Forest Co-op Boreal Wetlands & Waterbirds Project
An old adage circulates in science circles: no control, no conclusion. What does this have to do with forest management? Ontario’s legislation provides that working landscapes should not differ significantly, in ecological aspects, from those landscapes that result from natural disturbances. This policy is similar to a null hypothesis; inability to reject it implies the policy objective is met. Thus, the Forest Co-op Wetlands & Waterbirds Project contrasts managed and reference landscapes to test the outcome of policy.
The Area of the Undertaking (AOU) in Ontario is home to many waterbirds, including species at risk such as rusty blackbirds, yellow rails, and least bitterns. Where timber harvest has largely replaced wildfire as the major agent of landscape change, its effects on these species are not well known; waterbirds are not counted well by standard surveys. The project assembles existing waterbird surveys, to test whether and where the policy objective to emulate natural disturbance is met. The extent of coverage by some surveys into the roadless tracts of the Far North provides for data from reference landscapes where timber management is not the major agent of forest renewal.
Data obtained derive from US Fish and Wildlife Service fixed-wing surveys, the Ontario Breeding Bird Atlas, Canadian Wildlife Service helicopter surveys, and roadside Breeding Bird Surveys to model habitat occupancy under natural and human-induced disturbance. What some surveys provide in spatial and temporal coverage, they lack in species coverage, and vice versa. The project is also testing to what extent the distribution and abundance of species that are most readily detected in extensive aerial surveys can be used to judge the same attributes of species more readily detected by intensive, but spatially restricted, ground surveys.
Early results indicate that even the distributions of ducks with low detectability in some surveys can be predicted reasonably well from the distribution of that species, or others, better detected in other surveys. Occupancy models used to test for the effect of timber management, while statistically holding other environmental variation constant across the AOU and the Far North, are providing the first insights to the extent to which these species are differentially impacted by timber management and wildfire. Effects of human-induced change vary among species, survey types and methods of analysis, and the science team is exploring whether and how to reduce complex results to simple diagnostic indicators for purposes of effectiveness monitoring. The next phase of the research will be to extend these
analyses to explore how well the distributions of other waterbirds, in other datasets, can be predicted by knowledge of the distribution of ducks.