On the conservation and management of marine turtles

(1)

ISSN 0254-380 X

VICE

No. 123

• . • # . *

4 v«\*

^ >"

Ml

• I K

OCTOBER 1993

w

t T S f S ^ t f t l * * * T O T TECHNICAL AND

ffcrertu: 3f«»rac^t

EXTENSION SERIES

% ^ ) < T H q j t T l t f c W c b l CENTRAL MARINE FISHERIES

wjirara w r a w RESEARCH INSTITUTE g&fxOT, ¥IRcT COCHIN, INDIA

INDIAN COUNCIL OF AGRICULTURAL RESEARCH

(2)

ON THE CONSERVATION AND M

There are five species of marine turtles occurring in a n d a r o u n d M a n d a p a m - Rameswaram; both in the Gulf of Mannar and Palk Bay regions. They are incidentally caught live in trawl net, shore-seine, drift-gill net and bottom-set gill net operations in this area. They are in great demand in the rural sector. Though, the fishermen are aware that these endangered animals are protected, often the profit motive make them to sell these turtles. Whenever, any incidence is brought to the notice of the Regional Centre of the Institute, attempts have been made to rescue and release them back to the sea as a conservation measure. Several severely injured and infected turtles have been transported to the Marine'Aquarium of the Regional Centre and

•Prepared by A. A. Jayaprakash, C. Kasinathan and N.

iGEMENT OF MARINE TURTLES*

treated with various antibiotics such a s (i) dip treatment in 10 ppm malachite green solution (ii) dip treatment in 5 ppm potassium permanganate solution and (111) application of fungicide, Tinaderm, for curing physical injuries and yellow and white fungal patches/infections. The turtles t h u s maintained in the Marine Aquarium had been a source of attraction and curiosity for hundreds of general public and students visiting the Regional Centre every year. An account of management of these marine turtles is given in this report.

A total of nine turtles, five belonging to the species Chelonia mydas (Green turtle), two Lepidochelys olivacea (Olive ridley turtle) and one each of Caretta caretta (Loggerhead turtle) and

hy, Mandapam Regional Centre of CMFRI, Mandapam Camp.

(3)

Fig. 1. Green turtle Chelonia mydas in captivity at the Regional Centre of CMFRI, Mandapam Camp.

Eretmochelys imbricata (Hawksbill turtle) were reared in a cement tank of the size 7.7x6.5x1.0 m. The sea water was changed on alternate days.

They were regularly fed on a diet of 3-4 kg of freshly killed lesser sardines available in this area almost throughout the year. They have been also found to relish flatfishes and sciaenids, but not leiognathids and catfishes. Occasionally the diet was supplemented with seaweeds such as Gracilaria edulis, G. corticata, Ulva sp., etc.

depending on their easy availability during certain seasons.

Some of the turtles like Lepidochehjs olivacea have been found to suffer from Haematoma; and have been treated and cured successfully (Ambrose etel, Indian Veterinary Journal, 6 7 (1990) : 168).

A large sized and injured specimen of Letherback

TABLE 1. Morphometric measurements (in cm) of the marine turtles"

Fig. 2. Loggerhead turtle Caretta caretta maintained under captive condition at the Regional Centre.

turtle (Dermochelys coriacea), popularly known as Eluvari of Dhoni amai was saved from the fish- ermen and brought to the Mairne Aquarium on 3 July 1988 (Rao et el, Mar. Fish. Infor. Sew., T

& E Ser., No. 95 (1990) : pp 9) b u t succumbed to injuries in a few days.

On 11 October 1990, eight turtles out of nine, reared in the Marine Aquarium have been released back to sea on the Gulf of Mannar side, due to lack of space in the aquarium. The details of the turtles released are given in Table 1. At present one specimen of Hawksbill turtle (Eretmochelys imbricata) is being maintained in the Marine Aquarium at the Mandapam Regional Centre.

The clear, unpolluted sea water which is available throughout the year and the location of

Body c h a r a c t e r s

C a r a p a c e length C a r a p a c e w i d t h Head length Head width Plastron l e n g t h Plastron w i d t h Anterior flipper l e n g t h Posterior flipper l e n g t h

No. of c l a w s i n t h e a n t e r i o r flipper No. of claws i n t h e posterior flipper Weight i n k g

Sex

1 54 4 5 .

16 8 4 3 4 0 3 2 19 1 1 2 2 F

Chelonia mydas 2

7 0 5 5 2 4 12 56 4 9 4 2 2 7 1 1 4 2 F

3 5 7 4 6 15 8 4 7 4 1 3 5 2 1 1 1 2 3 F

4 9 2 7 2 2 8 13 71 6 8 5 5 3 6 1 1 120

F 5 51 4 3 16 8 4 3 39 3 3 18 1 1 19 F

Lepidochelys 6 6 4 51 26 12 4 3 4 6 3 8 2 5 1 1 3 9 M

olivacea 7 6 2 5 4 2 5 12 4 8 4 9 3 3 2 4 1 1 4 4 F

Caretta caretta 8

79 66 3 4 19 61 6 1 4 5 34 2 2 98- F

* Carapace length and width measurements based on straight line method.

