Exam 3 Flashcards
Non-native organism that is introduced into an
ecosystem out of it’s native range and
establishes as part of the community and
competes for a particular niche
exotic species
A species becomes invasive when
they cause
ecological, environmental, or economic harm or when a
species is harmful to human health
Not all exotic species are
invasive - they must cause harm or significantly affect the native system to be considered invasive
Not all invasive species are
exotic, some native species can become invasive and cause harm to the ecosystem
through over population.
Problems Caused by Exotic Species
Take advantage of exploiting resources relative
to minimal constraints from limiting factors or
Outcompete native species for resources
Prevent access to resources for some species
Take advantage of lack of predators, natural
diseases/parasites that would otherwise control
their populations
Introduction of diseases and pests
purposefully brought into non-native
range
intentional introduction
non-intentional introductions
accidental introduction
examples of intentional introduction
Agriculture, live stock forage, horticultural ornamentals, biocontrol,
recreation, aesthetics
Deliberate attempt to surround a new area with familiar flora
and fauna
98% of the US crops and livestock are non-native and some
have become invasive
examples of accidental introduction
Jump dispersal via cargo transport, ballast water in ships,
accidental “hitch-hikers” with any sort of travel to non-native
ranges
Escape from transport or captivity, pets escaping into the wild
Numbers of non
natives birds
highest on
island nations:
New Zealand
and Puerto Rico
Accidental import of pathogenic fungus on ornamental
nursery cargo from Japan in early 1900’s
Wind dispersed, kills trees from the bark and cambium
chestnut blight
damages American elm
populations, vector and fungus are exotic
Introduced from Asia to Netherlands and then eventually
to US and dispersed by exotic elm bark beetle
Dutch Elm Disease
Japan, 1876 Erosion control, livestock feed Possible Biofuel ???
Kudzu
Introduced intentionally to prevent erosion along roadsides Crowds native aquatic and hydric species in wetlands Reduces water flow in wetlands and hydric environments Harms larval amphibians (mostly frogs) with plant tannins Managed with biocontrol – beetles (often exotic) released into it’s habitat and they eat the leaves of the plant eventually killing it
purple loosestrife
Native to southeast Asia Introduced as pets Hurricane disturbance and release/escape from breeding facilities in South Florida
burmese python
1890 introduced 48 birds from Shakespeare’s plays to Central Park, New York, nest thieves and impact on native breeding bird populations
starling
Introduced to Australia in 1930’s to control pests in the sugar industry Outcompetes native amphibians and devours native insects
cane toad
Humans as part of nature: the utilitarian view of wilderness
Pro: acknowledges the necessary human use of nature. Con: may result in the loss of the cultural, aesthetic, and functional roles wilderness plays.
Humans as separate from nature: the intrinsic view of wilderness
Pro: minimization of human impacts Con: limits the meaningful role humans may play in their
ecological surroundings. Con: led to the physical displacement of native peoples from
newly designated ‘nature’ reserves or to the erasure of their
historical influence on the landscape (green imperialism) Pro: the motivation for distinguishing humans from the rest
of nature also reflects the desire to determine what aspects
of the environment should be preserved in the face of
pervasive human impacts
resolving the tension, The acceptance of a paradox
humans are
separate from and part of nature
The tree in the garden argument:
A humanized wilderness does not have
the same connectedness of a “wild” and untouched wilderness
The pragmatic argument
The accelerating loss of species suggests we should discard our debates over the meaning of wilderness and instead focus on conservation and developing criteria to evaluate human impacts and prevent further degradation
The species-area argument:
Large, undeveloped, interconnected lands are essential for some species. Small developed tracts of land are unable to support the disturbance regimes, habitats, and resources for these species – thus we need large wilderness areas for protecting biodiversity.
