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Movement and diving behaviour of late juvenile loggerhead sea turtles (Caretta caretta) in the western Indian Ocean









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    Marine turtles along the Indian coast: Distribution, status, threats and management implications 2013
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    India has a coastline of more than 8000 km which is rich in biodiversity. Apart from sustaining fishing grounds, India’s coastal waters and beaches provide foraging and nesting sites for a variety of marine species, including sea turtles. Five species of sea turtles are known to inhabit Indian coastal waters and islands. These are the Olive Ridley (Lepidochelys olivacea), Green (Chelonia mydas), Hawksbill (Eretmochelys imbricata), Loggerhead (Caretta caretta) and the Leatherback (Dermochelys cor iacea) turtles. Except the Loggerhead, the remaining four species nest along the Indian coast. Though many of the ecological interconnections influencing sea turtle behavior and biology remain unclear, it is known that sea turtles occupy a unique position within the food web. They consume an assortment of prey, including puffer fish, crustaceans, sponges, tunicates, sea grasses, and algae. The unusual life cycle of the animal plays a vital role in transportation of nutrients from the highly prod uctive marine habitats such as sea-grass beds to energy-poor habitats like sandy beaches. This helps reverse the usual flow of nutrients from land to sea. Threats to marine turtles in India are many, and varied. Some of the major threats include unplanned beach development (including ports, lighting, tourism and plantations), by-catch mortality (in trawl nets and gill nets), weak enforcement of fisheries and Protected Area regulations and, to a limited extent, killing of turtles for meat and the poaching of eggs. The coastal state of Odisha on the eastern coast of India experiences one of the world’s largest mass nestings or arribada of the Olive Ridley turtle during the months of October to April. Three of the world’s major mass nesting beaches for this species are located in Odisha, supporting a nesting population of probably more than half a million Olive Ridleys, making this one of the most critical conservation areas for this species globally. However, there are other significant turtle populations in India, which also need to be protected and which are less known. This initiative, which builds on earlier surveys is an attempt to understand the current status, distribution and threats to sea turtles in India. It covers the coastal states of India, but due to limitations of resources, leaves out the islands of Andaman and Nicobar and Lakshadweep. We hope that this report helps to provide an understanding of the current status and trends in turtle distribution along the In dian coast. It also assesses the threats to turtle populations in each state and provides recommendations for their conservation.
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    Post nesting migration of green turtle (Chelonia mydas) in the western Indian Ocean 2013
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    Marine turtles do not recognize political boundaries, nor do they have regard for Exclusive Economic Zones (EEZ s), cooperative agreements, intertiol conventions, or memoranda of understanding between countries. So is it in the Southwest Indian Ocean (SWIO), a region that hosts some of the most important green turtle nesting sites in the world, most of which are isolated on remote islands (e.g. Europa and Glorieuses, Aldabra and Cosmoledo, Moheli and Mayotte). This region of the world is known t o have year round nesting of green turtles but all sites display a marked nesting season. However, very little is known about migratory pathways that sea turtles ply between their nesting and feeding grounds in this region where this species faces numerous threats such as fisheries interaction at both open sea and coastal waters. From 2009 to 2011, we deployed 81 satellite transmitters on nesting green turtle females during (d) and opposite (o) to the nesting peak in 5 important rookeries of the South West Indian Ocean (SWIO): Europa (Nd=10; No=10), Glorieuses (Nd= 10; No=10), Tromelin (Nd= 10; No=10), Mayotte (Nd=10; No=10) and Mohéli (Nd=7; No=3) and collected previous 24 old tracks in the area for a total of 105 tracks. First results showed that 39.7% of the tracked turtles used Madagascar costal foraging ground while more than 50% used the east African ones (Mozambique (32,0%), Kenya (3.8%), Tanzania (15,4%) and Somalia (2,5%)). It is worthwhile noting that the North Mozambique and South Tanzania remain the most important foraging ground for the tracked turtle (45% of the tracked turtles), but that they are mainly used by turtles tagged during the nesting season. On the other hand, we highlight here that green turtles also use a large range of foraging ground in the area (55% of the tagged turtles), some of them being hot spots (e.g. south of Maputo – Mozambique, Tulear lagoon – Madagascar). Spatial distribution estimation allowed identifying important year round coastal and oceanic migrating corridors: 2 oceanic corridors, (1) in the north of the Mozambique Channel (11°S - 14°S) and (2) the south of the Mozambique Chanel (17°S - 23°S), more particularly from the north of Europa to the north of Mozambique (38°E - 41°E); and 2 coastal corridors (1) The east African coast, between 16°S (Mozambique) and 7°S (Tanzania), and (2) all the west coast of Madagascar. The extreme north of Madagascar is also an important coastal migratory corridor The 105 tracked green turt les also crossed as many as nine different EEZs in the region before reaching their foraging grounds, which themselves are shared by six countries. Such spatial migrating pattern of adult green turtle, the temporal corridors and the regiol feeding hot spots identified are of high importance to implement targeted mitigating measures for artisal and industrial fisheries and encourage conservation on key foraging grounds.
