Concepts & Definitions Flashcards
Managing endangered species paradigms
- SMALL POP PARADIGM = focus on STOCHASTICITY events that effect pop dynamics and make small pops susceptible to extinction
- PVA to estimate viability over time - DECLINING POP PARADIGM = focus on DETERMINISTIC (non-random) process
- human-caused stressors (habitat loss/frag, overharvest, pollution, climate change)
Forces that drive pop declines aren’t necessarily the same that drive to extinction. Manage for both.
PVA
POPULATION VIABILITY ANALYSIS = use of data/models to estimate persistence over time
- Model pop dynamics
- Include stochasticity (variation in demo parameters)
- Simulate dynamics cumulatively (threshold size, MVP)
E.g. northern spotted owl, modelling showed higher probability of decline with logging
COSEWIC
COM ON STATUS OF ENDANG WILDLIFE IN CANADA
Assessment:
- Doc species diversity & distribution
- Intraspecific diversity (designatable units, geo/gen distinct)
- Decide who needs assessment
- Quantitative criteria (IUCN)
- abundance, range, trend, gen div - Quantitative analysis (PVA, etc)
- Advice Min of Envt/CC
- If listed, immediate protections
- If listed, develop recovery plan
- scientific, inform SARA (political)
- only 18% improve
Failure in protecting endangered species
- jurisdictions
- BC lacks law protecting SAR
- delays/failure to list
- critical habitat not protected
- no prioritization
- little funding
Proposed oversight committee to coordinate planing/action between COSEWIC/SARA & provincial mgmt, monitor, etc
Large carnivores
Threats
- habitat (e.g. lions savannah to ag in Ghana)
- conflict
- prey depletion
- utilization
Vulnerabilities
- range (e.g. wolves/deer Algonquin)
- energy
- low density
- slow life history
- low intrinsic rate of growth
- conflict
- difficult to survey
Umbrella species
Trophic downgrading
Loss of upper trophic consumers changes community structure & ecosystem function
E.g. wolves > deer > forest underbrush
Large carnivore conservation measures
- harvest mgmt
- protected areas (strengthen, expand)
- mitigate conflict
- translocation, reintroduction, captive breeding
Harvest managment
- Avoid overharvest
- Promote societal benefits
- Maintain ecosystem services
Yield = # individuals produced by population (overall growth, not growth rate)
MSY
Fixed-quota vs fixed-effort harvest
MSY
Maximum Sustainable Yield = largest yield taken indefinitely
Harvest management systems
Fixed-quota harvest
- if harvest < recruitment, pop inc to equilibrium
- if harvest > recruitment, pop declines (extinction or stable eq)
- danger if harvest near MSY
Fixed-effort harvest
- proportional quota, % of N
- danger if harvest exceds max intrinsic rate of growth
GRAPHS:
- Pop size vs Yield
- parabola
- harvest = horizontal line (fixed-quota), diagonal line (fixed-effort)
- 1 unstable, 1 stable equilibrium
Harvest management tactics
- season timing/duration
- area regulation (Pop Mgmt Unit)
- control effort = licenses, bag limits, lottery, etc
- age/sex restrictions
- weapon restrictions
- “fair chase” (calls, lights, bait)
Restoration
RESTORATION = act of returning degraded to former condition
ECOLOGICAL RESTORATION = PRACTICE of restoring degraded ecological system
ACTIVE / PASSIVE = manipulation or not
RESTORATION ECOLOGY = process of developing THEORY to guide
- includes niche theory, pop dynamics, energy flow, community structure, etc
Paths to restoration
- Habitat restoration
- wetlands, corridors, fire regimes
- Bonn Challenge
- assumes “they will come” - Population reintroduction/aug
- has threat been removed? - Remove invasive species
- e.g. marbled murrelet & Norway rats on Langara - Restore large predators, ecosystem engineers
Reference conditions
A/biotic conditions, goal
Pre-settlement or Pleistocene rewilding
Difficulties = data, modern acceptance, identify cause, monitor
