SHORT COMMUNICATION

On the Record of a Spot-Fin Porcupine Fish, Diodonhystrix (Linnaeus, 1758) from Mandarmani, Bay of BengalCoast of West Bengal, India

Soma Aditya Bandyopadhyay

Received: 24 August 2013 / Revised: 12 October 2013 / Accepted: 29 October 2013

� Zoological Society, Kolkata, India 2013

Abstract A dead specimen of a spot-fin porcupine fish

Diodon hystrix was observed on the sea shore in Mandar-

mani, West Bengal, India. The fish weighed 2.7 kg,

76.5 cm in length and 2.54 cm in eye diameter. Although

distributed circumtropically and recorded from Indian

coastal waters, D. hystrix is not harvested at present, as a

part of commercial capture fishery. Scars and symptoms

ensuring trawler net trap caused death of the specimen.

This incident warrants for a strict vigil on fishing gear used

in this part of Bay of Bengal so as to ensure death escape of

non-target marine resources.

Keywords Mandarmani � Bay of Bengal coast �Porcupine fish � Tetrodotoxin � Fishing gear

Introduction

The present commentary deals with a particular variety of a

spot-fin porcupine fish Diodon hystrix (Linnaeus, 1758)

(Tetraodontiformes: Diodontidae) found along the coast of

Bay of Bengal at Mandarmani (Longitude 87.70, Latitude

24.78), West Bengal, India during a field visit in the month of

January, 2012. Although the fish D. hystrix bears little eco-

nomic importance in commercial fishery, a dead specimen

was encountered near fishing boats, as a discarded material.

Earlier record of D. hystrix from this region of Bay of Bengal

suggests that this non target fish species is vulnerable to

trawlers meant for catching marine fishes (Kar 1996).

Encounter of a dead specimen of D. hystrix in the present

case indicates continued killing of this non target species as a

part of commercial fisheries operation in the seas. Inappro-

priate mesh size of fishing gears and the net structure are

often cited as a reason for unwanted kill of non-target fish and

turtles (Raut and Nandi 1986; Thomas and Hridayanathan

2003; Peckham et al. 2007). Description of the dead speci-

men of D. hystrix would enable to corroborate this reason and

highlight other possible measures that would reduce the kill

of unwanted marine resources (Fig. 1).

Materials and Methods

The fish specimen (Diodon hystrix) was found lying dead

along the coast of Bay of Bengal at Mandarmani, West

Bengal, India on January 18, 2012 at around 5.30 a.m. It

was an identifiable member of the puffer fish family,

Diodontidae (Leis 1978, Biswas 2009). The specimen was

photographed; visible morphological characters and col-

oration were recorded. Upon examination it was noted that

the scaleless fish specimen has a stout body with bulbous

head and disproportionately large, expressive eyes, char-

acterized by long, sharp spines radiating all over the head

and body. It was light gray in colour on the dorsal side and

white underneath and small black spots were present all

over the body as well as fins. The teeth were fused together

into a single unit, creating a strong, beak-like mouth. It

weighed 2.7 kg and the total standard length was 76.5 cm

with eye diameter 2.54 cm.

Results and Discussion

The size of the present specimen of porcupine fish excee-

ded the earlier recorded specimen having 60 cm length

S. Aditya Bandyopadhyay (&)

Department of Zoology, Sarojini Naidu College for Women, 30,

Jessore Road, Dum Dum, Kolkata 700 028, West Bengal, India

e-mail: soma_bandyopadhyay@yahoo.com

123

Proc Zool Soc

DOI 10.1007/s12595-013-0087-y

TH

EZ

O

OLOGICAL SOC

IET

YKO LK ATA

with 1.8 kg body weight caught from the same region (Kar

1996). However, D. hystrix specimen with the body length

91 cm and biomass 2.8 kg is on record from the Pacific

coast (Eschmeyer et al. 1983; IGFA 2001). Though there

exist many possibilities of death of the specimen in ques-

tion, the visible scars and wounds on the ventral part of the

body suggesting trawling net trap is the lone reason. Por-

cupine fish have the ability to inflate their body by swal-

lowing water or air, thereby becoming sphere-shaped. This

increase in size reduces the range of potential predators to

those with much bigger mouth gape. A second defense

mechanism is provided by the sharp spines, which radiate

outwards when the fish is inflated. Some species are poi-

sonous, having tetrodotoxin in their internal organs, such

as the ovaries and liver (Halstead et al. 1990). As a result of

these three levels of defense, porcupine fish have few

predators, even though adults are sometimes preyed upon

by the dolphins and sharks.

Although considered poisonous, porcupine fish are

consumed in Pacific Islands like Hawaii and Tahiti. In the

Oriental region, the dried, inflated bodies are sold as tourist

novelties and the dried skins were used as war helmets in

Pacific Islands, in the past. Porcupine fish are also collected

for private and public show aquariums. This fish is not

categorized in Red List of Threatened Animals (IUCN

2012).

The porcupine fish D. hystrix is a widely distributed

species, found circumtropically and often in temperate

marine environments. The porcupine fish is the only

member of the genus Diodon to be found in the Mediter-

ranean Sea. In the eastern Pacific, it ranges from San

Diego, California (US) to Chile including the Galapagos

Islands (Ecuador). It is also found in the western Atlantic

from Massachusetts (US) to the northern Gulf of Mexico

south to Brazil. It also occurs in Bermuda. In the eastern

Atlantic it is generally found between 30�N and 23�S. In

India, it has been recorded earlier from Kavaratti atoll,

Bitra and Minicoy islands of Lakshadweep (Anand and

Pillai 2003), Gulf of Mannar-Tamilnadu (Kumaraguru

2000), Vizhinjam-Kerala (Bijukumar and Deepthi 2009),

Gujarat, Andaman and Nicobar islands (Talwar 1990) and

Digha, West Bengal (Kar 1996; ZSI 2010).

