If exposure to a more acidic pH caused a decline in
some sea urchin populations, how might this affect the storage of carbon in ocean sediments?
Otters had kept
sea urchin populations down, but once their population was drastically reduced, urchins feasted on kelp to the point of over-consumption.
Without sea otters,
sea urchin populations eventually exploded and overgrazed the kelp, leaving behind large areas of «urchin barrens.»
Reintroduction of sea otters to British Columbia has led to a dramatic improvement in the health of coastal ecosystems, [143] and similar changes have been observed as sea otter populations recovered in the Aleutian and Commander Islands and the Big Sur coast of California [144] However, some kelp forest ecosystems in California have also thrived without sea otters, with
sea urchin populations apparently controlled by other factors.
[76] Reintroduction of sea otters to British Columbia has led to a dramatic improvement in the health of coastal ecosystems, [77] and similar changes have been observed as sea otter populations recovered in the Aleutian and Commander Islands and the Big Sur coast of California [65] However, some kelp forest ecosystems in California have also thrived without sea otters, with
sea urchin populations apparently controlled by other factors.
A new study suggests that an aggressive reef competitor — the Threespot Damselfish — may have impeded the recovery of Caribbean long - spined
sea urchin populations after a mysterious disease outbreak caused a massive die - off of these animals over three decades ago.
Not exact matches
Sea urchins and abalone, for example, have a harder time recovering from
population declines because their reproduction relies on broadcast spawning.
Wrasse consume many molluscs and crustaceans, and play a key role controlling
populations of
sea urchins that can deplete seafloor kelp forests — vital sanctuaries for many marine species including young cod.
For example just a small number of
sea otters can determine
urchin numbers, or a few grey wolves determine the size of bison, deer or elk
populations.
Quantitative fisheries ecology, fisheries ecosystem dynamics,
population dynamics modeling, fisheries stock assessment and management, trophic dynamics, Bayesian statistics, American and spiny lobsters, groundfish,
sea urchin, and
sea cucumber.
In a well - studied example from Alaskan kelp forests, [24]
sea otters (Enhydra lutris) control
populations of herbivorous
sea urchins through predation.
They keep the
population of certain benthic (
sea floor) herbivores, particularly
sea urchins, in check.
Today, California sheephead, spiny lobsters, and sunflower stars are the primary consumers of
sea urchins that help keep their
populations in check.
Due to the intact connectivity of the extensive seagrass beds, desnse mangrove forests, and robust coral reefs, the remoteness of the area, and the history of protection from coastal development, the Gardens of the Queen represents a «baseline» for a nearly pristine Caribbean marine ecosystem; an ecosystem that includes healthy
populations of apex predators like sharks and groupers, important grazers like Rainbow parrotfish and long - spine
sea urchins, and recovering endangered species like elkhorn coral and hawksbill
sea turtles.
Populations of parrotfish are a critical component of that herbivory, particularly since the decline of Diadema
sea urchins in the early 1980s; the main causes of mortality of parrotfish are the use of fishing techniques such as spearfishing and, particularly, the use of fish traps....