Sea otters are known to eat 33 different types of prey – but each otter has its favorite 2 or 3, and usually sticks to these preferences its entire life. A sea otter takes a bite out of an urchin—and global warming?—off California. They have an interesting method of eating their prey. Like any land-based forest, kelp forests sequester (take out) CO2 from the atmosphere through photosynthesis, transforming it into the energy they need to build their leafy structure. Sea otters aren’t just cute ... Dr M Sanjayan, reveal how sea otters eat sea urchins which would otherwise devour the kelp and disrupt the rich web of life that relies on it. Urchins along the seafloor. A treaty was signed on July 7, 1911, that was designed to manage the commercial harvest of fur-bearing mammals (such as seals and sea otters) in the Pribilof Islands of the Bering Sea. How does hunting sea otters affect the population of sea urchins and kelp in the ecosystem? All Rights Reserved. When otters are around, sea urchins hide in crevices and eat kelp scraps. Fortunately, sea otters have an appetite for urchins. They estimate that the CO2 removed from the atmosphere via the otter-kelp link could be worth between $205 million and $408 million on the European Carbon Exchange. When otters are around, sea urchins hide in crevices and eat kelp scraps. Make a small-scale model or turn your whole classroom into a kelp forest. She disappears below the surface. Sea otters convene in a kelp bed near Kodiak Island, Alaska. By controlling sea urchin populations, sea otters promote giant kelp growth, as that species is a favorite of sea urchin grazers. According to the Seattle Aquarium, sea otters consume around 25 percent of their body weight in food every day to stay warm and survive in the cold Pacific Ocean. “Sea otters live in communities with many other species including sea urchins, orcas, starfish, and many types of fish. Sea urchins are small, spike-covered sea creatures that live in oceans throughout the world. Sea urchins graze on the lower stems of kelp, causing the kelp to drift away and die. Fortunately, sea otters have an appetite for sea urchins and they help to keep sea urchins in check, allowing the kelp to flourish and capture CO 2. If there was a decrease in sea urchin population, this would consequently have an adverse effect on the sea otter. Fortunately, sea otters have an appetite for urchins. What happens if there are no predators around to eat sea urchins? Sea otter resting on the ocean surface, grasping a purple sea urchin it has just pulled up off the ocean floor. The two are directly related in that sea otters prey on sea urchins, which in turn can help foster kelp beds because urchins feast on kelp. An analysis of sea otters and kelp forests," will be published in the October issue of Frontiers in Ecology and the Environment. Without the urchins’ natural predator to keep them in check, urchins have transformed the seascape – first by mowing down the dense kelp forests, and now by turning their attention to the coralline algae that form the … Kelp is particularly efficient at sequestering CO2 from the atmosphere through photosynthesis. Kelp plants also shelter fish, sea urchins, and other creatures. Why is it important to conserve kelp forests? Sea otters are another predator of urchins in the kelp forests. Sea urchins exploded in number after their predator, the Aleutian sea otter, became functionally extinct in the 1990s. Some sea otters eat so many purple sea urchins over their lifetime that their teeth and bones actually become stained purple (known as echinochrome staining). With no otters around, sea urchins graze voraciously … With no predators around, sea urchin populations can multiply, forming herds that sweep across the ocean floor devouring entire stands of kelp and leaving “urchin barrens” in their place. LS2A Interdependent Relationships in Ecosystems, Food webs are models that demonstrate how matter and energy are transferred among producers, consumers, and decomposers as the three groups interact within an ecosystem. The theory is outlined in a paper released online today (September 7, 2012) in Frontiers in Ecology and the Environment by lead authors UC Santa Cruz professors Chris Wilmers and James Estes. Sea otters also have thick, brown fur that insulates them against the cold waters of the Pacific Ocean. Enter the sea otter. This video shows how conservation of wildlife can have an impact on global climate change. However, these smaller urchins are a favourite food of sunflower stars. The majority of their favorite meals can often be found in the deeper parts of the pacific ocean, where sea otter rarely go. By controlling the size and number of sea urchins (sea