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Two Summer Research Assistant Positions in Plant/Pollinator Evolution and Conservation
Position 1: Part time, on campus, to evaluate divergent selection on floral traits by pollinators (mostly bees) and water availability. Position 2: Full time, Vancouver Island, to assist in building pollinator interaction webs and measure pollen limitation of wildflowers in the endangered Garry Oak Ecosystem.
Both begin mid-April and run through July (flexible at both ends)
To Apply: Send a letter detailing which position you are interested in and why you should be hired, plus a CV including contact information for two references, to Elizabeth Elle: [email protected].
SCHEDULE FOR NEXT 2-3 weeks -
F- Restoration
M- Reintroductions
W- Background for issue based tutorial
not attending will reduce ability to participate in the tutorial
Guest – CWS – Habitat approaches
attendance required
New topic - Reserve Design
RESTORATION terminology natural succession vs active management case studies
REINTRODUCTIONS Why and when? Australian and New Zealand perspectives Canadian reintroductions The good, the bad and the ugly
ECOLOGICAL RESTORATION
CURRENT STATE OF SITE
Reclamation Rehabilitation Re-creation Restoration
Improve Return to historic condition
Replacement
Restore structure, function, diversity and dynamics of ecosystem
DESIRED STATE OF SITE
Stabilize Remove pollutants Revegetate Aesthetics
RESTORATION TOOLS
Natural succession - let nature take care of it
Mitigating/altering factors impacting the site
Introducing and promoting species
NATURAL SUCCESSION
Eg Restoration of Tropical Montane Forest,
Goal restore composition structure function prevent spp loss and maintain viable populations
Options 1)!Allow natural regeneration 2)!Plant native trees, then allow succession
Restoration of Tropical Montane Forest
Ucumari Regional Park, Central Andes, Columbia
Degraded - cattle ranch, pasture, logging
NATURAL INTERVENTION REGENERATION Plant native
Andean alder 40 yrs later
Ecoregion with enormous diversity
Ucumari Regional Park, Central Andes
NATURAL AND TREE PLANTATIONS
Alder dominated canopy No sub-canopy 43 spp per 0.125 ha plot
Mixed uneven canopy Continuous vertical foliage 63 spp per 0.125 ha plot
178 spp found in restored plots Only 23 shared by two forest types
Initial conditions determine restored ecosystem Natural succession --> greater diversity BUT success depends on availability of seed sources
NATURAL SUCCESSION
Restoration of Fresh Kills Landfill, NY City
•!Received urban waste for 50 yrs
•!Created four mounds 100+ ft tall
•!Mounds “capped” 2001
Goal Restore wetlands,grasslands and woodlands that will offer wildlife habitat and natural open spaces
Restoration of Fresh Kills Landfill, NY City
Natural regeneration ---> little structure, diversity
Planted shrubs, oak, pine (17 spp) ---> arrival 20 new spp. in 2 yrs
Planting adds spp, provides habitat that allows arrival animal-dispersed seeds
Fresh Kills 2016
NATURAL SUCCESSION
Proportion of ancient forest left
Herb species diversity in regenerating forest
Vellend 2003 Ecol 84: 1158-64 Q. Conclusions?
