Farmland, settlements and highways have replaced much of Ontario's deciduous forest. Habitat loss and fragmentation are threats, with loss most extreme in conversion to farmland and urban development. This divides ecosystems and exposes more habitat to pollution. To protect sustainability, conservation aims to maintain large, connected areas with low external influences. Threats also impact aquatic ecosystems through activities like shoreline development, dredging, sedimentation and wetland drainage.

1. habitat loss & frag
mentation

2. Habitat Loss and FragmentationHabitat Loss and Fragmentation
A simple glance out
the window provides
evidence of habitat
loss…

3. Farmland, human settlements and
highways have replaced much of
southern Ontario’s once extensive
temperate deciduous forest ecosystem.

4. A view from the top of the CN Tower
reveals a human-dominated landscape.
Little of the original natural forest remains.

5. Habitat Loss and FragmentationHabitat Loss and Fragmentation
An extreme example of habitat
loss is the conversion of large
areas of natural ecosystems
into farmland and urban
development.

6. Habitat Loss and FragmentationHabitat Loss and Fragmentation

7. QuickTime™ and a
decompressor
are needed to see this picture.
In Canada, most of the habitat loss
occurred during the nineteenth and
early twentieth centuries when land
was cleared for farmland.
Toronto, 1876

8. More recently, natural habitat has been lost
to urban sprawl and transportation routes

9. Fragmentation of natural ecosystems
reduces their sustainability.
Fragmentation is the dividing up of a region
into smaller parcels or fragments.
Habitat Loss and FragmentationHabitat Loss and Fragmentation

10. When large ecosystems become fragmented,
species with large ranges may not have
enough area to survive.
Habitat Loss and FragmentationHabitat Loss and Fragmentation

11. In a fragmented ecosystem, more of the
habitat is exposed to damaging outside
influences such as pollution.

12. There are several key
factors that enhance
ecosystem sustainability,
which are considered
when deciding which
areas should be set aside
for protection and
conservation…
Habitat SustainabilityHabitat Sustainability

13. 1. Size
– Large blocks support larger and more stable
populations and communities
Habitat SustainabilityHabitat Sustainability
Poorer Option Better Option

14. 2. Number
– One large area is better than an equal area
composed of many smaller fragments
because there is less outside influence
Habitat SustainabilityHabitat Sustainability
Poorer Option Better Option

15. 3. Proximity
– The closer the ecosystem fragments are to
each other, the greater the chance
populations will be able to use the entire area
Habitat SustainabilityHabitat Sustainability
Poorer Option Better Option

16. 4. Connectedness
– Interconnected areas provide wildlife corridors
and permit migration between larger blocks
Habitat SustainabilityHabitat Sustainability
Poorer Option Better Option

17. 5. Integrity
– Access by roads and trails can increase
pollution, hunting and fishing
Habitat SustainabilityHabitat Sustainability
Poorer Option Better Option

18. On a global scale, habitat
loss and fragmentation are
second to climate change
as the most serious threat
to sustainability of natural
terrestrial ecosystems.
Habitat SustainabilityHabitat Sustainability

19. Habitat loss is most pronounced in Africa,
Latin America and the Caribbean.
Habitat SustainabilityHabitat Sustainability

20. Expanding human populations are placing
pressure on the land base to supply more
food and raw materials.

21. In the Amazon, which is the world’s largest
remaining rainforest, clearing and burning
are the greatest threats to the ecosystem’s
sustainability.

22. This is most often done to create pasture for
cattle sold to foreign markets

23. If we reduce the demand for agricultural
products produced in tropical regions, we
can reduce rainforest habitat loss.
Habitat SustainabilityHabitat Sustainability

24. Habitat SustainabilityHabitat Sustainability
Causes of Deforestation in the Amazon, 2000-2005

25. Habitat SustainabilityHabitat Sustainability
Ontario is no longer experiencing a rapid
loss of native ecosystems, but there is still
reason for concern.
The remaining threatened areas require
wise management.

26. Habitat SustainabilityHabitat Sustainability
The loggerhead shrike is
threatened by habitat loss.
The range of this small
predatory bird once covered
much of southern Ontario.

27. Habitat SustainabilityHabitat Sustainability
Over the past 50 years, changes in agricultural
practices have caused the loss of nesting
habitat for the shrike.

28. Habitat SustainabilityHabitat Sustainability
Once a common bird, the
population reached a low
of 17 breeding pairs in
Ontario in 1997.
The Loggerhead Recovery
Team has developed a
habitat conservation plan
to promote habitat
restoration

29. Wetlands & Aquatic EcosystemsWetlands & Aquatic Ecosystems
Human activities also
threaten aquatic
ecosystems.
In many cases, human
activities along shorelines
damage neighbouring
aquatic ecosystems

30. Wetlands & Aquatic EcosystemsWetlands & Aquatic Ecosystems
Human Activity: Replacing natural
vegetation along coastlines and
waterfronts
Impact:
– habitat destruction
– shoreline erosion
– loss of some species
– loss in breeding areas such as fish
spawning beds

31. Wetlands & Aquatic EcosystemsWetlands & Aquatic Ecosystems
Human Activity:
Dredging to create
deeper water for boats
Impact:
– disruption of bottom-
living organisms and
spawning beds
– habitat destruction

32. Wetlands & Aquatic EcosystemsWetlands & Aquatic Ecosystems
Human Activity: Sediment
runoff from land-clearing,
agricultural and forestry
operations
Impact:
– sediments may smother
natural habitats

33. Wetlands & Aquatic EcosystemsWetlands & Aquatic Ecosystems
Human Activity: Commercial Fishing
Impact:
– bottom trawlers and drag lines injure
and kill bottom-dwelling organisms
– damage to abiotic features

34. Wetlands & Aquatic EcosystemsWetlands & Aquatic Ecosystems
Human Activity: Draining wetlands for
urban expansion and agriculture
Impact:
– loss of wetland habitats
and associated species

35. Wetlands & Aquatic EcosystemsWetlands & Aquatic Ecosystems
Natural wetlands are flat and often
have deep, nutrient-rich soil with an
abundant water supply.
These conditions are ideal for
agriculture.

36. The result is that most large wetlands in
populated parts of Ontario have been
drained and converted to farmland.
The Holland Marsh

37. There is a push to reverse
this trend and re-establish
wetlands. Creating new
wetlands makes valuable
habitats for wildlife and
waterfowl.
Wetlands & Aquatic EcosystemsWetlands & Aquatic Ecosystems