FROM PLANKT IVORE S T O PRE DATORS

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1 21 January FROM PLANKT IVORE S T O PRE DATORS Insights into the Sustainability of Lakshadweep s Marine Resources A review of research work undertaken in the Lakshadweep Islands by the Dakshin Foundation Mahima Jaini, Research Assistant India s only coral reef atolls, the Lakshadweep islands, boast of crystal clear waters, tranquil island living and diverse marine life. These ecologically sensitive geological wonders host over 70,000 humans in a meagre land mass that combined amounts to 32 Km 2. Lakshadweep islanders are closely connected to the land and sea, most making a living off coconut cultivation or fish harvest. Tuna constitutes over 80% of the total marine harvest. Majority of the tuna caught in Lakshadweep water is harvested by the pole and line fishing technique, a small-scale commercial method that has low habitat impact and high species selectivity. The Lakshadweep live-bait pole and line tuna fishery utilises small planktivorous fish from island lagoons and reefs as bait to harvest oceanic skipjack tuna (Katsuwonus pelamis); thus targeting the lower trophic levels in the reef ecosystem and higher trophic levels in the open ocean system, avoiding the sensitive slow growing, late maturing top predators of the reef. However, recent changes in tuna stock abundance and associated fishing practices threatens the sustainability of this fishery. Our project was proposed in response to community concerns regarding declines in live bait resources in the tuna fishery. Our baseline work in the fishing season revealed significant concerns regarding the tuna resource. This season we are continuing our baitfish ecological research, while expanding our social surveys to understand the dynamics of the tuna fishery. Being keen and knowledgeable stewards of their resource, fishermen have expressed an interest in a community-based catch monitoring programme and we hope to initiate one in the coming weeks. Our work thus far has been restricted to the islands of Agatti, Kadmat, Kavaratti and Minicoy but we hope to expand this in the coming months in order to paint a more realistic picture regarding Lakshadweep s marine resource utilisation. Project Title: Community-based monitoring of baitfish populations along a gradient of fishing pressure in the Lakshadweep islands Objectives: 1. Assess baitfish populations along a gradient of fishing pressure and environmental parameters to determine the role of anthropogenic factors in regulating planktivore abundance. 2. Evaluate fisher perspectives regarding the state of the tuna fishery; historical trends, current status and future directions. 3. Establish a community-based fishery monitoring program that covers aspects pertinent to the involved fisherfolk.

2 21 January Pole and Line Tuna Fishing 10% of the Indian Ocean tuna catch comes from small-scale pole and line fisheries operating out of the Maldives and Lakshadweep islands, that use small planktivores from island lagoons and reefs as live-bait to target oceanic skipjack tuna (Katsuwonus pelamis). Pole and line fisheries are considered sustainable as they target the relatively resilient skipjack tuna using highly selective gear that has minimal impact on the habitat. Skipjack tuna are characterised by large stock size, fast growth, early maturation, prolific yearround spawning over wide areas, relatively short life spans and highly variable recruitment. They reach sexual maturity by 1.5 years of age i.e. at approximately 45 cm length and 1.7 kg in weight. In addition to skipjack, the pole and line fleet might also catch yellowfin (Thunnus albacares), bigeye (Thunnus obesus), kawakawa (Euthynnus affinis) and Auxis spp., but these species are rare in homogenous open ocean skipjack schools. The pole and line technique is said to have spread to the Lakshadweep island of Minicoy from the Maldives some 200 years ago. The Lakshadweep Department of Fisheries helped introduced this traditional fishing method to the rest of the islands in the late The main product of the fishery is smoked and dried form called Mas, a commodity that is exported to Sri Lanka and other south east asian countries. Above: The stern of a Lakshadweep pole and line fishing boat Right: Yellowfin & dogtooth tuna Emerging Changes & Challenges Recent declines in tuna landings and the limited access to profitable markets possesses significant threats to fisher livelihoods. Even though pole and line caught tuna is world recognised as sustainable, the end consumers of mas, based in south east asian countries, China and Japan, are unfortunately not interested in best practice seafoods. In order to fetch better prices for Lakshadweep pole and line skipjack infrastructure that enables the export of frozen and canned tuna to European markets is required. On the other hand, increasing use of Fish Aggregating Devices (FADs), and rising local and international fishing pressure may be leading to unprecedented declines in skipjack populations, but lack of accurate data makes this assessment challenging. FADs contribute to growth overfishing as they tend to attract smaller skipjack. Catch from FADs most often comprises of undersized skipjack along with high levels of bycatch of juvenile yellowfin, rainbow runners and mahi mahi. Despite recognising this as a detrimental practice, fisherfolk and fisheries department alike promote this strategy as it provides fishers a guaranteed catch and security in this era of rising fuel prices and variable landings. Our proposed catch monitoring programme hopes to shed light on these developments and help fill existing data gaps.

