Indonesia’s Coastal Ecology

Liam HammerDepartment of ScienceGlobal Jaya International School

A Clicker Case investigating the ecology of the waters around Java.

Goals

• To compare the health of two coral reefs• To examine and hypothesis why a particular

beach is changing (after building a pier and planting mangroves)

• To explain why removal an organism from a food chain can be problematic : (Sea Urchins – Tanjung Lesung experience

• Mangrove replanting ?• Sea grass ? & Turtles ?

Wallace described the island of Java in 1861:“Taking it as a whole, and surveying it from every point of view, Java is probably the very finest and most interesting tropical island in the world. (Wallace, 1869)

Part I – Location of the 1000 Islands

Pulau Seribu or the thousand islands actually only number 110. They are a band of low lying islands just north of the coast of Jakarta, up to 80kms away. The potential of these islands was recognized in 1979 when they were listed to become protected.

Next to Jakarta, a city of almost 10 million1 people on the island of Java, one of the most densely populated islands in the world has it’s challenges. Although the coral islands are not the best in Indonesia, (those are more likely in Papua, Bali or Sulawesi), very few countries in the world have such excellent marine resources so close to a capital city. (Kvalvagnaes and Halim 1979b)

CQ#1 – What sort of potential did the Indonesian government see in the 1000 islands ?

A. Recreation for foreign and domestic tourismB. Food benefits for local peopleC. Commercial benefits for visiting fishermanD. Combination for all three

CQ#2 – What sort of problems does the 1000 islands face?

A. Poor fishing practices such as dynamite fishing, overfishing, over exploitation by commercial fisherman

B. Pollution; sound and waves, trash accumulation and oil spills, rainwater runoff from residents and proximity to Jakarta

C. Careless tourism; dumping of rubbish, trample damage on corals, removal and collection of coral, shells and organisms for domestic fish tanks

D. A combination of all three

Human Impact : building a pier

Palau Semak Daun, is about a 30 minute boat ride from Palau Pramuka, the capital island of the regency. It is a popular day trip destination for local tourism, as it is uninhabited, with the exception of a single house for the caretaker. Prior to 2007

2007 : work has commenced on building a boat pier to make the island more accessible, currently boats have to anchor just off the beach.

2008 : the pier and a small shelter have been completed.

2011 : Four years later the shelter is looking slightly run down.

CQ#3 – What are the main differences between the two pictures taken four years apart ?

A. The tree is no longer in the picture. B. The shelter is falling over.C. The beach has about 5 of metres extra sand.D. The dark patch of seagrass has moved

forwards.

Answer to CQ#3 – What are the main differences between the two pictures taken four years apart ?

C. The beach has about 4-5 metres of extra sand.Count the number of pier pylons visible in the pictures. Notice the seagrass (dark patch) is still in the same place relative to the shelter and pier, but is now almost on the edge of the shoreline. The differences in the tide levels can account for a little of this, but not all. The tree in the first picture, is not about 5 metres behind the location of the photographer.

CQ#4 Suggest a reason for the additional sand on the beach

A. The owner, caretaker of the island or the boat operators brought some sand from somewhere else and dumped it here.

B. The building of the pier has resulted in changes in ocean currents and caused additional sand to pile up here.

C. Some natural processes are at work here and it is nothing to worry about.

D. The planting of the mangroves on the other side of the pier resulted in changes in currents that cause sand to build up here.

CQ#5 – Removing dangerous or annoying creatures from an ecosystem is a good idea.

A. Yes, people need to be safe to be able to use the environment.

B. No, it is never a good idea to mess with food webs.

C. Depends on the situation.

Sea UrchinsSea Urchins (Diadema antillarum) are a type of echinoderm, they have many long defensive spines that can easily pierce human skin and break off into hands or feet touching them leaving a painful infected wound. As a result, they are unpopular with many tourists, despite being considered a culinary delicacy in some countries.

Sea Urchins are marine grazers, they eat algae off the surface of the corals. They are also are a rather tolerant species and are able to populate areas that are more damaged or disturbed than pristine areas. Thus they tend to be more common in those areas.

CQ#6 – Why are Sea Urchins more commonly found on degraded coral reefs ?

A. They prefer it there.B. Less predators.C. Less competition. D. They need pollution to survive

Tanjung Lesung :Sea Urchins Management

Tanjung Lesung is an area about 160kms South West of Jakarta, in the busy Sunda Straights. There is a large hotel/resort that has a small coral reef area in a protected bay. Tourists complained about the sea urchins, so the management of the resort, which had been facing hard times due to the fact they were so far away from Jakarta, hired some divers to spend a week clearing off every single sea urchin and removing them from the reef.

CQ#7 – Suggest possible results of managements decision to remove all the sea urchins.

A. Tourism increased because there was no more sea urchins to sting unwary people.

B. Some larger apex predators starved to death because of the lack of sea urchins.

C. The sea urchins returned anyway.D. The coral reef become overrun by algae since

there were no sea urchins to graze on it, and become damaged as a result.

CQ#8 – Removing dangerous or annoying creatures from an ecosystem is a good idea.

A. Yes, people need to be safe to be able to use the environment.

B. No, it is never a good idea to mess with food webs.

C. Depends on the situation.

BIBLIOGRAPHY1. Wallace, A.R. 1869. On the zoological geography of the Malay archipelago. J.Linn. Soc.

London 2. Wallace, A.R. 1869. The Malay archipelado. London: MacMillian.3. Whitten , Tony. Soeriaatmadja, Roehayat Emon. Afiff, Suraya. 1996.Volume II:The Ecology of

Java and Bali. The Ecology of Indonesian Series, Periplus Editions (HK) Ltd. pgs 345-384, 756 ,780-782

4. Setiawati, Indah. After census city plans for 9.5 million The Jakarta Post, Jakarta .08/28/2010 http://www.thejakartapost.com/news/2010/08/28/after-census-city-plans-95-million.html Date last accessed 28/09/2011.

5. Long Spined Black Sea Urchin Report

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SLIDE CREDITS• Unless explicitly indicated otherwise below, all images in this Powerpoint Presentation™ are the creation of the case author, L .Hammer.• Slide 1

– Description: Photo of a Photo of Pulau Semak Daun– Author: Abbey Budiman– Source: Global Jaya International School

• Slide 3– Description: Location of the thousand islands– Source: Google Earth– Clearance: Licensed according to terms of Creative Commons Attribution-Share Alike 3.0 Unported.

• Slide 4– Description: Riparian zone in Grand Teton National Park– Author: Daniel Mayer– Source: Wikimedia Commons; link– Clearance: Licensed according to terms of Creative Commons Attribution-Share Alike 3.0 Unported.

• Slide 9– Description 1: Photo of Workers building a pier on Pulau Semak Daun– Author: Liam Hammer– Source: Global Jaya International School– Description 2: Photo of boat anchored on the beach of Pulau Semak Daun– Author: Liam Hammer– Source: Global Jaya International School

• Slide 10– Description: Photo of a Photo of Pulau Semak Daun dated 2008– Author: Liam Hammer– Source: Global Jaya International School

• Slide 11– Description: Photo of a Photo of Pulau Semak Daun dated 2010– Author: Liam Hammer– Source: Global Jaya International School

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