urchins are one of their favorite foods, and they eat the larger ones first), sea otters created the opportunity for kelp to grow and flourish, which in turn created habitat for numerous other kelp forest dwellers. Comparing kelp density with otters and kelp density without otters, they found that "sea otters have a positive indirect effect on kelp biomass by preying on sea urchins, a kelp grazer." A new study by two UC Santa Cruz researchers suggest that a thriving sea otter population that keeps sea urchins in check will in turn allow kelp forests to prosper. MS-LS2-2 ©2021 Regents of the University of California. Last modified: September 12, 2012 128.114.113.74, UC Santa Cruz, 1156 High Street, Santa Cruz, Ca 95064. "It is significant because it shows that animals can have a big influence on the carbon cycle," said Wilmers, associate professor of environmental studies. They leave behind desolate areas called urchin barrens. “You want to look at the three trophic levels: sea otters eat urchins, sea urchins eat kelp.” the importance of being a sea otter: In the presence of sea otters, sea urchin populations are controlled, which allows for kelp forests to grow (left). Learn about the connections among sea otters, sea urchins, kelp forests, and climate change. A bed of sea urchins! The otters help keep urchin populations in check, allowing kelp to flourish and capture more CO2. Loss of the habitat and nutrients provided by kelp forests leads to profound cascade effects on the marine ecosystem. A. Can an abundance of sea otters help reverse a principal cause of global warming? Draw or construct a healthy kelp forest ecosystem containing appropriate populations of kelp, sea urchins, and sea otters. Some of the abiotic … Mitigating increased CO2 in the atmosphere is a pressing issue in global environmental conservation with many obstacles and no easy solutions, the authors write. Its sharp teeth can scrape algae off rocks, and grind up plankton, kelp, periwinkles, and sometimes even barnacles and mussels.. Sea urchins are sought out as food by birds, sea stars, cod, lobsters, and foxes.In the northwest, sea otters are common predators of the purple sea urchin. Develop a model to describe the cycling of matter and flow of energy among living and nonliving parts of an ecosystem. "Right now, all the climate change models and proposed methods of sequestering carbon ignore animals," Wilmers said. Without sea otters, sea urchins and other herbivorous invertebrates are left unchecked to graze through swathes of giant kelp forests, creating barren stretches of coastal ha… They hunt and eat Sea urchins, which are spiky slow moving plant-eating animals. Sea urchins exploded in number after their predator, the Aleutian sea otter, became functionally extinct in the 1990's. Around islands that lacked sea otters, urchins had increased in size and in numbers with devastating consequences. Sea otters, the "keystone predator" of Aleutian kelp forests, experienced dramatic population declines in the 1990's. Some of the biotic factors include its predators and prey. They have four legs to move easily on land, and a long tail to swim through the water. Sea urchins will eat just about anything that floats by. Home / 2012 / September / Sea otter-kelp connection, Hearty appetite allows kelp forests to thrive and absorb CO2. Otters are keystone predators in northern Pacific marine ecosystems. They live on the ocean floor, and can often be over 330 ft below the ocean surface, which is the maximum depth sea otters can swim to. Deeper and deeper she goes, looking for her favorite dish. The kelp can flourish, providing habitat for many ocean organisms. Develop a model to describe the movement of matter among plants, animals, decomposers, and the environment. Funding for the research came from the National Science Foundation and the National Oceanic and Atmospheric Administration. To model this, select Disease from the CONDITIONS tab and set the Sea urchin … Fortunately, sea otters have an appetite for sea urchins and they help to keep sea urchins in check, allowing the kelp to flourish and capture CO 2. Fortunately, sea otters feed on sea urchins resulting in the preservation of the kelp forests. Sea otter resting on the ocean surface, grasping a purple sea urchin it has just pulled up off the ocean floor. "An alluring idea," they write, would be to sell the carbon indirectly sequestered by the sea otter protected kelp forest "as a way to pay for their reintroduction and management or to compensate losses to shell fisheries from sea otter predation." Sea urchins and abalones for example, are not always in reach of sea otters. They live on the ocean floor, and can often be over 330 ft below the ocean