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In order to assess feeding habits and trophic level of this species, we analysed the stomach content of 189 specimens collected
monthly in the southern Tyrrhenian Sea (central Mediterranean Sea). The results showed that this species is a pelagic predator
focusing on paralepidid fish and, more in detail, on two species such as Paralepis speciosa and...
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... order to study the feeding habits of albacore, a total of 189 individuals with a fork length (FL) comprised between 38.9 and 102.1 cm were caught between April 2005 and October 2006 off the north-eastern coast of Sicily (southern Tyrrhenian Sea) (Fig. ...
Context 2
... that use pooled data (%N and %W). Among teleosts, the most representative species in terms of %MW and %MN were P. coregonoides and P. speciosa (Table 1) followed by Sardina pilchardus. Among mol- luscs, exclusively represented by cephalopods Teuthida and Sepiolida, the dominant species according to both indices were H. dispar and Illex coindettii (Fig. 3, Table ...
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Citations
... Estas especies son depredadores oportunistas y se alimentan de una gran diversidad de presas. Las dietas del bonito y la albacora han sido descritas en diferentes partes del mundo (Consoli et al., 2008;Young et al., 2010;Varghese et al., 2014;Varela et al., 2017), pero aún hay un número limitado de estudios sobre sus hábitos alimentarios. Pocos trabajos se han concentrado en los cambios en su dieta con respecto a las temporadas climáticas (García y Posada, 2013). ...
... These species are opportunistic predators and eat a great diversity of prey. The diet of the little tunny and the albacora has been described in different parts of the world (Consoli et al., 2008;Young et al., 2010;Varghese et al., 2014;Varela et al., 2017), but there is still a limited number of studies on their feeding habits, and few works have focused on the changes in their diet with respect to climatic seasons (García and Posada, 2013). In general, these fish feed mainly on crustaceans, fish, and cephalopods. ...
... Estos fueron la presa más numerosa (26 %) en el contenido estomacal de T. albacares (Potier et al., 2007). Los peces son la presa principal en la mayoría de estudios sobre atún y otras especies pelágicas grandes, pues suministran un mayor enriquecimiento nutricional (Potier et al., 2007;Consoli et al., 2008). Es necesario resaltar la importancia de las larvas de invertebrados en la dieta de estos atunes; se encuentran con frecuencia y en gran abundancia, si bien su aporte energético es menor en comparación con otros organismos como peces o Cephalopoda. ...
The feeding habits of the bonito Euthynnus alletteratus and the albacore Thunnus alalunga were assessed by analyzing the contents of 85 stomachs (50 from bonito and 35 from albacore) collected between March 2018 and April 2019. A qualitative and quantitative analysis of the prey found in the stomach contents was conducted, as well as of the trophic spectrum between species and climatic seasons.
Climatic information was obtained through satellite images, analyzing variables such as sea surface temperature, salinity, and winds. In terms of abundance, the most representative prey were the fish Sardinella aurita (42.48 %) and Teleostei remains (27.45 %) for E. alletteratus, and Megalopa larvae (56.89 %) and Teleostei remains (10.26 %) for T. alalunga. The relative importance index indicates that the main prey for E. alletteratus were Teleostei remains (IRI = 1460.65) and Sardinella aurita (IRI = 1179.70), while, for T. alalunga they were megalopa larvae (IRI = 1367.19) and Teleostei remains (IRI = 840.94). These large pelagic predators were classified as generalists, with a low prey diversity in their stomach content. No trophic overlap was observed between the two species.
... Trait information was rarely used in an explanatory capacity in the North Pacific, North Atlantic and Mediterranean. Most studies from the North Atlantic and Mediterranean, home to some of the earliest and most detailed investigations of albacore diets (especially from the 1930's; Bouxin & Legendre, 1936;Legendre, 1934Legendre, , 1940, categorised the diets of albacore as 'specialised' (Consoli et al., 2008), of narrow trophic niche width (Teffer et al., 2015), and of short food chain length and low trophic adaptability (Pethybridge et al., 2018) compared to the longer food chain lengths and higher trophic complexity of Pacific tuna diets. Our re-analysis of the same data substantiates earlier observations and found that three trait guilds, (Brown et al., 2014). ...
