@article{,

title = {New Determination of Prey and Parasite Species for Northern Indian Ocean Blue Whales},

author = {de Vos,Asha,Faux,Cassandra E.,Marthick,James,Dickinson,Joanne,Jarman,Simon N.},

url = {https://www.frontiersin.org/article/10.3389/fmars.2018.00104},

issn = {2296-7745},

year  = {2018},

date = {2018-01-01},

journal = {Frontiers in Marine Science},

volume = {5},

number = {84},

abstract = {Blue whales are little studied, face significant anthropogenic threats and within the Northern Indian Ocean, have a restricted range, making them an archetype for conservation needs of megafauna around the world. We studied feeding behaviour of blue whales using dietary DNA metabarcoding of faecal samples. While globally blue whale populations feed predominantly on Euphausiidae, 87 % of prey DNA amplicons extracted from faecal samples from this population were sergestid shrimp, demonstrating that blue whales can locate and feed on dense swarms of other types of prey when they occur. Within the Indian Ocean sergestids are present within the top 300 m, which correlates with the deep scattering layer observed by hydroacoustics. Studies suggest that this requirement to dive deeper in search of prey likely explains the prevalence of fluke up diving within this population of blue whales relative to other parts of the globe. Furthermore, this study revealed the presence of acanthocephalan endoparasites within the stomach and intestines of the Northern Indian Ocean blue whales. This represents the first record of Acanthocephala in blue whales in the Northern Indian Ocean and highlights the need for further studies on both the ecto- and endoparasitic flora and monitoring of health of these cetaceans for their management and conservation.},

keywords = {Acanthocephala, Arabian Sea, balaenoptera musculus, behaviour, blue whales, DNA metabarcoding,Sri Lanka,Blue whales,feeding,Northern Indian Ocean,faeces,Sergestid,Euphausiidae,Acanthocephala,shrimp,krill,behaviour, euphasids, Faeces, fecal analysis, feeding, Krill, Northern Indian Ocean, parasites, prey, Sergestid shrimp, shrimp, Sri Lanka},

pubstate = {published},

tppubtype = {article}

}

@article{,

title = {First record of Omura’s whale, Balaenoptera omurai, in Sri Lankan waters},

author = {de Vos, Asha},

url = {http://dx.doi.org/10.1186/s41200-017-0121-2},

issn = {1755-2672},

year  = {2017},

date = {2017-01-01},

journal = {Marine Biodiversity Records},

volume = {10},

number = {82},

pages = {18},

abstract = {An unusually coloured, small baleen whale was documented off the southern coast of Sri Lanka in February 2017 during routine field surveys. Based on five distinct morphological characteristics including jaw asymmetry, presence of a prominent central rostral ridge, blaze on right side, asymmetrical chevron on left and right sides and a strongly falcate dorsal fin the individual was positively identified as an Omura’s whale (Balaenoptera omurai). This discovery represents the first confirmed sighting of Omura’s whale in Sri Lankan and therefore central Northern Indian Ocean waters.},

keywords = {Arabian Sea, balaenoptera omurai, Distribution, Northern Indian Ocean, Omura's Whale, Sri Lanka},

pubstate = {published},

tppubtype = {article}

}

@article{,

title = {Cetaceans and tuna fisheries in the Western and Central Indian Ocean},

author = {Anderson, R Charles},

url = {http://www.fao.org/3/a-bg252e.pdf},

year  = {2014},

date = {2014-01-01},

journal = {International Pole and Line Federation Technical Report},

volume = {2},

number = {10},

pages = {133},

abstract = {This report reviews information on interactions between cetaceans (whales and

dolphins) and tuna fisheries in the western and central Indian Ocean. The average

annual catch of tuna and related species in the Indian Ocean was just over 1.5 million

tonnes during 2008-12. Of this, almost 1.1 million tonnes (71%) came from the

western and central Indian Ocean. The main fisheries for tuna and tuna-like species

in the region are gillnet (40% of reported catch during 2008-12), purse seine (26%),

longline (12%), handline and troll (11%) and pole-and-line (9%).

