life and death at chek jawa 9th august 08
TRANSCRIPT
LIFE AND DEATH LIFE AND DEATH AT CHEK JAWAAT CHEK JAWA
99thth August 2008 August 2008
I volunteer with…I volunteer with…
► Team SeagrassTeam Seagrass► Naked Hermit CrabsNaked Hermit Crabs► Semakau intertidal walks with Semakau intertidal walks with
Raffles Museum of Biological Raffles Museum of Biological Research (RMBR)Research (RMBR)
Key pointsKey points of this session of this session1.1. High Biodiversity of Chek JawaHigh Biodiversity of Chek Jawa2.2. Mass death on January 2007Mass death on January 20073.3. How this study began?How this study began?4.4. What caused the mass death?What caused the mass death?5.5. How are the marine animals recovering?How are the marine animals recovering?6.6. What is the future of Chek Jawa?What is the future of Chek Jawa?7.7. Experiences of this projectExperiences of this project
Have you been to Have you been to Chek JawaChek Jawa before? before?
Where isWhere is Chek JawaChek Jawa
Chek Jawa
Chek Jawa is lauded for its high Chek Jawa is lauded for its high biodiversity biodiversity
Figure from
Ria Tan
Six distinct ecosystems
exist at Chek Jawa
and it is abundant
with locally rare fauna and flora
Coastal Hill ForestCoastal Hill Forest
MangrovesMangroves
Rocky ShoreRocky Shore
Photos: N. Sivasothi
Sandy EcosystemsSandy Ecosystems
Photos: Ria Tan
Seagrass LagoonSeagrass Lagoon
Coral Rubble AreaCoral Rubble Area
Photos: Ria Tan
URA development guide plan 1997URA development guide plan 1997
To be reclaimed
Chek Jawa reclamation deferred!Chek Jawa reclamation deferred!
Key pointsKey points of this session of this session1.1. High Biodiversity of Chek JawaHigh Biodiversity of Chek Jawa2.2. Mass death on January 2007Mass death on January 20073.3. How this study began?How this study began?4.4. What caused the mass death?What caused the mass death?5.5. How are the marine animals recovering?How are the marine animals recovering?6.6. What is the future of Chek Jawa?What is the future of Chek Jawa?7.7. Experiences of this projectExperiences of this project
Mass mortality Mass mortality occurredoccurred
on January 2007on January 2007
After a period of exceptional heavy rain After a period of exceptional heavy rain in Jan 2007, a field trip to Chek Jawa in Jan 2007, a field trip to Chek Jawa
revealed…revealed…
LivingLiving Carpet Anemones Carpet Anemones
DyingDying Carpet Anemones Carpet Anemones
LivingLiving Sponges Sponges
DyingDying Sponges Sponges
LivingLiving sea stars and sea cucumbers sea stars and sea cucumbers
DyingDying sea stars and sea cucumbers sea stars and sea cucumbers
Soft bodied marine animals affectedSoft bodied marine animals affected
Key pointsKey points of this session of this session1.1. High Biodiversity of Chek JawaHigh Biodiversity of Chek Jawa2.2. Mass death on January 2007Mass death on January 20073.3. How this study began?How this study began?4.4. What caused the mass death?What caused the mass death?5.5. How are the marine animals recovering?How are the marine animals recovering?6.6. What is the future of Chek Jawa?What is the future of Chek Jawa?7.7. Experiences of this projectExperiences of this project
Asking Asking questionsquestions►What happened at Chek Jawa?What happened at Chek Jawa?►What caused the mass death?What caused the mass death?►Why were some animals more Why were some animals more
affected as compared to others?affected as compared to others?►Is this mass death a tragic event?Is this mass death a tragic event?►Will Chek Jawa recover? Will Chek Jawa recover? ►If yes, how?If yes, how?
Answering Answering questionsquestions through.. through..
