Here's how it works. Adult male mosquitoes and blackflies are vegetarians, as are many male midges. If they eat anything at all, it's likely to be nectar or plant juices. But their female counterparts aren't so easily satisfied. And so it is.
Blood is critical to the proper development of their eggs.
No blood meal, no eggs. And without eggs, there won't be future generations of blackflies, midges, or mosquitoes. In the next few weeks, this frantic imperative will be brought home with special force, as hordes of paddlers take to northern lakes and rivers in search of respite and recreation. While all but a few city-dwellers and suburbanites will have encountered mosquitoes before, many folks new to backcountry waterways will be meeting blackflies and biting midges for the first time. To most, it's going to be a memorable encounter.