Simplifying complex species interactions can facilitate tracking and predicting functional responses to ecological stressors. This is important for highly migratory pelagic predators, exploiting diverse prey fields as they respond to dynamic environments. We reconstructed the historical resource use of albacore tuna ( Thunnus alalunga ) globally from the 1900s to 2015 and confirmed highly biodiverse diets with 308 prey species, and an additional 238 taxa at coarser taxonomic resolution. We synthesised prey diversity into seven functional trait guilds using hierarchical divisive clustering algorithms as a function of four traits that describe habitat use and influence predator–prey encounter rates – prey habitat association vertically in the water column, horizontally along the coastal to pelagic gradient, seasonal and diel vertical migratory behaviour. We explored variability in historical composition of albacore diets across geographies based on species identity, individual trait information and functional trait guilds using a multi‐matrix modelling framework. Taxonomic information remains important for trophic ecology, however, species‐based diet composition in albacore tuna was highly variable across geographies and years sampled, making interpretation of these patterns difficult. By simplifying species identity into habitat‐based traits, we highlight changes in prey resources consumed, such as the historical importance of near‐surface epipelagic prey resources from coastal to oceanic habitats, and seasonally migrating continental shelf prey, with less frequent pulses of deeper water and demersal taxa. Trait information and trait guilds serve as useful classification frameworks for identifying functionally redundant food web linkages across biodiverse prey, and will prove useful in tracking predators' foraging responses to changing resource availability.
... Information on lunar phase (new moon, waxing crescent, first quarter, waxing gibbous, full moon, waning gibbous, third quarter, waning crescent) was assigned to each collected sample. Because of the short time scale of lunar phases (on the order of days) and the potential for hard parts to persist in predator guts for longer time scales, we established a cutoff in degree of digestion, excluding prey completely digested, i.e., when only hard parts without flesh remains were found [25,46,47]. Mesopelagic prey items were counted (each individual prey) and measured to the lowest 0.1 mm, recording the standard length (SL) for fish and mantle length (ML) for cephalopods. ...
The influence of the lunar cycle on bluefin tuna foraging in the upwelling area of the Strait of Messina was investigated by exploring trophic interaction with mesopelagic fish and cephalopod prey. To focus on how the lunar cycle could affect availability of mesopelagic prey for this predator, we tested potential differences in the diet related to each lunar phase. Moreover, we considered two potential impacts of the lunar cycle: the lunar irradiance and the strength of currents. Overall, 2672 prey items were mesopelagic fish and cephalopods, representing 60.7% of overall diet by number. The main mesopelagic fish prey items were lanternfishes and dragonfishes, while Onychoteuthis banksii was the most important cephalopod prey. In summary, the Strait of Messina has highly specific hydrodynamic and biological features which strongly depend on upwelling currents, which in turn are influenced by the lunar cycle (new and full moon with strong currents, quarters with fewer currents). Upwelling causes water mixing, bringing to the surface a large amount of mesopelagic fauna which become more readily available to tuna. Lunar irradiance contributes to the variation of prey composition, increasing the success of visual predation on mesopelagic resources at high light in the water column.
... During this daytime period, the need to maintain a high body temperature guides these animals to ascend to surface waters, while the greater probability of finding prey in deep/cold waters offsets the disadvantageous metabolic cost of remaining near the deep (Stephens and Krebs, 2019). However, it is plausible that even when rising to the epipelagic zone during the day for body warming, the chances of foraging during the ascent are smaller; even more so knowing that swordfish, blue shark, and albacore tuna feed largely on mesopelagic cephalopods, fish, and crustaceans (Young et al., 2006;Consoli et al., 2008;Vaske-Jr et al., 2009). Additionally, the study by Vedor et al. (2021) seems to conflict with the abovementioned pattern, in that tagging results indicated that vertical migrations of blue sharks are more related to optimizing foraging than to thermoregulation. ...
Sustainable fisheries' managers increasingly seek to implement measures that reduce the mortality of threatened species while maintaining or increasing catch of target species. Our study proposed a simple management option for optimizing fishing over daily and seasonal scales to maximize catch success while protecting non-target species in pelagic longline fisheries. We used Bayesian beta mixed regression models to describe the effects of setting times and seasonality on catches in a pelagic longline fishery in the southwest South Atlantic Ocean (SWAO). Targeted species (swordfish, blue shark, and albacore tuna) are typically captured in fully nocturnal sets (started between 16 and 00 h), whereas shortfin mako shark and loggerhead turtles are typically captured during partially nocturnal sets (started between 00 and 04 h); probably a response to hook depth and circadian behaviours. The results suggest that it is feasible to use only fully nocturnal sets to target preferred species while reducing incidental catch of non-target species. The catch of target species was higher in austral winter, explained by the northward displacement of the subtropical convergence in the SWAO during this season. These results provide a baseline for bycatch mitigation strategies in pelagic longline fisheries at regional and global scales.
