Timor-Leste Marine Science Training Handbook

Timor‐Leste Marine Science Training Handbook

Last updated March 2016

Contents 1 THE NATURAL HISTORY OF TIMOR‐LESTE ...... 2 1.1 Timor‐Leste ...... 2 1.2 The importance of the Coral Triangle ...... 3 1.3 Climate of Timor‐Leste ...... 4 1.4 Conservation in Timor‐Leste ...... 4 2 BLUE VENTURES CONSERVATION IN TIMOR‐LESTE ...... 5 2.1 Blue Ventures’ aims and objectives ...... 5 3 INTRODUCTION TO TROPICAL MARINE ECOSYSTEMS ...... 6 3.1 Coral Reefs ...... 6 3.2 Seagrass beds ...... 10 3.3 Mangroves ...... 12 4 THREATS TO TROPICAL MARINE ECOSYSTEMS ...... 14 5 TROPICAL MARINE INVERTEBRATES ...... 16 5.1 Sponges ...... 16 5.2 Cnidarians ...... 16 5.3 Molluscs ...... 17 5.4 Echinoderms ...... 17 5.5 Tunicates ...... 18 6 INTRODUCTION TO FISH ...... 19 6.1 Introduction to common fish families ...... 19 7 KEY MARINE GROUPS ...... 25 7.1 Turtles ...... 25 7.2 Marine mammals ...... 25

1 THE NATURAL HISTORY OF TIMOR‐LESTE

1.1 Timor‐Leste Timor is the largest of the Lesser Sunda Islands at the Eastern tip of the Indonesian archipelago in Southeast Asia. The island is split between Timor‐Leste in the east and the Indonesian province of East Nusa Tenggara in the west. Timor‐Leste has a landmass of just over 15,000km2, including offshore islands Ataúro and Jaco as well as Oecusse, an exclave situated in Indonesian portion of Timor. The population is estimated at about 1.3 million with a growth rate of approximately 2.5% a year.

Located in the Coral Triangle, Timor‐Leste boasts high levels of species diversity among reef fish and corals, and its reefs are relatively unexplored compared to those of neighbouring areas such as Australia and Bali. Terrestrial biodiversity, similar to other island nations that have been separated from nearby continents for a significant period of time is also interesting with Timor possessing a number of endemic bird and reptile species, including the Timor python.

Map of Timor‐Leste showing districts and nearby islands (Source: UN)

1.2 The importance of the Coral Triangle Nowhere else on the planet can you find the levels of marine biodiversity present in the 6 million km2 of the Coral Triangle, which is spread across six countries. Due to the combined factors of tropical light, warm waters, and strong oceanic currents and upwellings in an area with great topographical variation, the range is considered the epicentre of global coral reef biodiversity.

More than three quarters of all known coral species occur here, and although endemic marine species are rarer than terrestrial ones, due to the indiscriminate spawning methods used by most fish, coral and invertebrate species, there are relatively high numbers found in the Coral Triangle; 15 species of coral and at least 235 species of fish that are considered endemic or “locally restricted”. Six out of the world’s seven turtle species are present, as well as mammals; whales, dolphins and endangered dugongs, and elasmobranchs; sharks and rays.

Despite the wealth of marine life found here, more than 250 species are classified by IUCN as “threatened with extinction”, little surprise given the combined pressures of pollution, destructive fishing methods, rising sea temperatures and ocean acidification.

Tourism plays an important role in the coral triangle, with opportunities for alternative livelihoods to relieve fishing pressures being one of the key strategies of conservation groups the world over. 120 million people depend on the resources of the Coral Triangle for their food and livelihoods, and while the area is renowned for its productivity the pressures of such a large and continuously growing population are huge.

Map showing the area known as the Coral Triangle (Source: WWF)

1.3 Climate of Timor‐Leste Located 953km from the Equator and 650km from the coast of Australia, Timor‐Leste has a tropical climate, hot and humid year round with wet and dry seasons rather than summer and winter. The temperature hovers around 30°C throughout the year, with moist winds coming from the northwest from November to May, and dry winds coming from the southeast the rest of the year. Fluctuations in temperature are more likely to come at higher altitudes or directly next to the sea. Ataúro, the current Blue Ventures site in Timor‐Leste, is located 25km north of Dili. The site is rugged and topographically diverse, and can feel very hot when becalmed and cool when the winds blow.

In‐water temperatures vary between 24°C and 28°C throughout the year depending on where the currents are flowing from and the levels of rainfall. Visibility is usually good year‐round off Ataúro, but can vary in off the mainland due to rainfall carrying sediment from the mountainous interior into coastal waters via the country’s many rivers. 1.4 Conservation in Timor‐Leste As a young nation, Timor‐Leste’s management of its natural resources is in a nascent and critical stage. The country relies on a sovereign petroleum fund for much of its national spending but revenues are decreasing annually and there is widespread acceptance that much greater levels of economic diversification are required in order to tackle any future shortfalls.

Timor‐Leste has a total of 50 protected areas, the majority of which are currently at the proposal stage. The largest and best supported protected area, and the only one with a marine component, is Nino Konis Santana National Park in the east of Timor‐Leste. A further 120,000 hectares of seascape are earmarked for protection, including much of the area surrounding Ataúro, but governmental resources for conservation are limited, and there are few civil society organisations focused on conservation with permanent activities in Timor‐Leste.

Despite the presence of these obstacles, Timor‐Leste has enshrined the conservation and protection of natural resources in its constitution, and recognises that sound management of coastal and marine resources are essential to guide sustainable livelihoods, development and poverty alleviation.

