhindered by mireiyan activity, though some are tamed & trained to be sold to other nations for use in their construction projects. This is especially useful when building near water, as tunneltousers seem to have an innate sense for nearby water, stopping digging before a point where said water could pose a risk.
Appearance
Tunneltousers resemble large otters, though with a number of key differences that help them with digging, such as their much larger front claws and a longer, more sensitive nose. They also have large tufts of fur above the eyes which the tunneltouser will bring down over their eyes whilst digging, protecting them from dirt & debris.
Diet & Behaviours
Tunneltousers predominantly sustain themselves on fish, though younger tunneltousers will supplement this diet with larger quantities of herbs & berries. Tunneltousers are a species that have a very seasonable pattern: winter is spent hibernating in their dug-out tunnels. Come spring, the newborn tunneltousers will be supervised by one or two elders to ensure they don't stray too far from the tunnel system & protect them from any opportunistic predators. In early summer, the tunneltousers will all go out in unison for the younglings' first swim. It can take a few days for all of them to get the hang of it fully, but mortality rates are very low, with the older tunneltousers rescuing any that find themselves in trouble. The bulk of summer the tunneltousers will stay in the same general area, but towards the end they may decide to migrate to other islands, separating into smaller schools should their numbers be getting too numerous. Once they've found a new area to call home, the rest of Summer & Autumn is spent preparing for Winter, finding mates & digging any additional burrows required.