RESTORATION - mitigating impacts on a site
Steps: 1.! Define Goal - restore what? 2.!Identify constraints
Disturbance regime Lack seed source/limited spp pool Invasive spp - biogeochemical feedback Herbivory or other trophic interactions Environmental change
5.!Prioritize - 6.!Address Constraint 7.!Evaluate and GO TO 1
Restoration of tropical dry forest, Guanacaste Conservation Area, Costa Rica
Issue - conversion of forest for pasture
- dry forest is the most endangered lowland forest type
- less 0.1% original habitat is protected
Daniel Janzen
Restoration of tropical dry forest, Costa Rica
Guanacaste - major restoration project
- 47000 ha pasture + 23000 ha park
- 130 staff
Restoration of tropical dry forest, Guanacaste Conservation Area,
Costa Rica
Constraints - fires set to maintain pasture - pasture dominated by exotics
- seeds are animal dispersed
Prioritize
Step 1 - aggressive fire control; fire breaks, fire access roads
Step 2 - horses/cows used to promote seed dispersal
Restoration of tropical dry forest, Costa Rica
Results Areas protected 5-10 yrs
- Fires reduced by 93% - trees 10-15 ft tall
Pasture expected to be closed canopy forest in 20-50 yrs mature forest in 300 yrs
Restoration of Garry Oak Ecosystems
High diversity Native wild flowers
BUT dominated by exotics (grasses/broom)
Restoration constraints: invasive spp, grazing, fire
Evaluating constraints: an experimental approach
1.! Plants compete with each other for resources “Bottom-up hypothesis”
2. Herbivores regulate plants “ top-down hypothesis”
3. Herbivores eat certain plants which helps less palatable species “enemy of my enemy hypothesis”
Emily Gonzalez – UBC
200 plots in Southern gulf and San Juan Islands
Many deer
Few deer
200 plots in Southern gulf and San Juan Islands
Evaluating constraints: an experimental approach
Plant native species in plots Seeds Seedlings
Treatments Herbivore exclusion, Competitor removal Fence Cut Factorial 2x2 design
Gonzales and Arcese Ecology 2009
Competition (C) and Herbivore (H) impacts on seedlings and seeds
Evaluating actions: an experimental approach
Removal of competitors (burn or mow) Re-seed with natives
Control Burned Seeded Both
300
200
100
0
No.
See
dlin
gs
Added
Non-added
exotics
Burning can help some natives but it helps some exotics too MacDougal and Turkington Ecology
Restoration of tall grass prairie
Tall grass prairies covered 250 million acres of Midwest dominated by 30 grass + 250 forb spp 1% remaining most endangered ecosystem in NA
Midewin National Tall Grass Prairie projected initiated 1996 19,000 acres in Illinois massive restoration project
Midewin National Tall Grass Prairie
Action - removal excess willow/cottonwood - plantings 69000 plants, 79 sp - seeding - 112 spp
RESTORATION ECOLOGY
New discipline Active research - how to assemble a community
order effects, trophic interactions Requires
multidisciplinary approach clear goals community involvement planning $$$
ANIMAL RESTORATION PROJECTS
Once habitat is restored
How successful are (re)introductions of animals?
REINTRODUCTIONS - OVERVIEW Terminology Why and when? Australian and New Zealand perspectives Canadian reintroductions The good, the bad and the ugly
TERMINOLOGY
Reintroduction - introduce into historic range
Translocation - movement from A to B
Supplementation/reinforcement
Benign introduction - introduce outside known range
Loggerhead shrike
takahe
REINTRODUCTIONS - Why and When?
Why maintain/restore biodiversity re-establish keystone taxa establish viable wild populations limit long-term management costs
When need to increase number or range no risk to source population cause of decline removed sufficient protected habitat community support impact on people +ve $$$
IUCN guidelines
REINTRODUCTIONS - Can they work?
Famous success stories
Mauritius kestrel 1974 - 4 birds 1994 333rd release 2000 ca. 700
Golden lion tamarin 1970’s 200 147 captive bred releases 2001 - 1000 % wildborn now 88%
REINTRODUCTIONS - Will they work?
Wolves in Yellowstone
Cause of extirpation
Human hunting
Reintroduction
1995-97 41 individuals
Current population in YNP - 271+
Prospects No longer “endangered”
REINTRODUCTIONS - Will they work?
The Guam rail
Cause of extirpation
brown tree snake (introduced)
Reintroduction
Rota - predator free island Guam - 60 ha fenced area
Prospects on Guam - not good
REINTRODUCTIONS - Will they work?
MOST IMPORTANT CONSIDERATION
What caused extirpation in the first place?
Has that threat been reduced/eliminated
NEXT LECTURE Reintroductions Australian and New Zealand perspectives Canadian reintroductions The good, the bad and the ugly