With a wealth of comparatively untouched terrestrial and marine natural resources, Timor‐Leste has an excellent opportunity to establish itself as a destination that showcases the splendour of the Coral Triangle along with a ruggedly beautiful landscape with a rich colonial and cultural history. Tourism in the Coral Triangle is worth US$16 billion annually, and although it can be an economic boon to such countries, bringing money into local communities via a multitude of vectors, it can also increase pressures on the environment if not managed carefully. Blue Ventures’ goal in Timor‐Leste is to design a financially sustainable ecotourism project that generates economic benefits for local communities, incentivising those communities to manage their local marine resources in an effective and sustainable matter. By building capacity at community level, efforts for long term marine management at a national level are supported, further safeguarding them for future generations.

2 BLUE VENTURES CONSERVATION IN TIMOR‐LESTE

2.1 Blue Ventures’ aims and objectives The Blue Ventures model is adapted for best use wherever we work, but loosely follows this pattern:

Education

 Education in marine conservation and research for volunteers from all around the

world  Education for local communities in marine conservation and ecotourism through open days and workshops  Education in schools and universities in the

UK promoting marine conservation and sustainable development

Research

 Trained staff and volunteers conduct monitoring and baseline survey work of key areas in the country  Data gathered used by Blue Ventures alongside local people and the scientific

community to develop a management strategy for the coastal region

Conservation

 Marine habitats are better understood and consequently better protected through increased awareness  Local villages and fishing communities benefit from increased protection of coastal

zone, effective marine management, and alternative livelihoods being generated

Working from Dili and Ataúro, BV will strive to implement an ecotourism programme that will highlight the need for education, research and conservation to volunteers, while at the same time immersing them in our efforts to implement our model.

3 INTRODUCTION TO TROPICAL MARINE ECOSYSTEMS

Coral reefs are one of the most well‐known and recognisable ecosystems world‐wide and a huge focal point for global biodiversity protection efforts. However, their success in many areas is dependent on interactions with two other equally valuable yet lesser known ecosystems, areas that are also constantly under increasing climatic and anthropogenic pressures. Seagrass and Mangrove ecosystems are tropical marine ecosystems that, together with coral reefs, form a tripod with each ‘leg’ interacting with the others, providing support and being supported. All are shallow water ecosystems and their presence or absence is dependent on prevailing local conditions; coral reefs are most prevalent in seaward areas, seagrass in more protected waters and mangroves in intertidal areas. Blue Ventures expeditions will focus on documenting and assessing each of these habitats, and their associated fauna. In conjunction with social, economic and fisheries knowledge this information will form an important part of advising community based management in the future. 3.1 Coral Reefs Overview Coral reefs comprise less than 0.25% of the ocean floor, an area of only 284,300km2, yet it is estimated that more than 80% of marine species are in some way dependent on them. Home to a quarter of all known marine species, reefs include more than 5,000 fish species and up to 2 million species overall. Coral reefs are the most productive ecosystems in the marine environment and are able to fix large amounts of carbon dioxide, making them vital to the future health of the planet. Structure of coral reefs Most of the structure of a coral reef consists of the cumulative calcium carbonate deposits of reef‐ building (hermatypic) corals. The living creatures are restricted to a thin surface layer and are known as polyps and each individual coral polyp usually forms part of a colony. Corals feed on plankton but this only makes up about 10% of their diet; the rest comes from a symbiotic partnership with a type of photosynthetic algae known as zooxanthellae. The algae, housed safely in the epidermal layer of the polyp, uses light and waste products from the polyp to provide the rest of the coral’s needed energy in the form of an excess of photosynthesised material. Each species of coral grows in a different way and as the differences in polyp structure can be almost indecipherable between them,

Growth forms: fast‐growing branching coral, and slower, hardier encrusting coral and it is these growth forms that we teach and monitor.

Other organisms which contribute to the makeup of the reef include non‐reef‐building corals, numerous sessile and mobile invertebrates and a variety of different types of algae. Coral reefs are ever‐changing, constantly evolving ecosystems, delicately balanced and vulnerable to outside

factors. The structure of a fish population on a reef is a determining factor in the health and structure of a coral reef with herbivores playing an important grazing role with their removal often cited as the first stage in the degradation of a coral reef. Factors controlling coral reef distribution Coral reef distribution is restricted by the factors that limit coral productivity and survival. The most important factors that control coral reef distribution are light, temperature, salinity, nutrient levels and sediment. Reefs grow in patterns across the world that seem strange unless all these factors are taken into account.

Light Light on a reef is an essential resource with fierce competition for space among corals and the faster‐growing algae with both reliant on sunlight for growth. The deeper the reef, the less intense the light, and coral species grow in different forms at different depths to reflect this.

Temperature Most tropical reef‐building corals cannot tolerate prolonged periods of temperatures outside a very narrow range, generally accepted to be between 23 and 29°C, although some corals can endure higher temperatures for short times before damage occurs (see: Coral Bleaching).

Salinity Reefs are only found in seawater, and are so intolerant of fresh water that they will not even form near large river mouths (see also: Sediment).

Nutrients Coral reefs thrive in clear rather than nutrient‐rich waters. Human influence, in the form of nutrient‐ heavy river run‐off from some agricultural and aquacultural practices boosts the growth of algal species. Outcompeting slower growing corals, algal growth reduces the amount of light available to them and eventually smothers them.

Sediment Reefs do not form in areas with high levels of suspended sediment; light levels decrease in such areas, and sediment can abrade or smother a reef if it is not washed away into deeper waters. Where suspended particles settle onto the substrate it can also prevent coral recruits from settling, thus inhibiting the reef’s further growth. Reef development Coral produces planktonic larvae, called planulae, in order to propagate over large distances through ocean currents reaching distant reefs to settle on and grow. Upon landing upon a suitable substrate, the planulae attach themselves to the reef and form new polyps; a process called recruitment. Some sites are more advantageous than others, depending on the substrate; a patch of reef that appears to have been painted pink indicates the presence of crustose coralline algae (CCA), which acts as the cement of the reef. Coral recruits which are situated on CCA are hardier and more likely to survive and reproduce, growing into a large colony that can support life. Depending on where they settle relative to land, one of three reef types forms. Charles Darwin postulated that these three formations are just three stages of reef development as reefs form and land subsides, as shown below:

Fringing Coral forming on or near the coast creates what is known as a fringing reef. Shallow waters and a substrate which slopes gently out to deeper waters create conditions which allow large, continuous reefs which follow the coastline and are typically only separated from it by a narrow stretch of water.

