lecture 18 Flashcards
Conservation biology
Life on Earth has experienced repeated
mass extinctions (5 periods of mass extinctions)
* The current Holocene extinction, aka the
biodiversity crisis, is different (mass extinction happening rn)
* Damage to Earth’s biodiversity results
from the actions of a single species: humans
History of conservation in Canada
- We created the second-biggest national park
Banff National Park was created in 1885; the first wildlife park in Canada and the third in the world - Ontario’s Algonquin Park was created in 1893
- Commission of Conservation was created
by Wilfrid Laurier in 1909 (with the idea that we should be trying to conserve organisms) - Migratory Birds Convention Act was passed in 1917 ( intergovernmental conservation)
- Canada has been a key player in setting aside land and creating policies to protect it
Cosewic
Today, the Committee on the Status of Endangered
- tries to find out if species are in decline or stable
- Create a review on what organisms might be in trouble
Wildlife in Canada (COSEWIC) studies
biodiversity loss
* Through 10 specialist committees that deal
with different taxonomic groups, COSEWIC
evaluate organisms of conservation concern
* COSEWIC uses six designations…
1. extinct
2. Endangered
3. extirpated
4. threatened
5. Special concern & data deficient
Extinct
A species that once occurred in Canada
but is no longer found anywhere on Earth
- 25 species, that once occurred in Canada and are now extinct, including:
- Labrador Duck
- Passenger Pigeon
- Great Auk
- Sea mink
- Deepwater cisco
- Macoun’s shining moss
- Striped bass
Extirpated
Extirpated: formerly occurred in Canada, but now survives only elsewhere
- 22 species, extirpated, including:
- Atlantic walrus
- Greater prairie chicken
- Timber rattlesnake
- Karner blue
- Dwarf wedge-mussel
- Oregon lupine
Endangered
Endangered: species that is at imminent risk of
extinction or extirpation in its Canadian range.
- There are 374 species endangered in Canada:
- Shortfin mako shark
- Vancouver Island Marmot
- Pacific Right whale
- Whooping crane
- Yucca moth
- Prickly pear cactus
- American chestnut
American Chestnut:
Endangered
Threatened
Threatened: species likely to become endangered
unless factors affecting risk are mitigated
* (164) 190 species:
* Swift fox
* Wood turtle
* Chimney Swift
* Gray ratsnake
* Northern fur seal
* Least bittern
Special concern & data deficient
Special concern: at risk
of becoming threatened
due to low numbers:
(192) 235 species
* Data deficient: available
information is not
sufficient to resolve
assessment: 59 species
* (172) 198 species have
been designated as “not
being at risk
Slender-billed curlew
- Extinct Nov 182024
overharvested and habitat reduction
Threatened
Threatened: species likely to become endangered unless factors affecting risk are mitigated
- On our radar it will be ok only if we act
Still around
* 200 species that are threatened here in canada:
* Swift fox
* Wood turtle
* Chimney Swift
* Gray ratsnake
* Northern fur seal
* Least bittern
Special concern & data deficient
Special concern: at risk
of becoming threatened
due to low numbers:
259 species (dont need to know #)
- We think it could become threatened
- Data deficient: available information is not
sufficient to resolve assessment: 61 species
*200 times where they have met and said there is no concern
Recovery strategies
All species listed by COSEWIC as endangered
or threatened must have a recovery strategy
* This strategy must focus on plans that will
increase the animal’s population to a viable
level
- If we do these things, we can get them off the endangered list
ex.
“The long-term recovery
goal: By 2026, restore a
self-sustaining swift fox
population of 1,000 or
more mature,
reproducing foxes that
does not experience
greater than a 30%
population reduction in
any 10-year period.”
Conservation biology concepts
All species listed by COSEWIC as endangered
or threatened must have a recovery strategy
* This strategy must focus on plans that will
increase the animal’s population to a viable
level
Minimum Viable Population
- Minimum viable population is the least abundance that would allow a population to persist in the wild.
ex. Florida panther - Minimal viable population size changes with location
- Calculated using computer simulation models
Success of these models rests on life history data including fecundity, mortality, longevity, and population ecology data such as immigration, inbreeding
*Feed data collected by field biologist into models
Keystone species
Keystone species have disproportionately large influence on ecological structure and functionality of their community
ex. starfish change whether kelp forest or sea urchin rich environment grows
ex. beavers: change environment structure
* Especially important for conservation biology, because if a keystone species is lost, an entire community will change
Umbrella species
Umbrella species are wide-ranging organisms that have a large home range and are components of many types of communities.
