Advances in Animal and Veterinary Sciences

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AAVS_8_11_1161-1169

Research Article

Diversity and Current Status of Grouper Fish, Epinephelus Bloch, 1793 in Indian Coastal Waters

Darwin Chatla, Padmavathi Pamulapati*

Department of Zoology and Aquaculture, Acharya Nagarjuna University, Nagarjuna Nagar -522510, Andhra Pradesh, India.

Abstract | The grouper fish, Epinephelus Bloch, 1793 represents an iconic genus of the family Serranidae and order Perciformes. They are highly-prized food fishes intended for subsistence, artisanal, recreational and commercial fisheries throughout their geographic range. Despite their economic importance, the status of grouper fishes has been increasingly imperiled through overfishing activities. The conservation efforts have also been constrained with this highly skewed Epinephelus. Hence, in order to save this esteemed resource, effective conservation and rehabilitation strategies need to be planned and implemented in the country. However, it requires the knowledge of the current status of grouper fish diversity which is not yet carried comprehensively. Hence this study was proposed to review the systematic study of the genus Epinephelus to fill the gaps in diversity studies of India. The study also documented the present IUCN status of the listed species of Epinephelus under different categories of conservation status.

Keywords | Conservation, Distribution, Diversity, Epinephelus, Groupers

Received | June 13, 2020; Accepted | August 15, 2020; Published | September 01, 2020

*Correspondence | Padmavathi Pamulapati, Department of Zoology and Aquaculture, Acharya Nagarjuna University, Nagarjuna Nagar -522510, Andhra Pradesh, India; Email: [email protected]

Citation | Darwin C, Padmavathi P (2020). Diversity and current status of grouper fish, Epinephelus Bloch, 1793 in Indian coastal waters. Adv. Anim. Vet. Sci. 8(11): 1161-1169.

DOI | http://dx.doi.org/10.17582/journal.aavs/2020/8.11.1161.1169

ISSN (Online) | 2307-8316; ISSN (Print) | 2309-3331

Copyright © 2020 Chatla and Pamulapati. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.

INTRODUCTION

India is one of the twelve megadiverse nations in the world and well known for its biodiversity richness (Serajuddin et al., 2018) with a distinctive biogeographic marine ecoregion (Spalding et al., 2007). The Indian coastline (7517 km) with different coastal ecosystems supports rich diverse resources having considerable economic importance. The marine diverse resources represent half of all extant vertebrates with an estimation of 2443 (75.6%) valid species (Gopi and Mishra, 2015). In recent decades, there has been a massive development of the fisheries sector in the Indian waters. The vessels now extend their trawling operations into deeper waters, catching more varieties of demersal fishes including groupers. Grouper landings have been continuously increasing during the last decade (2009-2018) with an average of 37970 tonnes and are shown in Figure 1. The highest landings of 53924 tonnes in 2017 and the lowest of 17606 tonnes were observed in 2009. In 2018 the landings have been accounted for about 51433 tonnes (CMFRI, 2019). However, species-specific landing data were not reported for the grouper species. Because of this low degree of resolution, 61% of grouper landings are reported as “groupers nei” in FAO (2016) database. Concurrent with the increase in landings and production of groupers, there may be a chance of overexploitation and some species on the threat of extinction.

Grouper fishes are cosmopolitan, occurring in tropical and subtropical areas (Heemstra and Randall, 1993). This highly diverse fish group plays a significant role in the coral reef ecosystem as regulators of the structure and composition of communities and forms an important link in the food chain (Rao, 2009). The groupers are top predators, sedentary and usually sluggish in movement, slow growing and long-lived (Heemstra and Randall, 1993). They have white, tender and tasty meat, and commands a high price in the market. Moreover, many species have been prioritized as potential species for aquaculture (Noikotr et al., 2013; Pierre et al., 2008). Small grouper species are highly valued in the aquarium trade and remain as one of the valuable fishery resources along the coasts of India. These features attracted many enthusiastic researchers (Ottolenghi et al., 2004; Sadovy et al., 2013).

Figure 1: Trend of Grouper fish landings in India (2009-2018) (Source: CMFRI).

Over the past decade, a number of articles published on various aspects of Epinephelus species (Figure 2). In India, only 318 articles are published to an estimated 3386 articles worldwide. Thus, inspite of their commercial importance, the work done so far on Epinephelus species in India is scarce.

Figure 2: Number of articles published on Epinephelus in the last decade from India vs. world (Source: Science Direct, April 2020).

