Overfishing aff inherency
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- Bio D is important to keep the ecosystems that humans depend on functioning
- Biodiversity risks full ecosystem collapse- it means no species in the food chain can adapt and survive
- Biodiversity critical to prevent species loss—no adaptation
- Fish are becoming scarce due to overfishing, threatening biodiversity
Bio-D ImpactDestruction of aquatic ecosystems leads to extinction Craig 3 (Robin, Associate Professor of Law at Indiana, Winter, 34 McGeorge L. Review. 155) Biodiversity and ecosystem function arguments for conserving marine ecosystems also exist, just as they do for terrestrial ecosystems, but these arguments have thus far rarely been raised in political debates. For example, besides significant tourism values - the most economically valuable ecosystem service coral reefs provide, worldwide - coral reefs protect against storms and dampen other environmental fluctuations, services worth more than ten times the reefs’ value for food production. Waste treatment is another significant, non-extractive ecosystem function that intact coral reef ecosystems provide. More generally, “ocean ecosystems play a major role in the global geochemical cycling of all the elements that represent the basic building blocks of living organisms, carbon, nitrogen, oxygen, phosphorus, and sulfur, as well as other less abundant but necessary elements.” In a very real and direct sense, therefore, human degradation of marine ecosystems impairs the planet’s ability to support life. Maintaining biodiversity is often critical to maintaining the functions of marine ecosystems. Current evidence shows that, in general, an ecosystem’s ability to keep functioning in the face of disturbance is strongly dependent on its biodiversity, “indicating that more diverse ecosystems are more stable.” Coral reef ecosystems are particularly dependent on their biodiversity. Most ecologists agree that the complexity of interactions and degree of interrelatedness among component species is higher on coral reefs than in any other marine environment. This implies that the ecosystem functioning that produces the most highly valued components is also complex and that many otherwise insignificant species have strong effects on sustaining the rest of the reef system. Thus, maintaining and restoring the biodiversity of marine ecosystems is critical to maintaining and restoring the ecosystem services that they provide. Non-use biodiversity values for marine ecosystems have been calculated in the wake of marine disasters, like the Exxon Valdez oil spill in Alaska. Similar calculations could derive preservation values for marine wilderness. However, economic value, or economic value equivalents, should not be “the sole or even primary justification for conservation of ocean ecosystems. Ethical arguments also have considerable force and merit.” At the forefront of such arguments should be a recognition of how little we know about the sea - and about the actual effect of human activities on marine ecosystems. The United States has traditionally failed to protect marine ecosystems because it was difficult to detect anthropogenic harm to the oceans, but we now know that such harm is occurring - even though we are not completely sure about causation or about how to fix every problem. Ecosystems like the NWHI coral reef ecosystem should inspire lawmakers and policymakers to admit that most of the time we really do not know what we are doing to the sea and hence should be preserving marine wilderness whenever we can - especially when the United States has within its territory relatively pristine marine ecosystems that may be unique in the world. We may not know much about the sea, but we do know this much: if we kill the ocean we kill ourselves, and we will take most of the biosphere with us. The Black Sea is almost dead, its once-complex and productive ecosystem almost entirely replaced by a monoculture of comb jellies, “starving out fish and dolphins, emptying fishermen’s nets, and converting the web of life into brainless, wraith-like blobs of jelly.” More importantly, the Black Sea is not necessarily unique. The Black Sea is a microcosm of what is happening to the ocean systems at large. The stresses piled up: overfishing, oil spills, industrial discharges, nutrient pollution, wetlands destruction, the introduction of an alien species. The sea weakened, slowly at first, then collapsed with shocking suddenness. The lessons of this tragedy should not be lost to the rest of us, because much of what happened here is being repeated all over the world. The ecological stresses imposed on the Black Sea were not unique to communism. Nor, sadly, was the failure of governments to respond to the emerging crisis. Oxygen-starved “dead zones” appear with increasing frequency off the coasts of major cities and major rivers, forcing marine animals to flee and killing all that cannot. Ethics as well as enlightened self-interest thus suggest that the United States should protect fully-functioning marine ecosystems wherever possible - even if a few fishers go out of business as a result Biodiversity loss has impacts comparable to climate change and pollution at their worst, reduces plant growth and productivityErickson ’12 (Jim, professor of environmental studies at the University of Michigan, 5/2/12, Ecosystem effects of biodiversity loss could rival impacts of climate change, pollution, Michigan News, University of Michigan, http://ns.umich.edu/new/multimedia/slideshows/20366-ecosystem-effects-of-biodiversity-loss-could-rival-impacts-of-climate-change-pollution?utm_source=feedburner&utm_medium=feed&utm_campaign=Feed%3A+umns-releases+(University+of+Michigan+News+Service+-+News+Releases), accessed: 7/1/14 GA) Loss of biodiversity appears to impact ecosystems as much as climate change, pollution and other major forms of environmental stress, according to a new study from an international research team. The study is the first comprehensive