WOLVES REINTROCTED INTO YELLOWSTONE NATIONAL PARK HAVE RESTORED ECOLOGICAL SYSTEM.

I SAW ON MY TWITTER ACCOUNT A VIDEO SHOWING HOW WOLVES HAVE ALERED THE ECOLOGY OF YELLOWSTONE.
THEY HUNTED DEER ETC WHO WERE FEEDING ON TREE STEMS,THIS ALLOWED TREES TO GROW TALL,SOME TREES STABILIZED THE RIVER BEDS CAUSING THE RIVERS NOT TO MEANDER AND FLOOD,STOPPING EROSION OF RIVER BANKS.
ALSO BIRDS STARTED TO NEST ETC IN THE TREES.