Taxonomy of Lactarius Sp

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Taxonomy of Lactarius Sp

Preface

Since the industrial revolution, emission resulting from human activities has substantially increased the atmospheric concentration of greenhouse gases like Carbon Dioxide (CO2), Methane (CH4), Nitrous oxide (N2O), Perfluorocarbons (PFC), Sulfur hexafluoride (SF6), Hydrofluorocarbons (HFCs), etc. This increase enhances the greenhouse effect, resulting in additional warming of the earth's atmosphere. The main greenhouse gas water vapour will increase in response to global warming and further add to the greenhouse effect. This results in substantial change in global climate due to average rise in temperature, increases vulnerability of the environment and different ecosystems. Some gases are potentially more effective than others in changing climate, and their relative effectiveness can be estimated. Carbon dioxide and methane have been responsible for over half of the enhanced greenhouse effect in the past, and is likely to remain so in the future. Atmospheric concentrations for the long-lived gases (carbon dioxide, nitrous oxide and CFCs) adjust slowly to change in emission. Continuous emission of these gases at the present level would subject us to increased concentration for centuries ahead. The GHGs would require immediate reduction in emissions from human activities of over 60% to stabilise concentrations at today’s level: methane would require a 15 – 20% reduction.

The Scientific Evidence of Climate Change:

It has been established already by various scientific bodies through their prolonged observation that the average temperature of the earth surface is changing at a very fast rate. The Third Assessment Report of Inter-governmental Panel on Climate Change (IPCC) has clearly depicted that the global average surface temperature (the average of near surface air temperature over land, and sea surface temperature) has increased since 1861. Over the 20th century the increase has been 0.6 ± 0.2°C.The last decade has been observed as the warmest with India and South-East Asia experiencing frequent extreme climatic events.

It is thus evident that climate change is the reality and human induced greenhouse gas emission is the major contributor. The increase in temperature of the earth surface is affecting the biodiversity, putting an extra stress on already endangered flora and fauna species causing an alarming future scenario.

Climate Change & Fisheries:

Barnett, Pierce and Schnur (2001) rightly pointed out “A major component of the global climate system is the oceans; covering roughly 72 percent of the planet’s surface, they have the thermal inertia and heat capacity to help maintain and ameliorate climate variability. Although the surface temperature of the oceans has been used in detection and attribution studies, apparently no attempt has been made to use changes in temperature at depth.” At sea level, closer to the coast, the climate reflects the average seasonal thermal dynamics of the ocean’s surface and surface winds, and through push- pull of energy loads, it stabilises the environment.

The demand for marine fisheries has increased many folds as the oceans have been exploited profusely, using highly developed fishing vessels and gears. Overfishing has led to over-exploitation of some marine species, which has in turn led to a progressive

1 change in the composition of the global catch to species of lower economic value. While over fishing could be a major reason for declining in fish stocks, increase in sea temperature, decrease in freshwater flow into the sea and decrease in rainfall have had an equally adverse impact.

Regional and global climate change has previously occurred and climatic patterns, as recorded, are repetitive. Certain fisheries system reflect these variability in climate quite dramatically, as noted by Hjorth (1914, 1926) and Russel (1931, 1973). And fisheries catches provide unique ecological climate indicators, as described in recent literature.

One thing is certain, that climate will continue to change, and fisheries distributions and abundance will continue to respond as they have in the past (Soutar and Isaacs 1974; Soutar and Crill 1977; Baumgartner et al. 1989; Baumgartner, Soutar and Fereira- Bartrina 1992; Kawasaki et al. 1991). The collapse of the California sardine in the 1940- 50, the Peruvian anchoveta in the early 1970, and the Atlantic Cod in 1980s led to shift in fisheries research, with dynamic forces & processes acknowledged as crucial components for fisheries management.

Impact of climate change on regional fisheries can be ranked in terms of likelihood (for either warming or cooling) of impacts. Most of this knowledge comes from empirical studies over the recent 50 years, when weather and environmental records became fundamental to explaining individual species’ behaviours and population responses to changes in local conditions.

The fisheries most sensitive to climate change are also amongst the most affected by human interventions such as dams, diminished access to up- or down-river migrations, filling in of wetlands, and other issues of human population growth and habitat manipulation, particularly expanded agricultural water use and urbanization.

Climate events such as ENSO warm and cold events promote different levels of productivity. Over India, the El Nino is supposed to bring drought and the La Nina of rain. But it was observed in 1997, when the El Nino occurred, monsoon was normal in India. K. Krishna Kumar of the Indian Institute of Tropical Meteorology (IITM) at Pune argued in a paper published in Science, 1999 that the weakening link between ENSO and the Indian monsoon could be result of global warming.

With this background, the present study attempts to link climate change to the decline of the Lactarius fisheries, off coast Tuticorin, Tamil Nadu, India. An extensive research taking into account other fisheries in the region will help strengthen this linkage between climate change and fisheries in the South Asian waters.

Dr Swayam Prabha Das Mr. Samarat Sengupta

2 Introduction

Ever since man has started interfering with the delicate balance of nature, disregarding the replenishing capacity of individual biota, the ecological devastations and habitat degradation, extermination of several species of plants and animals have become pronounced (Bensam and Menon 1994). This is also applicable to the marine realm, because the population explosion has created a demand for the alternative supplement of animal protein from the seas. Demand for fish and fishery products both for internal consumption and export taken a quantum leap leading to extensive fishing activities. Competition in fishing and diversity of the harvest is further strengthened by higher mechanisation of fishing vessels, technology support and declaration of EEZ up to 200 miles.

Of the total 1400 species of fishes recorded from the Indian marine environment, more than 500 species are from the demersal realm where less than 200 species form regular components of the demersal fisheries. Their exploration invariably centers round the coastal waters up to a depth of 50 m or so, owing to the economic and operational limitations (Bensam and Menon, 1994). This has led to overexploitation of wild stocks, depletion in natural stock replenishment and loss of species. One such important food fish that has a demand throughout the coast is the false trevally otherwise called as White fish or big-jawed jumper (Lactarius lactarius). The people of Tamil Nadu more specifically the coastal population of Ramanathapuram, Tuticorin and Kanyakumari enjoy this fish as a delicacy only next to the seer fish and barracudas that is tasty and costly. The fishermen locally call them as KUDHIPU, SUDUMBU or KADUMBU. Although an important food fish, very little information is available on its biology and fisheries (Neelakantan and Kusuma, 1991). The sudden reduction and fluctuation in catches has incredibly elevated the cost of the variety making it as one of the posh food fish species to be purchased. Direct effect of ecological imbalances can be attributed to the white fish, otherwise called the ‘false trevally’. The study highlights the findings on the natural and anthropogenic factors that have led to the loss of the fisheries for a decade at the moment.

