1Department of Zoology, University of Peradeniya, Peradeniya, Sri Lanka
2Department of Statistics and Computer Science, University of Peradeniya, Peradeniya, Sri Lanka
3Guangdong Key Laboratory of Ocean Remote Sensing, South China Sea Institute of Oceanology, Chinese Academy of Sciences, Guangzhou, Guangdong, China
4University of Chinese Academy of Sciences, Beijing, China
5Department of Animal Science, Faculty of Agriculture, University of Peradeniya, Sri Lanka.
The incidental catch (bycatch) and discard of non-target species in a fishery occurs when fishing gear catches species whose retention is either not economical or prohibited by law (Dayton et al., 1995). For fisheries where discard reporting for bycatch exists, rate estimates vary widely by gear type: while some fisheries have negligible levels of discards (Kelleher, 2005), other fisheries discard more than they retain. For example, the Indian Ocean longline fisheries alone have a bycatch of 37,400 tons of which a substantial proportion may be discarded (Ardrill, 2012). Bycatch in commercial fisheries can cause severe impacts to marine wildlife, especially sea turtles (Spotila et al., 2000; Peckham et al., 2007; Lewison et al., 2014). The impact of small-scale fisheries on sea turtles is currently less studied but may have a greater impact (e.g. Wallace et al., 2010; Lewison et al., 2013; Rees et al., 2016). Hence, Temple et al. (2018) highlight the need for proper documentation, monitoring and assessment of the effect of small-scale fisheries on sea turtles, especially in developing regions. Sea turtles interact with various types of fishing gear and the frequency of interactions depends on spatiotemporal overlap between critical habitat for a given species and fishing activities, encompassing a wide range of fishing methods and gear characteristics (Marcovaldi & Thome, 1999; Wallace et al., 2008) so there is value in conducting studies in different countries and national districts.
Sea turtle bycatch occurs along the western, south western and north western coasts of Sri Lanka (Kapurusinghe & Saman, 2004; Kapurusinghe & Cooray, 2002; Rajakaruna et al., 2009). These areas, especially along the north western coast, overlap with sea turtle migratory paths indicated by satellite telemetry studies of post-nesting turtles on the south and south western coast returning to their foraging grounds in the Gulf of Mannar Biosphere Reserve and the Lakshadweep Islands in southern India (Richardson et al., 2010). Sea turtle bycatch is a leading cause of mortality for the island nation’s sea turtle population (Jones & Fernando, 1968; Jinadasa, 1984). From November 1999 to November 2000, a total of 5,241 sea turtle bycatch incidents across Sri Lanka were reported in major fishing sites along the western and north western coasts. These included all five species of sea turtles that nest along Sri Lankan beaches (Kapurusinghe & Saman, 2004). But the reports may also include incidental take of turtles drowned or struck during fishing activities (Asian Fisheries Society, 1988). There were “accomplished turtle-catchers” on the northern coast who used a variety of nets to capture sea turtles (Frazier, 1980; Hewavisenthi, 1990) when there was high demand for turtle meat in the past. Reports detail the butchery and selling of live turtles openly in Kandakuliya, a village on the northwest coast where there is no sea turtle nesting but where high sea turtle interactions with fisheries occurs (Kapurusinghe & Saman, 2004; Kapurusinghe & Coorey, 2002), and other north western parts of the island (also see Kapurusinghe, 2006).
Under the Fauna and Flora Protection Ordinance (FFPO, 1938 amended in 1972) of Sri Lanka, it is an offence to capture, kill, injure or possess sea turtles or their eggs. Sri Lanka has banned the international trade of sea turtle products. This resulted in a considerable decline in slaughtering, but sea turtles and their eggs continued to be exploited in some parts of the country (Hewavisenthi, 1993; Richardson, 1995; Kapurusinghe & Saman, 2004). Until the mid-1990s, the most widespread forms of sea turtle exploitation were the collection of eggs and killing of adults for their meat and scutes (de Silva, 1996). The FFPO was amended in 1993, increasing the punishment for offenders and resulting in fewer killing of sea turtles for their scutes to produce ornaments (de Silva, 2005). However, a survey in 2009 suggested that some people in Kandakuliya continued to eat, buy and/or sell sea turtle meat (Rajakaruna et al., 2009). All of this suggests that some sea turtles were still caught purposefully and sold for cash.