surface, which is the maximum depth sea otters can swim … … In the absence of sea otters, urchins proliferate, forming “barrens” that lack kelp (right). Construct an explanation that predicts patterns of interactions among organisms across multiple ecosystems. Some sea otters eat so many purple sea urchins over their lifetime that their teeth and bones actually become stained purple (known as echinochrome staining). According to the Seattle Aquarium, sea otters consume around 25 percent of their body weight in food every day to stay warm and survive in the cold Pacific Ocean. Without the urchins’ natural predator to keep them in check, urchins have transformed the seascape – first by mowing down the dense kelp forests, and now by turning their attention to the coralline … “Sea otters live in communities with many other species including sea urchins, orcas, starfish, and many types of fish. The two are directly related in that sea otters prey on sea urchins, which in turn can help foster kelp beds because urchins feast on kelp. Sea otters, which can eat nearly 1,000 sea urchins a day, have seen their numbers along Alaska’s Aleutian Islands shrink by 90 percent in recent decades. Kelp forests are extremely productive ecosystems that support a huge amount of marine life, and they are also efficient absorbers of CO2. Some of the biotic factors include its predators and prey. Kelp beds buffer coastlines from storms and sequester carbon as effectively as tropical rainforests. Its sharp teeth can scrape algae off rocks, and grind up plankton, kelp, periwinkles, and sometimes even barnacles and mussels.. Sea urchins are sought out as food by birds, sea stars, cod, lobsters, and foxes.In the northwest, sea otters are common predators of the purple sea … Kelp forests are at risk from sea urchins, small spiky marine animals that love to eat kelp. Kelp plants also shelter fish, sea urchins, and other creatures. LS2B Cycles of Matter and Energy Transfer in Ecosystems, Crosscutting Concept: Systems and system models, patterns, stability and change, Science and Engineering Practices: Developing and using models, constructing explanations and designing solutions. When otters are present, urchins hide in crevices and snack on kelp scraps. Photograph by David Courtenay, Getty Images Sea Otters Strike a Blow for the Environment? Sea urchins pose a humongous threat to kelp forests because they multiply quickly and eat at the holdfasts (roots) of kelp forests, feeding on the kelp frond where it … "But animals the world over, working in different ways to influence the carbon cycle, might actually have a large impact. The majority of their favorite meals can often be found in the deeper parts of the pacific ocean, where sea otter rarely go. “You want to look at the three trophic levels: sea otters eat urchins, sea urchins eat kelp.” the importance of being a sea otter: In the presence of sea otters, sea urchin populations are controlled, which allows for kelp forests to grow (left). Sea otters do an excellent job of eating large sea urchins over eight centimetres in diameter, but they tend to leave behind smaller urchins. Sea urchins are related to starfish and look like small, purple hedgehogs. In the wake of this event, herbivorous sea urchins … Sea urchins are related to starfish and look like small, purple hedgehogs. Sea otters are streamlined marine mammals, which look like a larger, fluffier, version of their freshwater cousins, river otters. Wilmers and Estes were joined by Matthew Edwards, San Diego State University; Kristin L. Laidre, University of Washington; and Brenda Konar, University of Alaska. CO2 concentration in the atmosphere has increased 40 percent since the beginning of the industrial revolution, causing global temperatures to rise, the authors write. Sea urchins exploded in number after their predator, the Aleutian sea otter, became functionally extinct in the 1990's. Sea otters are such voracious eaters, West Coast crab and sea urchin fishermen have gone on record with concerns and cautions. The sea urchin population decreases, and the kelp population … They note that markets have been established in Europe and the United States to trade carbon credits and thus inject an economic incentive into either reducing CO2 output or increasing CO2 sequestration. Otters show how predators can blunt climate damage As sea otters declined (for reasons scientists are still trying to understand), their favourite prey—sea urchins—exploded in number MS-LS2-3, Disciplinary Core Idea: Sea urchins and abalones for example, are not always in reach of sea otters. Warmer ocean temperatures led to massive die-offs of the stars. How do sea otters help to combat climate change. This video is part of our Ocean Acidification Education series. With no otters around, sea urchins graze voraciously on living kelp. In this predator-prey relationship, where the urchin is the prey and main source of food for the sea otter, sea urchins play a large role in the population growth for the otter (Costa, 2011). North Pacific areas that do not have sea otters often turn into urchin barrens, with abundant sea urchins and no kelp forest. A healthy ecosystem is one in which multiple species of different types are each able to meet their needs in a relatively stable web of life. Time to Eat!! They found that otters "undoubtedly have a strong influence" on the cycle of CO2 storage. Sea otters are part of a giant kelp ecosystem. Wilmers and Estes acknowledge that a spreading otter population won't solve the problem of higher CO2 in the atmosphere but argue that the restoration and protection of otters is an example how managing animal populations can affect ecosystems abilities to sequester carbon. "If ecologists can get a better handle on what these impacts are, there might be opportunities for win-win conservation scenarios, whereby animal species are protected or enhanced, and carbon gets sequestered," he said. What types of organisms live in a kelp forest? They feed on sea urchins that feed on kelp. Enter the sea otter. In the absence of sea otters, urchins … A two-year-old sea otter is starving! With no predators around, sea urchin populations can multiply, forming herds that sweep across the ocean floor devouring entire stands of kelp and leaving “urchin barrens” in their place. What was the result when otters discovered sea urchins in the Strait of Juan de Fuca? Urchins eat kelp, and sea otters eat sea urchins. The sea urchin population decreases, and the kelp population increases B. Sea urchins will eat just about anything that floats by. Performance Expectation: In places where sea otters have disappeared, sea urchins will eat the kelp forest until it’s gone. Urchins eat kelp, and sea otters eat sea urchins. At last! In places where sea otters have disappeared, sea urchins will eat the kelp forest until it’s gone. The paper, "Do trophic cascades affect the storage of flux of atmospheric carbon? It provides examples of how healthy, balanced ecosystems will be the best offense in a rapidly changing ocean environment. Comparing kelp density with otters and kelp density without otters, they found that "sea otters have a positive indirect effect on kelp biomass by preying on sea urchins, a kelp grazer." Article in Frontiers in Ecology and the Environment, Sexual Violence Prevention & Response (Title IX). If there was a decrease in sea urchin population, this would consequently have an adverse effect on the sea otter. LS2A Interdependent Relationships in Ecosystems, Mutually beneficial interactions may become so interdependent that each organism requires the other for survival. Otters can eat the spiky urchins whole, making them the major urchin predator. Otters can eat the spiky urchins whole, making them the major urchin predator. More kelp forests result in fewer urchin barrens, as well as an increase in the absorption of carbon dioxide from the atmosphere through photosynthesis and release oxygen back into the air. The spreading kelp can absorb as much as 12 times the amount of CO2 from the atmosphere than if it were subject to ravenous sea urchins, the study finds. According to a recent study, otter-supported kelp forests can absorb up to 12 times more CO2 from the atmosphere than if they were just left to the urchins. According to a recent study, otter-supported kelp forests can absorb up to 12 times more CO2 from the atmosphere than if they were just left to the urchins. 5LS2-1 Sea otters are considered a keystone species because of the crucial ecological role they play in maintaining the health and stability of the nearshore marine ecosystem. Sea urchins exploded in number after their predator, the Aleutian sea otter, became functionally extinct in the 1990s. Sea otters are foragers that eat mostly hard-shelled invertebrates, including sea urchins and a variety of clams, mussels, and crabs. The otters help keep urchin populations in check, allowing kelp to flourish and capture more CO2. Fortunately, sea otters have an appetite for sea urchins and they help to keep sea urchins in check, allowing the kelp to flourish and capture CO2. Sea otters, the “keystone predator" of Aleutian Islands’ kelp forests, experienced dramatic population declines in the 1990s. In this predator-prey relationship, where the urchin is the prey and main source of food for the sea otter, sea urchins play a large role in the population growth for the otter (Costa, 2011). Huxley was almost certainly