Barrier Barrier reefs are also continuous, and tend to run parallel to the closest land, but are removed from it by a large, often quite deep lagoon. The land here has subsided to the point where there is no connection between land and reef but their positions relative to each other.

Atoll An atoll is what is left when all land has subsided and the coral reef has continuously built on itself to maintain its position. Usually round or oval having formed around a land mass, they have a central lagoon and sometimes islands at different tidal levels.

Regardless of how they formed and where, most reefs share a basic zonation and structural pattern; the area between land and the reef crest is known as the reef flat, and the reef seawards from the reef crest known as the fore reef, before walls (steeper in some areas than others) drop off into much deeper waters.

Back reef The back reef, behind the reef crest, is protected from ocean swell but experiences limited water movement making this section of the reef highly variable in temperature and salinity, so whilst many invertebrates flourish in these protected waters, coral growth is limited.

Reef crest This area takes the brunt of the wave action on the reef, and protects the back reef and any seagrass lagoons present from the constant churn of water and sediment of the fore reef and beyond. Often exposed for long periods at a time the crest can be home to fast‐growing branching corals where wave action is limited, or virtually none where it is constant and severe.

Fore reef Also known as the buttress zone for its distinctive structure, fore‐reefs often grow in a formation known as “spur and groove”, with channels of sand separated by spires and ridges of coral, giving it an instantly recognisable pattern from the surface. Designed to dissipate wave energy and drain away excess sediment, the fore‐reef is a highly diverse area, with abundant resources in terms of oxygen and sunlight, but occasional bouts of turbulence from storms or worse. Here thrive the massive and encrusting corals, slow‐growing but sturdy, and any fish whose idea of perfection is to live in shallow water, hide in a hole when predators come by, and eat algae all day long – and the predators.

Deeper reef As the reef slopes down to greater depths the available light decreases, as does wave action. If the conditions on the patch where coral recruits have landed are conducive to that coral’s needs, it will grow, and possibly flourish, particularly if it can grow in a formation which makes the most of its current conditions. As depths exceed 40m, reef‐building corals give way to sponges, gorgonians (sea whips and sea fans) and the non‐reef‐building (ahermatypic) corals, and the eye of the recreational diver looks down wistfully, before ascending to safer and brighter depths.

3.2 Seagrass beds Despite first appearances, seagrasses are actually flowering plants rather than a type of seaweed. There are more than 70 extant species of seagrass; whilst their meadows may not appear to be particularly diverse to the casual eye and tend to be overshadowed by more exciting and charismatic biomes, they are in reality one of the most productive types of marine ecosystem worldwide, and thus are extremely valuable.

An estimate from the Smithsonian Institute recently claimed that one acre of healthy seagrass can support 40,000 fish and 50 million invertebrates. In one year, one acre of seagrass fixes the same amount of carbon a typical car emits over a trip of 3,860 miles (6,212 km), while at the same time producing nearly 15 million litres of oxygen through photosynthesis. If you need charisma to care, consider that they are also the primary habitat of dugongs (vulnerable), manatees (vulnerable) and green turtles (endangered), and are also the first stage nursery for many species of reef fish.

Seagrass diversity Seagrass beds can be found in all of the world’s oceans and grow along the shores of all continents except Antarctica.

Seagrass meadows in temperate waters however, tend to be less diverse than those of the tropics where it is not uncommon to find upwards of ten species in a small area, particularly in the Indopacific.

The adjacent key describes some common Indopacific seagrass species with species from genera Thallassia, Enhalus and Syringodinium being the most common constituents of Indopacific seagrass beds.

Blue carbon The carbon locked up in the world’s oceans and coastal ecosystems is collectively known as blue carbon. Stored in a variety of organic forms from living biomass to coastal sediments, blue carbon is a sizeable and critical component of the global carbon cycle. Seagrass meadows store an estimated 10‐18% of all oceanic carbon despite only accounting for 0.1% of the world’s seafloor. Whilst some of this carbon is held in the living biomass of the seagrass, the vast majority (more than 90%) is sequestered in the organic sediments beneath. If a seagrass meadow is lost, the carbon within the sediments below is no longer stored in an inert form and the meadow becomes a potential emitter of carbon dioxide instead.

There are very few shallow coastal regions in the world that do not play host to at least one type of blue carbon ecosystem. The above map outlines the estimated global extent of mangroves, seagrass meadows and salt marshes (a third, equally important coastal carbon store) The Coral Triangle has an abundance of all of them along with exemplary coral reef coverage.

The surveys of Timor‐Leste’s seagrass meadows completed each expedition mark the beginning of a project aimed at assessing the state of seagrass resources and working with communities to conserve them and their most threatened inhabitant, the dugong (Dugong dugon), (see: Marine mammals). Seagrass beds are continually threatened through development, dredging and destructive fishing methods, and a global lack of awareness of their importance is a key factor in this.

3.3 Mangroves

Mangrove adaptations Mangroves are among the most fascinating organisms in the botanical world, living in harsh saline environments that would quickly kill other plants and trees. As salt‐loving organisms (facultative halophytes), each species has developed various adaptations to the conditions of the coastal zone. Mangrove ecosystems are restricted to inter‐tidal and estuarine areas with a clear progression of species, each with differing survival strategies progressing from low to high tide and beyond.

Prop roots Species of mangrove found at low water are often those exposed to the greatest level of water movement and thus have significant adaptation to ensure they remain rooted in place. Prop roots are roots that suspend mangrove trees above the water line, stabilising and protecting the main body of the plant.

