Dykking & Marinbevaring - Frivillig Arbeid i Kambodsja: Månedlige Oppdateringer
Conservation in Cambodia - Monthly Update March - April 2015
During the past two months, we have continued with our reef surveys and added more variables to our studies of coral reefs, such as turbidity and sedimentation rate. A programme to assess the coral health (CoralWatch) was added, which is conducted mainly by short-term volunteers. We continued with our seahorse surveys, although by the end of March we had reduced the time spent in these surveys due to very few specimens being found. Although our seahorse survey will continue, we are now focusing more on other areas, such as mangroves.
Our marine pollution programme was running as normal, although we covered a bigger area during this period and therefore collected higher amounts of debris. Several beach clean-ups have also been done on different islands of the archipelago.
We have started our English classes in the local primary school, where we go every Tuesday and Thursday in the morning and in the afternoon. So far, it has been very interesting for the volunteers to have this regular contact with the local kids and it has been very rewarding to teach them.
We hope to finish the preparations for a special event with the community at the end of this month, for which all kinds of materials and activities are being developed by our enthusiastic and helpful volunteers.
Coral Reef Programme
The reef surveys along the archipelago have continued and the variable turbidity has been added to the study using the Secchi disk. The Secchi disk is commonly used in oceanographic studies to measure the water turbidity, which is related to the extinction coefficient for the available light averaged over the Secchi disk depth. Using recycled materials, we have constructed our own Secchi disk, which we have started to use in the morning reef survey as the period for best results is between 10am and 2pm.
A new programme to assess the coral health has been implemented recently, following the guidelines of CoralWatch. An underwater chart with colours and codes standardises changes in coral colour, providing a simple way to quantify bleaching and monitor coral health. This programme is easy to conduct and is perfectly suitable for those volunteers staying only for a short time, as it doesn’t require a lot of training. Furthermore, it gives valuable information about the health of our corals, which can be combined with our current reef surveys.
Another variable that has been added the in recent months to our reef surveys is the sedimentation rate. For that purpose, several homemade sediment traps (Fig.1) have been placed at our study sites, to collect sediment over time at 5m and 8m. The quantification is made when the collected sediment is dried and weighed, and related to the time. We have observed big extensions of corals profusely covered by sediment, which ultimately suffocates the polyps underneath. For this reason, we want to find out the rate at which this sediment covers the corals and in which degree this rate allows the corals to overgrow the sediment over them.
We have completed a total number of 23 surveys during March and April. At Koh Toteong, 19 sites were completely surveyed, and only four more surveys are needed to complete all sites there. On Koh Andech (Turtle Island), two surveys have been completed so far, and five surveys on Koh Chan.
Running current reef data through statistical package R, many relationships and correlations have been found between the different variables. The more significant correlations are shown in table 1:
Once all Koh Toteong survey sites have been completed, we can do more in depth analysis between Koh Kmauk and Koh Toteong.
CoralWatch training and surveys started mid-April with all current volunteers trained to do the surveys. All volunteers completed a CoralWatch workshop (presentation and some activities about coral bleaching and assessing level of bleaching). They then completed one practice CoralWatch Survey where they looked at 25 separate hard corals on a transect. There have been two completed CoralWatch Surveys, with data for one put directly on to the official online database. Data will now be entered straight on to a prepared excel sheet, which automatically shows a summary of the data. The summary shows average bleaching levels, different types of corals in the areas and many other interesting variables.
We are currently waiting to order new materials from CoralWatch which will include extra training and educational materials as well as new smaller colour chart slates.
The survey structure:
- 50m transect, assessing any applicable corals (no blue/purple corals, no repeats of same coral) at every 1m point
- CoralWatch has a minimum of 20 corals assessed during each survey, so the 50m transect allows us to maximise the number of data we collect
- All surveys are currently held at 5m or shallower (below this depth it is necessary to use a torch)
- The surveys are conducted in buddy pairs – buddy 1 has the slate to record data, buddy 2 has the CoralWatch colour chart
During the months of March to April 2015, we have carried out 11 underwater surveys and six landings surveys. Towards the end of March, we decided to reduce the amount of time spent surveying seahorses; this is why there are fewer results for April.
During the last two months, we have carried out 11 underwater surveys, and seen two seahorses. Both seahorses have been identified as Hippocampus spinosissimus. One was found on the East coast of Koh Chan, using leaf as a holdfast. The other was found close to Ghost Island on a piece of dead algae. Over the two months, we spent about 10 hours surveying underwater, and we surveyed five different islands.