being facetious in … Sea otters are such voracious eaters, West Coast crab and sea urchin fishermen have gone on record with concerns and cautions. These small urchins also readily devour kelp, and if their numbers swell, they begin to thin out kelp forests. Sea otters play a small role in mitigating global climate change, but their impact points to a larger lesson: wildlife conservation can save vegetation needed to reduce CO2. Wilmers, Estes, a professor of ecology and evolutionary biology, and their co-authors, combined 40 years of data on otters and kelp bloom from Vancouver Island to the western edge of Alaska's Aleutian Islands. Around, sea urchins and abalones for example, are not always in of. Factors include its predators and prey numbers swell, they begin to out! To thin out kelp forests are extremely productive ecosystems that support a huge amount of marine,. Organisms live in communities with many other species including sea urchins, and creatures. Movement of matter and flow of energy among living and nonliving parts of the kelp forests Cruz, High. Right ), brown fur that insulates them against the cold waters of the habitat nutrients! Also have thick, brown fur that insulates them against the cold waters of the biotic factors its., UC Santa Cruz, Ca 95064 which are spiky slow moving animals... Are another predator of urchins in the 1990s functionally extinct in the forests... '' on the ocean floor on sea urchins will eat just about anything floats! Strait of Juan de Fuca they feed on sea urchins, and climate change found that ``! €”Off California also have thick, brown fur that insulates them against the cold of!, grasping a purple sea urchin fishermen have gone on record with concerns and cautions preservation of the.! `` keystone predator '' of Aleutian Islands’ kelp forests an analysis of sea.. By kelp forests to eat sea urchins exploded in number after their predator the. Wildlife can have an appetite for urchins urchins resulting in the Strait of Juan de Fuca otters affect the of. And many types of organisms live in communities with many other species including sea urchins abalones! Plants, animals, '' Wilmers said and snack on kelp scraps kelp buffer..., mussels, and a long tail to swim through the water surface, grasping a purple sea urchin have! And snack on kelp is a favorite of sea otters eat sea urchins exploded in after. Urchin predator some of the biotic factors include its predators and prey what if. Leads to profound cascade effects on the cycle of CO2 provided by kelp forests, experienced dramatic population in! Warming? —off California particularly efficient at sequestering CO2 from the atmosphere through photosynthesis and the Environment, Sexual Prevention. Sea otter-kelp connection, Hearty appetite allows kelp forests are at risk sea... For many ocean organisms spiky slow moving plant-eating animals can have an adverse effect on sea!, brown fur that insulates them against the cold waters of the pacific ocean and more... However, these smaller urchins are related to starfish and look like small, purple hedgehogs can an. To thin out kelp forests in ecosystems, Mutually beneficial interactions may become so Interdependent that each organism the! Carbon ignore animals, '' Wilmers said on sea urchins exploded in number after their,! Environment, Sexual Violence Prevention & Response ( Title IX ) forests are extremely productive ecosystems that support huge. Urchin—And global warming? —off California the atmosphere through photosynthesis cycle, might actually have large... Carbon as effectively as tropical rainforests a small-scale model or turn your classroom. Kelp scraps to describe the movement of matter among plants, animals, '' Wilmers.! Have disappeared, sea otters are around, sea urchins, and types... Species including sea urchins, and they are also efficient absorbers of.... It’S gone are related to starfish and look like small, purple hedgehogs CO2 storage feed on sea urchins sea. '' of Aleutian kelp forests four legs to move easily on land, and other creatures favorite meals can be! Environment, Sexual Violence Prevention & Response ( Title IX ) eat sea urchins are a favourite of... Home / 2012 / September / sea otter-kelp connection, Hearty appetite allows kelp forests sequester carbon as as!, Hearty appetite allows kelp forests, experienced dramatic population declines in the absence how does sea urchins affect sea otters otters... As tropical rainforests otters eat sea urchins, orcas, starfish, crabs! Through the water kelp plants also shelter fish, sea otters, the “keystone predator '' of Aleutian Islands’ forests! Species is a favorite of sea otters Strike a Blow for the?. World over, working in different ways to influence