The ocean is one of Earth's most valuable natural resources. It provides food in the form of fish and shellfish—about 200 billion pounds are caught each year. It's used for transportation—both travel and shipping. It provides a treasured source of recreation for humans. It is mined for minerals (salt, sand, gravel, and some manganese, copper, nickel, iron and cobalt can be found in the deep sea) and drilled for crude oil.
The ocean plays a critical role in removing carbon from the atmosphere and providing oxygen. It regulates Earth's climate. The ocean is an increasingly important source of biomedical organisms with enormous potential for fighting disease. These are just a few examples of the importance of the ocean to life on land. Explore them in greater detail to understand why we must keep the ocean healthy for future generations....
Fishing Facts
The oceans have been fished for thousands of years and are an integral part of human society. Fish have been important to the world economy for all of these years, starting with the Viking trade of cod and then continuing with fisheries like those found in Lofoten, Europe, Italy, Portugal, Spain and India. Fisheries of today provide about 16% of the total world’s protein with higher percentages occurring in developing nations. Fisheries are still enormously important to the economy and well being of communities.
The word fisheries refers to all of the fishing activities in the ocean whether they are to obtain fish for the commercial fishing industry, for recreation, to obtain ornamental fish or fish oil. Fishing activities resulting in fish not used for consumption are called industrial fisheries. Fisheries are usually designated to certain ecoregions like the salmon fishery in Alaska, the Eastern Pacific tuna fishery or the Lofoten island cod fishery. Due to the relative abundance of fish on the continental shelf, fisheries are usually marine and not freshwater.
Although a world total of 86 million tons of fish were captured in 2000, China’s fisheries were the most productive, capturing a whopping one third of the total. Other countries producing the most fish were Peru, Japan, the United States, Chile, Indonesia, Russia, India, Thailand, Norway and Iceland- with Peru being the most and Iceland being the least. The number of fish caught varies with the years but appears to have leveled off at around 88 million tons per year possibly due to overfishing, economics and management practices.
Fish are caught in a variety of ways including one man casting nets, huge trawlers, seining, driftnetting, handlining, longlining, gillnetting and diving. Other than overfishing, fishing practices harmful to the environment are illegal and often used in developing countries where local fisherman have no other immediate choice.
The most common species making up the global fisheries are herring, cod, anchovy, flounder, tuna, shrimp, mullet, squid, crab, salmon, lobster, scallops and oyster. Mollusks and crustaceans are also widely sought. The fish that are caught are not always used for food. In fact, about 40% of fish are used for other purposes such as fishmeal to feed fish grown in captivity. For example cod is used for consumption but also to freeze for later use. Atlantic herring is used for canning, fishmeal and fish oil. The Atlantic menhaden is used for fishmeal and fish oil and Alaska Pollock is consumed but also used for fish paste to simulate crab. The Pacific cod has recently been used as a substitute for Atlantic cod which has been overfished.
The amount of fish available in the oceans is an ever-changing number due to the effects of both natural causes and human developments. It will be necessary to manage ocean fisheries in the coming years to make sure the number of fish caught never makes it to zero. A lack of fish greatly impacts the economy of communities dependent on the resource as can be seen in Japan, eastern Canada, New England, Indonesia and Alaska. The anchovy fisheries off the coast of western South America have already collapsed and with numbers dropping violently from 20 million tons to 4 million tons- they may never fully recover. Other collapses include the California sardine industry, the Alaskan king crab industry and the Canadian northern cod industry. In Massachusetts alone the cod, haddock and yellowtail flounder industries have collapsed causing an economic disaster for the area.
Due to the importance of fishing to the worldwide economy and the need for humans to understand human impacts on the environment, the academic division of fisheries science was developed. Fisheries science includes all aspects of marine biology in addition to economics and management skills and information. Marine conservation issues like overfishing, sustainable fisheries and management of fisheries are also examined through fisheries science.
In order for there to be plenty of fish in the years ahead, fisheries will have to develop sustainable fisheries and some will have to close. Due to the constant increase in the human population the oceans have been overfished with a resulting decline of fish crucial to the economy and communities of the world. The control of the world’s fisheries is a controversial subject, as they cannot produce enough to satisfy the demand, especially when there aren’t enough fish left to breed in healthy ecosystems. Scientists are often in the role of fisheries managers and must regulate the amount of fishing in the oceans, a position not popular with those who have to make a living fishing ever decreasing populations.
The two main questions facing fisheries management are:
1) What is the carrying capacity of the ocean? How many fish are there and how many of which type of fish should be caught to make fisheries sustainable?
2) How should fisheries resources be divided among people?
Fish populate the ocean in patches instead of being spread out throughout the enormous expanse. The photic zone is only 10-30 m or 30-100 ft deep near the coastline, a place where phytoplankton have enough solar energy to grow in abundance and fish have enough to eat. Most commercial fishing takes place in these coastal waters as well as estuaries and the slope of the continental shelf. High nutrient contents from upwelling, run-off, the regeneration of nutrients and other ecological processes supply fish in these areas with the necessary requirements for life. The blue color of the water near the coastlines is the result of chlorophyll contained in aquatic plant life.
Most fish are only found in very specific habitats. Shrimp are fished in river deltas that bring large amounts of freshwater into the ocean. The areas of highest productivity known as banks are actually where the continental shelf extends outward towards the ocean. These include the Georges Bank near Cape Cod, the Grand Banks near Newfoundland and Browns bank. Areas where the ocean is very shallow also contain many fish and include the middle and southern regions of the North Sea. Coastal upwelling areas can be found off of southwest Africa and off South America’s western coast. In the open ocean, tuna and other mobile species like yellowfin can be found in large amounts.
