What's the Difference Between a Raven and a Crow?

American Crow (Image by: DickDaniels, via Wikimedia Commons, CC BY-SA 3.0)

Many people see a rather large black bird and assume the bird is a raven. Or a crow. Some people assume ravens and crows are the same type of bird. That's understandable, since they look similar at first glance. To make things more confusing, both birds belong to the crow (corvus) family, and any member of that family can be called a crow. That means a raven could be called a crow, but not all crows could be called ravens. What's the difference between a raven and a crow?


Technically speaking, a crow is any bird from the genus, corvus. However, the word "crow" is most often used to refer to just a few specific species. In North America, it usually refers to either the American Crow or the Northwestern Crow. In Europe, it usually refers to the Carrion Crow or the Hooded Crow. Most crows are black in color (however, the Hooded Crow is mostly grey), have a wingspan of around three feet, and are around 18-21 inches in length, depending on the particular species. They eat almost anything - fruit, nuts, carrion, eggs, small rodents, amphibians, scraps from garbage, etc. They tend to hang out near humans so they can scavenge. Crows are very intelligent, and are often regarded as some of the world's smartest animals. They make many vocalizations, and are great mimics.

Common Raven (Image by: David Hofmann, via Wikimedia Commons, CC BY 2.0)

Most sources will tell you that one of the main differences is that ravens are larger than crows. While this is usually true, it isn't a fool-proof way of telling the birds apart. The Common Raven is generally between 22 and 30 inches in length, and as mentioned above, crows can be as large as 21 inches. Therefore,a large crow can easily be mistaken for a small raven (and vice versa) if you only go by size.

Even so, there are other physical differences you can look for. A raven's feathers are shinier and usually "fluffier" (or appear fuller) than a crow's. A raven's bill is larger and curved closer to the end than that of a crow. Ravens have a slight point in their tail which gives it a wedge shape, while a crow's tail is more rounded. Ravens also look a bit different in flight. They have longer, thinner wings and are likely to be seen soaring. If you see a black bird doing a somersault in the air, you're looking at a raven! If you hear its call, you can usually figure out which bird it is - a crow has a distinctive "caw caw" sound, and a raven's call is deeper and more of a croak. Ravens are also less social than crows and are more likely to live in less populated areas or in parks, though they can adapt to most environments.

Ravens and crows aren't completely different, however. The similarities in appearance are obvious, and both birds have demonstrated problem-solving skills in laboratory experiments and in the wild, which puts them both toward the top of the avian intelligence ladder. They eat similar diets - they are both opportunistic omnivores, even though ravens seem to prefer carrion a little more than crows. Of course, one of the main things crows and ravens have in common is that they are both awesome and fascinating birds.

Elephant Poachers are Poisoning Vultures

Rueppell's vulture (Photo by: Hans Hillewaert, via Wikimedia Commons, CC BY-SA 3.0)

Here's another entry for the "reasons why people suck" list.

Elephant poaching has been a problem for a quite some time. Poachers kill these majestic beasts primarily to harvest their ivory tusks to sell illegally. The tusks are made into trinkets, which are seen as status symbols in some parts of the world. Elephant hides are also sometimes taken and sold. Rhinos are being poached as well for their horns, which can be carved into objects or used in traditional medicine. Even though trade of ivory is restricted, demand through illegal ivory networks is rising, and poaching is getting worse.

Poaching these animals is bad enough. However, to make things even worse, elephant and rhino poachers are also killing off vultures. Why are they harming these birds? As most people know, vultures eat dead animals. When something as large as an elephant dies, you'll find many vultures gathering near the carcass to partake of the feast. Police and wildlife officials use this behavior to their advantage. They can follow the vultures to track the poachers.

Unfortunately, these poachers have no respect for lives other than their own (if they did, they wouldn't be poaching), and the vultures threaten their "businesses." To try to kill off the informers, the criminals poison the elephant and rhino carcasses. When the vultures, who are just looking for something to eat, consume the meat, they die. The poachers hope to eliminate the vultures in the areas they operate. Sadly, these lawbreakers don’t seem to realize that vultures travel huge distances to find food, so it’s impossible to get rid of vultures in a particular zone. Or maybe they do realize it and are fine with playing a huge part in the extinction of these birds.

This past July, there was a poisoning incident in Namibia that killed 600 vultures. This just adds to the list of problems vultures in Africa have been facing for decades. Thanks to habitat loss, predator poisoning from farmers, and the use of veterinary drugs that are deadly to birds, vulture populations in West Africa have declined by 42% in the last 30 years. One species, the Rueppell’s vulture, has been hit particularly hard, with an 85% decline.

