lecture 7 ecology Flashcards
what is conservation biology
applying ecological theory to aid in biodiversity conservation
whats the approcah to conservation
provide scientific foundation for conservation decisions
whatsa the goal for conservation
slow, halt, or reverse the loss of biodiversity so it can improve.
global conservation
IUCN red list
what is the IUCN red list
list of species that are threatened with global extinction– assessment of individual species to decide if theyre threatend
what does IUCN sand for
international union for the conservation of nature
what characteristics does the red list look at
population sizes, trends, threates – and they categorize the species based on the extinction risks
IUCN red list categories
extinct, extinct in wild, critically endangered, endangered, vulnerable, least concern, data deficient, not evalulated
IUCN - extincy
no longer found globally
IUCN - extinct in wild
no longer found in the wild but are in zoo – captive areas
IUCN - critically endangered
most severe – imminent extinction – high risk of it. (extinction about to happen)
IUCN - endangered
threats are increasing, but may take longer compared to critically endganered
IUCN - vulnerable
also considered at risk of extinction – numeric balues of shrunken population – quantatative criteria
IUCN – least concern
“good” – no imminent risk of extinction
IUCN data deficient
not enough info – dont know risk, population
IUCN not evaluated
- labour intense process
- dont have time to evaluate every single species.
what three categories are considered to be at risk of extinction
critically endangered, endangered, vulnerable
around how many species have been assessed
only a fraction of amount of species in world – 166,000 – in world there is ~8.7 million
shortfin mako
lives in tropical and temperate distributions
current state is endangered – population size unknown
- threatened by overfishing
– both as a target (deliberate overfishing) and as a bycatch (accidental – lines in ocean set for other species catches mako instead).
sumatran rhinoceros
current statues – critically endangered – lives in south east asia
– about 30 mature individuals left \
–threatened by humans (hunting)
– distrubances (illegal logging, land conversion) – when the population size is really small – intervention might still not be enough
sea otter
current status – endangered
global population decreasing
– threats : oil spills, disease, climate change
in Canada what do they have
COSEWIC – committee on the status of endangered wildlife in canada – panel of scientific experts to identify and assess species at risk in canada.
what do the scientific experts measure/base extincion risk
population size, recent decline, threats to populations/habitats
COSEWIC categories
only one that applies globally – extinct – gone everywhere
extirpated, endangered, threatened, special concern,
COSEWIC - extrirpated
gone in canada but found elsewhere
COSEWIC - endangered
could be soon exgtirpated from canada – on its wat
COSEWIC – threatened `
could be soon endangered in canada – this category is what you need to focus you respurces on, so that you can plan an intervention
COSEWIC special concerns
vulnerable – current threats – not there yet, but keep an eyeout
COSEWIC assessments can be at the population level example
atlantic walrus – extinct in nova scotia, but special concerny in high arctic and low arctic – still population in canada, just diff populations are extinct
COSEWIC recommendations
you have the science advisory, and then the political decisions
– COSEWIC recommends listings on the species at risk act to the federal minister of environment and climate change – he makes the decision
COSEWIC recommendation mapping
top – recommendation – within 90 days – initial response – within 9 months – final decision – three potential decisions (send report back to COSEWIC - not enough info), (accept (SARA – species at risk act), (reject (no listing))
SARA
species at risk act – federal legislation
goals of SARA
- prevent extinction/extirpations of wildlife in canada
- plan for the recovery of endangered or threatened speaies
- must develop a management plan for listed species
conserving biodiversity the two levels
qspecies level, genetic level
species level conserving biodiversity
species in need of protection – all organizations (IUCN, SARA, COSEWIC)
genetic level conserving biodiversity
genetic diversity worthy of conservation – valuable, builds resiliance
how to conserve genetic diversity
- maintain a large population - preserve totaly genetic diversity – more pop more genes
- protect isolated populations (individual) – preserve unique genetic types – less exchange of genetic material but pool of diversity that is not found elsewhere
Ecosystem level IUCN red list of ecosystems
coral reef (caribbean) – endangered, Aral sea (central Asia) collapsed – almost nothing
benefits of biodiversity
ecosystem services
what does it mean by ecosystem services
benefits people obtain from ecosystems
list the services
provisioning services, regulating services, cultural services, supporting services
provisioning
supply the goods themselves, such as food, water, timber and fibre – foods, new medications, clean air and water
regulating
govern climate and rainfall, water (flooding), waste, and the spread of disease – keeps things habitable – erosion control and coastal protection, climate regulation, pollination
cultural
cover the beauty, inspiration and recreation that contribute to our spiritful welfare – recreational oppurtunities
– aesthetic, tourism
supporting
include soil formation, photosynthesis, and nutrient cycling which underpin growth and production – foundation of ecosystem
- biodiversity, nutrient cycling, primary productivity
monetary value
125$ trillion per year `
threats to biodiversity
habitat loss- (land conversion_
introduced species, overharvesting, pollution, overpopulation, climate change
impacts of threats
impacts both k and r
– lowers k (carrying capacity) – ex. habitat loss, reducing amount of habitat reduces carrying capacity for species that live in that habitat
- lowers r – negative r – per capita growth rate – population starts to decline – ex. otters and overharvesting
small populations are more likely to go extinct – why
sotchasticity, genetic problems
stochasticity
change (random) events – population size varies from year to year, therefore a fluctuation which is normal – if is no where near 0 individuals then it is fine – however, when it is near 0 – can drive pop to extinction – small populations may go extinct if there is a bad year
genetic problems
can arise in small populations – as population gets smalll, variability disappears – genetic drift.
– less able to adapt to changing environment
interbreeding
mating with relatives, can occur in small populations – therefore no diversity in the genes. – expression of deleterious alleles (harmful) – leads to reproductive problems
how small is too small
minimum viable population (MVP)
MVP
smallest population size that is likelt to persist into the future (future time period) (likely – probability)
effective populatyion size Ne
number of individuals that effectively participates in producing next generation, ALWAYS less than N
conservation of genetic diversity
not everybody gets to breed – sex ratio is not 50:50 – mating systems vary
