Coastal Ecology

Associate Professor Shirley S. L. Lim

Shirley LimMy laboratory’s primary research thrusts are in the examination of ecological principles (e.g., optimal foraging, habitat adaptations, predator-prey interactions, niche partitioning) in wetland and coastal regions.  Extensive field studies on semi-terrestrial crabs and littorinid snails have been carried out by my research team at two off-shore islands (e.g., Pulau Hantu, and Tanjung Chek Jawa on Pulau Ubin), as well as at other coastal sites on mainland Singapore (e.g., sandy and mangrove shores along East Coast, Pasir Ris, Changi and Lim Chu Kang).

 

Recent Research

Learn more about our lab and recent research at http://ecolabnie.wix.com/shirley

 

Ocypodoid crab biology & ecology

ocypodoid-crab-biology
My lab is currently conducting research on the ecology of ocypodoid crabs (fiddler crabs, ghost crabs and soldier crabs), the most prominent wetland and coastal macrofauna. These bioenergetically significant crustaceans play an important role in the nutrient cycling and energy flow in coastal ecosystems, and may be used as indicators of eco-system disturbances.

Foraging ecology of fiddler crabs

Sexual dimorphism is distinct in fiddler crabs as the male has an enlarged cheliped that is used as a mate attractant and for combat with other males. Only the minor cheliped can be used for foraging!

uca-annulipes-male-femaleQuestions:

What are the foraging strategies used by the male fiddler crab to compensate for this apparent 'disadvantage'?

Do males feed faster to compensate?

When do males & females leave a foraging patch?

 

sl_foraging3

Fig. Mean scoop rate vs carapace width of Uca annulipes

For any given carapace width, female U. annulipes have a faster mean scoop rate than males

Conclusion:
Males, with only one cheliped with which to feed, do not compensate for handicap by feeding faster

sl_foraging4

Fig. Relationship between (a) dactyl length and (b) dactyl-pollex width, with carapace width in U. annulipes

For any given carapace width, although slopes and intercepts are not significantly different between the two sexes, males tend to have larger DL & DPW

ConclusionMales collect more sediment per scoop than females

 
Sequential patch depletion is studied by comparing the chlorophyll concentration in the surface sediment sampled from each patch.

patch-depletion1

patch-depletion2
Chl a] depletion in Uca annulipes’ first five feeding patches in bare & pneumatophore mangrove microhabitats
Male U. annulipes have higher critical threshold of [Chl a] in both PneuH & BareH

Conclusion: Males compensate by leaving a patch at a higher threshold of food density

Overall Conclusion:
Male U. annulipes does not compensate by feeding at a faster rate than females
Male U. annulipes compensates for the apparent ‘handicap’ of having only one cheliped with which to feed by:

  1. leaving a patch at a higher threshold of food density
  2. larger scoops of sediment per lift
  3. traveling shorter distances in between patches

 

Sexual selection in fiddler crabs

Are females attracted to larger males?
sexual-selection-in-fiddler-crabs

Female fiddler crabs' attraction to males that are magnified to different sizes is studied in the field.

Conclusion: Size of male is an important criterion in mate choice.

 

Burrow fidelity in fiddler crabs

On Pulau Hantu, two species of fiddler crabs, Uca annulipes and U. vocans are found in abundance on the lagoonal shore, with pure populations of U. vocans patchy in distribution and U. annulipes, the more abundant species.
burrow-fidelity1

burrow-fidelity2
Uca vocans
(seen here in these photographs) and U. annulipes were tracked for a few consecutive days in many low tide periods in the field in order to answer the above question.

Repeated re-emergence is indicated by the number of sticks next to the burrow.

Is there a difference in the burrow residency period between Uca vocans (a droving species) and U. annulipes (a non-droving species)?
 

Functional morphology of fiddler crabs

Do the mouthparts of Australian fiddler crabs from different habitats differ in their setation?

Relationship between number of spoon-tipped setae and carapace width in Uca perplexa & U. vomeris

fiddlercrabs1fiddlercrabs2

Conclusion:
Uca perplexa (a sandy habitat fiddler crab) has significantly more spoon-tipped setae than U. vomeris (a muddy habitat inhabitant).

