im currently building a pen that will be 210 by 70! this is the part that has the pond and i have an additional 20 by 20 already built that will connect to the new part the pond is about 60 by 20. the fencing will be about 5 feet high. i plan on putting only geese and sheldgeese and possibly my ruddy shelducks but probably not due to their aggressiveness. the birds i plan on putting in the pen will be magpie geese,red breasted geese,andean geese, bar headed geese, ornico geese, greater magellan geese and Abyssinian blue wing geese LOL! thats actually more of my wish list but i was wanting for people with experience with these bird sto talk mainly about how aggresive they are because almost every website ive been too doesnt really talk about it and i figured since they would have so much room i really wouldnt have to worry about it but i would still like to hear everybody's opinions thanks!