Figure 1.
Stable isotope ratios in the potential prey of apex predators from the northwestern Mediterranean.
Potential prey considered: pelagic crustaceans (solid squares), gelatinous plankton (empty squares), squid (solid triangles) and small pelagic and mesopelagic fish (empty triangles). Error bars show standard deviation.
Table 1.
Sample size and stable isotope ratios of pelagic prey and predators in the western Mediterranean Sea.
Figure 2.
Stable isotope ratios of bluefish, blueshark, leerfish, bonito, striped dolphins and neritic loggerhead sea turtles from the northwestern Mediterranean.
Solid circles represent the average stable isotope ratios of each consumer after correcting for diet-tissue isotopic discrimination and error bars show standard deviation. Other symbols show the average stable isotope ratios of potential prey: pelagic crustaceans (solid squares), gelatinous plankton (empty squares), squid (solid triangles) and small pelagic and mesopelagic fish (empty triangles).
Figure 3.
Stable isotope ratios of fin whales from the northwestern Mediterranean.
A solid circle represents the average stable isotope ratios of whales after correcting for diet-tissue isotopic discrimination and error bars show standard deviation. Other symbols show the average stable isotope ratios of potential prey: pelagic crustaceans (solid squares), gelatinous plankton (empty squares), squid (solid triangles) and small pelagic and mesopelagic fish (empty triangles).
Table 2.
Relative importance of gelatinous plankton in the diet of pelagic mesopredators and apex predators from the Mediterranean Sea, as revealed by stomach content analysis.
Figure 4.
Stable isotope ratios of bluefin tuna, little tunny, spearfish, and swordfish from the northwestern Mediterranean.
Solid circles represent the average stable isotope ratios of each consumer after correcting for diet-tissue isotopic discrimination and error bars show standard deviation. Other symbols show the average stable isotope ratios of potential prey: pelagic crustaceans (solid squares), gelatinous plankton (empty squares), squid (solid triangles) and small pelagic and mesopelagic fish (empty triangles).
Figure 5.
Feasible contribution of potential prey to the diet of bluefin tuna, little tunny, spearfish and swordfish according to SIAR.
Nekton 1: sardine. Nekton 2: anchovy, lanternfish, horse mackerel and longfin squid. Nekton 3: mackerel and shortfin squid. Results are shown as 95, 75 and 25% credibility intervals for each prey.
Figure 6.
Stable isotope ratios of oceanic loggerhead sea turtle and ocean sunfish from the northwestern Mediterranean and feasible contribution of potential prey to their diet according to SIAR.
Solid circles represent the average stable isotope ratios of each consumer after correcting for diet-tissue isotopic discrimination and error bars show standard deviation. Other symbols show the average stable isotope ratios of potential prey: pelagic crustaceans (solid squares), gelatinous plankton (empty squares), squid (solid triangles) and small pelagic and mesopelagic fish (empty triangles). Nekton: anchovy, lanternfish, horse mackerel and shortfin squid. Results are shown as 95, 75 and 25% credibility intervals for each prey.
Figure 7.
Stable isotope ratios of the diet of amberjack, pompano, horse mackerel, dolphinfish, blue butterfish and mackerel from the northwestern Mediterranean.
Solid circles represent the average stable isotope ratios of each consumer after correcting for diet-tissue isotopic discrimination and error bars show standard deviation. Other symbols show the average stable isotope ratios of their potential prey: pelagic crustaceans (solid squares), gelatinous plankton (empty squares), squid (solid triangles) and small pelagic and mesopelagic fish (empty triangles).
Figure 8.
Stable isotope ratios of albacore and bullet tuna from the northwestern Mediterranean and feasible contribution of potential prey to their diet according to SIAR.
Solid circles represent the average stable isotope ratios of each consumer after correcting for diet-tissue isotopic discrimination and error bars show standard deviation. Other symbols show the average stable isotope ratios of their potential prey: pelagic crustaceans (solid squares), gelatinous plankton (empty squares), squid (solid triangles) and small pelagic and mesopelagic fish (empty triangles). Nekton: anchovy, lanternfish, horse mackerel and shortfin squid. Results are shown as 95, 75 and 25% credibility intervals for each prey.
Figure 9.
Feasible contribution of potential prey to the diet of amberjack, pompano, horse mackerel, dolphinfish, blue butterfish and mackerel according to SIAR.
Nekton: anchovy, lanternfish, horse mackerel and longfin squid. Results are shown as 95, 75 and 25% credibility intervals for each prey.
Table 3.
Proximate chemical composition and energy density of four potential preys.