'*'"w,'###;,;i1";: j'"il,';;*ff li''"' Decline of the Leatherback Population in , MalaysiarL956-1995 ENc-Hrnc Cnaur alu Hocr-Cnlm Lrnwr

TSEATRU (SeaTurtle ResearchUnit), Faculty of AppliedScience andTechnology, Universiti KolejTerengganu, 21030 KualaTerengganu, [Fax:609-669-6694; E-mail: [email protected]]

Ansrr-acr. - The leatherback population in Terengganu, Malaysia is now severely depleted, with current nestings representing less than l7o of levels recorded in the 1950s. Major causes of decline are mortalities attributed to fisheries operations in the high seas as well as within the territorial waters of Malaysia, and a long history of egg exploitation. These problems have been compounded by loss of suitable nesting habitat due to tourism-related development, marine pollution, and sub-optimal hatchery practices leading to reduced hatch rates and sex-biased hatchling production. The global moratorium on driftnet fisheries and complete protection of eggs to ensure optimal hatch rates and production of hatchlings with balanced sex ratios offer some hope for the eyentual rehabilitation of the depleted population. Kuy WoRDs. - Reptilia; Testudines; Dermochelyidael Dermochelys coriaceai sea turtle; nesting trendsl threats; hatchery practicesl conservation; management; Terengganu; Malaysia

The leatherback population of Rantau Abang, from 1919 to 1984. The Fisheries Department of Terengganu Terengganu, Malaysia, was celebrated as the only remaining initiated systematic collection of nesting statistics in 1984, leatherback population of importance in the world in the and thereafter data became available for different tendered 1950s (Wyatt-Smith, 1960). However, the once healthy total beaches on a yearly basis. of over 10,000 nests per year (in 1956) has collapsed to fewer After collating data from the various sources, popula- than 100 (averaged from 1993-95) in recent years. This tion trends became apparent (Fig. 1). The decline from 1956 tragic decline is a classic example of the plight of a modern- to 1995 has been precipitous, with 1995 nestings (37) day endangered species. representing only 0.4 Vo of the levels recorded for 1956 The dramatic decline of the Rantau Abang population (10,155). The annual decline averaged 260 nests per year spanning the last several decades has been well documented over the 39 year period. by Malaysian scientists (Brahim et al., 1987; Chan, 1987 a, Three-year running averages of nestings have been 1987b, l99I; Chua, 1988a). This decline, brought to the calculated to smooth out yearly differences in the declining attention of local authorities in the late 1980s, has caused trends (Fig. 2). The single data-year of 1956 has been much concern, resulting in the intensification of conserva- omitted here. As shown in the histogram, there have been tion efforts. Whether or not attempts to save the population two periods of especially sharp declines, one from 1972-7 4 from extirpation bear fruit remains to be seen. and the other from 1918-80. This paper collates available information on the Rantau Between 1972 and I97 4, the rate of decline averaged Abang leatherback population to date, analyzes causes of 723 nestings per year or 2IVo annually. This period coin- population decline, and discusses the developmenJ and evolu- cided with the period of rapid development in the fishing tion of conservation measures for the leatherback in Malaysia. industry in Terengganu. Trawling was first introduced to the state in the early 1970s and thereafter, marine fish landings NESTING TRENDS increased dramatically (Ministry of Agriculture Malaysia, I978). The negative impact of fishing gear on leatherbacks Temporal Trends from 1956-95 The earliest quan- and other turtles in Terengganu has been documented by tification of leatherback egg production in Terengganu re- Chan et al. (1988). sulted from a survey conducted by Hendrickson and Alfred B etween 1 97 8 and 1 9 80, nestings dropped at an aver age in 1956. The estimated annual egg production was 853,000 rate of 469 nests per year or 3IVo annually. This coincided e-s,_qs (Hendrickson and Alfred, 1961) or 10,155 nestings, directly with the introduction of the Japanese high seas squid assuming an average clutch size of 84 eggs (Chua and driftnet fishery of the North Pacific in 1978 (Yatsu et al., Funado, 1988). Between 1956-66, no records were avail- 1991). This fishery is presumed to have impacted the Malay- able. In 1967, the Fisheries Department of Terengganu sian leatherback population, since tagged individuals from initiated a tagging program which lasted ten years, providing Rantau Abang have been recovered from as far away as records of annual nestings between196T-76 (Chua, 1988b). Taiwan, Japan, and Hawaii (Leong and Siow, 1980). Similar [.-,]]Lxing this. Siow and Moll (1982) reported an annual fisheries operating within the South China Sea must have prrrtlus-titrn of 194.000 eggs (or 3500 nestings) in 1978, compounded the problem. After these two periods, rates of b;-3d rro inten'ieu's with licensed egg collectors. Subse- decline averaged64nests per year or 167o annually, suggest- :r--:tr .un.i\.s ( Siti and de Silva, 1985) yielded nesting data ing continuing threats from fisheries operations. CHnN AND LrEw Leatherbacks - in Terengganu r97

