Black-eared kite wing tagging project – Hong Kong

Background / Introduction

The black kite is the most common diurnal raptor in Hong Kong, and a species that regularly turns up at the KFBG rescue centre. KFBG is the first organisation in Hong Kong to introduce wing tagging as a method for carrying out post-release monitoring of black kites, with the first wing tags being attached to a kite in July 2023.

During the past 25 years of rescue work, KFBG has received 423 kites, of which 255 have been successfully released after their rescue and treatment: a commendable release rate by international wildlife rehabilitation standards of 60%. However, as is common with many centres, post-release survival data is lacking.

Wing tagging is an effective and safe method for ecologists and conservationists to retrieve data about animal movements, migration, nesting/breeding patterns, roosting localities, growth rates, and territoriality. Rescue centres involved in wildlife rehabilitation and native release may consider this technique a useful method to monitor post-release survival and behaviour.

How can wing tags help to improve rehabilitation success?

• Post-release survival data can be obtained for black kites within Hong Kong, or further afield and can help release locality decisions and give proof of captive care success;
• Statistical analysis of certain health issues on admission or certain aspects of rehabilitation can contribute to post-release survival, especially when there is an opportunity to recapture a released bird and carry out a health check;
• Continuous improvement of rehabilitation practices as a result of observing wild behaviour can help future kites in care;
• Raised awareness among members of the community can help provide feedback and opportunities for citizen science, and in turn provide information that might help rehabilitators and how they care for kites in captivity.

Wing-tagging procedures

1. Health check and wing tag application

Rehabilitation and release requirements are assessed for every bird according to the current KFBG guidelines. The rehabilitation and veterinary teams must be satisfied that kites are injury-free, disease-free and fit to survive in the wild prior to release. All kites arriving at KFBG undergo initial triage and stabilisation. Once stable, they are placed under anaesthetic, during which the following is carried out by a veterinarian:

• A full physical examination, including age estimation;
• Radiographs (X-rays) and blood testing;
• Microchip implantation;
• Wing tag fitting on both wings.

During their stay at the rescue centre, kites are also fitted with a leg band according to British Trust for Ornithology standards.

2. Wing tag design and application

KFBG wing tags have been designed specifically for the size and shape of black kites. They are made of green, UV-proof, soft, flexible, lightweight plastic canvas. The white lettering is also UV-proof, meaning it will not be degraded by continuous exposure to sunlight.

The wing tags will carry the following information:

1. The side on the outside/upper side of the wing
   1. QR code linked to a fillable form for sighting data collection
   2. HKMMXX (HK: Hong Kong, MM: Milvus migrans, XX: unique number)
2. The side on the inside/underside of the wing
   1. Same QR code as above
   2. MMXX (MM: Milvus migrans, XX: unique number)

The tag number and QR code may not be visible at height. However, a photo taken by a member of the public may show the code, allowing the photographer to connect to the online form and fill in the sighting details.

For further  details about the  KFBG Black Kite Wing Tagging Project, please click here

“Please provide details of your sightings of wing-tagged kites”

Your feedback is essential to our project, please help by filling the form below if you spot a kite with a wing tag. You will be greatly assisting our project to determine where the birds go and how long they live.

RESULTS at April 2025 - one and a half years have passed and the project is yielding good post-release resighting data.

Since the project began in July 2023, the tag design has been simplified significantly.

The initial version included a QR code, but the new version features a larger, more visible number.

As the project has gained more attention, the public has become aware that they need to report bird sightings through the KFBG website, making the QR code unnecessary.

To date, thirteen kites are flying around Hong Kong with tags fitted (numbers: 06, 61, 91, 51, 63, 90, 30, 46, 69, 37, 93, 34, and "JC"). One kite has been recaptured, and one kite was found deceased by a member of the public. Below are some details about these birds: