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 Posted: Tue Aug 28, 2007 10:04 am
Hey guys, I was reading threw my E.S. book and it’s just really depressing seriously.
I wanted to share with you some of the key points I thought were worth sharing with you, actually the whole book in my opinion is worth sharing but that would go on and on. I want to share my chapter outline along with some of my commentaries and questions that I propose to you or whoever cares.
1. Core Case Study: The Passenger Pigeon: Gone Forever
2. Species Extinction
3. Importance of Wild Species
4. Habitat Loss, Degradation and Fragmentation
5. Invasive Species
6. Population Growth, Pollution, and Climate Change
7. Overexploitation
8. Protecting Wild Species: Legal and Economic Approaches
The Sanctuary Approach
9. Reconciliation Ecology
I'd really appreciate it if out of this thread, you at least read the Core Case study.
All facts and information is retreived from my E.S. Textbook 'Living in the enviroment' 15th edition G.Tyler Miller JR.
Other sources will be sighted when used or used as references.
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Posted: Tue Aug 28, 2007 10:11 am
Core Case Study: The Passenger Pigeon: Gone Forever!!In 1813 there was huge flocks of passenger pigeons that took literally day’s to pass by and the flocks were so dence that it darkened the skies.
NO Lies:
By 1900, North America’s Passenger Pigeon, once the most numerous birds on earth, had disappeared from the wild because of a combination of uncontrolled commercial hunting and habitat loss as forests were cleared to make room for farms and cities.
These birds were good to eat, their feathers made good pillows, and their bones were widely used for fertilizer. They were easy to kill because they flew in gigantic flocks and nested in long, narrow, densely packed colonies. Commercial hunters took advantage of this setting traps and killing more than 1,000 birds at once. crying
One way they trapped these birds was by capturing one pigeon alive, sewing it’s eye’s shut, and tying it to a perch (called a stool). Soon a curious flock would land beside the “Stool Pigeon” then the birds would be shot or ensnared by nets that killed thousands at a time. In 1858, passenger pigeon hunting became a big business. The way these birds were killed is insane slaughter. Their roosts were they nested were burned below with sulfur to suffocate the birds. There is record of one professional pigeon trapper in 1878 who made 60,000 $$ by killing 3 Million Birds. How can we put a price on nature and a cheap price at that.
By the Early 1880’s only a few thousand birds remained, at that point recovery of the species was doomed because the females only laid one egg per nest each year. It is recorded that on March 24th 1900 a young boy in the US state of Ohio shot the last known wild Passenger pigeon.
Eventually all species become extinct or evolve into new species. The Archeological record reveals FIVE mass extinctions since life on earth began – each a massive impoverishment of life on earth. There is considerable evidence that we are now in the early stage of a sixth great extinction and that we are causing this as human population grows, consumes more resources, and disturbs more of the earth’s land and aquatic systems. If we keep impoverishing the earth’s biodiversity, eventually we will also be impoverished and there would be no place for us to escape.Aldo Leopold The last word in ignorance is the person who say’s of an animal or plant: “What good is it?”… If the land mechanism as a whole is good, then every part of it is good, weather we understand it or not… Harmony with land is like harmony with a friend; you cannot cherish his right hand and chop off his left.
This isn't the first case nor the only case of such a loss of natures beauty and resources, but if this doesn't pull at your heart. I don't know what will.
I can't agree more with Aldo Leopold.
A disturbing message from the birds:
Human activities are causing serious declines in the populations of many bird species.
Approximately 70% of the world’s 9,775 known bird species are declining in numbers and roughly one of every eight bird species is threatened with extinction. The majority of the world’s bird species are found in South America and about three-fourths of the threatened birds live in forests which we loose about a Greece size forest area each year. At least 23 species of seabirds face extinction and 40% of the world’s waterbirds.
Millions of migrating birds are killed each year when they collide with powerlines, communication towers, and skyscrapers that we have erected in the middle of their migration routes. While US hunters kill about 121 Million Birds a year, as many as 1billion birds a year in the US die when they fly into glass windows. Other threats to birds are Oil spills, exposure to pesticides, herbacides that destry their habitats and swallowing toxic lead shotgun pellets falling into wetlands and lead sinkers left by anglers.
The greatest new threat to birds is climate change.
Birds are an important factors in helping control populations of rodents and insects (which decimate many tree species), they clean up dead animal carcasses by eating them, they pollinate flowers, and spread plants throughout their habitats by consuming and excreting plant seeds.
question So why are birds important:
idea Well they play a key and specialized role in pollination and seed dispersal, especially in tropical areas..if they were to go extinct it may lead to the extinction of plants dependedt on the ecological services of the birds. Then some animals that feed on these plants may become extinct. Everything is connected.
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Posted: Tue Aug 28, 2007 10:15 am
Species Extinction:
Species can become Extinct in three ways: locally, ecologically, or globally.
To break it down quickly local extinction is when a certain species is not found in an area it once inhabited, ecological extinction is when a there are so few members of a species it can no longer play it’s ecological role in it’s community.