A perusal of the literature shows that these fishes are being subjected to intense fishing pressure for food, ornamental display and medicinal purposes globally (Sujatha et al., 2015; Vincent, 2006). The loss of groupers can have a serious effect on local ecosystems since these fishes play an important role in the structure of rocky bottom and coral reef communities (Sujatha et al., 2015). In spite of their commercial importance, the status of grouper fishes has been threatened by overexploitation. As a result, certain species of groupers have become a matter of serious concern. Hence, comprehensive information on the current status of grouper diversity is a prerequisite for efficient management and to formulate the steps to be taken to protect these fishes towards sustainable exploitation. Hence the present study was aimed to manifest the diversity and current status of Epinephelus in Indian coastal waters by reviewing the studies carried so far on the diversity and distribution of this fish. The Conservation status of Epinephelus species under different categories was also documented.

Diversity and Distribution of groupers, Epinephelus

Grouper fishes of the Family Serranidae (Order: Perciformes; Class: Actinopterygii) are represented by 16 genera and 163 species with world-wide distribution. According to FishBase, around 54 species of the sub-family, Epinephelinae and 38 species of the genus, Epinephelus have been reported from the Indian waters (Froese and Pauly, 2019). Groupers inhabit a wide variety of habitats, mainly coral reefs, rocky areas, seagrass beds, and estuaries (Darwin et al., 2018; Rao, 2009). They exhibit a wide variety of reproductive and growth strategies (Morris et al., 2000). Epinephelus species are regularly landed by subsistence, artisanal, and commercial fisheries throughout their geographic range. A significant number of studies have been carried on the diversity of groupers, Epinephelus in various ecosystems of the Indian coastal waters and are presented in Table 1.

Figure 3: Species richness against the length of the coastline of all coastal states and union territories

Data on the distribution of Indian groupers were collected from twelve coastal states and union territories of India (Figure 3) which revealed the presence of 47 species of Epinephelus in Indian waters (Table 2). The species richness against the length of the coast of all states and union territories is presented in Figure 3. The east coast represents 76.59% with 36 species, while the west coast

Table 1: Diversity studies on Epinephelus species in Indian coastal waters.

S. No.	State	Location	Reference
1	Gujarat	Location not mentioned	James et al., 1994
		Major coastal states of Gujarat	Barman et al., 2000
		Gulf of Kachchh	Subba Rao and Sastry, 2005
		Veraval	Joshi et al., 2018; Sen et al., 2019
2	Maharashtra	Location not mentioned	James et al., 1994
		Major fish landing centres of Maharashtra	Barman et al., 2012
		Sassoon Dock	Albert et al., 2017
		Mumbai Coast	Bhendekar et al., 2019
3	Goa	Grand Island	Sluka and Lazarus, 2010; Sluka, 2013
4	Karnataka	Natrani Island	Sluka and Lazarus, 2010; Sluka, 2013
		Major fish landing centres of Karnataka	Barman et al., 2013
		Mangalore, Karnataka	Mahesh et al., 2014
5	Kerala	Location not mentioned	James et al., 1994
		Ponnani estuary, Kerala	Bijukumar and Sushama, 2000
		Neendakara, Sakthikulangara, Munambam, Ponnani, Puthiyappa, and Azheekkal of Kerala	Biju and Deepthi, 2009
		Vizhinjam	Sluka and Lazarus, 2010
		Cochin	Gibinkumar et al., 2012; Anjali et al., 2019
		Vizhinjam	Sluka, 2013
		Location not mentioned	Bijukumar and Raghavan, 2015
		Mulloor, Vizhinjam, Kovalam, Thirumullavram of South Kerala	Baiju et al., 2016
6	Tamil Nadu	Parangipettai	Ramaiyan et al., 1987
		Location not mentioned	Ramesh et al., 2008
		Chennai metropolitan city limits (extending from Ennore in the north to Thiruvanmiyur in the south) Chennai	Krishnan et al., 2007
		Melakkal and Muttom	Sluka and Lazarus, 2010
		All coastal districts (10) Tamilnadu	Barman et al., 2011
		Mandapam and Keelakkarai	Roy and Gopalakrishnan, 2011
		Cuddalore and Parangipettai	Sambandamoorthy et al., 2015
		Nagapattinam	Ramu et al., 2015
		Wadge bank, Kanyakumari	Karuppasamy, 2016
		Pulicat	Govindan and Ravichandran, 2016
		Estuarine wetlands of Tamil Nadu	Mogalekar et al., 2017
		Cuddalore, Parangipettai, and Nallavadu	Jayaprabha et al., 2018
		Tuticorin, Southeast coast of India	Manojkumar et al., 2019
		Gulf of mannar	Varghese et al., 2011; Kumar et al., 2013; Joshi, 2016
		Thoothukudi Coast, Gulf of mannar	Jawahar et al., 2013
		Pamban, Gulf of mannar	Varghese and Joshi, 2017
		Keelakari, Gulf of mannar	Varghese et al., 2017
		Mandapam	Varghese and Gandhi 2019
		Thoothukudi	Anjali et al., 2019
7	Pondicherry	Pondicherry and Karaikal	Mishra and Krishnan, 2003
8	Andhra Pradesh	Major landing stations of Andhra Pradesh	Barman et al., 2004
8	Andhra Pradesh	Visakhapatnam	Sujatha, 2004; Sreedhar et al., 2010; Deepti et al., 2014; Sujatha et al., 2015
9	Orissa	Odisha	Barman et al., 2007
9	Orissa	Chilaka	Mohanty et al., 2015
S. No.	State	Location	Reference
10	West Bengal	Digha	Yennawar et al., 2011; Yennawar et al., 2015, 2017
		Digha, Digha Mohana, Shankarpur, Petuaghat, Sagar, Fresergunge, Namkhana, Kakdwip and Diamond Harbour of West Bengal coast	Kar et al., 2017
		Digha Mohona	Ray and Mohapatra, 2020
11	Lakshadweep Islands	Lakshadweep	Chandrasekhara, 1991; Murty, 2001; Kumar et al., 2012
11	Lakshadweep Islands	Minicoy Island	Robert and Lazarus, 2006
12	Andaman and Nicobar Islands	Andaman and Nicobar	Pokapunt et al., 1993; Rajan, 2001, 2015; Rajan et al., 2013; Rao, 2009; Kirubasankar et al., 2013; Ramakrishna et al., 2010

