The role of the sea otter (Enhydra lutris) as a keystone species has been studied for years. Studies have strongly discussed the function of this animal that, though few in number, have created large impacts in the ecosystem in which it inhabits. Their main choice of habitat lies in kelp forests due to the kelp’s effect on the reduction of wave action and their closeness to rocky shores which provide habitat for otter prey (Schiel and Foster, 2015). Sea otter impacts can be seen through the phenomenon of trophic cascades. Within the kelp forests, otters are the dominant predator, consuming many species of invertebrates such as sea urchins and abalone (Schiel and Foster, 2015). As the only marine mammal without blubber sea otters have …show more content…
A study of the Aleutian archipelago in the Northern Pacific Ocean looked at the changes in fish, specifically the rock greenling (Hexagrammos lagocephalus). The study was conducted during a period of rapid otter decline, however; not all the islands within the archipelago experienced a strong decline. This offered a period to study the changes in community structure with both the presence and absence of sea otters. Islands with few otters saw declines in rock greenling abundance, while islands with consistent otter presence did not. This was related to the presence or absence of kelp as the rock greenling relies on kelp for food, protection, and reproduction (Reisewitz et al., 2006). As otter populations declined, urchin populations increased, which in turn decreased kelp forest area available for rock greenlings to utilize. This study offered full view of the effects of natural sea otter declines in real time and the direct and indirect effects they can have on species outside of the traditional otter-urchin-kelp …show more content…
Studies have shown both support and refutation for sea otters being the main reason for trophic cascades within kelp forests. However; there are many changes that could be made to improve previous studies, which would help confirm the true role that sea otters play. Many studies need to be duplicated to confirm the results that were seen. The focus of the studies needs to be shifted from sea otters to kelp and urchin populations. This will lead to a smaller sampling error due to the fact that otters are roving predators so determining abundance is harder than measuring sedentary organisms like kelp and urchins (Estes et al., 2010). Looking into complex and multistep food web interactions, such as the study on the rock greenling, will provide further insight into the possible far reaching effects of sea otter predation. Finally, research on the different equilibrium states needs to be addressed further in other locations to confirm the viability of the urchin
Deborah Butterfield's "Otter" (2014) horse sculpture expresses a realistic display of beauty and craftsmanship because of its life-size image, the symbol of strength and the spirit it exerts where it is displayed at the Art Hotel in Denver, Colorado. "Otter" is a massive horse, standing at the entrance of the hotel, gazing toward the patio, looking as if it is going to trot right out the patio door. Deborah, born in San Deigo, California now lives in Montana and Hawaii. Montana and Hawaii have provided Deborah with the resources to create numerous horse sculptures, beginning with natural twigs and stems from the area. These tree stem creations are then constructed into free-standing, life-size bronze sculptures. The artist says, "I first used the horse images as a metaphorical substitute for myself-it was a way of doing a self-portrait one step removed from the specificity of Deborah Butterfield".
Isle Royal is an island surrounded by the cool Lake Superior. Wolf and Moose are the two largest species on the island, and the wolf and moose interaction is the longest running large mammal predator-prey study on earth (USNPS, 2014). The two populations were once said to exhibit some kind of “balance of nature,” now that is not believed to be the case (Vucetich, 2012).
We don’t often stop to consider the impact that simply living our human lives has on the other species that once called our neighbourhoods their home. The Fraser Valley, “one of the most important and complex ecosystems in the country” (Thom, p. 171), has been dramatically altered to make a more convenient landscape for housing and farming. In this process, critical habitat has been destroyed and many species that were once abundant have disappeared from our area (Cuthbert p. 24). Urbanization is ongoing and is thought to be the most significant threat to the incredible biodiversity found throughout British Columbia, and particularly the population-dense Lower Mainland (Harding, p. 355). Biodiversity, the “complex web that sustains life on this planet” (Austin, et al., p. 5), is vital for our survival as humans (Cuthbert p. 74). Any loss of biodiversity affects the entire ecosystem and all organisms within it (Fetene et al., p. 52). In the quest to house the ever-expanding human population, we must also consider habitat conservation and seek to preserve the rich biodiversity found in the Fraser Valley that supports and enriches our lives.
P6: ‘The animals behaviour and natural instinct changes in a marine park compared to in its natural habitat’ (para 3).
Lionfish are not currently listed as threatened in their native range. However, the increase in pollution in coral reefs can negatively affect the lionfish's primary food sources (NOAA, 2011). If lionfish are unable to adapt to declines in their prey species, their numbers will decrease. Although between the increasing reef pollution and the Lionfish’s voracious appetite reef populations will more than likely be damaged beyond repair, they may even be close to elimination by the time the Lionfish population actually declines (Albins, 2013).