Objective

The main objective of the study was to undertake a survey on the effect of climate change on the fishery the false trevally (Lactarius lactarius) and the narrowing down of the income of the small – scale fishermen. This will help us to understand in detail the present status of this fishery. In addition, ecological studies for identifying the shift in breeding grounds or migratory patterns during the last 10 years will aid us in providing a baseline data for future studies.

Fishery of Interest

Much is forgotten for the past 10 years about a tasty but easily perishable small fish, the false trevally (Lactarius lactarius). They basically grow up to 40 cm dwelling in coastal shallow waters. This fish occurs in water depths of < 100 m in a wide range of habitats. But according to FAO, they dwell in sandy or muddy coastal areas, caught during night by bottom trawling. The coastal belt beginning from Rameswaram and ending at Kanyakumari on the South-East coast of India enjoyed the availability and gourmet of this species for many generations. Highest landing of this species was noted in

3 Mandapam, Pamban and Tuticorin areas from bottom trawling. During peak seasons, 6 – 8 tons per day land in the Ramnad district while up to 10 tons per day land in the Tuticorin district. Pair trawling was another important fishing method to trap Lactarius. Fishermen who have small fishing crafts use a gill net called “Erandu number valai” (2 No. net), which, actually, is a modified gill net. These small-scale fishermen (those that use small fishing crafts and gears) are forced to catch other commercially low priced fishes due to the non- availability of this trevally.

Region under Consideration

The Gulf of Mannar region extending up to Kanyakumari is the area addressed for the present study. This area is unique, possessing 21 coral islands and a wide diversity of flora and fauna. The presence of sea grass beds and macro algal forms together with the coral reefs have made the area an excellent feeding ground for fin and shellfishes. The Tuticorin region of the Gulf of Mannar forms the southern most tip of the Marine Biosphere Reserve and is one of the important fishery zones for the false trevally (Lactarius lactarius). Hence the survey was undertaken in this area to identify the loss in fishery and the shift in fish catch to other fishes.

Methodology

The survey was carried out as follows

1. Collection of fisheries data from a. Fisheries department b. Research centers

2. Gathering information through interviews with a. Villagers (Fishermen) b. Middleman c. Selected group of consumers (Urban)

3. Identification of pre-existed fishing grounds through interviews with local fishermen

4. Effectiveness of the crafts and gears used in this fishery.

5. Collection of landing data (Survey and data collection from the fisheries department)

6. Reduction in landings in the past few years (data collected from fishermen and the fisheries department).

4 Profile of the Study Area

The study area in the Tuticorin coast covers a coastal stretch of 60 kms from Vembar to Punnakayal. There are 4 important landing centers from the north namely Vembar, Tharuvaikulam, Tuticorin and Punnakayal (Fig. 1). In between this, there are 8 small fishing villages namely Periyasamypuram, Keezhavaipar, Pattinamarudur, Vellapatti, Tuticorin north and south (inclusive of Siluvaipatti, Thalamuthu nagar, Thirespuram and Inico nagar), Ratchanyapuram and Pazhayakayal. The total population and social status of the villages are given separately in the following tables as per the Tamil Nadu Fisher folk population census of 2000 (Annexure 1 - 12).

Though there are 12 fishing villages in the study area, emphasis is on the 4 villages mainly because of the gears and crafts that they use for the Lactarius fishery. In case of Vembar and Thirespuram, bottom trawlers are used for trapping the false trevally whereas in Punnakayal, fishing is with drift and gill nets, more specifically to sardine fishery. In case of Tharuvaikulam village, the gears used are modified gill nets which land a good quantity of shoaling and pelagic fast swimming fishes. Majority of the catch of false trevally comes form the bottom trawlers compared to drift and modified gill nets. The fishing depends on season and fishing grounds for this particular species. The target villages of Vembar, Tharuviakulam, Tuticorin north and south and Punnakayal are shaded in dark colour.

Map showing study area

5 Taxonomy of the false trevally Lactarius sp.

Lactarius lactarius (Bloch and Schneider, 1801)

Class: Actinopterygii; Genus: Lactarius; FAO names: False trevally Common name: Big jawed jumper, white fish Vernacular names: Sudumbu, Kudhipu and Kadumbu.

Distribution of the species

Indo-west pacific: East Africa and eastern Indian ocean extending eastward to Southeast Asia, north to Japan, south to Queensland, Australia.

Dwelling environment

They are found to inhabit and dwell in pelagic realm of the oceans and sometimes are found within the estuarine areas (brackish water zones). They are seasonal in occurrence on mud banks but have not been found of any other substratum out of season. They thrive well near the reef outer areas and are seen in shoals migrating to the surface water. They are found in depths ranging from 15-90 m. They are also encountered only on a substratum of mud, or mud and sand in daytime trawling operations. Apparently at night they leave the bottom to the mid water zone.

Commercial importance

This fishery is of great commercial value to countries like India, Pakistan, Bangladesh and Myanmar. In India, it ranks one of the most preferred, quality food fish. The states of Tamil Nadu and Kerala have a comparatively larger number of consumers to other maritime states in the country. It is sold fresh or dried. The decomposition rate of this fish is high.

6 Resilience of the species

Resilience is high for the species and the doubling of the population is within a time period of less than 15 months. Research on the species biology from the coasts of Karwar off Karnataka water has been conducted but extensive studies is yet to be concluded.

Diagnosis

8-9 dorsal spines, 20-22 dorsal soft rays, 3+3 anal spines and 25-28 anal soft rays. On the dorsal side of the body there is a silvery gray color with blue iridescence while the ventral side is silvery white. Upper part of gill cover has a dusky black spot with pale yellow fins. Mouth is large and oblique.

The lower end of the interspinous bone is broad, fan-like with one side affording articulation with the first and second anal spines. This is a unique feature and of taxonomical importance to L. lactarius, the single representative of the family Lactaridae (Alam et al. 1989).

