@sumac,
sumac :
i don't know where you live .
we are living on the edge(literally) of eastern lake ontario and the greatest number of flyovers are the canada geese - they'll be coming north anytime now - up until about 20 years ago we wouldn't see them going north until early may - so something must have changed .
unfortunately , thousands of the geese no longer go all the way north but stay right on the grassy shores of lake ontario . they can make many places simply a mess - had to give up viviting some parks since they are overrun with canada geese - the excessive droppings are pretty messy - not pleasant to walk though .
i assume that at a certain point there'll probably be a reasonable balance achieved by mother nature .
"cormorants" present another interesting story .
at the presqu'isle park ther are a number of colonies on some small offshore islands .
some 30 years ago the cormorants were almost wiped out through overuse of herbicides and pesticides - but they have come back with a vengeance .
some islands in lake ontario have not a single living tree left on them - the excrement of the birds has killed them off .
again "i assume that at a certain point there'll probably be a reasonable balance achieved by mother nature . "
Quote:The Rise of the Double-crested Cormorant on the Great Lakes:
Winning the War Against Contaminants
The Double-crested Cormorant (Phalacrocorax auritus), a large fish-eating bird now found throughout the Great Lakes, has undergone dramatic changes in population over the last three decades. Devastated by the effects of toxic chemicals, the number of nesting pairs decreased by 86% from approximately 900 in the early 1950s to a mere 125 in 1973. The cormorant disappeared as a nesting bird on Lakes Michigan and Superior and only about ten pairs remained on Lake Ontario.
From 1973 to 1993, however, the cormorant population increased over 300- fold to more than 38,000 pairs.
The cormorant is now more numerous on the Great Lakes than at any time in its previously recorded history.
hbg
both the canada geese and cormorants are interesting to watch .