Pelagic shark bycatch in the New Zealand tuna longline fishery

2001 ◽  
Vol 52 (2) ◽  
pp. 165 ◽  
Author(s):  
Malcolm P. Francis ◽  
Lynda H. Griggs ◽  
Susan Jane Baird
Keyword(s):  
New Zealand ◽  
Pacific Ocean ◽  
Temporal Trends ◽  
Longline Fishery ◽  
Catch Per Unit Effort ◽  
Prionace Glauca ◽  
Isurus Oxyrinchus ◽  
Males And Females ◽  
North And South ◽  
Tuna Longline

Tuna longline effort declined from 23—26 million hooks per year in 1979mdash;82 to 2mdash;4 million hooks per year in 1995mdash;98. Scientific observer coverage averaged 7.5%since 1988mdash;89, but increased in 1992mdash;93 (mean 23%). Observed catch per unit effort (CPUE) and the numbers of hooks set were used to estimate shark catches. Between 1988mdash;89 and 1997mdash;98,about 450 000 blue sharks (Prionace glauca), 65 000 porbeagles (Lamna nasus ) and 25 000 shortfin makos (Isurus oxyrinchus) were caught. In 1997mdash;98,about 45 000 blue sharks, 4000 porbeagles and 3000 makos were caught. Corresponding weight estimates were 1400 t, 150 t and 200 t. CPUE varied between foreign and domestic vessels, between north and south regions and among years, but there were no consistent temporal trends. Most males and females were immature, and most sharks were alive when recovered. Most sharks were processed, but usually only the fins were retained. The New Zealand tuna longline fishery is probably not seriously affecting pelagic shark stocks, but adequate assessment is not currently feasible. Accurate monitoring of Pacific Ocean catches is an important first step towards ensuring sustainability of their populations.

scholarly journals Distribution and trend in abundance of the porbeagle (Lamna nasus) in the southern hemisphere

2013 ◽  
Vol 64 (6) ◽  
pp. 518 ◽  
Author(s):  
Yasuko Semba ◽  
Kotaro Yokawa ◽  
Hiroaki Matsunaga ◽  
Hiroshi Shono
Keyword(s):  
Southern Hemisphere ◽  
Longline Fishery ◽  
Effective Management ◽  
Catch Per Unit Effort ◽  
Limited Region ◽  
Cape Of Good Hope ◽  
Tasman Sea ◽  
The Indian Ocean ◽  
By Catch ◽  
Tuna Longline

Knowledge of a species’ distribution is an important element in its effective management and conservation. The porbeagle (Lamna nasus) is a common by-catch shark in the tuna longline fishery in the southern hemisphere, but its distribution and abundance are largely unknown. The investigation of observer data from the tuna longline fishery and other fishery survey data has revealed that (1) porbeagles are distributed in the pelagic waters across the oceans of the southern hemisphere, (2) juveniles and adults are distributed in cooler environments than are neonates, (3) pregnant females occur in the pelagic waters of the Indian Ocean and the Tasman Sea, most being frequently recorded around the Cape of Good Hope between June and July and (4) the standardised catch per unit effort (CPUE) based on tuna longline fishery (1994–2011) and driftnet survey (1982–1990) data indicate no continuous decreasing trend in the abundance of the southern porbeagle, contrary to the declining trend reported in a limited region in the South Atlantic. Considering its circumglobal distribution, stock status of this population should be assessed using information from the areas of its major distribution, including pelagic waters, and international coordination across oceans is necessary for the effective management of this population.

scholarly journals JENIS DAN DISTRIBUSI UKURAN IKAN HASIL TANGKAP SAMPINGAN (BY CATCH) RAWAI TUNA YANG DIDARATKAN DI PELABUHAN BENOA BALI

2017 ◽  
Vol 5 (4) ◽  
pp. 453-460
Author(s):  
Skar Puji Astuti ◽  
Abdul Ghofar ◽  
Suradi Wijaya Saputra ◽  
Budi Nugraha
Keyword(s):  
Thunnus Albacares ◽  
Distribution Analysis ◽  
Target Species ◽  
Catch Per Unit Effort ◽  
Prionace Glauca ◽  
Thunnus Obesus ◽  
Southern Bluefin Tuna ◽  
By Catch ◽  
Research Show ◽  
Tuna Longline

