As a national park, fishing is subject to the National Parks of Canada Fishing Regulations.
For tackle:
17. No person shall, when fishing in park waters, use
(a) more than one fishing line;
(b) a fishing line having more than one artificial fly or other type of bait;
(c) a fishing line having an artificial fly to which is attached any live or dead natural bait;
(d) a fishing line having any combination of hooks capable of catching more than one fish at a time;
(e) a fishing line having more than one type of lure;
(f) a lure having more than
(i) two single hooks,
(ii) two gang-hooks, or
(iii) one single hook and one gang-hook;
(g) a gang-hook having more than three hooks; or
(h) a lead sinker or lead jig that weighs less than 50 g.
I didn't see anything specific to the Bruce Peninsula National Park, but that's not to say I did a particularly thorough job of looking through the act. You can go through it yourself here: http://laws-lois.justice.gc.ca/eng/regulations/C.R.C.,_c._1120/