3 21 January From glassy apogons and colorful pomacentrids to the sleek sprats, Lakshadweep s lagoons and reefs harbour large amounts of baitfish. Unfortunately, being under a strong influence of environmental drivers, the harvest of these planktivorous species if left un c h ec k ed c an h a v e dir e consequences for the communities that depend on them. In the past there has been a see-saw relationship between tuna catch and baitfish availability, highlighting the need for better monitoring and management. Lakshadweep Resources s Baitfish The tuna fishery opportunistically utilises a wide array of small planktivorous fish that are found in island lagoons and reefs. Fishers preferentially target clupeids Spratelloides delicatulus and S. gracilis but also use small planktivorous fusiliers (caesionids), anthias (serranids), cardinal fish (apogons) and damselfish (pomacentrids). These fish differ greatly in terms of their biology, life history, harvest methods, fishing location etc. but are tied by one simple truth that they all consume plankton and usually occur in large schools. Certain groups, like apogons and pomacentrids, are closely associated with coral and thus their harvest requires extra care so as not to damage the sensitive structure. In the 1960s when the pole and line technology was transferred to the rest of Lakshadweep from Minicoy, so were most of the baitfish harvest practices. But unfortunately this transfer failed to bring with it the management practises followed in Minicoy to safe guard their baitfish resources. In Minicoy, till date, fishing boats have designated coral boulders that act as boat specific safe houses for apogon baitfish. Minicoy also uses a wider array of baitfish including atherinids, engraulids and serrainds in addition to the regular list. Whereas the other islands most often only use the sprats. Lack of monitoring an d management of baitfish is of concern, especially at times when tuna is abundant. Over the last 20 to 30 years, a potentially harmful but under-reported fishing practice has arisen in these waters. Fishermen have learnt to target Spratelloides delicatulus at time of spawning, when the fish occur in large numbers and are relatively sedentary thus making for easy catch. The unchecked and unregulated harvest of spawning populations of one of the most important baitfish resources requires further investigation and research upon its impact. Our surveys are a step in this direction. L A KS H A DWEEP BA ITF IS H Baitfish Local Name (Minicoy / Rest of islands) Location Method Spratelloides delicatulus Hondeli / Hondeli Lagoon / Reef Encircling net Spratelloides gracilis Rahi / Rahi Reef Lift net Apogonidae Bodi / Bodi Lagoon / Reef Lift net Pomacentridae Nila mahi / Nila mahi & Pachha challa Lagoon Lift net Caesionidae Muguram / Muguram & Pachha challa Lagoon / Reef Lift net Atherinidae Phitham / Maad challa Lagoon Encircling net