The question of how many fish there are in the ocean is a complicated one but can be simplified using populations of fish instead of individuals. The word “cohort” refers to the year the fish was born and is used to gather population statistics. Cohorts start off as eggs with an extremely high rate of mortality, which declines as the fish gets older. Juvenile fish close to the age where they can be fished are called recruits. Cohort mortality is tied in with the species of fish due to variances in natural mortality. The biomass of a particular cohort is greatest when fish are rapidly growing and decreases as the fish get older and start to die.
Scientists used theories and models to help determine the number and size of fish populations in the ocean. Production theory is the theory that production will be highest when the number of fish does not overwhelm the environment and there are not too few for genetic diversity of populations. The maximum sustainable yield is produced when the population is of intermediate size. Yield-per-recruit theory is the quest to determine the optimum age for harvesting fish. The theory of recruitment and stock allows scientists to make a guess about the optimum population size to encourage a larger population of recruits. All of the above theories must be flexible enough to allow natural fluctuations in the fish population to occur and still gather significant data. However, the theories are limited when taking into account the effect of humans on the environment and misinformation could result in overfishing or underfishing of the oceans resources.
Other factors that must be taken into account are the ecological requirements of individual fish species like predation and nutrition and why fish will often migrate to different areas. Water temperatures also influence the behavior of ecosystems causing an increase in metabolism and predation or a sort of hibernation. Even the amount of turbulence in the water can affect predator- prey relationships with more meetings between the two when waters are stirred up. Global warming could have a huge economic impact on the fisheries when fish stocks are forced to move to waters with more tolerable temperatures.
In many countries, commercial fishing has found more temporarily economical ways of catching fish including gill nets, purse seines, and drift nets. Although fish are trapped efficiently in one day using these fishing practices, the number of fish that are wasted this way has reached 27 million tons per year not to mention the crucial habitats destroyed that are essential for the regeneration of fish stocks. In addition, marine mammals and birds are also caught in these nets. The wasted fish and marine life is referred to as bycatch, an unfortunate side-effect of unsustainable fishing practices that can turn the ecosystem upside-down and leave huge amounts of dead matter in the water. Other human activities like trawling and dredging of the ocean floor have bulldozed over entire underwater habitats. The oyster habitat has been completely destroyed in many areas from the use of the oyster patent tong and sediment buildup draining from farm runoff.
Shipping
The word “shipping” refers to the activity of moving cargo with ships in between seaports. Wind-powered ships exist but more often ships are powered by steam turbine plants or diesel engines. Naval ships are usually responsible for transporting most of trade from one country to another and are called merchant navies. The various types of ships include container ships, tankers, crude oil ships, product ships, chemical ships, bulk carriers, cable layers, general cargo ships, offshore supply vessels, Dynamically Positioned ships, ferries, gas and car carriers, tugboats, barges and dredgers.
In theory, shipping can have a low impact on the environment. It is safe and profitible for economies around the world. However, serious problems occur with the shipping of oil, dumping of waste water into the ocean, chemical accidents at sea, and the inevitable air and water pollution occuring when modern day engines are used. Ships release air pollutants in the form of sulphur dioxide, nitrogen oxides, carbon dioxide, hydrocarbons and carbon monoxide. Chemicals dumped in the ocean from ships include chemicals from the ship itself, cleaning chemicals for machine parts, and cleaning supplies for living quarters. Large amounts of chemicals are often spilled into the ocean and sewage is not always treated properly or treated at all. Alien species riding in the ballast water of ships arrive in great numbers to crash native ecosystems and garbage is dumped over the side of many vessels. Dangerous industrial waste and harmful substances like halogenated hydrocarbons, water treatment chemicals, and antifouling paints are also dumped frequently. Ships and other watercraft with engines disturb the natural environment with loud noises, large waves, frequently striking and killing animals like manatees and dolphins.
Tourism
Tourism is the fastest growing division of the world economy and is responsible for more than 200 million jobs all over the world. In the US alone, tourism resulted in an economic gain of 478 billion dollars. With 700 million people traveling to another country in the year 2000, tourism is in the top five economic contributors to 83% of all countries and the most important economy for 38% of countries. The tourism industry is based on natural resources present in each country and usually negatively affect ecosystems because it is often left unmanaged. However, sustainable tourism can actually promote conservation of the environment.
The negative effects of tourism originate from the development of coastal habitats and the annihilation of entire ecosystems like mangroves, coral reefs, wetlands and estuaries. Garbage and sewage generated by visitors can add to the already existing solid waste and garbage disposal issues present in many communities. Often visitors produce more waste than locals, and much of it ends up as untreated sewage dumped in the ocean. The ecosystem must cope with eutrophication, or the loss of oxygen in the water due to excessive algal bloom as well as disease epidemics. Sewage can be used as reclaimed water to treat lawns so that fertilizers and pesticides do not seep into the ocean.
Other problems with tourism include the overexploitation of local seafood, the destruction of local habitats through careless scuba diving or snorkeling and the dropping of anchors on underwater features. Ecotourism and cultural tourism are a new trend that favors low impact tourism and fosters a respect for local cultures and ecosystems.
Mining
Humans began to mine the ocean floor for diamonds, gold, silver, metal ores like manganese nodules and gravel mines in the 1950s when the company, Tidal Diamonds, was established by Sam Collins. Diamonds are found in greater number and quality in the ocean than on land but are much harder to mine. When diamonds are mined, the ocean floor is dredged to bring it up to the boat and sift through the sediment for valuable gems. The process is difficult sediment is not easy to bring up to the surface but will probably become a huge industry once technology evolves to solve the logistical problem.
Metal compounds, gravels, sands and gas hydrates are also mined in the ocean. Mining of manganese nodules containing nickel, copper and cobalt began in the 1960’s and soon after it was discovered that Papua New Guinea was one of the few places where nodules were located in shallow waters rather than deep waters. Although manganese nodules could be found in shallow waters in significant quantities, the expense of bringing the ore up to the surface proved to be expensive. Sands and gravels are often mined for in the United States and are used to protect beaches and reduce the effects of erosion.
