There was so much below this frozen river to be able to keep track of. Walker and Midnight had been letting the current take them down the river while they focused on what they could see. Various species of monsters swam through the water, some didn't mind them and others went after them.
The blue salmon was an interesting monster that lived there and was barely the length of Walker's arm. It would rarely leave the river except when the ocean waters grew colder then it would head out to hunt for larger prey and grow seven times its size.
An interesting monster that would be a great source of food for hunting that he would be able to report to the merfolk who would frequent the area in this case. Otherwise, they saw more species of ice and water specialty crabs, and even another species of herb called false ice.