The Secret World of Crows
Watchers from the Skies
As you walk outside your door, and move around your yard going about your business, there are eyes upon you. Up in the trees numerous pairs of dark eyes follow your every step. Those that watch you know exactly what you look like, and can pick you out in a group of hundreds. They will make a decision whether they like your face or not. And if they don't, they may well began to stalk and harass you. These watchers are from the animal kingdom, but are smart enough to memorize your habits and patterns if they so choose. If you treat them well, they may bring you trinkets of gratitude. However if you mistreat them they will get revenge too. These creatures may even attack you as you pass by. They can also communicate to others of their kind whether you are friend or foe. If you are an enemy they won't forget and forgive. They will even teach their offspring to distrust you as much as they do.
The watchers in the trees are crows, and they're behaviors and ability to learn have been amazing us for hundreds of years. As you observe the secret world of crows, you will be surprised at the unusual things that the normal flock of crows do in their everyday life. They have adapted to human habitation better than almost any other creature. You could even make the case that they have thrived living beside people. In this article we will take a closer look at our feathered neighbors.
Crows and Humans
As people cleared forests and build cities further and further out, they drove off many species which can only thrive in heavily forested areas. Crows on the other hand, prefer open spaces with enough trees to call home. They also have become experts at living with, and profiting off of humans. Crows are omnivores, meaning they will eat fruit, vegetables, meat, and anything tasty they can find in the garbage you leave out for pickup. Numerous flocks have even learned when the garbage pickup schedules are. When they find an item like stale bread which is a little hard, crows have been seen dipping or dropping the item into a puddle to soften it up. Some crows will use twigs and small sticks as tools to dig or spear insects burrowed in bark.
Crows have no problem co-habituating with people. They have become very accustomed to our habits, and are experts at acquiring food in busy cities. Our avian neighbors also love the little shiny trinkets we inadvertently leave for them. Recently a story came to light that a eight year old girl began leaving food for the local crows. It turn the crows started leaving her a few of their prized possessions from their secret stash, such as buttons, baubles, and small metal pieces. One crow apparently decided to feed her in return leaving a crab's claw.
A Murder of Crows
Crows typically nest together as a family unit. Often older male offspring will help the parents feed newborns. They have different vocalizations, one loud for the flock at large, and a softer sound for talk among the family. They communicate with other crows to warn of potential predators such as cats, hawks, eagles, or owls. If they spot a predator too close to the flock, they will begin mobbing it, meaning they will divebomb, chastise, and harass the potential hunter until it leaves the area. They will also mob people if they feel threatened by them. Crows are very aggressive during the daytime going after owls who are trying to rest before a night of hunting. The idea is to drive the owl father away, so that when it begins it's hunt, it is nowhere near the sleeping, vulnerable crows.
When roosting together, crows will groom each other, picking out parasites from other crows which is normally only seem in primates. They also will indulge in a extremely odd behavior to seems to serve a similar purpose. Crows will find an anthill, and spread out amongst the ants. They will crush an ant in the beaks, and rub the acid that the ant produces on their feathers to drive off parasites. Ants that climb onto the crows will also eat the small parasites that the crows can't reach. Groups of crows will also lay flat on the ground to get some sun, and warm themselves up, especially after a cold spell.
Researchers at the University of Washington devised a test where they captured and tagged crows while wearing a mask over their head. The idea was to see if the crows they tagged would recognize them when they walked in public wearing the mask. Others also wearing different masks also walked around the campus. The crows ignored the researchers in the other masks, but when a person in the familiar mask walked around the crows became vocally aggressive and began mobbing him.
Not only did the specific birds remember, but they communicated to others in the flock that this was a bad person, and they joined in mobbing him. Even more interesting is that as the crows had offspring they taught them to be wary of the masked person as well. This feature gives them a communal memory which lasts far beyond the lifetime of a single bird.
A large group of birds can be referred to as a murder of crows, or simply as a flock of crows. Throughout the centuries, crows along with their relatives ravens, have been associated with death and dying. Which is interesting in that crows seem to mourn their dead. Individual birds will watch over old, ill birds, and when a crow is dead a large group will land around it for a minute or two, and then silently fly off. The intelligence of crows seems to be at a very high level in the animal world, and scientists are occasionally announcing incredible new behaviors that they have observed in the wild, or under controlled conditions. It will be interesting to see how crows adapt in the next decades to an ever-changing world.