Salt intake Whilst described as 'salt loving', all species of mangrove have a number of adaptations to exclude and excrete the salt in the water they uptake. All mangrove roots are impregnated with suberin, a compound that acts as a selective barrier, excluding up to 97% of salt at the point of intake. The salt intake still in excess of what is required by the plant is excreted as salt crystals on the underside of the leaves by many species of mangrove.

Pneumatophores One of the most striking features of mangroves stands are the swathes of upward facing pneumatophores found in dense aggregations around the base of trees exposed at low tide. Also known as ‘finger roots’, they act as breathing tubes for a tree. Growing roots that emerge from the soil into the atmosphere enable a tree to breathe because mangroves sediments are extremely oxygen poor.

Vivipary Mangroves produce live young; buoyant seedlings known as propagules germinate on their branches and, when mature, drop into the water to drift on currents and create new stands of trees once a suitable environment has been reached.

Mangroves support a phenomenal number of organisms both above and below the waterline. Birds and insects, numerous reptiles and invertebrates in droves inhabit their thick leaves above land, and such habitats are decreasing in their abundance on a global scale. Beneath the surface though, lies an equally diverse and little seen underwater wonderland. Mangrove roots play host to a wealth of anemones, tunicates and sponges which thrive on in waters rich with plankton and suspended organic matter.

Mangrove roots act as a secondary nursery for many species of reef fish during the transition between juvenile and adult life stages. The small spaces between roots provide shelter from predators, and the richness of planktonic and invertebrate life provides an ample source of sustenance.

Mangroves grow in formations known as mangals, and new mangals can form from settled propagules tangling together in shallow, sediment‐heavy waters; once established they begin to accrete sediment and new islands can spring up relatively fast. Conversely, when mangroves are removed from a coastline their protection from erosion is also lost; in the last decade alone 35% of the world’s mangroves has been destroyed, either for wood to build or burn, for land clearance or even just to improve the view for tourism. Blue carbon Mangroves, along with seagrass meadows and salt marshes, are part of the blue carbon ecosystem and are responsible for approximately 15% of marine carbon storage worldwide. Mangroves are resilient to climatic disturbances such as floods and cyclones but are arguably under the greatest threat of any tropical marine ecosystem; coastal development, shellfish fisheries, and many mangrove species’ utility as a building material and firewood are all significant causes of mangrove habitat loss in the last 50 years.

4 THREATS TO TROPICAL MARINE ECOSYSTEMS

Coastal marine ecosystems across the world face a host of threats. Some are climatic and naturally occurring, others are climatic but amplified by human activity; an ever increasing proportion are a direct result of human activity. Timor‐Leste is at as great a risk as any other coastal state from climatic threats, amplified or otherwise, but as an emerging nation still forming a consensus on sustainable development, there is hope that preventative action can be taken against some direct human impacts. Coastal development Coastal zones around the world are being developed at a phenomenal rate in an attempt to exploit their economic potential, sometimes with very little thought spared for sustainability or damage to the environment. Mangroves are cleared to make room for new developments and seagrass beds are dredged to create channels deep enough to allow ships close to shore. Carbon rich sediments, released by the removal of these habitats, often impact local coral reefs by reducing water clarity, with long term climatic ramifications resulting from the re‐entry of the previously sequestered carbon back into the local carbon cycle. Fishing The gross value of Timor‐Leste’s fisheries output was last published in 2004 at nearly US$6 million, only 1.25% of the country’s GDP, although reliable data are rare and records kept during the Indonesian occupation may not be accurate or well‐maintained. Most people are subsistence fishers, only taking what they need to feed themselves and make a small living. This type of fishing occurs mostly on shallow reefs, as currents make fishing in deep waters in a small boat dangerous. In some areas, local fishers use small‐meshed nets and/or poisons on the reefs, both of which are damaging, and boat anchors are used at different locations daily, spreading impact damage across wide areas. Many of the fish available for sale locally are reef fish, including important herbivores such as parrotfish, whose removal can have serious consequences for reef health. Tourism Tourism can be a blessing and a curse to developing nations, with the potential for quick profits overshadowing the prospective damage caused by unsustainable or unscrupulous practices. From boats anchoring on reefs to guides feeding marine life to attract the charismatic species sought by tourists, without robust and widely agreed upon guidelines, tourism can, in a very short time, have a negative impact on marine ecosystems. Cruise ships are frequent contributors to plastic waste problems in the marine environment, and even the sunscreen that visitors are encouraged to put on several times a day contains chemicals that are harmful to coral. Snorkelers standing on reefs or molesting sea life and divers taking home souvenirs or sitting on corals to have their photo taken are all scenarios we have witnessed first‐hand, and these are typically done by people with no idea that they are damaging the reef. Climate change As we have observed over recent years, global weather patterns are greatly affected by climate change and the impacts humans are having on the environment. El Niño and La Niña events over the last two decades have become more severe, with El Niño events in 1982, 1998, 2005 and 2010 causing mass devastation to coral reefs across the tropics (see: Bleaching). Tropical storms are deleterious to any type of coastal ecosystem, with the storm surges generated by even small hurricanes capable of pulverising reefs, gouging up vast tracts of seagrass and uprooting stands of mangroves. In addition to the clearing of these coastal ecosystems by storms, events in the

