The Algonquin to Adirondack Conservation Association, with a view to restoring and enhancing connectivity of this landscape, needs to document and understand the threats and opportunities related to connectivity. Among the most significant and problematic barriers to the corridor is the 401 Highway, intensive residential development and the urban barriers of the Town of Gananoque and Brockville. This study focused on the 401 Highway issue. A vital step in the process of enhancing and restoring the connectivity from the Algonquin to Adirondack parks regions is to develop an understanding of the nature and complexity of the 401 Highway as a barrier.

It was not the purpose of this study to enable more animals to cross onto the highway. Rather, the study sought to learn whether it was possible to improve crossing success and lower the barrier of the highway by diverting, guiding and channeling wildlife, large and small, to new and/or improved structures. In the process, wildlife – vehicle collisions may be reduced, and wildlife populations and habitat restoration may benefit.

This study was undertaken by the Biosphere Network of the Thousand Islands Frontenac Arch Biosphere Reserve. The Biosphere Network as consultant worked with the supporting steering committee of the Algonquin to Adirondack Conservation Association during the different aspects of the work. The work was done in collaboration  with the Eastern Ontario Model Forest, the Leeds County Stewardship Council, and St. Lawrence Islands National Park - Parks Canada. All map work was completed by the Eastern Ontario Model Forest, and was adapted from work completed by the Eastern Ontario Heritage Working Group.

The project was funded by grants from the Trillium Foundation to the Algonquin to Adirondack Conservation Association; and in funding to the Biosphere Network by the Environment Canada Habitat Stewardship Program.

The Study Area:

A 46.9 km stretch from the west edge of Leeds County to the sound barrier wall at Long Beach. This is not the entire width of the Frontenac Arch, but is in the core of that area. Both time and funding precluded a study of the entire width of the Arch. The entire length was walked, and underpass structures and highway segments were located with GPS, and scored. The scoring system was derived from information in numerous research articles related to wildlife studies about highways, previously conducted around the world. Notes captured observations and findings, including locations and species of road kills, are elaborated on in the complete study report. Improvement potentials and recommendations for underpass structures are presented there as well.

The study was divided into three sections.
Part I discusses the valuation of the Highway 401 in terms of

1. the value of existing highway underpass structures as passages for mammals and herptiles; and
2. ii) the value of visibly different segments of the Highway 401 related to their porosity (how much the highway is a barrier for wildlife crossings).

            Part II is subdivided into two sections. Part II a deals with the complex area of the Gananoque River – 401 Highway intersection, and the immediately surrounding area. The discussion reveals the existence of a corridor effect, and discusses methods and scenarios for improvements. Part II b discusses a related wildlife crossing situation at 401, east of Highway 32.

            Part III discusses conditions along the section of the Gananoque River waterway from north of 401 to the general area of Charleston Lake. Various aspects of the wildlife corridor are reviewed, and problematic areas are highlighted, with improvement scenarios discussed. An overall strategy for conservation related to the corridor effect is discussed.

A sample of study findings:

Funnel Effect.
There is a funnel effect on this landscape, where topography guides animal movements. Steep rock cuts are barriers to crossings, but the ridges themselves are travel routes for wildlife that favours upland habitat. Wildlife crossing points are focused where heights of land at rock cuts come down to roadbed grade level. There is a concentrated potential for wildlife mortality at such areas of the highway.

There would seem to be potential to build overpass structures where some species could cross at some rock cuts, and in fact the topography may lend itself to that. The funnel effect locations would have high potential for new overpass development. Rock cuts, which guide wildlife, would provide initial heights of land where specialized bridging structures could be lofted. Suggested locations are where significant woodlands and wetlands cross the highway, at segments valuated Medium or High, and where further and precise study shows best use of the funnel effect.

Existing Underpass Structures.
Underpass structures are various forms of culverts and river and road bridges. These are used by many species of wildlife, particularly by smaller species. Habitat restoration at the north and south approaches to underpass structures is as important as the improvement of the structures themselves. In the original construction of the roadbed, proper drainage was a primary consideration. The ditch work has done as much to isolate the habitats separated by the highway as the highway itself. Restoration work will need to be done on MTO land and on the land that abuts the highway at each chosen location to connect habitat at opposite sides of the highway. Landowners too will need to be engaged for that work, and to ensure that the broader property of significance is protected or managed through the future years. Improvement of as many of these structures and adjacent habitat as possible is important, as these will collectively vastly improve porosity of the highway and at the same time reduce road kill significantly.

Median Barrier.
The concrete median barrier in the study area is in the western 6.7 km of the study area. It causes significant rates of wildlife mortality. Road kill rates are especially elevated in smaller mammals. MTO has determined that the barrier is necessary because of the close proximity of the east and west bound lanes and the need to prevent head-on collisions.  At the same time, there is risk for accidents as motorists swerve to avoid animals trapped on the highway by the barrier. A suggested alteration to the median construct is to replace some portions of the solid barrier with an open post and rail structure, as at the Cataraqui River on 401 Highway. The precise locations for the more porous barrier would be chosen through closer study of critical habitats for small mammals and herptiles. However, the most effective effort would be improvements to underpass structures and associated habitat restoration, as discussed in the paragraph above.

Fencing.
Proper fencing must be part of any corridor restoration, not to prevent animal movements and highway crossings, but to guide them to improved structures and locations. The existing fencing is entirely inadequate, and does nothing to inhibit movements of animals of any size. Proper fencing is commercially available and used by highways departments throughout North America. It must be installed to compliment other crossing measures.

Future Work:

There are elements of this study that can be applied to other highways. The models to assess highway porosity and their relationship to connectivity on the landscape, for example, can be used on similar multi-lane highways, for both new and redevelopment construction. Future work in this region would be:

            ~ To plan and work strategically to restore corridors, habitat and improve existing underpass structures.

            ~ To ground truth habitats that in GIS work appear as core areas and corridor routes, and evaluate these habitats for importance to wildlife as corridors as well as breeding/survival habitats.

            ~ To engage landowners in strategies for conservation of habitats that lie upon the corridor routes.

            ~ To engage highway and transportation departments in structuring for improved porosity, including improvements to existing structures as well as the potential of building new overpass structures.

            ~ To attract funds to do the improvements.

           
The Algonquin to Adirondack corridor is a continental scale landscape connector, but in fine view, lies across the river, on islands and to and through appropriate terrain on the US and Canadian sides of that river. Here indeed is an international challenge—to diminish the barriers to wildlife movements throughout the Algonquin to Adirondack landbridge.

Download here for the results of the Highway 401 Porosity Study.