IUCN Status

Not in the IUCN red list.

Background Fishery Status

As per the landing data available for the false trevally from CMFRI (Central Marine Fisheries Research Institute), there has been drastic reduction in catches in the Tamil Nadu coast. In Tuticorin, the fishermen understand that the fishery is now on the verge of dissipating. They also pointed out that the fishery has now shifted towards the Thalaimannar area of Sri Lanka. A few now and then catches are also recorded from Yeruvadi area fished by the fishermen of Keelakarai and Yeruvadi. Down south, the catch is available in moderate levels at Kanyakumari coast.

7 Landing data of Lactarius in Tamil Nadu

2000 1800 18 2 2 s

n 1600 o t 1400 13 4 8 13 7 3 n i 1200 s 10 2 8 g 1000 9 7 7

n 9 3 8 i 8 2 3 8 4 0 d 7 7 5 800 7 2 2 7 4 0 7 14 n 6 4 0 6 7 9 6 3 3 a 6 11 l 600 5 3 7 5 3 7 4 7 0 400 3 2 9 3 7 2 2 3 4 200 2 0 1 17 5 0 years from 1969 - 1993

The above figure gives the detailed picture of the landings of this fish with a peak landing of 1822 tons during 1973 that has come down to 175 tons during 1993-1994. The landing data is not available for the past 10 years for this fish in case of the Tamil Nadu coast.

The fishermen of the Tuticorin coast are still discussing the possible reasons for stock depletion. Earlier the fish catch was within 5 miles from the shore during 1980’s but today only a few kilograms of the fish is caught even after sailing out for almost 40 to 45 nautical miles. The peak seasons were December to March every year when half to 1.5 tons of fishes were caught by a single boat. In the present scenario a meagre catch of hardly 150 kgs during the peak season is recorded, though there is a big fleet of 350 odd fishing crafts at the Tuticorin main fishing harbour area. As for the country crafts, there has been minimal or absolutely 'no' catches from the nets like No.2 and drift gill nets that were once the chief gears to catch the white fish in large numbers.

Biology and stock replenishment

A clear knowledge of the reproductive potential or fecundity of a fish is quite an essential pre-requisite for the proper management and conservation of the resources. The fish is not of a big variety and the average size is up to 30 cm. The largest so far recorded is a specimen that had a total length of 33 cm caught in a drift gill net at Pamban in the Gulf of Mannar (Shanmugavelu, 1973). In an attempt to study the biology of the fish, Neelakantan et al (1981) has identified that the sex ratio shows males outnumber females in all months except in October. The insignificant difference in the number of individuals of both the sexes during spawning months (January, March, October and November) indicate that males and females congregate especially during these

8 spawning seasons. The minimum size at maturity coincided when relative condition factor was applied to collected specimen of Lactarius lactarius and the period of maturation of gonads was expected to be during the month of February (Neelakantan et al. 1986). The ability of egg production varies within the individual limits such as length, somatic weight, gonadial weight, volume of the fish etc.

Crafts and gears utilised in Lactarius fishery

There are no specific nets for the fishery of false trevally. Trawl net catches are the maximum for these fishes followed by drift gill nets, Irupuri nets, sardine nets, shrimp nets and No.2 gill nets. Sometimes, even push nets land these fishes but in comparatively lower quantities. The main reason for the good catches in trawl nets is basically because of the speed of the fishes and the matching speed of the trawlers. Fishermen substantiate these finding based on their experiences, by stating that these fishes cannot be caught while trawling at low speed.

False trevally undergoes vertical migration and is found nearer to the surface waters - maximum during the early hours of the morning and after sunset in the evening. Therefore maximum catches can be obtained between 07 hr – 10 hr during daytime and 18 hr – 20 hr during the evening. As the whole shoal consists of fast swimming fishes, the speeds maintained by the boats are 3 – 3.5 nautical miles as compared to the normal speed of 2.8 – 2.9 nautical miles per hour. If the speed is less, the false trevally escapes through the sides of the trawl nets. The trawler boats used for fishing are 54”x 19”x 12” and 51”x18”x17” having 160 Hp and 108 Hp respectively. Similarly country crafts called “Vallam”, a traditional craft in the Tuticorin region, fishers use craft loaded with gear like drift gill nets that land the false trevally too. The size of the traditional country craft ranges from 25.5”x 7”x 4.5”, 27”x7”x 4.5”, 28.5”x 7”x 4.5” and 31.5”x7”x 4.5”feet. The engines are usually 8, 10 or 12 Hp inboard engines. The dwelling zone for the false trevally is near the silty sand areas adjacent to the reef. So in case of deeper reef, the trawl nets are operated close to the reef in such a way that the nets do not get entangled in the reef but can smoothly sail through with the catch. One particular fisherman from Tharuvaikulam village has acquired a catch of 1.2 tons in a single day near the reef area itself. Nowadays 4 fathoms is the depth zone near the outer reef for false trevally fishes whereas a decade ago, the same fishermen were able to obtain good catches at 2 fathoms depth in the coastal waters close to the mouth of estuaries.

The different net types for Lactarius lactarius

S.No. Net type Mesh size (mm) 1 Irupuri net 25, 26, 36, 40 2 Sardine net 40 3 No. 2 net 50 4 Shrimp net 15,30 5 Trawl net 10 6 Shore seine 10

9 Another problem faced by the fishermen is the misuse of marine fishing regulation. Usage of destructive nets and destructive fishing practices has caused loss of habitat for many species of fin and shell fishes. Earlier there were clear-cut laws for fishing between the mechanised and non-mechanised crafts. The traditional country crafts were regulated to fish within 8 – 15 km zone whereas, the mechanised sector were to fish beyond 50 km zone seaward. Now, all fish in the same area and continuous conflicts are arising between these two sectors. The season for fishing false trevally also seems to be during the season when 45 days fishing ban is operational.