UROPSUROPS
What isWhat is
U R O P sU R O P s
Undergraduate Research Undergraduate Research Opportunities Programme in ScienceOpportunities Programme in Science
►doing an independent research project doing an independent research project ►work with Faculty staffwork with Faculty staff►work in a specific field of studywork in a specific field of study
What motivated me to do What motivated me to do this this Chek Jawa studyChek Jawa study??
►CuriosityCuriosity►Answer questionsAnswer questions►gain experiencegain experience►Relevance to conservationRelevance to conservation
My My supervisorssupervisors1. Mr. N. Sivasothi 1. Mr. N. Sivasothi (Department of Biological Science, NUS)(Department of Biological Science, NUS)
2. Dr. Peter Todd 2. Dr. Peter Todd (Department of Biological Science, NUS)(Department of Biological Science, NUS) 3. Dr. Dan Rittschof 3. Dr. Dan Rittschof (Duke University)(Duke University)
Photo: Ria Tan
At the beginning…At the beginning…
►reading up various literatures reading up various literatures ►compilation of data and past observationscompilation of data and past observations►Discussions with my supervisors and expertsDiscussions with my supervisors and experts►Conducting of field surveysConducting of field surveys
Key pointsKey points of this session of this session1.1. High Biodiversity of Chek JawaHigh Biodiversity of Chek Jawa2.2. Mass death on January 2007Mass death on January 20073.3. How this study began?How this study began?4.4. What caused the mass death?What caused the mass death?5.5. How are the marine animals recovering?How are the marine animals recovering?6.6. What is the future of Chek Jawa?What is the future of Chek Jawa?7.7. Experiences of this projectExperiences of this project
Figure: Aerial photograph of Chek Jawa (squared in white) and its surrounding. Photo by Google Earth.
Kuala Johore
Salinity decreases
Heavy rainfall and flooding eventsHeavy rainfall and flooding events
►Intensified northeast monsoon in Intensified northeast monsoon in December and JanuaryDecember and January
►Flooding reported in different parts of Flooding reported in different parts of Malaysia and SingaporeMalaysia and Singapore
►Freshwater surge into Chek Jawa from Freshwater surge into Chek Jawa from Johor RiverJohor River
Chek Jawa
Enhanced runoff?
Narrowed Narrowed Johor Straits Johor Straits channel channel amplifies amplifies dischargedischarge
How How widewide is the mouth of Johor River is the mouth of Johor River
What may have contributed to the What may have contributed to the mass death? mass death?
1.1. incidents of low tideincidents of low tide2.2. amplified river output amplified river output 3.3. prolonged direct rainfall prolonged direct rainfall
Side view
Bird’s eye view
Cumulative rainfall data for Cumulative rainfall data for January 2007January 2007 taken from Changi Meteorological Stationtaken from Changi Meteorological Station
0
50
100
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350
400
450
500
.
1st 2nd 3rd 4th 5th 6th 7th 8th 9th 10th 11th 12th 13th 14th 15th 16th 17th 18th 19th 20th 21st 22nd 23rd 24th 25th 26th 27th 28th 29th 30th 31st
January 2007
Cu
mu
lati
ve
rai
nfa
ll (
mm
)
Prolonged Prolonged direct rainfall for about three days
Mass death first sighted
Incidence of low tide: Incidence of low tide: 11-14 January 200711-14 January 2007
1.51.616:00
1.34.415:00
1.12.314:00
1.12.313:00
1.22.412:00
14th
1.31.113:00
1.34.612:0013th
1.54.722:00
1.61.921:00
1.81314:00
1.624.113:00
1.410.712:00
1.37.411:00
12th
1.61.40:00
1.410.923:00
1.33.322:00
1.32.121:00
1.414.111:00
1.37.810:00
11th
Tide level (m)Hourly Rainfall (mm)HourJan-07
Amplified river output?Amplified river output?
Rainfall data to predict river water Rainfall data to predict river water level patterns for January 2007level patterns for January 2007
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.