effort to directly compare the impacts of biological diversity loss to the anticipated effects of a host of other human-caused environmental changes. The results highlight the need for stronger local, national and international efforts to protect biodiversity and the benefits it provides, according to the researchers, who are based at nine institutions in the United States, Canada and Sweden. "Loss of biological diversity due to species extinctions is going to have major impacts on our planet, and we better prepare ourselves to deal with them," said University of Michigan ecologist Bradley Cardinale, one of the authors. The study is scheduled for online publication in the journal Nature on May 2. "These extinctions may well rank as one of the top five drivers of global change," said Cardinale, an assistant professor at the U-M School of Natural Resources and Environment and an assistant professor in the Department of Ecology and Evolutionary Biology. Studies over the last two decades have demonstrated that more biologically diverse ecosystems are more productive. As a result, there has been growing concern that the very high rates of modern extinctions – due to habitat loss, overharvesting and other human-caused environmental changes – could reduce nature's ability to provide goods and services like food, clean water and a stable climate. But until now, it's been unclear how biodiversity losses stack up against other human-caused environmental changes that affect ecosystem health and productivity. "Some people have assumed that biodiversity effects are relatively minor compared to other environmental stressors," said biologist David Hooper of Western Washington University, the lead author of the Nature paper. "Our new results show that future loss of species has the potential to reduce plant production just as much as global warming and pollution." In their study, Hooper and his colleagues used combined data from a large number of published studies to compare how various global environmental stressors affect two processes important in all ecosystems: plant growth and the decomposition of dead plants by bacteria and fungi. The new study involved the construction of a data base drawn from 192 peer-reviewed publications about experiments that manipulated species richness and examined the impact on ecosystem processes. The global synthesis by Hooper and his colleagues found that in areas where local species loss this century falls within the lower range of projections (loss of 1 to 20 percent of plant species), negligible impacts on ecosystem plant growth will result, and changes in species richness will rank low relative to the impacts projected for other environmental changes. In ecosystems where species losses fall within intermediate projections (21 to 40 percent of species), however, species loss is expected to reduce plant growth by 5 to 10 percent, an effect that is comparable in magnitude to the expected impacts of climate warming and increased ultraviolet radiation due to stratospheric ozone loss. At higher levels of extinction (41 to 60 percent of species), the impacts of species loss ranked with those of many other major drivers of environmental change, such as ozone pollution, acid deposition on forests, and nutrient pollution. "Within the range of expected species losses, we saw average declines in plant growth that were as large as changes seen in experiments simulating several other major environmental changes caused by humans," Hooper said. "I think several of us working on this study were surprised by the comparative strength of those effects." The strength of the observed biodiversity effects suggests that policymakers searching for solutions to other pressing environmental problems should be aware of potential adverse effects on biodiversity, as well, the researchers said. Still to be determined is how diversity loss and other large-scale environmental changes will interact to alter ecosystems. "The biggest challenge looking forward is to predict the combined impacts of these environmental challenges to natural ecosystems and to society," said J. Emmett Duffy of the Virginia Institute of Marine Science, a co-author of the paper. Authors of the Nature paper, in addition to Hooper, Cardinale and Duffy, are: E. Carol Adair of the University of Vermont and the National Center for Ecological Analysis and Synthesis; Jarrett E.K. Byrnes of the National Center for Ecological Analysis and Synthesis; Bruce Hungate of Northern Arizona University; Kristen Matulich of University of California Irvine; Andrew Gonzalez of McGill University; Lars Gamfeldt of the University of Gothenburg; and Mary O'Connor of the University of British Columbia and the National Center for Ecological Analysis and Synthesis. Funding for the study included grants from the National Science Foundation and the National Center for Ecological Analysis and Synthesis. "This analysis establishes that reduced biodiversity affects ecosystems at levels comparable to those of global warming or air pollution," said Henry Gholz, program director in the National Science Foundation's Division of Environmental Biology, which funded the research. Bio D is important to keep the ecosystems that humans depend on functioningLefroy 08 (E. C., “Biodiversity : Integrating Conservation and Production: Case Studies From Australian Farms, Forests and Fisheries”, Collingwood, Vic : CSIRO Publishing. 