Are Crows the Smartest Birds in the World?

When you consider the true brainiacs of the animal kingdom it’s usually dolphins, chimpanzees and great apes that come to mind; with the exception of parrots, birds aren’t likely to make most people’s lists. However, research over the past decade is beginning to indicate that crows may not only be the smartest birds, but possibly more intelligent than even chimpanzees.

American crow - Photo by Walter Siegmund

The term “crow” is used to refer to any bird of the 40 or so members of the Corvus genus. Some members of the genus may also be called ravens or jackdaws. Crows can be found throughout most of the world, even introducing themselves to areas where they are not native. Most members of the genus are fairly large birds that are black in color.

Certain species of crows have shown remarkable intelligence not seen elsewhere in birds. New Caledonian crows are known for their tool making. In one test a crow was observed bending a piece of straight wire into a hook to lift a bucket of food from a vertical pipe; it had never been exposed to wire before. These crows also make tools out of grass and sticks to probe for insects in trees, and have even been seen dropping nuts on to busy streets so the heavy cars would crack them. Even more amazing, the crows would then fly down to intersections and only cross into the street with pedestrians to retrieve the nuts safely.

Crows also exhibit complex social behaviors, particularly seen in the common raven. Young ravens tend to make a large fuss when feeding on a carcass in order to attract other juveniles so they can feed in the safety of a group. Adults on the other hand stay whisper quiet when feeding so as not to attract uninvited guests. Like parrots, ravens are capable of mimicking almost any sound they hear, including human speech. They use this ability both to mock and confuse other animals, even mimicking the call of a coyote or wolf to attract them to a carcass that is too thick for the raven to open itself.

Velociraptors Weren’t So Scary

Next to Tyrannosaurus Rex, probably no other dinosaur is as recognizable as the velociraptor. In the 1990 book and subsequent film Jurassic Park the raptors truly were the stars.

Depicted as six foot tall pack hunting lizards with razor sharp teeth and claws, the velociraptors of the movie were about as scary as dinosaurs get. The only problem is that real-life velociraptors didn’t look or act anything like that.

Illustration by Matt Martyniuk

Above is an illustration of what paleontologists believe the velociraptor really looked like. Quill knobs found in fossils prove that it was completely covered in feathers, and the long stiffened tail was likely used for balance. However, feathers or not, the biggest inaccuracy in the film and book was the velociraptor’s size, as in real life it only stood about two feet tall and weighed 30lbs.

Illustration by Matt Martyniuk

However, you can’t totally place the blame on author Michael Crichton. The raptors of the book and movie were based more upon deinonychus, a much larger ancestor of the velociraptor that lived 40 million years earlier and was over 11 feet long. At the time of the book’s writing, some paleontologists believed that the two were more closely related than they actually are.

Of course, the book and movie were both works of fiction and would have been much less entertaining if the main antagonists resembled a pack of angry roadrunners. Besides, as far as we know T-Rex was still pretty scary!

The Black Bear that's White

If you find yourself hiking the woods of coastal British Columbia, Canada there is a very slim chance that you might spot a bear that’s completely white. Although it may look like a small polar bear, what you’d actually be seeing is a Kermode bear, a rare subspecies of black bear.

Most Kermode bears look just like regular black bears. However, in this region and particularly on Princess Royal Island one in every ten Kermode bears is born white. Their stark white appearance against the green rainforest habitat has led to them being referred to by native peoples as “spirit bears”.

The Kermode bear’s white coloring is caused by a recessive gene; they are not albinos and are no more closely related to the polar bear than any other black bear.

Saving the Greater Prairie Chicken in Missouri

Greater prairie chickens, which are closely related to grouse, used to exist in the millions in the Great Plains. It is estimated that hundreds of thousands lived in Missouri alone before the 1930’s. However, when commercial farming took over the region in the early twentieth century the prairie chicken’s habitat was almost completely wiped out. Prairie chickens require large expanses of tallgrass prairie to survive and cannot exist on agricultural land. Today, less than seven percent of Missouri’s tallgrass prairie still exists and there are only about 500 prairie chickens left in the state.

Greater prairie chicken male

A subspecies of the greater prairie chicken known as the heath hen was once extremely common in New England. Easy to hunt and vulnerable to predation by introduced dogs and cats, the heath hen was a staple of colonial life in the region until it was finally driven to extinction on the mainland by 1870. Conservationists in Missouri are determined not to let the same happen to the greater prairie chicken.

In an effort to keep this native bird and its booming call from disappearing forever, a partnership of 20 state agencies called the Missouri Grasslands Coalition is working on a long-term project to restore the habitat of the prairie chicken and bring its numbers back into the thousands. This project has been going on for many years already as it requires overcoming several major obstacles to be successful.

