Date: 4/8/25 10:02 pm From: Doctor Science <science.dr...> Subject: Re: [JERSEYBI] Corvus species overlaps in central NJ
How close was the carcass to the car lane? When I've seen AmCrows feeding on roadkill, it's always been ones that are *very* close to the roadway, in the shoulder (where there is one) or the verge, or on/over the white line itself. My assumption has been that the crows are there because it's too dangerous for vultures, which make slow, lumbering take-offs. Crows can just leap into the air when cars get too close--and even so, I've seen dead, smashed crows near such feeding sites. It's a risky choice!
- Mary Ellen
On 4/7/2025 6:03 PM, Mike Lenker wrote: > 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 > > List Guidelines: > https://lists.princeton.edu/cgi-bin/wa?A2=ind2107&L=JERSEYBI&P=R685&X=OE8E22FEF3A2B10DFE5 > List help: <jerseybi-request...> > List archives: https://lists.princeton.edu/cgi-bin/wa?A0=jerseybi > NJ Bird Records Committee: www.njbrc.com >
