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Long-term biological monitoring and stable isotope analysis of Aetobatus narutobiei in Ariake Bay, Japan: Feeding ecology and foraging impact on bivalve fisheries, Atsuko Yamaguchi [et al.]

Long-term biological monitoring and stable isotope analysis of Aetobatus narutobiei in Ariake Bay, Japan: Feeding ecology and foraging impact on bivalve fisheries, Atsuko Yamaguchi [et al.]

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Projects Abroad – Fiji Shark Program:

Linking Citizen Science to Fisheries

Management

Gauthier Mescam

1



∗ 1



Projects Abroad - Fiji Shark Conservation (FSCP) – Lot 2, Ventura apartment, PO BOX 588 Pacific

Harbour, Fiji



The number of citizen science projects focussed on marine conservation has increased globally

over the past two decades. Such projects are relatively simple to set up, are often self-financing,

and have an instantly accessible, growing market of volunteers. They can provide high volumes

of data sets that would otherwise be difficult to attain by single researchers or small teams. However, many projects lack reliability and replicability or are not conducted in cooperation with

NGOs and academic institutions. The ensuing lack of scientific analysis and limits the ability to

feed and translate into fisheries management and conservation processes. Of the known chondrichthyans, about half are classified as data deficient or haven’t been evaluated due to the lack

of national information, wrong geographic ranges, or taxonomic uncertainties. Well-managed

citizen science projects can provide much needed assistance to fill these gaps.

Project Abroad’s Fiji Shark Conservation Project (FSCP), based in Pacific Harbour, Viti Levu,

Fiji, was established in January 2014 to try to tackle national shark conservation issues, while

ensuring data integrity by providing training to volunteers. The FSCP is collaborating with

conservation NGOs and researchers from academic institutions to collect scientific data and to

address national shark conservation issues in Fiji.

The FSCP possesses now over three years of data of year round survey dives, baited remote underwater video camera deployments, and fishing surveys from various locations in the Southeast

of Fiji’s principal island, Viti Levu. The FSCP also conducts a mangrove ecosystem restoration

project, a critical ecosystem for many juvenile elasmobranchs, and features a significant education and awareness component with local communities, advocating the need to preserve the

resources of small island nations like Fiji.

Citizen science projects have the potential to provide much needed data for predatory fish

populations and key marine species, and contribute invaluably to fisheries management and development of appropriate conservation measures. However, to reach these goals, citizen science

projects require the support of academic expertise in order to provide and analyse robust, useful,

and credible data.







Speaker



295



Species diversity, utilization status and

conservation of sharks and rays in China

Jie Zhang



∗ 1



1

Key Laboratory of Animal Ecology and Conservation BiologyInstitute of Zoology, Chinese Academy

of Sciences (CAS) – No.1-5 Beichen Xilu Road, Chaoyang District, Beijing 100101, P. R. China, China



Chondrichthyans, which include sharks, skates and rays, originated 400 million years ago

with a further radiation throughout every world’s oceans and play a vital role in maintaining

the balance of marine ecosystem as top predators in the ocean. There are more than 1200 shark

species and their close relatives, skates, rays and chimaeras in the world, of which, 243 species

are recorded in China. That is, Chinese chondrichthyan fauna is at least one-fifth of the extant

species in the world. Chondrichthyan species composition in each Chinese Seas is as follows:

17 species in the Bohai Sea, 40 species in the Yellow Sea, 166 in the East China Sea, and 170

in the South Sea. According to the IUCN Red List of Threatened Species, 91 chondrichthyan

species in China were classified as threatened (critically endangered, endangered or vulnerable),

which meant nearly 40% of chondrichthyans in China faced with danger. There are currently 26

countries that have shark as their commercially important of fishery. Reliable information on

life history, population dynamic, distribution and exploitation of sharks and rays is very limited

in China. Consequently, it is impossible to perceive threat mechanisms of certain species and

to propose scientifically–sound policy on shark conservation and management. As a first step in

the conservation of shark in China, accurate and unambiguous identification of shark and shark

products using molecular method was constructed. Samplings were performed in fish ports, fish

markets and dry seafood markets in 32 cities along the coastal line of China mainland, from

November 2006 to August 2016. A total of 83 species, which include 64 species may distribute

in China Seas and 19 alien species, were utilized in China. The number of Carcharhiniformes

species was the most abundant, which makes up the bulk of utilized chondrichthyan species in

China. Utilization types of shark and ray products in China were various, including fresh meat

(43 species), salted meat (36 species), skin (22 species), fin(13 species), bone(vertebra, skull and

fin ray, 9 species), and dried gill(5 species). Some detailed information on the utilization and

conservation of CITES Appendix II species was also discussed.







