Belize - Manajemen Perikanan | Ketahanan Karang

Protecting Reef Grazers to Enable Coral Reef Recovery in Belize

Lokasi

Belize Barrier Reef System, Belize

Tantangan

Lokasi Sistem Belize Barrier Reef.

Belize terkenal dengan keanekaragaman hayati yang luar biasa, baik darat maupun laut. Terumbu karangnya telah lama dianggap beberapa terumbu paling unik dan unik di Karibia, namun mereka mulai menunjukkan tanda-tanda kerusakan yang mengkhawatirkan pada pergantian abad ini. Sebuah survei 2006 tentang terumbu 140 di seluruh Belize menemukan bahwa tutupan karang hidup telah menurun dari sekitar 30% di 1995 ke rata-rata 11%. Wildlife Conservation Society (WCS), yang telah bekerja di Belize sejak 1980s untuk membantu melestarikan lingkungan laut negara itu, melakukan penelitian tentang kesehatan perikanan Belize dari Stasiun Cadangan Kelautan mereka di Glover's Reef.

Glover's Reef terletak di dalam Belize Barrier Reef Reserve System, tempat memancing, dan juga spearfishing, diperbolehkan. WCS menemukan bahwa ikan kerapu dan beberapa kakap sekarang terlalu banyak ditangkap dan proporsi ikan kakatua dalam tangkapan berlipat dua antara 2004 dan 2008 karena ikan kakaktua dianggap oleh nelayan sebagai “ikan terbaik berikutnya” untuk dipanen.

Fakta bahwa para nelayan menyasar spesies yang merumput di terumbu adalah masalah serius dengan efek jangka panjang bagi kesehatan terumbu Belize. Pemakan terumbu seperti ikan kakatua memainkan peran ekologis yang penting dalam terumbu karang; dengan memakan ganggang dalam jumlah besar, mereka menjaga pertumbuhannya, memastikan bahwa ia tidak tumbuh terlalu besar di terumbu. Alga dapat menekan karang, menghambat pertumbuhannya, dan mengurangi keberhasilan rekrutmennya.

Rainbow parrotfish (Scarus guacamaia), ikan herbivora terbesar di Karibia. Foto © Julio Maaz / WCS

The health of reefs is therefore closely linked to the presence of herbivorous fish such as parrotfish. As fishermen in Belize continued to harvest parrotfish, their numbers started to rapidly decline. Research on the change in fish communities after a seven-year period (2002-2009) of fishing in Belize showed a 41% decline in parrotfish over that time period. Overfishing parrotfish already has had observable effects on Belize’s reefs. One study found that an atoll reef lagoon at Glover’s Reef that had once been very healthy with 75% coral cover now has less than 20% coral cover because of algae over-growth.

Tindakan diambil

The traditional management option to help overfished species recover has typically been fishing closures. However, WCS conducted a 14-year study at Glover’s Reef and found that while a fishing ban in the Conservation Zone of the marine reserve was effective in helping predatory species such as barracudas and snappers recover, it had little effect on the recovery of herbivorous species. This meant that a fishing ban would not be enough to reduce the growth of algae and help corals recover. This information, along with recent information on the poor health of Belize’s reefs, helped stakeholders understand the need for an alternative and more innovative way to protect Belize’s reefs: protect major reef grazers. It was local fishermen who first voluntarily recommended a ban on fishing parrotfish after it was made clear to them how important these fish were to the health of the reef and therefore to their livelihoods. In April 2009, the voluntary ban on the fishing of parrotfish became national law when the government of Belize passed the 2009 Fisheries Regulations 2009 to protect overfished species. The 2020 Fisheries Resources Act added new regulations to those established in 2009.

An example of one type of fishing boat used in Belize. Photo © Julio Maaz/WCS

The 2009 regulations prohibited any taking of parrotfish and surgeonfish in Belize’s waters. Both species are major reef-grazers, so the law directly addressed increases in catch of herbivorous fish and the negative impact this was having on reef health. By giving parrotfish and surgeonfish full protection, the hope was to help their numbers recover and to in turn reduce the growth of macroalgae threatening Belize’s reefs. Belize was the first country to pass a national law to protect reef grazers, which are critical to the health of coral reefs. In fact, many considered this law a new standard for coral reef protection, as management strategies up until then had mainly focused on marine protected areas (MPAs). Of course, enforcement and compliance is key to ensuring the success of this national-level ban, as is the prevention of legal access to international export markets for these products. WCS provided technical aid to the Belize Fisheries Department to ensure that fisheries officers and patrols enforced the law.

