Wednesday, June 09, 2004


Finally, our last fieldtrip ended on 26/03/04 with a final mapping session for the mudflat at KR3. The following two weeks were an extensive report writing period. Luckily, we were still able to complete the full report and submitted to the department on time (02/04/04).

Feedback, experiences and lessons

General problems/mistakes:

  • More time should spend on report write-up, should starts write-up earlier
  • Literature search: should cover more on sampling method and mangrove zonation in the beginning, avoid not enough time look up for information during fieldtrips period
  • Too many things to do during fieldtrip period (Jan to Mar): website, species identification, look up for literature etc
  • Schedule of fieldtrip: cancellation/wasted fieldtrips due to bad whether, clashes of class with good low tide day
  • Not enough helper when extra fieldtrips need to be carried out
  • In general, researcher is inexperience in planning and organizing the schedule for the research, better planning need to be done and execute properly

  • Act quickly, such as approaching seniors/graduate students actively (especially for prawn species identification), more discussion/catch-up with siva etc
  • Be self-independent and dynamic, settle thing fast and focus
  • Plan each fieldtrip well with clear target and objective, self debrief after every fieldtrip
  • Learning from mistakes made through out the period

    All in all, really appreciate the hard time in the process with lots of mistakes made, and realised that time allocation, planning and organization of schedule is extremely important.

    Many thanks to Siva for his introduction to the topic, helps and guidances throughout the project period, and to A/P Peter K. L. Ng for giving the opportunity and discussions made to the study. Thanks to Darren, Daisy and Yi Xiong for the guidances on prawns species identification. Thanks to Kelvin, Swee Hee, Tommy, Mr Yeo, and the rest of the seniors from Systematic and Ecology Lab, for the advice and encouragement given. Thanks also to the volunteers helping up during the fieldtrips.

  • Creating the gallery

    Photos took throughout the project period were uploaded at the gallery of the webpage. Siva thought that I am using ACDSee to create the gallery but actually I was using a very useful software available to download for trial which has help me create the gallery easily: Express Thumbnail Creator (ETC). ETC allows us to quickly and easily create web image galleries with thumbnails, even if we have no idea about HTML and graphics.
    Nevertheless, I did edit the html page myself to improve the navigation. There were other softwares used to create the website of the project, which included: Microsoft Front Page, ACDSee and ws_ftp.

    Two Unidentified Prawns

    Throughout the sampling fieldtrips, there were two prawns caught remain unidentified at the present time despite consultation with Yi Xiong. However, according to him, there was a high chance that one of the prawn is Salmoneus singaporensis, the new species recently described by Arthur Anker; while the other prawn might be anotehr species from Salmoneus genus. This is quite an interesting finding as prawn species from Salmoneus genus have not been reported at Sungei Buloh before.

    Friday, March 19, 2004

    The time in Dungeon

    Dungeon has been our working area throughout the research period. It serves as a:

  • Lab for me to identify the prawns, taking measurements and sort out the samples
    Microscope and forcep are the main equipment to identify the shrimps. The live shrimps were put into the freezer in dungeon, let to die in cold and eventually preserve in alcohol 75%.

    Identifying the species of prawn

  • Washing point for us to clean our equipment
    As every fieldtrip we went down to mangrove, the equipment was clean to get rid of mud by washing them thoroughly at the sink of dungeon, the equipment included: measuring tapes, sieves, all vials and boxes, and also, our booties.
  • Storeroom to put our equipment, specimens and reference books

    Throughout the period, most of the time spent in dungeon was to sort out the species of prawns collected after every fieldtrip. It takes time to get myself familiar with the skill and technique to identify the species of the prawns by observing their morphological characteristic under microscope. Working alone in dungeon sometimes did made me feel lonely, as nobody will talk to you except the sound of aircon and the radio provided by Yi Xiong. However, it is a good place to focus and concentrate as there are no distraction.

  • Do not take photo for the sake of taking

    On 13th March 2004, I took some photos of the snapping shrimps at the study site. However, a big mistake was made as I purposely place the snapping shrimps on the mud which has already disturbed by us, pretending that the shrimps were at their natural habitat. Siva was quite upset for this as the photos do not reflect the true behaviour and natural habitat of the snapping shrimps.

    Alpheus euphrosyne, artificially place on mud

    This reminds me of a friend from photocomm in Sheares Hall, who has taught me that as a photographer, never take photo without a subject or purpose; if not, the photos will be meaningless. Anyway, on a second note, it is very challenging to take photo of the snapping shrimps with their natural habitat, as these shrimps used to sheltered from sunlight and burrowed in the mud.

    Monday, March 01, 2004

    8th sampling fieldtrip- setting up quadrates

    27th Feb 2004, Friday
    Time:8:30-11:30 am
    Attendance: Fiona and Yenling

    Aim of the fieldtrip today:

  • set up quadrates at the possible site of snapping shrimps, including the surrounding.

