Reading this because it is a Campbell nom for this year, I'm walking into this as a properly fascinated reader. I mean, it's a western alternative history where hippos are the next big meat and it was ACTUALLY A THING. It might have been a bad idea in the real world, but the concept for a SF novella is pretty spectacular. 
 So how did it pan out? 
 Well. I like revenge stories as well as anyone and having these big monsters that crunch people with a single bite always makes for great river fiction, but I found my attention wandering. I think it might have just been me. The concept is great and the writing is okay, but it just wasn't enough for me to hang my hat on. 
 I'm sure others might get more out of this! I DO recommend this highly for anyone who loves the whole Western thing. I think I might not have been in the right mood, unfortunately.