Introduced Species: The Threat to Biodiversity & What Can Be Done
By: Daniel Simberloff
An article from ActionBioscience.org
Copyright 2000
http://www.actionbioscience.org/biodiversity/simberloff.html
Summary
Introduced species are a very big threat to the environment because they can cause many changes, like: overcrowding an area and replacing a native species, costing the economy tons of money by damaging human enterprise, and even placing entire ecosystems at risk by changing the habitat. It has been proven that introduced species are the cause of 49% of species becoming endangered. In addition, the combination of harvest, pollution, and disease isn’t even as much of a threat to biodiversity as introduced species are. Also, the U.S. economy loses 137 billion dollars a year to repair damages introduced species cause.
When a new species is introduced to another environment, there is a lot of competition that goes on between the native and introduced species for things like food and water. An example of this was when the predatory brown tree snake was introduced to Guam from the Admiralty Islands. The human impact on this scenario is the plain fact that they were the ones who brought the snake over (by cargo). This new species has had a major impact on Guam. Ten of eleven native bird species there were wiped out because of the brown tree snake. Another example of the impact of introduced species is when the greedy Nile perch was introduced to Lake Victoria. Since it was first brought over, the Nile perch has eliminated more than one hundred species of cichlid fish native to the area. Finally, red squirrels in Great Britain have almost gone extinct because of the competition between them and the North American gray squirrels for food. The North American gray squirrels are more efficient at searching for nuts, and as a result, they are eating most of the red squirrels’ food before the red squirrels even have a chance to find it.
Often, it is the introduced species who change an entire habitat that are causing the greatest impact. When these species alter a specific place, lots of native species that can thrive only in the particular area become extinct. Species like fungi, trees, and aquatic plants have all proven just how powerful they can be. Other times, invaders can endanger a single species or a group of species without adjusting the environment in any way whatsoever. The brown tree snake and the Nile perch mentioned above are good examples of this. Finally, invasive species do their work sneakily, but it still can cause destruction. When invasive species use a process called hybridization, or cross-breeding, to eliminate a native species, this is an example of their subtle efforts. By breeding with the native species, the invasive species alters the native species’ gene pool, so that the native species develop into a form of the invasive species.
There are three main pathways that aid in the fastest spread of invasive species: wooden packing material, ballast water, and gardening plants. However, invasive species that are discovered early on can be destroyed. Currently, there are several technologies that can greatly help to control invasive species: biological, chemical, and mechanical. When an enemy from the same place as the unwanted pest is introduced to control the invasive species, it is called biological control. Using a pesticide like insecticide or herbicide is an example of chemical control. Finally, when hand pulling or different types of machines are used, it is considered mechanical control. There is a new technology being developed, called ecosystem management, that gives an entire ecosystem a ‘treatment’ (like a simulated fire) regularly. These ‘treatments’ often favor the survival of the native species over the introduced species. While not all these methods are 100% effective, they can help greatly in controlling unwanted pests.
The best solution for addressing the invasive species issue is through international cooperation and management. When the Rio Convention of Biological Diversity acknowledged the situation as a threat and pressed a need for action, there was a great international response. Now, a Global Invasive Species Program formed by international organizations (like the United Nations) is helping out by developing programs to deal with introduced species. It is great that people are finally trying to help out with this serious issue because if no one took action, then the invasive species would most definitely take over.
As you can see, introduced species often have a negative impact on the new place they’re introduced to, and this is the reason why measures need to be taken to prevent this from happening over and over again.
Opinion/Reflection
I can’t believe how much of an impact introduced species can have to a particular environment. Before reading this article I was never aware of just how powerful these species can be, and how humans have no definite way of stopping them. However, it is often the human impact that causes these issues in the first place, by introducing a new species to an area because they believe it will provide some sort of benefit. I find it sad how different species often have to suffer because of human mistakes. Competition goes on between the native species and the introduced species, which is understandable, because the introduced species has different adaptations and body structure than the native species. For instance, in the bird experiment we did in class, the introduced species was adapted to eat all the different kinds of food, whereas the native species could only eat a particular type of food that they could pick up with their beak. Invasive species often win the competition, and the native species begins to die out. Reading this article, I also thought it was clever what the introduced species will do to take over an environment, even if they aren’t introduced by humans. For example, invasive species will use hybridization to get the native species to evolve into something much like themselves. I found this extremely smart.
Ask Questions
1) Do you think humans will be able to stop the spread of invasive species, or at least control it?
