Treasure of Marine Biodiversity in Tolo Harbour and Channel

 繁   简   Text Size 

This website serves as an educational tool to visualize species records from ecological surveys conducted in the Tolo Harbour and Channel (the Tolo area) over three years as part of the Ting Kok+ project funded by the  Environment and Conservation Fund , as well as data from other ecological studies and surveys conducted in the Tolo area going back as far as the 1970s. This website synthesizes the species records from ecological surveys conducted in the Tolo area into a single marine biodiversity database, with species identification guides provided for some common species, so that the public can learn more about the species found in the Tolo area during their exploration. The website comprises different sections to introduce the background of the Tolo area including: 

1. Regional Topography  
2. Historical Development
3. Biodiversity  
4. Species Richness
5. Temporal Tidal Variation
6. Habitat Diversity  
7. Species Gallery   
8. Field Guide to explore the Tolo area
9. Marine Biodiversity Map

The approximately 50 sq. km area of Tolo Harbour and Tolo Channel (the Tolo area) is situated in the northeast of Hong Kong. The area consists of a shallow, semi-estuarine inner harbour, which deepens to a narrow tidal channel (the Tolo Channel) opening into Mirs Bay in the South China Sea, with water depth increasing from ~5m in the inner harbour to ~20m in the Tolo Channel.

Tolo Harbour and Channel have been the important fishing grounds for local people since the Sung Dynasty, including being the site of aquaculture for pearls. The Tolo area was formerly dominated by extensive mangrove stands along the shoreline, but 42% of the mangroves and 22% of the natural shoreline have been lost as a result of reclamation for the development of Shatin and Tai Po new towns during the 1970s.

Subsequently, due to the development of these new towns, Tolo Harbour was heavily polluted with untreated sewage and livestock waste in the 1970-80s but, after a number of mitigation measures taken by the government throughout the 1980s, water quality in the Tolo area has been improving over the past decades.

Tolo Harbour and Channel are surrounded by different landscapes ranging from natural, remote and hilly terrain to developed, highly-populated towns. As a result of this habitat diversity, the area accommodates a variety of species, which have attracted scientists to study the rich biodiversity in the area. The results of such studies have been gathered together and integrated into a biodiversity database which you can explore here.

Today, the Tolo area supports a rich diversity of coastal habitats including mangroves; sandy and muddy shores; hard-rocky and boulder shores as well as subtidal and open water habitats, all of which harbour a vast variety of species. Due to this rich variety of marine habitats, more than 1,000 species have been recorded in the Tolo area during the past few decades which constitutes ~25% of the total number of species recorded in Hong Kong waters.

The vertical distribution of intertidal species is determined by the cyclic rise and fall of the sea: one such rise and fall is called a ‘tidal cycle’, caused largely by the interaction of forces generated by the Sun and Moon. In general, tides occur twice a day in Hong Kong during new and full moon periods when the amplitude of the tides is large (the so-called spring tides); but it can be reduced to once a day on half- and three-quarter moon phases when the amplitude of the tide is also reduced (known as neap tides). 

This timelapse video represents a 3-hour tidal cycle in one of the intertidal areas in Tolo Harbour. As the tide rises towards high tide, the soft shore is wholly submerged; while, when the water retreats and the tide falls, more of the shore is uncovered and many species, such as snails and crabs, will become active and feed on the shore. These intertidal patterns can, however, be very different across seasons in Hong Kong. 

Tides generally have a greater range in the hot and wet season (June-September) than the cool and dry season (December-March), and the lowest tides (known as spring tides) occur in the afternoon in the hot and wet season as opposed to very early in the morning in the cool and dry season. So, if you want to explore the seashore, low water tides during full and new moons in the hot and wet season are the best time to visit (see  Hong Kong Observatory website  for tidal predictions).

For your safety, you are encouraged to explore the Tolo area during summer afternoons, since daytime exposure makes the coastal regions more accessible.

In general, there are five major habitats in the Tolo area. Each habitat is characterized by different abiotic and biotic factors such as substrate type, wave exposure as well as species composition.

In this section you can find pictures showing other relatively common species that can also be found in the Tolo area. 

If you are going to visit the sites in the Tolo area, please follow these guidelines to ensure you are well prepared and can have a safe and rewarding visit.

You can follow the instructions to help you use this simple species identification key to help identify the common organisms you may observe and encounter on the shore.

This map contains species records from different ecological surveys conducted in the Tolo area. Please use the filter function to narrow down the species records to those you are interested in. By clicking such species records, you can see the photo identification guides for common species to help you identify the organism you observed. 

(Please click  HERE  for the User Guide of the Simplified Version of Marine Biodiversity Map)

This map contains more functions to help users to extract species records according to different queries such as habitat and location. The query results can also be overlapped so that the users such as researchers or scientists who are interested in species distribution patterns within the Tolo area can utilize the biodiversity data more flexibly.