    Today, quadrates were set up at 2 sites by listening to the popping sound from ground:
  • channel between Sungei Buloh East and KR4
  • right main stream at KR4, from mud bank across to the stream

    Observation/ Results:
  • Both juvenile and adults snapping shrimps were found at both sites. They were collected and brought back for gender and species identification.
  • Popping sound heard came from the specific area only. As quadrates were set up in line to the stream and the other side of mud bank at right main stream, no snapping shrimps were found.

    The prawns bought back were kept alive to put back to the study site on the next fieldtrip. However, some of them die after a few days. It was observed that the snapping shrimps fight with each other (territorial?) and eventually die.

  • Tuesday, February 24, 2004

    Fieldtrips on last week - 6th and 7th Sampling

    2 fieldtrips were conducted last week, on 18th Feb 2004 and 21st Feb 2004, respectively.

    18th Feb 2004, Wednesday
    Attendance: Fiona and Yenling
    Time: 2:30pm-5:30pm

    Once we reached KR4, Fiona went to find her horseshoe crabs while I continued to look for snapping shrimps. Today I aimed to test the method of detecting snapping shrimps by listening to the popping sound. A pole was used to hit on ground frequently wherever I went, this is to increase the disturbance on ground and thus serve as a fast scanning method on snapping shrimps distribution. I went through the mud bank on the side of Stream 2 (right main stream) and eventually return to the previous point where we found numerous of snapping shrimps to compare the difference.

    Observation/ Results:

  • The mud bank of stream 2 is covered by a lot of dense tree roots generally, popping sound was heard from the roots especially in between of pneumatophores. I tried to look for the shrimps from that area but unsuccessful due to the densely grew roots. Only one snapping shrimps was discovered at the end of fieldtrip.
  • Three Potalmalpheops spp. was found as I turn over a wood plank which covered half of the surface of a water pool. They were distinctly different with the other shrimps as their bodies were striped with bright purple color.
  • The method of using pole scanning through the area was not effective and sensitive enough. The popping sound did not increase significantly when the pole was hit frequently on the ground.
  • Less snapping shrimps was observed at the previous area where large colony of snapping shrimps was discovered. Only 2 snapping shrimps were found in 30 minutes even though popping sound was heard.

    Discussion with Siva
  • Snapping shrimps in between of the roots were very hard to find, the shrimps might be able to throw the sound which confused us its exact location. It is necessary to mark on map the location where sound was heard.
  • Less snapping shrimps found today might be due to:
    - time of fieldtrips different, more shrimps were close up to the mud surface in the morning instead of evening (last fieldtrip was carried out in morning).
    - too many shrimps were collected from the previous point last time, therefore the population there have not been recovered yet.
    - found at the wrong location, the distribution of the shrimps might be very patchy and specific.

    21st Feb 2004, Saturday
    Attendance: Fiona, Yenling and Ming Sheng
    Time: 3:30pm-6:00pm

  • The tide was quite high at 3:30pm once we reach there. We started off from KNTB1 (Kranji Nature Trail Bridge 1) to remap the area (Buloh east channel) to include the tree lines and its distances. After that I continued my sampling at Buloh east channel.
  • I decided to return to the 1st point where we found snapping shrimps again, popping sounds was heard and we started to look for them in the mud. With the helps of Ming Sheng, we are able to found 10 Alpheus spp. in about 40 minutes. After that I walked inside towards KNTB1 from that point, however, almost no popping sound was heard along the mud bank. Similar habitats (with no popping sound) were searched and no snapping shrimps were discovered.
  • Before fieldtrip end, I walked along the mud bank of right main stream at the other side, popping sound heard came from the roots.

    After these 3 fieldtrips of finding snapping shrimps, large number of Alpheus spp. was found at one specific area. The shrimps might be in between of the dense roots but low chances of finding them.
    Quadrates will be set up during the following fieldtrips at possible area of finding the snapping shrimps.

  • Saturday, February 14, 2004

    5th Sampling Fieldtrip - looking for the Snapping Shrimps

    In the early morning yesterday, Siva, Fiona and me went for another sampling fieldtrip.

    13feb2004, Friday
    Attendance: Siva, Fiona and Yenling
    Time:8:30am - 11:30am

    Task completed:

  • Collecting sample
    Siva was supposed to show me the way to look for the mangrove snapping prawns (Alpheus euphrosyne and Alpheus microrhynchus ). At first we tried to listen the poping sound generated by the prawns but didn't really able to spot the location. Subsequently Siva found an area by his 'natural instinct' and we able to find the snapping shrimps! 29 adult snapping shrimps and some small prawns were collected at the end of fieldtrip.
    The prawns were kept alive to bring back, water sample and mud were collected from the same site to keep the shrimps alive for observation.
    * Visit Siva's blog: crawling for shrimps for more information.
    * photos taken at Sungai Buloh East Channel and the prawns collected.

