Most weekday afternoons and weekends, Towpathguy sees fishermen (men, women and children) trying their luck in the D&R Canal or in the Raritan River. On weekdays in the afternoons, the spillway at Landing Lane or the culvert at One Mile Run usually has one or more anglers with a rod and reel. Most of the time the fishermen are on foot and are close to one of the entrances; however, some carry their rods and reels on their bikes to get access to sites further from the entrances.
The fishing seems to be pretty good. The buckets frequently have nice size fish in them. Also, a few weeks (late August, 2008), Towpathguy watched a fisherman land a small bass. The favorite fishing spots are the cleared areas near the entrances, culverts and spillways, especially just downstream from the locks. Also, there are plenty of small areas on the canal bank that are large enough for a lone fisherman to cast. Occasionally, a jonboat with an electric motor can be seen trolling. DeMott Lane is a good place to put a boat in.
An article in Fishing and Hunting News a couple of years ago says the "most productive area" of the D&R canal is the stretch from the Griggstown Causeway to South Bound Brook. Apparently, winter is the best time to go for pickerel and crappie. The article also correctly points out that the D&R Main Canal rarely ices over in the winter. Towpathguy only recalls two winters in the past 20 when the ice was thick enough to support an adults weight. Most winters the slow moving current keeps the canal open.