Fishing grounds

A decade ago, the entire Tuticorin shallow coastal region had abundance of the false trevally in depths of 2 fathoms while now the fishermen have to travel long distances and fish in the deep continental region. The different paars and the depth of fishing zones are given in (Figs. 2 and 3) with the key for the paars in the region. In Vembar, the fishing season for the false trevally was during April where every boat at an average was able to bring ashore at least 10 Kgs of fish. The same period had a catch of 40 kg and more during the past one decade. Earlier the fishermen of this village were trapping false trevally in depths of 4 fathoms but in the present scenario, they are fishing at depths greater than 20 fathoms. The chief fishing zones identified in Vembar Lactarius fishery included that of the Sallipattu madai, 22 paagam madai, 6,7,8,9,10,11,12, 13 paagam madai. The depth range of the fishing zones are from 6 fathoms to 22 fathoms. The Vembar group seems to be free of rocky reef topographical area while exclusively sandy silt in nature.

In case of Tharuvaikulam village, the fishing of false trevally was carried out near the estuarine mouth close to the shore of the river Kallar. Those days, shrimp nets were used to catch the species and this was supported by “Ola valai”, a modified mini version of the shore seine. This indigenous net was operated from the shore and this clearly portrays the abundance 2 decades ago. The fishermen at peak seasons were able to trap these fishes up to 160 kgs per boat. January and February months are the fishing season in this village where each boat brought not less than 50 - 60 kgs. Presently, the catches have come to a stand still. The fishermen have to travel long distances to trap these fishes which becomes very expensive and lengthy fishing hours leading to poor catches and minimal operation of time. Appa and Nallathanni islands of the Vembar group was once a paradise for the false trevally as they were dwelling in these areas in large quantities right from a depth of 2 fathoms. Certain destructive trawl nets with less than 5 mm mesh size have resulted in the loss of habitat and destruction of the reef. This has led to the loss of Lactarius species from the island area and the fishes have now migrated to deeper water where still the topography remains undisturbed due to severe overexploitation. The main fishing grounds now that are used as fishing grounds are 20 fathoms or more in depth. Nadu madai was one of the most preferred areas having a depth of more than 20 fathoms. Other than that reef outer area of the Appa Island and adjacent reef area were preferred. The depth ranges from 20 to 35 fathoms for these fishing grounds.

Tuticorin region is the most commercially active region due to the large fleet of fishing crafts involved in trawling and associated activities. The peak fishing season is from December to March. A single boat landed 0.5 - 1 ton per day in a single catch during the late eighties. In the beginning of 1980, fishermen caught the fishes close to the shore (5 miles from land) in depth ranges of 5 - 20 fathoms. Now the same fishermen are

10 travelling a distance of 40 - 45 miles in the sea if they need a good catch of Lactarius. Even these remain as a luck factor hence, fishermen instead of going for a particular fishery like the false trevally undertake a common fish trawl that will also trap other fish species. This has avoided loss of concentrating fishing on a particular species. The Tuticorin fishermen also depended on current patterns because of the migration of the shoal near estuarine mouth region of Punnakayal zone. Now in this region, only 20 kgs are caught and never more. Fishermen in the late eighties preferred to travel long distances up to Kanyakumari in the south and up to Yeruvadi in the north for fishing of this species. Due to the fishing competition and fishing pressure, fishermen are forced to shift fishing grounds and certain fishing grounds like the Punnakayal madai has to be shared between both country crafts as well as the mechanized ones. This has often resulted in clashes and problems between neighbouring villages. The main fishing area for Tuticorin fishermen is Punnakayal madai, Yeruvadi madai and Manapadu shoals area.

Punnakayal fishermen use traditional country craft (Vallam) for the past 2 decades fishing with sardine gill net. This net is important for the trapping of false trevally in coastal waters very close to the shore. Certain fishermen are also operating the 3 logged catamarans for the fishing of shoaling fishes with an outboard engine of 8 Hp capacities. Past catches in mid seventies and eighties have recorded landings up to to 300 - 500 kgs per boat. Nowadays, hardly 1 or2 Kgs are landed and that too immediately sold out as the demand is high. The main fishing grounds followed by these fishermen include Koil madai thavu - 5.5 fathoms, Kanna madai - 4.5 fathoms, Mela thundathi pallam 8 - 12 fathoms, Pora paar - 6 fathoms, Punnakayal madai - 21 fathoms and Virudhachivi paar - 9 fathoms.

Loss of Fishery due to Climate Impact

Both nature and man has played a key role in the sudden decrease in the natural population of the false trevally Lactarius lactarius. Rainwater plays the most important role in the productivity of the coastal environment. Rainwater flushes all the nutrients of lithogenous origin entering into the hydrogenous system of rivers. The river water finally finds the sea forming estuarine complex near the mouth region. The estuarine areas thus provide ideal shelter and required food for all larvae, juveniles, fry and fingerlings of fin and shell fishes.

The entire Tuticorin coastal region has not received any proper rainfall for the past 6 years. Out of the 2 major rivers, Thamiraparani that meets the sea near Punnakayal is the only one that flows throughout the year while river Vaipar has totally dried up. The two small rivers namely Kallar and Vembar have also dried up as check dams and reservoirs are built all along the way. Lack of rains is the chief reason quoted by many of the fishermen, fisheries department personnel and fishery biologists for the loss of Lactarius fishery. This is evident from the rainfall data available from the meteorological department (given below). Similarly, there is a reduction in the associated parameters like temperature and in pressure for the region under consideration. Lack of supply of food in the coastal waters has led the species to move into deeper waters which is supported by continuous, unsustainable and repeated fishing in the same area.

A gradual decrease in rainfall is noticed right from the effect of El-Nino during the period of 1997 and 1998. Rainfall is poor from this effect onwards till the data that is available for 2003.

11 Average mean temperature

29.8 n i

e 29.6 r s u u t i 29.4 a c r l e e 29.2 p C

m 29 e

T 28.8 1994 1996 1998 2000 2002 2004 Years

Mean average pressure n i 2000 e r u s s 1500 r s a e b r 1000 i p l

l i e g m 500 a r e

v 0 A 1994 1996 1998 2000 2002 2004 years

Rainfall data

1200

m 1000 m 800 n i l

l 600 a f 400 n i a 200 R 0 1994 1996 1998 2000 2002 2004 Years

12 As for the pressure, it has been steady even during the El Nino periods but is slightly in the increase right from 2002 onwards. Thereby, El Nino has caused a change in the climatic pattern by an increase in the temperature and at the same time a decrease in rainfall. Surprisingly, the pressure and the shortage of rains is found to be increase in the years 2002.

