Study finds bird masturbation is widespread and evolutionarily old

A neglected animal behavior gets a broader scientific look

A new study highlighted by The Conversation argues that masturbation in birds is neither rare nor merely an abnormal captive behavior. Instead, the authors say it is widespread, evolutionarily old, and relevant to both animal welfare and reproductive biology.

The researchers examined 120 bird species across 22 major groups using scientific literature, online reports, bird-keeping forums, and surveys of bird experts. Their conclusion was that masturbation appears across a broad swath of avian life, in both sexes and across age groups, with a deep evolutionary history that implies the behavior is ancient rather than incidental.

That matters partly because the topic has often been pushed to the margins. In captive settings, especially among parrots and other commonly kept birds, masturbation has frequently been treated as a problem to suppress. The piece says folklore husbandry has often framed it as a sign of stress, illness, or poor environmental conditions, leading some keepers to discourage it through punishment, care changes, drugs, or even surgery.

The study challenges that framing. If the behavior is normal and widespread, treating it as inherently pathological could undermine welfare rather than improve it.

What the researchers found

The survey found more records in males than females, but the behavior was documented in both. The authors also report a link between masturbation and species that mate with multiple partners, which they say is consistent with possible reproductive advantages under intense sperm competition.

In males, one proposed benefit is the removal of older sperm, potentially leaving fresher sperm available for future mating. In females, the authors suggest the behavior may increase sexual arousal and could be linked to reproductive strategies in species where mating competition is strong.

Just as important, the study says masturbation was observed not only in captivity but also in wild birds. That point weakens the common assumption that solo sexual behavior in birds is mostly an artifact of confinement.

Because the work spans multiple bird groups, it does more than collect anecdotes. It begins to place the behavior in an evolutionary framework, asking not whether it exists, but what functions it may serve and how researchers should interpret it.

Why welfare may be the most immediate consequence

The most practical implication may be for animal care. Modern welfare frameworks often emphasize the importance of allowing captive animals to express natural behaviors. If masturbation is one of those behaviors, then efforts to suppress it automatically could conflict with that principle.

The article does not argue that every sexual behavior in captive birds should be ignored. Context still matters. Excessive or self-injurious behavior can signal problems. But the study suggests bird keepers, veterinarians, and welfare specialists should be more careful before assuming masturbation itself is evidence of distress.

That shift would align bird care more closely with broader animal-behavior science, where self-stimulatory sexual behaviors are already documented in many other groups, including primates, tortoises, camels, and porcupines.

Opening a broader research agenda

The work also points to how much remains understudied. Bird behavior has been observed in extraordinary detail across migration, song, mating displays, and cognition, yet this area remained comparatively neglected despite obvious welfare implications and abundant informal reporting.

By assembling evidence across species and settings, the authors create a starting point for more rigorous future work. Researchers can now ask whether the behavior tracks seasonality, social structure, captivity conditions, mating system, or hormonal state. They can also test whether interventions aimed at suppressing it have unintended welfare costs.

• The study reviewed 120 species across 22 major bird groups.
• Masturbation was reported in both sexes and across age groups.
• The authors argue it has a strong evolutionary history and is not just a captive abnormality.
• The findings may prompt changes in husbandry and welfare practice.

The headline may attract attention because of the subject matter, but the underlying issue is serious. When a behavior is widespread, natural, and evolutionarily persistent, science and animal care both benefit from treating it as data first and taboo second.

This article is based on reporting by refractor.io. Read the original article.