I stumbled upon a post-apocalyptic webcomic that had a guy journaling about the end of the world; his (barely) surviving group was on an island, and they see a zombie(not really)/infected/crazy person who'd caught a dolphin and was lung-fucking the blowhole. One of their non-infected teens was out fishing, but too close. They put down the one crazy with a rifle shot, but 4-6 more crazies found another boat, and over-took the kid, and almost made it to the island, but the survivors blew them up/set them on fire with an underwater bomb.
Unfortunately, I never got a name for this comic, so it's too hard for me to find with google. I do have the images saved (somewhere), but no server-space to host them (to link to here with).
A name, or preferably a link to an archive would be good