I chose a simple approach with the stern; self-amalgamating tape wrapped around the end forms a watertight seal. The stern can be semi-permanently sealed as if does not come apart during assembly.
The bow on the other hand has to be peeled open to remove the frame from the skin. The skin at the bow is first joined by an eight foot long zipper. The zipper is protected by two split flaps of deck material, this split is then covered by a third flap which is held in place on one side by pvc cement to the deck and on the other side by two inch wide industrial Velcro. These deck closing mechanisms all taper down to a sharp bow, where there is a small hole, perfect for water to enter as the bow goes through a wave.
A common approach is simply to wrap the bow with electrical tape after every assembly. I chose to spend some time last night to bond and seal a neoprene nose cone which slides onto the bow like a prophylactic over the top of all the flaps and zippers.
The result is visually appealing, and this weekend I will see if it seals the bow sufficiently. It may also act as a protector should the bow bump into rocks or other vessels.