species at-risk chapter 1.2 chapter 1.3. what’s out there? "scientists were startled in 1980...

SPECIES AT-RISK

Chapter 1.2

Chapter 1.3

What’s Out There?

"Scientists were startled in 1980 by the discovery of a tremendous diversity of insects in tropical forests. In one study of just 19 trees in Panama, 80% of the 1,200 beetle species discovered were previously unknown to science... Surprisingly, scientists have a better understanding of how many stars there are in the galaxy than how many species there are on Earth."

SPECIES AT RISK

Species whose populations decline below a certain level are considered to be at risk.

In Canada, there are 585 species in various degrees of risk as of April 2009, according to COSEWIC (Committee of the Status of Endangered Wildlife in Canada).

Summary table of Wildlife species assessed by COSEWIC

http://www.cosewic.gc.ca/eng/sct0/index_e.cfm#sar

Why are Species at Risk?

The reasons for an ecosystem decline, are the same reasons why certain species are put at risk.

1. Loss of habitat 2. Pollution 3. Diseases 4. Climate change / global warming 5. Accidental introduction of new species 6. Over harvesting certain species(hunting) 7. Competition 8. Increased use of pesticides and fertilizers 9. Natural environmental change / Mass Extinction

Classification system for At-Risk Species

1. EXTINCT – A species that is not found anywhere

EXAMPLES:o Blue Walleye (Type of Fish-1965 )o Passenger Pigeon ( 1914 ) link

Extinct Species

Passenger Pigeon

Blue Walleye

2. ENDANGERED

A species that is close to extinction in all parts of Canada or in a significantly large location.

EXAMPLES:o Eastern Cougar ( very rare sightings)o Beluga Whale ( St. Lawrence River )o Tigers (Not in Canada – link)o Atlantic Salmon ( very shortly )

Endangered Species

Beluga Whale

Endangered Species cont.

Eastern Cougar

Gorilla

Atlantic Salmon

3. EXTIRPATED

Any species that no longer exists in one part of Canada, but can be found in others

EXAMPLES:o Grizzly Bear (no longer in Man. and Sask.

but found in Alberta and BC)

Grizzly Bear

4. THREATENED

Any species that is likely to become endangered if factors that make it vulnerable are not reversed.

EXAMPLES: Wood Bison (small number) Anatum Peregrine Falcon (captive breeding

is helping to restore population)

Threatened

Peregrine Falcon Wood Bison

5. VULNERABLE or Special Concern

Any species that is at risk because of low or declining numbers at the fringe of its range or in some restricted area.

EXAMPLES:o Grey Foxo Atlantic Codo Blue Herono White tail Deer

Vulnerable/Special Concern

Grey Fox Blue Heron

Atlantic Cod White-

Tailed Deer

Which at-risk category is the most devastating? Answer: Extinction

The rapid loss of species we are seeing today is estimated by experts to be between 1,000 and 10,000 times higher than the natural extinction rate.

• These experts calculate that between 0.01 and 0.1% of all species will become extinct each year.

• If the low estimate of the number of species out there is true - i.e. that there are around 2 million different species on our planet -  then that means between 200 and 2,000 extinctions occur every year.

• But if the upper estimate of species numbers is true - that there are 100 million different species co-existing with us on our planet - then between 10,000 and 100,000 species are becoming extinct each year.

In the modern world, extinction rates of species on planet Earth are increasing at an alarming rate.

Between the years1600 and1900 the estimate is that one species went extinct every four years.

It was projected that we lose one species every 30 minutes, that is about 17,500 per year… Gone forever!

Species extinction rates are increasing dramatically as the human population grows.

Species at risk of extinction is growing, at the rate of about 80 species per year.

Some species learn to adapt to major changes in their ecosystems, others die.

In either case, this has major effects on each ecosystem and food chain.

Biological diversity is the resource upon which families, communities, nations and future generations depend. It is the link between all organisms on earth, binding each into an interdependent ecosystem, in which all species have their role. It is the web of life.

EFFECTS OF EXTINCTION

The number and variety of species in an ecosystem is described as the biological diversity or BIODIVERSITY of the ecosystem.

The reduction in biodiversity caused by the extinction of a single species can cause a “domino effect” with many negative effects.

When the threatened species acts as a predator, it keeps the population of its prey in check.

EFFECTS OF EXTINCTION

When it acts as prey, it provides an important food source.

So, An increase in Biodiversity = Healthy ecosystem.

A decrease in Biodiversity = greater chance of Ecosystem Collapse.

SEA OTTER EXAMPLE

Decrease in the Sea Otter (predator) Means an increase in Sea Urchins Means a decrease in Kelp (form of seaweed) Means a decrease in Fish (relies on seaweed

for habitat and food) By protecting the Sea Otters it caused an

increase in fish which balanced out the food chain and therefore the ecosystem.

PLEASE ANSWER QUESTION # 2 PAGE 15 OF TEXT

ANSWERS TO QUESTION #2

A) Threatened B) Endangered C) Extirpated

Endangered Species in Canada

Booklet and Worksheet