Although legislative measures were in place to control the killing of turtles for meat and eggs, the civil war from 1983 to 2009 made it difficult to enforce such measures in the north. However, following the cessation of the armed conflict in 2009, strict enforcement of this legislation and close monitoring was possible. A more recent survey carried out in 2014 indicated that incidental capture of sea turtles at two fishing sites on the west coast (Negombo and Beruwala) was very low, at ~0.009 animals per boat per month (Maldeniya & Dhanushka, 2014). However, these authors highlight remaining challenges related to gear types and sea turtle bycatch; for example, gillnet fisheries had a low sea turtle interaction rate relative to longlines but relatively higher numbers were reported dead in gillnet fisheries than in longlines.
The compulsory adoption of Indian Ocean Tuna Commission (IOTC) Resolution 12/04 for the Conservation of Marine Turtles further highlighted the importance of accurate quantification of turtle bycatch (Fisheries Statistics, 2014). The IOTC resolution recognized that some fishing operations carried out in the Indian Ocean were adversely impacting sea turtles and reflected the need to implement measures to manage the adverse effects of fishing on sea turtles in the Indian Ocean. It also notes the IOTC Scientific Committee’s concern that the expansion of gillnet fishing from traditional fishing grounds into high seas might increase undesirable fisheries interactions with sea turtles and lead to increased mortality. It is important to ensure that fishers are aware of the ecology and behaviour of sea turtles, as well as bycatch legislation so that they are not only aware of related rules but also understand the rationales for them. Here we investigate perceptions and attitudes of fishers, as well as related practices, in three fishing villages- Negombo, Kandakuliya and Palali- and consider how the resulting data can be used to inform sea turtle conservation in Sri Lanka.
Figure 1. Map showing the three study sites in the western, north western and northern Sri Lanka.
and to add new data on fisher knowledge, perceptions, and practices as they relate to sea turtles. Based on previous turtle bycatch data (Amerasooriya, 2000), three fishing villages: Negombo in Gampaha District (Western Province), Kandakuliya in Puttalam District (North western Province), and Palali in Jaffna District (Northern Province) were selected to comprise the overall study site (Figure 1). No sea turtle nesting has been recorded in these areas. Rather, these areas were chosen for their bycatch levels (Kapurusinghe & Saman, 2004; Kapurusinghe & Coorey, 2002; Rajakaruna et al., 2009).
Fisheries in Sri Lanka contribute only 1.3% to the total Gross Domestic Production (GDP) but play a major role in providing livelihoods to over two million people directly and indirectly. Marine fish production by fisheries in metric tons for the three selected districts was 31,150, 32,260 and 41,890 and the number of operating fishing boats were 4,643, 6,676 and 5,095 in Negombo, Jaffna and Puttlam districts, respectively (NARA, 2016). Drift gill nets are the most widely used gear type. Fishing boats/ crafts fall into six categories (NARA, 2017): inboard multi-day boats, inboard single-day boat, out-boat engine fiberglass reinforced plastic boats, motorised traditional boats, non-motorised traditional boats and inland fishing crafts.
Both men and women are involved in the fishery industry in Sri Lanka. The role of women in the fishing communities varies in different geographic locations. On the north western coast, women own and rent fishing equipment and actively participate in fishing. In other areas women participate in fish trading, fish processing and net mending. But the majority of the women in fishing communities are responsible for care of the children and domestic chores (Marine Small-scale Fisheries of Sri Lanka- FAO, 1984).