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    Pilot project to improve data collection for tuna, sharks and billfish from artisanal fisheries in the Indian Ocean 2013
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    The Indian Ocean Tu Commission (IOTC), acknowledging the need for improved artisal fisheries reporting by the countries in the region, proposed a study to investigate the issues affecting these countries and possible solutions to the problems. This study concentrated on the capacity that countries in the Indian Ocean have to report artisal fishery catches on near-real time but recommendations were also made in some specific cases about semi-industrial and industrial fisheries if deficiencies wer e observed. Nine countries were visited and initial assessments made on their capacities to report catches from artisal fleets in near real-time. Speed of reporting and quality of data were investigated and recommendations made where appropriate. The countries visited capture over 87% of the total catch through coastal fisheries of the three species of interest (bigeye, yellowfin and skipjack tu) to the IOTC. Other countries were not visited for a variety of reasons. Pakistan and Yemen have impo rtant catches (6.7%) but could not be visited due to security concerns; Comoros has an IOTC- OFCF project in progress, and Oman has a good reporting system in place. The limitations of this study must be appreciated. Understanding the plethora of issues in such a short amount of time, sometimes as little as five days in a country, presents particular challenges that cannot be ignored. The amount of time spent and size of each country, complexities of the fisheries, people met, institutiol linkag es, politics, and other factors influenced the understanding of the issues by the consultant as well as the actions proposed. Much of the information collected may not be considered factual but anecdotal as on many occasions people from the same or different organizations contradicted each other and it was not always possible to verify the accuracy of their claims. In addition, the lack of consistency on how data are gathered in the same country shows that the region is a long way from having co nsistent methodologies in place. Although many artisal fisheries do not target tu due to limitations in the vessels the changes proposed here apply not only to tus, sharks and billfishes but also to the rest of species as the issues encountered with experimental design, sampling and reporting are pervasive and common to all fisheries. The objectives of the mission were 1. to meet with relevant officials including the Chief of Statistics, personnel responsible for aggregation and handling of fish eries data, and representatives at the provincial and district levels; 2. to visit various ports to determine the flow of information and possible areas for improvement; 3. to describe the issues affecting the timely report of artisal fishery data and investigation of possible solutions, implementation and costs; and 4. to recommend on data collection and magement activities that would make possible close to real-time reporting of data from artisal fisheries including implementation of pilot sam pling activities and strengthening of existing data collection and magement systems. These activities aimed to answer the question posed by the Commission on whether countries in the region, as a whole, have the capacity to report accurate catches in near-real time The short answer to the question made by the Commission is an unequivocal no. There are many issues affecting the capacity of these countries to produce not only reliable but timely statistics and in this document these concerns are a ddressed individually in the country reports. This does not mean, however, that there are no countries that with small changes and a dose of political will could report significantly improved statistics in the time frame proposed. Some of the countries visited could have reduced timelines and improved statistics if collection of fisheries data were given the priority it deserves. At this time, however, the great majority of countries cannot, or do not report, their catches discrimited by species , gear and month in the proposed timeframe of one to two weeks after the end of each month. It is necessary for IOTC to define artisal vessels as the temporary definition used in this study includes boats from semi industrial and industrial fleets. Because of the diversity and complexity of fishing fleets found throughout the region, neither size nor any other single characteristic will be sufficient to describe an artisal vessel. The definition will have to be based on a series of criteria (e.g . fulfilling three out of five characteristics that may include gear used, size of boat, size of motor, autonomy, type of storage, etc). The fleets encountered in many countries show a range of interchangeable fishing techniques, capacity to fish close or far to shore, capabilities to stay from a few to many days away from port and other characteristics that are usually associated with more developed fleets. Even if a definition by IOTC