A new report from the National Academies of Sciences, Environmental Impacts of Wind-Energy Projects, is in pre-publication. As summarized in the press release, the study examined onshore projects only, and concluded that wind projects will have a measurable impact on CO2 emissions by 2020 but will not reduce sulfur dioxide or nitrogen oxide levels.
The report seems to haver on the effects on vertebrate populations—birds and bats:
… the committee saw no evidence that fatalities from existing wind facilities are causing measurable changes in bird populations in the United States. A possible exception is deaths among birds of prey, such as eagles and hawks, near Altamont Pass, Calif.—a facility with older, smaller turbines that appear more apt to kill such birds than newer turbines are.
Too little information is available to reliably predict how proposed new wind projects in the mid-Atlantic highlands would affect bird populations…