2) What are other examples of an invasive species taking over an environment?
3) Do you believe it is ever possible for an environment to benefit from an invasive species?
4) What is your take on how international management will occur? Do you think it will truly be helpful, or will it be done so that particular organizations can look good in front of the public?
5) Of the controlling methods mentioned in the article, which do you think would be the most effective to use on an invasive species? Why?
Wednesday, February 16, 2011
Monday, February 14, 2011
EPA to Get Short End of the Stick from the Feds?
THE RED SIDE...
According to the New York Times, congressional Republicans are pushing to cut $3 billion from the EPA's FY (Fiscal Year) 2012 budget in the hopes to reduce the nation's $1 trillion debt. These cuts would constitute 69% of the total cuts in spending the Republicans are proposing, which also includes cutting the Dept. of Energy's Efficiency and Renewables Program by over one-third of its FY 2011 budget. The Republicans also want to lay off 20,000 research positions at the National Science Foundation and want to prevent the EPA from creating and enforcing greenhouse gas emissions rules.
Relatively more minor goals for the GOP are to remove competitive grants for local land-use planning, eliminate the White House Energy and Climate Advisor's Office, and to change the definition of the term "navigable waters" in the Clean Water Act.
In response to claims from the Democrats that they are willing to risk a government shutdown in order to cut spending as much as possible, the Republican House Majority Leader, Eric Cantor, accused the Democrats of fear-mongering.
...THE BLUE SIDE...
The Democrats, on the other hand, the White House in particular, want to freeze all non-military discretionary (optional) spending for five-years and give the DOE $8 million to spend on researching clean energy technology. Obama's budget also contains other big investments, but those do carry a level of risk. Democrats also, as mentioned earlier, accuse the Republicans of risking a government shutdown to cut spending as much as possible. Sen. Chuck Schumer of New York said, "We're willing to meet Republicans in the middle on spending, but they keep lurching to the right. This is what happens when you pick a number first and figure out the cuts later," saying that the Republicans are making a poor choice in deciding how much to cut before deciding what programs to cut.
...MY SIDE...
I think the Democrats have some good ideas. Stuff like the EPA and the DOE are important, and like Schumer said, you can't just pick numbers and then cuts. We have to see what we should and should not cut before we create a final number.
...AND YOUR SIDE
1) Which side do you pick? The Republicans, who support drastic short-term cuts but include cuts to the EPA? Or the Democrats, who have a long-term plan but include large, potentially risky investments?
2) In any situation, do you think ANY cut to the EPA is a good idea?
3) What do you think are the pros and cons of each party's plan?
4) What would you propose if you were a member of Congress?
Thursday, February 10, 2011
Step right up and take your bets! Climate Science vs. Climate Economics!
This is based off an article from Grist.org written by David Roberts.
So as some of you may not know, and I didn't until I read this article, there are two new stories coming out about climate change. No this is not the old debate about whether or not climate change is really happening between scientists and politicians, but rather the two different visions about what we can expect in the future. They don't fit very well though so let's do what we do to all things that don't match up together... pit them against each other and see who wins! So without further ado lets get on with the show!
IN THIS CORNER: SCIENCE!
Now in the corner of science we have something that I am sure no one wants to see... the calm collected group of geniuses we call scientists more and more panicked with every new story that comes in. With this new information it is being predicted that there is a real (if extremely difficult to quantify ) risk of civilization-threatening scenarios kind of like a bad SyFy original movie. The standard line among "climate hawks" (which I am assuming is a term for people who harp constantly about what we need to do to save the enviroment) is that science recommends that developed world countries an "80% reduction of greenhouse gases by 2050"; globally the goal is 50% by 2050. But even that high amount could be severly underestimated as it is based off the last IPCC which is by all accounts is "woefully conservative" especially when compared to the uniform grim nature of the science since that report came out. For the U.S. to get back to the ambitious target of 350 ppm (parts-per-million) of carbon in the atmosphere the U.S. would have to build the following EVERY YEAR until 2050 according to the IEA (Internationial Enviromental Agency):"... 35 coal-fired and 20 gas-fired power plants with carbon capture and storage; 30 nuclear power plants; 12,000 on shore wind turbines paired with 3,600 offshore ones; 45 geothermal plants; 325 million square meters-worth of photovoltaics; and 55 solar-thermal power plants. That doesn't even include the need to build electric cars and hydrogen fuel cell vehicles in order to shift transportation away from burning gasoline." ...wow that is alot and that would cost the U.S. a very pretty penny. Probably a 1843 double headed lincoln penny made out of gold and uranium to be precise. Yeah according to the article that would be the equialent of "America's massive industrial build-up for WWII only across the entire globe for 40 years straight (at least) against a faceless enemy." So yeah my brain hurts from trying to cacluate the cost of that, how about yours. So...should we do it? Is such a massive shift "worth it"? Heh...funny you should ask.
