Urchin

The keystone species, is a phenomenon in which a certain species keep the proportion of an ecosystem in check. Sea otters, are a great example of a keystone species. Because, they keep sea urchins from consuming and destroying large kelp fields. If the otters were to disappear urchins would thrive and valuable kelp fields would be…

There are two major trophic cascades that scientist use. One is called bottom-up and the other is top-down. The controller of top-down would be the top predator or the apex predator (Wallach and O’Neill, 2009). The apex predator can also be known as the keystone species in that ecosystem. Top-down control is when the apex predator regulates the structure and population of the ecosystem (Wallach and O’Neill, 2009). The apex predators will prey on the consumers, which keeps the consumers…

Edward Dreisch was the the first scientist that demonstrated artificial “ embryo twinning”. Dreisch realized if he shook a embryo of a sea urchin he could separate them and make two sea urchins. In this experiment he showed that each cell in its early stage in the embryo has its own complete set of genetic instructions that can grow into a full organism. The sea urchins both grew and lived. Scientist soon became fully aware of the whole “embryo twinning” and started doing their own evaluations…

A keystone species play a far more important role than it’s relative abundance suggests. These species are the center pieces of their given communities and without them their ecosystem and habitat will fall apart. Keystones species are generally found in low numbers are often apex predators that control distribution and population, but are not limited to food sources, mutualistic species, and different providers. Some of these species are even ecosystem engineers that create or maintain habitats…

textbook describes how when no sources exist to control the number of urchins in the ocean, they devour kelp to such an extent that entire regions of seafloor become barren (Open Learning Initiative, 2015, p.246). Furthermore, scientists discovered that in areas populated by sea otters, kelp forests thrived as sea otters would dine on the urchins and would drop their empty shells onto the sea floor thereby frightening away urchins from the region (Open Learning Initiative, 2015, p.246). This…

This reduction of the Kelp forest would increase the atmospheric carbon in the coastal ecosystem. Being the top predator for sea urchins, without the sea otters, the kelp forests would be greatly reduced due to the main herbivore, sea urchins. These grazing animals can destroy kelp forests and consequently the wide diversity of animals that depend upon kelp habitat for survival. This relationship between sea otters and kelp is critical…

depth between July and August 2011 and showed that the creature experiences high mortality rates when in decreased pH waters (Chan 956). The lineage of larval urchins is affected by the release of buds. This is because of the increase in larval density causing the release of buds to result in higher larval mortality rates. Also, larval urchins go under plasticity when exposed to reduced pH. Results of the experiment stated that exposure to reduced pH had negative impacts on larval echinoderms…

Introduction: Due to human’s history of adverse interference, the livelihood of the normally abundant Australian Sea Lion has been affected. It is a pinniped animal, belonging to the genus Neophoca and the species cinerea.. Within this report there will be discussion of why Australian Sea Lions are considered a keystone species, including what their role is in resourcing, dominating, as well as maintaining the ecosystem they populate; scenarios of what would happen if they went extinct; how…

marine invertebrate such as sea urchins, clams, mussels, and snails, and their food resources are abundant. Current threats to southern sea otters include infectious diseases, contaminants, oil spills, fisheries interactions, predators, boat strikes…

“It is estimated that the worldwide population of sea otters once numbered between several hundred thousand to over one million before being nearly hunted to extinction by fur traders in the 1700s and 1800s” (Defenders of Wildlife). There are only approximately 106,000 sea otters left. Due to fur trade in the early 1900s, there was once under 2,000 sea otters worldwide. Sea otters can possibly be represented as a poster child for reintroduction yet they still remain on the endangered list. There…