Though crows possess the required machinery to sniff various scents, the extent of their sense of smell is currently unknown.
Which is why it is hard to conclude whether crows rely on their sense of smell to find food.
But, recent research suggest that:
You may be wondering:
Why a Crow’s Sense Of Smell Is So Dubious?
Because of a common misconception that “Birds cannot smell at all”.
It started in 1820 when the infamous ornithologist – John James Audubon set out to prove that Turkey vultures found food only through their exceptional eyesight.
First, he stuffed a deerskin with grass and put it in an open field.
The vulture responded by tearing apart the dummy.
However, when he hid a decaying carcass beneath grass cover, the vulture didn’t swoop down.
Consequently, John concluded that vultures don’t smell the rotting flesh.
This set a tradition among ornithologists who avoided research on birds’ ability to smell.
Soon, the notion became a wide-held belief that birds lacked the ability to smell. And so,
Nobody imagined crows to smell at all, much less sniff around to locate food.
In the 1930s, some engineers injected ethyl mercaptan vapors into a gas pipeline to pinpoint the leakage but they ended up finding several vultures hovering near the drainage site.
The incident revealed how vultures could find carcasses by smelling mercaptan – a gas released from decaying matter.
This discovery led several ornithologists to further validate the sense of smell in vultures.
Still, most scientists firmly believed that regular birds could not detect scents.
Eventually, they discovered that all birds had a distinct olfactory bulb – an exclusive section of the brain that can decode different odor particles.
However, birds have limited brain space.
Therefore, it’s hardly surprising that the avian olfactory bulb is significantly smaller compared to mammals of relative size, thereby, limiting their sense of smell.
However, it’s fair to conclude that:
Crows have a sense of smell as they have a microscopic olfactory bulb in their brains.
But If Crows Can Smell, Can They Find Their Food By Sniffing Around?
Most likely not.
Now, Crows’ inability to find food by mere scent is consistent with the fact that crows are not the first to arrive at most food sources.
But then, there is an ancient saying:
“If you wish to find a dead body amid woods, look for a murder of crows hovering above.”
So, how do crows locate dead bodies without smelling?
Does that mean crows can smell meat?
Let’s find out
Do Crows Smell Meat?
They do, but not enough to find meat solely by catching a whiff.
Now, there is no precise study that demonstrates a common crow’s ability to smell meat or the extent of this ability.
In one related study, scientists took juvenile ravens (five males and 3 females) as test subjects in a series of four different experiments.
The results showed that ravens could locate raw minced fish hidden beneath at least 2.5cm gravel or as less as 1g of meat under 1.5cm gravel.
Since the only way for ravens to find food was through their sense of smell, therefore, Ornithologists concluded that:
Corvids can smell meat.
Again, this does not show how far can a crow smell a piece of meat.
One way to determine the extent of a crow’s smelling capacity is by looking at the size of its olfactory bulb, with a larger olfactory bulb hosting more nerve receptors and therefore, a better ability to distinguish various smells.
Crows’ microscopic olfactory bulbs suggest a limited ability to distinguish scents.
Perhaps, crows can only smell meat and a few other scents.
That explains crows’ niche as carrion-eating birds.
Surely, crow DNA contains nearly all olfactory receptor proteins.
But it appears that evolution has led to reduced expression of more than 60% of these olfactory genes.
It seems that crows didn’t really need a keen sense of smell to thrive through the ages.
Meanwhile, Kiwis smell their way to find food.
Therefore, it’s not surprising that Kiwis have more than 80% of functional olfactory genes.
Anyways, you may be thinking that if crows don’t find food by smell, then:
How Do Crows Find Food?
Technically, by stumbling across it.
Now, this may involve the following:
Method | Explanation |
Opportunity/Chance | Like all organisms, crows cannot ignore food and potential mates. And so, if a crow happens to find an unattended nest, chicks, or other food items. It will make sure to devour it. |
Exploratory Nature | Birds are extremely cautious yet curious creatures. Therefore, if a crow feels safe enough, it will visit all kinds of unknown sites for potential food sources. |
Following Others | Crows often follow other crows to either forage together, or to find new sources of food. |
Crows can understand other birds. Therefore, if too many birds are excited over food. Then, crows can follow them to the source. | |
Revisiting Food Sources | If a place presents food every single day, then crows will make sure to keep revisiting that site.