2008, EBSCO) Here is another reality. There are some ideologically driven sceptics (such as Julian Simon of the University of Maryland), but those who actually do the science estimate that extinctions are occurring in the range of 17 000 species per year (Edward Wilson’s mathematically derived 1988 estimate; Wilson 1988) to a mind-boggling estimate of an annual loss of 150 000 species (Diamond 1992). Richard I.eakey (with Roger Lewin) argues that even if we take a lower figure in this range, e.g. 30000 species per year, that is an extinction rate 120 000 times higher than the ‘normal’ or ‘background’ extinction rate, which the fossil record establishes at ‘an average of one every four years’ (Leakey & Lewin 1996). The problem is largely one of habitat loss. By the mid-1990s, 80 000 square miles of forest were falling each year (40—50% higher than a mere decade previously), with the result that only about 10% of the original tropical forest cover is still in place. By 2050 that will be reduced to a ‘tiny remnant’ (Leakey & Lewin 1996). If these trends continue, they conclude, the world stands to lose something like 50% of all species. Does this matter? Conservation biologists have always assumed that it does, and much of the burgeoning corpus of scientific literature in this area begins from this starting-point, assum ing it to be self-evident and beyond a need for defending. The literature of popular science is another matter; here, spirited explanations of the need to maintain biodiversity are much more easily located. For example, in his widely read 2005 book, Collapse: how societies choose to fail or survive, Jared Diamond notes that it is one thing to argue for the future of embattled species that are large and charismatic but much more difficult to generate a critical mass of support for the defence of species that fall below the radar of public regard. He articulates an archetypal response: “WhO cares? Do you really care less for humans than for some lousy useless little fish or weed, like the snail darter or Furbish lousewort?’ He answers the rhetorical question thus: This response misses the point that the entire natural world is made up of wild species providing for us free with services that can be very expensive, and in sorne cases impossible, for us to supply ourselves. Elimination of lots of lousy little species regularly causes big harmful consequences for humans, just as does randomly knocking out many of the lousy little rivets holding together an airplane. Here is the same argument, put by Edward O. Wilson in his popular 1998 book. Consilience: Why do we need so many species anyway ... especially since the majority are bugs, weeds and fungi? Ir is easy ro Issm iss the creepy—crawlies of the world, forgetting that less than a century ago ... native birds and mammals around the world were treated with the some callous indifference. Now the value of the little things in the natural world has become compellingly clear. Recent experimental studies on whole ecosystems support what ecologists have long suspected: The more species that live in an ecosystem. the higher its productivity and the greater its ability to withstand drought and other kinds of environmental stress. Since we depend on functioning ecosystems to cleanse our water, enrich our soil, and create the very air we breathe, biodiversity is clearly not something to discard carelessly. Biodiversity risks full ecosystem collapse- it means no species in the food chain can adapt and surviveA. S. MacDougall, K. S. McCann, G. Gellner, and R. Turkington 13 (“Diversity loss with persistent human disturbance increases vulnerability to ecosystem collapse”, Nature. 2/7/2013, Vol. 494 Issue 7435, p86-89, EBSCO) Long-term and persistent human disturbances have simultaneously altered the stability and diversity of ecological systems, with disturbances directly reducing functional attributes such as invasion resistance while eliminating the buffering effects of high species diversity’. Theory predicts that this combination of environmental change and diversity loss increases the risk of abrupt and potentially irreversible ecosystem collapse’, but long-term empirical evidence from natural systems is lacking. Here we demonstrate this relationship in a degraded but species-rich pyrogenic grassland in which the combined effects of fire suppression invasion and trophic collapse have created a species-poor grassland that Is highly productive, resilient to yearly climatic fluctuations, and resistant to invasion but vulnerable to rapid collapse after the re-Introduction o4’ fire. We initially show how human disturbance has created a negative relationship between diversity and function, contrary to theoretical predictions. Fire prevention since the mId-nineteenth century Is associated with the loss of plant species but it has stabilized high-yield annual production and invasion resistance, comparable to a managed high-yield low-diversity agricultural system. In managing for fire suppression, however, a hidden vulnerability to sudden environmental change emetEes that Is explained by the elimination of the buffering effects of high species diversity. With the re-introduction of fire, grasslands only persist In areas with remnant concentrations of native species, In which a range of rare and mostly functionally redundant plants proliferate after burning and prevent extensive invasion Including a rapid conversion towards woodland. This research shows how biodiversity can be crucial for ecosystem stability despite appearing functionally insignificant beforehand, a relationship probably applicable to many ecosystems given the globally prevalent combination of Intensive long-term land management and species loss. Biodiversity critical to prevent species loss—no adaptationA. S. MacDougall, K. S. McCann, G. Gellner, and R. Turkington 13 (“Diversity loss with persistent human disturbance increases vulnerability to ecosystem collapse”, Nature. 