Ravens and crows are relatives, and show the family resemblance enough to confuse many people. The raven is the big brother – the size of a large hawk, with a wingspan of over four feet. These are birds that have captured the human imagination in dark ways; throughout history they have been regarded as pests and as evil birds that should be destroyed whenever possible.
This bias is perhaps a hold-over from more superstitious times; there are innumerable tales of ravens in witchcraft and the supernatural. In reality these are intelligent, long-lived birds with complex languages and social customs – they are adaptable, playful and a most interesting part of the Island’s natural history. Ravens are not only larger than crows (Corvus brachyrynchos), their roughly-feathered heads and necks also contrast with the much more abundant crow.
Ravens like heavily-forested areas, but are also often seen along the coast. They build large nests in trees which the pair will use for many years if undisturbed. Ravens may live for several decades, and are often found in small groups (families) which share care of the young.
The Raven Year:
Ravens are year-round residents; they begin nest improvement in midwinter. By March three to six eggs have been laid and the incubation period begins. While the female incubates the eggs, her partner can be seen foraging alone and bringing food back for her. This early start to the year means that eggs and young of later nesting birds can be available – ravens, like crows, are efficient nest-predators. By June the young are fledged and can be seen practicing their flying and language skills; young ravens are real talkers. It takes two to three years for full maturity to develop, so a raven family group can have individuals with a variety of ages. All through this time the young are learning to hunt, scavenge and in general become full members of raven society.
Ravens are great scavengers, cleaning up road kill and any other dead meat that they encounter – and they survey a large territory several times a day, looking for the unfortunate. They are also efficient predators, taking other birds up to duck-size, small mammals, reptiles and amphibians. Their keen eye-sight and flying ability makes them particularly efficient as mouse-catchers – they will quarter a field like a hunting hawk, swooping down on an unwary mouse from hundreds of yards away. They are omnivorous when they have to be, but prefer a meat-based diet when they can get it, and preferably dead meat (carrion) since that is less trouble.
Part of the delight in having ravens around is in watching their acrobatic, playful flight maneuvers. They do stall turns, inverted flight, steep dives with folded wings – obviously joyful flyers. An even greater pleasure is in listening to their complex calls and trying to figure out what they are saying. Ravens are great mimics – there are many stories of birds that could do an excellent train-whistle, or car-horn sound. Except when hunting or carrying food they are seldom silent for long, commenting on anything or anyone they see. The young have teen-age voices, while adults have much deeper tones.
Raven Habitat Management:
Since ravens have traditionally been regarded as enemies, there is relatively little information available on positive management steps. They need a reasonably undisturbed nesting environment so old-growth forest is preferred, although there are reports of nests being used for years in hedgerows on busy farms. They need protection from gunners.
In particular, supplementary feeding during the critical nesting period can be beneficial in lean years. Any spare carcasses from trappers can be hung in trees (keeping them away from foxes and coyotes) to provide a fascinating feeding station. Spare eggs or food scraps will also be appreciated. Try this as a spring experiment – set out a few eggs where a raven doing a fly-past will see them. Chances are he will land nearby, do a few jumping-jacks over them to be sure that this is not a trap, then carry them off one by one to the nest site. After the young are fledged such supplementary feeding is not necessary, but any dead meat will still be appreciated by this great scavenger!