first person

PUBLISHED : Thursday, 30 December, 2004, 12:00am
UPDATED : Thursday, 30 December, 2004, 12:00am

City University marine biologist Katherine Lam King-yiu, 33, is using a swimming robot to study corals at Hoi Ha Wan Marine Park. She now hopes to see at least one more robot put to work along other parts of the Hong Kong coastline.

It's a small, swimming robot. Its technical name is a remote operating vehicle, or ROV, and we use it to observe coral and coral fish in Hoi Ha Wan Marine Park. We believe this is the first time something like this has been used anywhere for observation in shallow coral areas.

We developed it in collaboration with our electronic engineering department and it cost about $200,000 to build. It measures 40cm by 30cm and effectively it's a small swimming vehicle which examines the seabed.

It connects via an umbilical cord to the land so we can drive the robot while it swims and records a video. We get to see real-time images on the shore on a display unit in the laboratory.

The robot enables us to record the coral density, the health of the coral and how it looks and whether it is damaged.

We also have other equipment in use such as underwater surveillance cameras.

Using this sophisticated equipment, we can maintain 24-hour surveillance of the coral areas and see what the fish and invertebrates are doing.

The robot has been in service for about eight months. It is doing the work that would usually be done by a diver. There are two advantages in using a robot: first it can be dangerous work for a diver; second, the robot can stay in the water for longer. With a ROV, you can explore dangerous places that a diver could not.

The robot's mainframe was developed in Switzerland. These devices are used in other places around the world to observe seabed conditions. It is usually used to explore deep sea areas that divers can't reach or stay for long. This is the first time it has been used to observe shallow coral areas.

Traditionally, marine biologists prefer to use divers for taking videos, but in Hong Kong the situation is different from other coral areas because the water is very murky. As a result, there is a potential danger in using divers, so using the ROV is a good alternative.

We would like to expand this project to other coral areas in Hong Kong. We hope to be able to get at least one more ROV so that we can look at coral areas in different parts of Hong Kong to give us a better comparison. Then we will know more about the health of the coral in different places.

We have been using the laboratory at the Marine Life Centre since last year but I have been working in Hoi Ha Wan for a long time. My PhD thesis was based on Hoi Ha so I have spent nine to 10 years looking at the area's ecology.

Hoi Ha Wan is a special site because it is well protected and has a diverse habitat. There is a stream at the back of the bay where you can look at the fresh water ecology and there are mangroves and small sand flats. In one small area you have a lot of different habitats so it is a very special place for ecologists.

There are few places in the world you can get several habitats in the same place but Hoi Ha is one of those places. It is an ideal place for educational purposes because you can bring students and introduce them to different habitats and animals in one day.

The coral in Hoi Ha has been maintained quite well this year compared with last year. I think the Agriculture, Fisheries and Conservation has done quite a good management job, and probably people are becoming more aware of conservation. People are starting to know what corals are and how to avoid harming them.

With the equipment we have at Hoi Ha Wan, we can get detailed information about what the sea is like. All the environmental factors can be logged and we can see how things change in the water from season to season. We can even see how it changes from one hour to the next.