 

Ocypodoid crabs as bioindicators

Density and spatial distribution of the burrows of the ghost crab, Ocypode ceratophthalmus, on the wave beaches at Pulau Hantu and East Coast Park were studied, in order to determine the potential of using the abundance of the crab as an indicator of human disturbance on Singapore beaches.

ocypode

Burrows of juvenile Ocypode ceratophthalmus in southern Thailand are typically catapult-shaped.
Is there a functional significance in this form of burrow architecture?

 Adeline Yong 

Can the ghost crab be a potential bioindicator for human disturbance on sandy shores in Singapore?

 

Littorinid snail biology & ecology

Littorinid ecology and behaviour also fascinate my students and me.  We have investigated the strange ‘head standing’ behaviour of periwinkles, compared the enzyme stability in various species of periwinkles when subjected to heat stress and looked at the effects of temperature and density on the aggregation behaviour of periwinkles. In addition, we are also interested in using these gastropods as bioindicators of coastal habitats; studies involving the use of gastropod mucus and radula as non-invasive methods with which to assess environmental pollution have recently started.

littorinid1

littorinid2

Amazing!  These Australian littorinids can withstand temperatures
of more than 40ºC! Does the ‘head stand’ behaviour help to
alleviate heat stress?

Two local littorinids also exhibit this peculiar ‘standing’ behaviour at Tanjung Chek Jawa, Pulau Ubin.

littorinid3

Is there a ‘cooling-off’ effect seen
in ‘standing’ Echinolittorina malaccana?
Why are there more ‘standing’
Echinolittorina vidua than
E. malaccana?

littorinid4

 

Predator-prey interactions in the local mangroves

Coming soon...

Current Ecolab Inhabitants

Coming soon...

Graduated Students (past 10 years)

Coming soon...

 

