You can sometimes get more information on the most mundane boat (like this one) through this site.

I presume that it is used for maintenance on the canal by British Waterways.

I sat waiting at Corpach last night for a cargo boat that came up the loch, I thought it was waiting for the tide but it could not berth until this morning. They tried dropping anchor but the loch was deeper than they expected so they were going to go back into more open water overnight but the Corran Ferry told them where they could find an anchorage.

Martin