This explains why crows regularly visit bird feeders, dumpsters, and compost sites. This is also true for human birders who are often followed by crows. |
If a human often feeds crows, then he will be followed by crows. | |
Stealing | Sometimes crows often wait for predators to catch their prey. Then, they outwit the tired predator and steal its food. |
Secret Stash | On finding a large enough food source, crows eat to their fill and cache what they cannot eat in secret places t devour later. |
Using new Techniques | New Caledonian Crows have been reported to scoop out grubs by using twigs and grass leaves. They can even dip their bills in holes to take out worms. |
Crows often rip open trash cans to take out food. | |
In Queensland, crows were reported to flip over Toxic Cane Toad, only to stab its thin skin to eat non-toxic innards. | |
In Japan and later in California, crows were reported to place nuts on the road at red light signals only to open them by vehicles. | |
Wild hooded crows in Israel use bread crumbs as fish bait to capture seafood. | |
Invitation by Other Crows | If crows find a food source large enough that they cannot devour alone. Then, they make crow calls to invite other crows. |
These methods represent a crow’s impeccable ability to find food without using much of the sense of smell.
However, as crows stash extra food, it seems odd when they call out other crows to feast together.
So, you may be wondering:
Do Crows Call To Each Other When They Find Food?
They do, but only if the food source is large enough to share.
That means that if a crow finds a little food, it will eat it and stash the leftovers.
However, if a crow finds the food large enough to share it will call its peers.
In fact, this feast of crows is precisely why farmers started to erect scarecrows amid fields.
But I doubt if this is how George R.R. Martin found inspiration for his book title “The Feast of Crows”.
Anyways,
Crows are notorious for their bullying and seemingly greedy habits.
It feels odd when a crow becomes generous enough to call out other crows before digging in his newly found food source.
This leads me to my next point
Why Would Crows Share Food At All?
Ornithologists suggest the following reasons for crows to invite other crows for food:
1. Protection
Therefore, eating with other crows seems beneficial for the crow who ends up finding a large enough source of food.
2. Reducing Competition
Since more crows can devour a large food source and reduce competition from other animal species, calling other crows is advantageous for crow species.
3. Care
Crows appear to be quite family-oriented with elder siblings staying longer in the nests to help raise their younger siblings.
Crows calling other crows for food may also be a sign of caring.
4. Survival as a Group
Crows are quite the average birds.
However, their survival lies in their ability to act as a group.
Sharing food ensures that crows thrive further.
That said, it must be noted that crows’ survival as a group also resides in their ability to eat everything from seeds, fruits, insects, and worms to eggs, animals, and even carrion.
Since crows eat almost everything, one wonders if they eat everything because it all tastes the same.
This leads me to my next point
Do Crows Taste Food?
They do, but their sense of taste is less sensitive than most animals.
You see, crows have only about 100 taste buds located at the roof and the base of their beaks.
Furthermore, a crows tongue has small hair-like extensions surrounding protein-digesting enzymes or papillae that help in shoving food down the throat.
In contrast, an average human has about 9000-10000 taste buds on his tongue.
A crows tongue is much less sensitive to taste than humans.
But even with only 100 taste buds, crows seem to have a keen sense of bitterness, sweetness, sourness as well as saltiness.
This is manifested by crows spitting out Monarch Caterpillars as these worms taste bitter.
Crows can also taste the spice but they lack gene VR1, therefore, crows don’t experience the heat that comes with eating spice.
Furthermore, even birds with much fewer taste buds can distinguish taste.
For instance, Hummingbirds have only 40-60 taste buds but they can tell sugary water apart from regular water.
Besides a huge number of tastebuds does not make animals exceptionally picky either.
For example, a cow has as many as 25000 tastebuds that do not make it a picky eater but do help it in determining the absence of phytotoxins.
It seems that a high number of taste buds has more to do with evolutionary benefits than the characteristic to become picky.
For Instance, Geese have 400 tastebuds to ensure their survival by testing the salinity of the water.
But fewer taste buds can make a specie less picky.
This explains why chickens with 24 taste buds and pigeons with 37 taste buds are less picky eaters that eat almost everything.
Are Crows Truly Less Picky Eaters?
Well, that comes down to how you observe them.
You see, if given a choice, crows prefer meat over vegetables and fatty nuts over regular nuts.
It can be said that crows are picky, only if they have a choice to do so.
Wrapping Up
Crows do possess a sense of smell as well as taste.
However, the sensitivity and extent of these senses may be limited compared to their visual and hearing capacities.
It may be that crows don’t need to sniff much to find food.
They even call out to other crows if they find a huge source of food.
That said, Crows seem to be able to smell meat.