Still, trophic cascades have been observed in all biomes. Strength and type of effects vary because food chains naturally vary in length between ecosystems. Sometimes, predators reduce herbivores which increases plant abundance, but sometimes predators reduce plant abundance. 5/12
![Landscape-level effects of trophic cascades from five selected freshwater and marine ecosystems. (A) Shallow seafloor community at Amchitka Island (Aleutian archipelago) before (1971; photo credit: P. K. Dayton) and after (2009) the collapse of sea otter populations. Sea otters enhance kelp abundance (right) by limiting herbivorous sea urchins (left). (B) A plot in the rocky intertidal zone of central California before (September 2001, right) and after (August 2003, left) seastar (Pisaster ochraceous) exclusion. Pisaster increases species diversity by preventing competitive dominance of mussels. [Photo credits: D. Hart] (C) Long Lake (Michigan) with largemouth bass present (right) and experimentally removed (left). Bass indirectly reduce phytoplankton (thereby increasing water clarity) by limiting smaller zooplanktivorous fishes, thus causing zooplankton to increase and phytoplankton to decline. (D) Coral reef ecosystems of uninhabited Jarvis Island (right, unfished) and neighboring Kiritimati Island (left, with an active reef fishery). Fishing alters the patterns of predation and herbivory, leading to shifted benthic dynamics, with the competitive advantage of reef-building corals and coralline algae diminished in concert with removal of large fish. (E) Pools in Brier Creek, a prairie margin stream in south-central Oklahoma with (right) and lacking (left) largemouth and spotted bass. The predatory bass extirpate herbivorous minnows, promoting the growth of benthic algae.](https://cdn.bsky.app/img/feed_thumbnail/plain/did:plc:qrfsgkzpsekqmjgoydskikzl/bafkreic5pxmurehvvsq3rseb4htneczb6if4au52ih4sqtxvw7qk5j3ana)