aftermath can often prevent them from regaining a foothold if faster plants or algae move into the breach instead (emphasising the importance of herbivorous fish). The timescales for the proliferation of tropical marine ecosystems are often measured in decades rather than years, and increasingly frequent large storms or periods of several storms in quick succession can often seriously inhibit ecosystem recovery. Temperature When temperatures in the water exceed a coral polyp’s optimum level for a sustained period of time the colony undergoes a process known as bleaching; symbiotic zooxanthellae, coral’s main source of energy as well as what gives them their distinct colours, are expelled from the coral, leaving the polyp translucent and malnourished, characterised by a distinctive white appearance. The theory behind this A massive coral showing signs of bleaching process is that it is an adaptation that clears space for other, more heat‐tolerant species of zooxanthellae to propagate within the colony, and thus be more successful in the higher temperatures. If the temperature returns to previous levels in time, then the original algae may return to the coral. If not, the coral generally dies, leaving only its skeleton. With global ocean temperatures on the rise, and coral reefs restricted to the surface layers of water that are most affected, the projected ramifications are not good. Ocean acidification Ocean acidification is the ongoing decrease in the pH of the world’s oceans, and poses a very real threat to any and all organisms that build a shell or skeleton out of calcium carbonate. Increased levels of carbon dioxide absorbed by the oceans globally have led to a 30% decrease in the pH of seawater since the 1800s. Reef building corals are affected particularly harshly, as greater acidity dissolves the coral's calcium carbonate skeleton and at the same time reduces the amount of carbonate available to the coral to draw out of seawater to use in growth and rebuilding. Ocean acidification is almost certain to result in a reduction in diversity of all calcifying organisms worldwide; some models cite ocean acidification as a major cause of future coral reef die‐off events, easily as serious as coral bleaching.

5 TROPICAL MARINE INVERTEBRATES

A spineless majority consisting of 95% of the 1.4 million recorded species are classed as invertebrates. Of this number, 1.2 million of these species are Arthropods; the crustaceans, insects, spiders and other creatures possessing an exoskeleton and jointed legs. In the marine environment, invertebrates occupy a huge diversity of size, form and function; from the microscopic polyps of numerous reef building corals to the giant squid. Invertebrates that can be found in tropical waters include representatives of the oldest still‐extant group of multi‐cellular organisms on Earth, and some of the most prolific architects on the planet. Whilst some tropical marine invertebrates are small, cryptic or concealed and need a large amount of time and energy to find in the first place, we focus our survey efforts on the conspicuous species which provide an indicator of the health and status of a reef. 5.1 Sponges Sponges are the oldest known living group of multi‐cellular organisms, and their longevity can likely be attributed to their exceedingly simple physiology and life strategy. They have a simple body plan, drawing water through tiny inhalant pores called ostia and filtering it of bacteria and food particles before pumping it out through larger exhalant holes. A large sponge can cycle through up to 20,000 times its volume in a single 24 hour period. 5.2 Cnidarians Cnidarians are a large and diverse group consisting of sessile and motile invertebrates, united by the fact that all members of the group are armed with stinging cells called nematocysts. The class of cnidarians we are most concerned with are the anthozoans, which includes all species of coral.

Hard corals are covered in greater detail elsewhere in this guide but we will be paying attention to soft corals, sea anemones and hydroids. Soft corals Soft corals unsurprisingly take their name from their lack of a skeletal structure. Most are filter feeders, and only a few species also host symbiotic zooxanthellae; the relationship between host and tenant in these instances is not as beneficial as it is to hard corals. Some close relatives of the soft corals, such as the gorgonians, do possess some skeletal structure but these sea fans and sea whips are nowhere near as rigid as the reef building species, using a more pliable endoskeleton to remain erect whilst facing the prevailing current and filter feeding from the passing water. Sea anemones Close relatives of hard corals, sea anemones take the form of distinctive and often large solitary polyps that are notable for the wide variety of animal symbionts that take advantage of the protection afforded by their stinging tentacles. Whilst anemonefish are the best known type of tenant (thanks Pixar!), shrimps, crabs and some species of pipefish also reside in large anemones. Close relatives of the anemones, the corallimorphs, possess a starkly different feeding strategy; they are known to engulf small fish like a Venus Fly Trap, rather than act as a shelter! Hydroids This is a diverse group of colonial organisms with forms ranging from small, feather‐like, branched colonies to large calcareous colonies such as those of the family Milleporidae or ‘fire corals’. All hydroids are capable of providing a painful sting to unwary divers, with one particular type of floating colony being world renowned: the "Portuguese man‐o'war". Often confused with jellyfish,

they are actually highly specialised colonial hydroids, with individual polyps responsible for a single purpose such as feeding or reproduction. 5.3 Molluscs The molluscs are a gloriously diverse group of over 160,000 species, of which about half are marine. Gastropods, bivalves and cephalopods are the three major marine classes and all are well represented in tropical waters. Gastropods Comprising 80% of all living molluscs, gastropods are the most successful and most commonly seen class of the phylum. They have a single shell, within which the body is protected from predators. All gastropods feed using their feet, rasping food from rocky surfaces, and range in size from numerous species no larger than a grain of sand to the queen triton trumpet, large enough to be one of the few predators of the notorious Crown‐of‐thorns starfish.

Not all gastropods have visible shells; some, such as sea slugs and nudibranchs instead rely on a combination of bright colours to signify their likely lethal toxicity to potential predators. Bivalves Bivalves have a pair of hinged shells, opened and closed by large abductor muscles, a mechanism that doubles as a mode of propulsion in some free living species. Bivalves include clams, oysters, mussels and scallops, of which the giant clams can reach up to 250kg and 100 years old. Many species burrow in soft sediment, but conspicuous reef dwellers such as the giant clam are mostly found wedged and cemented into reef crevices. Cephalopods With large, complex eyes and a nervous system considered to be the most advanced in the invertebrate kingdom, cephalopods are known as some of the most intelligent of all marine life, and are certainly among the most charismatic. Despite being molluscs, shells within most cephalopods are best described as vestigial with two notable exceptions; evolution has led to cuttlefish shells being adapted to serve as an internal buoyancy control device, and the elusive nautilus retains a striking, chambered shell used for camouflage and propulsion.