For the study, fishers were recruited using a snowball sampling method which involved first identifying potential subjects in the population and asking those subjects to recruit other people and ask those people to recruit again. A questionnaire, consisting of 60 open and closed ended questions, was pre-tested before data collection. Informed, verbal consent was sought from participants after the objectives of the study were explained to them and anonymity was guaranteed. If they agreed to participate, they were interviewed in the local vernacular (Sinhala or Tamil, via the use of a translator). During the interview, first the fisher’s demographic information (age, sex, number of household members, education level, income source, monthly household income level, years of fishing experience, whether at least one parent or grandparent had been involved in fishing) was collected. Then, questions were asked to assess their local ecological knowledge about sea turtles, fishing practices, fishery-related experiences with sea turtles, knowledge about sea turtle bycatch, and their perception of sea turtle conservation and legislation. The original and unique perspective of the respondent was recorded during open ended questions and the response categories were later identified using inductive reasoning following Grounded Theory.
Respondent demographics and other data for the three villages were compared using a Chi square test when the sample size allowed and Fisher’s exact test in other cases. The data were also examined for relationships among demographic characteristics (e.g. education) and response variables such as ecological knowledge, fishing practices, and perceptions of sea turtle conservation.
RESULTS AND DISCUSSION
A total of 67 fishers were interviewed across the three fishing villages: Negombo (n=20), Kandakuliya (n=32) and Palali (n=15). Each interview lasted 30-40mins.
All the respondents were men and were mostly aged between 30-55 years old (82.1%; Table 1). On average, the majority had only primary education or less (84.1%; Table 1). Among the three villages, the respondents in Kandakuliya had significantly lower levels of formal education (96.7% only up to elementary level; Fisher’s exact test, p=0.015). Fishing communities in Sri Lanka, like other rural populations, often have reduced access to literacy and formal education compared to their urban counterparts (Maddox, 2007); hence, literacy is far below the national average as the majority of children do not proceed beyond primary school, and a small percentage (~11%) do not have any formal education (Fisheries Statistics, 2014). Some scholars have suggested that lower levels of formal education in Sri Lanka are problematic for sustainable utilisation of resources in the fisheries sector (Herath & Radampola, 2017). Fisheries Statistics (2014) showed that although the number of active fishers engaged in marine fishery industry had been gradually increasing, levels of formal education remain low, for most fishers. This is similar to the other south Asian countries like Bangladesh (Islam et al., 2013; Galib et al., 2016). Some see low literacy rates and reduced access to education as a challenge as there is a widely held view that low literacy rates, and widespread educational disadvantage in artisanal fishing communities are a barrier to many aspects limiting the agency of women, people’s ability to diversify, to improve their business activities, benefit from extension advice and so on (Maddox, 2007 and references therein). However, Maddox (2007) showed that illiteracy is not necessarily an occupational hazard of fishing livelihoods. How low literacy affects the success of community-based sea turtle conservation interventions in Sri Lanka is unknown.
Fisher families were small to medium, usually comprising seven household members (Table 1). For many respondents (95.0%), fishing was their sole source of income. This was especially the case for respondents in Kandakuliya (100%), who generally had a monthly income of less than 350 USD per family. Poverty in fisher community is due to the vicious cycle of that they are prone to low levels of schooling (Maddox, 2007) and this cycle has a strong connection to the old paradigm “they are fishermen because they are poor”, and “they are poor because they are fishermen” (Bene, 2003). Most fishers (79.2%) had more than 10 years of experience in fishing, which can be described as a father-son profession whereby the grandfathers of all the fishers interviewed and 94.0% of their fathers had also been fishers (Table 1). For them, the fishery is a component of their personal and family heritage and is valued as very important to their livelihood, although the income was low and unsteady.
Table 1. Demographic information of study respondents in the three fishing villages. NG- Negombo (n=20), KL- Kandakuliya (n=32), PL- Palali (n=15).