The baseline argument:
Wild areas are models for ecological restoration and should be preserved in as rare a state as possible as reference conditions
The Wilderness Society Desire to create legal definition of “wilderness”
Took 8 years to write the document (almost 70 drafts!) Signed into law by President Lyndon B. Johnson, Sept 3, 1964
Signing of the Act, created the National Wilderness Preservation Society (NWPS) Originally all lands are protected by other federal designation 1st and then secondly as wilderness Managed by National Park Service, Fish and Wildlife Service, National Forest Service, and Bureau of Land Management
wilderness act of 1964
according to the wilderness act of 1964, human activities can include
Scientific study
Non-mechanized recreation
“Leave no trace” recreational activities
according to the wilderness act of 1964, human activities can not include
Mechanized vehicles or equipment (no cars, atv’s, chainsaws, etc…) Major ecosystem alterations, modifications, changes, or substantial
removal of organisms, resources, or material
Protection of landscapes and nature from use Eliminate human impacts altogether
preservation
Protection of natural resources for
proper/appropriate use of nature
Regulate human use
conservation
Conservation is about asserting (or reasserting) certain
values in society concerning
the human/nature relationship
beliefs and ideas that inform assessments of
worth and which are, by definition socially constructed
values
Protected on basis of religious or spiritual grounds
natural sacred sites
sacred site example
Madagascar “Fadys”
Protected on basis of Rational Resource Planning
resource and game reserves
Protected on basis of recreational, social, and health
benefits for urban dwellers
country state and city parks
Areas protected for scientific endeavors, self improvement
through nature education, exercise in a natural setting, and
recreational amusement
nature monuments and nature reserves
Supported by the value that humanity has a moral
responsibility to save threatened life forms, and that the
needless slaughtering of wildlife is cruel and barbaric
wildlife sanctuaries and refuges
Different values for different countries – but most
revolve around a sense of national identity and nation building
national parks
Concept created by the Sierra Club (John Muir) and The Wilderness Society (Aldo Leopold) Desire to create legal definition of “wilderness” and define wilderness areas as part of American heritage
wilderness areas
`Community Based Natural Resource Management
(CBNRM) or Communal Conservancies
community conservation areas
are valuable for protecting low-impacted lands, migration routes, expanding total area of protected lands, connectivity between other protected lands (reducing fragmentation), and water quality buffers
conservation easements on privately owned lands
Goals of Protected Areas and
Landscape Biogeography
Protection in diverse ecoregions across the world
Protection along connected corridors within similar and between different ecoregions, protecting migratory paths Protection of both large and small areas Expanding boundaries of current protected lands Protecting new lands that don’t have current conservation
status Elevating conservation status of lands relative threatened or endangered species and habitats
Biological variation among species and biological elements, genetic variations; population, community and ecosystem dynamics. Types of species, number of species, how these species interact, and their ecological succession
biodiversity
biodiversity threats
overharvesting land cover changes fragmentation invasive species pollution climate change
Hunting, recreation, over exploitation of a species or resource
overharvesting
Natural to non-natural , loss of habitat
land cover changes
Presence of filters and barriers, loss of habitat
fragmentation
Competition for resources and habitat, predator-prey interactions
invasive species
Impacting the quality of ecosystems and their habitats
pollution
Impacts on geographic patterns of limiting factors and species adaptation responses to changes or loss of habitats
climate change
Preserve species distributions and in doing so, preserve the
ecological and evolutionary processes required to conserve
diversity, as well the natural character of nature
conservation biogeography
Conversion from one land cover to another Forest to non-forest Old-growth to second and third growth
deforestation and logging
Spatial patterns of species, their population, and their range extent declines prior to extinctions
geographic range collapses
most commonly caused by habitat loss/destruction from land cover changes, and competition or predation by exotic and invasive species
range collapses
Three R’s for guiding conservation strategies
representation
redundant
resilient
Design of conservation areas - the debate
SLOSS single large or several small
All biological features across a range of environmental
conditions should be represented in a system.
conservation planning representation
Representation of multiple populations or examples of the
features of interest
conservation planning redundant
Ecosystem occurrences must be of sufficient quality to
provide for long-term persistence
capacity of a system to resist damage and
recover from a disturbance
conservation planning resilience
Tool for identifying “gaps” in conservation lands
GAP analysis program
Large Reserve Advantages
Smaller edge habitat ratio to total core habitat Greater habitat diversity
Greater potential to support more species More wide-ranging, low density species and individuals More complete (and complex) trophic interactions Lower extinction rates Less required interference or maintenance
Several Small Reserves Advantages
Better habitat quality (less multi-use impacts of large
conservation lands) More populations of rare or target species (areas protected
because of endangered or threatened species) Lower risk of major infestations or catastrophic events Lower acquisition costs Easier to understand and describe more completely
Easier access to the site
Better suitability to public education and nature study