1st 2nd 3rd 4th 5th 6th 7th 8th 9th 10th 11th 12th 13th 14th 15th 16th 17th 18th 19th 20th 21st
December 2006
Cu
mu
lati
ve r
ain
fall
(m
m)
0
50
100
150
200
250
300
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500
.
1st 2nd 3rd 4th 5th 6th 7th 8th 9th 10th 11th 12th 13th 14th 15th 16th 17th 18th 19th 20th 21st 22nd 23rd 24th 25th 26th 27th 28th 29th 30th 31st
January 2007
Cu
mu
lativ
e ra
infa
ll (m
m)
December 2006 January 2007
-1.5
-0.5
0.5
1.5
2.5
3.5
4.5
5.5
6.5
.
1st 2nd 3rd 4th 5th 6th 7th 8th 9th 10th 11th 12th 13th 14th 15th 16th 17th 18th 19th 20th 21st
December 2006
Riv
er
wat
er le
vel (
m)
River water-level data for December 2006, River water-level data for December 2006, taken from Johor River, Kota Tinggi.taken from Johor River, Kota Tinggi.
Key pointsKey points of this session of this session1.1. High Biodiversity of Chek JawaHigh Biodiversity of Chek Jawa2.2. Mass death on January 2007Mass death on January 20073.3. How this study began?How this study began?4.4. What caused the mass death?What caused the mass death?5.5. How are the marine animals recovering?How are the marine animals recovering?6.6. What is the future of Chek Jawa?What is the future of Chek Jawa?7.7. Experiences of this projectExperiences of this project
Conducting of field surveysConducting of field surveys
2.2. Transects surveys (once in 3 months)Transects surveys (once in 3 months)3.3. Monitoring of different groups of marine Monitoring of different groups of marine
animals (once in 2 months)animals (once in 2 months)
Sometimes we set off early…Sometimes we set off early…
…sometimes we go back late
T6T6
T5T5
T4T4
T3T3
T2T2
T1T1
N
Six transect linesSix transect linesT1
T2
T3
T4
T5
T6
T1
T5
T4
T3
T2
T6
Transect surveyingTransect surveying
Sometimes disasters do happen…Sometimes disasters do happen…
……af t e r a day’ s har d wor kaf t e r a day’ s har d wor k
0
5
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35
5-Jul-07
28-Sep-07
23-Dec-07
20-Feb-08
5-Jul-07
28-Sep-07
23-Dec-07
20-Feb-08
5-Jul-07
28-Sep-07
23-Dec-07
20-Feb-08
5-Jul-07
28-Sep-07
23-Dec-07
20-Feb-08
5-Jul-07
28-Sep-07
23-Dec-07
20-Feb-08
5-Jul-07
28-Sep-07
23-Dec-07
20-Feb-08
1 2 3 4 5 6
Transect
Nu
mb
er
of
tub
ewo
rms
Number of tubeworms between four periodsNumber of tubeworms between four periods
suggests recovery
Monitoring RecoveryMonitoring Recovery
•Specific fauna targeted
•Once every two months
•Record density
•Study changes
Monitoring Mussel BedsMonitoring Mussel Beds
A closer lookA closer look
Asian date mussel Asian date mussel
An invasive species
A friend or a foe?A friend or a foe?> can dominate and exclude some species by aggregation in high density
> may restrict growth of seagrass
> provide additional habitat
Dec 2007 vs Jan 2008Dec 2007 vs Jan 2008
suggests a possibility of mussel beds slowly being replaced away as recovery progresses
Latest updateLatest update from last Mondayfrom last Monday
Missing in actionMissing in action
Slowly but surely being eaten up?Slowly but surely being eaten up?
Real reason behind such an elimination is difficult to account for
More will be needed to give a scientific explanation
Carpet AnemonesCarpet Anemones
Photos: Ria Tan
•30 located and marked
•Shortest and longest diameter axis measured
•Tentacles counted
Not all things work!Not all things work!
Sea anemone morphology is variable Sea anemone morphology is variable
NOTNOT easy to study easy to study
What I’ve learnt from field What I’ve learnt from field applications from Dr Daphne Fautin?applications from Dr Daphne Fautin?