    The small prawns collected from the same area were suspected to be the juvenile snapping shrimps, they were found when we looked carefully in the shallow water pools where channel were created purposely to drain out the water from that specific area.
    Beside snapping shrimps, some adult penaeid prawns were discovered hiding in the shallow water channel of that area. The penaeid prawns can be easily distinguish from the Alpheus spp. as penaeids prawns have big eyes and 3 pairs of chelated legs (pereiopods).

    Other stuff:
  • To measured the salinity of the water, refratometer has borrowed from EcoLab but none of us know the exact method to use it. Water sample has collected and the water salinity was measured after Swee Hee from Ecolab taught me the way to use the refratometer on the same day after fieldtrip. Thanks Joelle provided the miliq water!

  • Saturday, February 07, 2004

    An informal report on 3rd and 4th Sampling Fieldtrip

    This Wednesday (4feb2004) and Thursday (5feb2004), we went for 2 more sampling fieldtrips .

    4feb2004, Wednesday
    Attendance: Fiona, Grace and Yenling
    Time:3pm - 6pm

    Task completed:

  • Took photos from KNTB2 (Kranji Nature Trial Bridge 2)
  • Collecting sample
    Today I aimed to find Caridina propinqua from the study site, with the helps of Grace, we collected 3 samples of small prawns, 2 from the channel between KNT and Sungai Buloh, 1 from the main river near KNTB2. After identification at lab, only one of the samples is Caridina propinqua, it was found at the upstream part of the stream, shallow slow flowing water under KNTB1.
    Other observation: along the middle stream at the channel between KR4 and Sungai Buloh, we found quite a lot of juvenile Macrobrachium equidens, they can be easily recognized by the orange white colors legs (pereiopods). Subsequently, we found a group of adults Macrobrachiums equidens (up to 8cm) in a water pool in between the stream.

    Other stuff:
  • Saw a huge large fish at the left main stream, photos taken. After asking friends good in fish, it was suspected the fish is the snake head fish, toman, a freshwater fish. It might be came from the Kranji reservoir nearby.

  • Apply more insect repellent if you are going to the area near mud lobster zone, which occurred as I walk upstream towards KNTB1 and collected one of the sample there. The result was we (Grace and me) end up seeing doctor at YIH the next day to get some insect bite cream!
    * for other lessons please refer to Fiona blog: 4th Feb Fieldtrip

    5feb2004, Thursday
    Attendance: Fiona, Wendy and Yenling
    Time: 3pm - 4:30pm

    Task completed:
  • Went back to the location where Caridina propinqua was found yesterday and look for it along the stream from the point, some samples collected.
  • Continued look for Caridina propinqua from the other side (right main stream), found some small shrimps in the deep water pools at low tide, they might be other juvenile marine shrimps but further identification needed.
  • End fieldtrip earlier due to the rain.
    Other observation: as I went back to the point where large adult Macrobrachium equidens were found, the large shrimps were all gone! They might be gone back to sea during high tide at the morning?

    Other stuff:
  • Better read the weather forecast before the fieldtrip to avoid unexpected heavy rain
  • Towards the end of fieldtrip, met a middle-age uncle walking in the mud, he is looking for crabs to bring back home! As I was collecting sample alone there, I decided went to another side together with Fiona and Wendy.

  • Tuesday, February 03, 2004

    The second sampling fieldtrip

    The second sampling fieldtrip was scheduled On 2feb2004. Despite the drizzling rain, we went to Sungai Buloh from 2pm to 5pm. As we were able to get Prof. Peter Ng and another experienced shrimps taxonomist, Mr. Cai Yixiong to come along, we aimed to find the all six species of mangrove shrimps previously found from Sungai Buloh.

    At the beginning, we focused on finding the less common small prawns species, these included: Potamalpheops tigger, Potamalpheops johnsoni and Athanas Polymorphus. As recent studies reported that the Potamalpheops spp. and Athanas polymorphus were found at shallow water pools under roting log, we tried to look for these type of microhabitat, turned over the log and look for the prawns. However, as the luck was not with us, after trying for almost 3 hours, we only managed to get a juvenile Alpheus spp. and 2 small prawns, either Potamalpheops spp. or Athanas spp. The prawns were kept alive in plastic container filled with seawater.

    On a second note, there were quite a lot of juvenile marine prawns observed from the study site. These marine prawns included Penaeide prawns, Macrobrachium spp. and Palemon spp. As mangroves have been always the nursery area for marine prawns, these juvenile marine prawns found in mangrove were just 'visitors' rather than 'residents' of mangroves. However, these juvenile prawns were similar to the true small mangrove prawns in terms of size (both about 1-1.5 cm in length), they can be differentiated at field by observing the color, body shape, rostrum and the eyes morphology.

    Equipment used for this sampling included: small hand net, clear plastic containers or ziplock bags (filled with clear seawater, enable to differentiate to genus level of the shrimps) and some Nalgene bottles with 75% alcohol (to kill and preserve the prawns).