FOSS Ecoscenarios: Monterey Bay National Marine Sanctuary Page 1 of 9 INTRODUCTION

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1 FOSS Ecoscenarios: Monterey Bay National Marine Sanctuary Page 1 of 9 INTRODUCTION Biome: Kelp Forest The Monterey Bay National Marine Sanctuary (NMS) stretches along the coast of California, from San Francisco to Santa Barbara. The sanctuary protects an area of unique biome known as the kelp forest. Here, kelp grows great heights from the rocky seabed to the ocean surface. This marine forest is home to rich marine biodiversity, including fish, sea otters, and many marine invertebrates. istockphoto/mpiotti Monterey Bay is one of 13 national marine sanctuaries. In the 1800s Americans recognized the need to protect certain areas of the United States from development, and to preserve them in their natural state. This led to the establishment of Yellowstone National Park in 1872, the US Forest Service in 1905, and the National Park Service in However, the oceans and coastal waters were not included in either of these systems. It was not until 1969, when a huge oil spill devastated the coastline of southern California, that the need to protect North America's coastal waters came to public attention. The National Marine Sanctuary System was established in 1972 as a division of the National Oceanic and Atmospheric Administration (NOAA). A national marine sanctuary is like a national FOSS Populations and Ecosystems Course, Second Edition Version date 12/2015

2 Page 2 of 9 park in the ocean. The sanctuaries protect marine habitats and local cultural history. Activities like dumping waste and drilling for oil are not allowed. Activities like fishing and recreation are permitted but regulated. Monterey Bay NMS was established in It is the largest national marine sanctuary, covering 13,730 square kilometers (km 2 ). In the 1800s, kelp farmers wrapped cables around large areas of kelp to pull it up for use. However, this practice prevented the kelp and its surrounding community from growing back quickly. Today, kelp is harvested by cutting the stipes (stems) about 1.2 meters (m) below the water s surface. This way the holdfast (root-like structure) and most of the stipe remain intact. The kelp regrows quickly and can be cut again later. Monterey Bay NMS offers many ecosystem services. Kelp is a source of algin, an ingredient in foods and other household products. In the sanctuary, kelp is harvested by hand to make food for farm-raised abalone. Kelp forests offer unique habitat for many organisms, including endangered species like sea otters. This diverse community attracts over 7 million visitors to Monterey County every year. Humans are adding extra carbon to the atmosphere in the form of carbon dioxide (CO 2) by burning fuels like wood, coal, oil, and gas. Increased CO 2 in the atmosphere is one cause of climate change. Changes to the climate patterns known as El Niño and La Niña patterns directly impact the stability of kelp forests. Through the process of photosynthesis, kelp converts CO 2 that could otherwise become greenhouse gases in the atmosphere into oxygen (O 2). Kelp stores the carbon in its biomass. This process is called carbon sequestration. A watershed is an ecosystem that contains a set of streams and rivers that all drain into a single larger body of water. The body of water could be a wetland, lake, pond, and groundwater (water stored underground). The watershed can also include cities, factories, mines, and farmland. Eleven major watersheds drain into Monterey Bay, flowing through major cities and vast farmlands. These human developments can affect the health of the watershed ecosystem and ultimately the kelp forests in Monterey Bay.

3 Page 3 of 9 Courtesy of National Oceanic and Atmospheric Administration This map shows the Monterey Bay NMS and the eleven watersheds that drain into the bay. In the past 40 years, the kelp population has declined dramatically in the sanctuary. Some of the main factors affecting the kelp population are kelp harvesting, mariculture (ocean farming), decline in sea otters populations, and pollution runoff from agriculture (land farming). Ecosystem Services Biological regulation: Sea otters are considered the keystone species of the kelp forest. Sea otters keep urchin populations in check, which in turn protects kelp populations. Climate regulation: Kelp forests help regulate the global climate by converting atmospheric CO 2 into O 2 and storing the carbon in the kelp biomass. Food: Algin in kelp is an important additive ingredient in many food products. Habitat refuge: Kelp forests are a unique habitat for many organisms. Natural resource: Algin in kelp is an additive used in toothpastes, shampoos, soap, pills, dyes, and paints. Nutrient cycling: Primary production in kelp forests is important for maintaining the carbon cycle. Primary Production: Many ecosystem services are possible because of the high primary productivity of kelp and phytoplankton.

