Low water - tides out?

Still sunny when I returned home from work today so took a walk down to the water. The shoreline is all rocks at the moment and there are suddenly lots of cobs out in the bay - which made me realise just how shallow the bay is!

Not sure why the water level is so low - there are no tides this far up the Gulf of Bothnia so that's not it. Something to do with the moon maybe?