exists, countries need to define their fisheries magement u nits to clearly separate artisal, semi industrial and industrial components to avoid aggregation of vessels that may use similar gear but have different capacities (e.g. sizes, autonomy, etc) and therefore different catches. Contracting and Cooperating Non-contracting Parties (CPCs) in the region have the obligation to fulfil the requirements set by the Commission. At this time near-real time reporting is not one of them but countries should evaluate their needs and consider the suggestions give n here to improve their reporting systems. To successfully implement any activities to improve reporting systems, it will be necessary for the countries to critically assess the possibilities that they have to continue the work once support, fincial and logistical, is suspended regardless if the support is exterl or in-country. It is not very useful to realize improvements if the proposed activities are discontinued soon after support stops because the responsible departments do not assign the p riority, funds or capacity to maintain them. Ideally, these changes should be incorporated into existing structures and given the importance needed to ensure procedural continuity and high quality of data. A common problem through the region is the aggregation of species under a common label (e.g. sharks). Substantial amounts of money and time have been spent on the design, compilation and production of identification guides (e.g. FAO in Tanzania and Kenya) but they have serious shortcomings as they present one or two species from groups such as tu, a resolution that leaves much to be desired. For fisheries magement purposes, data must be collected with species resolution and these guides fall short of their intended objective. A possible replacement to printed guides is the use of electronic tablets that can be used for identification purposes as well as for data collection. The use of this technology would resolve the most common problem encountered in this mission, that of considera ble delays in report production due to hold ups in entry of data. The costs of said tablets and the development of the software in most cases would be less or comparable to the cost of purchasing laptops and other computers, photocopying forms, and mailing these to the various centres. Furthermore, the use of tablets would allow for remote supervision, thus reducing the need for on-site monitoring, as many of these tablets have GPS or other methods to determine position that allow for immediate localization and monitoring of personnel in the field. This technology, however, may not be appropriate to all countries visited, as it would need reliable Internet connection and technical support. It would be possible for countries like India and Sri Lanka to start using this technology as they have already expressed interest in its use and would address the issues presented above which are relevant to these countries. The countries visited exhibited a wide range of fisheries, gears, species, and of course issues thus they are presented individually in the country reports although general comments follow to highlight the most important findings and recommendations. India possesses one of the most complex fisheries in the region because of its size, large number of boats and people. In addition, the large numbers of landing sites make this country a challenge to sample. Nonetheless, there is infrastructure and institutiol capacity to address these concerns. The Central Marine Fisherie s Research Institute gathers data in far more detail than the State Unions and at this time harmonization of techniques and sampling by the two groups is taking place. There is no direct weighing of the catch but estimates are made visually. It is proposed that validation of this technique is done frequently to ensure the reliability of the estimates. Although there is stratified random sampling in place, it is suspected that there is substantial underestimation of the catches. There is an urgen t need to revise the stratification to allocate more sampling time to major ports. Manpower, however, is the most important issue as there are only 80 enumerators to cover 8,118 km of coastline where 1,896 ports and landing sites and 3,937 fishing villages are found. Increased sampling coverage and effort are proposed as the critical issue in India. Indonesia is one of the countries of high interest due to its geographically extensive fishery and to the large volume of fish caught. It is here pr oposed that with minor modifications to its port sampling and reporting procedures, Indonesia can report its artisal catches on time and reliably. Some of these changes include improved identification and classification of species, harmonization of datasheets throughout the various districts in the country, and reduced aggregation of data as they are passed along the chain of reporting. Although there are issues with the Indonesian fishery reporting system, there are no indications to suggest th at large underreporting is taking place. There are problems with identification of species and underreporting, not so much from