Cephalopods are rarely noticed on dives due to their excellent camouflage, created by colour changing cells called chromatophores which are also used in communication. Often the only indication that you are passing close to an octopus or squid is a plume of ink as the animal darts off, though some spcecies tend to be less skittish and may face and observe divers, only retreating if approached quickly. 5.4 Echinoderms The name echinoderm literally means ‘spiny‐skinned’ and refers to the tough, calcareous exoskeleton that characterises this phylum. Whilst echinoderms are chiefly known for their ability to regenerate lost body parts, they are also notable for using an internal structure akin to a hydraulic system for everything from locomotion to feeding on prey. Sea stars Usually sea stars have five arms radiating from a central disc‐shaped body, but in some species the number can be over twenty and in others the arms are not distinct, with the animal appearing almost circular. The most notorious member of this class is Acanthaster planci, the Crown‐of‐thorns starfish, which, when present in large numbers, will feed on and decimate a coral reef.

Sea cucumbers Sea cucumbers are elongate animals with a mouth surrounded by short tentacles at the front end of the body. Normally seen lying on the sandy bottom where they ingest large amounts of sand and digest any organic material, sea cucumbers often leave a trail of sand as they feed. Despite this, they are considered a delicacy in a number of regions. 5.5 Tunicates Tunicates are the invertebrates most closely related to humans, possessing a notochord (which develops into a backbone in the vertebrates) in their free‐living larval stage. When the larvae lands upon a suitable substrate, the tunicate irreversibly attaches itself to the surface, widens its mouth and absorbs the notochord. This is known as retrogressive metamorphosis, and is a rare transition in which the resulting adult form is less advanced than the larvae.

6 INTRODUCTION TO FISH

Fish as we know them are divided into cartilaginous fish (sharks and rays) and bony fish (everything else). The main bulk of fish that you will see and learn about in Timor‐Leste will be Osteichthyes, bony fish, although we hope you will get to see your fair share of sharks and rays as well. “Fish” is actually a tricky term to define, and as a group there is so much variation in form and function that a true scientific classification is surprisingly difficult; if you’re not being too pedantic though, a fish can be classed as something that lives underwater, breathes through a gill mechanism and has various types of fins and scales. Worldwide there are more than 20,000 known fish species, and coral reefs are home to more than their fair share with about 25% of these. In the Coral Triangle the number currently stands at 2,228, but new species are being classified or discovered all the time, particularly as diving techniques become safer at greater depths and submarine technology grows more sophisticated.

Fish species are grouped into families and subfamilies, though taxonomy can get complicated. Though over 75 reef fish families exist, we tend to look at no more than 25 when surveying in a single habitat, as well as their associated sub‐families. An ecosystem is a finely balanced food web, with huge numbers of interactions relating to predation or its lack.

Typically there are certain families whose presence in significant numbers is indicative of the health of a reef, or seagrass meadow and the addition or removal of certain groups can be damaging to the whole ecosystem. Lionfish, exciting and exotic sightings in the Indo‐Pacific, are an invasive species in the Caribbean; the presence of large bodied carnivores such as groupers and sharks often indicates a healthy ecosystem, and large numbers of butterflyfish, which are corallivores, can point to healthy amounts of hard coral on a reef; abundant damselfish can indicate too much algal growth on the reef surface, particularly in areas where herbivorous grazers such as surgeonfish and parrotfish are heavily fished, and that is barely scratching the surface. Putting these observations together with data collected over a long term we can measure the health of a reef system and assist local stakeholders in reacting accordingly.

Behaviour on a reef is a whole study of its own, and can be fascinating to the casual observer with just a little background knowledge; many recreational divers, upon learning a little, remark on how much it has enriched their underwater experiences. From mimicry to symbiosis, nuclear hunting to cleaning stations, beneath the veneer of beauty a wealth of drama ensues.

6.1 Introduction to common fish families This guide is designed as a brief overview, and you are by no means expected to know everything about reef fish by the time you arrive! We look at a number of characteristics when identifying fish: size, colour, accompanied by, location, eating, swimming (SCALES), and the more of these factors you can note down the better. When we state a preferred food for a family, remember that all fish are opportunistic feeders, and even herbivores are known to temporarily switch to carnivory if the opportunity arises! Another key point is that all fish can, to some degree, change their colouration,

from the appearance of blotches when hiding in seagrass to complete colour changes when courting. Each change depends very much on the fish and on circumstances.

We will be studying more than just these families, as well as some species which comprise a family all by themselves, but an introduction has to start somewhere… (All drawings from Reef Fish Identification, Tropical Pacific; Gerald Allen, Roger Steene, Paul Humann and Ned Deloach.)

Angels ‐ Pomacanthidae Among the most classic reef fish and the ones that many people think of when envisioning a coral reef. Angels are colourful, with ventrally compressed bodies and distinctive fins. They are clearly identifiable to family level, and although the juvenile of a species often has a very different appearance from the adult, there is no sexual dimorphism in adults. There are two forms in the family; one is large, robust, has flamboyant fins and can be quite unafraid of divers; the other is smaller and more cryptic, and can be confused with damselfish. Most species primarily eat sponges, for which they have very little competition due to the low nutrient count and stony texture. Angelfish are protogynous hermaphrodites, capable of changing from female to male if the need arises.

Butterflies ‐ Chaetodontidae These small reef fish are monogamous, with pairs mating for the duration of their lives, which can be an identifying characteristic in itself. Round, laterally compressed bodies with protruding snouts for eating coral (their main food source) make them nice and easy to pick out, and there are no differences between adult and juvenile stages of life or between sexes. Until fairly recently they were classed as one family with the angelfish, until enough taxonomical differences were confirmed. The largest species grows to 30cm, and is considered a bit of an outlier. Cardinalfish ‐ Apogonidae Cardinals are among the lesser spotted reef fish as they are neither large nor flamboyant, usually between 5cm and 15cm. Preferring dark crevices and overhangs to open reef by day, they have large eyes to aid nocturnal vision, and are usually some shade of dark red or orange. Identifying characteristics tend to be located on the eye or the tail. Damsels ‐ Pomacentridae Damselfish are one of the most numerous families on any reef worldwide, and have been categorized into several sub‐families to deal with the huge number of adaptations they have evolved. As a family they all tend to be small (under 15cm) and most are territorial. Juveniles can differ in colouration from adults, depending on the species. Anemonefish – for those of you who haven’t seen Finding Nemo, an anemonefish is classed as any damselfish that lives in symbiosis with any species of anemone. The fish has a protective coating of