New Direction for the Blog...

I live! I also want to do something with this blog again. I originally started it about a year and a half ago as "Animal Fact of the Day." For about a month or so, I was pretty good about posting some sort of animal fact almost every day. However, I soon learned that I had bitten off more than I could chew. Trying to come up with a new and exciting animal fact to write about every day became quite a challenge. I was stressing out over keeping things interesting and fun, and about keeping the content coming. It became a "something I still have to get done today" chore as opposed to something I enjoyed doing. I was starting to burn out, and fast. It didn't help that I went back to work and also started taking classes, both of which took up a lot of my time.

In any case, I've recently started to miss writing about animals. However, the idea of trying to come up with daily animals facts again is still as daunting as ever. Therefore, I've decided to give the blog a bit of a makeover. Animals will still be the main topic, of course. However, posts will cover animal facts, news, and just random basic information. They also won't come every day. I'm thinking maybe one or two posts per week, on average. I could have a particular productive week in which I become inspired to write more, but I doubt that will be a regular occurrence.

Anyway, say goodbye to "Animal Fact of the Day," and hello to "Animal Facts, News, and Info."

Watch Out for Zombie Bees

Maciej Czyżewski, CC-BY-SA-3.0,2.5,2.0,1.0, via Wikimedia Commons

"Zombie bees" (aka zombees) are showing up is some parts of the United States. Don't worry, they aren't coming after our brains. The poor critters are infested with a parasite.

Apocephalus borealis, a fly known as the "scuttle fly" or "zombie fly", is the culprit. This insect has been known to infect bumble bees and paper wasps in the past, but now it is also using honey bees as hosts. The adult fly lands on the bee's back and injects the eggs into the abdomen. The eggs hatch, and the maggots eat the bee from the inside while they grow. Once a bee is infected, it will abandon the hive at night and fly around erratically in movements reminiscent of a zombie. This goes on until the bee dies and the maggots crawl out to pupate. 

As of October 3, 2012, the problem is primarily in California, where the bees were first discovered in 2008. However, confirmed cases of infection have also been confirmed in Oregon and Washington State, and as far east as South Dakota. The flies themselves have been found scattered across the United States and Canada, all the way to the east coast.    

The honey bee has been a victim of unexplained die-offs around the world in recent years. Bees are also susceptible to a variety of other parasites, bacteria, fungi, and viruses. The zombie fly is yet another threat to populations of one of our most important pollinators.

You can find updates on the spread of the infection at ZomBee Watch.

Some Pets Can Contract the West Nile Virus

Electron Micrograph of West Nile Virus (CDC Image, via Wikimedia Commons, PD-USGov)

2012 was a record year for the West Nile virus. We already know that this virus is zoonotic, which means it can pass from animals to humans, and from humans to animals. What does this mean for our furry, feathered, and scaly friends?

West Nile Virus in Cats and Dogs
There are two ways a dog or cat could possibly be exposed to this disease. He may be bitten by an infected mosquito, or may decide to snack on an infected prey animal such as a mouse. That being said, dog and cat owners can relax a bit. The West Nile virus doesn't seem to cause much harm to our two most popular pets. In an experiment, cats and dogs were intentionally infected with the virus (yeah, I'm not crazy about that either). The dogs and some of the cats didn't show any symptoms, and the rest of the cats experienced only mild symptoms such as lethargy and a slight fever. (You can read the report here, but I recommend stopping after the abstract if you're a cat and/or dog lover).

Even though WNV probably won't harm the health of your cat or dog, if you notice any suspicious symptoms, contact your veterinarian. He or she can provide supportive care for your pet if necessary.

Reptiles and Amphibians
Studies have been done with iguanas, garter snakes, bullfrogs, and turtles (specifically, red-eared sliders). In one experiment, the iguanas, snakes, and bullfrogs became infected, but none exhibited symptoms. In a different study involving only garter snakes, 4 of 9 snakes died. Young crocodiles and alligators seem to be the most susceptible to WNV - there have been outbreaks of the disease among wild alligators in multiple states. Also, there have been transmission studies that strongly suggest the virus can pass directly from an infected alligator to tankmates. Symptoms to watch out for are "star gazing" and mouth lesions.

