As Ty wondered what to do as he floated near the bottom of the lake he caught sight of the many Salmon still swimming around in the lake. The eggs had been hatching rather quickly he realized, and many of the salmon where sinking down stream towards wherever the river would take them already.
Ty, however, felt a need inside him. Brushing underwater as he thought about this need. His vagina ached with it as he thought about it.
The pleasure and pride he's felt from making such a massive clutch of eggs, birthing a new generation from just him and Nichole alone. It felt so good to acknowledge that... And it had felt incredible when he'd done so.
His vagina ached again as Ty brought a hand to his currently taut stomach. He wanted, both consciously and unconsciously, to give birth again.
He wasn't consciously aware however, that becuase he possessed the vaginal processes of a Salmon, that his instincts regarding such things had changed to match. Salmon were meant to give birth, and he wanted more.
'I wish... I wish I was pregnant with a new clutch of eggs.' Ty thought as his wish before inflating his boobs, floating away from Nichole so she could rest in peace, and he could give birth to another generation.
He didn't crest the lake's surface, but Ty floated below the water as Salmon started to swim around him, Ty giggling, bubbles floating from his mouth as he started to push, moaning up more bubbles as his now distended stomach started to shrink, eggs once more pouring out of his vagina as the salmon around him scrambled to fertilize the new clutch.
For thirty minutes he birthed, until his stomach was normal once more. With a doopey and tired grin on his face Ty closed his eyes, quietly sinking back down to the bottom of the lake to rest near Nichole, the flowing water washing sand over him as he slept quietly.
But with his session of birthing he's given in more to his changing instincts, a change he wanted. Unaware yet of it, the skin around his vagina had flaked off to reveal shiny scales, the first and many changes to the him if he contiuned this path.