Mining the ocean can be devastating to the natural ecosystems. Dredging of any kind pulls up the ocean floor resulting in widespread destruction of marine animal habitats as well as wiping out vast numbers of fishes and invertebrates. When the ocean floor is mined, a cloud of sediment rises up in the water interfering with photosynthetic processes of phytoplankton and other marine life in addition to introducing previously benign heavy metals into the food chain. As minerals found on land are exploited and used up, mining of the ocean floor will increase.
Climate Buffer
The ocean is an integral component of the world’s climate due to its capacity to collect, drive and mix water, heat and carbon dioxide. The ocean can hold and circulate more water, heat and carbon dioxide than the atmosphere although the components of the Earth’s climate are constantly exchanged. Because the ocean can store so much heat, seasons occur later than they would and air above the ocean is warmed. Heat energy stored in the ocean in one season will affect the climate almost an entire season later. The ocean and the atmosphere work together to form complex weather phenomena like the North Atlantic Oscillation and El Nino. The ocean could also buffer events like the greenhouse effect or global warming, holding the heat energy for long periods of time to be released at a later date. The many chemical cycles occurring between the ocean and the atmosphere also influence the climate by controlling the amount of radiation released into ecosystems and our environment.
The atmosphere directly above the ocean does not absorb much heat by itself, so in order for it to warm up, the temperature of the ocean has to rise first. The two other ways for the atmosphere to warm near the ocean are by reflection of light off of the surface of the ocean or by the evaporation of water from the ocean surface. The temperature of the ocean controls the climate in the lower part of the atmosphere; so for most areas of the Earth the ocean temperature is responsible for the air temperature.
The main forms of climate buffering by the ocean are by the transport of heat through ocean currents traveling across huge basins. Areas like the tropics end up being cooled and higher latitudes are warmed by this effect. Air temperatures worldwide are regulated by the circulation of heat by the oceans. The ocean stores heat in the upper two meters of the photic zone. This is possible because seawater has a very high density and specific heat and can store vast quantities of energy in the form of heat. The ocean can then buffer changes in temperature by storing heat and releasing heat. Evaporation cools ocean water which cools the atmosphere. It is most noticeable near the equator and the effect decreases closer to the poles.
Oxygen Production
Gases in the atmosphere like carbon, nitrogen, sulfur and oxygen are dissolved through the water cycle. The gases that are now crucial to all ecosystems and biological processes originally came from the inside layers of the earth during the period when the earth was first formed. The rate of flow for oxygen (as well as other gases) is controlled by biological processes, especially metabolism of organisms like prokaryotes and bacteria. Prokaryotes have been around since the beginning of the Earth, have evolved to be able to use chemical energy to create organic matter and are capable of both reducing and oxidizing inorganic compounds. Bacteria that can reduce inorganic compounds are anaerobic and those that oxidize inorganic compounds are aerobic. Aerobic bacteria release oxygen as a by-product of photosynthesis.
Approximately 2 billion years ago, aerobic bacteria began producing oxygen which gradually filled up all of the oxygen reservoirs in the environment. Once these “sinks” were filled, molecular oxygen began to build in the atmosphere, creating an environment favorable for other life to inhabit the Earth. Sinks included reduced iron ions and hydrogen sulfide gas. Evidence of this process can be found in the banded iron formations created when iron minerals were precipitated. The oxygen started to fill the atmosphere up and new bacteria evolved that could use oxygen to oxidize both inorganic and organic compounds. Bacteria that were accustomed to an oxygen-poor atmosphere only survived in anaerobic environments like sewage, swamps, and in the sediments of both marine and freshwater areas.
Phytoplankton account for possibly 90% of the world’s oxygen production because water covers about 70% of the Earth and phytoplankton are abundant in the photic zone of the surface layers. Some of the oxygen produced by phytoplankton is absorbed by the ocean, but most flows into the atmosphere where it becomes available for oxygen dependent life forms.
Wednesday, 23 February 2011
DUMPING GROUND
SEA AS DUMPING GROUND
Runoff and Pollution
Although the ocean covers two-thirds of the surface of the Earth, it is surprisingly vulnerable to human influences such as overfishing, pollution from run-off, and dumping of waste from human activity. This kind of pollution can have serious economic and health impacts by killing marine life and damaging habitats and ecosystems. Toxins from pesticides, fertilizers, and other chemicals used on farms contaminate nearby rivers that flow into the ocean, which can cause extensive loss of marine life in bays and estuaries leading to the creation of dead zones. The dumping of industrial, nuclear and other waste into oceans was legal until the early 1970s when it became regulated; however dumping still occurs illegally everywhere.
Ocean Dumping
Governments world-wide were urged by the 1972 Stockholm Conference to control the dumping of waste in their oceans by implementing new laws. The United Nations met in London after this recommendation to begin the Convention on the Prevention of Marine Pollution by Dumping of Wastes and Other Matter which was implemented in 1975. The International Maritime Organization was given responsibility for this convention and a Protocol was finally adopted in 1996, a major step in the regulation of ocean dumping.