mucous to prevent it being stung by the anemone’s tentacles, but predators wary of such stings tend to leave the small fish alone. Chromis – these members of the damsel family are more likely to be found in the crowd of plankton feeders above the reef than hiding in it, in loose aggregations that can number into the thousands in the right area. Tails that are more forked than their cousins’ give them a slightly more streamlined look. Damsels – these are classic reef dwellers who make their homes in holes with associated small patches of algae which they farm for food, eating both the algae and the various small crustaceans that come with it. The males defend their eggs with ferocity and will even nip a diver whose hand gets too close. Dascyllus – the shyest of the bunch, dascyllus hover mere centimetres above their chosen coral head, diving into the branches for cover when threatened. Sergeants – bulkier than the other family members and striped vertically, sergeants spend most of their time patrolling in the same area of water as the chromis, but when nesting they become very defensive of their nests and stick very close to their territory on the reef substrate. Emperors ‐ Lethrinidae Well known as excellent food fish, emperors are less colourful than traditional reef fish and have a tendency to make their skin take on a mottled colouration when at a standstill, before returning to their usual silvery hues when moving. With slanted heads and flat‐bottomed bodies, these fish tend to be found off the sides of the reef, eating crustaceans and whatever else they can find on the sand. They can grow up to 1m, but are likely to be 30‐50cm. Fusiliers ‐ Caesionidae Above the reef and off to the side in the blue water we find our slender, schooling fusiliers. Schooling fish avoid collisions using the feel of water movement over their lateral line, and in fusiliers this line is often marked in some way. With its slim, fusiform body, between 15 and 35cm, and forked tail with a very narrow base, fusiliers are reef fish adapted for a pelagic, open water lifestyle. Goatfish ‐ Mullidae Taking their name from their terrestrial counterparts, goatfish have two chemosensory appendages, known as barbels, for tracking down food under loose sand; if you see a small cloud of sand being created, chances are there’s a goatfish at its centre. When not in use a goatfish’s barbels are tucked up under its chin, but these fish are still identifiable through their shape and behaviour; a very flat underside is required when bottom‐feeding, and a nicely forked tail gives a clear ID; goatfish tend to be around 30‐40cm.

Groupers ‐ Serranidae Many people often assume that a grouper must be enormous, and forget the numerous small species among the aptly named Goliath Grouper which can reach 300cm. Many of the species we monitor are small, 30‐70cm, but large bodied compared to their other reef denizens. No matter what their size, they are expert ambush predators, with enormous mouths used to engulf prey whole and wide, flared fins to hold them in position until they are ready to pounce, and powerful tails for short bursts of speed when required. This is another family of fish which practises hermaphroditism, both sequential and protogynous, and removal of too many in one size bracket may leave an imbalance of one sex or the other. Groupers are often found at cleaning stations, as the folds of skin around their mouths and gills are often colonised by a range of parasitic organisms.

Anthias (Anthiinae) – scattered above the reef close to open water in loose, colourful aggregations are the anthias, confusing to identify as the tend to mix their schools, but spectacular to look at, and barely seeming related to the heavy groupers at all at a maximum size of 20cm. Males and females tend to have different colourations and this can make them tricky to identify to species level as there are lots of similarities between species. Luckily they’re not that spooked by divers, so you can take a good long look at them. Jacks and Trevallies – Carangidae Instantly recognisable with their silvery skin and powerful forked tails, these are the real ocean‐going pelagic swimmers, and make excellent food fish due to their almost constant muscle use and large size, up to 120cm. Coming in to the reef to feed on fish and crustaceans, jacks are sometimes solitary but usually aggregate in loose schools, and the differences between them and the reef fish in shape and colour makes identifying them very easy.

Parrotfish – Scaridae Descended from wrasses, parrotfish are one of the more specialised groups of fish on a reef. Their teeth, fused into powerful beaks, are modified for scraping algae off rocks and coral, often taking in a large amount of inorganic content at the same time; much of the sand on glorious white beaches around the world has actually passed through a parrotfish in this process. Parrotfish swim primarily with their pectoral fins, flapping over the reef with the occasional peck at some algae (an image which further solidifies the bird comparison), and their

thick bodies and large, clearly defined scales make identification easy to family level. Their familial structure is key to identification further, with three life phases in each species showing three distinct appearances, and colour changing with sex; size can also be a key factor with large amounts of variation across the species, from 18‐150cm!

Snapper – Lutjanidae The importance of snapper as a food fish cannot be overstated, and neither can its importance on a reef. Like emperors, they operate at the edges of reefs, primarily eating fish but supplementing their diet with any invertebrates they can hunt along the way. Most hunt nocturnally, but they are good all‐rounders, with balanced bodies, negligible colouration and large mouth with protruding canines. Some species can grow quite large, up to 1m, with most growing to 40‐50cm.

Soldierfish and Squirrelfish – Holocentridae Like cardinalfish, soldiers and squirrels are nocturnal, and can generally be found in holes and crevices on reefs, or under overhangs. They both have large eyes and reddish colouration, with clearly defined scales and spiny dorsal fins, but differ from each other in the shape of their face; soldierfish have blunt, rounded snouts while squirrelfish faces are much more pointed. Squirrels also have a spine in front of their gill‐cover which can be venomous. They tend to be small to medium sized, rarely exceeding 30cm. Surgeonfish – Acanthuridae Surgeonfish, common in mixed groups on reefs, are named for the bony blade that protrudes from the tail base, the scalpel, which can either be a tiny nub or a well‐developed blade; in the subfamily unicornfish each member has a pair of blades on each side. These are often marked out and are one of the key identification traits for this family. Surgeons and unicorns both swim primarily with their pectoral fins, as do parrotfish and wrasses, and can be found cruising above the reef or feeding among the corals. They are typically small fish, around 30cm, but can reach 60cm. Surgeons – for another Finding Nemo reference, look no further than Dory the ditzy palette surgeon. Accurately represented in the film with a classic oval body that is ventrally compressed and swimming with the pectoral fins, these fish are grazers that often move over the reef in large aggregations which swarm down on algal growth; small protruding mouths with a pouty look are the perfect adaptation for this feeding style.