Selected recent publications from the Ecology Lab

  1. Su, T. L. & S.S.L. Lim. (in press) Niche partitioning in two syntopic mudskippers in a Singapore mangrove. The Raffles Bulletin of Zoology
  2. Lim, S.S.L., A.Y.P. Yong & J.H. Christy. 2016 Ontogenetic changes in diet and related morphological adaptations of Ocypode gaudichaudii. Invertebrate Biology
    DOI: 10.1111/ivb.12122.
  3. Su, T.L. & S.S.L. Lim. 2016. To flee or not to flee: characterising the differentiated anti-predatory responses of two mangrove crabs. Ethology, Ecology & Evolution
    DOI: 10.1080/03949370.2015.1129989
  4. Lim, S.S.L. & A.Y.P. Yong. 2015. Rapid population recovery of Ocypode ceratophthalmus (Pallas 1772) after an oil spill in Singapore. The Raffles Bulletin of Zoology 63: 270–278.
  5. Lim, S.S.L., G.M.S. Hew & A.Y.P. Yong. 2015. Constraints imposed by the major cheliped on burrow construction in the male fiddler crab, Uca annulipes (H. Milne Edwards, 1837). Journal of Crustacean Biology 35(2): 149–154.
  6. Lim, S.S.L. & Kalpana S. 2011. Maxilliped-setation adaptations to habitat and sexual dimorphism of feeding claw in Uca perplexa and U. vomeris. Journal of Crustacean Biology 31(3): 406–412.
  7. Yong, A.Y.P., S.S.L. Lim, A. Kaenphet & P. Tantichodok. 2011. Evidence of precision engineering in the excavation of Ocypode ceratophthalmus burrows in the west and east coasts of Thailand. Crustaceana 84 (5-6): 749–761.
  8. Lim, S.S.L., Yong, A.Y.P. & P. Tantichodok. 2011. Comparison of burrow morphology of juvenile and young adult Ocypode ceratophthalmus from Sai Kaew, Thailand. Journal of Crustacean Biology 31(1): 59–65.
  9. Lim, S.S.L. & J.A.C. Wong. 2010. Burrow residency and re-emergence rate in a droving species, Uca vocans (Linnaeus, 1758) and its sympatric associate, U. annulipes (H. Milne Edwards, 1837). Crustaceana 83(6): 677–693.
  10. Yong, A.Y.P. & S.S.L. Lim. 2009. The potential of Ocypode ceratophthalmus (Pallas, 1772) as a bioindicator of human disturbance on Singapore beaches. Crustaceana 82(12): 1579–1597.
  11. Lee, S.L. & S.S.L. Lim. 2009. Zonation and heat tolerance of three littorinid gastropods on the rocky shore of Tanjung Chek Jawa, Singapore. The Raffles Bulletin of Zoology 57(2): 551–560.
  12. Lim, S.S.L., R. Yeo, P.K.L. Ng & S.K. Tan. 2008. Front lines. [In] Ng, P.K.L., L.K. Wang & K.K.P. Lim (eds.) Private lives: An éxpose of Singapore’s mangroves (Pp. 91-114). Singapore: National University of Singapore.
  13. Lim, S.S.L. 2008. Body posturing in Nodilittorina pyramidalis and Austrolittorina unifasciata: A behavioural response to reduce heat stress? [In] Davie, P.F. & J.A. Phillips (eds.), Proceedings of The Thirteenth International Marine Biological Workshop, The marine fauna and flora of Moreton Bay, Queensland. Memoirs of The Queensland Museum – Nature 54(1): 339–347.
  14. Lim, S.S.L. & T.L. Tan. 2008. The use of infrared spectroscopy as a test for species- specific pedal mucus in gastropod molluscs – a comparative study in Moreton Bay and Singapore. [In] Davie, P.F. & J.A. Phillips (eds.), Proceedings of The Thirteenth International Marine Biological Workshop, The marine fauna and flora of Moreton Bay, Queensland. Memoirs of The Queensland Museum – Nature 54(1): 349–354.
  15. Lim, S.S.L. & C.K Lim. 2008. Running speed of Uca annulipes (H. Milne Edwards, 1837) and Uca vocans (L., 1758). Crustaceana 81(11): 1367–1380.
  16. Ng P.K.L., S.S.L. Lim, L.K. Wang & L.W.H. Tan. 2007. Private lives: An éxpose of Singapore’s shores. National University of Singapore. 212 pp.
  17. Lim, S.S.L. & Rosiah A. 2007. Influence of pneumatophores on the burrow morphology of Uca annulipes (H. Milne Edwards, 1837) in the field and in simulated mangrove micro-habitats. Crustaceana 80(11): 1327–1338.
  18. Lim, S.S.L. & M.M.S. Heng. 2007. Mangrove micro-habitat influence on bioturbative activities and burrow morphology of the fiddler crab, Uca annulipes (H. Milne Edwards, 1837). Crustaceana 80(1): 31–45.
  19. Lim, S.S.L. 2006. Fiddler crab burrow morphology: How do burrow dimensions and bioturbative activities compare in sympatric populations of Uca vocans (Linnaeus, 1758) and U. annulipes (H. Milne Edwards, 1837). Crustaceana 79(5): 525–540.
  20. Lim, S.S.L., Lee, P.S. & C.H. Diong. 2005. Influence of biotope characteristics on the distribution of Uca annulipes (H. Milne Edwards, 1837) and U. vocans (Linnaeus, 1758) (Crustacea: Brachyura: Ocypodidae) on Pulau Hantu Besar, Singapore. The Raffles Bulletin of Zoology 53(1): 111–114.