not shown the same decline, but instead appears to har e be e n t roughly stable between 1984 to 1994.This anal1'sis poinrs ro 10000 lU two possibilities; either only the population within the sAnc- tuary area is suffering the bulk of the decline, or rhe deciine U)t o 8000 is uniform in Terengganu, but is manifested only' u ithin the 1 F sanctuary area because of emigration of turtles to beuche . a located south of the sanctuary. Although leatherback.. l.U 6000 lik: z other sea turtle species, exhibit some reproductive philop.lrn lJ- o (nest site fidelity), straying or switching to other ne rri:S 4000 & beaches ranging from a few to over 100 km apan have t e lU ::r 6 documented. Pritchard ( 1973) reporte d 14 cases of learhe:- f backs which displayed counter-current intra-seas11r.;. z internesting shifts between Surinam and French Gui;L;

beaches 100- I20 km apart. Likewise, Eckert et al. r I 9 S q 1e6o 1e64 1e68 1e80 1e84 1 ,rtirlxh reported that 0-27.37o of the nesting population in the \\'es: Indies shifted to other beaches or islands each year. ,,,...: Figure 1. Nesting trends in the Terengganu, Malaysia, leatherback distances ranging from 30-90 km. once a switch had t e ::. population from 1 956-95. made, the turtles did not subsequently return to the beach ,_ . initial choice (Eckert et a1.,1989). In the Rantau Abu:l The pattern of decline from 1967 to 1995 can be population, Chan et al. (1991) found one radio-track:: represented by a quadratic equation (Fig. 3) : leatherback straying more than 20 km to lay a subsequi:^: clutch of eggs. y = 80.662 - 3.526t + 0.0371t2 Since the entire Terengganu leatherback popularion :. subject to similar pressures in the open-ocean environmen:. with a mean square error of 64.989 and where y = J"^tt"gt it is more likely that the overall population has suffered the and 1 = (year - 1966). Based on this equation, it is predicted decline exhibited, rather than just the animals nesting in th; that population extirpation may occur in the year 2003 if sanctuary. Based on the additional evidence of nesting beacl. present trends persist. However, trend reversals in leather- switches, we hypothesize that nesting beaches south of the back populations of St. Croix (Dutton and McDonald, 1992; sanctuary are also losing turtles at similar rates, but that the rr Boulon et al., 1996) and Tongaland (Mrosovsky, 1983; rates of decline are buffered by arrivals of sanctuary turrles Hughes, 1996) following beach protection offer some hope which have switched nesting location. In Terengganu, onlr to the depleted Rantau Abang population. the sanctuary area is subject to tourism and hence human Spatial Trends from 1984-95. - Locations of leather- disturbance. The Government Reserve area, once the site of back nesting beaches are shown in Fig. 4 while Table I highest nesting activity (Chan, 1987b) is now an open-access provides nesting statistics for the beaches between I 984-95. areawhere vendors and tourists are allowed free access. Beach The Rantau Abang Turtle Sanctuary ( 14 km long) comprises Rantau Abang I and II and the Government Reserve, which is a 0.5 km stretch reserved for egg collection by the Fisheries Department. 5000 Cumulative nesting data from 1984 to 1995 show that G, the sanctuary is the most important nesting site, accounting r! 4000 for over 707o of the total nestings in Terengganu. However, (n L9 a year to year analysis shows that sanctuary nesting contri- = 3000 F U) butions have declined in recent years. Between 1992-94, lJ.J sanctuary nestings accounted = 2000 for only 2948Vo of the total LL nestings, compared to 80-847o from 1984-86 (Table 1). In C) &, 1 000 1995, however, sanctuary nestings accounted for 68Vo of €r! total nestings. Nestings north of the sanctuary are relatively = = 0 insignificant, accounting for only 3-157o of total nestings.