Alt stable states
Novel ecosystems = diff ecological composition & function due to changing species & envt
Life tables
LIFE TABLE = tool to analyze age-specific vital rates (fecundity, mortality, survival, etc)
Static life table = snapshot
Cohort life table = follow group, fecundity + mortality
Net reproductive rate = sum of survival * fecundity (lx * mx)
R > 1 pop inc
Fecundity
mx = # of female live births per female per unit time
Matrix population model
= bookkeeping of birth/survival using transition probabilities and matrix algebra
Leslie matrices = age-structured model of pop growth
Life history strategies
LIFE HISTORY = set of adaptations that influence survival and fecundity
- lifespan
- survival rate of diff ages
- age at first repro
- # offspring/litter
K-selected = large, slow mature, low fecundity, high survival (competitive at K)
r-selected = small, opposite (maximize pop growth rate, r)
Survivorship curves
Type 1 (backwards r) = humans Type 2 (\) = many birds Type 3 (slide) = fish
Population regulation & limitation
POP REGULATION = process of returning to K
- density-dependent factors (competition, territoriality, disease)
POP LIMITATION = … determining K
- density in/dependent limiting factors (severe weather)
Density-dependent pop growth
- Logistic “S” curve (time vs N)
- Growth rate declines as pop increase
Population growth models
GEOMETRIC growth = discrete steps
- lambda = per capita growth rate from N1 to N2 (>1 inc)
EXPONENTIAL = J curve
- bacteria, mice
- r = instantaneous growth rate
- rmax = intrinsic rate of growth
LOGISTIC = S curve
- up to K, density-dependence
- wildebeest/rinderpest, yeast
THETA-LOGISTIC = backwards r
- rate slows at higher density
Intrinsic rate of growth
rmax = max rate of inc in exponential growth (optimal conditions, constrained by phsyiology)
Don’t want harvest to exceed rmax in fixed-effort harvest approach
Estimating abundance
- Complete count
- Distance sampling (transect/point)
- CMR (ie. Lincoln-Petersen single recapture)
- Indices (indirect)
- Assumptions
- Probability of detection (p)
- Detection bias (habitat, behavior, density)
- Accuracy & precision
Protected Area failings
- Not representative
- Too small (Spec-Area Rel’p)
- Too isolated (rescue effects)
- Overcrowded/human use
- Lack enforcement/funding
- Lack community support
Island Biogeography
GRAPH
- # species vs rate
- immigration (near higher curve)
- extinction (small higher curve)
- far, small supports smallest pop
Numerical & Functional Response
Responses of predators to inc prey abundance
NUMERICAL = inc # of predators
FUNCTIONAL = change in predation rate/behaviour (kill more per individual, bears eating only salmon head)
E.g. wolves move faster & into caribou habitat
Disturbance-mediated apparent competition
APPARENT COMP = two species neg. affect each other through interaction with common predator
Disturbance of habitat (cc/forestry)
> More forage for deer/moose
> Inc # of wolves
> Inc predation on caribou
Caribou recovery
- Habitat protection & restore (65% undisturbed goal, partial retention)
- Inc harvest effort for moose/deer
- Cull wolves
- Caribou protection (maternal penning, supplemental feeding, translocation)
- longer term, adaptive management needed
- ecological, economic, cultural, political issue
Trophy hunting vs ecotourism
- More widespread benefits (bushmeat, not just few jobs)
- Better for remote locations
- Smaller footprint
- Management for larger populations
Trophy concerns:
- sustainability
- age/sex ratio
- ethical (canned lions)
- distribution of revenue
Keep all options on table
(Di Minin et al., 2016)
Namibia conservancies
Community-based nat. res. mgmt (CBNRM)
- communal conservancies (20%, ’90s)
- diff from National Parks
Benefits
- biodiversity, abundance & range
- revenue ($2k per species)
- jobs
- bushmeat
- plant products
Mallard adaptive management