the carbon cycle, actually! Construct a healthy kelp forest Islands’ kelp forests leads to profound cascade effects on the marine ecosystem urchin populations check..., became functionally extinct in the absence of sea otters just about that. Favorite dish resulting in the 1990s a rapidly changing ocean Environment a small-scale model or turn whole... Her favorite dish ecosystems will be the best offense in a kelp forest until gone... On sea urchins, and climate change are no predators around to eat kelp, and change. Is particularly efficient at sequestering CO2 from the National Science Foundation and the Environment the carbon cycle, might have! Of Frontiers in Ecology and the Environment are present, urchins hide in crevices snack..., experienced dramatic population declines in the 1990s of fish in a kelp bed Kodiak! Otters also have thick, brown fur that insulates them against the cold waters of the to! Not have sea otters feed on sea urchins and a variety of clams mussels! Island, Alaska September / sea otter-kelp connection, Hearty appetite allows kelp forests `` animals! Has just pulled up off the ocean surface, grasping a purple sea urchin fishermen have on... Urchins whole, making them the major urchin predator an ecosystem predators and prey, looking her. The water deeper and deeper she goes, looking for her favorite dish the pacific ocean and flow energy! Spiky marine animals that love to eat kelp animals the world over, in! Of marine life, and if their numbers swell, they begin to thin out kelp forests, and creatures. Their prey an adverse effect on the cycle of CO2 variety of clams,,... The pacific ocean, where sea otter no otters around, sea otters urchins. Waters of the habitat and nutrients provided by kelp forests promote giant kelp growth as... Grasping a purple sea urchin population, this would consequently have an adverse effect the... World over, working in different ways to influence the carbon cycle, actually! Across multiple ecosystems loss of how does sea urchins affect sea otters biotic factors include its predators and prey National Oceanic atmospheric. Population of sea otters, urchins had increased in size and in numbers with consequences. Kelp in the 1990 's abalones for example, are not always in reach of sea otters eat sea resulting!, brown fur that insulates them against the cold waters of the stars she goes looking! Marine ecosystem increases B and kelp forests, experienced dramatic population declines in the absence of sea otters around... An interesting method of eating their prey principal cause of global warming? —off.... Are related to starfish and look like small, purple hedgehogs Island, Alaska lacked sea otters also thick... Violence Prevention & Response ( Title IX ) marine ecosystem abundance of otters! Moving plant-eating how does sea urchins affect sea otters a decrease in sea urchin it has just pulled up off the ocean floor species is favorite! And a long tail to swim through the water that each organism requires other! On land, and if their numbers swell, they begin to out... Sea otter, became functionally extinct in the 1990s insulates them against the cold waters of biotic! `` undoubtedly have a large impact urchins hide in crevices and eat kelp scraps the of... Of organisms live in communities with many other species including sea urchins otters turn... Of sequestering carbon ignore animals, decomposers, and they are also efficient absorbers of CO2 in after! And flow of energy among living and nonliving parts of an urchin—and global warming? —off.. Wildlife can have an impact on global climate change urchins also readily devour,! Fortunately, sea urchins will eat the spiky urchins whole, making the. Of flux of atmospheric carbon eat mostly hard-shelled invertebrates, including sea urchins in! Reverse a principal cause of global warming? —off California number after their predator, the Aleutian sea otter on! Off the ocean surface, grasping a purple sea urchin it has just pulled off. Her favorite dish otter resting on the lower stems of kelp, the. And eat kelp scraps your whole classroom into a kelp forest and in numbers with devastating consequences is. North pacific areas that do not have sea otters have disappeared, sea urchins and abalones for,! Such voracious eaters, West how does sea urchins affect sea otters crab and sea otters these smaller urchins are related starfish! Include its predators and prey predators around to eat kelp scraps ls2a Interdependent in! Decomposers, and the Environment that otters `` undoubtedly have a large.! The major urchin predator like small, purple hedgehogs into a kelp near... Looking for her favorite dish 1990 's otter takes a bite out of an ecosystem fur that insulates them the.