2/7/2013, Vol. 494 Issue 7435, p86-89, Ebsco) Biodiversity can stabilize ecological systems by functional complementarity with different species thriving under different conditions thereby buffering the effects of environmental change’. Despite an often demonstrated positive correlation between diversity and stability, however, the generality of this relationship remains unclear in natural systems, especially in those under persistent anthropogenic influences”. Human land management is often persistent, by intentional (for example, fire suppression and overfishing) or inadvertent (for example, nitrogen pollution) disturbances that homogenize both resident diversity and environmental condition. Persistent disturbances obscure diversity—stability relationships because they can affect ecosystem function independently of diversity as when overgrazing directly decreases production and provides opportunities for invasion’. Because persistent disturbances can also drive species loss, false positives may arise between diversity and ecosystem function, in which reductions in diversity and function are correlated but have weak mechanistic connections. The homogenizing effect of human activity on environmental conditions and diversity may also increase the risk of abrupt and potentially irreversible changes after disturbance pulses. even when systems appear stable beforehand’. The question of whether simpler systems are more or less resistant to disturbance has characterized diversity stability research for decade.° Recent research typically supports the latter model, but data are often derived (rom shorter-term studies in constructed experimental communities4. It is unclear, however, whether these stability-regulating mechanisms operate in a similar manner in environmentally heterogeneous natural systems, and whether all mea sures of stability respond similarly in different environmental contexts (for example, the presence or absence of disturbance). The stabilization of functional attributes after abrupt disturbances is assumed to derive from the asynchronous population-level responses of disturbance- resistant species which maintain function at the aggregate community level as disturbance-sensitive species falters. Yet in persistently managed systems characterized by the loss of environmental variability and diversity, species that are well-adapted to previous environmental conditions have often become rare or extinct. These declines may have Little functional significance as long as the existing conditions of persistent management are maintaine&4. However, this may create a hidden vulnerability to abrupt environmental change, analogous to reduced gene tic diversity limiting the capacity for adaptive responses in populations. Fish are becoming scarce due to overfishing, threatening biodiversityNuttall ’14 (Nick Nuttall, head of UNEP, Overfishing: a threat to marine biodiversity, UNEP, http://www.un.org/events/tenstories/06/story.asp?storyID=800, accessed: 7/1/14 GA) Fishing is central to the livelihood and food security of 200 million people, especially in the developing world, while one of five people on this planet depends on fish as the primary source of protein. According to UN agencies, aquaculture - the farming and stocking of aquatic organisms including fish, molluscs, crustaceans and aquatic plants - is growing more rapidly than all other animal food producing sectors. But amid facts and figures about aquaculture's soaring worldwide production rates, other, more sobering, statistics reveal that global main marine fish stocks are in jeopardy, increasingly pressured by overfishing and environmental degradation. “Overfishing cannot continue,” warned Nitin Desai, Secretary General of the 2002 World Summit on Sustainable Development, which took place in Johannesburg. “The depletion of fisheries poses a major threat to the food supply of millions of people.” The Johannesburg Plan of Implementation calls for the establishment of Marine Protected Areas (MPAs), which many experts believe may hold the key to conserving and boosting fish stocks. Yet, according to the UN Environment Programme’s (UNEP) World Conservation Monitoring Centre, in Cambridge, UK, less than one per cent of the world’s oceans and seas are currently in MPAs. The magnitude of the problem of overfishing is often overlooked, given the competing claims of deforestation, desertification, energy resource exploitation and other biodiversity depletion dilemmas. The rapid growth in demand for fish and fish products is leading to fish prices increasing faster than prices of meat. As a result, fisheries investments have become more attractive to both entrepreneurs and governments, much to the detriment of small-scale fishing and fishing communities all over the world. In the last decade, in the north Atlantic region, commercial fish populations of cod, hake, haddock and flounder have fallen by as much as 95%, prompting calls for urgent measures. Some are even recommending zero catches to allow for regeneration of stocks, much to the ire of the fishing industry. According to a Food and Agriculture Organization (FAO) estimate, over 70% of the world’s fish species are either fully exploited or depleted. The dramatic increase of destructive fishing techniques worldwide destroys marine mammals and entire ecosystems. FAO reports that illegal, unreported and unregulated fishing worldwide appears to be increasing as fishermen seek to avoid stricter rules in many places in response to shrinking catches and declining fish stocks. Few, if any, developing countries and only a limited number of developed ones are on track to put into effect by this year the International Plan of Action to Prevent, Deter and Eliminate Unreported and Unregulated Fishing. Despite that fact that each region has its Regional Sea Conventions, and some 108 governments and the European Commission have adopted the UNEP Global Programme of Action for the Protection of the Marine Environment from Land based Activities, oceans are cleared at twice the rate of forests. The Johannesburg forum stressed the importance of restoring depleted fisheries and acknowledged that sustainable fishing requires partnerships by and between governments, fishermen, communities and industry. It urged countries to ratify the Convention on the Law of the Sea and other instruments that promote maritime safety and protect the environment from marine pollution and environmental damage by ships. Only a multilateral approach can counterbalance the rate of depletion of the world’s fisheries which has increased more than four times in the past 40 years. 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