omission of data as for mishandling of information. In some cases tu weights are reported from processed (gilled and gutted) animals and these weights are not converted to live weight. Although it is likely that there is some underreporting due to the size of the country and the complexity of the fishery, it appears that most of the catch is reported, albeit partly iden tified incorrectly. One of the main issues of concern in Indonesia is the catch of large numbers of small bigeye and yellowfin tu associated to “rumpons”, i.e. anchored Fish Aggregating Devices (FADs). Their monitoring is proposed as a priority. Iran is home to one of the largest fleets of gillnet vessels in the Indian Ocean and currently has the best reporting system for total retained catch sampled in port of the countries visited. Large numbers of these vessels have the capacity to fish offsh ore and there is an urgent need to separate the coastal or EEZ fleet from that one that fishes on the high seas. The system in Iran covers effectively the effort (trips) for fishing vessels in its EEZ as this is mandatory and strictly enforced, but there is the need to improve the logbook system for vessels fishing on the high seas. Enumerators interview about 10% of the fleet but the same vessels are always sampled and this could be a source of bias that needs to be addressed. In addition, info rmation on gear configuration is needed to be able to standardise the effort per fishing event, something missing at this time. An important issue for the fleet fishing in this country may be bycatch of turtles, marine mammals and birds, and this will only be address accurately with observers on board the vessels. Kenya has a small fishery for tu, sharks and billfish. Although there is basic infrastructure and personnel in place, there is a need to improve the reporting system substantially, som ething already in development by the Fisheries Department in the country, with the creation of a new sampling protocol, datasheets and database. It is necessary to have dedicated enumerators (at this time personnel work on many tasks and sampling is sporadic) and basic equipment including hardware and software. The recreatiol fishery is effectively covered and there is a working database in use that houses a large dataset although it presents problems in specimen weights as these are estimated. Madagascar’s sampling and statistics infrastructure needs a complete overhaul. This will require massive amounts of money, time and expertise, assets that would be, in this consultant’s opinion, misplaced if we consider IOTC’s interests. Furthermore, the total catches of the species of interest, except sharks, are thought to be very low. It is very likely that the foreign fleet present in the Malagasy Exclusive Economic Zone (EEZ) catches most of the tu and sharks in the country. A small longlin e fleet targets bigeye and yellowfin but the catches are relatively small and the operators appear to record their catches in detail although it is unknown what the relevant authorities do with the information. The reporting of this component needs to improve to take advantage of the detailed information collected by operators. The main concern for Madagascar’s fishery is the large number of sharks caught which in many cases may go unreported. Investigation of the unreported shark catch and how to measure it is here proposed as a priority for this country. The tu fishery in Maldives is simpler than in other countries in the region. The main gear is pole and line although handlines and trolling are also used and there are plans to introduce longline. The main species caught are skipjack and yellowfin, the latter mainly for export. There are very good records of number of individuals caught and their weights for exported fish but the same cannot be said for fish that stay for local consu mption. The large number of islands and their relative isolation make it challenging to sample and monitor the fleet. An increase in effort in the various ports and landing sites and a revision of the sampling strategy are priorities for Maldives. In addition, there is mislabelling of bigeye (called yellowfin) although the numbers are low compared to the other species. Mozambique possesses one of the best data collection systems encountered. Although the artisal fleet catches small quantities of tu, the system and the personnel in place gather data with sufficient detail about gears, species and effort to allow for detailed alysis. There are reporting problems, however, as the institutiol obligations are not clear and Mozambique does not report its artisal catches to the IOTC. The semi industrial fleet, also included here because of the IOTC definition, does not have a comparable system as catch data are collected from logbooks without verification. Furthermore, concerns exist on under reporting from this and the foreign industrial fleet fishing in its EEZ. Sri Lanka’s fishery, even if similar to India’s because both are multi-gear, multi-species, is not as complex because the country does not land as much fish in as many landing places with as many gears. The harbours visited are relatively well