represents 57.44% with 27 species. The Andaman and Nicobar islands represent 70.21% of grouper diversity with a maximum number of 33 species, followed by Tamil Nadu (68.08%) with 32 species, Kerala (53.19%) with 25 species, Andhra Pradesh (42.55%) with 20 species, Karnataka (38.29%) with 18 species, Maharashtra 38.29% with 18 species, Lakshadweep (34.04%) with 16 species, West Bengal (29.78%) 14 species, Gujarat (29.78%) with 14 species, Orissa (17.02%) with 8 species, Goa (8.51%) with 4 species and Puducherry (6.38%) with 3 species.

Regarding species distribution (Table 2), E. coioides was recorded as a dominant species in all coastal states except Puducherry. Similarly, E. malabaricus was identified as the second most widely distributed species in the coastal waters of 10 out of 12 states and union territories in India. Considering the distribution of species from the west coast, E. coioides, E. diacanthus, and E. erythrurus were abundant in all reported stations, while E. areolatus, E. chlorostigma, E. fasciatus, E. fuscoguttatus, E. latifasciatus, and E. malabaricus are dominant in all stations, except Goa. Along the east coast, E. lanceolatus and E. malabaricus were reported in all stations, while E. bleekeri, E. coioides, E. latifasciatus and E. tauvina were found in all stations except Puducherry. The distribution of some rare species was confined to particular regions of the east coast such as E. corallicola (Tamil Nadu), E. fasciatomaculosus (Tamil Nadu), E. hata (Andhra Pradesh), E. magniscuttis (Andhra Pradesh and West Bengal), E. marginatus (Andhra Pradesh), E. melanostigma (Tamil Nadu), E. miliaris (Tamil Nadu), E. poecilonotus (Tamil Nadu), E. retouti (Tamil Nadu), E. rivulatus (Tamil Nadu) and E. sexfasciatus (Tamil Nadu and West Bengal), whereas E. bontoides (Kerala), E. chabaudi (Karnataka and Kerala), E. stoliczkae (Maharastra and Karnataka) and E. Tukula (Goa and Maharastra) were restricted to the west coast of India. In addition to these mainland coastal water species, some species such as E. amblycephalus, E. macrospilos and E. polystigma are reported only from Andaman and Nicobar Islands, while E. ongus and E. spilotoceps were recorded from both Lakshadweep, and Andaman and Nicobar Islands of India.

It is evident that among the 47 Epinephelus species registered in India, 40 are commercial, while the remaining species are used for aquaria, game/sport fishery, subsistence fisheries and aquaculture (Table 2). In India, rearing of groupers in brackish water aquaculture is a relatively new development as a diversification option in pond and cage culture farms and is still in R and D phase. Certain behavioral characteristics with a high degree of territoriality and site specificity are making the groupers at risk and easy targets for fishermen (Heemstra and Randall, 1993; Morris et al., 2000; Sadovy et al., 2013). In this context, groupers are emerged as a particularly vulnerable group of fishes (Ranjan, 2015). The apparent vulnerability of the giant grouper, E. lanceolatus of Andaman and Nicobar Islands is protected under schedule I of the Wildlife (Protection) Act, 1972.

Regarding the conservation status as per the IUCN Red List of Threatened Species, out of 47 Epinephelus species reported from Indian coastal waters, 41 species (87.23%) are marked as Least Concern (LC) and 3 species (6.38%) each as Vulnerable (VU) and Data deficient (DD) (Table 2 and Figure 4).