Search results for "Thunnus thynnu"

Unveiling the Relationship Between Sea Surface Hydrographic Patterns and Tuna Larval Distribution in the Central Mediterranean Sea

2021

Thunnus thynnus (Atlantic bluefin tuna, ABT) and other tuna species reproduce in the Mediterranean Sea during the summer period. Despite the Central Mediterranean Sea, the Strait of Sicily in particular, being a key spawning site for many tuna species, little is known on the effects of oceanographic variability on their larval distribution in this area. The abundance and presence-absence of larval specimens for three tuna species (ABT, bullet tuna and albacore) were modeled in order to examine their relationships with environmental factors, by analysing historical in situ information collected during seven annual surveys (2010–2016). The results revealed that most tuna larvae for the three …

Tracking multiple pathways of waste from a northern bluefin tuna farm in a marine-coastal area.

2011

Aquaculture of bluefin tuna in Mediterranean coastal waters has generated growing concern about the negative environmental effects. In the present isotopic study we examined the dispersal and fate of organic matter derived from a Mediterranean tuna farm in the surrounding environment. An overall enrichment in the heavy nitrogen isotope was found in the feed and in farmed tunas, indicating the input of isotopically traceable organic matter in the system. Waste was clearly traceable in the water column up to 1000 m from the cages, while only slight accumulation occurred in the sediment just below the cages. Waste was isotopically shown also to contribute to the diet of demersal and benthopela…

Ontogenetic shift in feeding habits and trophic levels of bluefin tuna (Thunnus thynnus) in Mediterranean

2007

Possible changes in diet and trophic levels in relation to size of Mediterranean bluefin tuna, Thunnus thynnus, were investigated using labelled carbon (d13C) and nitrogen (d15N) stable isotopes. Samples were obtained from two locations in the southern Tyrrhenian Sea (Western Mediterranean Sea) in May and October 2004. The d13C and d15N analyses revealed at least three significant isotopic groups [small juveniles (0.7– 2.2 kg), sub-adults (15–50 kg) and adults (70 to 225 kg)]. d13C was negatively dependent on weight, while d15N was positively dependent on weight [TW ¼ 8.2 (±0.16) + 0.03 (± 0.0) *d15N (n ¼ 49; r ¼ 0.91; P < 0.001)]. Different prey contribution to the diet was highlighted for…

Environmental Conditions along Tuna Larval Dispersion: Insights on the Spawning Habitat and Impact on Their Development Stages

2022

Estimated larval backward trajectories of three Tuna species, namely, Atlantic Bluefin Tuna (Thunnus thynnus, Linnaeus, 1758), Bullet Tuna (Auxis Rochei, Risso, 1801) and Albacore Tuna (Thunnus alalunga, Bonnaterre, 1788) in the central Mediterranean Sea, were used to characterize their spawning habitats, and to assess the impact of changes due to the major environmental parameters (i.e., sea surface temperature and chlorophyll-a concentration) on larval development during their advection by surface currents. We assumed that the environmental variability experienced by larvae along their paths may have influenced their development, also affecting their survival. Our results showed that the …

EFFECT OF SLAUGHTERING METHODS ON STRESS OF CAGED BLUEFIN TUNA (THUNNUS THYNNUS).

2007

Allevamento e qualità del prodotto. In “La stabulazione del tonno rosso mediterraneo (Thunnus thynnus) in Provincia di Trapani”

2009

Contaminanti chimici e microbiologici nel tonno

2009

Nitrogen stable isotopes as tracers of biodeposition from a tuna farm in the Western Mediterranean

2007

The dynamics of Italian competitive positioning in the Mediterranean Bluefin tuna industry

2020

The bluefin tuna or Thunnus thynnus is one of the widely recognised fish species since ancient times. Italy is the most important players in the international arena, however, the introduction of a system of total allowable catches and other measures established by the International Commission for the Conservation of Atlantic Tunas, has deeply changed the competitive positioning of Italy. The aim of this study is to perform an analysis of the comparative advantage of Italy by using the relative trade advantage index. Findings reveal that Italy has gained a competitive advantage in the Maltese market and has suffered a loss of the historical competitive advantage in the Japanese one. Results …

STUDY OF LARGE PELAGIC FISH LIFE-HISTORY TRAITS IN THE CENTRAL MEDITERRANEAN SEA AND PROJECTION UNDER FUTURE CLIMATE CHANGE SCENARIOS

2022

One of the most sensitive life periods for each species is the first life stages (larval and juvenile). The survival rates of pelagic fish larvae in these phases are usually very low and subject to fluctuations, consequently affecting the recruitment of new generations. From historical Tuna landing data, the stock's abundance is fluctuating, especially for Atlantic Bluefin Tuna (ABT) (Thunnus thynnus, Linnaeus, 1758) Eastern stock. It is the largest Mediterranean Tuna and one of the most expensive species in the world. Some studies hypothesized that the fluctuations are dictated by environmental factors, particularly in the early life stages. Therefore, it appears necessary to better unders…