BACKUP FILES FIRST! Go to the directory in which you installed the game
Ex: "C:Program FilesCarnivores 2" look for the folder named
"Huntdat" open it and then look for the file called "_res"
open it and here you will find all the changes you would want to
make.Save a copy of this file before you change anything in it.Never set
any number on that page to "0" or the game will not run.Ex: 
 name = 'T-Rex'
 file = 'tirex.car'
 ai        = 18
 mass      = 6
 length    = 12
 radius    = 400
 health    = 1024
 basescore = 25
 smell     = 0.85
 hear      = 0.8
 look      = 0.8
 shipdelta = 168
 danger    = TRUE
Change the health into 1 instead of 1024 also you can change the
smell(or any other sense) to 0.1