The actual habitat of the false trevally Lactarius lactarius is silty soil that is found near estuarine region (silty clay) and in the outer reef areas. Since there is reduction in production of the costal waters coupled with the industrial development in this part of the country, these fishes have shifted their breeding grounds to deeper waters. Lactarius lactaius are now thriving outside the reef area in deeper waters (Figs 4 and 5). No work on the biology or stock assessment of this species is available for this particular species in this particular region of the country. Research on the stock replenishment pattern and biology of this species needs to be conducted soon to sustain this species over a period of time.

The climatic factor is supported by the destructive fishing practices that were carried out throughout the region till date. This illegal fishing method involves the usage of gelatin or amatol sticks as explosives for fishing called dynamite fishing. The usage of explosives is very severe as they can destroy a reef in less than a few seconds in to rubble. This has left a permanent loss if habitat for the dependent fish or shell fish forcing it to either migrates from its lost area or to die in the same area. Trawling with small mesh sizes of less than 2 mm are also banned but were well practiced a few years ago in Tuticorin region.

This “El - Nino” phenomenon that took place during 1998 brought a sudden loss of this fish variety in this region. Surprisingly, the fishes are now spotted at Ovari and Kootampuli regions of Kanyakumari district and Yeruvadi in Ramanathapuram district. These are indications that a possible “La - Nina” phenomenon that occurs a few years after El - Nino could be one of the reasons. Still the fishery seems to have lost its glow as it was 2 decades ago. This is strongly supported by Venkataraman (2000) who have remarked about the unprecedented bleaching of hard and soft corals throughout the coral reefs regions of the world including the Gulf of Mannar Marine Biosphere reserve India, from mid 1997 to late 1998 due to a large El - Nino effect followed by a strong La- Nina. Coral Reefs are the best biological indicators, because of the sensitivity for recording rise in temperature and hence the best way to identify any changes in the marine environment. The effect of climate change with reduced rainfall, coupled with destructive fishing practices has drastically brought down the Lactarius fishery. The economic value of the fisheries has also drastically increased from Rs 5 per kg to Rs 80- 100 per kg, mostly due to the preferences of the coastal people to this delicacy.

The Socio-economic Indices of Dependent Fishermen

A decade ago, the fishermen of the Gulf of Mannar used to bring home 35 - 60 Kgs/ day of Lactarius during peak seasons (Rs. 80 - 100/ Kg) while 7 -12 Kgs/ day was caught during the lean seasons. Fishing took place throughout the year and on an average, a single fisher folk household was able to generate an income of Rs. 600 - 700 per day. Whereas, the trawl owners, earned up to Rs. 1000 – 1500 per day.

13 Price indicator for Lactarius sp. fish for the last 8 years

Year Price (in Rs) 1996 80-100 1997 80-100 1998 80-100 1999 80-100 2000 100 2001 100 2002 100 2003 120 The catch had a supportive market, especially in the neighbouring state of Kerala where it fetched better prices, offered by auctioneers and buyers. Record haul of 3 - 5 tons per day was witnessed during early eighties. This brought excellent returns to the fishermen in terms of market. Now, the drastic reduction in the fish stock has resulted in fishermen using a single fishing ground continuously that also lead to the slow decline of other species dwelling in that area. Because the boats travel longer distances but bring back poor catches, economic loss is inevitable.

Earlier, fishermen could earn a minimum of Rs. 100 - 200 per day for Lactarius, along with other catches. In the present state of affairs, they depend on other catches because of the loss of this fishery in coastal waters. As a fall out of the above, dependence on species like Lethrinids and snappers (< Rs. 40/ Kg) has increased. This has further lead to a slow decline in the fishermen's overall income by 50 %, forcing many of them to take up alternate fishing gears like “Mayavalai” and “Mural valai” (both modified gill nets). These two nets are suitable to catch half beaks, full beaks, belonids and snappers. In such circumstances, the low economic returns on these fisheries do not deter them.

14 Conclusion:

Human activities involving use of destructive fishing practices and regular flaunting of fishing regulations have impacted the Lactarius fisheries in the region. Coupled with El- Nino effect this particular fisheries has recorded changes both in the quantum of catch and area of availability.

As evident from meteorological data, decrease in rainfall & increase in sea surface temperature from 1998-99, the catch has reported decreased. Therefore, in order to survive the climate dynamics, the species has to be mobile i.e. migrate, and be adaptive to changes in habitats.

Decline in catches and shift in their habitat is also co-related to warming of seawater temperature and reduction in the flow of freshwater into the sea. Vertical & horizontal migration recorded during this study emphasises the need to protect this commercially important species from the extensive trawling activities in the Tuticorin region.

Global environmental issues needing attention are those of controlling human growth and development, while monitoring, assessing and maintaining critical habitat. Monitoring the changes in “condition indicators”, distributions, and abundance of a particularly responsive species will help provide the necessary information to initiate effective fisheries management and enable reduction of human activities that affect “ecosystem”, thereby, ensuring long term sustainability of marine living resources.

15 References:

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2. Bensam, P and M. G. Menon. 1994. The endangered, vulnerable and rare demersal marine finfishes of India. In: Threatened finfishes of India. Proceedings of the National seminar on endangered fishes of India. (Dehadrai, P. V, P. Das and S. R. Varma Eds) – Nature Conservators pp: 297 – 305.

3. Bianchi, G. 1985. Field guide to the commercial marine and brackish water species of Pakistan. FAO identification sheets for fishery purposes.

4. De Bruin, G, B.C. Russell and A. Bogusch. 1994. The marine fishery resources of Sri Lanka. FAO Species identification guide for fishery fishes, FAO, Rome.

5. Marine Fisheries Information Service. 1960 – 2004.

6. Neelakantan, B and N. Kusuma. 1991. Exploitation of false trevally resources in Uttara Kannada waters, Journal of Marine Biological Association of India. Vol. 33(1&2): 26 – 32.

7. Neelakantan, B, M. S. Kusuma and M. V. Pai. 1981. Sex ratio of false trevally Lactarius lactarius (Bloch and Schneider). Journal of Indian Fisheries Association. Vol.10 – 11: 17 – 20.

