Most birders cover this area by slowly driving, stopping periodically and walking stretches. The section between Moncrief Line and the edge of the swamp can be quite good for spring migrants. The low pasture to the north of the road just before the swamp edge is occasionally flooded in spring and if so can host some shorebirds (e.g. yellowlegs, snipe, Solitary Sandpiper, etc.). The buttonbush swamp on either side of the road around the midway point along the road is a good spot for Solitary Sandpiper in spring, and both Virginia Rail and Sora in summer. The small ponds often host Wood Duck, Hooded Merganser, Green and Great Blue herons (the latter which formerly nested in the tall maples at the south end of the buttonbush swamp). In spring a variety of waterfowl and occasionally a Bald Eagle may be present at the river. 

The wooded swamp before the river is one of the most reliable spots for breeding Blue-gray Gnatcatchers in Peterborough County and the regionally uncommon Yellow-throated Vireo breeds as well. The numerous standing dead trees are attractive to woodpeckers, notably Red-bellied Woodpecker, which is now almost a guarantee at any time of year. Both Eastern Screech and Great Horned owls are present year-round. Large, highly-vocal flocks of migrant Rusty Blackbird are usually present in April and early May and again in October.

This location covers Mervin Line from Moncrief Line to the Otonabee River, a distance of around a kilometer. The single-lane road travels through an extensive deciduous swamp before dead-ending at the river. The road can be quite rough and occasionally deeply rutted; it may be flooded and impassable in early spring. There is no winter maintenance and so is usually closed to vehicular traffic in winter. All property on either side of the road is private, so all birding must be done from the road. If birding from a vehicle, find a safe place to pull to the side, such that other vehicles may pass. As it is a swamp with standing water during much of the year, mosquitoes and deerflies can be quite bothersome, so dress according to the conditions.