A lot lot lot depends on the temperament of the hound. Maggie, our 50 lbish Lab would sit quietly between my legs with occasionally moving about as something caught her interest. A pleasure to paddle with. Anny, a 75 lbish Lab, was a wiggler. Countless near misses (and quite a few misses with all of us in the water) never made an impression on her. Still kayaking is about getting a bit wet, so Anny was always equally welcome.