Observation
of a Whale Shark Rhincodon typus(Orectolobiformes: Rhincodontidae) in the offshore waters of
Rushikulya, Orissa, India
Sajan
John
Wildlife Institute of India, PB#18, Chandrabani,
Deharadun, Uttarakhand 248001, India
Email: johns@wii.gov.in,sajanjohn09@gmail.com
Date of publication (online): 26 May
2010
Date of publication (print): 26 May
2010
ISSN 0974-7907 (online) | 0974-7893
(print)
Editor: Sanjay
Molur
Manuscript details:
Ms # o2245
Received 26 June 2009
Final received 25 March 2010
Finally accepted 08 April 2010
Citation:John, S. (2010). Observation of a Whale Shark Rhincodon typus (Orectolobiformes: Rhincodontidae) in the
offshore waters of Rushikulya, Orissa, India. Journal of Threatened Taxa 2(5): 896-897.
Copyright: ©
Sajan John 2010. Creative Commons Attribution 3.0 Unported License. JoTT allows
unrestricted use of this article in any medium for non-profit purposes,
reproduction and distribution by providing adequate credit to the authors and
the source of publication.
Acknowledgement: Thanks
to WII-DGH Sea turtle telemetry project for the logistics, Adhith Swaminathan
for providing the photographs, William Driggers (NOAA) for reviewing the
manuscript, Suresh Kumar (WII), B.M. Praveen Kumar (WTI) for suggestions, C.E.
John (NBFGR/CMFRI), P.M. Vipin (CIFT) for providing the references and my field
assistants at Rushikulya, Orissa.
The Whale Shark Rhincodon typusSmith, 1828 grows to a length of approximately 12m and a weight of
approximately 30 ton making it not only the largest fish but also one of the
largest extant animals. Despite
its size, wide-ranging distribution and the ease with which it is identified,
Whale Shark sightings are infrequently reported. The rarity of Whale Shark sightings has thus resulted in
global concern regarding the health of whale shark populations. This concern led to the species being
assigned Vulnerable status by the IUCN Red List of Threatened Species (Norman
2005). Additionally, Whale Sharks are protected in
India under Schedule-I of the Indian Wildlife (Protection) Act – 1972
(IWPA 2003).
On 22 February 2009, a Whale
Shark, accompanied by two sucker fish (Remora sp.) was sighted at 1120hr (IST), 3km
offshore and 12km north of the Rushikulya River mouth (85o10’18.26N
& 19o26’28.45E). Bottom depths at the sighting location ranged from 18-20 m; however, the
shark was primarily observed at the surface (Images 1 & 2). The atmospheric
and sea surface temperatures at the sighting location were 310C and
290C respectively; salinity was 34%. The length of the whale shark was between 4.5-5 m based on
its size relative to the 7m boat from which the observation was made. As the length at maturity for Whale
Sharks is reported to be above 9m (Colman 1997), the shark we observed was
likely a juvenile. Interestingly,
most Whale Sharks reported globally range from 4-10 m in length (Colman 1997)
and in Indian waters, 25% of the recorded whale sharks are between 5-6 m in
length (Pravin 2000).
Sightings of Whale Sharks
have been reported from almost all maritime states of India including Gujarat
(Hanfee 2001), Maharashtra (Jadhav et al. 2005), Karnataka (Kemparaju et al.
2002), Kerala (Paul 2006), Tamil Nadu (Rajapackiam et al. 2006), Andhra Pradesh
(Rao 1992), West Bengal and Goa (Pravin 2000; Choudhary 2008). Recently, there has been an increase in
Whale Shark sightings off the Orissa coast, such as those documented by Bar
(1998) and Rao (2004). Additionally, On March 2008, fishermen of Purnabandha Village (village
near Rushikulya River mouth) reported a Whale Shark approximately 4km offshore
near Rushikulya River mouth (Suresh Kumar, WII pers. comm. 27 February
2009). Furthermore, the Orissa
Diary (Anonymous 2009a) reported the stranding of a dead, 5.5m Whale Shark at
Gopalpur (a coastal town, 25km south of Rushikulya) in February 2009 and The
Hindu (Anonymous 2009b) reported about beaching of another Whale Shark at
Gopalpur on November 2008. Whether
or not the increase in observations of Whale Sharks from the region reflects an
increase in the abundance of the species or a result from increased public
interest in the species is unknown. However, it is evident that Whale Sharks inhabit the Orissa coast with
an unknown periodicity.
REFERENCES
Anonymous (2009a). Dead
whale shark recovered from Gopalpur beach. Orissa diary. <http://www.orissadiary.com/Shownews.asp?id=10541>.
On line version dated 03 February 2009.
Anonymous (2009b). Whale
shark washed ashore. The Hindu.
<http://www.hindu.com/2009/02/03/stories/ 2009020351020300.htm> 03
February 2009.
Bar, S. (1998). On a
whale shark landed at Paradeep, Orissa. Marine Fisheries Information Service, Technical and Extension Series155: p 20
Choudhary, R.G., A. Mookerjee, V. Menon &
D. Joshi (2008). Turning
the Tide - The Story of A Campaign to Save Vhali, The Whale Shark in Gujarat.
Wildlife Trust of India, New Delhi, 14pp.
Colman, J.G. (1997). A review
of the biology and ecology of the whale shark. Journal of Fish Biology 51: 1219-1234
Hanfee, F. (2001). Trade in
Whale shark and its products in the coastal state of Gujarat, India. Report to
the Rufford Foundation. TRAFFIC India.
Jadhav, D.G., B.B. Chavan, A.D. Sawant & S.
Sundaram (2005). On a Whale Shark, Rhiniodon typus landed at Versova, Mumbai. Marine Fisheries Information Service,
Technical and Extension Series 18(186): 18.
Kemparaju, S., L. Muniyappa & H.S.
Mahadevaswamy (2002).on a Whale Shark Rhiniodon
typus landed at Malpe, Udupi district, Karnataka. Marine Fisheries Information Service, Technical and Extension
Series 171: 9.
Norman, B. (2005). Rhincodon typus. In: IUCN
2010. IUCN Red List of Threatened Species. Version 2010.1. <www.iucnredlist.org>.
Downloaded on 16 April 2010.
Paul, S.
(2006). Whale Shark Rhiniodon typus landed at
Kollam. Marine
Fisheries Information Service, Technical and Extension Series 190: 22.
Pravin, P. (2000). Whale
Shark in the Indian Coast - Need for Conservation. Current Science 79(3): 310-315.
Rajapackiam,
K. & S. Mohan (2006). A giant Whale Shark (Rhincodon typus)
caught at Chennai fisheries harbour. Marine Fisheries Information Service, Technical and Extension Series 189:
25.
Rao, C.V.S. (1992). The
occurrence of Whale Shark Rhiniodon
typus along the Kakinada coast. Marine Fisheries Information Service, Technical and Extension Series 116:
19.
Rao, S.V.S. (2004). Landing
of Whale Shark, Rhiniodon typus at
Gopalpur Ganjam District, Orissa. Marine
Fisheries Information Service, Technical and Extension Series 181: 14.
IWPA (2003). The Wildlife (Protection) Act, 1972. Wildlife Trust of India & Natraj
Publishers, Dehradun, India, 149-163pp.