Waste in the Ocean
The most toxic waste material dumped into the ocean includes dredged material, industrial waste, sewage sludge, and radioactive waste. Dredging contributes about 80% of all waste dumped into the ocean adding up to several million tons of material dumped each year. Rivers, canals, and harbors are dredged to remove silt and sand build up or to establish new waterways. About 20-22% of dredged material is dumped into the ocean. The remainder is dumped into other waters or landfills and some is used for development. About 10% of all dredged material is polluted with heavy metals such as cadmium, mercury, and chromium; hydrocarbons such as heavy oils; nutrients including phosphorous and nitrogen; and organochlorines from pesticides. Waterways and therefore silt and sand accumulate these toxins from land runoff, shipping practices, industrial and community waste, and other sources. When these materials find their way into the ocean, marine organisms suffer toxic effects and seafood is often contaminated
Runoff and Pollution
Although the ocean covers two-thirds of the surface of the Earth, it is surprisingly vulnerable to human influences such as overfishing, pollution from run-off, and dumping of waste from human activity. This kind of pollution can have serious economic and health impacts by killing marine life and damaging habitats and ecosystems. Toxins from pesticides, fertilizers, and other chemicals used on farms contaminate nearby rivers that flow into the ocean, which can cause extensive loss of marine life in bays and estuaries leading to the creation of dead zones. The dumping of industrial, nuclear and other waste into oceans was legal until the early 1970s when it became regulated; however dumping still occurs illegally everywhere.
Ocean Dumping
Governments world-wide were urged by the 1972 Stockholm Conference to control the dumping of waste in their oceans by implementing new laws. The United Nations met in London after this recommendation to begin the Convention on the Prevention of Marine Pollution by Dumping of Wastes and Other Matter which was implemented in 1975. The International Maritime Organization was given responsibility for this convention and a Protocol was finally adopted in 1996, a major step in the regulation of ocean dumping.
Waste in the Ocean
The most toxic waste material dumped into the ocean includes dredged material, industrial waste, sewage sludge, and radioactive waste. Dredging contributes about 80% of all waste dumped into the ocean adding up to several million tons of material dumped each year. Rivers, canals, and harbors are dredged to remove silt and sand build up or to establish new waterways. About 20-22% of dredged material is dumped into the ocean. The remainder is dumped into other waters or landfills and some is used for development. About 10% of all dredged material is polluted with heavy metals such as cadmium, mercury, and chromium; hydrocarbons such as heavy oils; nutrients including phosphorous and nitrogen; and organochlorines from pesticides. Waterways and therefore silt and sand accumulate these toxins from land runoff, shipping practices, industrial and community waste, and other sources. When these materials find their way into the ocean, marine organisms suffer toxic effects and seafood is often contaminated
ALIEN SPECIES
The introduction of non-native species to an ecosystem is one of the major causes of decreased biodiversity. Termed alien species, they are also known as exotic, introduced, non-indigenous, or invasive species. As the names imply, these species do not belong to ecosystems in which they are either intentionally or unintentionally placed. They tend to disrupt the ecosystem's balance by multiplying rapidly. These specise are often plants, fishes, mollusks, crustaceans, algae, bacteria or viruses.
Many alien species are tranferred into marine ecosystems through the ballast water transported during commercial shipping operations. Ship ballast water may transport up to 3,000 species around the world every day. Alien species are often introduced into freshwater ecosystems such as estuaries, rivers, lakes and streams by humans discarding animals or plants formerly held in captivity. In some cases, species used as bait can invade freshwater ecosystems. Well-known invasive species include the Northern Snakehead fish, the Zebra mussel, the Sea Lamprey and the Asiatic Clam, Corbicula fluminea.
Effects on Humans
The introduction of an alien species is often responsible for an increase in predation and competition, habitat reduction, a variety of diseases, extinction of native plants or animals and genetic change in populations. Certain strains of cholera have been transported in ballast water ending up in oyster beds and infecting finfish destined for the dinner table.
Alien Species Aboard
Alien species are often transported to non-native habitats in the ballast of ships. The organisms are taken in when ships attempt to balance their load by letting water into their holding tanks. When they reach their destination, the ballast water is released and with it any organisms picked up earlier. Mollusks and other organisms whose habitat includes marine substrate also attach to the surfaces ocean-going vessels at the point of departure and then fall into the water at the destination.
Unintentional introductions
Aquarium plants and animals, such as the invasive algae Caulerpa, as well as ornamental plants like the Purple loosestrife are released innocently into waterways by humans. They quickly overgrow eventually choking native plants and interfering with the water flow of lakes, rivers, estuaries, and streams. Unwanted exotic fish, such as the Red Lionfish, Pterois volitans, have invaded the waters of the Southeastern United States. The introduction of this nonnative species may cause problems becaues of its poisonous spines that divers or swimmers may be unaware of and it may also pose a risk to native species through predation or competition.
Intentional Introductions
Alien species like the Cane toad have been introduced intentionally to reduce the number of a native species in the area. Unfortunately, this plan can backfire when the animal multiples quickly and takes over the habitat and beyond. In Hawaii, for example, the Mongoose has eliminated many species of birds but it was originally introduced to keep the rat population down. The kudzu plant that blankets much of the southern United States was the result of a program sponsored by the government to control erosion.
Many alien species are tranferred into marine ecosystems through the ballast water transported during commercial shipping operations. Ship ballast water may transport up to 3,000 species around the world every day. Alien species are often introduced into freshwater ecosystems such as estuaries, rivers, lakes and streams by humans discarding animals or plants formerly held in captivity. In some cases, species used as bait can invade freshwater ecosystems. Well-known invasive species include the Northern Snakehead fish, the Zebra mussel, the Sea Lamprey and the Asiatic Clam, Corbicula fluminea.
Effects on Humans
The introduction of an alien species is often responsible for an increase in predation and competition, habitat reduction, a variety of diseases, extinction of native plants or animals and genetic change in populations. Certain strains of cholera have been transported in ballast water ending up in oyster beds and infecting finfish destined for the dinner table.
Alien Species Aboard
Alien species are often transported to non-native habitats in the ballast of ships. The organisms are taken in when ships attempt to balance their load by letting water into their holding tanks. When they reach their destination, the ballast water is released and with it any organisms picked up earlier. Mollusks and other organisms whose habitat includes marine substrate also attach to the surfaces ocean-going vessels at the point of departure and then fall into the water at the destination.