(4)

Fig. 3. Turtles reared in the aquarium at the Regional Centre.

the Research Centre on the Gulf of Mannar side made it an ideal site for maintaining a variety of marine organisms for research purpose and to

JUL 4 H

Fig. 4. Turtles released near the CMFRI Jetty, Mandapam Camp into the Gulf of Mannar.

create awareness among the public on conservation and management of endangered marine animals.

(5)

^ t -dH^ftg- 3FEJ ^rrfcPfr ^ t ^RT "ft W W Pwfad

%| «frs?f ^FT " f t ^ tfW SKI ^FT T ^ , %^ ?N afc HT fts: % ^fftq I^TT "STffiT ^ I ^JPl^H ^ t

*falf 2 ^ 1 3 % 1 0 % ^ " ^ ^<FRft t

¹

"WWT

«tfl*M

^T

?^3<t % ^fT ?Rf ^ t 3T<# ^ I ^TReiFT ft 3fjH)M "^t HfJNH CRT "ft "Rf "ft 3H&«K ^ ? ^ 3^%

"ft ^ii^ld 1^rr

•STMT

t n

arfiRifaT 7$rf ^ i j R M flft "I I ittS "tftft ^W* TTT3T 3Jk ^RT ^ ^K ^TC -5T# "ft «R?T ^TTcT f I f

tffcfT ft TR3^ft 45-50 "ft ftt *falf ftf TTCT % ¥T

"ft i\Z ^fcft t <ft 74 "ft "ftt

3TJ1H>

?falf ^ ?Tf% ^

"^^nfcf « H ^ f t % l 66-72 "ft "»ft falf ft ^Sft^ft

% * f h i ^ "ft ^K sffc "TOT 1s*^ " ^ # w ?ri ^ « n ^

"ft 3ty«M«lt ^T ^fl^T S ' f t T f t ^ f W T W I d l ^ M

"ft ^TC $<ftH 3 i ^ H % -ffar t^T "ft ^ "ft HRcfcfa

*TWT W l "fft^C "ft 3 " ^ 3TTg ^ t "HRT "^1% ^JT ftfar

W F T

3ik T^f -$\ ^ft

W«WH

"ft

TTRT

^if% ^r

^rc ^nfcr «ffrfr ?Ffti

ifr^t 3fJ%ftftt ^ft "Rl% "#& ^ T "STT "^PEffi fte:

%3JT "ft "ftfl^T ^ f t % I 5-8 "ft "ft faTf % 3fg##ft

^TTBft"¥l^% t 3fk "^M ^ ¥ f ^ f l^flfdcl '/^/Sw W f t ^ft %l ^t-^K " ^ f t "ft 3fpfrffcT go/

3#^%rr % w i 9 "ft 12 "ft ift ?R> tft farf w<r*

^ f t t [ i m

3^WT

"ft

WFT HROI^H

^ m^\ %\

GwuM %#PJ ""TT?^

*<HWH f S 0.2 % 0.3 ^ K «ftT % ^tft f l

^flft 1.5 TffTl^lf "ft^Ff 3fko.5 Tft%T*fcfr£%#Tq,

"3^=rferc '^stfe frlM ^ftft ^Tf|qi " ^ v^ \+L\<*

^WfoRcW %%J 3flS - ^ P [ ^JT ^R?Er ^ ? n % I 33%>

«H<=(«!dl 3fk 16-32°C dIHHH % "^T "^5!^ ^

P|<T1<

3fl^^R?fr -^1^1 ^3t "ft "Sift STToTft "«|ft ^Sf ^*T t% ^11^ ^ 1^#RT ¥? "ft ^ M ^ % | cjrgt ft 9

"ft 12 "ft ^ft "Start % 3(y«?fUflHt "^t "51?lft t[ I "^RT

% ¥T "ft 5W W f t M f 3PI^ 3n2> "R^ft cRf ft 3^M?T 80-90'/. 3#5f|%n % WT 30 "ft "^ "^faTf

aflr 600-800 m "m: w$ ^R^ ^ I*

• R ^ ,

H^PIWI

3f^ «f3f Pi+dcicn

^-

T N t -ft ft?:

WWH 27 "ft 31°C; %ff?f aftf^PR 5 "<ft ^ft ^T

"JTT 3rf^, <rte|U|d| 26-31*/.o,

^T

fT'^ 7.8-8.3 afk^tft

⁵

^ 3ftfwsR Q H I ^ "silcr

i

ffr2^: "qpft ^ 3 T?T "^ft "TT fflft

^W ^TT "=«(Tf|q I ^MMWH^eb anfe W t ^1% ^fft

%^t "ft 12-15 % "ftt % 3f*pJWtit ^T "TM^T ^ f t

%l Tstm % ^T "ft "5N TTS^ft M %l 1^T ft "?t

"^PC irffc WC % 3-5'/. ft> sFT "ft "^RT %ft %l

" ^ lft?r "^Sft ^1% "t 6-8 TRftHt "ft 600-800 UT TTTC TFf ^ f t f Vhil^WW ^TT5, ^ft

%liq 200 i t ""ft XTIT ^T% % «+Tl<Hlf^H ft 3ff& "ft

TT«F wt CRI

T^ift ^ i l«TlRi« ^m^ f m "ft ^frficT TF5T "ft Tjjfcf Hft|^ ^>T "*rf^T

•W3 if 3??q ^lllcl^l % -QMSfe ^Tlft "ft"ft^T

ft 3n^W7f -^fJT T^

T?1SH