ECOLOGICAL KNOWLEDGE ABOUT SEA TURTLES
While most respondents had many years of fishing experience, only 41.8% reported that they had seen sea turtles. Turtle sighting occurred while fishing (87.2%) or while travelling to fishing sites (12.8%; Table 2), mostly from October to December (53.8%). No respondents reported having seen sea turtles between July and September, potentially as the breeding seasons of the two most abundant sea turtles in the area, green and olive ridleys turtles, occurs between February to May and November to February respectively (Ekanayake et al., 2010; Jayathilaka et al., 2017).
When asked about different species of sea turtles, fishers specifically mentioned the “leatherback turtle and others”. A large percentage of fishers (61.4%) were unaware that the sea turtles were air breathers. This is important information as fishers assume that the turtles caught in their nets are able to breathe underwater, and presumably leave entangled turtles in their fishing nets instead of removing them or reducing soak times. Sea turtles can stay underwater for 2-5 hours (Byles, 1988) and the breath hold duration increases with age-class (Lutcavage & Lutz, 1997). The intensity of bycatch of air breathing megafauna varies substantially within and among gear types (Lewison et al., 2004a,b).
The majority of fishers claimed that they see fewer turtles now than in the past (64.6%). Whether this means that the number of sea turtles has decreased over the years or that fishers have less interest in sea turtles due to increased punishment for those involved in catching or selling sea turtle meat, has to be determined. Nevertheless, the number of turtle encounters often depends on factors like the time of year, weather, surrounding habitat, and geographic location (Nguyen et al., 2013).
Most of the respondents engaged in fishing every day of the week (90.9%) and the majority throughout the year (74.6%; Table 3). Most fishing occurred at night (67.2%). Respondents were either the owner of the boat (48.4%) or a crew member in the boat (51.6%). The number of people in the boat varied but usually consisted of two members (69.8%), and most boats fall into the category of small-scale fishery category (90.5%) but were motorised (93.6%). These boats were operated mostly in lagoons and, with over 100 such water bodies in Sri Lanka, lagoonal small-scale fisheries are particularly abundant (Silva et al., 2013). The majority of the fishers were active for 1-5hr of fishing per day (67.2%) but a small proportion was engaged for more than 15hr (5.2%; Table 3).
Fishers used a wide range of gear types and, among those interviewed, equal proportions of fishers used a single type of gear (50.0%) to those using mixed gear (50.0%). The mesh size, length of the net and the position of the gear varied in the water column (Table 3). Three gear-types have been identified as catching sea turtle, gillnets, prawn/shrimp trawls and longlines (Bourjea et al., 2008; FAO, 2010; Wallace et al., 2013), among which gillnets are known to have the highest interaction rates with sea turtles and to have exerted a significant pressure on sea turtle populations throughout the Pacific (Wallace et al., 2010; Alfaro-Shigueto et al., 2011; Lewison et al., 2014). Among gill nets, the bottom-set gill nets are reported to have the highest sea turtle bycatch (Temple et al., 2019). Murray (2009) reported that bycatch loggerhead turtles can become entangled or entrapped by mesh of different sizes.
Bycatch mortalities can be decreased by gear modifications and changes to fishing practices, such as limiting soak time (Carruthers et al., 2011). For example, loggerhead sea turtle bycatch in the Atlantic longline fishery increased with an increase in total soak time (Watson et al., 2005). The success of initiatives to change fishing practices would be dependent on fisher attitudes, compliance, and enforcement.
Table 3. Fishing practices of respondents in the three fishing villages. NG= Negombo (n=20), KL= Kandakuliya (n=32), PL= Palali (n=15).
