It is interesting to see a study of impacts to migratory birds in this region that does not cite work by the lab groups of professors Hannon, Cassidy-St.Clair, and Bayne, all being full Biology professors at Uof Alberta. They have produced a lot of excellent work that empirically defines impacts to birds from a number of impact sources and at various spatial scales and that would allow detailed impacts modelling over large areas. The expert opinion idea presented here gives further detailed ideas fofr future field work by students of these excellent reserach labs. For example it would be interesting to compare the results of this expert opinion overview with the empiriacal data from the UofAlberta field research labs to see if the conclusions are similar. If so perhaps expert opinion could be useful in future to help direct research questions. Given the abundant available effects monitoring results through UofAlberta, I do not see good reason to substitute opinion in the place of the real observations data for the purpose of management planning.