In high temperatures, a dip in cool water is often a welcome change for four-legged friends. A quick romp in the riverbed, but then—pain, swelling, bruising, and itching. During black fly season, this ...

The insects, identified as a type of black fly common to the region’s riverine foothills, are appearing in numbers far higher ...

A surge of biting black flies is sweeping across the San Gabriel Valley foothills — and officials warn the infestation could ...