DEAR READERS: On occasion, I am struck by what is happening to some animal species we take for granted -- or even view with revulsion. One such animal is the crow.
Crows are members of the Corvidae family, which includes rooks, ravens, jackdaws, jays, magpies and choughs. They are omnivores and scavengers, and often consume carrion, the dead remains of animals (as do vultures, of which there are many species worldwide). As consumers of carrion, crows are winged, flagship icons of recycling, doing more good for this planet than we humans.
Crows are highly intelligent and empathic, with complex social lives. They can use tools, solve puzzles and learn by observing each other. Like their raven cousins, they have been seen playing with wolves.
In some cultures, such as the Anishinaabe, crows and their relatives are revered. But in others, they are feared and reviled. Some regard crows as harbingers of ill fortune or death, or simply as pests to shoot and poison. Beyond the time-honored use of scarecrows, there are many other devices that are now available for humanely deterring crows from raiding crops (see birdsnews.com/how-to-protect-crops-from-crows).
A group of crows is called a murder. There are several explanations for the origin of this term, most based on old folk tales and superstitions. This arguably derogatory term probably refers to the racket they make when collectively mobbing an owl, hawk or other predator: a unified response to danger.
Crows and other carrion-consuming birds provide a public health service by quickly consuming carcasses that could soon rot with proliferating putrefying bacteria -- some of which, like the microbe that causes anthrax, are harmful to humans and other animals. They also help control parasitic diseases that are transmissible to humans and other animals, as well as flies that could also spread disease.
These birds have probably evolved resistance to certain harmful bacteria and their toxins. But crows are not immune to West Nile virus, which decimated the crow population some years ago in Washington, D.C.
In the 1980s, the population of California condors -- a group of vultures whose wingspans can measure nearly 10 feet -- was reduced to only 22 individuals because of poisoning. The condors had fed on remnants of animals that had been field-dressed by hunters (i.e., their internal organs were removed), and the remaining carrion contained bullet fragments made from toxic lead. Thousands of tons of lead shot are left by hunters around the world, poisoning raptors, corvids and other scavengers. The use of lead shot should be prohibited.
Vultures were poisoned in the millions in India after eating the carcasses of cows that had been treated with an anti-inflammatory called diclofenac. The drug may have caused the decline of 95% of vultures of the Gyps genus in Southern Asia before it was banned. In 2013, two veterinary drugs containing diclofenac were approved for use in Spain, alarming the scientific and conservationist communities. Few people know how veterinary drugs used on farmed animals can harm wildlife and the ecosystem at large.
Livestock keepers in some countries will put poison on their animals that have been killed by predators, hoping to kill the predators when they return to feed on the carcass. These retaliations contribute to the demise of vultures and other carrion eaters.
Crows and magpies are now "outsmarting us," according to Netherlands biologist Auke-Florian Hiemstra, by removing rows of sharp metal pins from rooftops and ledges -- installed to repel birds -- and incorporating them into their nests. "We're trying to get rid of birds, (but) the birds are collecting our metal spikes and actually making more birds in these nests," said Hiemstra. "I think it's just a brilliant comeback." (Full story: New York Times, July 13)
We humans have nothing to crow about, considering our responsibility for the climate and extinction crises. We need to learn something from the crows, as well as from ravens and vultures, about cooperative, communal living and recycling/sanitation. In this regard, we should all eat crow!
WEST NILE VIRUS ALERT
Spread by mosquitoes, the West Nile virus is the leading cause of arbovirus disease -- any viral disease spread by insects -- in the continental U.S., according to a recent CDC report. In 2021, 2,911 cases of West Nile virus were reported in the U.S., leading to 2,099 hospitalizations and 227 deaths. That was the most elevated rate of the disease since 2012. (Full story: CNN.com, Aug. 24)
My advice: Use safe insect repellants.
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