IN THIS CORNER: ECONOMICS!
Economists are the arbiters of "worth it" these days, so how do they figure it out? Well the short answer is that they build charts and models that are informed thought various assumptions about the range of damages expected from climate change, the range of costs expected from avoiding climate change, and the rate of economic growth. The general idea is to find the the perfect balance between spending on adaption and the cost of potential damages so we don't overpay to fix it and we don't underpay to fix it. The analogy the writer uses is probably the best I can think of; he says that economists are "...like Goldilocks, economists seek a course of action that's just right: the most economically efficent course. For this discussion the fact of the matter is that virtually every model that shows human growth depending on what the climate does all have two things in common. One; they show human beings getting richer over the next century regardless of what the climate does. The range of scenarios goes from much-richer-very-quickly to... somewhat-less-richer-more-slowly, depending on what numbers or assumptions are plugged in. Two; None of them show human progress just hitting a plateau (with no drop at all, no matter how miniscule) much less falling of some kind of a cliff. According to the article, a well-known british economist named Frank Ackerman has noted that even with what is classified as the extreme worst case scenario (a 35 percent reduction in income below baseline) the world would only be about eight times richer by 2200. So, according to economists, the worst thing policymakers risk by doing nothing to fix climate change is somewhat slower economic growth. So one way or another, we're getting richer. This is a perfect example of what the foundational faith of modern economics is. It is a faith in human adaptability and ingenuity. What that basiclly means is that every chart is based on the belief that humans can master ANY circumstance over time. Because of this you will never find a model with a Jared Diamond- or James Lovelock-style apocalypse. Instead our future generations will be much wealthier and thus be better able to cope with the problem.
So how do we put these two stories together? Is climate change truly an existential threat -- an immediate dnage and a small but growing risk of total or near total collapse of society? Or is it creeping change to which humans need to make a carefully thoughout and economically oprimised response as it continues to grow? How do we fit these two versions of the same story together in our head? And more importantly what, with these tow totally different visions, should we do?
AND THE WINNER IS...
Of course economists would tell you that they have already done the work of fitting these two visions together for you. That's what the models are meant to do. The damages of potential climate change are already built in and the results don't look like a catastrophe because, dammit, Man Will Overcome. Anyway that's what the models will tell you. But if you talk to the economists themselves, well, they are not quite as gung ho. Fpr one they themselves admit that the models are not very good at incorporating large short-term shocks. The "long-tail" possibilities in climate science -- the low-probability, high-impact stuff like iceshelves collapsing or thermohaline circulation shutting down -- completely borks the models. You start seeing wild sings in model projections based on those small adjustments and the models in essence start saying "hell if I know!" When economist run into these limitations of their models they tend to heed the Wittgensteinian injuction: Whereof one cannot speak, thereof one must be silent, which in laymans terms means "You don't know, so don't say anything!" They don't feel comfortable making policy recommendations without solid modeling to back it up. Giving counseling in the face of such gigantics and unquantifiable risk starts to feel less like a science and more like an excercise in politics or ethincs. Heaven forbid. Unfortunately that allows economists whose model tells a nice little story of slowly rising costs, smoothl offset bu a slowly rising carbon tax. The message: don't panic. That message is all too welcome in the halls of power where they are looking for any excuse to sit back and do nothing. The final statement is a rather good metaphor for what is happening. "We are stumbling around in the dark, in an area where scientists tell us some very, very nasty beasties dwell. In that situation, it sems to me the overwhelming bias should be toward action -- getting lean, mean, and nimble enough to handle ourselves no matter what slouches our way."
OPINION
For my part I agree with the author listen to the scientists information and not the economists chart. We are treading in some very dangerous water and if we don't do something now to at least slow down this increase, we will probably learn the hard way that the scientists were right, the economists were wrong, and we are not getting rich any time soon.
QUESTIONS
1) What side are you on? Economists or Scientists? Why?
2) What do you think the effects will be of climate change?
3) What would you do to try and at least slow down the climate change?
