Do birds have sense of smell?
One of my readers contacted me via email today to ask the question: “Do birds have a sense of smell?” It’s a really good question and one I’d never really given much thought to.
Thanks to Bev for this question. (You are the first to use my contact form – see the sidebar.)
Do birds have a sense of smell?
The short answer is yes, they do.
The long answer is more complicated.
The upper mandible (beak) is pierced by the nostrils. Usually the nostrils are near the base of the bill. Relatively few birds are known to use the sense of smell in their search for food; indeed in most species the sense of smell seems to be poorly developed. (Quoted from the book “Birds: their life, their ways, their world” published by the Reader’s Digest in 1979)
So they can smell but most species do not rely on this sense much at all.
Birds that have a good sense of smell
There are always exceptions to the rule!
Some birds do have a highly developed sense of smell. The New Zealand Kiwi, for example, has nostril placed near the tip of the bill and this enables it to smell its food as it probes the earth and leaf litter. The kiwi has a double whammy; not only does it have very poor eyesight, it is also mostly nocturnal in its habits. Having a fine sense of smell is a definite bonus if you are a Kiwi (the bird, not the people of New Zealand!).
I also remember a sequence on “The Life of Birds” videos featuring David Attenborough where he hides a piece of rotten meat under the leaf litter deep in a rainforest. Within minutes the local Turkey Vultures had found the hidden meat, even though they had been several kilometres away.
Likewise some seabirds are able to smell great distances:
For example, fulmars can smell fish oils from up to 25 kilometres (15 miles) downwind, so when these oils form a slick on the sea surface as a result predatory fish and mammals attacking shoals of fish and squid underwater, the fulmar are quickly at the scene to forage for food. Other sea birds can smell a pheromone that fish give off when stressed. (British Garden Birds website)
Conclusion:
Birds do have a sense of smell, but most rarely use this sense. Some species, however, rely heavily on their sense of smell for their survival.
Acknowledgment:
Thanks again to Bev for this very interesting question.
Laurie left this comment on the Birding-Aus forum:
Yes, the pelagic birds that magically turn up when the shark liver is cast overboard aren’t using their eyes to detect the “bait”.
Avians use the surface pheromone from the glands on the edges of the rictus and “preen” gland at the base of the tail to paint “nuptual gifts” for mate-mate bonding and for nest area marking during “displacement activity.” (The glands swell up during these periods.) It is unfortunate that you are using such an obsolete reference. Indeed, obsolete texts and obsolete ornithologists/ethologists STILL teach “displacement activity” and “mating dances” instead of “surface pheromone marking behavior” and “chromatographic pheromone sensing behavior” respectively. Odd that nobody keeps up, huh?
The necessity for heavier than air flight restricts carrying too much baggage: essentials only. No need for shore birds to detect forest fires (or blundering cigar-smoking twits in ornithology blinds) so why carry the equipment? After all, rocky shores, oceans, and beaches never burn, do they?
Thanks for taking the time and trouble to add to the discussion, B. Nicholson. I was very aware of the obsolete nature of the quote I used but that was all I could find in my small library of bird books at the time.
The original question was a simple request: “Do birds have a sense of smell?” I gave a simple answer that would be sufficient in answering that question for the non-professional, and probably 99% of the readers of this blog. I have no professional qualifications as an ornithologist and that is not the intention of this blog. I just intend to share – as best I can with my limited knowledge – my bird observations, photographs and experiences.
Thank you for adding a more scientifically sound and accurate explanation in answer to the question.
Carol sent me this email on the topic:
Hi Trevor,
I agree with what you’ve written. It’s also the case that most bird-pollinated flowers don’t have much of a scent, but attract birds by their colour and shape. Flowers with a fragrance are usually insect-pollinated.
Cheers
Carol
Carol’s simple error can be corrected as follows: It’s also the case that most bird-pollinated flowers don’t have much of a scent THAT HUMAN BEINGS DETECT, but attract birds by their color, shape, OR SEMIOCHEMICAL SCENT THAT HUMANS FAIL TO DETECT. Flowers with a fragrance THAT HUMAN BEINGS CAN DETECT are usually insect-pollinated (BECAUSE HUMAN OLFACTION AND INSECT SEMIOCHEMICAL DETECTION OVERLAP).
It is easy to be both hopelessly anthropocentric and anti-scientific as Carol demonstrates. People do not salivate when we detect the scent of a particular flower, but to the insect or bird that pollinates that specific flower, the flower’s odor means to them “dinner is served!” even if the odor humans detect is merely “floral” or unappetizing in the extreme. Anthropocentric presumptions about animal perception need to be tested from refutable hypotheses.
Your comments are interesting, B. Nicholson. When I wrote my original email to Trevor I hadn’t read your other posts on this page. I’d be interested in references and/or finding out which bird species have been shown to use pheromone marking and sensing behaviour.
By the way, anyone who knows me would be able to tell you that I am anything but “anthropocentric and anti-scientific”!
David sent me these comments via email:
David Attenborough dramatically demonstrated in his Life of Birds that Black Vultures have a well developed sense of smell – for rotten decomposing meat. He buried it in the midst of the jungle and within 15 minutes Black Vultures homed in on it and proceeded to eat it. However the other New World Vultures that do not, it seems, have a sense of smell know all about their rivals’ ability and watch them and follow their movements!
Some years ago at the IOC’s researchers were able to demonstrate that homing pigeons can use their sense of smell of their neighbourhood to find their way home. Since then there has been no further news although anatomically there is no reason why birds can’t. The olfactory organs are well developed.
David Robertson
Adelaide
i was wondering what colour flowers are birds most attracted to? and if they can see colours or not. thanks
Thanks for your question Emilie – it is an interesting one indeed.
Yes birds can see colours – in fact, they can see colours far more intensely than humans. Scientists have only recently discovered the vast range of colours that birds can see, and most are completely beyond what humans can see or imagine. For a good discussion on this topic go here:
http://www.csulb.edu/labs/bcl/elab/avian%20vision_intro.pdf
As far as what colour flowers birds are most attracted to, there is no simple answer. In my very limited understanding of the topic, birds are attracted more to the ultraviolet patterns on flowers rather than the colour that we see in our limited range of perception.
Hi Trevor,
We have an Indian Ringneck with a great sense of smell.When we have something he likes in the kitchen(out of sight). We believe he can smell it, as he starts screaming for a taste.
Maurice
Well, B. Nicholson is, er, “forthright”, but it is true that we do hear a lot of human-biased interpretation in many exlanations offered as being scientific. The eye-like designs so prominant on the wings of some species of moths (such as Caligo sp.) are eye-like to human interpretation; “and therefore startling to would-be predators”==maybe; maybe not. And the AOU (American Ornithologists’ Union) decides finally on its speciation taxonomy by a VOTE; but I never thought science rested much on voting. I think the more we learn, the less we know. It is good that people have finally allowed birds their sense of smell, but we are still going to read all sorts of speculation about how much smell and how much need and whether some birds will “obviously” need a better sense of smell than others.
I’ve always kept a basket under my bird feeder to catch any seeds that dropped. For years I only got the usual birds that came along. On a whim, I added some cockatiel seeds to the basket and suddenly got so many unusual birds flocked to me basket. It was a delightful thing to see. So yes, birds can definitely smell!!