Peter Mumby menjelaskan pentingnya ikan kakatua sebagai penggembala yang menjaga kesehatan terumbu karang bagi sekelompok besar nelayan di Belize City. Foto © WCS

A second set of regulations helped protect the endangered Nassau Grouper (Epinephelus striatus), listed as Endangered by the IUCN Red List of Threatened Species. Fishing of the Nassau Grouper became heavily regulated – with minimum and maximum size limits, and all groupers must be brought in whole so that catch rates can be monitored. Additionally, spawning aggregations of Nassau grouper are protected, and spearfishing is banned within marine reserves. A third set of regulations creates a number of “no-take” zones in protected areas, which are closed to fishing. The areas selected are biodiversity hotspots with unique and/or fragile ecosystems and/or species.

As of 2022, the focus on reef conservation is shifting towards digital enforcement innovations and improvement of access to higher value markets for Belize’s legal fisheries (lobster and conch on the international market, other finfish species on the domestic market). The Ministry of Blue Economy and Civil Aviation is promoting the improved ecological and socioeconomic sustainability of all marine economic activities. Focusing on individual species as a conservation approach, while valuable, will likely begin to be expressed more in the wider context of additional objectives of the Ministry for marine economic activities at a holistic level.

Seberapa sukseskah itu?

There is some strong evidence that the fishing ban is helping reef-grazers recover. In 2011, the herbivore biomass in Belize surpassed levels recorded in 2006 and increased 33% above the low levels measured in 2009. This increase in herbivore biomass should in time translate to a decrease in algae dominance in Belize’s reefs.

Efektivitas larangan penangkapan ikan dalam memulihkan populasi ikan dan kumpulan karang di Belize dievaluasi dalam penelitian antara 2009 dan 2011. Peningkatan biomassa ikan herbivora ditemukan di sekitar setengah dari lokasi yang diteliti, tetapi tutupan karang dan makroalga tetap sama. Namun, para penulis penelitian mengaitkan kurangnya perubahan pada tutupan karang dan ganggang dengan seberapa baru pelarangan pemakan ikan oleh para terumbu karang.

Stoplight parrotfish (Sparisoma viride) dengan tangs biru, yang juga dilindungi oleh pemakan rumput. Foto © Virginia Burns / WCS

Upaya penegakan hukum tampaknya berhasil karena hanya ada sedikit kasus penangkapan ikan kakatua secara ilegal sejak larangan tersebut diberlakukan. Hasil studi genetik sampel fillet tahun 2012 di seluruh Belize juga menunjukkan kepatuhan yang sangat baik terhadap larangan - lebih dari 90% fillet yang diperiksa bukanlah ikan kakatua.

Pelajaran yang dipetik dan rekomendasi

Fishermen are key stakeholders in marine conservation. Incorporating fishers’ tradition ecological knowledge of and perspectives on fisheries and reefs into conservation and management plans is critical to ensuring the success of the conservation plans and also to ensuring that the management plans serve both the needs of the communities, as well as the species or areas being targeted for conservation.
Extensive research on the subject at hand (in this case, the link between parrotfish density and reef health) is essential to making informed decisions. Additionally, finding ways to separate this from other potential causes of reef health decline such as seawater temperature, ocean acidification, arrival of lionfish in the Caribbean, hurricanes, pandemics leading to economic hardship for fishers, and other potential threats is extremely important.
Involve fishers directly in the design and implementation of research and monitoring so they are part of the processes that lead to research outputs and decision-making.
Reef recovery takes time – although data indicate an increase in biomass of parrotfishes, slow-growing corals need long-term protection to fully recover.

Ringkasan pendanaan

Program monitoring dan pendataan tangkapan ikan WCS telah dilakukan selama bertahun-tahun bekerja sama dengan Dinas Perikanan, dan akan terus dilakukan dalam upaya pencatatan pemulihan ikan kakatua di Glover's Reef dan melacak kesehatan terumbu karang. Pekerjaan ini didanai terutama oleh Oak Foundation, USAID, dan Summit Foundation.