DULUTH, Minn. — Seagulls can sure overcrowd a beach or a beautiful pier. They can block your view - and steal your food - when you're trying to eat a lakeside dinner.

Now they're even causing a ruckus on the National Weather Service radar.

NWS Duluth posted on Facebook Tuesday that they were "curious" about what was lighting up their radar screen on a clear, sunny morning. When they looked into it, they found out that it was a large group of seagulls flying south across Lake Superior.

The NWS said that the density of the birds was about three to six onscreen at a time. Because of the way the radar works, they look like large hail stones, the NWS said, lighting up the display even when they aren't actually covering the whole sky.

Take a look at the post below or click here:

According to a follow-up post by Weather Channel meteorologist Jonathan Erdman, this kind of bright radar appearance can be caused by targets with "stronger horizontal reflectivity returns than vertical returns. Flat targets like gulls."