8. Neelakantan, B, M. S. Kusuma and M. V. Pai. 1986. The fecundity of false trevally Lactarius lactarius (Bloch and Schneider) along the Karwar coast. Fishery Technology. Vol.23 (2): 174 – 177.

9. Shanmugavelu, C. R. 1973. On the largets specimen of big-jawed jumper Lactarius lactarius (Schneider). Indian Journal of Fisheries. Vol. 20(1): 244 – 245.

10. Sundaramoorthy, P.S. 1966. On a survey of the pearl banks of Tuticorin, Gulf of Mannar in 1961-1962. Madras of Journal of Fisheries, Vol.2: 71 – 77.

11. Tamil Nadu Department of Fisheries. 2000. Tamil Nadu Marine Fisher Folk Census.

12. Venkataraman, K. 2000. Status survey of The Gulf of Mannar corral reefs following the 1998 bleaching event, with implication for reserve management. Proceedings of the 9th International Coral Reef Symposium, Bali, Indonesia. 23 - 27 October, 2002, Vol.2: 855-859.

16 Key to the important fishing paar zones (reef area) where Lactarius where found a decade ago

VI Inner Vembar group 12. Uppu tanni tivu paar 13. Vembar karai paar 14. Kumulam paar

VII Outer Vembar group 15. Vembar periya paar VIII Outer Vaipar group 16. Vaipar periya paar IX Inner Vaipar group 17. Devi paar 18. Pernandu paar 19. Paduthamarikan paar 20. Paduthamarikan thundu paar

X Cruxian group 21. Cruxian paar 22. Tuticorin kuda paar 23. Cruxian thundu paar 24. Vantivu arupagam paar

XI Utti paar group 25. Nagarai paar 26. Utti paar 27. Petha paar 28. Uduruvi paar 29. Kilathi paar 30. Athuvai arupagam paar 31. Patharai paar

XII Pasi paar group 32. Attonbotu paar 33. Pasi paar

XII Tholayiram paar group 34. Tholayiram paar 35. Koothadiyar paar

XIV Kanna tivu group 36. Thundu paar 37. Kanna tivu arupagam paar

XV Pulippoondu group 38. Vada onbotu paar 39. Saith onbotu paar 40. Pulipoondu paar 41. Kanna pulipoondu paar 42. Aluva paar

XVI Nenchurichan group 43. Parkudanjan paar 44. Nenchurichan paar 45. Mela onbotu paar 46. Vadaolipathu paar

XVII Inner Kudamutti group 47. Punnakayal sultan paar 48. Sandamaram piditha paar 49. Rajavukku sippi soditha paar

17 50. Kudamutti paar 51. Saith Kudumattui paar 52. Pudu paar

XVIII Outer Kudamutti group 53. Nillankallu paar 54. Sankuraiya pathu paar 55. Sattukuraiya pathu paar

XIX Kadiyan group 56. Kadiyan paar 57. Kanawa paar.

Sources for the maps used

1. The district map of Tuticorin: DRDA, Tuticorin district.

2. Paars of the study area: Issac Rajendran et al., Fisheries department. Survey on the pearl banks of the Gulf of Mannar.

3. Depth topography map: AD Fisheries, Research Section, State Fisheries Department, Tuticorin.

4. Lactarius fishing grounds, past and present: Sambandamoorthy, P.S. 1996. On a survey of the pearl banks of Tuticorin, GOM in 1961-62. Madras Journal of Fisheries. Vol.II. 71-

18 Details of Fishermen Population and other social aspect as per survey – Year 2000 for Tuticorin region

19 20 21 22 23 Details of Fishermen Population and other social aspect as per survey – Year 2000 for Tuticorin region

Annexure. 1. Population of the target villages

Sl.No Name of the village Male Female Total 1 Vembar 1008 954 1962 2 Periyasamypuram 438 388 826 3 Keezhavaippar 747 722 1469 4 Sippikulam 338 323 661 5 Pattinamaruthur 152 142 294 6 Tharuvaikulam 2010 919 3929 7 Vellapatti 482 484 966 8 Tuticorin North 9815 9553 19368 9 Tuticorin South 6920 6211 13131 10 Ratchanyapuram 327 302 630 11 Pazhayakayal 414 429 843 12 Punnakayal 3725 3318 7043 Total272662374551011 Annexure. 2. Religion of the target villages

Name of the Religion Sl.No village Hindu Christian Muslim Others Total 1 Vembar 515 1447 0 0 1962 2 Periyasamypuram 37 789 0 0 826 3 Keezhavaippar 54 1415 0 0 1469 4 Sippikulam 6 649 6 0 661 5 Pattinamaruthur 115 0 179 0 294 6 Tharuvaikulam 555 3362 10 0 3929 7 Vellapatti 102 864 0 0 966 8 Tuticorin North 4158 13938 1272 0 19368 9 Tuticorin South 437 12689 5 0 13131 10 Ratchanyapuram 25 605 0 0 630 11 Pazhayakayal 23 820 0 0 843 12 Punnakayal 15 7028 0 0 7043

24 Annexure. 3. Community of the target villages

Community Sl.No Name of the village Most Forward Backward S.C S.T Total Backward 1 Vembar 0 1226 670 66 0 1962 2 Periyasamypuram 0 788 0 38 0 826 3 Keezhavaippar 0 0 1415 54 0 1469 4 Sippikulam 0 11 650 0 0 661 5 Pattinamaruthur 0 586 0 8 0 294 6 Tharuvaikulam 0 3489 0 440 0 3929 7 Vellapatti 0 0 966 0 0 966 8 Tuticorin North 65 3967 13935 1391 10 19368 9 Tuticorin South 0 19 13112 0 0 13131 10 Ratchanyapuram 0 20 573 35 0 630 11 Pazhayakayal 0 128 706 9 0 843 12 Punnakayal 0 0 7028 15 0 7043

Annexure. 4. Housing status the target villages

Name of the Free SI No Terraced Tiled Thatched Total village house 1 Vembar 42 120 124 76 362 2 Periyasamypuram 13 94 45 0 152 3 Keezhavaippar 36 121 14 97 268 4 Sippikulam 20 56 13 31 120 5 Pattinamaruthur 6 30 23 0 59 6 Tharuvaikulam 99 281 235 172 787 7 Vellapatti 17 87 34 62 200 8 Tuticorin North 1446 1184 1293 284 4207 9 Tuticorin South 1483 960 494 0 2937 10 Ratchanyapuram 11 54 14 49 126 11 Pazhayakayal 63 70 30 21 184 12 Punnakayal 509 403 338 200 1450