4) Do you think that man will overcome?
So as some of you may not know, and I didn't until I read this article, there are two new stories coming out about climate change. No this is not the old debate about whether or not climate change is really happening between scientists and politicians, but rather the two different visions about what we can expect in the future. They don't fit very well though so let's do what we do to all things that don't match up together... pit them against each other and see who wins! So without further ado lets get on with the show!
IN THIS CORNER: SCIENCE!
Now in the corner of science we have something that I am sure no one wants to see... the calm collected group of geniuses we call scientists more and more panicked with every new story that comes in. With this new information it is being predicted that there is a real (if extremely difficult to quantify ) risk of civilization-threatening scenarios kind of like a bad SyFy original movie. The standard line among "climate hawks" (which I am assuming is a term for people who harp constantly about what we need to do to save the enviroment) is that science recommends that developed world countries an "80% reduction of greenhouse gases by 2050"; globally the goal is 50% by 2050. But even that high amount could be severly underestimated as it is based off the last IPCC which is by all accounts is "woefully conservative" especially when compared to the uniform grim nature of the science since that report came out. For the U.S. to get back to the ambitious target of 350 ppm (parts-per-million) of carbon in the atmosphere the U.S. would have to build the following EVERY YEAR until 2050 according to the IEA (Internationial Enviromental Agency):"... 35 coal-fired and 20 gas-fired power plants with carbon capture and storage; 30 nuclear power plants; 12,000 on shore wind turbines paired with 3,600 offshore ones; 45 geothermal plants; 325 million square meters-worth of photovoltaics; and 55 solar-thermal power plants. That doesn't even include the need to build electric cars and hydrogen fuel cell vehicles in order to shift transportation away from burning gasoline." ...wow that is alot and that would cost the U.S. a very pretty penny. Probably a 1843 double headed lincoln penny made out of gold and uranium to be precise. Yeah according to the article that would be the equialent of "America's massive industrial build-up for WWII only across the entire globe for 40 years straight (at least) against a faceless enemy." So yeah my brain hurts from trying to cacluate the cost of that, how about yours. So...should we do it? Is such a massive shift "worth it"? Heh...funny you should ask.
IN THIS CORNER: ECONOMICS!
Economists are the arbiters of "worth it" these days, so how do they figure it out? Well the short answer is that they build charts and models that are informed thought various assumptions about the range of damages expected from climate change, the range of costs expected from avoiding climate change, and the rate of economic growth. The general idea is to find the the perfect balance between spending on adaption and the cost of potential damages so we don't overpay to fix it and we don't underpay to fix it. The analogy the writer uses is probably the best I can think of; he says that economists are "...like Goldilocks, economists seek a course of action that's just right: the most economically efficent course. For this discussion the fact of the matter is that virtually every model that shows human growth depending on what the climate does all have two things in common. One; they show human beings getting richer over the next century regardless of what the climate does. The range of scenarios goes from much-richer-very-quickly to... somewhat-less-richer-more-slowly, depending on what numbers or assumptions are plugged in. Two; None of them show human progress just hitting a plateau (with no drop at all, no matter how miniscule) much less falling of some kind of a cliff. According to the article, a well-known british economist named Frank Ackerman has noted that even with what is classified as the extreme worst case scenario (a 35 percent reduction in income below baseline) the world would only be about eight times richer by 2200. So, according to economists, the worst thing policymakers risk by doing nothing to fix climate change is somewhat slower economic growth. So one way or another, we're getting richer. This is a perfect example of what the foundational faith of modern economics is. It is a faith in human adaptability and ingenuity. What that basiclly means is that every chart is based on the belief that humans can master ANY circumstance over time. Because of this you will never find a model with a Jared Diamond- or James Lovelock-style apocalypse. Instead our future generations will be much wealthier and thus be better able to cope with the problem.
So how do we put these two stories together? Is climate change truly an existential threat -- an immediate dnage and a small but growing risk of total or near total collapse of society? Or is it creeping change to which humans need to make a carefully thoughout and economically oprimised response as it continues to grow? How do we fit these two versions of the same story together in our head? And more importantly what, with these tow totally different visions, should we do?
AND THE WINNER IS...
