Seagrass @ Labrador Park ! (:

HELLO! :D

We are a group of 3 Secondary 3 girls who decided to adopt the seagrasses at Labrador Park for monitoring, with Team Seagrass helping us(:
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what are seagrass?
why seagrass?
who's who?
ecology of rocky shore
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Saturday, April 21, 2007
another blog!

We have just found another blog about Labrador Park! http://habitatnews.nus.edu.sg/news/labrador/blog/
This blog is done by a group of local naturalists and they have really cool pictures! It focuses more on the natural habitat and less on seagrasses though. Nevertheless, it is very interesting, go take a look at it!

Labels: additional info, ecology of rocky shore

- have you hugged a seagrass today? (: -
10:36 PM

Wednesday, April 11, 2007
monitoring session on 7th April (:

Early in the morning at 7am, we gathered at the pavilion next to the beach. We were going to conduct our first monitoring session!! Ms Yang and Ms Lim,both of whom work at National Parks (NParks) and are also part of teamseagrass, came down to help us.

However, the gate to the beach was only opened at 730am, so we started late and had to make sure we were quick so we could get everything done. When we finally got started, we realised that the tide was coming in, instead of being low tide as it was supposed to be. Teamseagrass, who went to sentosa the next day to monitor the seagrasses there, also experienced the extraordinary higher tide than usual, and are most concerned. Hopefully the effects of global warming will not be felt so soon...

We were going to try out a new monitoring method, where we would walk on the edges of the Thalassia hemprichii patch (as it is the biggest) and track the GPS coordinates every few steps. The previous method of 100 by 25 was deemed ineffective after a chat with the leader of seagrasswatch, Len Mckenzie. It was not a good method for monitoring as the patches of seagrass found here is mostly quite small and by using that method, we would have a skewed idea of the distribution of seagrass here.

However, as much as we wanted to start our actual monitoring, the tide was too high and the water was too murky for us to see the edges of the thalassia patch which was further from the beach. The smaller patch of thalassia which was nearer to the beach(yep, we found 2 thalassia patches that day(: instead of just one!) thankfully, was still visible and we quickly tracked the location of the patch and measured the percent coverage before all was lost to the tide.

While we were measuring the percent coverage, Ms Yang and Ms Lim found a little hermit crab! We found out that when going for monitoring sessions, it is always good to bring a container, a pair of chopstick and a fork along so we can poke around with the chopstick, dig the soil with the fork and place organisms found (like the hermit crab) in the container to take a closer look! After we looked at the hermit crab upclose, we let the little creature back into its natural environment and carried on with our work(: We should never bully the little creatures which live here and bring them home with us!

After we finished our monitoring of that little patch, we decided that we should bring home some specimens of Thalassia hemprichii, Halophila ovalis and common macroalgae to put under the microscope and learn more about the differences between algae and seagrass! This was for learning purposes, therefore it is justified to take one specimen of each(:

All in all, it was a fairly good monitoring session despite the tide, as we learnt how to do a real monitoring session and will be able to do our next one properly in June.

Labels: monitoring methods

- have you hugged a seagrass today? (: -
9:15 PM

Thursday, April 5, 2007
Second Recce at Labrador Park

On the 17^th March 2007, our group met up with people from teamseagrass for our second recce at Labrador Park. This time, we were going to test and find out which method to check for seagrass population density in specific areas would be the most effective.

Usually for monitoring, a horizontal transect line is laid out for 50m, and a vertical one which starts at the start point of the horizontal transect line is laid out for another 50m. GPS readings are taken at the start and end points of the transect lines, so we can find the same spot again on another day. A quadrat (a square-shaped border made of pipes, which have holes drilled into them and string passing through, holes, and basically looks something like a square grid) is then laid out at every 5m on the vertical scale. Based on a data sheet for the seagrass percent cover standards, we can estimate the percentage (amount) of seagrass there is in each quadrat.

The methods that we were considering were the random band method, 100m by 25m, or 50m by 50m. The random band method involves laying out transect lines as well, but instead of laying down quadrats at every 5m, the quadrats are thrown randomly around areas where there are seagrass patches. We decided not to use it, for it might leave us with skewed data. Instead, we debated over whether the 100m by 25m, or the 50m by 50 would be more feasible, but our questions were resolved when we laid out the transect lines. The seagrass patch mostly ended around the 50m mark, so it would not be very feasible to lay out the transects until the 100m mark.

Using the surroundings to help us benchmark the area, e.g. a pillar for the 25m mark, we made it easier to identify the area if there was a need to. At every 5m, we also took down notes of what was in the surrounding area, for example, rocks, halophila ovalis, colonial anemone, etc. This would help us to identify what were the factors that affected the presence of seagrass in the area.