Introduction Sea otters (Enhydra lutris) are marine mammals capable of spending their entire lives in water. Being carnivorous in nature, they feed on sea urchins, crabs, fishes, mussels and clams. They are referred to as keystone species due to their profound impact on marine ecology. The interaction between sea otters, sea urchins and kelp forests has been studied as a model for the impact of predator-prey interactions on community ecology. Sea otters are keystone predators, whose presence has a far-reaching influence on the marine food web by affecting the populations of sea urchins, which indirectly affects the populations of kelp forests & other marine organisms.
The processes of predation affect virtually every species to some degree or another. Predation can be defined as when members of one species eat (and/or kill) those of another species. The specific type of predation between wolves and large ungulates involves carnivores preying on herbivores. Predation can have many possible effects on the interrelations of populations. To draw any correlations between the effects of these predator-prey interactions requires studies of a long duration, and statistical analysis of large data sets representative of the populations as a whole.
Markovsky, Alexander. "Massive Cutbacks in Karelia's Nature." Taiga Rescue Network 2011-11-08. N.p., 8 Nov. 2011. Web. 17 Nov. 2013.
Save the World: Save the sea otters During the 18th and 19th centuries, sea otters were hunted for their luxurious pelts, and by the early 1900s, the species was believed to be extinct in California. (Carswell) Why do we care you ask, well not only are they super cute and eat with their hands. Apparently, a healthy population of sea otters keeps the sea urchin population in check. An unhealthy or small population of sea otters allows the sea urchin’s number to explode thus decimating kelp beds, which is the sea urchin’s food source, and causing a “chain reaction that depletes the food supply for other marine animals consequently causing their decline.
Marine Otters live out near the coast. They spend most of their time laying on their backs in the water eating fish and other shellfish. They have thick fur coats that keep them warm in the cold pacific waters.
The southern sea otter population is not increasing as quickly as scientist predicted because there are many variables which are affecting their rate of birth. If an oil spill happens to occur it would endanger the sea otters and threaten the kelp forest. According to the website "defenders.org", it states "When sea otters come into contact with oil, it causes their fur to mat, which prevents it from insulating their body" (www.defenders.org/sea-otter/threats). The sea otters would die and not be able to grow more in population. Often, every 3 years or so the population would increase but not by much. The "Monterey Bay Aquarium" data sheet states "In 2007 there were 2,818 total sea otters, in 2010 it decreased by 107 sea otters, in 2013
For example the canopies of kelp provide shelter for many organisms . Because the kelp is able to float, it creates a canopy. This canopy has warm temperatures and slow water currents, providing a home to defenseless young. This is important because the kelp is able to protect many organisms from predators and rough storms (6). Kelp is also the base of the food chain. Since kelp is the base of the food chain many organisms eat kelp and other animals eat them.This is important because without the kelp all the primary consumers would starve having no other food source (5). Finally each part of kelp is home to a different species. Because each part of kelp is home to a different species, many species breed in them. This is important because if the kelp where gone there would be no place for the organisms to breed downsizing their population (4). Overall kelp is providing food and shelter to many
Mills, Scott L., Daniel F. Doak, and Michael E. Soule. "The Keystone-species Concept in Ecology and Conservation." BioScience 43.4 (1993): 219-25. Apr. 1993. Web. 30 Oct. 2011.
With a coastline of over 202 000 km and over a fourth of the world’s freshwater resources, it is no wonder why Canada’s fishing industry is a huge part of its economy.1 Canada exports more than 75% of its fish to over 130 countries worldwide. Many of the 7 million people who reside on the coast depend on the ocean’s resources. In total, Canada’s entire fishing industry is worth around 5$ billion dollars a year, being one of the world’s most valuable. However, the coasts have not been treated by respect; overfishing, over consumption, and wasteful practices has deteriorated, not only the industry, but the ecosystems and fish populations. This is a huge global issue; the worldwide collapse of fisheries has been project for 2048. Slowly, as the trends continue, we will inevitably see many fish species start to disappear. In fact, the ill-treatment of species on the Canadian border has already devastated a large specie, the cod.
Lotze, Heike K., Marta Coll, Anna M. Magera, Christine Ward-Paige, and Laura Airoldi. "Recovery of Marine Animal Populations and Ecosystems." Trends in Ecology & Evolution 26.11 (2011): 595-605. Print.