Crows – bird brainiacs! Crows, magpies and jays are all in the Family Corvidae. They are intelligent and are said to know you, your neighborhood, your dogs, anyone who feeds them and will even remember if you have done them wrong and will tell others about it, but if you are nice and provide them with food they might bring you trinkets to show their appreciation. WOW!! And you ask how do we know this? Scientists have been studying them for years. One guy at Cornell University in New York has been studying them for over 35 years…that is a lot of data!
In this area we have the American or common crow, the fish crow and the common raven. The American crow is all black, length 17.5″, wingspan 39″ and weight about 1 lb. The fish crow is very similar, you can tell the difference by the sound of its call – more nasal cah-cah or cah ah vs. the American crow caw caw. The common raven is larger, length 24″, wingspan 53″ and weight 2.6 lbs. The raven is usually seen with just one other raven or in small groups. It very rarely mixes with crows. The common call is a deep croak, brronk.
Crows are very social, often they will get together and “mob” hawks and owls to keep them away. Crows are territorial, but on cold winter nights you will see them forming large, communal roosts. I have seen them in West Hartford at dusk when they are settling in for the night. Estimates are that 19,000 crows roost in that area and although that sounds like a large number, some roosts have seen 50,000 crows gather together. Scientists aren’t exactly sure why this happens, they think it is one method of protecting themselves from predators. The same roost locations have been used for decades or even longer. One in New York has been used for over 125 years. Crows form these roosts in late fall and use them until early spring when they return to their breeding territories. Especially in urban areas these roosts are messy and noisy so people use various techniques to keep them from establishing roosts in their area.
Crows are omnivores, 75% of their diet is vegetable food, grains, seeds, fruits and nuts. Also eat small mammals, eggs, insects, young birds, spiders, millipedes, crustaceans, frogs and reptiles. Sometimes crows will drop mollusks, like whelks, on rocks or walnuts on roads to open them. They have been observed to watch the light to see when it turns red to time the dropping of the walnut!
The American crow seems to flourish around humans. They live in a wide variety of semi-open habitats from farms to open fields to clearings in the woods. They are often found around garbage dumps.
Crows and ravens brain is more like primates (apes, gorillas, chimpanzees…humans). They can analyze and process information and they have flexible behavior. Experiments have shown they can recognize humans after only one experience. While wearing a caveman mask a researcher went out and captured and banded crows. Whole gangs of crows followed and dive bombed the “caveman”. Over the years the caveman would return and the crows would still attack the “evil caveman”. They must have communicated this to other crows, since 10 years later they would still attack the caveman! It appears crows need only one experience to form a memory of who can, and who cannot, be trusted.
If a crow dies, other crows will gather around it as if they are having a funeral. They will not touch the dead crow. No one knows for sure, but it appears they might just be gathering to communicate information about some danger.
The American crow generally has 4-6 eggs. Both parents feed the young and 80% of them will have “helpers”. The helpers are older siblings that bring mom or dad food, feed younger siblings directly and help protect the nest. A family unit includes mom and dad, several kids and can include up to 15 birds. In addition to brothers and sisters, the extended family might include nephews or nieces, or half-brothers and sisters. Males and females look the same, one way to tell the difference is by doing blood work.
Crows are so amazing…they can even make tools. The Caledonian crow from the South Pacific can craft J-shaped hooks from twigs and use them to extract insects from tiny crevices. A BBC video showed a crow able to solve an eight step puzzle to gain access to a larger stick so that it could use the stick to get food out of a box…incredible! So much is known, but there is so much more to learn. Maybe one day you will help to solve the mysteries involving crows!