FISHING PRACTICES AND PERCEPTIONS OF TURTLE BYCATCH
Most fishers reported that sea turtles became entangled in their fishing gear (78.5%). Entanglements were usually accidental (89.4%) but sometimes were purposeful (2.1%) or context-dependent (either accidental or intentional), the latter dependent on their catch for the day or trip (Table 4). None of the respondents in Negombo claimed that they purposely catch sea turtles, but 4.1% and 2.1% of those from Kandakuliya and Palali respectively, said they did. Moreover, a sizable percentage of all respondents (42.9%) claimed that they used to catch sea turtles purposely in the past while fishing. This was also reflected in the percentage of fishers who eat sea-turtles, which has reduced from 20.5% in the past to 10.6% at present. It was noted that the majority of the fishers who used to catch, eat and sell turtles in the past were mostly older and claimed that it was traditional. These older fishers claimed that turtles caught in fishing gear were either eaten (29.5%), and/or sold in the open market to meet cash needs (11.4%) in the past but are now still consumed (10.6%) but no longer sold because of the increased punishment. During the interview fishers mentioned that in some families, younger generation would not consume turtle meat if they had been given as they consider it exotic. Such resistance and lower demand for the meat likely impose limits on the potential market for turtle meat in the region. In addition, the number of fishers currently involved in eating and/or selling turtle meat is significantly lower in Palali when compared to Negombo and Kandakuliya (Fisher’s exact text, p = 0.011). This could be because Palali was a severely war affected area and located in high security zone, with a military camp in the vicinity and “regular patrolling of Navy officers in the area”.
Police and coast guard officials monitor fishers’ activities and bycatch (63.5%). During routine patrol, the Sri Lanka Navy arrest fishers using illegal fishing practices such as using explosives and those involved in fishing without permits. Recent reports include twelve fishers in Tricomalee and Chammala (May 7, 2019) and three fishers in the sea area of Palliyawatta in Kalpitiya (March 19, 2019) for using illegal nets and ten people from Negombo and Kalpitiya area apprehended for illegal fishing (http://news.navy.lk/eventnews/). Some fishers from Negombo claimed that they had informed the police about illegal turtle catching (13.2%). As described by Hall (1996) and Ferraro & Gjertsen (2009), encouraging voluntary stewardship of sea turtles through education and incentive programs is likely to yield positive conservation results.
The number of turtles caught in the fishing gear varied among respondents, with claims that “some years they may not have caught any but for some years it could be as high as twenty or more turtles per year” (Table 4). The percentage of fishers who discard their turtle bycatch has also increased from 70.5% to 89.4% (Table 4). In 2014 Maldeniya and Danushka reported incidental catch rate (catch per boat) is as low as 0.009 catch per boat and when extrapolated to the total estimated effort it is ~103 per month. This is much lower than from similar surveys in the Mediterranean that showed small-scale fisheries were responsible for approximately 60,000 sea turtle captures/year, or 45% of the total turtle captures estimated for the regions; fisheries (small-scale and commercial; Casale, 2011).
RESPONDENT KNOWLEDGE ABOUT LEGISLATION, AND ATTITUDES AND PERCEPTIONS TOWARDS SEA TURTLE CONSERVATION
The majority of respondents (87.7%) did not report any accidental bycatch by themselves or others to the authorities (Table 5) although catch data regulations of Sri Lanka require fishermen to maintain a logbook during fishing operations and record daily catch data of a fishing trip. Hence, the data on sea turtle bycatch in Sri Lanka is scarce. Fisheries and Aquatic Resource Act No 2 of 1996 is the main legal instrument that asserts the rules and regulations for all fishing operations in the Sri Lankan Exclusive Economic Zone (EEZ), especially assert the rules for fishing operations in the high seas. Fishers are supposed to record the date of net setting, setting position (latitude and longitude) size of gear, number and weight of fish caught. If fishers were made aware of the importance in turtle conservation, incidental bycatch reporting can be successful. It is important to convince fishers that reporting turtle bycatch does not present a threat to their fishing opportunities and livelihood. Fishers should be encouraged to adopt bycatch reporting as voluntary stewardship rather than enforced requirement. However, a few fishers said that if reporting turtle bycatch was made mandatory, then more would oblige.
