MARINE AND FISHERY SCIENCES 36 (2): 197-202 (2023)

https://doi.org/10.47193/mafis.3622023010505

ABSTRACT. Porpita porpita occurs in the tropical and sub-tropical waters of the Pacific,

Atlantic, and Indian Oceans, and the mass numbers of stranded colonies seem to be increasing.

Although its presence in Indian waters is minimal, this is the first record ever made of P. porpita in

Visakhapatnam coastal waters. The present study provided a detailed description of the species and

its global distribution. Further, the perceived increase in gelatinous zooplankton blooms in the

observed area indicates that jellyfish can negatively affect fisheries because they compete with zoo-

planktivorous fish, prey upon fish eggs and larvae, and indirectly compete with higher trophic levels

by reducing the plankton available to planktivores. Conversely, jellyfishes also play a vital role in

regulating global marine plankton food webs, spatio-temporal dynamics, and biomass, which is a

role that has been generally neglected so far.

Key words: Jellyfish, Porpitidae, fisheries, gelatinous zooplankton, food web.

Arribazón de medusa azul Porpita porpita en las playas de Visakhapatnam, India (Bahía occi-

dental de Bengala)

RESUMEN. Porpita porpita se encuentra en las aguas tropicales y subtropicales de los océanos

Pacífico, Atlántico e Índico, y el número masivo de colonias varadas parece estar aumentando. Aun-

que su presencia en las aguas de la India es mínima, este es el primer registro de P. porpita en las

aguas costeras de Visakhapatnam. El presente estudio proporcionó una descripción detallada de la

especie y su distribución global. Además, el aumento percibido en las floraciones de zooplancton

gelatinoso en el área observada, indica que las medusas pueden afectar negativamente a las pesque-

rías porque compiten con los peces zooplanctívoros, se alimentan de huevos y larvas de peces, e

indirectamente compiten con niveles tróficos más altos al reducir el plancton disponible para los

planctívoros. Por el contrario, las medusas también juegan un papel vital en la regulación de las

redes alimentarias del plancton marino global, la dinámica espacio-temporal y la biomasa, un papel

que generalmente se ha descuidado hasta ahora.

Palabras clave: Medusa, Porpitidae, pesquerías, zooplancton gelatinoso, trama trófica.

Porpita porpita (Linnaeus, 1758), commonly known as ‘blue button jelly’,

is a colony of Hydrozoa belonging to the Order Anthoathecata, Family Por-

pitidae, which includes three genera: Porpema Haeckel, 1888; Velella Lamar-

ck, 1801 and Porpita Lamarck, 1801. It is an open ocean species found glob-

ally in tropical and sub-tropical waters of the Pacific, Atlantic, and Indian

oceans (Zhang 1999; Kirkendale and Calder 2003; Bouillon et al. 2004;

197

*Correspondence:

silambuplankton@hotmail.com

Received: 22 January 2023

Accepted: 7 March 2023

ISSN 2683-7595 (print)

ISSN 2683-7951 (online)

https://ojs.inidep.edu.ar

Journal of the Instituto Nacional de

Investigación y Desarrollo Pesquero

(INIDEP)

This work is licensed under a Creative

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Marine and

Fishery Sciences

MAFIS

NOTE

Stranding of blue button jelly Porpita porpita (Cnidaria: Hydrozoa) on the

beaches of Visakhapatnam, India (Western Bay of Bengal)

SUJIT K. PATTNAYAK1, KRISHNAN SILAMBARASAN2, *, ANNADA BHUSAN KAR3, PRATYUSH DAS3and G. V. A. PRASAD3

1Fishery Survey of India, Kochi, India. 2Fishery Survey of India, Chennai, India. 3Fishery Survey of India, Visakhapatnam, India.

ORCID Krishnan Silambarasan https://orcid.org/0000-0001-5805-1562, Annada Bhusan Kar https://orcid.org/0000-0003-1431-6463

Kubota and Tanase 2007; Fisner et al. 2008;

Gravili et al. 2008; Calder 2010; Pandya et al.