Beaches south of the sanctuary, however, have shown in- -1000 1965 1968 1971 1974 1s77 1980 1983 1986 19E9 1ss2 19e5 cre a s i n.-s pe rcentage contribu tion s, parti c u I arly from 1992 to YEAR 1994 when contributions have ranged from 43-67 Vo of total nestin-us for the state. Figure 2. Declining trends in the Terengganu, Malaysia, leather- The overall decline in the Terengganu leatherback back population based on 3 year running averages of nestings. Line population is due primarily to nesting trends within the graph shows the average number of nestings per year while the histogram depicts rates of annual decline by average number of sanctuary area, and to a lesser extent, along the beaches north nestings per year, with negative numbers indicating population of the sanctuary. Nesting density south of the sanctuary has 198 CHpl-oxnx CoNSERVATToN AND BroLocv, Volume 2, Number 2 - 1996

Chan et al. (1988) provided the earliest estimates of turtle mortalities in fishing gear (mostly trawl and driftnets) in Terengganu, followed by Jabatan Perikanan Terengganu (1989) which highlighted threats posed by large-mesh gill nets for the capture of rays. More recently, sunken fish traps have been identified to be especially dangerous to leather- back turtles (Mortimer, 1989; Chan and Liew, I990a). Gravid females are particularly vulnerable to the local fish- la ery during the nesting season when they reside in inshore I r-o 12, I r-r waters for long periods. lt!t; Besides the adults, newly emerged hatchlings are also q vulnerable to fishing activities near the nesting beaches, especially those that utilize bright lights at night. Hatchlings are strongly phototactic and when released into the sea at night, they would swim towards lighted fishing boats instead 1970 197s 1980 1985 1990 1995 2000 2005 2010 of heading straight towards the relatively safer offshore YEAR waters (Chan and Liew, 1990a). Figure 3. Quadratic trend analysis of Malaysian leatherback Fishing gear impacts need to be addressed at both the local nestings, predicting possible population extirpation by about2003. and international levels. If mortality of adults and sub-adults is not reduced, even complete protection of eggs at the nesting chalets with unshielded lights have been built there to provide beaches would be rendered ineffective (Wetherall et al., I 993). accommodation and other facilities for tourists. Past Patterns of Egg Exploitation Coastal villagers The highly publicized Rantau Abang Sanctuary is vis- in Terengganu have been engaged in the collection of ited by thousands of tourists during the nesting season, with leatherback eggs for consumption and sale since time imme- up to 1000 people watching a single nesting turtle (1ters. morial, with egg harvests approaching 1007o for many obs.). Through the provisions of the Turtles Enactment 195 1 decades. Egg harvesting became an organized, state-con- (Amendment) 1987 , turtle watching is subject to rules en- trolled economic activity with the promulgation of the forced by officers of the Terengganu Fisheries Department. Turtles Enactment in 1951. The enactment provided for the However, because of large crowds and limited enforcement division of nesting beaches into lots, with each lot tendered personnel, turtle watching rules are more frequently flouted to the highest bidder. than followed. As a result, tourism and its related activities It was only in 1961 that the first hatchery for leatherback remain a major disturbance within the sanctuary. Further- eggs was established (Hendrickson, 1962). However, as more, sanctuary personnel conduct all-night patrols through- evidenced by the population crash today, the hatchery pro- out the sanctuary beaches using noisy ATVs (all terrain gram has been ineffective in sustaining the population. The vehicles) with strong headlights. With such intense distur- state government has banned the commercial sale and con- bance, it is not surprising that the turtles have switched to sumption of leatherback eggs since 1988, with close to 1007o more conducive and remote sites. of the eggs deposited retained for incubation (Table 2). Past Hatchery Practices. Hatchery operation as a CAUSES OF POPULATION DECLINE conservation technique has failed- to sustain population levels in Rantau Abang. The ineffectiveness of the practice Inciclentctl Captures in Fishing Gear. The pelagic has been attributed to low percentages of eggs incubated in nature of leatherback turtles throughout their- life history the early years of the hatchery program (Table2),poor hatch renders them extremely vulnerable to fishing gear in interna- rates, and high temperature regimes in hatcheries, resulting tional as well as territorial waters of coastal states. Wetherall in strong female-biased hatchling production (Chan, 1991). et al. (1993) estimated that the Japanese squid driftnet Hendrickson and Alfred ( 1961) estimated that as little as fishery in the North Pacific accounted for the death of over 27o of total egg production could provide the necessary popu-