Considering the biogeographical distribution of D. hys-

trix, it is noteworthy to record such a specimen along the

coast of Bay of Bengal. Trawlers across the Digha coast of

Bay of Bengal, capture several edible fishes for commercial

purposes. Although D. hystrix is not included as a part of

capture fishery, instances of net-trapped specimens are on

record. Except in one case with 60 cm, generally, the size

of the trapped fish specimen is 30 cm (Kar 1996). From the

sizes of the trapped D. hystrix, it is likely that the width of

the net prevents escape of this unintended catch. Probable

Fig. 1 A–D The dead specimen of Diodon hystrix on the sea shore of Mandarmani, West Bengal. A The specimen as was observed on the sea

shore. B Characteristics of the small black spots covering the body and the fins. C The bulbous head region from lateral view showing the

characteristic large, expressive eyes and beak-shaped mouth. D Characteristics of the long sharp spines radiating all over the head and body. The

arrow indicates protrusion of internal organs through the damaged abdomen

Proc Zool Soc

123

interference with the movement of the trawlers, in course

of wandering in the coastal waters can increase the chances

of D. htystrix being trapped. In view of the described

habitats of D. hystrix, being lagoons and coral reefs, and

with shelled invertebrates as preferred food, occasional

catch in the trawlers cruising along the coast of Bay of

Bengal raises concern about judicial exploitation of marine

resources. Unwanted catches of non target marine organ-

ism has been a concern for long. Several non target species

including loggerhead turtles forced enactment of legisla-

tion resulting in refinement of fishing gears and norms for

practice for capture fisheries (Raut and Nandi 1986; Tho-

mas and Hridayanathan 2003; Peckham et al. 2007; FAO

2010). Despite D. hystrix being a species of least concern

under IUCN, human induced death is not commendable.

The present specimen cite a true example to consider fur-

ther refinement in the fishing gears and increased vigil on

the coastal exploitation to avoid this unintended death of a

non target marine resource. As a first record of porcupine

fish species from Mandarmani, West Bengal, India this

specimen warrants judicious fish catching methods to avoid

future loss of marine biodiversity.

Acknowledgments The author thankfully acknowledges the con-

structive views of the anonymous reviewers in upgrading the manu-

script to its present form. The author is thankful to the Teacher-in-

Charge, Sarojini Naidu College for Women, Kolkata, for the facilities

provided including preservation of the fish specimen. The author also

acknowledges the contribution of her students, Priyanka Das and

Gunjan Roychowdhury for locating the specimen in the sea beach.

References

Anand, P.E.V., and N.G.K. Pillai. 2003. Habitat distribution and

species diversity of coral reef fishes in the reefslope of the

Kavaratti atoll, Lakshadweep, India. Journal of the Marine

Biological Association of India, Cochin 45(1): 88–98.

Bijukumar, A., and G.R. Deepthi. 2009. Mean trophic index of fish

fauna associated with trawl by catch of Kerala, southwest coast

of India. Journal of the Marine Biological Association of India,

Cochin 51(2): 145–154.

Biswas, K.P. 2009. Fishes around Indian Ocean Muraenidae-Eel.

New Delhi: Daya publishing house.

Eschmeyer, W.N., E.S. Herald, and H. Hammann. 1983. A field guide

to Pacific coast fishes of North America. Boston: Houghton

Mifflin Company. 336 p.

FAO. 2010. Guidelines to reduce sea turtle mortality in fishing

operations. FAO: Rome. 128.

Halstead, B.W., P.S. Auerbach, and D.R. Campbell. 1990. A colour

atlas of dangerous -marine animals. Ipswich: Wolfe Medical

Publications Ltd.

IGFA. 2001. Database of IGFA angling records until 2001. Fort

Lauderdale: IGFA.

IUCN, 2012. IUCN Red List of Threatened Species.

Kar, S.K. 1996. On the largest spotted porcupine fish, Diadon hystrix

landed at Digha. Marine Fisheries Information Service 142: 16.

Kumaraguru, A.K. 2000. Studies on socioeconomics of Coral Reef

resource users in the Gulf of Mannar coast, South India. Centre

for Marine and Coastal studies School of Energy, Environment

and Natural Resources Madurai Kamaraj University, Madurai,

India.

Leis, J.M. 1978. Systematics and zoogeography of the Porcupine

fishes (Diodon, Diodontidae, Tetraodontiformes), with com-

ments on egg and larval development. Fishery Bulletin 76(3):

535–567.

Peckham, S.H., D.M. Diaz, A. Walli, G. Ruiz, L.B. Crowder, and

W.J. Nichols. 2007. Small-scale fisheries bycatch jeopardizes

endangered Pacific loggerhead turtles. PLoS One 2(10): e1041.

Raut, S.K., and N.C. Nandi. 1986. Net-bound death of olive ridley

turtle Lepidochelys olivacea. Journal of the Bombay Natural

History Society 83: 223–224.

Talwar, P.K. 1990. Fishes of Andaman and Nicobar Islands: a

synoptic survey. Journal of the Andaman Science Association,

Port Blair 6(2): 71–102.

Thomas, S.N., and C. Hridayanathan. 2003. Catch analysis in small

mesh gill nets. Indian Journal of Fisheries 50(3): 387–393.

ZSI. 2010. e-NEWS. 2 (6): June 2010.

Proc Zool Soc

123