Unicorns – as mentioned previously these fish have a pair of scalpels either side of their tail base rather than just one, and they are generally less flamboyantly coloured than their cousins. The oval body shape is there, but slightly elongated as if stretched from the tail, and some species show the key trait of the mythical unicorn, a protruding horn above their mouth; in some species it is no more than a bump, in others a full narwhal‐like horn. Triggerfish – Balistidae Triggerfish are among the most charismatic reef dwellers, with flamboyant colours and an instantly recognisable swimming method. Their bodies are diamond‐shaped and they have a primary dorsal fin which, when locked into its distinctive trigger shape in a threat display, gives the family its name, and they swim with their secondary dorsal fine and their anal fin in a sideways oscillation. Species rang e from very small to quite large, with the Titan Trigger reaching 75cm, and can be fiercely protective when nesting; if challenged they may bite, so swim clear of the cone‐shaped area of water they may be defending.

Filefish – closely related to triggers in body shape and swimming mechanism, filefish are more cryptic and far less showy. Their bodies are more compressed than their cousins, and they are far more likely to hide in a hole than bite; they also have a long trigger fin, but it is flipped up when threatened, rather than locked in place.

Wrasses – Labridae Wrasses are one of the most numerous and varied families of fish you will encounter on a reef, with adult sizes that range from 6cm‐ 230cm; in the Indo‐Pacific they are outnumbered only by gobies in sheer species numbers. All share certain characteristics though, such as swimming with their pectoral fins as parrotfish and surgeonfish do. Wrasses tend to be among the more opportunistic feeders on a reef, first to appear when another fish has found a meal, among the dust clouds kicked up by goatfish, and developing symbiotic relationships whereby their role as a cleaner protects them from predation. Large canines make light work of most crustaceans or small invertebrates, and wrasses of any size can be seen using their teeth to great effect. In a life cycle similar to their close relatives, the parrotfish, each species has noticeably different appearances during each of its three life phases.

7 KEY MARINE GROUPS

7.1 Turtles The Coral Triangle is home to six of the world’s seven extant species of marine turtles. Turtles are reptiles that have evolved for life underwater, with a more streamlined carapace than their terrestrial cousins, and fins rather than legs. They are capable of remaining underwater for up to forty minutes, and are mostly omnivorous, though most show a preference for some things over others; hawksbills tend towards sponges, leatherbacks eat mainly jellyfish, and green turtle adults tend to favour seagrass as their sole source of food. This is particularly important, because few animals subsist solely on seagrass, and their constant grazing keeps the seagrass meadows healthy in the same way that a lawn needs cutting regularly; it leads to healthier grass that spreads across a wider area, which is essential as global seagrass depletion rates are approaching 7% per year.

Despite conservation and awareness raising over decades, all marine turtle species are still at risk; hawksbill and Kemp’s ridley turtles are listed by the IUCN as Critically Endangered, the green turtle as Endangered and the loggerhead, Olive’s ridley and leatherback turtles are all Vulnerable (the flatback turtle, not found in Timor‐Leste, is listed as “data deficient”). In some areas of the world conservation efforts and changed laws are having an effect, with success in the Caribbean in terms of increased nesting sites and larger numbers of hatchlings, but no improvement in the Philippines where there is still demand for turtle eggs, and laws making the catching of turtles and taking of eggs illegal have had little effect.

Little is known about turtle habits in Timor‐Leste, but various NGOs are working towards gathering data and implementing conservation actions; no‐take zones are critical to allow fish and turtles space to breed undisturbed, and large campaigns are running against the disturbing of turtle nests. 7.2 Marine mammals

Cetaceans The Wetar and Ombai Straits are migratory channels for many species of whale and dolphin, and the area has been described as a cetacean hotspot. Short‐finned pilot, melon‐headed, humpback, blue, beaked and sperm whales are all regular visitors, as well as spotted, spinner, bottle‐nosed, striped, Risso’s, Fraser’s and rough‐toothed dolphins – quite a list for a small country with huge ecotourism potential. These waters reach depths of 3,000m, providing more than enough space, and food, for such vast numbers of mammals. Blue whales are listed as Endangered and sperm whales as

Vulnerable, and to see either with regularity is exciting; to know that these are migratory channels is particularly valuable for monitoring efforts.

Dugongs These charismatic marine mammals are the last extant members of the family Dugongidae, related to the three manatee species, all four members of the order Sirenia, but not crossing ranges with them anywhere worldwide. Their smooth bodies and fluked tails can be confused with dolphins at first sight, but they lack a dorsal fin and have a highly mobile face, with an upper lip that has adapted for foraging for seagrass.

With a limited range and a long life‐cycle they are at risk from boat collisions, hunting and habitat loss, dugongs being another species in addition to the green turtle which lives only on seagrass. Known populations are fragmented, and in several places they are at risk of becoming locally extinct; they are listed as Vulnerable by IUCN, but population estimates are inexact due to their elusive nature and the turbidity and remoteness of their chosen habitat.

Blue Ventures’ work in Timor‐Leste includes designing a replicable model for ecotourism through marine conservation which incentivises dugong and seagrass conservation for the local population. Through education and awareness raising, the presence of dugongs will be highlighted as valuable natural resource and source of civic pride for coastal communities throughout Timor‐Leste.