I asked the wonderful peeps over at the Hong Kong Bird Watching Society (HKBWS) to introduce themselves, activities and also what is going on at the moment, and they kindly replied with the following...and yes, I am a member, and yes, you should be too!
website for more information: https://cms.hkbws.org.hk/cms/en/
Founded in 1957, the Hong Kong Bird Watching Society (HKBWS) is one of the earliest non-governmental organizations in Hong Kong. It aims to promote the appreciation and protection of birds and their habitats through education, research, habitat management, and conservation advocacy. It was recognized as an approved charitable institution of a public character in 2002. Since 2013, HKBWS is a partner of BirdLife International – a global alliance of conservation organizations working in more than 100 countries and the world’s leading authority on bird conservation.
Currently, Hong Kong has a list of over 550 recorded bird species. A high proportion of them are winter visitors and passage migrants, followed by resident birds; there are comparatively few summer visitors. The best time for watching birds in Hong Kong is between September and May. HKBWS regularly organizes bird watching outings for members of the Society and the general public year round (except for July and August, click here to see the latest information).
Note: unfortunately, these are suspended due to COVID-19
Now is the spring passage (generally from March to May), when it is a good time to visit the Deep Bay area for unusual and rare shorebirds. Besides, there are many other migrants to look for, including terns, raptors, needletails, warblers and buntings. Migrating flycatchers and rare warblers are found in the woodlands. By mid-April, the breeding season is in full swing for resident species and newly arrived summer visitors, such as drongos and orioles. Throughout the day, and even at night, a variety of cuckoos call monotonously. To see and hear a good range of Hong Kong’s woodland species, visit Tai Po Kau in the early mornings in early May. Let’s get up and try your luck to see what birds are out there waiting for you!