Assessment of Seagrass Beds and Reef Area in front of the Nikko Hotel
Seagrass beds, sand flats, and rocky areas characterize the coastal area located directly in front of the Nikko Hotel. Supporting a high diversity of coral, fish and invertebrate species, this part of the coastline is one of the few areas on the East coast of Nusa Dua where a break in the barrier reef has resulted in a channel being formed. To the South of the channel the reef area (mainly algal covered rock) continues to the shoreline.
The beach in front of the channel slopes quickly to a depth of between 3 and 5 meters. Here the bottom is covered in several seagrass species before giving way to large areas of sand interspersed with initially seagrass and then coral covered rock formations.
Seagrass ecosystems have very high primary productivity allowing them to provide nutrients and support a number of marine organisms. Their main role as a nutrient source occurs upon decomposition when they release these nutrients into the water. Important fish species rely on the seagrasses, as do shrimps, sea cucumbers, urchins, crabs and many other species.
The reef area behind the seagrass beds is composed of large rocky outcrops divided by channels and a sandy bottom. The rocks are adorned in a variety of corals and sponges. The coral species abundant in the area are typical of those found in areas of high wave action with the majority encrusting hexacorals.
A high diversity of fish and invertebrates were identified on each snorkel in the area. The Lined Surgeonfish (Acanthurus lineatus) an algal grazer, was the dominant species observed. Several other reef fish including angelfish and parrotfish were also seen. Eight different species of butterflyfish were recorded in a one-hour period. Butterflyfish are excellent bio-indicators favouring healthy reef systems with high species diversity. That said there is a noticeable lack of commercially valuable species such as snapper and grouper, probably as a result of over fishing. However, if managed appropriately the sanctuary would provide a protected area for the population to recover supporting a high density and diversity of fish species.
In addition to the aforementioned species, the area appears to support a population of Blue-spotted Stingray (Taeniura lymma). Together with sharks, stingrays are apex reef predators and an integral part of the reef ecosystem. Once common throughout SE Asia their numbers have declined drastically in recent years.
The reef flats adjacent to the channel are home to a number of fish and invertebrate species. Moray eels, octopi and banded coral shrimp were all identified. Though present this is a popular area with the local community for gleaning and population numbers are lower than would be expected. At low tide many people can be see scanning the reef flats gathering everything they can find from amongst the rock-pools. Unfortunately, many of the organisms taken in this area are juveniles (picture, right) hiding in the shallows from the predators in deeper water. Furthermore, intensive collecting of certain species may lead to severe alterations in the balance of the ecosystem. Diadema urchins (long-spined sea urchins) are a prime example of this. These animals inhabit crevices and areas between rocks in the shallows where they feed on algae. If too many of these grazers are collected it may cause an algal bloom, whereby corals are outcompeted, reducing biodiversity in the area.
Trash is a major problem in Bali and this is particularly evident on the reef in the area. Plastic bags litter the sea floor smothering corals and killing marine life. Much of the garbage travels down the coast with the currents ending up on the reef where it remains snagged on rocks and corals. A regular snorkel clean up to physically remove bags and other forms of rubbish from the reef would assist in protecting wildlife and contribute towards making the area more attractive for recreational activities.
What is a Marine Protected Area?
A Marine Protected Area or Marine Reserve is a coastal or offshore area of a marine region that has been set aside for management and conservation measures. Including a no-take zone where fishing activities are prohibited. Given time, reserves allow different species the chance to freely reproduce and help to increase biotic and genetic diversity. Through the restriction of fish harvest, species are given an opportunity to grow larger and reproduce more easily. This in turn results in a faster turn over of fish from inside the sanctuary to outside (spill-over effect) increasing yields for fishermen. Many species of fish including Grouper and Snapper reach maturity at around 5 years old, producing exponentially more offspring in the process. If juveniles are fished before reaching maturity the population becomes depleted and may lead to local extinction. Example: a 12kg Snapper (at approx 5 years old) can produce as many as 200 juveniles, while a 1kg Snapper will only produce a handful. Selective targeting of certain species may also alter the ecosystem.
Conflict of Use
The area identified for the creation of a MPA in front of the Nikko, is currently used by hotel guests for swimming, and the local community for fishing and gleaning (the collection of marine organisms from low tide areas). ROLE Foundation proposes creating a MPA consisting of a no-take zone (to include no gleaning) which would allow fish numbers to increase and provide a safe area for guests to swim and snorkel away from the fishermen’s hook and lines. Given time this will serve to increase fish stocks outside of the MPA while simultaneously protecting the biodiversity of the area.
The exact location and size of the MPA would require discussion between all of the relevant stakeholders through an integrated approach to Coastal Resource Management. This would need to include the Bali Hotel’s Association, local government agencies and community groups.
Planning and Implementing a MPA.
1. Habitat analysis and identification of issues.
2. Planning and preparation.
3. Implementation and creation of action plan.
4. Evaluation and monitoring.
The coastal area in front of the Nikko Hotel exhibits a high biodiversity of marine organisms but is under extreme pressure in terms of over fishing, gleaning, build up of trash and excess nutrients in the water. Through the implementation of a MPA and given proper management there is an opportunity to safeguard the biodiversity of the area, while simultaneously increasing fish stocks outside the sanctuary for fishermen. Furthermore, a clean healthy beach and reef environment will be attractive to tourists and can be utilized to promote additional leisure and educational services opening up the possibility of further choices to the consumer. Recently a shift in purchasing towards organic, ethical and green products has indicated an increased environmental awareness regarding consumer choice. By displaying ethical and environmental credentials a business is able to expand its appeal to new customers without alienating its existing clientele.
(Marine Biologist Role Foundation)