Along the way, we had a lot of fun studying the many marine creatures that we saw and learning what they were called. For example, we saw the colourful Velcro crab, which covered itself with different types of algae as a form of camouflage, making it more difficult to spot. We also spotted other things like a nudibranch (a sea slug- the spotty green thing in the picture),

a red egg crab, hairy crab, and more! We eagerly look forward to our next session at Labrador Park! (:

click here for the TeamSeagrass post on the recce with nice photos!

Labels: monitoring methods, recce, Team Seagrass

- have you hugged a seagrass today? (: -
3:01 PM

WHAT ARE SEAGRASSES?

~DEFINITION~
Seagrasses are tidal and sub-tidal marine flowering plants (angiosperms) that have complete internal vascular systems and a structure of buried roots, with erected leaves.

~MISCONCEPTIONS~
Many people have the misconception that seagrasses are a type of algae, but that is not true! There are various differences between seagrasses and algae. For instance, algae does not have a vascular system nor roots, and while algae is made of duplicates of the same cells, seagrasses have different types of cells for different parts of the seagrass.

~FACTS~
There are currently 60 described species of seagrasses, with 23 species in the Indo-Pacific area.
The various seagrasses have evolved from water, to land, and back to water. All seagrasses are known to be able to complete their entire life cycles underwater, with the exception of one genus, the Enhalus, which has to pollinate above the water surface.
Singapore has a diverse range of seagrasses, which include the Halophila Ovalis (spoon seagrass), which are most common and generally grow in sand, mud or silt,

Where does seagrass grow?
Seagrasses tend to grow in sandy and muddy areas that generally have no rocks, coastal marine and estuarine habitats, and in sheltered and shallow areas where they are protected from the current and wave action.

WHY SEAGRASS?

Seagrass communities play a very important role in coastal ecosystems. They support life in more ways than one. They:

- are food sources for many animals such as dugongs, sea turtles and fish.

- provide a feeding place for shorebirds such as egrets.

- have a high primary productivity rate and are vital in nutrient cycling, they also provide a shelter and is a nursery and feeding grounds for shrimps, prawns, fish and crabs, which are commercially important.

- stabilize sediments and stops beach erosion.

- improve water quality, making the seas clearer when the sediments are stabilized.

- also act as oxygen pumps when they photosynthesize.

- stop land-based pollution as they act as nutrient, sediment and chemical filter.

- have a buffering effect (that they filter nutrient and chemical inputs from land and trap the nutrients.), which stops land-based pollution .

- have important biological interactions with coral reef and mangrove habitat and without seagrass communities to trap sediments, the beautiful coral reefs that we admire may not be around!

- are also the 3rd most valuable ecosystem globally, after mangrove and rainforests

So you may ask, why should we monitor these habitats?

Well, monitoring seagrass habitats provides coastal management agencies with information and allows greater confidence in decision-making. You wouldn’t like the government to build the Integrated Resort right over a seagrass habitat, killing all the life within it, would you? Global, regional and local trends also show that this important coastal habitat is in decline, and by monitoring, we would be able to save the habitat.

In addition, seagrasses are considered a bio-indicator, which means that they can “tell” us when major coastal changes are about to happen. This is possible as they are sessile populations – not able to move if they sense danger – and are easily measurable. They cannot run away, but have to adapt to any changes. Thus, by monitoring them, we would be able to observe for any unusual trends and give an early warning for any major coastal changes.

WHO'S WHO?

Here's an introduction to the people who contributed to this project in one way or another! (:

Team Seagrass!
Team Seagrass is the local seagrass watch organisation! they comprise volunteers from all walks of life and are very enthusiatic about seagrasses!

Seagrass-Watch

Seagrass-Watch started the seagrass watch project and is based in Australia

NParks

link

ECOLOGY OF ROCKY SHORE

Rocky Shore Zonation

There are generally 4 zones on rocky shore: Splash Zone, Upper Shore, Middle Shore and Lower Shore.

Splash Zone
The splash zone is the highest part of the rocky shore, it only receives occasional splashes of seawater when the tide is unusually high. Thus, the organisms found here tend to be more terrestial, e.g. Lichens. Organisms found here can also survive without seawater.

Upper Shore
The upper shore is mostly covered only during extremely high tides (spring tides), thus it is usually exposed. There is little bio diversity here, and the organisms found here have special adaptations to prevent drying out and are able to cope with severe water loss.

Middle Shore
The middle shore is around mean sea level, and is submerged for roughly half a day for each day. It has more bio diversity than the upper shore and splash zone.

Lower Shore
The lower shore is covered for most of the day, exposed only during extremely low tides (spring tides). The organisms here are exposed to little sunlight, and are more marine than those found at the splash zone.

This is a very general overview of rocky shore zonation. The organisms found at each zone differ at different places and we apologise for not having much information on organisms found at the rocky shore at Labrador Park as we have not had time to explore much.

GALLERY

photos up soon!