Horses
There's good news and bad news for horse owners. First, the bad news is that horses are susceptible to the WNV. Most horses that get bitten do not get sick, however, those that do get sick show symptoms of encephalitis such as loss of appetite, depression, weakness, muscle twitching, paralysis, convulsions, or coma. The good news is that vaccines are available for horses. Vaccination is obviously your best protection, but other ways to reduce your horse's risk include: keep your horse inside during peak mosquito times, set up fans in the stable to help keep mosquitoes out, eliminate standing water, and check the property frequently for dead birds. If you do find a dead bird, call your local health department, and of course, never touch a dead wild animal with your bare hands.

Small Mammals (Pocket Pets)
Many small mammals have been experimentally infected with WNV. Mice, rats, and hamsters developed clinical signs (some severe). Guinea pigs and rabbits, however, did not become sick.

West Nile Virus in Pet Birds
Wild birds are the primary hosts of the West Nile virus. Crows, jays, thrushes, chickadees, and raptors are among the most affected. The virus has been reported in approximately 300 species of birds, so as one might guess, pet birds can become infected as well. Fortunately for parrots and their owners, psittacines seem to have at least some resistance. However, there have been a few cases in parrots such as macaws, cockatoos, conures, budgies, and cockatiels, so no bird is 100% safe. Some birds with the virus experience weight loss, weakness, fluffed feathers, or neurological symptoms such as paralysis, lack of coordination, circling, or seizures. Other birds experience no symptoms at all. For some, the only symptom is sudden death.

Officially, there is no vaccine available for birds,* and you should never use insect repellents on or near your bird due to the fact that birds are much more sensitive to chemicals than we humans are. So, how do you protect your birds? If your birds are indoors, they are pretty well protected as long as you keep your doors and windows closed (or screened) to avoid letting mosquitoes into the house. If your birds are in an outdoor aviary, you may wish to consider bringing them inside during peak mosquito times. If that's not possible, you can try using mosquito netting, and of course, make sure there's no standing water nearby.

As always, if you notice any symptoms, contact your veterinarian.

*Some zoos are using the equine WNV vaccine on their outdoor birds, and are experiencing some success with it. However, the vaccine has not been officially approved for birds as of yet.

Those Scary-looking Anglerfish With the Big Teeth are Female

Public Domain Image (PD-1923) via Wikimedia Commons

This deep sea fish may be familiar due to its appearance in Finding Nemo, as well as its appearance on almost every list of "the world's ugliest animals." However, you're not likely to see one in person. Seeing a male deep sea anglerfish would be even less likely, and if you did see one, you probably wouldn't know it. When it comes to the humpback anglerfish (the kind in the above drawing) and "sea devils," the fishing lure and huge mouth full of teeth belong only to the females.

You may wonder where the males are. Well, you'll usually find them connected to the body of the female. When a male angler becomes sexually mature, his digestive system stops working. His options are then to either die of starvation, or find a female and join with her as a parasite. Neither option is a great one for the poor male. When he finds a female, he bites her, and then his mouth dissolves into her body. Their blood vessels merge, and over time, the male's organs are absorbed until the only things left of him are his gonads. The female can then use them when she wants to spawn, and she can end up with up to six "males" attached to her.

As far as the lure and giant teeth: the female uses her lure like a human angler would - to draw her prey (other fish) close enough for her to snatch with those teeth. The teeth are angled inward to help keep the prey from escaping, and her jaw and body are pliable enough to allow her to eat prey twice her size.

(Apologies for the lack of updates lately. My classes are starting to take up most of my time. I'll post again soon... I promise!)

The Blue-Footed Booby Has Multipurpose Feet

Photo Credit: Maros (via Wikimedia Commons)

The Blue-Footed Booby is a bird with feet that are made for more than just walking. Like most seabirds, his feet are webbed and work as paddles for swimming and diving. On the downside, the web shape makes the bird clumsy as he walks on land, which is where his funny name came from ("booby" comes from the Spanish word "bobo," which means "stupid" or "clown"). Even so, the male blue-footed booby is quite proud of his feet, and he uses them to help attract a mate.

As one may guess from this bird's name, the feet are often blue in color. However, the color actually ranges from bright green to dull blue. When the male is ready to attract a female, he will perform a courtship dance full of struts and high steps - all moves meant to show off his feet. Studies have shown that females tend to prefer bright green, and that the color is dependent on the amount of carotenoids in the diet. Therefore, it seems the color is an indicator of the booby's nutritional condition (and suitability as a mate). 

The blue-footed booby has one more important use for those feet. These birds do not have brood patches (a bare patch of skin on the bird's belly for sitting on the eggs), so they use their feet to keep the eggs warm. The parents will continue using their feet to keep the babies warm even after hatching, as the chicks are unable to control their own temperatures for about the first month of life.