► anemones from tide pools anemones from tide pools contract when exposed to contract when exposed to airair
► can detach and movecan detach and move► difficult to determine sizedifficult to determine size► density differs density differs ► incorrect to correlated size incorrect to correlated size
with agewith age
Sand dollars Sand dollars
Sand stars Sand stars
Common sea stars Common sea stars
Button shells Button shells
Peacock Anemones Peacock Anemones
The sandbar before mass mortality is covered with several carpet anemones. After the mass mortality, the The sandbar before mass mortality is covered with several carpet anemones. After the mass mortality, the sand bar is almost barren of carpet anemones. These post mortality photographs were taken as part of sand bar is almost barren of carpet anemones. These post mortality photographs were taken as part of using photographs for comparison and also to monitor recruitment over time.using photographs for comparison and also to monitor recruitment over time.
12 January 2002
25 December 2007
16 August 2007
22 January 2008
Latest updateLatest update from last Mondayfrom last Monday
4 August 20084 August 2008
Still no anemones back on sand bar?
•long time to rebuild a population?
•Among the largest anemones
•live several centuries
•Replace themselves during their lifetime
•Reproduction is slow
Key pointsKey points of this session of this session1.1. High Biodiversity of Chek JawaHigh Biodiversity of Chek Jawa2.2. Mass death on January 2007Mass death on January 20073.3. How this study began?How this study began?4.4. What caused the mass death?What caused the mass death?5.5. How are the marine animals recovering?How are the marine animals recovering?6.6. What is the future of Chek Jawa?What is the future of Chek Jawa?7.7. Experiences of this projectExperiences of this project
LifeLife at Chek Jawa at Chek Jawa
What is the What is the futurefuture for for Chek JawaChek Jawa??
►Appears to be recoveringAppears to be recovering►Recruitment of larvae from nearby seeding Recruitment of larvae from nearby seeding
sitessites►Designation as protected area enhances Designation as protected area enhances
natural recoverynatural recovery►Marine life is vulnerable Marine life is vulnerable ►better understanding is essential to protect better understanding is essential to protect
Chek JawaChek Jawa
Key pointsKey points of this session of this session1.1. High Biodiversity of Chek JawaHigh Biodiversity of Chek Jawa2.2. Mass death on January 2007Mass death on January 20073.3. How this study began?How this study began?4.4. What caused the mass death?What caused the mass death?5.5. How are the marine animals recovering?How are the marine animals recovering?6.6. What is the future of Chek Jawa?What is the future of Chek Jawa?7.7. Experiences of this projectExperiences of this project
Some interesting Some interesting experiencesexperiences
Celebrating Celebrating ChristmasChristmas at at Chek JawaChek Jawa
On a more On a more seriousserious note… note…
Nearing Nearing submissionsubmission of report… of report…
Intense email discussions with Intense email discussions with various supervisors/experts etcvarious supervisors/experts etc
Corrections on my report draftsCorrections on my report drafts
How this project has enhanced my How this project has enhanced my undergraduate experienceundergraduate experience??
►Understand the meaning of Understand the meaning of researchresearch►Start questioning, analysing and exploringStart questioning, analysing and exploring►More questions than answersMore questions than answers►Walk out of comfort zone Walk out of comfort zone ►Some of best learning is Some of best learning is
by making mistakesby making mistakes
Friend who is inspired to do work at Friend who is inspired to do work at Chek Jawa too Chek Jawa too
What are my What are my future plansfuture plans ? ?
►Preparing to publish my findingsPreparing to publish my findings►Working on sea stars behaviour and ecologyWorking on sea stars behaviour and ecology► teaching after I graduate from NUSteaching after I graduate from NUS►Sharing experiences with my students Sharing experiences with my students
Find out Find out moremore about the project here about the project here
cjproject.blogspot.comcjproject.blogspot.com
Thank youThank you!!