est ▁month , ▁July , ▁aver aging ▁, ▁which ▁is ▁among ▁the ▁highest ▁in ▁Ontario . ▁The ▁surrounding ▁lake ▁moder ates ▁summ ert ime ▁temper atures , ▁cool ing ▁the ▁flow ▁of ▁warm ▁air ▁masses ▁origin ating ▁from ▁the ▁G ulf ▁of ▁Mexico ▁and ▁as ▁a ▁result , ▁temper atures ▁above ▁ ▁are ▁rare , ▁with ▁only ▁ 4 – 8 ▁days ▁per ▁year ▁in ▁the ▁park . ▁ ▁Human ▁impact ▁ ▁Development ▁From ▁a ▁regional ▁perspective , ▁the ▁park ▁is ▁isolated ▁from ▁other ▁natural ▁areas ▁because ▁in ▁Es sex ▁County , ▁less ▁than ▁ 6 % ▁of ▁the ▁native ▁forest ▁cover ▁and ▁ 3 % ▁of ▁the ▁wet lands ▁remain ▁int act . ▁Much ▁of ▁the ▁area ▁( 9 7 % ▁of ▁it ) ▁has ▁been ▁alter ed ▁and ▁mostly ▁converted ▁for ▁agricult ure , ▁industry ▁or ▁urban ▁development . ▁It ▁is ▁also ▁located ▁close ▁to ▁major ▁urban ▁areas . ▁ ▁Bird - watch ing ▁It ▁forms ▁the ▁southern most ▁point ▁in ▁main land ▁Canada ▁( its ▁latitude ▁is ▁the ▁same ▁as ▁that ▁of ▁the ▁northern most ▁count ies ▁of ▁California ) ▁and ▁is ▁part ▁of ▁a ▁bird ▁and ▁but ter fly ▁migration ▁cor rid or ▁over ▁Lake ▁Er ie ▁via ▁Point ▁Pe lee ▁and ▁the ▁Lake ▁Er ie ▁islands . ▁Over ▁ 3 6 0 ▁bird ▁species ▁have ▁been ▁recorded ▁in ▁the ▁park . ▁The ▁peak ▁time ▁for ▁bird ▁migration ▁is ▁spring , ▁especially ▁May , ▁when ▁tired ▁migr ants ▁make ▁first ▁land fall ▁after ▁their ▁journey ▁north ▁across ▁the ▁lake