Your data on MRCVSonline
The nature of the services provided by Vision Media means that we might obtain certain information about you.
Please read our Data Protection and Privacy Policy for details.

In addition, (with your consent) some parts of our website may store a 'cookie' in your browser for the purposes of
functionality or performance monitoring.
Click here to manage your settings.
If you would like to forward this story on to a friend, simply fill in the form below and click send.

Your friend's email:
Your email:
Your name:
 
 
Send Cancel

Rare half-male, half-female bird captured on film
Green plumages indicate a female green honeycreeper, and blue plumages usually appear on males.
Bilateral gynandromorphism is extremely rare in birds.

A zoologist has captured footage of a rare half-female, half-male bird while on holiday in Columbia, after it was spotted by an amateur ornithologist.

The wild green honeycreeper had a distinct and unique plumage which was half green and half blue. Green plumages indicate a female green honeycreeper, and blue plumages usually appear on males.

This means that the bird is a rare example of a bilateral gynandromorph, meaning that one side of it has male characteristics and the other has female.

The green honeycreeper had male plumage on its right side, with female plumage on its left. It was observed to remain in the area for at least 21 months.

Its behaviour appeared to match that of other wild green honeycreepers, although it did wait until the other birds had left before feeding on food left out by the property owners.

The phenomenon is extremely rare in birds, which means that the images captured by Professor Hamish Spencer are particularly significant. It is only the second recorded example of gynandromorphism in a green honeycreeper in more than 100 years.

Bilateral gynandromorphism is usually identified in species with strong sexual dimorphism, including butterflies, crustaceans, lizards and rodents.

It occurs when an error during female cell division for producing an egg is followed by double-fertilisation by two sperm.

The images of the bird, which Prof Spencer called "arguably the best of a wild bilateral gynandromorphic bird of any species ever", have supported a report on the findings. It has contributed to scientists’ understanding of the phenomenon, including the discovery that female plumage was possible on either side.

Prof Spencer, from the Department of Zoology at the University of Otago, said: "Many birdwatchers could go their whole lives and not see a bilateral gynandromorph in any species of bird. The phenomenon is extremely rare in birds, I know of no examples from New Zealand ever.

"It is very striking, I was very privileged to see it,"

The new study is published in the Journal of Field Ornithology.

Image © Shutterstock

Become a member or log in to add this story to your CPD history

Webinar to explore AMR in vet dentistry

News Story 1
 The WSAVA has invited veterinary professionals to a webinar on responsible antibiotic usage in dentistry.

On 19 November 2025, at 1am, Dr J Scott Weese and Dr Brooke Niemiec will share the latest advice for antimicrobial use. They will present research on oral bacterology, and explain how attendees can choose appropriate antibiotics.

The session will cover pre-, intra- and post-operative guidelines, with recommendations for various pathologies.

The webinar is designed to support veterinary professionals to make informed decisions and tackle antimicrobial resistance.

Attendees can register here

Click here for more...
News Shorts
Bluetongue reaches Wales for first time in 2025

The Animal and Plant Health Agency (APHA) has revealed that bluetongue has been confirmed in Wales for the first time in 2025.

In their latest statistics, APHA records a total of 109 cases of BTV-3 or BTV-8 in Great Britain in the 2025-2026 vector season.

The total number of BTV-3 cases in Great Britain this season is 107. This includes 103 cases within the England restricted zone and four cases in Wales.

There has also been two cases of BTV-8, which were both in Cornwall.

As a result of the cases in Wales, a Temporary Control Zone (TCZ) is enforced in Monmouthshire. Animals can move freely under general license within the England Restricted Zone, however animals with suspected bluetongue must stay on their holding.

All premises testing positive for blue tongue can be viewed on this map.