25 Annexure. 5. Housing facilities of the target villages

SI. No Name of the village Owned Rented Total 1 Vembar 317 45 362 2 Periyasamypuram 137 15 152 3 Keezhavaippar 239 29 268 4 Sippikulam 94 26 120 5 Pattinamaruthur 48 11 59 6 Tharuvaikulam 538 249 787 7 Vellapatti 158 42 200 8 Tuticorin North 2469 1738 4207 9 Tuticorin South 1744 1193 2937 10 Ratchanyapuram 90 36 126 11 Pazhayakayal 116 68 184 12 Punnakayal 1011 439 1450

Annexure. 6. Family size and status of the target villages

Name of the Total Family Persons Sl.No Families Village Population size per house 1 Vembar 362 1962 5.42 5.42 2 Periyasamypuram 152 826 5.43 5.43 3 Keezhavaippar 268 1469 5.48 5.48 4 Sippikulam 120 661 5.51 5.51 5 Pattinamaruthur 59 294 4.98 4.98 6 Tharuvaikulam 787 3929 4.99 4.99 7 Vellapatti 200 966 4.83 4.83 8 Tuticorin North 4207 19368 4.60 4.60 9 Tuticorin South 2937 13131 4.47 4.47 10 Ratchanyapuram 126 630 5.00 5.00 11 Pazhayakayal 184 843 4.58 4.58 12 Punnakayal 1560 7043 4.51 4.86

26 Annexure. 7. Educational Status of the target villages . y s l c r e l e a o t s a o S e a e m . l c r i t h r g i r a e a c e t Sl. Name of the n t H r l P i l s l l l o h

e

o t o

No Village o c l T h i o l e a o C g l t i h I T h o c H c T S s 1 Vembar 1272 147 54 31 4 1508 213 2 Periyasamypuram 673 13 11 0 0 697 32 3 Keezhavaippar 743 437 49 8 7 1244 77 4 Sippikulam 302 232 34 7 3 578 10 5 Pattinamaruthur 85 60 2 0 0 147 113 6 Tharuvaikulam 1443 947 95 32 11 2528 876 7 Vellapatti 360 169 4 8 1 542 284 8 Tuticorin North 7739 3249 689 472 166 12315 4649 9 Tuticorin South 5572 3305 945 724 276 10822 1210 10 Ratchanyapuram 424 71 22 12 17 546 10 11 Pazhayakayal 432 156 54 32 36 710 32 12 Punnakayal 2702 1369 142 63 216 4392 1782

Annexure. 8. Fishery occupation - Men in target villages h e s g s e d i i n f a t

i Employed in

i r t t g h v e g i n s t k h n i i r e c s h e s r i v

Name of the village a a t t r Sl. i f s

F

i v a e m D d e d F v o

No h t i e d e t i r i G e l a l r O P r N A D T 1 Vembar 455 0 0 0 0 0 21 80 75 2 Periyasamypuram 201 0 0 0 0 0 0 17 19 3 Keezhavaippar 408 10 1 0 0 0 2 1 14 4 Sippikulam 194 0 0 0 0 0 0 0 4 5 Pattinamaruthur 81 0 0 0 0 0 0 0 0 6 Tharuvaikulam 1114 0 0 0 0 7 3 0 0 7 Vellapatti 278 0 0 0 0 2 0 0 0 8 Tuticorin North 4012 52 30 2 289 44 80 139 235 9 Tuticorin South 1822 27 9 35 0 41 242 230 732 10 Ratchanyapuram 181 0 2 0 0 0 4 6 6 11 Pazhayakayal 180 0 2 0 0 4 6 51 4 12 Punnakayal 1706 129 0 9 1 32 29 50 206

27 Annexure. 9. Employment status of fisherwomen of the target villages h h d s s e i g i

i Employed in f l f

l n

i g h g d A k n s e n i s a e s Sl. i i . l e t h e t r r v

Name of the village r i a m a i s v e t t

No D i F i v t o h D o i e e F v t e r i T d G d t O N P a a c r r a t t 1 Vembar 0 0 0 347 0 0 0 0 31 378 2 Periyasamypuram 0 4 0 0 0 0 0 0 3 7 3 Keezhavaippar 0 6 31 225 0 0 5 0 14 281 4 Sippikulam 0 10 12 122 0 0 1 1 4 150 5 Pattinamaruthur 0 0 0 0 0 0 0 0 0 0 6 Tharuvaikulam 0 49 97 2 0 0 0 0 0 148 7 Vellapatti 0 75 43 0 0 0 0 0 0 118 8 Tuticorin North 0 37 132 14 0 2 16 15 7 223 9 Tuticorin South 0 22 6 21 0 8 22 12 55 146 10 Ratchanyapuram 0 0 12 0 0 0 2 8 4 26 11 Pazhayakayal 0 0 7 0 0 0 2 36 1 46 12 Punnakayal 0 20 30 0 0 0 3 8 40 101

Annexure. 10. Income status of fisher folk in the target villages n 0 0 a 0 0 0 0 h 0 0 t 0 0

0 5 0 5 s 2 1 6 1 l . s 1 - - a - s e 1 1 Sl. t 0 L 0 Name of the village 0 R o 0 0 0 No 0 T 0 e 0 3 2 . 6 v 0 . 1 s . o 3 s . s b R R s R A R 1 Vembar 236 375 357 37 4 1009 2 Periyasamypuram 23 31 183 7 0 244 3 Keezhavaippar 215 212 257 20 13 717 4 Sippikulam 116 63 123 45 1 348 5 Pattinamaruthur 0 64 11 6 0 81 6 Tharuvaikulam 154 148 885 63 22 1272 7 Vellapatti 119 175 103 1 0 398 8 Tuticorin North 1943 1862 974 215 112 5106 9 Tuticorin South 42 211 764 1249 1018 3284 10 Ratchanyapuram 13 200 6 1 5 225 11 Pazhayakayal 58 178 11 7 39 293 12 Punnakayal 82 157 495 975 554 2263

