More than 60 per cent of Canada’s flying insects have disappeared from a single site over the last four decades, starting in the late 1970s, and the effects can be seen among the birds that rely upon them for sustenance, according to a newly peer-reviewed study published in the Proceedings of the National Academy of Sciences (PNAS). Tree swallows in Ontario’s Long Point Bird Observatory are getting smaller and producing fewer offspring due to the decrease in insect numbers.