4 Page 4 of 9 Tourism: Over 7 million tourists visit Monterey County every year. Because of this massive draw, there are over 22,000 full-time tourist-related jobs, generating over $2 billion of income for the county each year! ABIOTIC DATA The temperate climate in the Monterey Bay is relatively mild with warm summers and cool winters. A typical day during summer and early fall at Monterey Bay NMS is cool, with air temperatures of 16 degrees Celsius ( C) to 18 C. Winds blow from the northwest at about 15 km per hour. The skies may be somewhat cloudy, but rain rarely falls. This is the dry season at Monterey Bay. The wet season is between November and early April. Different amounts of rain fall at different places in Monterey Bay. During the wet season, temperatures are cooler but not extremely cold, usually about 10 C 13 C. A mix of subarctic and tropical waters affects the water temperature and salinity at Monterey Bay. Usually the salinity of the water (3.3 percent) is slightly less than the average ocean water salinity

5 Page 5 of 9 (3.5 percent). Streams flowing into the ocean can also affect salinity. The water is warmest in the early fall, 15 C, and coolest in the late winter, 11 C. Courtesy of NOAA Photo Library Light levels are low on the ocean bottom in a kelp forest. Light does not penetrate water easily. For this reason, the amount of light on the ocean's surface is not the same amount that hits the ocean floor. The top few meters has a lot of light and is called the photic zone. The amount of light decreases with depth. In some areas, light can penetrate as deep as 90 meters (m). In a kelp forest, the light cannot go as deep because the kelp is so dense. The area that does not have light is called the aphotic zone. In addition to kelp forests, Monterey Bay NMS also includes sandy beaches, coastal dunes, rocky intertidal areas, and deep ocean. These other habitats can have significant impacts on the kelp forest ecosystem. For example, in the spring, water from deep canyons moves up to the surface. This movement of water to the ocean surface is called upwelling. Upwelling brings cold, nutrient-rich water up into the photic zone, resulting in high productivity by phytoplankton. Upwelling is strongest in the spring. Every 3 to 7 years, a climate pattern called El Niño disrupts the ocean-atmosphere system in the Pacific Ocean. El Niño, which usually occurs in the winter, is caused by a change of current patterns near the equator. Weaker equatorial winds do not draw up the colder, nutrient-rich water from deep in the ocean. This allows the warmer, nutrient-poor surface water to flow in the currents that feed Monterey Bay. Without strong upwelling, water is warmer and the kelp forest is less productive.

6 FOSS Ecoscenarios: Monterey Bay National Marine Sanctuary Page 6 of 9 Courtesy of NOAA Photo Library In January 1998, during the El Niño event, warm equatorial waters did not contain nutrients needed by phytoplankton to grow and produce chlorophyll. Courtesy of NOAA Photo Library By July 1998, at the end of the El Niño event, colder equatorial water appeared. A bloom of photosynthetic phytoplankton and chlorophyll indicated increased nutrients. During an El Niño year, the water at Monterey Bay NMS and along the entire west coast of the United States is unusually warm, which results in higher rainfall and more storms. The year following an El Niño is usually a La Niña year. During La Niña, the water is cooler than normal and more productive. El Niño and La Niña patterns directly impact the stability of kelp forests. The ocean floor in Monterey Bay NMS is mostly hard granite. Within the sanctuary, the ocean floor drops gradually at first. This shallow area is the continental shelf. As you move farther from land, the ocean floor drops steeply onto the abyssal plain. The sanctuary also has underwater canyons up to 4,000 m deep. Monterey Canyon is the deepest, and it runs right out from Monterey Bay. Because these deep canyons are so close to shore, deep-ocean creatures can be observed near the coast, making Monterey Bay a unique area for research. Pollution refers to substances introduced by industry and other human activity that can harm an ecosystem. There are two main types of pollution: point source pollution and nonpoint source pollution. Point source pollution comes from an identifiable source like a pipe or factory smokestack. Federal laws like the Clean Water Act have regulated many forms of point source pollution. Nonpoint source pollution comes from many different sources that aren t always identifiable. Storm water runoff and accumulation of runoff from farms or lawns are examples of FOSS Populations and Ecosystems Course, Second Edition Version date 12/2015