Unintentional introductions
Aquarium plants and animals, such as the invasive algae Caulerpa, as well as ornamental plants like the Purple loosestrife are released innocently into waterways by humans. They quickly overgrow eventually choking native plants and interfering with the water flow of lakes, rivers, estuaries, and streams. Unwanted exotic fish, such as the Red Lionfish, Pterois volitans, have invaded the waters of the Southeastern United States. The introduction of this nonnative species may cause problems becaues of its poisonous spines that divers or swimmers may be unaware of and it may also pose a risk to native species through predation or competition.
Intentional Introductions
Alien species like the Cane toad have been introduced intentionally to reduce the number of a native species in the area. Unfortunately, this plan can backfire when the animal multiples quickly and takes over the habitat and beyond. In Hawaii, for example, the Mongoose has eliminated many species of birds but it was originally introduced to keep the rat population down. The kudzu plant that blankets much of the southern United States was the result of a program sponsored by the government to control erosion.
HABITAT POBLEM
The Problem
Habitat destruction is a huge problem in the marine environment. Habitats are destroyed by:
Destructive fishing activity: bottom trawling and dynamiting coral reefs destroy entire ecosystems.
Coastal development: habitats are destroyed when marshes are dredged for real estate development. Soil runoff and erosion result in excess nutrients from fertilizers and domestic sewage, which then leads to harmful algae blooms that block sunlight and deplete the water of oxygen. It also causes silt to build-up on coral reefs, which blocks sunlight necessary for coral to grow.
Pollution: development near coastal waters contaminates the Ocean with toxic substances, such as industrial chemicals, pesticides, and motor oil.
Dredging ship channels: Removes accumulated sediment and pollutants re-suspending them into the water. Dredging can also destroy sea grass beds and other habitats that provide food, shelter, and breeding grounds. The dredged material must be disposed of, and is often dumped into salt marshes damaging a very productive marine habitat.
Solutions
Marine Protected Areas (MPAs): marine sites such as sanctuaries, fisheries management areas, state conservation areas, and wildlife refuges established to protect habitats, endangered species, and to restore the health of marine ecosystems in areas jeopardized by habitat and species loss.
Marine Reserves: marine sites that provide a higher degree of ecosystem protection by prohibiting fishing, mineral extraction, and other habitat-altering activities. Marine Reserves are far more effective than MPAs, but unfortunately they are not as common
Land use and development regulation: An integrated approach to land use and management based on scientific knowledge is needed to protect coastal areas. Policy makers need to be informed on the impact coastal development is having on marine habitats through accessible and evidence-based information.
Monitoring and reporting: some conservation efforts are empowering the citizens with the responsibility for monitoring water quality in their coastal communities through sampling and testing, photographing fouled areas, and providing information to local policy makers for action.
Zoning: related to integrated land use and development management, zoning coastal areas into MPAs, Marine Reserves, approved fishing areas, with varying levels of use has the potential to slow some of the habitat degradation caused by development. The Great Barrier Reef is managed in this way. Through cooperation among local, state, and national governments, this approach may provide a viable solution to all stakeholders from tourists, to the fishing industry, to conservation efforts etc.
Although habitat destruction has been increasing for many years, the protection of marine habitats has only recently become an issue of critical importance to conservation efforts, local and national governments, and international marine conservation groups. The Ocean's invulnerability to human activity is now being realized as a myth. Coastal regions are still experiencing intense pressure by exploding coastal populations; however there are solutions at hand to prevent further damage from occurring.
Everyone knows that the Northern Spotted Owl is threatened because of destruction to the forests of the Pacific Northwest - but what will happen to the Pacific Seahorse if its habitat continues to decline? Due to the lack of a strong public sea ethic marine life doesn't appear on the conservation radar screen as much as its terrestrial counterparts, but ocean habitats are in decline as well, and therefore the creatures they support are too (which in turn support us). Most marine habitat destruction is caused by pollution, commercial fishing equipment, coastal development, and other human activity. Much of it can be avoided with simple measures
Habitat destruction is a huge problem in the marine environment. Habitats are destroyed by:
Destructive fishing activity: bottom trawling and dynamiting coral reefs destroy entire ecosystems.
Coastal development: habitats are destroyed when marshes are dredged for real estate development. Soil runoff and erosion result in excess nutrients from fertilizers and domestic sewage, which then leads to harmful algae blooms that block sunlight and deplete the water of oxygen. It also causes silt to build-up on coral reefs, which blocks sunlight necessary for coral to grow.
Pollution: development near coastal waters contaminates the Ocean with toxic substances, such as industrial chemicals, pesticides, and motor oil.
Dredging ship channels: Removes accumulated sediment and pollutants re-suspending them into the water. Dredging can also destroy sea grass beds and other habitats that provide food, shelter, and breeding grounds. The dredged material must be disposed of, and is often dumped into salt marshes damaging a very productive marine habitat.
Solutions
Marine Protected Areas (MPAs): marine sites such as sanctuaries, fisheries management areas, state conservation areas, and wildlife refuges established to protect habitats, endangered species, and to restore the health of marine ecosystems in areas jeopardized by habitat and species loss.
Marine Reserves: marine sites that provide a higher degree of ecosystem protection by prohibiting fishing, mineral extraction, and other habitat-altering activities. Marine Reserves are far more effective than MPAs, but unfortunately they are not as common
Land use and development regulation: An integrated approach to land use and management based on scientific knowledge is needed to protect coastal areas. Policy makers need to be informed on the impact coastal development is having on marine habitats through accessible and evidence-based information.
Monitoring and reporting: some conservation efforts are empowering the citizens with the responsibility for monitoring water quality in their coastal communities through sampling and testing, photographing fouled areas, and providing information to local policy makers for action.
