American Crow

Corvus brachyrhynchos
Corvidae

Becoming more frequent at Salter Grove
Both crows and jays have bristles covering nostril which places them in the same family
A familiar silhouette
But wait, here's a leucistic form!
And even a piebald version!
Eating fish does not make it a Fish Crow
Clamming is not an easy living
Primary (finger) feathers round out the wing shape
Worn primary feathers will be replaced one-by-one when breeding is done
Tail feathers are even at tip
Tail is fan-like when spread
American Crow (top) is smaller than Common Raven
About same size as Cooper's hawk
Mobbing a Red-tailed Hawk
A clutch contains 3 to 9 eggs
Nestlings demanding and getting food
Both parents feed nestlings
Nearly adult-sized fledgling still begging
This parent likely to quit soon

There is no evidence that American Crows breed at Salter Grove but they are observed year-round, usually in small groups of three to four individuals.  Their raucous calls can be heard throughout the park and help to distinguish them from Fish Crows, which have a different sounding call and tend to visit the park during the warmer months.  Occasionally, murders of more than 30 crows fly overhead during the winter and probably consist of birds that share a communal roost. 

The American Crow is found throughout North America south to northern Mexico.  Crows can live in pretty much any open habitat with tall trees, especially conifers and large oaks in which they like to nest.  They are rarely solitary, usually traveling in extended family groups.  Offspring often stay with their parents for a year or two to help rear siblings before setting out on their own.

Crows are omnivorous, feeding on acorns, carrion, invertebrates, nuts and scraps of food left by humans.  During low tide at Salter Grove, they forage on exposed mudflats and the seaweed-covered rocky islets of Rock Island.  They are also hunters of small animals like mice and frogs.

Depending on the cultural tradition, both ancient and modern, crows are considered to be omens that portend either something good or something bad is about to happen.  However, there is consensus that they are highly intelligent.   As common as they are, they have not been very well-studied because any successful attempt to capture and mark individuals works only once.

Susceptibility to the West Nile virus has caused the crow population to decline by 45% since 1999, the year that the virus first arrived in the U.S.  Crows cannot transmit the mosquito-borne virus directly to humans but affected crows would indicate the presence of the disease in an area.

Since there is no vaccine for the West Nile virus yet, preventative measures would involve diligent use of insect repellent and protective clothing to avoid bites by infected mosquitoes.