ABSTRAK Hasil tangkapan rawai tuna terdiri dari dua jenis yaitu hasil tangkapan utama (target species) dan hasil tangkapan sampingan (by catch). Penelitian ini bertujuan untuk mendapatkan informasi jenis ikan hasil tangkapan utama dan ikan hasil tangkapan sampingan rawai tuna, menghitung komposisi ikan, menganalisa distribusi ukuran ikan dan mengetahui nilai CPUE ikan HTU dan ikan HTS. Penelitian dilaksanakan pada bulan April-Mei 2016 dengan mengikuti kegiatan sampling enumerator Loka Penelitian Perikanan Tuna Benoa, Bali. Hasil penelitian menunjukkan jenis ikan hasil tangkapan utama rawai tuna yaitu ikan Tuna mata besar (Thunnus obesus), Tuna sirip kuning (Thunnus albacares), Tuna sirip biru selatan (Thunnus maccoyii) dan Tuna albakora (Thunnus allalunga). Jenis ikan hasil tangkapan sampingan rawai tuna yang mendominasi yaitu ikan opah (Lampris guttatus), hiu air (Prionace glauca) dan escolar (Lepidocybium flavobrunneum). Perbandingan komposisi ikan hasil tangkapan utama yaitu 69% dan ikan by catch 31%. Distribusi ukuran ikan hasil tangkapan sampingan sebagian besar sudah memenuhi kriteria ikan layak tangkap. CPUE ikan hasil tangkapan sampingan lebih rendah dibandingkan dengan ikan hasil tangkapan utama. Kata kunci: Hasil Tangkapan Sampingan (by catch), Rawai Tuna, Pelabuhan Benoa Bali, Samudera Hndia.  ABSTRACT Catch of Tuna longline has two types, that is target species and by catch product. This research aims to determine the information type of target species and species by catch, calculate the composition of the fish, size of distribution analysis and determine the CPUE (Catch per unit effort) of species by catch and target species. This research is conducted in April-May 2016 following the sampling enumerator activities of Benoa port. The results of the research show that the type of target species Tuna Longline there are Big eye tuna (Thunnus obesus), Yellow fin tuna (Thunnus albacares), Southern bluefin tuna (Thunnus maccoyii) and Albakora (Thunnus allalunga). The types of species by catch Tuna Longline dominates that is Opah (Lampris guttatus), Shark (Prionace glauca) and Escolar (Lepidocybium flavobrunneum). Comparison of the composition target species is 69% and species by catch is  31%. The size distribution of species by catch already most the criteria of decent fish caught. CPUE of species by catch was lower than. Keywords: bycatch, tuna longline, benoa port, indian Ocean

Trophic overlap between blue sharks (Prionace glauca) and shortfin makos (Isurus oxyrinchus): Trophic linkages between two shark species in the Eastern Pacific Ocean food web

Food Webs ◽  
2016 ◽  
Vol 7 ◽  
pp. 13-19 ◽  
Author(s):  
Claudia Ivette Maya Meneses ◽  
Yassir Edén Torres Rojas ◽  
Felipe Galván Magaña ◽  
Sergio Aguiñiga García ◽  
Lizeth Daniela Trasviña Carrillo
Keyword(s):  
Pacific Ocean ◽  
Food Web ◽  
Eastern Pacific ◽  
Shark Species ◽  
Eastern Pacific Ocean ◽  
Prionace Glauca ◽  
Isurus Oxyrinchus ◽  
Trophic Overlap ◽  
Trophic Linkages

Studies of Ptiliidae (Coleoptera) in the Spirit Collection of the Natural History Museum, London 2: New species and records from P. Hammond's visit to New Zealand in 1983–84

2018 ◽  
Vol 154 (3) ◽  
pp. 179-196
Author(s):  
Michael Darby
Keyword(s):  
New Species ◽  
New Zealand ◽  
Natural History ◽  
Natural History Museum ◽  
History Museum ◽  
The North ◽  
Three New Species ◽  
North And South

Some 2,000 Ptiliidae collected in the North and South Islands of New Zealand in 1983/1984 by Peter Hammond of the Natural History Museum, London, are determined to 34 species, four of which are new to the country. As there are very few previous records, most from the Auckland district of North Island, the Hammond collection provides much new distributional data. The three new species: Nellosana insperatus sp. n., Notoptenidium flavum sp. n., and Notoptenidium johnsoni sp. n., are described and figured; the genus Ptiliodes is moved from Acrotrichinae to Ptiliinae, and Ptenidium formicetorum Kraatz recorded as a new introduction. Information is provided to aid separation of the new species from those previously recorded.

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