Blackpoll Migration thru Lancaster County

I felt like I was hearing a lot of Blackpoll Warblers earlier than expected this year so I dug thru some data on eBird and found that they are actually right on time. First reports start coming in the first week of May if you look at the average birds reported per hour over all the years that have been entered into the eBird database.

Click to zoom in on the graph.

It looks like we can expect the big push to come in the first week of June. I wonder if that first little bump is due to the excitement of seeing them for the first time, which wears off after a week or so.