Major gillnet fishing nations include Iran, India, Sri Lanka, Pakistan, Oman and Yemen.

Cetacean bycatch must be large, but is poorly documented. A rough estimation,

based on the limited published information available, suggests that something

in excess of 60,000 small cetaceans might be taken as bycatch each year. There is

an urgent need for monitoring and management of these fisheries including the

development of mitigation methods to reduce cetacean bycatch. Large-scale gillnetting

on the high seas (using nets in excess of 2.5km length) is banned by both

UN convention and IOTC resolution, but is being carried out by Iran, Pakistan and

possibly also other countries; compliance is required. More generally, the large and

still expanding gillnet capacity within the region needs to be assessed, and if appropriate

either capped or reduced.

Purse seining in the western and central Indian Ocean is dominated by French and

Spanish fleets. An increasing proportion of sets is made on drifting fish aggregating

devices (FADs) but there has been, and continues to be, a considerable number of

sets made on free schools (i.e. non-FAD-associated tuna schools). Most cetaceans do

not regularly associate with FADs and the major potential cetacean interactions are

with free school sets. During 1981-1999, 9.6% of all sets were reported to have been

made in association with baleen whales, probably Bryde’s whales (Balaenoptera

brydei). When encircled, most whales are reported to escape by breaking through

the net. Mortality is unknown, but may have been of the order of 10s annually. The

association of free schools of large yellowfin tuna with dolphins (mostly spotted

dolphins Stenella attenuata and spinner dolphins Stenella longrostris) is more contentious.

This association (which is common in the Eastern Tropical Pacific and is

exploited by the purse seine fishery there) has always been reported to be rare in the

western Indian Ocean. However, the tuna-dolphin association is common in many

coastal areas of the region and widespread in the high seas of the western Indian

Ocean north of 10°S. Setting on dolphin schools has been also reported to be rare,

but its true scale is questioned. Setting on cetaceans has recently been banned by

EU regulation (2007) and IOTC resolution (2013), so cetacean bycatch and mortality

should be much reduced in the future. 100% coverage by international observers

would be ideal.

Longline fisheries were dominated for several decades by East Asian nations, but

now increasing catches are made by coastal countries, notably India, Sri Lanka and

Seychelles. A major issue for longliners is depredation – removal of bait and damage

of hooked fish by sharks and cetaceans. Several species of cetacean have been

implicated, but the main one appears to be the false killer whale (Pseudorca crassidens).

There is also some entanglement of cetaceans in longlines (likely following

attempts at depredation). Development of mitigation measures is on-going and

needs to be continued. It is possible that some longline fishermen are deliberately

killing cetaceans.

Several coastal countries have handline fisheries for large yellowfin tuna, which fishermen

locate by their association with dolphins (mainly spotted and spinner dolphins).

There is anecdotal evidence that some dolphins are hooked. Although they

invariably break free or are released, the scale of any post-release mortality or of

sub-lethal impacts is unknown. From the Maldivian pole-and-line fishery, there are

reports of dolphins (probably Indo-pacific bottlenose dolphins, Tursiops aduncus)

taking fish attracted by the lights used during night bait fishing. The scale and potential

impacts of these interactions require assessment.

There has been a widespread failure to monitor and manage cetacean bycatch in

Indian Ocean tuna fisheries, and to develop and implement mitigation measures.

The enormous, and still growing, gillnet capacity in the region should be of particular

concern. There is a need for increased observer coverage of all fisheries, supplemented

by electronic monitoring. Fishery-independent surveys of cetacean distribution

and abundance in the western Indian Ocean are also required to inform

management.},

keywords = {Arabian Sea, Bycatch, cetaceans, Fisheries, Gill net, mitigation, Northern Indian Ocean, Regional management units, Tuna},

pubstate = {published},

tppubtype = {article}

}

@article{,

title = {Surfacing characteristics and diving behaviour of blue whales in Sri Lankan waters},

author = {de Vos, Asha,Christiansen, Fredrik,Harcourt, Robert G.,Pattiaratchi, Charitha B.},