28 Annexure. 11. Fishing gears operated in the target villages e e t n e t i n e i n s l e e i n r e l p

a s

N l e t

s a

g l r h

Sl.No Name of the village e o w t l t r i n T a T a o r o O G o h T L B S

1 Vembar 1867 60 54 0 130 0 235 2346 2 Periyasamypuram 91 0 1 0 0 0 55 147 3 Keezhavaippar 2141 0 0 0 67 0 69 2277 4 Sippikulam 1140 0 0 0 0 0 70 1210 5 Pattinamaruthur 81 0 0 0 0 0 0 81 6 Tharuvaikulam 2730 32 0 0 3 0 32 2797 7 Vellapatti 889 0 0 0 0 0 0 889 8 Tuticorin North 287 292 18 2 39 0 3 641 9 Tuticorin South 1825 212 15 0 0 0 0 2052 10 Ratchanyapuram 384 0 0 0 0 0 0 384 11 Pazhayakayal 328 0 0 0 0 0 0 328 12 Punnakayal 3108 0 0 0 7200 0 0 10308

29 Annexure. 12. Fishing crafts utilized in the target villages

Mechanised Boats Non Mechanised Boats

e Make Type Make Type Engine g a l l i e V

o n r e n d a e r n n

Sl. r a h a t o l l l l e r e e t t m a l

o C e a a M P P e u d d f e E a

No t t l e w m t s n B R R l o o w o n t B o - o i

a I a u a l F F o o a r O S T T L y e l o t l i V M T W W a g m P G u a C D N

1 Vembar 15 20 0 15 20 0 35 41 0 0 0 41 0 0 41 41 0 2 Periyasamypuram 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 3 Keezhavaippar 0 0 0 0 0 0 0 54 0 0 0 54 0 0 54 54 0 4 Sippikulam 0 0 0 0 0 0 0 43 0 0 0 43 0 0 43 43 0 5 Pattinamaruthur 0 0 0 0 0 0 0 11 0 0 0 11 0 0 11 4 0 6 Tharuvaikulam 11 25 0 11 25 0 36 182 0 0 0 182 0 0 182 180 0 7 Vellapatti 0 0 0 0 0 0 0 49 0 0 0 49 0 0 49 47 0 8 Tuticorin North 124 8 0 124 7 1 132 116 2 1 0 119 0 0 119 117 2 9 Tuticorin South 116 0 0 116 0 0 116 121 0 0 0 56 0 65 121 46 52 10 Ratchanyapuram 0 0 0 0 0 0 0 31 0 0 0 5 0 26 31 5 0 11 Pazhayakayal 0 0 0 0 0 0 0 25 0 0 0 2 0 23 25 2 0 12 Punnakayal 0 0 0 0 0 0 0 264 20 4 0 259 0 29 288 236 23

30 Annexure.13. Rainfall data for the last eight years

1996 1997 1998 1999 2000 2001 2002 2003 January 35.6 - 5.5 19.8 28.7 1.8 3 1.1 February 7.4 - 0.3 96.1 153.5 46.4 35.4 74.3 March 0.6 31.2 -- 8.6 69.7 1.9 4.4 32.5 April 83.8 20.1 68.1 3.1 5.6 85.4 6.2 76.5 May 22.8 37.9 54.7 0.8 - 16.1 69.5 1 June 12.0 - 3.2 0.4 13.4 3.8 -- 3.6 July 0.47 8.1 31.9 1 - 3.2 10.8 1.5 August 6.5 - -- 60 5.1 -- -- 1.2 September 49.3 23.1 19.4 -- 7.7 2.8 42.2 -- October 144 243.7 36.3 180.2 9.6 82.4 111.5 24.9 November 73 352.1 202.8 28.9 147.7 68.7 135.8 175.3 December 48.7 394.9 256.1 35.7 207.8 55.4 12.5 0.4

Annexure.14. Temperature data (in Celcius) for the last eight years

1996 1997 1998 1999 2000 2001 2002 2003 January 26.7 27 27.5 26 27.3 27.3 27.4 26.9 February 27.5 27.5 28.6 27.6 28.2 27.5 27.2 28.1 March 28.9 29.1 29.8 28.8 29.1 29.2 29.2 29.2 April 30.1 30.1 31 30.2 30.5 29.3 30.7 30.4 May 30.9 30.5 31.3 30.2 31.3 31.1 30.9 31.6 June 29.9 30.5 31.5 29.9 30.7 30.1 31.3 31.9 July 30.3 31.3 30.5 30.5 30.3 29.2 30.8 30.7 August 30.2 31.3 30.1 36.1 29.5 30.6 30.5 30.8 September 29.5 30 30.2 30.1 29.5 29.6 29.9 30.8 October 28.6 28.2 29.4 28.2 25.9 29.2 28.7 29.3 November 27.1 27 28.1 27.8 28 28 27.7 27.5 December 26.5 27.7 26.8 27.4 27.1 27 27.1 27.5

31 Annexure.15. Pressure data (in milli bar) for the last eight years

1996 1997 1998 1999 2000 2001 2002 2003 January 1011.9 1012.5 1012.3 1010.8 1011.0 1010.6 1011.5 1013.3 February 1011.2 1011.2 1012.4 1011.7 1009.6 1010.4 1012.6 1011.3 March 1009.1 1011.0 1010.5 1007.3 1009.0 1009.1 1009.7 1010.0 April 1007.4 1009.6 1009.0 1006.3 1006.6 1008.2 1008.0 10082 May 1010.3 1007.3 1006.9 1006.0 1006.3 1005.8 1009.2 1005.8 June 1005.8 1007.8 1005.8 1007.0 1005.8 1005.9 1005.3 1005.6 July 1006.4 1006.9 1006.0 1006.3 1005.7 1006.4 1007.0 1006.1 August 1006.6 1008.3 1006.7 1007.1 1006.9 1006.7 1007.4 1006.6 September 1006.3 1009.4 1006.7 1006.9 1007.2 1007.1 1008.3 1007.2 October 1007.8 1011.9 1008.2 1007.6 1008.1 1007.8 1008.9 1008.4 November 1009.6 1010.8 1009.1 1010.2 1009.2 1007.4 1010.2 1010.6 December 1011.5 1011.8 1011.5 1011.6 1011.0 1013.0 1012.3 1011.7

Report compiled by: Rajeev Kumar, Technical Assistant, IGCMC

32

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