Do Birds Have Smell? Yes, But It Varies by Species

Yes, birds do have a sense of smell, although it is often underestimated and varies significantly across species. For decades, the common misconception was that birds were anosmic—unable to detect odors—but modern ornithological research has firmly debunked this myth. The question do birds have smell is now answered with a resounding yes, supported by both anatomical evidence and behavioral studies. In fact, certain bird species such as kiwis, turkey vultures, and seabirds like petrels and albatrosses possess highly developed olfactory systems that play a crucial role in survival, from locating food to navigating vast oceanic distances.

The Biology Behind Avian Olfaction

Birds possess olfactory bulbs in their brains, the size and complexity of which correlate directly with their ability to detect and process smells. While many songbirds have relatively small olfactory bulbs, suggesting a limited reliance on smell, other species exhibit remarkably large ones. For example, the kiwi, a flightless bird native to New Zealand, has the largest olfactory bulb-to-brain ratio of any bird. This adaptation allows it to probe deep into soil and leaf litter, using its keen sense of smell to locate earthworms and insects—its primary food sources—often without relying on sight.

In seabirds such as tubenoses (Procellariiformes), including albatrosses and shearwaters, the olfactory system is equally advanced. These birds have tubular nostrils on their beaks and use scent to detect dimethyl sulfide (DMS), a compound released by phytoplankton when consumed by krill. By following DMS plumes over thousands of miles, they can locate productive feeding areas across the open ocean. This ability answers the long-tail query: how do seabirds find food in the ocean?—a key reason why understanding avian olfaction matters in ecological and conservation contexts.

Historical Misconceptions About Bird Smell

The belief that birds lack a sense of smell dates back to the early 20th century, largely influenced by flawed experiments and oversimplified assumptions. Early researchers, focusing primarily on pigeons and passerines (perching birds), observed minimal behavioral responses to odors and concluded that birds in general were anosmic. This assumption persisted despite anecdotal reports from naturalists who noted behaviors suggesting otherwise—such as turkey vultures circling over hidden carcasses long before they were visible.

It wasn't until the 1960s and 70s, with the pioneering work of biologist Bernice Wenzel and later neuroanatomist Stacia S. Hoffman, that the scientific community began reevaluating avian olfaction. Using comparative brain mapping techniques, they demonstrated that certain bird lineages had evolved sophisticated olfactory capabilities independently. This shift in understanding highlights how bias in early research can delay scientific progress—a cautionary tale relevant to current debates about animal cognition and sensory perception.

Species That Rely Heavily on Smell

• Kiwi (Apteryx spp.): Nocturnal and ground-dwelling, kiwis have nostrils at the tip of their long beaks, allowing them to sniff out prey while probing the forest floor.
• Turkey Vulture (Cathartes aura): Known for locating carrion solely by scent, even beneath dense forest canopies where visual cues are limited.
• Storm-Petrels and Shearwaters: Use odor trails to navigate and find food patches across featureless oceans.
• Homining Pigeons: Though not primarily olfactory navigators, some studies suggest they may use environmental scents as part of a multi-modal navigation system.

How Smell Influences Bird Behavior

Olfaction in birds extends beyond foraging—it influences social interactions, mate selection, and predator avoidance. Recent studies on European starlings and dark-eyed juncos show that birds can distinguish between individuals based on scent, possibly through preen oil secretions. These chemical signals may convey information about health, diet, or genetic compatibility, playing a subtle but important role in reproductive success.

In colonial seabirds, smell helps chicks identify their parents among hundreds of similar-looking adults. Experiments with Leach’s storm-petrel chicks demonstrated that they responded more strongly to the scent of their own parents than to unfamiliar adults. This ability reduces misdirected parental care and increases breeding efficiency—an evolutionary advantage in crowded nesting colonies.

Predator detection is another critical function. Research on black-legged kittiwakes showed that they avoided nesting areas treated with the scent of mammalian predators, indicating an innate ability to recognize danger through smell alone. This ties into broader ecological questions such as can birds sense danger through smell?—a topic gaining interest in wildlife management and conservation planning.

Practical Implications for Birdwatchers and Researchers

Understanding avian olfaction can enhance field observation techniques. For instance, birders tracking turkey vultures should know these birds often arrive at carcasses before scavengers relying solely on sight. Observing sudden aggregations of vultures circling over intact forest may indicate an unseen food source below—detectable only through smell.

Researchers studying seabirds increasingly incorporate olfactory cues into experimental designs. Deploying scent baits (e.g., fish oil slicks) during surveys improves detection rates for species like shearwaters that are otherwise difficult to observe at sea. Similarly, conservationists protecting nesting colonies now consider odor contamination—such as human scent left behind during monitoring—as a potential stressor affecting chick survival.