Zoning: related to integrated land use and development management, zoning coastal areas into MPAs, Marine Reserves, approved fishing areas, with varying levels of use has the potential to slow some of the habitat degradation caused by development. The Great Barrier Reef is managed in this way. Through cooperation among local, state, and national governments, this approach may provide a viable solution to all stakeholders from tourists, to the fishing industry, to conservation efforts etc.
Although habitat destruction has been increasing for many years, the protection of marine habitats has only recently become an issue of critical importance to conservation efforts, local and national governments, and international marine conservation groups. The Ocean's invulnerability to human activity is now being realized as a myth. Coastal regions are still experiencing intense pressure by exploding coastal populations; however there are solutions at hand to prevent further damage from occurring.
Everyone knows that the Northern Spotted Owl is threatened because of destruction to the forests of the Pacific Northwest - but what will happen to the Pacific Seahorse if its habitat continues to decline? Due to the lack of a strong public sea ethic marine life doesn't appear on the conservation radar screen as much as its terrestrial counterparts, but ocean habitats are in decline as well, and therefore the creatures they support are too (which in turn support us). Most marine habitat destruction is caused by pollution, commercial fishing equipment, coastal development, and other human activity. Much of it can be avoided with simple measures
HABITAT CONSERVATION
Habitat conservation for wild species is one of the most important issues facing the environment today - both in the ocean and on land. As human populations increase, land use increases, and wild species have smaller spaces to call home. More than half of Earth's terrestrial surface has been altered due to human activity, resulting in drastic deforestation, erosion and loss of topsoil, biodiversity loss, and extinction. Species cannot survive outside of their natural habitat without human intervention, such as the habitats found in a zoo or aquarium for example. Preserving habitats is essential to preserving biodiversity. Migratory species are particularly vulnerable to habitat destruction because they tend to inhabit more than one natural habitat. This creates the need to not only preserve the two habitats for migratory species, but also their migratory route. Altering a natural habitat even slightly can result in a domino effect that harms the entire ecosystem.
Thursday, 17 February 2011
THE ENDANGERED SPECIES LIST
Marine mammals
Marine mammals close to becoming an endangered species are categorized under threatened. These include: Eastern Stock of the Steller sea lion, Guadalupe fur seal, and the California sea Otter.
According to the Marine Mammal Protection Act or MMPA, species can also be called “depleted”. A depleted species is one whose numbers have dropped lower than the optimum sustainable population or OSP. The OSP is determined by whether the animals are reproducing in a healthy number that corresponds to the carrying capacity of the environment. When it is determined that a species has been depleted, the NMFS comes up with a plan to research factors involved and to bring the numbers back. Animals considered depleted are the North Atlantic Coastal bottlenose dolphin, the Eastern spinner dolphin, North Pacific fur seal, the Northeastern Offshore and Coastal spotted dolphins, and the Cook Inlet beluga whale. More information is being collected on “species of concern” which include the Cook Inlet Beluga whale and the orca (killer whale). The Eastern Pacific gray whale has been recovered by the Endangered Species Act and was actually taken off the list. The Steller’s Sea cow was lost forever shortly before the MMPA and ESA were implemented.
Pinnipeds are seals, sea lions or walruses but are taxonomically relatives of bears, dogs, raccoons, otters or weasels. The families under pinnipedia include Phocidae, Otariidae and Odobenidae which are earless seals, fur seals or sea lions, and walrus respectively. The main reason for the loss of many pinnipeds is the amount of commercial fishing that took place from the 1700's up to the 1900's. Other reasons include the development of coastline and lack of fish due to overfishing.
Another group of marine mammals affected by commercial hunting between the 1700's and the 1900's were the baleen whales. Populations of baleen whales are still low in numbers even though commercial hunting is now mostly illegal. Many whales are still being hit and killed by ships, particularly the critically endangered northern right whale. Whales are also tangled in fishing gear or marine garbage. Sometimes something as small as a party balloon can kill a whale by cutting off its digestive tract.
Marine invertebrates
Marine invertebrates and plants are currently listed under the “candidates or species of concern” category in the Endangered Species Act due to a lack of information or time. These include Brachiopods, Corals, Mollusks, and various plant life. Brachiopods are invertebrates that live on the seafloor and feed through a filter appendage. They are attached to objects in the ocean and resemble a clam. Brachiopods reached the peak of their numbers in the Paleozoic era and were reduced greatly during the Permo-Triassic mass extinction. The two classes or types of brachiopods are the Inarticulata and the Articulata. Reasons for decline in number of brachiopods include habitat destruction, overfishing, pollution and sediment accumulation, general vulnerability to stress, and small numbers.
Corals are made of invertebrate polyps and are either hard or soft. They have been around for 500 million years since the Cambrian period. Hard corals are composed of calcium carbonate and they live symbiotically with zooxanthellae, a type of phytoplankton. Soft corals have calcareous pieces of matter in their structure and are usually found independently in deeper waters. All corals are related to anemones, hydras or jellyfish. There is only one class of coral and that is Anthozoa. Subclasses include Alcyonaria, Ceriantipatharia, Hexacorallia, and Zoantharia. In consideration for endangered status are the Elkhorn coral, Staghorn, Ivory-bush, and Hawaiian reef corals (Order Scleractinia). Corals have declined drastically in numbers due to disease epidemics since the 80's, destruction of habitat, accumulation of sediment, a changing food chain resulting in increased predation, hurricanes, pollutants, alien species, invasive species like green algae, small numbers, fishing practices, and bleaching of corals due to temperature changes (and more).
Mollusks are invertebrates and most of them are in the Class Gastropoda which means stomach foot in Latin. They have a soft body are often found with a shell although they can also have an internal shell or no shell. Related to segmented worms and pogonophora, there are seven Classes of mollusks including Aplacophora, Bivalvia, Cephalopoda, Gastropoda, Monoplacophora, Polyplacophora, and Scaphopoda. Animals qualifying as species of concern include: black abalone, green abalone, pink abalone, and pinto abalone. The white abalone is currently classified as endangered. The abalone has been overfished, numbers decreased, genetic diversity has been lost, it has been subjected to disease, poachers and changes in the food chain resulting in an increase in predation.