200 leatherback turtles in 1989, while Yatsu et al. (1991) lation recruitment while Siow and Moll (1982) suggested 1 57o. reported that the same fishery killed over 500 leatherbacks In a healthy population, C. Limpus Qters. comm.) estimated in the two year period from 1989-90. Given the highly that at least 707o of the eggs be protected to sustain population misratory habit exhibited by leatherbacks and records of size. For severely depressed populations, it is critical that all ricr)\'€n' of Rantau Abang-tagged individuals in the South eggs be protected and optimal hatch rates ensured. China Sea and North Pacific (Leong and Siow, 1980), it is Records of actual numbers and percentages of eggs .rirtt..>t certain that these driftnet captures involve the Malay- incubated, numbers of hatchlings released, and hatch rates .i:,.n prrpulation. at least in part. are shown in Table 2 and Fig. 5. Between 1966 and 1976, The rapid de'u'elopment of the fishing industry in good numbers of hatchlings were released from Rantau T:renssanu s'ithin the last three decades has also been a Abang. Assuming a 20 year maturation period for leather- r:'i;lt-rr facte-rr in the decline of the Malaysian leatherback. backs, these hatchlings should already be recruiting into the CHnN AND LIew Leatherbacks in Terengganu r99 -

6o00 t

t'1,-Pulau Bedang

ulo

SOUTE Sekeping CEIf,A laga Papan SBA

0 hrlau Kapas

5ooo t obu BoagL,ok Rhu Kubur Rantau ,'Rantau \/G9Yer@Tl Resg Abang I Alagg-{- ) Rantau lbang II

Pats Syaritat Bhu Kudung Tanjung Batu

I "t i antai !.-., , ?' ; Tanjung I ) (''4..,'''-'-'-'r.- kn 'ar\ 'l 't'-'l

Figure 4. Location of leatherback nesting beaches in Terengganu, Malaysia. The Rantau Abang Tunle Sanctuary extends from Rantau Abang I to Rantau Abang II. breeding population. However, persistent population de- transported to the hatcheries within three hours of oviposi- clines indicate no evidence of recruitment. Given the highly tion. Chan (199I, 1993) partially attributed low hatch rates pelagic nature of leatherbacks throughout their life history, to egg infertility. Between l98l-91, about l8.8%o of the the thousands of Rantau Abang hatchlings released may clutches were found to be completely infertile, while within have eventually fallen prey to high seas fisheries operating fertile clutches, an average of 30.5Vo of the eggs were in the South China Sea and North Pacific. By comparison, infertile. After accounting for inter- and intra-clutch infertil- green turtles which spend only the first few years of their life ity, it was estimated that hatch rates attainable in Rantau in the pelagic zones have staged an impressive population Abang could not exceed 56.4Vo (Chan, 1993). recovery in the Sabah Turtle Islands since 1988, after ap- The hatcheries in Rantau Abang have been postulated to proximately 2}years of intensive hatchery operation (Basintal previously produce hatchlings which were practically I00Va and Lakim, 1994). female (Chan and Liew, 1995a). Since all hatchlings re- Current population levels in Rantau Ab ang represent leased have been produced from hatcheries, the resultin-u only about IVo of levels in the 1950s. It is clear that unless adult population would be male-impoverished. In such a leatherback mortalities in high seas fisheries can be effec- scenario, female turtles which do not have adequate mating tively controlled, the 1007o egg incubation practiced now chances will eventually deposit eggs which are largely infer- cannot significantly rehabilitate the population. tile. Egg infertility due to sex-ratio imbalance has indeed There has been a general decline in hatch rates attained emerged as a unique problem in Rantau Abang and presents alt in the Rantau Abang hatcheries even though hatchery prac- additional constraint to the survival of the population. tices have improved. Based on the finding that leatherback Tourism-Related Activities and Switching of Yc'trir..' eggs can withstand rough handling only within five hours of Beaches. - Although the leatherback population in Rant:,u oviposition (Chan et al., 1985), sanctuary eggs are now Abang has been severely decimated, its nesting bea.-itl. r00 CHploNrAN CoNSERVATToN AND BroLocy, Volume 2, Nuntber 2 - 1996