7 Page 7 of 9 nonpoint source pollution. This form of pollution is much harder to control because there are so many contributing sources. Monterey Bay NMS is most affected by nonpoint source pollution. One kind of nonpoint source pollution is fertilizer. Land use of fertilizer can change the water. Fertilizers are chemicals with nutrients that help plants grow. This may sound helpful, but when too much fertilizer is sprayed on fields or lawns in nearby California, it runs off into streams and rivers that eventually carry it to the ocean. These chemicals stimulate unusual growth of algae and cyanobacteria, creating an excess of growth called algal blooms. These blooms can block sunlight from the kelp forests and stop the kelp from growing. They also produce toxins (harmful substances) that can threaten the health of humans and the kelp forest ecosystem. Sediments (sand and silt) in runoff can also block sunlight in the ocean and reduce kelp growth. All these sources of pollution are difficult to prevent because they come from many different places. Humans over a large area are affecting the water quality of Monterey Bay. BIOTIC DATA In a kelp forest, the trees of this forest are actually species of brown algae commonly known as kelp. Kelp forests are one of the most productive ecosystems on Earth. In addition to kelp, phytoplankton, algae and zooxanthellae enrich the ecosystem. Annual primary productivity is the amount of energy provided by the producers to the ecosystem each year. In Monterey Bay, the annual primary productivity is dependent on the amount of upwelling that year. During years of significant upwelling, the productivity of kelp forests is as high as tropical rain forests and coral reefs. During upwelling events, kelp forest primary productivity is as high as tropical rain forests and coral reefs. Like terrestrial forests, kelp forests have patterns of seasonal growth. In the spring, juvenile kelp grow quickly. By summer, there is a lush canopy of kelp. In the fall, growth slows and the kelp fronds become ragged and torn. In the winter, when the surf is rougher, older kelp can tear loose from the ocean floor. Giant kelp grows very slowly in the winter.

8 Page 8 of 9 Kelp requires cold temperatures to reproduce sexually, which starts the cycle over each year. During El Niño years, when the temperatures are higher than normal, the kelp may not be able to reproduce. For giant kelp, this results in older and more fragile kelp throughout the kelp forest the next year. Courtesy of Monterey Bay NMS Kelp continues to grow up to 0.6 m per day after reaching the water surface. The fronds form a dense mat along the surface. The kelp forest can be divided into layers that support different communities of organisms: substrate, mid-water, and canopy. The substrate layer is at the bottom, where the kelps are attached to rocks with root-like structures called holdfasts. Abalones, bat stars, brittle stars, and sea urchins are a few of the animals found in the substrate layer. Spiny lobsters and hermit crabs hide in the rocks and scavenge for bits of detritus. The mid-water layer is where the leaf-like fronds of kelp are suspended in the water. Turban snails cruise up and down the fronds in search of food. Fish such as garibaldi, sheepheads, and giant kelpfish swim among the fronds. Kelp crabs climb up and down the kelp stipe, adding bits of kelp to their carapace for camouflage. The canopy layer is closest to the surface. Here, the kelp blades bob on the surface waves. Colorful nudibranchs slide across the kelp blades. Some kelp fronds are covered with small encrusting bryozoans. Zooplankton and phytoplankton float in the water near the surface, moving with the current. Courtesy of National Oceanic and Atmospheric Administration The kelp forest supports different communities at different depths in the water.

9 Page 9 of 9 Throughout the many layers, predators such as leopard sharks, red octopus, and sea otters hunt for food. One important ecological role is known as a keystone species. The term keystone comes from the name of a stone used when constructing stone arches. This important stone holds the other stones in place. Similarly, keystone species play an important role in maintaining a community of organisms. Not all communities have keystone species, but for those that do, the loss of that one species can destroy the whole ecosystem. Sea otters are considered the keystone species of the kelp forest, and they have been hunted nearly to extinction. Recent efforts to restore sea otter populations have had significant positive impacts on the health of the ecosystem as a whole. Southern sea otters have a broad diet of shellfish, sea urchins, crab, fish, and snails. Otters use rocks, shells, and even discarded glass soda bottles as tools to help break open urchins and shellfish. They have voracious appetites and may eat up to one-quarter of their weight each day. Sea otters can limit the population of sea urchins, which is good for the kelp forest because sea urchins eat so much kelp that they can create large areas where the kelp is entirely gone. These areas are called urchin barrens. Researchers learned that the presence of sea otters is essential to keeping urchin populations stable. After steady growth, sea otter populations have been declining in recent years. Scientists are working hard to find answers. Some factors that may be causing the sea otter decline include boating activities by humans, fishing in the area, and pollution. About 40 percent of sea otters die from disease, which could be caused by increased pollution. As a result of their protection under the Endangered Species Act, the number of otter deaths directly related to human conflict are decreasing, and regulation for harmful fishing nets have improved. Courtesy of Monterey Bay NMS Sea otters float atop the kelp forest at Cannery Row.