12 August 2024
On Friday I wrote about a swarm of dragonflies. Today it’s a swarm of swallows.
On 31 July my sister watched more than two dozen tree swallows swarm over her yard in Tidewater Virginia. They were feasting on flying bugs for about 20 minutes, and then they were gone.
After they finish breeding, tree swallows (Tachycineta bicolor) gather in ever-growing flocks in July and August and begin their southward migration. In transit they seek out swarms of insects that may include true flies (Diptera), dragonflies and damselflies (Odonata).
Peak tree swallow migration occurs in early to mid-fall. I was at Cape Cod on 1 October 2017 when I witnessed a huge flock at West Dennis Beach. Abundant bugs attracted the tree swallows; abundant swallows attracted a falcon who captured one in his talons (top right of photo below).
On 6 October 2021, Mike of Mike’s Nature Connection witnessed a similar flock on Cape Cod.
If you live in the Mississippi or Atlantic flyways, or at their wintering grounds in Florida or Louisiana, there’s still time to see swarms of tree swallows. Watch their annual movements in this weekly abundance animation from eBird.
See this map for yourself at eBird Status and Trends > Tree Swallow > Weekly Abundance.
I was just asking someone where all the tree swallows had gone that were so prevalent at North Park and Moraine SP.