Plot with stable carbon on the X-axis and stable nitrogen on the Y-axis, showing the difference in isotope values between predator (black-legged kittiwake) and prey (fish and invertebrates). Black-legged kittiwakes are in the middle of the plot, below Arctic cod.

After accounting for dietary discrimination, #δ13C and #δ15N #isotope values in kittiwake livers were at a lower #trophiclevel than Arctic cod.

What does this mean? While kittiwakes do consume Arctic cod (as seen in stomachs), stomach analysis may underestimate soft tissue prey, such as #inverts.

A scheme of the benthopelagic deep-sea food web of the South Sandwich Islands in the Southern Ocean. The image represents the daily vertical migration of small zooplankton (e.g. krill) and squids. Small zooplankton (trophic level 2) are eaten by squid and smaller crustaceans (e.g. shrimp) from the trophic level 3. Organisms in trophic level 3 are eaten either by larger squid and pelagic fish, or by demersal species such as crabs and fish (in trophic level 4). These are eaten by larger fish such as the toothfish (in trophic level 5). From the literature it is also in the image a potential 6th trophic level represented by a sperm whale and elephant seal that common feed in larger squid (from trophic level 4) and toothfish (from trophic level 5). It is also in the image a penguin sinking to the bottom of the ocean representing a different trophic link and a food source for deep sea organisms and frequently found in the stomachs of toothfish. The arrows have different colours representing pelagic links, demersal links, as well the transition from pelagic to demersal components and from the demersal to the pelagic component.

Check out our newest paper at @ecography.bsky.social on #DeepSea #FoodWebs at the #SouthernOcean 🧪🦑🇦🇶

We used #StableIsotopes to study the #benthopelagic food web at the #SouthSandwichIslands! We found a 5 #TrophicLevel web with #Toothfishes as #TopPredator 🐟🐙🦐🐧

@bas.ac.uk @ucoimbra.bsky.social