Some peculiarities in Patagonoian toothfish Dissostichus eleginoides (Nototheniidae) biology in the area of the Kerguelen Islands (Sub-Antarctica, Indian Ocean)

• Main Author: Pshenichnov, L.K.
• Other Authors: Yakovlev, V.N.
• Format: Other Non-Article Part of Journal/Newspaper
• Language: Russian
• Published: 1994
• Subjects: Patagonian toothfish; Feeding behaviour; Geographical distribution; Dissostichus eleginoides; Freezing trawlers; Food organisms; Species composition; Jellyfish; Vertical distribution; Fishing areas; Food availability; Патагонский клыкач; Географическое распределение; Пищевой рацион; Спектр питания; Сезонная динамика; Austral; Indian; Kerguelen; Kerguelen Islands; Southern Ocean; Южный Океан; Antarc*; Antarctica; Patagonian Toothfish
• Online Access: http://hdl.handle.net/1834/15805

Distribution and feeding habits of the Patagonian toothfish Dissostichus eleginoides from the Kerguelen Isles region (Southern Indian Ocean, France) in the summer season 1991-1992 are discussed. The studies based on the material collected by the author aboard freezing trawler Poltava. The fieldwork was done in the austral summer 1991-1992 (November-April) within the insular shelf and slope. The Patagonian toothfish feeding largely on fish and squid, but can switch prey to consume available food (Hyperiids), accessory (gelatinous organisms) or incidental such as bottom crustaceans, octopuses, food waste from the ships galley. There is a regular depth distribution pattern of size-segregated groups of the toothfish within one fishing area -- the larger fish occurring at greater depths. These size- and depth-segregated groups have also been observed to differ in their diet, there being differences in qualitative composition of their prey at different depths. Seasonal (summer) shift of the size-segregated groups to greater depths has been observed. The fish that were taken in April at depth 550-600 m were supposed to be of the groups that had occurred at depths of 350-400 m during December-April. Seasonal variation in food species composition of the Patagonian toothfish at depths of 500 to 600 m has been recognised. Cold water gelatinous organisms (Salpae, Ctenophora, Scyphomedusae) -- staple food for D. eleginoides during December to February were replaced by a natal-subtropical species of squid (Chiroteuthis veranyi). Патагонский клыкач, питаясь на промысловых участках в основном рыбой и кальмарами, при определенных условиях может переходить на питание более доступной (гиперииды), второстепенной (желетелые организмы) или случайной (донные ракообразные, осьминоги, отходы с судов) пищей. Выявлено закономерное прямое распределение размерных группировок клыкача по глубинам в пределах одного промыслового участка (северного) — более крупные (взрослые) особи обитают на больших глубинах. Также отмечено различие в спектре ...