Marine Plants
Most marine plants include types of seagrass, types of mangroves and types of algae. Mangroves and seagrasses are flowering plants and use pollen to reproduce. They are often found close to the coast. Algae can be anything from tiny phytoplankton to huge seaweeds. So far, Johnson’s seagrass is listed as threatened although many other plants should be on the list. Plants are mostly lost when humans change the habitat, natural events change the environment or oxygen is used up by organisms thriving in nutrient enriched areas (caused by humans).
Sea Turtles
Sea turtles are another animal threatened by extinction in the oceans. With aerodynamic bodies, oversized flippers and the ability to breathe air, these unique animals live in tropical or subtropical oceans all over the planet. The United States is visited by 6 of the 7 types of sea turtles including the green, hawksbill, Kemp's ridley, leatherback, loggerhead and the olive ridley. Sea turtles rely on undisturbed beaches to lay eggs and can travel huge distances to feed or nest.
The green turtle is endangered or threatened, the hawksbill turtle is endangered, Kemp's ridley turtle is endangered, the leatherback turtle is endangered, the loggerhead turtle is threatened, and the olive ridley turtle is endangered or threatened. The NOAA fisheries are primarily in charge of the conservation and restoration of these species although the U.S. Fish and Wildlife Service shares jurisdiction.
The major reasons why sea turtles are declining in numbers include development or destruction of nesting and foraging places, accidental tangling in nets or lines, tangling in marine garbage and being hit by boats or motor craft. Regulations on gillnets, longlines, pound nets and trawls have been established by the NOAA fisheries and certain areas crucial for sea turtles have been roped off at important times. It is also important to handle sea turtles in a certain way and there are now regulations for this as well. Comprehensive strategies, research and management efforts are in the process of being developed so that the sea turtle can recover. In addition to nation-wide programs, the NOAA also has national and international programs.
Marine and anadromous fish
Marine and anadromous (born in fresh water first) fish are also under protection by the NOAA. Anadromous fish start out in freshwater, go to salt water and then return to freshwater. Marine fish spend their entire lives in salt water. Most fish listed under the Endangered Species Act are Pacific salmonids and have been listed as Evolutionary Significant Units. Other types of fish listed are Atlantic salmon, shortnose sturgeon, smalltooth sawfish and the Gulf sturgeon.
Marine mammals close to becoming an endangered species are categorized under threatened. These include: Eastern Stock of the Steller sea lion, Guadalupe fur seal, and the California sea Otter.
According to the Marine Mammal Protection Act or MMPA, species can also be called “depleted”. A depleted species is one whose numbers have dropped lower than the optimum sustainable population or OSP. The OSP is determined by whether the animals are reproducing in a healthy number that corresponds to the carrying capacity of the environment. When it is determined that a species has been depleted, the NMFS comes up with a plan to research factors involved and to bring the numbers back. Animals considered depleted are the North Atlantic Coastal bottlenose dolphin, the Eastern spinner dolphin, North Pacific fur seal, the Northeastern Offshore and Coastal spotted dolphins, and the Cook Inlet beluga whale. More information is being collected on “species of concern” which include the Cook Inlet Beluga whale and the orca (killer whale). The Eastern Pacific gray whale has been recovered by the Endangered Species Act and was actually taken off the list. The Steller’s Sea cow was lost forever shortly before the MMPA and ESA were implemented.
Pinnipeds are seals, sea lions or walruses but are taxonomically relatives of bears, dogs, raccoons, otters or weasels. The families under pinnipedia include Phocidae, Otariidae and Odobenidae which are earless seals, fur seals or sea lions, and walrus respectively. The main reason for the loss of many pinnipeds is the amount of commercial fishing that took place from the 1700's up to the 1900's. Other reasons include the development of coastline and lack of fish due to overfishing.
Another group of marine mammals affected by commercial hunting between the 1700's and the 1900's were the baleen whales. Populations of baleen whales are still low in numbers even though commercial hunting is now mostly illegal. Many whales are still being hit and killed by ships, particularly the critically endangered northern right whale. Whales are also tangled in fishing gear or marine garbage. Sometimes something as small as a party balloon can kill a whale by cutting off its digestive tract.
Marine invertebrates
Marine invertebrates and plants are currently listed under the “candidates or species of concern” category in the Endangered Species Act due to a lack of information or time. These include Brachiopods, Corals, Mollusks, and various plant life. Brachiopods are invertebrates that live on the seafloor and feed through a filter appendage. They are attached to objects in the ocean and resemble a clam. Brachiopods reached the peak of their numbers in the Paleozoic era and were reduced greatly during the Permo-Triassic mass extinction. The two classes or types of brachiopods are the Inarticulata and the Articulata. Reasons for decline in number of brachiopods include habitat destruction, overfishing, pollution and sediment accumulation, general vulnerability to stress, and small numbers.
Corals are made of invertebrate polyps and are either hard or soft. They have been around for 500 million years since the Cambrian period. Hard corals are composed of calcium carbonate and they live symbiotically with zooxanthellae, a type of phytoplankton. Soft corals have calcareous pieces of matter in their structure and are usually found independently in deeper waters. All corals are related to anemones, hydras or jellyfish. There is only one class of coral and that is Anthozoa. Subclasses include Alcyonaria, Ceriantipatharia, Hexacorallia, and Zoantharia. In consideration for endangered status are the Elkhorn coral, Staghorn, Ivory-bush, and Hawaiian reef corals (Order Scleractinia). Corals have declined drastically in numbers due to disease epidemics since the 80's, destruction of habitat, accumulation of sediment, a changing food chain resulting in increased predation, hurricanes, pollutants, alien species, invasive species like green algae, small numbers, fishing practices, and bleaching of corals due to temperature changes (and more).
