How are fish and other wildlife renewable resources? how are they nonrenewable resources?

When it comes to the natural environment what is renewable and non-renewable depends upon how quickly the resource can be renewed and how quickly it is being harvested (depleted.) 
You could cut a few trees on a wooded lot to het your home and it would be a renewable resource. If you clear cut all of the trees it would not be considered renewable because in the next season the same resource would not be available to you. (You would have to use another lot. If you had enough lots it would again be considered renewable.) 
There are stocks of fish in the oceans that were once considered endless. Modern methods have enabled us to catch more and more of the fish depleting the stocks to the point where they do not recover from season to season. Slowly they will decline to the point of extinction.
HOPE THIS HELPS