2013; Gul and Gravili 2014). The species was

first described by Linnaeus (1758) as Medusa

porpita. Numerous nominal species of Porpita

Lamarck, 1801, have been described over the

years, but all are now synonymised for a single

species, P. porpita (Calder 1988; Schuchert

2013). It is inhabiting the ocean surface although

habitats of larvae and medusae may extend up to

200 m depth. This species is the dweller of the

uppermost layer of the marine environment and is

easily carried to shore by water currents and wind

(Pandya et al. 2013).

The species P. porpita actively feeds on

diverse zooplanktonic prey, including copepods,

cladocerans, larval forms of small crustaceans

and molluscs (Ganapati and Subba Rao 1959). In

addition, P. porpita colonies and medusae host

symbiotic zooxanthellae that may provide nutri-

tion. It is predated by a diverse vertebrate preda-

tor and specially gastropods, mostly Glaucus spp.

and Janthina spp. (Chowdhury et al. 2016; Lep-

oint et al. 2016; Phillips et al. 2017).

Porpita porpita is notable for forming huge

rafts at sea and for massive beach strandings and

aggregations that have been reported in various

parts of the world’s oceans (Chowdhury et al.

2016; Madkour et al. 2019; Mamish et al. 2019;

Gurlek et al. 2020; Sahu et al. 2020; Boukhicha

and Tilg-Zouari 2021). A total of 2,039 records

from the Indian Ocean can be found in the Ocean

Biogeographic Information System (OBIS) and

the Global Biodiversity Information Facility

(GBIF), of which 1,005 occurrences have been

reported so far, though other records may be

scattered throughout the literature and other bio-

geographic databases. This observation repre-

sents the blue button jelly P. porpita washed

ashore at Bheemunipatnam beach, and it is the

first record in Visakhapatnam coastal waters. In

addition, the present study discussed a detailed

description of the species, its distribution and the

negative impact of fishers.

On March 16th, 2021, a cluster of twenty

colonies of P. porpita were observed in Bheemu-

nipatnam village, Visakhapatnam (Western Bay

of Bengal). Out of twenty colonies, two P. porpita

specimens were transported for laboratory analy-

sis; later in the collection, specimens were exam-

ined visually and photographed. Specimens were

preserved in a 4% formaldehyde solution for fur-

ther anatomical studies. Anatomical details were

observed with a dissection microscope and

described following Ruppert et al. (2004) and Fox

(2007). Specimens were stored in separate glass

containers and deposited in the referral Museum

of Fishery Survey of India, Visakhapatnam.

The animal is a round, bright blue colour, float-

ing hydroid colony having a large, gas-filled flat

disc with a prominent central pore and numerous

minute pores radiating from the centre, no free-

floating sail, a single mouth beneath the float and

tentacles. The lower side of the disc has a small,

central gastrozooid with a terminal mouth and is

surrounded by many gonozooids, and dactylo-

zooids extending towards the periphery (Figure 1).

The hydroid colony has a large, disc-shaped

mantle and it floats on water’s surface. Polyps and

tentacles are finger-like projections that are sub-

merged on the underside of the water. The upper-

side is slightly convex, without tubercles, and the

central portion has a round elevation where a

small central pore (stigmata) is present. Upper

float and hanging polyps are present; there is a

large central mass made up of mesoglea penetrat-

ed by tubular, gastrodermal extensions. The cen-

tral region is hardened due to an internal chitinous

float (pneumatophore) containing a series of con-

centric air chambers with pores on the upper side.

The central part of the organ is covered by ecto-

dermal tissue and filled with cnidoblasts, which

are located between the upper and lower portion

of the central mass. The cnidoblasts drift to tenta-

cles and polyps, where they become stinging cells.

The colony is divided into three sections: a large

central gastrozooid, a median band of numerous

gonozooids, and a peripheral band of dactylo-

198 MARINE AND FISHERY SCIENCES 36 (2): 197-202 (2023)