My Brittany is quite quickly getting harder and harder of hearing. It makes it tough for us to hunt, as she cannot really hear well enough to respond much when out in the field.
We hunt mostly tall grass and cattails, and thus she cannot check in visually very easily either. This means that she usually ends up lost in the middle somewhere, on point with no way for me to know what she is up to. I used to just whistle her in closer but know she never hears it.
What do you do with a deaf bird dog, especially a pointer?