(Please click  HERE  for the User Guide of the Professional Version of Marine Biodiversity Map)

Here we present video demonstrations on functions that were presented in this website and the mobile app version.

1.  AFCD  Website
2.  AFCD Ting Kok+ website 
3.  AFCD Visitor Code for Visiting Coastal Area 
4.  ECF Ting Kok project website 
5.  Tidal Prediction from the Hong Kong Observatory 

Special thanks for sharing their expertise and providing materials, images and videos for this web-based education tool are given to:

• Colleagues and co-workers at the Division of Ecology & Biodiversity, The University of Hong Kong;
• All the many team members from the  Ting Kok+ Project  funded by the Environment and Conservation Fund:
• The University of Hong Kong (HKU),
• City University of Hong Kong (CityU),
• Hong Kong Baptist University (HKBU),
• Hong Kong University of Science and Technology (HKUST),
• The Chinese University of Hong Kong (CUHK) and
• The Education University of Hong Kong (EdUHK);
• Prof. Gray A. WILLIAMS and team members from the TIDE Group, The Swire Institute of Marine Science, HKU;
• Dr. Stefano CANNICCI and his team members from the iMEco lab, The Swire Institute of Marine Science, HKU for information on mangrove systems in Tolo Harbour, also supported by the Environment and Conservation Fund;
• Lands Department

The following team were involved in the design and development of this education tool:

WILLIAMS, G.A. (HKU), CANNICCI, S. (HKU), QIU, J.W. (HKBU), CHENG, M.C.F. (HKU) and GU, V.Y.F. (HKU) 

This website synthesizes the species records from ecological surveys conducted in Tolo area over three years as well as other ecological studies in last few decades in order to demonstrate rich marine biodiversity in Tolo area. This website, serving an educational tool, visualizes the marine biodiversity database with species identification guide provided for some common species so that the public can learn more about the species in Tolo area during site visit using the tool.

This website adopts web accessibility design and conforms to the World Wide Web Consortium (W3C) Web Content Accessibility Guidelines (WCAG) 2.1 Level AA standard. Should you have any enquiries or comments on its accessibility, please contact us by e-mail.

E-mail address :  mailbox@afcd.gov.hk 

The information within this website may be re-disseminated or reproduced, provided that Agriculture, Fisheries and Conservation Department (AFCD), as the source of information, is acknowledged and that the re-dissemination or reproduction is for non-commercial use. Any other reproduction, adaptation, distribution, dissemination or making available of the information within this website for commercial use is strictly prohibited unless prior written authorization is obtained from the AFCD. The AFCD and the HKSAR Government shall not accept any responsibilities for any loss or damage arising from the information, or reproduction or re-dissemination of the information, within this website.

The information provided by the Government of the Hong Kong Special Administrative Region ("the Government") on this website ("the Government's information") is for reference only. Whilst the Government endeavours to ensure the accuracy of the Government's information on this site, no express or implied warranty is given by the Government as to the accuracy of the Government's information.

This website also contains information input by other parties and users may link this site to other sites and obtain information provided by other parties (collectively called "the other information"). The Government expressly states that it has not approved nor endorsed the other information contained in or in connection with this site. The external links are for users' convenience and the information provided is the responsibility of that external source.

The Government does not accept any responsibilities for any loss or damage whatsoever arising from any cause whatsoever in connection with this website. The Government is entitled to delete, suspend or edit all information on this site at any time at its absolute discretion without giving any reason. Users are responsible for making their own assessments of all information contained in or in connection with this site and are advised to verify such information by making reference to its original publication and obtain independent advice before acting on it.

The Government of the Hong Kong Special Administrative Region ("the Government") is concerned to ensure that all personal data submitted through www.afcd.gov.hk are handled in accordance with the relevant provisions of the Personal Data (Privacy) Ordinance (    https://www.elegislation.gov.hk/hk/cap486!en?INDEX_CS=N  ).

For different purposes and at different times you may be invited to provide personal data to the Government through www.afcd.gov.hk on a voluntary basis. Personal information may include name, telephone number, mailing address or e-mail address. The Government will specify the collection purpose and intended usage of your data when it invites you to provide such information and advise you how you may request access to or correction of the personal data provided.

Unless permitted or required by law, the Government will not disclose your personal data to any third parties without your prior consent.

This Privacy Policy has been translated into Chinese. If there is any inconsistency or ambiguity between the English version and the Chinese version, the English version shall prevail.

Marine Conservation Division (Biodiversity)

Agriculture, Fisheries and Conservation Department

Unit 2201, 22/F, CDW Building, 388 Castle Peak Road, Tsuen Wan, N.T.

E-mail: mar_con_biodiv@afcd.gov.hk

Office Tel.: 3468 5394

Fax: 3468 3014