The other thing that the water cops enforce is the equipment requirements which vary with the size of the boat. I think the penalty is $200 for each missing item. Some of the things that are required are:
Rowboat, canoe, kayak up to 6 metres in length (19'8")
Life jacket or PDF for each person on board
Buoyant heaving line 15 m (50')
Reboarding device / ladder
Hand-bailer OR bilge pump
Sound signalling device
Navigation lights [Not required unless operated at night or in restricted visibility.]
Magnetic compass [not required within sight of navigation marks]
Radar reflector [not required under most day and near-shore use]
Over 6 metres: Watertight flashlight, 6 Type A, B, or C flares
Personal Watercraft PWC
Life jacket or PDF for each person on board
Buoyant heaving line 15 m (50')
Reboarding device / ladder
Manual propelling device (oar) OR anchor with 15 m (50') of rode
Hand-bailer OR manual pump
Watertight flashlight OR 3 approved Type A, B, or C flares.
Sound signalling device
Navigation lights [Not required unless operated at night or in restricted visibility.]
Magnetic compass [not required within sight of navigation marks]
Radar reflector [not required under most day and near-shore use]
Class 5BC fire extinguisher
Up to 6 metres in length (19'8")
Life jacket or PFD for each person on board
Buoyant heaving line 15 metres
Reboarding device / ladder
Manual propelling device OR anchor with 15 m (50') of rode
Hand-bailer OR manual pump
If equipped with motor: Watertight flashlight OR 3 Type A, B, or C flares
Sound signalling device
Navigation lights [Not required unless operated at night or in restricted visibility.]
Magnetic compass [not required within sight of navigation marks]
Radar reflector [not required under most day and near-shore use]
Class 5BC fire extinguisher if equipped with inboard engine, fuel tank, fuel-burning stove, fridge or heater.
6 - 9 metres in length (19'8"-29'6")
Life jacket or PDF for each person on board
Buoyant heaving 15 metres
Life buoy attached to buoyant line 15 m (50').
Reboarding device / ladder
Manual propelling device (oar) OR anchor with 15 m (50') rode
Bailer OR manual pump
Watertight flashlight
6 flares: type A, B, or C
Sound signalling device
Navigation lights [if operated at night or in poor visibility]
Magnetic compass [not required within sight of navigation marks]
Radar reflector [not required under most day and near-shore use]
Class 5BC fire extinguisher if vessel equipped with motor
Class 5BC fire extinguisher if fuel-burning stove, fridge, or heater
9 - 12 metres in length (29'6"-39'4")
Life jacket or PFD for each person on board
Buoyant heaving line 15 m (50')
Life buoy attached to buoyant line 15 m (50').
Reboarding device / ladder
1 anchor with 30 m (100') of rode
Manual Bilge pump OR bilge pump
Watertight flashlight
12* flares of Type A, B, C or D, not more than 6 Type D.
Sound signalling device [horn]
Navigation lights
Magnetic compass
Radar reflector [not required under most day and near-shore use]
Class 10BC fire extinguisher if vessel equipped with motor
Class 10BC fire extinguisher if vessel has fuel-burning heater, stove or refrigerator
That said, in 35+ yrs of boating i've only been subjected to a spot search once and from what i understand, most OPP officers will let you off with a warning if it appears that you are trying to comply with all the rules but have some minor infraction. In addition all boaters in Canada are required to be licenced or show proof of competency from their province/state or country.
Here's a link to the official
Transport Canada website that applies to US boaters entering Canadian waters. Note non-residents do get some breaks.