Table 1. Annual leatherback nestings along tendered beaches in Terengganu from 1984-95. Beaches are listed from a south to north Jrrection. (Source: Fisheries Department of Terengganu). Tendered Beach 1984 1985 1986 1987 1988 1989 1990 l99l 1992 1993 1994 1995 Total

Southern Beaches I Geliga 0 t22 0035 0 80 0 2T I Tanjung Mengkuang 0 000 0050 0 00 0 5 3 Senanjang 0 200 2100 0 00 0 5 + Kijal 0 6114 15 0 12 5 t9 824 0 tt4 5 Pantai I 000 0000 0 00 0 I a 6 Pantai 0 s00 1001 J 07 0 T7 7 Penarik 1 000 0000 0 00 0 I B Ma' Daerah 18 3 23 13 254n2 t2 021 0 138 9 Chakar Hutan l1 360 12r74 5 014 0 63 l0 Tanjung Batu 0 0143 13 2 6 8 7 43 0 60 1 I Rhu Kudung I 210 l0 12 13 4 8 55 I 62 12 Kebun Pakar Syt. 4 001 1234 t4 22 3 36 13 Kuala Paka 26 127 7 8 15 2 5 00 0 73 1,1 Tanjung Sura 8 000 2t91916 I7 422 I r08 15 3 116 6197 6 58 0 53 l6 Rhu Tiga 17 4 15 33 8913 0 214 J 119 17 Kuala Abang 0 264 5121 4 13 0 29 Rantau Abang Sanctuary l8 Rantau Abang II 165 133 t34 161 t44 80 15 54 76 4 41 19 r 086 19 Government Reserve 65 rl 22 4t t] 0 l0 9 3 1 4 r 190 20 Rantau Abang I 400 200 345 183 86 r03 67 t3 33 12 38 5 154s Northern Beaches 2l Jambu Bongkok 44 ll l6 16 l0 24 11 4 4 I 3 0 t44 22 Rantau 122 6 l3 r 13 35 5 12467 23 Pulau Kerengga 123 2 4 24 20 3 00032 24 Tanjung Kanan 02 0 0 00 00 0 0002 25 Kuala Bharu 00 0 0 0l 00 I 0103 26 Mengabang Sekeping 00 0 0 0l 00 2 0104 27 Telaga Papan 00 0 I 00 00 4 000s

Grand Total 788 41 8 596 502 361 286 280 201 23t 58 213 37 3983

Tur"tle Sanctuary 630 350 501 385 247 183 t52 I 36 tt2 t7 83 25 2821 Vc C,ontribution 80 84 84 77 67 64 54 66 48 29 39 68 7I

North of Sanctuary 68 18 24 34 13 43 t69 19 2 7 4 257 Vo Contribution 944 7 4 15 64 8 3 3 ]t 6

South of Sanctuary 90 50 tl 83 t07 60 trz 62 100 39 t23 8 905 7o Corltribution I I 12 t2 17 29 2I 40 30 43 67 58 22 23 remain extremely popular for turtle watching among foreign Malaysia, as consumption of turtle meat is prohibited in and local tourists. This is clearly attributable to their easy Islam. In neighboring countries, however, leatherback turtles accessibility, with the main road running parallel to the are reported to be more frequently hunted and in greater nesting beaches. Tourist arrivals have no doubt generated numbers now because of loss of traditional sources of substantial income for the local inhabitants, but they have also protein through deforestation. Suarez and Starbird (1995, created immense problems for the turtles which, by nature, 1996) estimated that approximately 200 leatherbacks are seek dark, quiet, and undisturbed beaches for nesting. killed per year in traditional fisheries in Maluku, Indonesia. The core nesting atea., designated the Government Re- There is no evidence as of now that the Malaysian leatherbacks serve, has been developed for tourism and for many years, are impacted in this take, but research using flipper tagging the nesting turtles were left vulnerable to the uncontrolled or genetic techniques may reveal some answers. and unsupervised activities of large crowds of ill-informed Marine Pollution and Non-Degradable Marine tourists and their guides. In spite of the enforcement of the Debris The South China Sea is polluted with tar and Turtles Enactment 195 1 (Amendment) 1987 ,tourism and its dissolved hydrocarbons (Law and Rahimi, 1986; Liew and related activities remain a significant disturbance factor in Chan, 1994). The effects of oil pollution and fatalities the sanctuary. Because of this, the turtles appear to have caused by the ingestion of tar by young turtles has been well shifted south along the coast to nest (see section above on documented (see sources cited in Chan and Liew, 1988). "Spatial Trends"). However, this emigration will be short Entanglement in discarded fishing gear and marine debris, lived as the southern beaches are also being developed for toxicology, and ingestion of plastics and other debris have industry, tourism, and housing. been reviewed in National Research Council (1990). These Direct Hunting of Leatherbacks in Neighboring effects have not been assessed in Malaysia, but must Countries. Leatherbacks are not directly hunted in undoubtedly impact the leatherbacks of Terengganu. CunN aNn Lrew - Leatherbacks in Terengganu Ir_r i