Speaker



296



Stable isotope analysis of two filter feeding

sharks in the waters off Taiwan

Chi-Ju Yu



∗† 1



, Shoou-Jeng Joung 1 , Kwang-Ming Liu 1 , Hua-Hsun Hsu 2 ,

Chia-Yen Lin 1 , Atsuko Yamaguchi 3



1



2



National Taiwan Ocean University – No.2, Beining Rd., Jhongjheng District, Keelung City 202,

Taiwan (R.O.C), Taiwan

Marine Studies Section, Center for Environment and Water, Research Institute, King Fahd University

of Petroleum and Minerals – P.B. No. 2094, Dhahran 31261, Saudi Arabia, Saudi Arabia

3

Nagasaki University – 1-14 Bunkyo, Nagasaki City, Japan 852-8521, Japan



Feeding ecology is a good way to not only better understand the roles that animals play in

the ecosystem, but also provide useful information for future resources management. However,

most feeding studies in the past focused on high commercial value or high trophic level species,

yet the information of primary consumers or secondary consumers is still limited. Both whale

shark (Rhincodon typus) and megamouth shark (Megachasma pelagios) are filter feeders, but

they have different feeding mechanisms, occurring time and location. The aim of this study is

to understand the habitat utilization and feeding ecology of the two filtering shark species by

using stable isotope analysis. In total, the tissues of 81 whale shark (30 females, 2.84-11.90 m

TL; 51males, 2.86-7.20 m TL) and 29 megamouth shark (16 females, 3.41-7.10 m TL; 13 males,

3.63-4.84 m TL) were collected during 2008-2015. The prey items identified from 4 stomachs of

megamouth shark included shrimp, jellyfish, eggs, and scales of teleost fishes. The δ13C values

implied that both whale shark and megamouth shark moved from the open or deep waters to

the costal/shallow waters as they grow up. However, the δ15N values showed that these two

species have different feeding strategies. Whale shark has ontogenetic change in the diet; large

individuals have highly developed filtering structures on the gill-rakers and having the ability to

feed on prey with higher trophic level. However, due to the small sample size (n = 29), whether

megamouth change prey items in different life stages is still unclear. The trophic levels of these

two species were similar, which may be due to the similar body sizes of specimens. This study

provides the first information on feeding ecology for whale shark and megamouth shark in the

northwestern Pacific Ocean, but more specimens and factors including life stage, sex, and season

should be taken into account in future study.









Speaker

Corresponding author: wing13260@gmail.com



297



Taxonomic review of the longnose dogfish

genus Deania (Centrophoridae) from Japan

Akihiro Matsumoto 1 , Kenji Nohara 2 , Taku Horie 1 , Sho Tanaka



∗† 3



1



Tokai University, School of Marine Science and Technology – 3-20-1 Orido, Shimizu, Shizuoka

424-8610, Japan

2

Tokai University, School of Marine Science and Technology – 3-20-1 Orido, Shimiu, Shizuoka

424-8610, Japan

3

Tokai University, School of Marine Science an Technology – 3-20-1 Orido, Shimizu, Shizuoka,

424-8610, Japan



The genus Deania belongs to the family Centrophoridae with the other genus Centrophorus and is recognized to comprise 4 species: D. calcea, D. hystricosa, D. profundorum and D.

quadrispinosa. D. calcea and D. hystricosa are known to inhabit Japanese water. The former

was described briefly based on the specimen from Madeira by Lowe in 1839. Garman detailed

the description of the latter using the specimen from Japan in 1906. However, by the absence

of the D. calcea type, the taxonomy is still in a complex state. With the object of defining

the taxonomy of Deania in Japan, we examined the morphological characters of Deania species

collected from Japan and kept in several main Museums, including the type specimens, and

the morphometric measurements were processed by multi- dimensional scaling (MDS). Three

regions of mtDNA extracted from several Deania specimens without D. profundorum were sequenced and a NJ tree was drawn. D. calcea in Japan was distinguished from D. calcea in the

other localities in the dorsal fins and dermal denticles. Therefore Japanese D. calcea was designated tentatively as D. rostrata. MDS divided the Deania genus between a group of rostrata,

profundorum and quadrispinosa and a group of calcea and hystricosa. The NJ tree from the

sequences of mtDNA made three grades; D. rostrata, D. quadrispinosa and a mix of D. calcea

and D. hystricosa. The results suggest that 1) D. rostrata (Garman) 1906 is appropriate for

the scientific name of Japanese D. calcea, 2) D. calcea and D. hystricosa may be synonyms,

3) the genus Deania comprises at least 4 species; D. calcea or D. hystricosa, D. rostrata, D.

quadrispinosa, and D. profundorum. A key to the species is provided.









Speaker

Corresponding author: sho@scc.u-tokai.ac.jp



298



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Long-term biological monitoring and stable isotope analysis of Aetobatus narutobiei in Ariake Bay, Japan: Feeding ecology and foraging impact on bivalve fisheries, Atsuko Yamaguchi [et al.]

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