The breeding distribution of Common Raven has exploded across MD over the past 10-15-20 years. Attached are distribution maps from the first (1996) and second (2010) Breeding Bird Atlases (two black and white images) and also the Common Raven map from the Third Breeding Bird Atlas (multi-color), which just completed data collection on Dec. 31st.
As you can see, the observation pins on the color map showing current distribution are so dense in the Baltimore-Washington region that they obscure the map place names! And yet Common Raven was totally absent as a breeding bird in the Baltimore-Washington region in the first (data collected 1983-1987) and second (data collected 2002-2006) Atlases.
Ravens have even started to colonize the Eastern Shore, around Chestertown in Kent County, for example. This was formerly unthinkable.
It’s really been a remarkable expansion, which the late Rick Blom (editor of one of the early editions of the Nat Geo Field Guide) predicted when he first saw a Common Raven flying along the Susquehanna in Cecil County in the 1990s.
We have them almost every time we go out around our house on Loch Raven in northern Baltimore County. I think I first saw them in the Baltimore area when driving the Baltimore Beltway across the Key Bridge circa 2010, maybe earlier. And they nested at Duckett Dam (Rocky Gorge Reservoir) in Prince George’s County circa 2010 and later. That might have been the first documented nest in the DC area. The nest site was visible from I-95 if you happened to be stuck in traffic and could take a good look.
FYI, on the multi-color BBA3 map, the red pins marked with a C indicate a confirmed breeding site, purple with R is a probable breeding site, medium blue with P is a possible breeding site, and O in pale blue is an observation with no breeding recorded. You can visit this interactive map at
https://ebird.org/atlasmddc/map/comrav and zoom in to see more detail for your neighborhood, or zoom out to see the whole state.
Marcia
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Marcia Watson
Phoenix, MD