Date: 9/3/17 12:38 pm From: Jim Valimont <valimont49...> Subject: Mob scene at Harrison Hills Park - Allegheny County
Today, I lead a Three Rivers Birding Club outing at Harrison Hills County Park near Natrona Heights. The outing was pretty average with a few migrants, but mostly resident birds until the near the end of the outing. We were walking the road from the Environmental Learning Center toward the large fields when we spotted a large number of birds low in a cherry tree. Most were warblers! When we got close to the tree, we saw that the birds were mobbing a large Black Rat Snake sitting along a horizontal branch. Included in the flock were 1 Blue-winged, 1 Black-and-White, 1 Nashville, 1 Hooded, 3 American Redstart, 2 Cape May, 5 Magnolia, 1 Blackburnian, 1 Chestnut-sided, 1 Black-throated Blue, 2 Black-throated Green, and 1 Canada Warblers. Also mobbing the snake were chickadees (hybrid zone), Tufted titmice, Carolina Wren, and Gray Catbird. We watched this scene from the road for 30-40 minutes. It was amazing! And certainly a great experience for several novice birders in the group, who got to see fall warblers really close.
We ended the day with 50 species, including 15 warbler species, 12 of which were included in this one mob. What an experience! And all at eye level perhaps 20 feet away!