Table 2. Leatherback hatchery data fiom l96l to 1995. (Soulce: Fishelies Department ofTerengganu, Malaysia).

Year No. of Eggs % of Total No. of Hatchlings Hatch 3-Year Average

Incubated Eggs Deposited Ernerged/Released Rate (7r) Hatch Rate (% r

t96l 8,366 3,699 44.2 1962 | | ,654 6,300 54.1 l 963 9,956 5,5 80 56.1 1964 I 1,535 3,903 33.0 47 .7 1965 10,67 L 7 ,199 7t.5 1966 3 I ,250 16,477 52.7 1967 I 5,650 9,215 5 8.9 6r.0 r 968 40,000 I 8,33 I 45.8 1969 3 8,009 9.5 15,,930 53. r t970 3 1,050 l7,0gg 55.0 5l .3 t97 t 47 ,39 | 30.260 63. l 1972 60,000 37 ,193 62.0 197 3 72,,260 30,699 ,12.5 55.5 t9t 4 9l .l47 1 304 42.616 46.8 t97 5 85922 40,565 4t .2 J 197 6 69,480 44,490 61.0 52,7 1977 7,803 4.57 8 5 8.7 t978 34.391 16 3 14,879 13.3 1979 24.739 l I I ,509 46.5 +9.5 r 980 29,381 l0,l l8 34.4 198 l 24,7 13 9,526 3 8.6 1982 41,812 1 3s2 20.116 .18.3 -+0.+ 1 983 11,119 5,335 47 .6 t984 14,563 J 6929 47.6 r 985 1 6.1 00 44.7 7,245 .15.0 167 1 986 25,794 53.5 12,823 49.7 1987 30,21 I 72.0 14,01 I 46.4 r 988 26.254 8s.3 9,420 35.2 '13.8 r 989 28,321 r00.0 9,17 6 34.s r 990 20,560 86.4 8,028 39.0 1991 17 ,210 98.3 4,,304 2s.0 3 2.8 1992 18,149 91.2 6,797 37 .5 t993 4,896 9t.9 1.135 23.2 t994 18,177 r00.0 8,499 46.8 3s.8 1995 2,929 100.0 632 21 .6

Total 1,03 | ,531 495 .154

LEATHERBACK CONSERVATION ies Department of Malaysia) convened a National \\'pr.'- - IN MALAYSIA shop on Sea Turtle Conservation and Management in 1 9 S The State Legislature of Terengganu also adopted the Turtle , Conservation efforts on the Malaysian leatherback Enactment, 195 I (Amendment) 1987 to provide tor rno:: started in 196l when the Malayan Nature Society first stringent measures for the protection and management oi:e; proposed the establishment of a hatchery in Rantau Abang turtles in the state. (Wyatt-Smith, 1960). Hatchery operation remained the sole Through the provisions of the Amendment, the Ranr;-. conservation measure for more than 25 years. This has proved Abang Turtle Sanctuary and the Turtle Sanctuary Adr i:rrr.. to be ineffective in sustaining the population (see above) as Council were established in 1988. The council sene . . evidenced by the population crash highlighted by Brahim et al. advise the state government on matters pertainin.r rc-r rh; (1987), Chan (1987a, l98lb, 1991 ) and Chua (1988a). conservation and management of sea turtles in Terenggan'-. The late 1980s saw a recognition of the need to intensify The sanctuary covers 14 km of nesting beaches and \\;- conservation work on the leatherback. Through support created to curb further development within its premi:r: from a private agency, a major sea turtle research and Turtle watching regulations have been introduced to contr,: . conservation project was initiated by Universiti Kolej the activities of the tourists within the sanctuary, but the.: Terengganu (formerly Universiti Pertanian Malaysia have been ineffective due to limited enforcement personne- Terengganu) in 1985. The project launched an educational and capacity. campaign whereby brochures depicting the plight of the In view of the population crash recognrzedby the srari leatherback and the population crash were mass-produced government, the commercial sale and consumption of leath- for distribution. A turtle coloring book was also published erback eggs were le_eally banned in TerengganLr in 1985 ::. for distribution in local elementary schools (Chan, 1987 c, order that 1007o of the eggs deposited could be saved i,-: 1988; Chan and Liew, 1990b) hatching. Hatchery practices have been fine-tuned ttr c:. - Through the awareness created, the local authorities hance hatch rates. To collnteract the effects of previou: .:..- (Terengganu State Economic Planning Unit and the Fisher- female hatchling production, 4-157o of the eggs har.e b.'c.:' tt CuElollrnN CoNSERVATToN AND BtoLoGy, Volume 2, Nuntber 2 - 1996