We carried out six interviews over the last two months, and we were shown two dried seahorses (both H. spinosissimus). The majority of the seahorses were caught as bycatch by trawling boats. One problem with doing landings is that almost everyone has caught a seahorse, most of the time over one year ago. This means that the data we collect could be inaccurate and no longer relevant. This also shows us that seahorses are not caught very often, and are therefore quite rare.
The dried seahorses are mostly sold on Koh Sdach or in Sihanoukville. Some are added to a bottle of Koh Sdach’s finest rice wine. Once the wine is finished, the seahorses are fried and eaten.
Comparing the March - April 2015 with December 2014 - February 2015, we have not seen an increase in the number of seahorses spotted underwater. In fact, we have carried out the same number of surveys but have seen one less seahorse.
The majority of volunteers don’t see a seahorse while at the project. Since the project began, we have seen five seahorses. Out of the 60-70 volunteers that have been on the project, only 17 have seen a seahorse underwater.
The seahorse landings questions will be changed, so that we only interview fishermen who have seen a seahorse within the last year.
Mangrove Restoration Programme
In April, we visited a community-based mangrove restoration project in Kampot province. With the support and funds from several NGOs, the fishermen of this community are managing the areas of mangrove where they usually fish, actively protecting them from the illegal fishing. Our work consisted in the collection of seeds, or more properly named propagules, since the seeds germinate while still attached to the mother tree. After that, we planted the propagules into small bags of muddy sediment. On the second day, we planted around 20 already-grown mangrove baby trees into the definitive area where they will cover areas that were previously deforested. It was a very interesting trip and all the volunteers were very enthusiastic with the working days at the mangroves.
Now we are seizing the possibility of implementing a similar restoration programme at the mangrove forest located close to our island (five minutes by boat).
Marine Pollution Program
During March and April the total amount of garbage extracted from the seabed accounts to 163.85 kilograms, of which 73% are discarded fishing nets, fishing lure and other debris associated to commercial fishing, 22% are different metal objects, and surprisingly, just 2% are other plastic items not associated with fishing (Fig.2).
In the last two months, Projects Abroad volunteers have spent a total of 15 hours collecting marine debris and have swept an area of 1550 m2 around the Koh Sdach Archipelago (Fig.3) compared to the 1345m2 in February-March (Fig.4).
There is a big increment in the total amount of garbage in comparison to the last two month period, from 84.8 kilograms in January-February (Fig.5) to the 163.85 kilograms in March and April (Fig.6). Presumably the reason for this is a better choice of the areas that are subject to underwater cleaning.
During the past two months, we have focused our efforts on those areas where higher concentration of marine debris was found during January and February. There is a difference between the amounts of debris found at Koh Kmauk (Ghost Island) between both periods, although around the other islands the amounts are similar.
For the next months, we will continue collecting debris by organising our dives in two different ways:
- Random dives around the different islands: taking data (mainly kilograms and area) and analyse if our job is having a real impact and measure it.
- Specific dives: diving repetitively in the same spots, so as to measure at what rate the marine debris (and specifically those associated with fishing) is back in our ocean.
Community & Education programme
We have started our English classes in the local primary school, two days a week for four different groups of grades 4, 5 and 6. Our volunteers actively participate in the development of educational activities and games, and teach the kids by following the pre-established programme that has been provided by the School Director.
Our programme with the Green Protectors is temporarily in a pause until the corresponding permits from the local authorities are granted.
For a special event with the community that will be held soon, our volunteers were preparing all the necessary materials. The event will consist of a massive town clean-up with Projects Abroad volunteers and staff, and members of the local community. There will be educational activities, a communal lunch for everybody, and several presentations in the local school about the marine environment, addressing the problems of marine pollution, and offering feasible solutions to be applied by everyone in the community. The presentations will be offered by the Green Protectors in Khmer, and our volunteers are currently preparing the contents and main features of the PowerPoint presentations.
Upon request of the volunteers, who by now are all different from the previous months, we have organised another Khmer cooking class. The cooks, Mab and Kvat, are now used to teaching our “barang” (white people) volunteers. They lead them through the market to buy the ingredients and teach them how to present different typical Khmer dishes. All the volunteers have worked during the process of peeling, cutting and chopping the ingredients and mixing the spices to make tasty and delicious food, which becomes our lunch meal afterwards. A detailed recipe is being created with pictures to put together with other recipes for a Khmer cooking booklet that we are planning to develop.