Although all the respondents in Kandakuliya and Palali were aware that it is illegal to kill sea turtles intentionally, significantly fewer fishers in Negombo (16.7%) had the same awareness (Fisher’s exact test: p=0.038). Nevertheless, there was no significant difference among fishers in the three villages in the knowledge that sea turtles were legally protected animals (Fisher’s exact test: p>0.05. Knowledge about sea turtles protected status and legal status did not vary with fishers’ level of formal education (Fisher’s exact test: p>0.05). Level of education also had no influence on their responses to questions on consumption and/or selling of turtle meat (Fisher’s exact test: p>0.05).
Although the majority of the respondents (65.6%) said that there were no specific customs or beliefs of eating sea turtle meat, the community in Kandakuliya had strong beliefs (34.4%), including that “eating turtle meat has health benefits such as it is good for back pain, hernia, haemorrhoids and arthritis” and that “turtle meat provides energy and strength”. People in Kandakuliya also said they like to eat the turtle meat because it is “tasty”. At the same time, some respondents from the same village did not like eating turtle meat because they did not like killing turtles or because they believe sea turtle meat cause allergies.
Overall, fishers had a positive attitude towards sea turtle conservation and feel that it was necessary to conserve them (71.9%). Most respondents did not feel that they have lost income due to turtle conservation legislation (85.9%). This could be because that they have occasional contact with turtles and consequently the probability of damage caused by turtles was low. This is in contrast to a study on small-scale fishers’ interaction with sea turtles in Crete, Greece, reporting catch of 111 to 123 sea turtles during a 12 month period and that fishers consider these interactions with sea turtles and other marine megafauna as a large problem affecting their livelihoods (Panagopoulou et al., 2017). The majority of our study respondents (77.1%) not only mentioned that it was important to have sea turtles around and but also felt that it was fair to have penalties for killing turtles (71.4%). Among the fishers interviewed, 5.3% had been punished for catching or selling sea turtles. Overall, 75.8% had eaten turtle meat. Among the three villages a significantly higher number of fishers from Kandakuliya village claimed that they had consumed turtle meat (Fisher’s exact test: p = 0.011). More than half of the fishers interviewed (53.6%) feels that there is still demand for turtle meat. There was no significant difference for the demand for turtle meat among the three villages (Fisher’s exact test; p>0.05).
Table 5. Knowledge about legislation, attitudes and perception towards sea turtle conservation of the fishers in the three fishing villages. NG= Negombo (n=20), KL= Kandakuliya (n=32), PL= Palali (n=15).
Although consumption of sea turtle meat by the coastal communities still remains in some areas of Sri Lanka, like Kandakuliya, despite the strict laws prohibiting the harvest and use of sea turtles, the majority of the fishers knew that sea turtles were illegal to kill and was aware that there were monitoring of sea turtle bycatch. Since the three villages from which we drew our respondents are relatively poor, sea turtle meat sometimes not only provides food for an individual’s household but can also bring economic benefits via sale at the market. Answering the question “How much is too much?” is the important issue. The percentage of fishers who release bycatch and were aware of legislation had increased in comparison to previous studies, and deliberate captures and demand for meat had decreased with no reports of meat being sold in the open market. Over the years, fishers seem to have improved practices and have a better understanding of the threats of sea turtle bycatch and importance of conservation.
Above information on fisher practices and perceptions on sea turtle bycatch were collected by interviewing the respondents. What the respondents claim at an interview may not necessarily be what they practice and dishonesty can be an issue especially when they were aware that the questions were based on threatened, protected species.
Peradeniya University Grant # RG/2014/40/S provided financial assistance for the study. Praveena Jeganathan and Santhushya Hewapathiranage are acknowledged for assistance in conducting interviews in the local languages of Sinhala and Tamil.
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