organized and seem fairly easy to sample. As in India, the main problem is shortage of enumerators and the fact that two institutions sample for landings with different methodologies. This leads to duplication of work and it is proposed here that one institution conducts the sampling. Although there is stratified random sampling, sampling effort is not sufficient and there is a need to cover the landing sites more intensively and extensively. Collaboration between the two institutions responsible for fisheries data collection and reporting will improve the data gathering efforts in Sri Lanka. Tanzania (mainland and Zanzibar), like Kenya, has experienced marked changes in its tu fishery. Most vessels fishing for tu were from foreign fleets but they have moved away from the area due to piracy threats in this part of the Indian Ocean. Extremely small catches of tu, billfish and sharks are reported from the artisal fleet because the boats are basic and this forces them to remain very close to shore where tu species are not found in abundance. In most cases, data from artisal fisheries (within 12 nm from shore) are collected by Beach Magement Units (BMUs) who then pass the information to their respective fisheries department for collation and production of statistics. Further training of the BMUS was identified as a priority for Tanzania. The countries that need the most urgent intervention on their current sampling and reporting methodologies are India (tus and sharks), Indonesia (tus and sharks), Madagascar (sharks), Maldives (tus) and Sri Lanka (tus and sharks). These are the countries with the highest catches of tus and sharks that currently present issues with their data collection and reporting structure. In addition to the fisheries covered in this report, there are others that are industrial and which are not monitored or reported adequately. This includes the longline fishery of India and Indonesia, gillnet in Iran, and both fishing arts by the fleet from Sri Lanka. Although logbook systems are sometimes in place, the reporting from these fleets is sporadic at best and needs substantial improvement. At present, most of these fleets would not be able to report data in near-real time as proposed by the IOTC. Even though port sampling should register most of the species caught, there are species that are discarded for a variety of reasons. Furthermore, some fleets are semi-industrial or industrial because the boats are larger than 24m or they fish outside their EEZ, but the required coverage of 5 % of fishing events is not being met and they should be monitored more closely, thus the need to implement an observer programme as required by the IOTC. This is not feasible in many of the countries due to the small size of the vessels but monitoring at sea may be possible from patrol vessels where the observer does not need to spend more than a short amount of time on a boat to document the complete catch. Fishers in the countries visited may keep all of the catch (e.g. India) or in some cases may get rid of certain bycatch species because it is illegal to possess them (e.g. sharks in Maldives) or because they have no commercial v alue (e.g. birds) but this is difficult to verify. Thus it is important to ensure that observer programmes are implemented where possible to guarantee that all species caught, and their fates, are recorded and included in regiol statistics. Many programmes have been carried out in countries in the region to support the development of fisheries magement but few, if any, have taken root and become an integral part of the way countries collect, process and utilize information. When support is given it must be clearly defined and the commitment to sustain and develop their monitoring and sampling must be secured from the receiving countries as part of this effort. It is common practice that after the period of support ends, initiatives and projects grind to a halt because of lack of funds, shifting priorities within ministries or departments, or lack of political will to continue. This model clearly does not work and the result is the loss of massive amounts of money, time and effort from aid agencies and RFMOs, therefore an altertive is needed. Collaboration with the fishing community in data gathering activities may be a possibility for some of the countries in the region such as Tanzania, but for countries with large and complex fisheries this model is not workable. In this case, governmental support in funds, personnel and infrastructure is the only way in which countries will have an independent, reliable and workable fisheries framework. The changes proposed in the country reports are applicable not only to tu, billfish and shark fisheries, but they are measures to improve reporting systems as a whole, changes that are sorely needed for the magement of all species. The key to the success of any initiative will be political commitment from the concerned countries and the need to realize the importance of fisheries magement to the stability of the fishing industry and food security, and preservation of the resources.

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