Perhaps the biggest obstacle is the habitat itself. Tallgrass prairie is a unique ecosystem that cannot be used for farming or grazing; this presents a problem in a state like Missouri where 93% of all land is now privately owned. To overcome this, the MGC is working with landowners to provide prairie chicken habitat in exchange for subsidies.

Another issue is maintaining a breeding population. Because of the scarcity of tallgrass prairie, greater prairie chicken flocks only exist on “islands” throughout the Great Plains and the birds rarely migrate more than 10 miles away from where they were born. To establish populations, Missouri Department of Conservation officials are importing birds from Kansas, where they are more numerous, and placing the birds in tallgrass prairie conservation areas.

If you’d like more information about saving the greater prairie chicken, please contact the Missouri Department of Conservation here. 

The Laotian Rock Rat - Living Fossil

Happy Monday, everybody! After a week spent talking about sharks I figured it might be nice to focus on an animal today that most likely won’t ever get a minute on television, despite making a comeback after a vacation of at least a few million years! Meet the Laotian rock rat: living fossil.

Animals and plants that are considered to be living fossils are those that are nearly identical to a species only known from fossilized remains with no other living relatives. Cockroaches and aardvarks are two commonly known animals that are referred to as living fossils. The recently discovered Laotian rock rat may fit this description as well, but there is some debate.

Discovered in Laos in the late 1990’s, the Laotian rock rat was first thought to be so distinct from all living rodents that it was placed in a new family called Laonastidae. However, in 2006 this classification was debated by biologists and it was instead suggested that the Laotian rock rat is a relative of members of the ancient Diatomyidae family which has been extinct for 11 million years. The rat is commonly placed in this family now. If this is indeed the case, the Laotian rock rat would join sixteen other mammals that were once thought to be extinct only to be rediscovered, though none have been thought extinct for nearly this long. This type of occurrence is known as a Lazarus taxon.

The Laotian rock rat appears different from other living rats. Despite the similar appearance and coloring of its body, it has the long and bushy tail of a squirrel. Most are about 15 inches in length with a third of that coming from the tail and a weight of about a pound. These rats have thus far only been found in the Khammouan Province of Laos. Though little is yet known about this newly-discovered species, their limited range and pressure from trapping has led the ICUN to label them as endangered. 

Basking Sharks - The Lazy Predators

As we close out this week, we’d like to focus on a shark that just doesn’t get any respect; the basking shark. Although it’s one of the largest species of fish in the world, the whale shark is larger, so it won’t set any records there. It isn’t a vicious predator either, and despite being as long as a city bus poses absolutely no danger to humans or any large creature of the sea.

The basking shark gets its name from its appearance of relaxing (i.e. basking) in warmer waters near the surface while it feeds; and due to their massive size they are quite hard to miss. Basking sharks are usually 20-35 feet in length and weigh about 4 tons. The largest specimen ever confirmed was over 40 feet long and weighed an estimated 34,000lbs!

Basking shark filter feeding

Although basking sharks are sometimes mistaken for great white sharks, the two could not be more different. Whereas great whites are active hunters, the basking shark is a passive filter feeder. It feeds on zooplankton and small fish simply by swimming around very slowly with its enormous mouth wide open. Prey is snagged by the basking shark’s many sets of gill rakers. During this process, the shark naturally takes in a massive amount of water. However, unlike other filter feeding sharks that can close their mouths and pump this water out manually, the basking shark can only expel water by continuing to swim at its lumbering 3mph pace.

Basking shark head

Basking sharks do migrate throughout the year and can travel thousands of miles in a season. It is assumed that this travel is related to reproduction or following plankton blooms. Due to this migration, at certain times of the year basking sharks may be found in nearly every ocean of the world.

The Thresher - The Shark with a Whip

To see a common thresher shark from the front you may think that it looks a lot like many other sharks. The streamlined, torpedo-shaped body and classic dorsal fin fit the profile perfectly. However, once you see that massive tail the thresher shark is unmistakable.

Pelagic thresher shark - Photo: Discovery

The thresher shark’s massive caudal fin isn’t just for looks, either. When hunting, the thresher will use its tail to slap the water around schools of fish to corral them. There have also been several reports of threshers using their tails like whips to stun or kill prey.

There are three species of thresher sharks. As its name suggests, the common thresher is the most widely distributed species and it is also the largest, reaching lengths of over 20 feet and weights of over 1,000lbs. The pelagic thresher is the smallest at about 10 feet long and less than 200lbs. The third species is the bigeye thresher, which features eyes that can be up to four inches in diameter for hunting in deep waters with little light.