Of course economists would tell you that they have already done the work of fitting these two visions together for you. That's what the models are meant to do. The damages of potential climate change are already built in and the results don't look like a catastrophe because, dammit, Man Will Overcome. Anyway that's what the models will tell you. But if you talk to the economists themselves, well, they are not quite as gung ho. Fpr one they themselves admit that the models are not very good at incorporating large short-term shocks. The "long-tail" possibilities in climate science -- the low-probability, high-impact stuff like iceshelves collapsing or thermohaline circulation shutting down -- completely borks the models. You start seeing wild sings in model projections based on those small adjustments and the models in essence start saying "hell if I know!" When economist run into these limitations of their models they tend to heed the Wittgensteinian injuction: Whereof one cannot speak, thereof one must be silent, which in laymans terms means "You don't know, so don't say anything!" They don't feel comfortable making policy recommendations without solid modeling to back it up. Giving counseling in the face of such gigantics and unquantifiable risk starts to feel less like a science and more like an excercise in politics or ethincs. Heaven forbid. Unfortunately that allows economists whose model tells a nice little story of slowly rising costs, smoothl offset bu a slowly rising carbon tax. The message: don't panic. That message is all too welcome in the halls of power where they are looking for any excuse to sit back and do nothing. The final statement is a rather good metaphor for what is happening. "We are stumbling around in the dark, in an area where scientists tell us some very, very nasty beasties dwell. In that situation, it sems to me the overwhelming bias should be toward action -- getting lean, mean, and nimble enough to handle ourselves no matter what slouches our way."
OPINION
For my part I agree with the author listen to the scientists information and not the economists chart. We are treading in some very dangerous water and if we don't do something now to at least slow down this increase, we will probably learn the hard way that the scientists were right, the economists were wrong, and we are not getting rich any time soon.
QUESTIONS
1) What side are you on? Economists or Scientists? Why?
2) What do you think the effects will be of climate change?
3) What would you do to try and at least slow down the climate change?
4) Do you think that man will overcome?
Tuesday, February 8, 2011
Wolverines to Vanish From US Due to Warming?
Article
Summary:
Rising temperatures threaten to drive American wolverines to extinction. The wolverines have adapted to cold weather, to the point that there very survival as a species depends on it. Besides having numerous cold-weather adaptations, such as special fur to keep them warm and paws well-suited to snowy terrain, wolverines shelter their newborns in dens built from snow. Shifting climates could eliminate the spring time snow, causing a sharp drop in the reproduction rates of the wolverines, causing a sharp drop in their population. Some conservationists are talking about reintroducing wolverines into the wild to help keep the population up. Computer simulations report that if global warming continues at it's current pace, or even a more moderate one, American wolverines would have to rapidly adapt to very different conditions or face extinction.
Opinions:
Honestly, I didn't even know that wolverines lived in America, there are so few left. This really goes to show how our lazy attitude towards climate change is having serious consequences, and it's really just the beginning. How many other species could be facing similar fates due to climate change? And the extinction of the wolverine could cause ripple effects throughout it's community, causing populations of other organisms to chance, and possibly bring other species down with it. I think we really have to step up our game.
Questions:
1) Why aren't more steps being taken to prevent or reverse climate change?
2) Do you think the extinction of the wolverine would wreak havoc on its community?
3) What steps do you think we could take to help save the wolverine?
4) Do you think wolverines will disappear from the American wild?
Summary:
Rising temperatures threaten to drive American wolverines to extinction. The wolverines have adapted to cold weather, to the point that there very survival as a species depends on it. Besides having numerous cold-weather adaptations, such as special fur to keep them warm and paws well-suited to snowy terrain, wolverines shelter their newborns in dens built from snow. Shifting climates could eliminate the spring time snow, causing a sharp drop in the reproduction rates of the wolverines, causing a sharp drop in their population. Some conservationists are talking about reintroducing wolverines into the wild to help keep the population up. Computer simulations report that if global warming continues at it's current pace, or even a more moderate one, American wolverines would have to rapidly adapt to very different conditions or face extinction.
Opinions:
Honestly, I didn't even know that wolverines lived in America, there are so few left. This really goes to show how our lazy attitude towards climate change is having serious consequences, and it's really just the beginning. How many other species could be facing similar fates due to climate change? And the extinction of the wolverine could cause ripple effects throughout it's community, causing populations of other organisms to chance, and possibly bring other species down with it. I think we really have to step up our game.
Questions:
1) Why aren't more steps being taken to prevent or reverse climate change?
2) Do you think the extinction of the wolverine would wreak havoc on its community?
3) What steps do you think we could take to help save the wolverine?
4) Do you think wolverines will disappear from the American wild?
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