- Either travel a lot or live in lots of places.
- Conservation actions that affect them can
provide additional benefits for biodiversity - Examples: polar bear,
grizzly bear, timber wolf,
checkerspot butterfly
Conservation actions that effect an umbrella species effect a verity of habitats
Flagship species
- Flagship species are charismatic species that are used to profile the importance of conservation activities to the public
- Species that capture our attention and gets people behind conservation activity
- inspires people to think about environments they wouldn’t normally care about
- Conservation actions that affect them can
provide additional benefits for biodiversity - Examples: panda, polar
bear (makes people care about sea ice edge), timber wolf, orca, sugar maple (flagship for protecting forests in Canada)
Theory of island biogeography
*MacArthur and Wilson proposed
this theory to explain variation in
species richness on oceanic islands
- Over long time periods, an equilibrium condition is established between immigration and emigration (extinction)
- Optimal population size is in a balance between the two forces.
- Immigration curve and extinction curve that gives rise to population size
- Distant islands have lower immigration rate
of new species than near islands - Small islands support smaller populations, which have higher extinction rates than large islands.
- small island= high extinction rate
- big island= less high extinction rate
- close island, more immigration
- far island =less
ex. Small island near mainland: higher levels of species richness
ex. Higher species richness for big nearshore populations
Balance emigration and extinction
Prioritize smaller more distant islands because they are more likely to form extinction threats
Where to conserve
- Actions to sustain biodiversity must be
undertaken in two ways
1. Conserve biodiversity in areas that are used to provide the economy with natural resources - Areas that provide goods for humans-how do we maximize biodiversity here?
2. Preserve biodiversity in protected areas set
aside from intensive economical use - Conserve biodiversity in working areas is important
ex. shade coffee-avoid monoculture maintain some original vegetation
Protected areas
- How can we set aside protected areas that will maximize biodiversity
- These must be self organizing and protected ecosystems
- Often economically important-tourism
- Sometimes areas used for hunting
- Used for educational value
How to design protected areas? sloss
- Maximize the # of protected areas and the size of protected areas
- Ultimately, there is a trade-off between # of protected spaces and size
- Sloss should you invest in a single large or several small conservation areas.
Key factors: - Area:
- edge effects
- Number of protected areas
- Distance between protected areas
Large protected areas are associated with lower extinction probabilities than smaller areas
Numerous protected areas provide redundancy against catastrophic losses of endangered species
- depends on species
- shape (maximize interior habitat), spacing (gene flow and recolonization is more likly when closer together) and corridors effect (facilitate gene flow)
Increase protected areas
tot # of protected areas is increasing
tot area protected is increasing
aim to protect biodiversity hotspots
conservation management
Within protected areas:
* Prevent poaching and
harvest
* Prevent unauthorized
vehicle use
* Replace missing natural
factors, such as fire or
large animals
* Manage
reintroductions
education
Protected areas are important for providing
education and for experiencing nature and
wilderness. This results in positive attitudes
towards conservation of biodiversity.
Conservation success
Biodiversity reports are often depressing
* In the long term, bad news doesn’t motivate
to act
* Communication of good news is encouraging
* Example: Blue Lists (organisms that were taken off red list) to quantify the successes
(as opposed to Red Lists of threatened species)
American bison
WE overharvested until there were only a few hundred individuals
- Now their number is stable at about 100 000 bison
- WE kept them from becoming exstinct
grey seal
Over hunted until there were just a few thousand left
put quotas on how many you can hunt
pop at 450 000
Grey whales
several thousands left
- minimized overharvest now we have 26 000
Wild turkeys
Were exstripated from canada
- brought back for hunting
American ginseng
American ginseng (Panax
quinquefolius) an understory
species in hardwood forests
* Rhizomes are thought to have
medicinal properties
* Wild populations were
depleted for trade with China
* Listed as endangered by
COSEWIC, it is being
reintroduced across Canada