... Studies conducted in the northeast Atlantic, the Bay of Biscay, and the Tyrrhenian Sea (central Mediterranean) reported that ALB diet was mainly composed of fishes, followed by crustaceans and cephalopods (Hassani et al. 1997;Pusineri et al. 2005;Consoli et al. 2008). Ortiz de Zárate (1987), Consoli et al. (2008), andGoñi et al. (2011) showed that the European anchovy was a major prey of ALB in the Bay of Biscay. ...
... Studies conducted in the northeast Atlantic, the Bay of Biscay, and the Tyrrhenian Sea (central Mediterranean) reported that ALB diet was mainly composed of fishes, followed by crustaceans and cephalopods (Hassani et al. 1997;Pusineri et al. 2005;Consoli et al. 2008). Ortiz de Zárate (1987), Consoli et al. (2008), andGoñi et al. (2011) showed that the European anchovy was a major prey of ALB in the Bay of Biscay. In contrast, Pusineri et al. (2005) did not find anchovy in the diet of ALB from the Bay of Biscay. ...
This study presents information about trophic relationships between juvenile albacore (ALB, Thunnus alalunga) and skipjack tuna (SKJ, Katsuwonus pelamis) in the Gulf of Cadiz (East Atlantic Ocean). Data on stomach contents (SCA) and stable isotope ratios of carbon and nitrogen (SIA) were analyzed to ascertain foraging patterns and trophic niche breadths and overlapping. SCA showed that European anchovy (Engraulis encrasicolus) and Atlantic chub mackerel (Scomber colias) were the most important prey species in both tuna species. A PERMANOVA analysis of the SCA data revealed interspecific differences in the diet (p < 0.05). δ15N and δ13C values from ALB muscle and liver tissues were higher than those from SKJ samples. As with SCA, the PERMANOVA analysis of isotopic data indicated significant interspecific differences in both muscle and liver samples (p < 0.01). Isotopic trophic niche values estimated by Bayesian standard ellipse corrected areas (SEAC) showed low (muscle) or no (liver) overlap between ALB and SKJ. Taken together, the present results suggest that, although juveniles of the two species fed for an extended period of time in the same area and shared some prey species, there is evidence of food resource partitioning, thus preventing trophic competition.
... Based on the principle of biomagnification (Gray 2002), one of the most plausible hypothesis that support such pattern may be the fact that T. alalunga occupied a slightly higher trophic level than K. pelamis (based on the δ 15 N signatures). Probably, the higher trophic level of T. alalunga is related to its mostly piscivorous diet (Consoli et al. 2008) vs. the Fig. 2 Hg, Cd, and Pb concentrations by species and sex (left panels A-C) and the partial mean effect (error bars are 95% confidence intervals) of the factor species on Hg, Cd, and Pb concentration (right panels D-F) Environ Sci Pollut Res opportunistic diet usually based on invertebrates (crustaceans and cephalopods) conducted by K. pelamis (Varela et al. 2019). ...
... For the central North Pacific Ocean, Choy et al. (2009) reported potential preys to large-pelagic predators that inhabit epipelagic stratum display lower Hg concentrations (0.0091 ± 0.0108 mg·kg -1 ww) than the species from the upper mesopelagic stratum (0.0406 ± 0.0601 mg·kg -1 ww). Therefore, the deeper-ranging of predation conducted by T. alalunga (0-500 m depth; Consoli et al. 2008) in comparison with the shallower one reached by K. pelamis (0-300 m depth; Schaefer and Fuller 2007) potentially increases its probability exposure to this toxic metal. In fact, the averaged methylmercury for the T. alalunga foraging range presents a higher concertation (0.1228 pmol L -1 ) than the concertation (0.0968 pmol L -1 ) at the shallower range of K. pelamis in Mediterranean waters (Cossa et al. 2009). ...
