I am not familar with the layout over there and if the pier is withing the city limits or what type of city ordinances they have for bows and/or guns. Your best bet is to check with a District 9 CO or the state park for that one question.
http://www.michigan.gov/dnr/0,1607,7-153-10366_15383-24666--,00.html
http://www.michigan.gov/dnr/0,1607,7-153-10366_15383-24666--,00.html