4 21 January Social Surveys Fishermen interviews have revealed significant declines in tuna catch volume and size over the past decade, and this has been accompanied by the spatial expansion of fishing grounds. Factors most often cited for declines in tuna catch include changes in currents, especially since the 2004 tsunami, increase in external fishing pressure and tuna tagging. There was little to no concern regarding baitfish abundances. During interviews fishermen voiced their concerns regarding the fisheries department. In Kavaratti, the main complaints were associated with market access and diesel availability. Whereas, in Agatti, as our interviews were conducted prior to the instalment of the most recent FAD, most complaints were regarding the lack of nearby FADs but market access and diesel supply concerns were voiced as well. Fishermen also complained about a dearth of spare parts and experienced engineers to fix engine problems. Improvement in provided schemes and subsidies, increasing ice availability and information on reef fishing was also requested. Currently the main issue is regarding the export of mas and the lack of a decent price for it. Safeguarding tuna fisher livelihoods is important so as to avoid an exploitation of the more valuable but highly sensitive reef resources. Dakshin Foundations Biodiversity and Resource Monitoring Programme As conservationists in human use sea-scapes our challenge is to conserve biodiversity without compromising local livelihoods or the principles of environmental and social justice. World over recent efforts in this direction have led to the emergence of participatory and communitybased approaches to conservation. We view such public participation, especially by means of community-based monitoring as a strategy complementary to environmental education, and are currently in the process of initiating community-based fisheries monitoring projects in Lakshadweep, Andamans, Karnataka and Tamil Nadu. Community-based Catch Monitoring Community meeting with the Agatti fishermen s Union, October Fishermen were supportive of a community-based catch monitoring program and helped identify parameters of interest; including tuna catch volume and size, baitfish use, fuel usage, external fishing pressure and use of Fish Aggregating Devices (FADs). We have completed the design and print of these catch monitoring notebooks. The data sheets that were designed with the input of local Kavaratti and Agatti fishermen will help quantify catch and effort associated with the tuna as well as that for baitfish. They will also provide species and size specific catch information, along with data on weather, external fishing pressure and frequency of use of FADs. The data generated through this community-based programme is property of the fishermen alone. We plan to simply facilitate the collection and analysis of this information but will in no way be entitled to it. Use of this data will require the permission of the fisherfolk. The aim of this intervention is to increase stakeholder participation in decision making, in hopes of facilitating a shift from that of exploitation to sustainable utilisation. Data generated via the community-based catch monitoring work has the potential to inform resource users and managers about the changes in the fishery and ways in which to better manage them.

5 21 January Ecological Surveys Our reef surveys revealed highest densities of Spratelloides baitfish in the islands of Kavaratti and Agatti. Additionally, Kavaratti reefs had the highest densities of planktivorous caesionids, apogonids and serranids, indicating the role of factors other than fishing pressure. Average Baitfish Density (# per 60min Survey) Average Baitfish Density (# per 60min Survey) a. Reef clupeids Kadmat Kavaratti Agatti Minicoy b. Reef caesionids Kadmat Kavaratti Agatti Minicoy Average reef a. clupeid & b.caesionid abundance (±S.E.) sampled in February-March 2013 in Lakshadweep islands arranged in increasing order of fishing pressure. Lagoon surveys indicate a weak negative relationship with fishing pressure. And our current surveys to document seasonal variations in lagoon baitfish is a step towards teasing apart environmental forcing from anthropogenic. Spatial densities of baitfish sampled at reef (square) and lagoon sites (circle). Interestingly, we have consistently found higher baitfish densities on the Eastern reefs of all islands, thus indicating distribution and abundance of these organisms. Ongoing work Surveys of baitfish to document inter-island and seasonal variability Fisher interviews to understand the current status of the tuna fishery Community-based catch monitoring Future plans In the next few months, as we wrap up our surveys, we will have generated a large amount of data on baitfish in the islands of Agatti, Kadmat, Kavaratti and Minicoy. Of primary interest is the impact of fishing on planktivore populations and we plan to conducted detailed statistical analyses to tease apart responsible factors. In addition to our ecological research, our social research is also generating a lot of information regarding ongoing changes in the tuna fishery. With the advent of the catch monitoring programme we hope to better engage the community in natural resource research and management. The future direction of the livelihood related research is yet to be determined. Mahima Jaini Research assistant, Dakshin Foundation Flat # A 001 Samvridhi Gardenia 88/3 Byataranyapura Post Bangalore Karnataka INDIA the role This project is conducted in collaboration with the Nature Conservation Foundation. Support for this work also comes from the Lakshadweep Department of Science and Technology, Department of Environment and Forests as well as the Department of Fisheries. Funding for this project comes from the Rufford Small Grants for Nature Conservation.