Albacore Thunnus alalunga and skipjack tuna Katsuwonus pelamis are highly migratory species that are usually caught together in the Western Mediterranean. These species are top predators that are highly affected by the biomagnification process through the trophic chain. Bioaccumulation pattern of the main metal pollutants (mercury, Hg; lead, Pb; and cadmium, Cd) were analyzed in muscle tissues of 52 individuals (26 T. alalunga and 26 K. pelamis) of these highly consumed species in order to address two objectives: (1) compare the species-specific bioaccumulation between these large-pelagic species, and (2) assess the healthy properties of such valuable resources based on the trace metal limits established by the European Commission Regulation (ECR). Both generalized linear mixed models and redundancy analysis indicated a differential bioaccumulation between these two tuna species. While T. alalunga accumulates higher concentrations of Hg (0.1996 ± 0.0602 mg·kg-1 weight wet-ww), K. pelamis accumulates higher concentrations of Cd (0.0076 ± 0.0049 mg·kg-1 ww) and Pb (0.0031 ± 0.0017 mg·kg-1 ww). Size and trophic ecology support the differences detected in the bioaccumulation pattern. Heavy metal concentrations were below the tolerable limits considered by ECR (1, 0.1, and 0.3 mg·kg-1 ww for Hg, Cd, and Pb, respectively).
... The few studies conducted in the Mediterranean Sea show that adults feed on cephalopods (Bello, 1999;), fishes (Consoli et al., 2008) and crustaceans (Goñi et al., 2011). However, most of these studies were based on limited sample sizes and a low number of nonempty stomachs, probably because animals were caught at night when feeding activity is low (Aloncle & Delaporte, 1973;Watanabe et al., 2004;Young et al., 2010). ...
... Similarly, paralepids are identified as the main fish prey in terms of biomass for albacore tuna in two other areas of the Mediterranean Sea (Tyrrhenian and Adriatic Seas) (Consoli et al., 2008;Goñi et al., 2011). By contrast, in the north-east Atlantic Ocean and the western tropical Indian Ocean, epipelagic and reef-associated fishes, rather than mesopelagic fishes, are the main food source for albacore tuna (Goñi et al., 2011;Romanov et al., 2020). ...
... Tunas are recognized as opportunistic predators that feed on a broad spectrum of prey. Reproductively active albacore caught in the western Mediterranean Sea foraged on a broad spectrum of prey (63) This result is in line with the feeding strategy of albacore of the central Mediterranean Sea (Consoli et al., 2008). Similarly, previous studies conducted on other temperate waters described a feeding strategy based on a few prey that accounted for a large proportion of their diet (Glaser et al., 2015;Goñi et al., 2011;Pinkas et al., 1971;Pusineri et al., 2008;Watanabe et al., 2004). ...
Mature albacore tuna (Thunnus alalunga) are expected to have high energy requirements at the time of breeding. However, there are no descriptions of the diet of albacore in the Mediterranean Sea that can help us to understand if such requirements can be obtained from feeding during reproduction. In this study, we analysed the stomach contents of reproductively active albacore captured from 2010 to 2015 in the oligotrophic waters of the western Mediterranean Sea, one of their main spawning grounds. Estimates of stomach fullness revealed intense feeding activity, and prey composition indicated important consumption of mesopelagic fish, including barracudinas, myctophids and small pelagic crustaceans. Plastic debris occurred in 25%–53% of the stomachs sampled across all years. Prey composition was not different between males and females. However, females fed at higher rates and had higher hepatosomatic index values than males, suggesting that increased feeding could contribute to meet their higher energy demand associated with offspring production. We observed a diet shift from small crustaceans to fish prey along fish size. During the spawning period, albacore showed a specialist feeding behaviour by preying on aggregations of vertically migrating myctophids and small crustaceans, probably when they were near the surface. This study provides information and biological data to support ecosystem modelling and to increase the understanding of albacore ecology.
... Indeed, this unique habit of swimming characterizes species of barracudina (Whitehead et al., 1984), which explains, together with their slender form, this mono-species entrapment events. We postulate that this unique swimming behavior contributes to their known tendency to efficiently avoid sampling nets, which is eventually reflected in a scarce and infrequent information available throughout their distribution, that is mainly based on documenting juvenile and adult specimens inside stomachs of large pelagic fishes (Potier et al., 2007;Consoli et al., 2008;Battaglia et al., 2013). Moreover, the absence of juvenile individuals in the traps throughout the year may suggest they either lack vertical swimming abilities at this life stage or that they simply do not dwell in this layer of the pelagic water column. ...