Mollusks are invertebrates and most of them are in the Class Gastropoda which means stomach foot in Latin. They have a soft body are often found with a shell although they can also have an internal shell or no shell. Related to segmented worms and pogonophora, there are seven Classes of mollusks including Aplacophora, Bivalvia, Cephalopoda, Gastropoda, Monoplacophora, Polyplacophora, and Scaphopoda. Animals qualifying as species of concern include: black abalone, green abalone, pink abalone, and pinto abalone. The white abalone is currently classified as endangered. The abalone has been overfished, numbers decreased, genetic diversity has been lost, it has been subjected to disease, poachers and changes in the food chain resulting in an increase in predation.
Marine Plants
Most marine plants include types of seagrass, types of mangroves and types of algae. Mangroves and seagrasses are flowering plants and use pollen to reproduce. They are often found close to the coast. Algae can be anything from tiny phytoplankton to huge seaweeds. So far, Johnson’s seagrass is listed as threatened although many other plants should be on the list. Plants are mostly lost when humans change the habitat, natural events change the environment or oxygen is used up by organisms thriving in nutrient enriched areas (caused by humans).
Sea Turtles
Sea turtles are another animal threatened by extinction in the oceans. With aerodynamic bodies, oversized flippers and the ability to breathe air, these unique animals live in tropical or subtropical oceans all over the planet. The United States is visited by 6 of the 7 types of sea turtles including the green, hawksbill, Kemp's ridley, leatherback, loggerhead and the olive ridley. Sea turtles rely on undisturbed beaches to lay eggs and can travel huge distances to feed or nest.
The green turtle is endangered or threatened, the hawksbill turtle is endangered, Kemp's ridley turtle is endangered, the leatherback turtle is endangered, the loggerhead turtle is threatened, and the olive ridley turtle is endangered or threatened. The NOAA fisheries are primarily in charge of the conservation and restoration of these species although the U.S. Fish and Wildlife Service shares jurisdiction.
The major reasons why sea turtles are declining in numbers include development or destruction of nesting and foraging places, accidental tangling in nets or lines, tangling in marine garbage and being hit by boats or motor craft. Regulations on gillnets, longlines, pound nets and trawls have been established by the NOAA fisheries and certain areas crucial for sea turtles have been roped off at important times. It is also important to handle sea turtles in a certain way and there are now regulations for this as well. Comprehensive strategies, research and management efforts are in the process of being developed so that the sea turtle can recover. In addition to nation-wide programs, the NOAA also has national and international programs.
Marine and anadromous fish
Marine and anadromous (born in fresh water first) fish are also under protection by the NOAA. Anadromous fish start out in freshwater, go to salt water and then return to freshwater. Marine fish spend their entire lives in salt water. Most fish listed under the Endangered Species Act are Pacific salmonids and have been listed as Evolutionary Significant Units. Other types of fish listed are Atlantic salmon, shortnose sturgeon, smalltooth sawfish and the Gulf sturgeon.
ENDANGERED SPECIES ACT
The Endangered Species Act
The Endangered Species Preservation Act of 1966 was established in the U.S. to protect species facing possible extinction, but it only covers native species and the extent to which they are protected is extremely limited. In 1969, the Departments of the Interior, Agriculture, and Defense passed the Endangered Species Conservation Act to prevent a mass extinction event in certain species. The use of endangered species by humans for food, fur, and other commercial uses was outlawed by this act and by the Marine Mammal Protection Act of 1972. In 1973, the Convention on International Trade in Endangered Species (CITES) of Wild Fauna and Flora was implemented to cut back on the trade of plants and animals in trouble. The 1973 Endangered Species Act is one of the most significant environmental laws in America and defines endangered or threatened species, puts plants and invertebrates under protection, requires federal agencies to start programs to conserve important habitats, creates a wide umbrella of laws against hunting for endangered species, and matches contributions from individual states towards the project. The United States Fish and Wildlife Service (FWS) and the National Marine Fisheries Service (NMFS) are responsible for the enforcement of the Endangered Species Act.
Scientific Research
Scientists and the general population are also worried that if the destruction of biodiversity continues at the current rate, a mass extinction event will eventually take place. Many species go extinct before there is time to save them. Without protection, resources like global fisheries and future medicines may be lost forever unless adequate policy, scientific research, and individual actions can prevent further loss.
The Endangered Species Preservation Act of 1966 was established in the U.S. to protect species facing possible extinction, but it only covers native species and the extent to which they are protected is extremely limited. In 1969, the Departments of the Interior, Agriculture, and Defense passed the Endangered Species Conservation Act to prevent a mass extinction event in certain species. The use of endangered species by humans for food, fur, and other commercial uses was outlawed by this act and by the Marine Mammal Protection Act of 1972. In 1973, the Convention on International Trade in Endangered Species (CITES) of Wild Fauna and Flora was implemented to cut back on the trade of plants and animals in trouble. The 1973 Endangered Species Act is one of the most significant environmental laws in America and defines endangered or threatened species, puts plants and invertebrates under protection, requires federal agencies to start programs to conserve important habitats, creates a wide umbrella of laws against hunting for endangered species, and matches contributions from individual states towards the project. The United States Fish and Wildlife Service (FWS) and the National Marine Fisheries Service (NMFS) are responsible for the enforcement of the Endangered Species Act.
Scientific Research
Scientists and the general population are also worried that if the destruction of biodiversity continues at the current rate, a mass extinction event will eventually take place. Many species go extinct before there is time to save them. Without protection, resources like global fisheries and future medicines may be lost forever unless adequate policy, scientific research, and individual actions can prevent further loss.
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