Side: An Ecological role is the total way of life (niche) of a species in an ecosystem.
An Ecosystem is a community of different species interacting with one another.
In easier words every species, be large or microscopic has a “job” in the community it lives in, when there is so little of a certain species left that it can no longer perform it’s job, then it is ecologically extinct. There is so much more to Ecosystems and roles of species, if there is something you would like to know that you don’t understand please feel free to ask me. Simply put when we talk about communities and niches think of the Circle of life- everything is connected.
Global extinction (biological extinction) is when a species is no longer found anywhere on the earth.
Species heading towards biological extinction are either Endangered or Threatened.
arrow What’s the difference?
idea Well a threatened species is likely to become extinct or endangered, to where an endangered species could soon become extinct.
A study in 2000 found that human activities threaten several types of species with premature extinction. Another survey found that one-third of the 21,000 plant and animal species in the United States are vulnerable to premature extinction. Does this bother anyone else or is it just me?
The 2005 Red List contains more than 16,000 species at risk of extinction. This includes one of every four mammal species, one of every seven plant species, and one of every eight bird species.
You can examine the Red List yourself Here
Examining extinction rates is not an easy job, primarily because typically it takes such a long time that it is not easy to document, secondly we have only identified 1.4Mil of the 4-100Mill species we are likely to have, lastly Scientist and especially the general public know very little about the species we have identified.
Scientist have observed that on average a 90% loss of habitat will cause the extinction of about 50% of the species living in that habitat. Researchers know that their estimates and model rates are inadequate and continue to strive for better data, But arguing over the numbers and waiting to get better data and models should not be used as an excuse for inaction.
Scientist estimate that the current rate of extinction is 100 to 10,000 times the rate before humans arrived on earth. Before human’s, calculations show that extinction rate was about 0.0001% per year…Let’s just say that our current rate of extinction is 100 times that which will amount to about 0.01% species extinction per year.
question How many species is that?!
arrow Well say we have 5million species on the plant; 5,000 will go extinct each year.
If we have 100Million, 100,000 will go extinct each year!
IS This crazy or what?!
Say we have 100Mil Species, at a 0.01x;tinction rate in less than 10yrs we will have lost 1Million Species. eek
idea Think about this: How might your lifestyle change if our activities cause the premature extinction of up to half of the world’s species in YOUR lifetime?
What are some things in your lifestyle that contribute to this threat?!
We can all list something.
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Posted: Tue Aug 28, 2007 10:16 am
Importance of Wild Species:
Why should we preserve wild species?
question So what is all the fuss about? If all species eventually become extinct, why should we care about loosing a few more?
New Species eventually evolve to take the place of those lost. So why should we care if we speed up the extinction rate over the next 50 – 100 yrs?
idea The answer is because it will take at least 5Mil years for natural speciation to rebuild the biodiversity we are likely to destroy during this century.
We should act now to prevent the premature extinction of species because of their instrumental value, their usefulness which a lot of people fail to understand. It’s quite simple really. We are all connected, if one species goes extinct another that depended on that species will follow, or be dangerously harmed by the extinction of one species.
Many species provide economic value in the form of food, crops, fuel wood, lumber, paper and medicine.
62% of all cancer drugs were created by bioprospecting discoveries, including the key ingredient in Taxol, which is used to treat breast cancer.
Here is a green Career for you: Bioprospecting which is the search for new chemicals in living things that will have some medical or commercial use.
Another instrumental value is the genetic information in species that allows them to adapt to changing envioromental conditions and to form new species. Carelessly eliminating many of the species making up the world’s vast genetic library is like burning books before we read them.
Wild species also provide a way for us to learn how nature works and sustains itself. In addition there is always the recreational pleasure of having wild plants and animals.
Wildlife tourism (ecotourism) generates at least $500 Billion per year worldwide.
It is estimated that one male lion to age 7 generates $515,000 in tourist dollars in Kenya but only $1,000 if it is killed for it’s skin. The up side of ecotourism is that it can inject money into local economies and allows visitors to learn about the natural world and perhaps appreciate it’s value and fragility.
The down side is that large numbers of people can not visit an ecosystem without disturbing it.
Another green Career: is Ecotourism Guide.
Biophilia (Ethics)
question So do we have an ethical obligation to protect species from premature extinction?
Some people believe that each species has an inherent right to exist.
Biophilia is having an inherent genetic kinship with the natural world.
question Do you have an affinity for wildlife and wild ecosystems?
If so how so you display this love of wildlife in your daily actions?
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Posted: Tue Aug 28, 2007 10:17 am
Habitat Loss, Degradation and Fragmentation
The greatest thread to a species is the distruction of the place where it lives.
Conservation Biologist have summarized the most important causes of Premature extinction using this acronym: HIPPO
H – habitat destruction
I – Invasive species
P – Population growth
P – Pollution
O – Over harvesting
(Will add more to this later)
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Posted: Tue Aug 28, 2007 10:18 am
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Posted: Mon Sep 24, 2007 12:04 pm
idea
Not done posting info, but feel free to post oppinions so far.
-Catz
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