 

Selected recent conference presentations from the Ecology Lab

  1. Ng, J.J.J. & S.S.L. Lim. 2015. Different grooming and water-circulation rates in two fiddler crab species: evidence of adaptation to habitats? Presented at The Crustacean Society and International Association of Astacology (TCS–IAA) Mid– Year Meeting (19–23 July 2015), Sydney, Australia.
  2. Su, T.L. & S.S.L. Lim. 2015. To flee or not to flee: decisions of two genera of crabs in response to a series of predator model variants. Presented at The Crustacean Society and International Association of Astacology (TCS–IAA) Mid-Year Meeting (19–23 July 2015), Sydney, Australia.
  3. Yong, A.Y.P. & S.S.L. Lim. 2015. Switching or expanding the diet: feeding strategies of Ocypode gaudichaudii during ontogeny. Presented at The Crustacean Society and International Association of Astacology (TCS–IAA) Mid-Year Meeting (19–23 July 2015), Sydney, Australia.
  4. Su, T.L. & S.S.L. Lim. 2014. Anti-predatory behaviours employed by two common general of crabs in response to a mudskipper model. The XV Congress of the International Society for Behavioral Ecology (31 July–5 August 2014), New York City, USA.
  5. Yong, A.Y.P. & S.S.L. Lim. 2014. Plasticity of feeding behaviour of the painted ghost crab, Ocypode gaudichaudii at shores of different wave exposure. The XV Congress of the International Society for Behavioral Ecology (31 July–5 August 2014), New York City, USA.
  6. Lim, S.S.L., G.M.S. Hew & A.Y.P. Yong. 2013. Influence of the major cheliped on burrow morphology of the male fiddler crab, Uca annulipes. Presented at The Crustacean Society and Latin American Association of Carcinology (TCS–LAAC) Summer Meeting (7–11 July 2013), San José, Costa Rica.
  7. Goh, C.Y.Z, Lim, S.S.L., & A.Y.P. Yong. 2013. Food and sediment processing in the fiddler crab, Uca annulipes. Presented at The Crustacean Society and Latin American Association of Carcinology (TCS–LAAC) Summer Meeting (7–11 July 2013), San José, Costa Rica.
  8. Yong, A.Y.P. & S.S.L. Lim. 2013. Plasticity of feeding strategies of the ghost crab Ocypode gaudichaudii at shores of different wave exposure. Presented at The Crustacean Society and Latin American Association of Carcinology (TCS–LAAC) Summer Meeting (7–11 July 2013), San José, Costa Rica.
  9. Wong, Y.M. & S.S.L. Lim. 2011. Shell morphology and microstructure of two Singapore littorinids, Echinolittorina malaccana and E. vidua. Presented at X International Symposium on Littorinid Biology and Evolution (ISOLBE) 2011 (24–29 July 2011), St. Petersburg, Russia.
  10. Chin, P.P. & S.S.L. Lim. 2011. The effect of temperature on heart rate and Q10 of the ghost crab Ocypode ceratophthalmus. Presented at The Crustacean Society (TCS) Summer Meeting (6–9 June 2011), Honolulu, Hawai’i, USA.
  11. Lim, S.S.L., A.Y.P. Yong & J.H. Christy. 2011. In spite of its highly specialized claws, the ghost crab Ocypode gaudichaudii is not a picky eater. Presented at The Crustacean Society (TCS) Summer Meeting (6–9 June 2011), Honolulu, Hawai’i, USA.
  12. Ng, G.H. & S.S.L. Lim. 2011. A unique crustacean community adapted to extreme salinity fluctuations in the vicinity of an urban Singapore concrete drain. Presented at The Crustacean Society Summer Meeting (6–9 June 2011), Honolulu, Hawai’i, USA.
  13. Ng, K.L.J., S.S.L. Lim & H.T. Shih. 2011. Is there plasticity in mouthpart and gastric mill adaptations to different habitats in Uca formosensis? Presented at The Crustacean Society (TCS) Summer Meeting (6–9 June 2011), Honolulu, Hawaii, USA.
  14. Su, T.L.T. & S.S.L. Lim. 2011. Effect of mudskipper predation on crustacean abundance and biodiversity in a Singapore mangrove. Presented at The Crustacean Society (TCS) Summer Meeting (6–9 June 2011), Honolulu, Hawai’i, USA.
  15. Yong, A.Y.P. & S.S.L. Lim. 2011. Responsiveness of Ocypode ceratophthalmus populations in Singapore beaches to environmental stress. Presented at The Crustacean Society (TCS) Summer Meeting (6–9 June 2011), Honolulu, Hawai’i, USA.

Coastal Ecology Lab, NIE/NTU