The Falkland Islands marine ecosystem: A review of the seasonal dynamics and trophic interactions across the food web

Unveiling the wasp-waist structure of the Falkland shelf ecosystem: the role of Doryteuthis gahi as a keystone species and its trophic influences

“…This share is less than that with predatory/omnivorous species, suggesting that adult M. gregaria are a more important food source for benthic omnivorous species (Brickle et al ., 2003; Arkhipkin et al ., 2008) than for predatory/omnivorous species, sharing the same benthic habitat. Additionally, benthic omnivorous (skates) had the least niche overlap with zooplankton and vice versa, which indicates that skates feed little on pelagic zooplankton, even though previous studies found euphausiids and amphipods in the diet of skates (Brickle et al ., 2003; van der Grient et al ., 2023).…”

“…In the case of species showing higher TLs in Ecopath compared to stable isotope analysis, diet studies might have been biased or did not reflect the diet at time of sampling. These deviations might be caused by seasonal factors, opportunism, digestibility of prey, and ontogenetic changes (van der Grient et al ., 2023). Moreover, there might be cases with single species not sharing the same diet as other species belonging to the same functional group, which is a lost detail because of the averaging within a functional group.…”

“…There are many predatory species in the Patagonian Shelf LME, including piscivorous fish species such as hakes, red cod and kingclip, skate and shark species (Arkhipkin et al ., 2012). Other relevant predators are three pinniped species, several baleen and toothed whale species, dolphins, five penguin species and many other seabird species (van der Grient et al ., 2023). Despite the high productivity of the Patagonian Shelf LME, many of the higher TL consumers display migratory behaviour, with differences between the location of feeding and spawning grounds (van der Grient et al ., 2023).…”

“…The Falkland Shelf ecosystem is a part of the Patagonian Shelf LME and is characterized by tidal mixing and western boundary current fronts (Belkin et al ., 2009). It features high productivity due to upwelling of the cold Falkland Current originating in the Southern Ocean (Vivier and Provost, 1999; Agnew, 2002; Belkin et al ., 2009; Matano et al ., 2010; Gil et al ., 2018; van der Grient et al ., 2023). As with many other upwelling ecosystems, the Falkland Shelf is considered to have a wasp-waist structure with only a few species in intermediate trophic positions (e.g.…”

“…Therefore, the Falkland Shelf is a unique ecosystem, also given its high biomass of higher trophic-level animals, which also attract numerous fisheries. A high number of predatory species migrate from their spawning grounds in Argentine waters towards the waters around the Falkland Islands (Arkhipkin et al ., 2012; van der Grient et al ., 2023) to feed upon mid-level resident species that are highly abundant e.g. P. ramsayi and D. (formerly Loligo ) gahi .…”