During bird migration season, birds from the north fly to the south to survive cold winter. Migration journeys are often risk-laden, sometimes even fatal. Habitat loss and bird-hunting are only a few examples. Here we'd like to introduce one of the hidden deathtraps in our urban environment ── Bird collision.

Bird collision occurs when a bird fails to perceive glass structure as barrier and crashes into it. Window collision can result in bird mortality. But how to judge if a dead bird was killed in collision? Have a look at the surroundings. If it matches the following criteria, it's probably a bird collision [1]:
1. Bird’s body remains intact, with signs of broken bones or blood spitting. Fewer visible injuries
2. Structures found within 5m of dead bird, e.g. exterior wall and noise barrier, are made of glass or reflective materials 
3. Surface of collision can reflect natural landscape, e.g. trees, mountains and distant sceneries 

What should we do when we encounter collision-related bird deaths? First, you may report the case to AFCD via 1823. If you find an injured or baby wild bird, please follow KFBG guidelines. Second, you can report suspected cases of bird collision with the necessary information (i.e. date of collision, Location, Photo of injured or dead bird, Status of bird, Species (optional), Side of building, Detailed field notes (optional) to Global Bird Collision Mapper, or send us an email at This email address is being protected from spambots. You need JavaScript enabled to view it.. Hopefully the data collected will help monitor the bird collision in Hong Kong, and serve to promote bird-friendly building designs and to protect countless birds from harm.

GBCM is an online geo-mapping tool designed for registered users to report the locations of bird collisions with buildings and is available on desktop and mobile devices. The database is international and can be seen by anyone who visits the webpage.

Viewing the data
Visit birdmapper-flap.hub.arcgis.com  to view the bird window collision data
Reporting a Collision via website
Visit birdmapper-flap.hub.arcgis.com and click on "Report a Collision" to start reporting
Reporting a Collision via mobile app
Visit Apple Store 或 Google Play  and install ArcGIS Survey123 mobile app， then open the app You can access the main page with/without registration Click on the QR Code button. You can scan the QR Code shown in the right column to add "report a collision" to your survey
Input Detailed Information
1. Attach bird and environment photo(s) (maximum number of photos: 3)
2. Select location by either: Zooming in on the map and selecting the desired location by using the + or – icons on the left side of the map Typing in an address in the search bar at the top left of the map Clicking the button for geolocation Typing in Latitude and Longitude
3.  Select the side of the building where the bird was found
4.  Select the date and time of encouter
5.  Type in Species Alpha Code (You can leave it blank)
6. Search for the species by its common name (If you are not sure about the species, leave this field "Unknown")
7. Click on the status of the bird as either: Alive (seen, rescued, or escaped) Dead Multiple (multiple birds of the same species alive OR dead) No birds found at all (e.g. only bird imprint was found) Unknown
8.  Include detailed field notes (optional): Other information about the building/structure Other information about the bird The organisation involved for bird rescue and the relevant case numbers Weather