USFWS of sport harvest ducks
Collaboration of managers & scientists
(Nichols et al., 2007)
STRUCTURED DECISION MAKING
- Set objectives
- Set of mgmt actions (3 levels of regulation)
- Models of system response (diff in mortality & recruitment)
- Monitoring (aerial, ground, banding)
Success:
- reduced uncertainty
- maintain population
- public support
Structured Decision Making
Process
- Set objectives
- Set of mgmt actions (3 levels of regulation)
- Models of system response (diff in mortality & recruitment)
- Monitoring (aerial, ground, banding)
Success:
- reduced uncertainty
- maintain population
- public support
(Nichols et al., 2007) Mallards USFWS
Uncertainty in wildlife mgmt
COUV
Uncertainty, variation, control, observe
- Ecological uncertainty = mechanisms/response of system
- Environmental variation = stochasticity, natural fluctuations
- Partial controllability = mgmt actions indirect, response uncertain
- Partial observability = response estimated
Experimental management design
- Object/question
- Controls (BACI)
- Replication
- Randomization
E.g. northern spotted owl & barred owl removal in CA
- BACI design
- extirpation declined after barred owls removed
Adaptive management
Cycle - plan, do, evaluate
MGMT HYPOTHESIS = quantitative, measure against alts
MODEL LIKELIHOOD = prob of observed data matching model
E.g. exponential, logistic, theta-logistic curve
- density vs growth rate
- logistic = \
- geometric = –
- theta-logistic = backwards r
Working lands conservation
= landscape matrix
= supports biodiversity
= relies on biodiversity for ecosystem functions (sustainable production, water, connectivity, etc)
E.g. strawberries + orchards, hedgerows, natural areas
(Kremen & Merlender, 2018)
Managing for coexistence
- Less of them = lethal control, fertility control, exclusion (fences)
- Move them = translocation
- Move themselves = aversion conditioning, chemical repellants, diversion, habitat manipulation (remove attraction)
- Educate people
E.g. Canmore, AB
- remove attractions
- Wildsmart
- trail closures
- aversive conditioning
Demographic & genetic rescue
Connectivity, populations require exchange of dispersing individuals
DEMO RESCUE = immigration to maintain N
GENETIC RESCUE = immigration to maintain genetic diversity or effective population
E.g. Greater sage grouse
SARA Endangered
- restricted ranged
- pop/leks declined
- causes = habitat frag, oil & gas/ag
Recover Strategy (COSEWIC)
- protect lek habitats
- augment population
- reduce accidental mortality
- reduce predation
- monitor
E.g. northern spotted owl
Endangered in BC
- old growth, cavity nester
- causes = habitat loss
PVA
- greater probability of decline shown in PVA modeling
Lethal removal of barred owls in CA (BACI design) > territorial expansion
4 BC Wildlife Act species
Van Is marmot
Sea otter
Am. white pelican
Burrowing owl
BC endangered wildlife legislation recommendations
- Oversight Committee
- adaptive approach
- Recovery Teams to prioritize actions
- monitoring & reporting
E.g. caribou
IUCN Vulnerable
- slow life history, lichen old growth
- cultural keystone
- 11 design units in Canada, all declining (3 in BC)
- land-use conflict with oil & gas
THREATS = habitat loss, increased predation (disturbance-mediated apparent competition)
RECOVERY
- habitat protect/restore
- increase moose harvest
- cull wolves
- caribou protection (maternal penning, feeding, etc)
Billion Dollar Caribiou
(Hebblewhite, 2017)
- conservation triage, too costly to protect habitat
- legislation doesn’t work retroactively
Non/heritable changes
Some animals will adapt to climate change
Nonheritable changes (plastic) = physical traits not passed down
Heritable = coded in DNA
- E.g. tawny owl colour
Allen’s rule = Fennic fox ear’s shrinking
E.g. Columbian ground squirrel
later snow melt
compressed season
lower reproductive success