Bird Species	Olfactory Bulb Size	Primary Use of Smell	Notable Behavior
Kiwi	Very Large	Foraging in soil	Nostrils at beak tip; probes deeply into ground
Turkey Vulture	Large	Locating carrion	Finds hidden carcasses under canopy
Albatross	Large	Oceanic navigation & foraging	Follows DMS plumes to feeding zones
House Sparrow	Small	Limited; possible mate recognition	Relies mostly on vision and sound
European Starling	Moderate	Social and mate assessment	Distinguishes individual scents via preen oil

Debunking Common Myths About Bird Senses

One widespread myth is that all birds navigate exclusively by sight and magnetic fields. While vision and magnetoreception are vital, especially in migratory species, dismissing olfaction overlooks a growing body of evidence. Another misconception is that because most birds don’t have external noses like mammals, they must lack smell. However, birds’ nostrils (nares) are simply less conspicuous, often located near the base of the beak or concealed within feathering.

A third false belief is that domesticated birds, such as chickens or parrots, cannot smell. While their olfactory abilities may be less acute than those of wild specialists, studies confirm that even chickens respond to airborne pathogens and spoiled food through olfactory cues—important for disease avoidance and flock health.

Regional and Ecological Variations in Olfactory Use

The extent to which birds use smell depends heavily on ecological niche. In tropical rainforests, where dense vegetation limits visibility, birds like the oilbird (Steatornis caripensis) rely on echolocation and smell to navigate caves and locate fruit. Oilbirds, nocturnal frugivores, emit sharp clicks and use olfactory cues to identify ripe figs and palms—an adaptation rarely seen in other birds.

In contrast, open-habitat species such as larks and pipits, which depend on visual scanning for insects, show reduced olfactory development. This ecological correlation underscores the principle of sensory trade-offs: energy invested in one sense (e.g., vision) may reduce investment in another (e.g., smell).

Geographic location also plays a role. Seabird populations in nutrient-rich upwelling zones, such as off the coast of Peru or Namibia, may rely less on long-distance olfactory navigation due to higher prey density and visibility. Conversely, in vast, oligotrophic (nutrient-poor) regions like the South Pacific, efficient scent-based foraging becomes essential for survival.

How Scientists Study Bird Smell

Studying avian olfaction presents unique challenges. Unlike mammals, birds cannot be easily trained in laboratory odor discrimination tasks. Instead, researchers use a combination of methods:

• Neuroanatomy: Measuring olfactory bulb size relative to total brain volume provides indirect evidence of olfactory capacity.
• Behavioral Experiments: Presenting birds with scented vs. unscented food or nesting materials to observe preference or avoidance.
• Chemical Analysis: Identifying volatile compounds in preen oils or environmental samples that birds might detect.
• Tracking Studies: Using GPS loggers on seabirds to analyze flight paths in relation to oceanic scent plumes.

These interdisciplinary approaches continue to refine our understanding of how birds perceive their world—not just through songs and colors, but also through invisible chemical signals.

Implications for Conservation and Human Interaction

Recognizing that birds can smell has practical consequences. For example, using strongly scented repellents may deter nuisance species from urban areas more effectively than visual deterrents. Conversely, conservation workers should minimize human scent when handling eggs or chicks to avoid triggering abandonment—a phenomenon documented in species like penguins and terns.

In captive breeding programs, ensuring proper ventilation and minimizing exposure to artificial fragrances (e.g., cleaning products) supports bird well-being. Additionally, reintroduction efforts for endangered species like the California condor now account for olfactory cues in habitat selection and foraging training.

Frequently Asked Questions

Can birds smell humans?

Yes, some birds can detect human scent, particularly species with strong olfactory abilities like vultures and certain seabirds. Prolonged human presence near nests may lead to disturbance or abandonment.

Do birds use smell to find their nests?

In some species, especially colonial seabirds, smell helps individuals locate their burrows or chicks among thousands. However, most birds rely more on visual and auditory cues.

Are there birds that can’t smell?

All birds have some degree of olfactory capability, but it varies widely. Many passerines have minimal reliance on smell, though they may still detect strong odors like smoke or decay.

Can birds smell food from far away?

Yes, especially scavengers like turkey vultures and marine birds like albatrosses, which can detect food-related chemicals from several kilometers away under favorable wind conditions.

Does pollution affect bird smell?

Emerging research suggests air and water pollutants may interfere with chemical signaling, potentially disrupting foraging, navigation, and social behaviors in sensitive species.

In conclusion, the answer to do birds have smell is unequivocally yes—though the degree and purpose vary dramatically across species. From the kiwi’s earthy foraging to the albatross’s transoceanic scent trails, olfaction is a vital, if underappreciated, component of avian sensory ecology. As research advances, we gain deeper insight into how birds experience their environments, enriching both scientific knowledge and our appreciation of avian diversity.