url = {http://www.sciencedirect.com/science/article/pii/S0022098113003298},

issn = {0022-0981},

year  = {2013},

date = {2013-01-01},

journal = {Journal of Experimental Marine Biology and Ecology},

volume = {449},

number = {83},

pages = {149-153},

abstract = {Surfacing behaviour and dive characteristics were quantified from focal follows of individual blue whales between January–March 2012 and 2013. During this period individual whales were followed from small boats to observe their surfacing patterns and breathing behaviour. Data on time at first surface, length of surface interval, number of blows, final dive time and whether or not the whale ‘fluked up’ before a deep dive were recorded. A step-wise modelling approach was used to estimate a number of surfacing characteristics: mean Inter-Breath Interval (IBI), bout duration and the number of surfacings in a bout. First, dives were classified as either surface dives or deep dives based on the occurrence of arching or fluking behaviour at the surface prior to a deep dive. The mean IBI of surface dives was 17.6s (SD=26.14) and for deep dives, 640.3s (SD=214.38). To account for temporal dependence between dive types, a first-order Markov chain was used to estimate the transition probability between dive types. Time series of dive types were then simulated, using Monte Carlo methods, while accounting for heterogeneity in IBI of the different dive types. The mean IBI of blue whales in Sri Lanka, obtained from the Monte Carlo methods, was 84.7s (SD=11.17). The mean bout duration was 145s (SD=28.31), with the mean number of breaths per surface bout being 9.3 (SD=1.43). Whales also lifted their tail flukes out of the water on 55% of terminal dives, which is considerably more frequent than elsewhere in the world. These results significantly advance our understanding of blue whales in Sri Lankan waters. More specifically, this information is essential for the calculation of precise abundance estimates as it informs the detection probability parameters for line transect surveys. In this way it will help formulate better management decisions related to the conservation of this population.},

keywords = {Arabian Sea, availability bias, balaenoptera musculus, Blue whale, Markov chains, Monte Carlo, Northern Indian Ocean, ship strike, Surfacing behaviour, Whale watching},

pubstate = {published},

tppubtype = {article}

}

@article{,

title = {Exploring anthropogenic activities that threaten endangered blue whales (Balaenoptera musculus) off Sri Lanka},

author = {Ilangakoon, A. D.},

url = {http://www.oers.ca/journal/volume5/issue1/Ilangakoon_Gallery.pdf},

year  = {2012},

date = {2012-01-01},

journal = {Journal of Marine Animals and their Ecology},

volume = {5},

number = {114},

pages = {3-7},

abstract = {The waters off Sri Lanka, an island in the northern Indian

Ocean, are an important habitat for blue whales, a species listed as

Endangered in the IUCN Red List of Threatened Species. The

subspecies status, genetic affinities and movement patterns of this

northern Indian Ocean population of blue whales is not yet clearly

understood but off Sri Lanka they can be found throughout the

year. Sri Lanka also lies on a busy international shipping lane. Since

2009 a boat-based commercial whale-watching industry targeting

the blue whale, has been developing off the south coast, with

annual growth in numbers of boats and visitors. This industry

however remains unregulated in any formal or informal manner due

to the absence of regulatory mechanisms in this small, developing,

island nation. Consequently unethical practices are leading to

harassment resulting in direct and indirect impacts on the targeted

whales. Sighting and stranding data from before and after the

inception of whale watching activities indicate a spatial shift in the

area of occurrence and concentration of whales and a corresponding

increase in fatal vessel collisions along the southwest coastline of

the island. There are clear indications of displacement from

preferred near-shore feeding areas to the vicinity of the adjacent

shipping lane, causing an increase in collision risk. Although these

findings are based on limited data, it is recommended that a

precautionary principal is followed and anthropogenic activities are

quickly regulated to mitigate adverse impacts on these endangered

blue whales. },

keywords = {Arabian Sea, balaenoptera musculus, Blue whale, impacts, Northern Indian Ocean, shipping, Sri Lanka, Whale watching},

pubstate = {published},

tppubtype = {article}

}