Date: 4/7/25 3:04 pm
From: Mike Lenker <0000070123d7500d-dmarc-request...>
Subject: Re: [JERSEYBI] Corvus species overlaps in central NJ
During last years winter (2023-2024) while driving home from work on
Middletown Lincroft Road in Middletown, there was a relatively new roadkill
deer on the side of the road. There were two Ravens feeding on it. I
turned around and went by slow a couple times to get a better look. There
were no TV or BV on the scene yet. They flew off when I stopped to try to
get a picture. So they will feed on roadkill.
This a fairly busy two lane road, approaching a traffic light at Rt.
520/Newman Springs Rd. and not far from exit 109 for the Garden State
Parkway. The actual location was right in front of a day care and less than
100 yards from a shopping center.

Mike


-----Original Message-----
From: Doctor Science
Sent: Monday, April 07, 2025 12:53 AM
To: <JERSEYBI...>
Subject: [JERSEYBI] Corvus species overlaps in central NJ

Last Wednesday I was sitting on my back deck in northern Hopewell
Township (Mercer County), when in the course of 15 minutes I saw & heard
*all three* Corvus species: American Crow, Fish Crow, Common Raven. It
was a very educational compare & contrast!

But it got me wondering: how do these three species sort out living
together these days? I say "these days" because Fish Crows are expanding
their range inland, so having so much overlap with AMCR is relatively
new. And CORA has only returned to NJ in numbers in recent decades as
farming has declined and the tendency of farmers to shoot black birds as
varmints has faded.

I know that in my yard and surrounding properties the AMCRs are
permanent residents, I hear them most days. Ravens & Fish Crows are
occasional visitors, but shouldn't this be nesting season, with birds
sticking close to home? It may be these are young, unmated birds, out
looking for trouble while the older birds are nesting--it takes Corvus
2-3 years to reach sexual maturity, and may be even longer before they
first breed.

So, fellow central Jersey birders, what kind of ecological separation
have you been seeing between our three Corvus species? Are they
feeding/flying in similar areas, but nesting in different ones? I'm
talking especially about parts of the state that aren't close to any
large river or the ocean, nor the highlands.

Poking around the scientific literature, there are some indications that
CORA prefers rocks, cliffs, buildings, bridges; AMCR prefers evergreens;
FICR deciduous trees; but those are statistical preferences, not
hard-and-fast rules. As for food, they're all opportunistic omnivores, I
don't know how much separation there is around here. Though I haven't
seen CORA feeding on roadkill, a common practice for AMCR. It's possible
Ravens think roadkill is just too dangerous. I haven't noticed any of
them joining vultures at big carrion-eating parties when a deer dies in
a field.

- Mary Ellen Curtin

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