This study documents an active penetration of a large school of Sharpchin Barracudina Paralepis coregonoides into pelagic, open-sea sediment traps in the SE Levantine basin of the SE Mediterranean Sea. The sediment traps at 180 and 280 m depth were deployed on the DeepLev mooring, ~50 km offshore Israel, at 1500 m water depth. Over one year of deployment (November 2016 till December 2017), the fish have repeatedly invaded the automated, time-series (11-12 days) sediment traps with 25 mm baffler mesh and ended up in the collecting bottles (up to 42 fish per bottle) that contained formaldehyde, thus preserving them for observation and analysis. No other fish species were captured in the traps. This undesirable catch of such an elusive and understudied species provides a unique opportunity to understand its biogeography in particular, and to enhance our knowledge of the biodiversity in the remote, and relatively inaccessible, mesopelagic habitat. Low mitochondrial genetic divergence found between specimens from this study and previously published data from distant localities around the Atlantic Ocean signify high migratory habits throughout the biogeographic distribution. The continuous entrapment throughout the year and the sexually mature individuals indicates that this species is more common than was expected in SE Levantine basin. The installation of a stainless-steel mesh (7mm) on the conventional sediment trap openings should therefore be considered when planning a large-scale scientific campaign in the pelagic SE Mediterranean and probably elsewhere.
... In this study we have focused on representative key species from the Mediterranean pelagic ecosystem since recent reports from other latitudes have shown that TBBPA exposed pelagic species were more prone to experience biomagnification than demersal fish (Choo et al., 2019). In the Mediterranean Sea, the two small pelagic fish feed mostly on C. typicus (Costalago et al., 2014), and the tunid diet contains sardine and anchovy (Consoli et al., 2008;Navarro et al., 2017). In addition to uptake from water (Choo et al., 2019;Gu et al., 2017), food transfer of this chemical is likely to occur as all marine organisms have been reported to accumulate TBBPA to a certain extend. ...
Tetrabromobisphenol A (TBBPA), a brominated flame retardant used in synthetic polymers and electronics, is present in the aquatic environment and recent evidence suggests it can be potentially biomagnified in the marine ecosystem. However, the toxicity of TBBPA in the marine biota has not been investigated in detail. In this study we aimed to understand the role of carboxylesterases (CEs) in xenobiotic metabolism under the exposure of marine organisms to a chemical of environmental concern, TBBPA. Specifically, we tested for in vitro inhibition of CE activity in a range of marine organisms covering different ecological niches, from species from low (mussels and copepods), medium (sardines and anchovies) and high trophic levels (tuna). The results revealed that the highest inhibition of CE activity to 100 μM TBBPA was recorded in mussels (66.5% inhibition) and tunids (36.3-76.4%), whereas copepods and small pelagic fish showed comparatively lower effects (respectively, 30% and 36.5-55.6%). Our results suggest that CE-mediated detoxification and physiological processes could be compromised in TBBPA-exposed organisms and could ultimately affect humans as many of them are market species.
... These results may be attributed to the short period of time when the samples were collected and/or the predominance of a few species in Alboran food web. It is worth to note that a narrow niche width was also reported for other large pelagic fishes inhabiting the Mediterranean Sea, such as albacore, Thunnus alalunga, spiny dogfish, Squalus acanthias, and Mediterranean spearfish, Tetrapturus belone (Consoli et al., 2008;Gračan et al., 2017;Castriota et al., 2008). ...
The Alboran Sea holds one of the highest biological productivity rates in the Mediterranean, and thus represents an important nursing area for pelagic fishes including tunas. Trophic interactions between sympatric populations of age-0 bluefin tuna (ABFT) and Atlantic bonito (BON) were investigated in Alboran by integrating stomach content analysis (SCA) and stable isotope analysis of bulk muscle (BSIA) and individual amino acids (AA-CSIA). BON and ABFT individuals were collected in the Bay of Malaga; additionally, ABFT were caught off Carboneras. SCA showed that BON fed only on teleost fishes, whereas ABFT diet also comprised invertebrates. We found significant dietary differences between groups using SCA and BSIA data. Low values of niche width estimated from SCA and BSIA indicate poor dietary diversity in the two sampling sites. There was no isotopic niche overlap between groups, which may indicate resource partitioning. Trophic positions (TP) estimated from SCA, BSIA and AA-CSIA place BON at higher TP than ABFT.
