Printable JPG Great Blue Herons have a wingspan of up to 6 ft. 6 in. and can weigh up to 8 pounds. They will eat anything from fish to small mammals and can nest in colonies with up to 500 nests. With this bird, it's go big or go home. On second thought, if you're not going big, don't bother coming home! These "big-time" stats inspired the name "Great Blue." I hope you like it!