Most thresher sharks prefer open ocean; depending on size and species they feed on a large variety of marine life, but prefer schooling fish such as mackerel and tuna as well as squid. Adult threshers rarely have any natural predators of their own.

Despite their large size and that fearsome tail, threshers pose little or no danger to humans. There has only ever been one reported attack by a thresher shark on a person and just a handful of attacks against boats. All of these attacks we most likely provoked, as the thresher is still highly prized by sport fishermen despite all species being nearly endangered.

Hammerheads - Sharks Apart from the Rest

Next to the infamous great white, the hammerhead is probably the most recognizable shark in the world. The distinctive shape of its head is undeniable, but there are a few other things you may not know about hammerheads that make them uniquely different from other sharks.

Photo: Barry Peters

First off, the hammerhead is not just one species of shark. Though the large Great Hammerhead may be the best known, there are actually nine different species of hammerheads in two separate genera. The two largest species are the great hammerhead and the smooth hammerhead at 20 and 16 feet in length, respectively. Most other varieties are significantly smaller, with the 3 foot long bonnethead shark being the smallest.

Bonnethead shark - Photo: Valerie Everett

Unlike most sharks which are lone hunters, hammerheads usually congregate in schools. Depending upon species and conditions these schools can range from just a few individuals to thousands of sharks in a single location. They primarily hunt for crustaceans and small fish near the ocean floor with the largest varieties preferring to hunt stingrays. All except the largest species’ are considered harmless to humans.

Another interesting characteristic is the way hammerheads reproduce. Unlike most sharks, hammerheads do not lay eggs. Rather, their young are nourished in a yolk sack inside the female. After the yolk as been depleted, these yolk sack structures, which are more akin to leather than to an egg, are laid by the female and the pups are born. Hammerhead shark litters can range from 12-40 pups each depending on species.

So what is up with the shape of that head anyway? Like all sharks, hammerheads have electroreceptor sensory pores called ampullae of Lorenzine that allow them to detect the electrical fields given off by other animals. It is believed that the hammerhead’s wide head allows these pores to be more spread out, thus allowing the hammerhead to detect prey more easily than other sharks. It is also thought that the wide spacing of the eyes gives hammerheads binocular vision, and it is known that great hammerheads will use their heads to pin prey against the ocean floor.

Photo: Su Neko

Sharks from Small to Huge

As I mentioned yesterday, this week is all about the celebration of sharks. And while tiger sharks and great whites may get most of the press, they are just a small part of the 400+ species' of these amazing animals. Today I thought I would show you the two bookends of the Selachimorpha (shark) superorder size-wise; the dwarf lanternshark and the whale shark.


Dwarf lanternshark - Illustration by Tambja

 The dwarf lanternshark is the smallest known shark species in the world. Found only in the southern Caribbean Sea near Venezuela and Colombia, this rare species of dogfish shark reaches a maximum length of  only eight inches and lives about 1,000 feet below the surface.



Whale shark - Photo by Zac Wolf

 On the other side of the spectrum is the massive whale shark; not only the largest shark but also the largest fish species in the world. Whale sharks of up to 41 feet in length have been confirmed, and they can weigh in excess of 79,000 pounds. In other words, they are as long as a city bus and weigh as much as 25 automobiles. Despite their massive size, whale sharks are not vicious killers. They are filter feeders and subsist mainly on a diet of plankton and small fish. They swallow massive quantities of water containing their prey when they feed, expelling the excess liquid through their gills and swallowing the leftover plankton.

Aquatic Cleaning Stations

While there may indeed be a week-long celebration of sharks on a certain network, today I thought I would present you guys with some of the unsung heroes of the marine world, the cleaner fish.

Like any animal, a fish can develop skin problems, become afflicted with parasites and get generally dirty. Without the ability to take care of any of these problems themselves, some fish have developed a mutually beneficial relationship with one another.

Certain species of fish are known as cleaner fish. They provide a service to other fish (even sharks) by removing parasites and dead skin from their bodies and food particles from their mouths. It’s mutually beneficial because the cleaner fish feeds on what it removes while the client fish reaps the health benefits.


A pair of cleaner wrasses go to work on a client

The best known cleaner fish is called the cleaner wrasse. These are small fish identifiable by their horizontal stripes. They congregate at “cleaning stations” near the sea floor in the Indian and Pacific oceans. When approached by client fish at these stations, the cleaner wrasses will go to work on whatever part of the client that needs cleaned, even swimming into their gills and mouths if necessary. Although the client fish are easily capable of eating the tiny wrasses, they recognize the service they provide and do not prey upon them.

Other marine animals that provide a similar service are several types of gobies and cleaner shrimp.