50000 adult mortality is not reduced. The international community = has a role and responsibility in addressing the mortality of Malaysian leatherbacks in high seas fisheries. 40000 With control of fisheries and complete protection of = eggs, there is hope that the rate of decline can be arrested to tD ensure population stabilization and eventual recovery. The - recovery of the Tongaland leatherback population from about 5 nesting individuals in 1966 to over 80 in 1979 and 124 in 1995 (Mrosovsky, 1983; Hughes, 1996) shows that reversals are possible and offers some optimism for the []v. trend 1 0000 population. E Rantau Abang leatherback = Acknowledgments 0 1 1 990 1 960 1 965 1 970 1 e75 1 980 985

YEAR This paper has been extracted from the senior author's "The F'igure 5. Numbe r of leatherback hatchlin-qs released in Terengganu doctoral disseration entitled conservation-related biol- tl'om l96l -91. ogy and ecolo-ey of the leatherback turtle, Dennochelys coriaces in Rantau Abang, Terengganu, M alaysia," iucr,rbated annually in styrofoam boxes with male-producin.-e Kagoshima University, supervised by G. Kawamura and H. temperature regimes (Jabatan Perikanan Terengganu, Kawatsu. The authors are indebted to the Fisheries Depart- 199 | .1992, 1993, 1994). ment of Terengganu for making available turtle statistics To further intensify conservation efforts on the leather- through their reports to the Turtle Sanctuary Advisory Coun- back, World Wildlife Fund Malaysia launched a "Save the cil of Teren._eganu, and to ESSO Production Malaysia Inc. Sea Turtles" campaign in 1989. This campai.-gn has en- for a sea turtle grant in 1985, which has spawned a life-long hanced public awareness of the plight of the turtles and interest in sea turtles. produced several management plans for sea turtle conserva- LITERATURE CITEI) tion not only in Tereng-qanu, but for various other locations

in Malaysia as well. Besnvrel, P..' aNo Lnruvr, M. 1994. Status and management of sea turtles Two fishing regulations are in effect in Malaysia to at Turtle Island Pzut. In: Nacu, A.. Trono, R.. Palma, J.A., Tottts, D., (Eds.). First Asean on provide protection from fishing .-qear within territorial wa- and AgaS, F., Jr. Proc. Syrnposiurn-Workshop ters. The Fisheries Re.,eulations (Prohibition of Fishing Meth- Mzuine Tr"rftle Conseration, Manila, Philippines, pp. 139- 150. ods) 1985 Arnendment 1989 specifically bans the use of Bour-oN, R.H., JR., DrrrroN. P.H., nruo McDoNnl-n, D.L. 1996. Leather- back turftles (Dennochely,s corictcect) on St. Croix,, U.S. Viryin Islands: large-meshed (in excess of 25.4 cm) driftnets throughout the tifteen yeal s of conservation. Chelonian Conseryation and Biology coastal waters of Malaysia while the Fisheries (Prohibited 2(2):l4I-147. Areas) (Rantau Abang) Regulations 1991 was gazetted to BRRHlv, S.,, CHnN, E.H., eNn ReHnaeN, A.K. 1987 . An update on the provide offshore protection to leatherback turtles during the population status and conselvation of the leatherback turtle of internesting periods (Chan and Liew, 1995b). Given that Terengganu. ln: Sasekumar', A., Phang. S.M.,and Chong, E.L. (Eds.). leatherback nesting has become so diffused over the main- Towards Conseruing our Marine Heritage. Proc. Tenth Ann. Seminar,

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