Download Influence of Wetland Restoration on Native Pollinator Communities

Influence of Wetland Restoration
and Adjacent Watersheds on
Native Pollinator Communities in
the Rainwater Basin
Project Proposal
Cynthia Park
Overview
• Introduction
o Importance of pollinators
o Concern about pollinator decline
o Wetlands and prairie as pollinator habitat
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Playa wetlands in the Rainwater Basin
Effects of land use on habitat
Objectives and methods
Implications of study
Importance of Pollinators
• 75 – 90% of our planet’s angiosperms rely on
pollinators to assist with reproduction
o 25,000-30,000 species of bees alone are obligate flower visitors
• Contribute to the biodiversity of the planet
• Humans rely on many pollinated plant species
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Food
Fiber
Drugs
Fuel
Recreation
Aesthetics
Importance of Pollinators
Importance of Pollinators
• Economic value
• Many crops require
direct pollinator
services
• Indirect pollinator
services such as forage
material for livestock
• Global value estimated
at $122-200 billion/year
o $15.12 billion in the United
States alone
Concern about Pollinators
• The need is only increasing
• Pollinator populations cannot keep up
• Massive loss of domestic honeybee populations
o 59% in one year alone
• Decreasing trends of wild pollinator populations
o Serious need for documentation of species declines
Reasons for Decline
• Low biodiversity
o Poor diet
• Stress
o Frequent moving long
distances
o Sudden changes in
environment
• Parasites
Reasons for Decline
• Loss of complex floral
communities and
nesting habitat
• Agricultural cultivation
• Potentially harmful
pesticides
o Can directly weaken or kill
o Indirectly harms by removing
food and habitat
Potential Habitat
• Highly mobile species
• Can persist in small,
fragmented areas
• Pollinators can benefit
from adjacent areas of
natural habitat
Rainwater Basin Habitat
• Great Plains grasslands
are one of the most
endangered
ecosystems in the world
• Landscape has
completely been
altered
o Soy and corn production
• Playa wetlands and
prairie uplands may be
some of the only areas
with necessary
resources
Playa Wetlands
• Crucial ecosystems for the Great Plains
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Recharges the aquifer
Improves water quality
Carbon sequestration
Source of biodiversity
• Each playa exists in its own watershed
• Only receive water from precipitation and
catchment runoff
• Highly influenced by upland usage
Wetland Reserve Program
<10% of playa wetlands remain
Crucial in protecting natural habitat
Takes land out of crop production
Enhances, restores, or protects wetlands and
immediate watersheds
• RWB focuses on habitat and food resources for
migrating waterfowl
• Secured > 17,265 ha of playas
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o > 75% are WPAs and WMAs
Effects of Land Use
• Hydroperiods are effected by watershed size/slope,
vegetation, and soil
• Row crop agriculture has led to more sediment
accumulation than can be naturally removed
o Exposed sediment
o Reduces floral biodiversity in catchment
o Fewer pollinator resources leads to less pollination and an even greater
decline in some plant species
Effects of Land Use
• Uplands of undisturbed grassland can provide the
necessary habitat requirements
o More beneficial forbs
o Nesting habitat
• Creates a buffer strip around the wetland
o Reduces erosion
o Increases soil permeability
o Less runoff
Comparison with WRP sites
• Engineered restoration
o Sediment removal for seed bank
o Planted buffer strip
• Similar species richness, but different plant guilds
o More mud-flat annuals
o Less wet prairie and deep emergent perennials
• Doesn’t seem to be moving towards reference
conditions
o Inability for perennials to disperse as easily
o Current annual plant community preventing establishment
o Maybe restored sites haven’t had enough time
• How does this affect the pollinator community?
Objective 1
• Examine the effects of watershed land use and
wetland presence on pollinator populations across
three different land use types
o Cropland
o WRP sites
o Reference state
Hypothesis
• Pollinator diversity is going to depend on floral
communities
• Agricultural sites will
contain the least amount
of pollinator biodiversity
• Reference state and WRP
sites will contain the
greatest abundance and
biodiversity
o Different pollinator communities
Methods
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27 sites across 3 land uses
Sample 28 times over 2 years
Bi-monthly from April - October
Each site will contain 3 wetland and 3 upland
transects
o 25 m long by 0.5 m wide
Methods
• Blue vane traps
o Set half way down each transect
o Set out in the morning (0900-1100) for 24 hour exposure
o Set at the height of the vegetation with wooden stakes and galvanized
wire
o Place lid on trap to contain insects
Methods
• Sweep netting
o Walk the transect, randomly sweeping back and forth (0.5 m)
o 30.5 cm hoop aerial insect net
o All insects were placed in a kill jar, then into a single collection bag
• Selective sweeping
o Adjacent transects placed 10 m next to sweep net transects (25 m long
by 2 m wide)
o Collect individual pollinators on individual plants
o 6 minutes for each transect
o Pollinators collected are placed in individual vials with each plant species
Objective 2
• Compare seasonal changes in the floral community
and pollinator populations in playas and their
uplands among native grassland, WRP and
cropland
• Track seasonal shifts in pollinator important plants
throughout the season
Methods
• Step point intercept method
o Walk the general sweep netting transect and identify plants found
touching the tip of my right boot at each step
• Twice a season
o Mid-June and mid-August
• Observe water level differences
• Herbarium presses were used to collect unknown
species
o Identified using The Flora of Nebraska or with the help of Nebraska Game
and Parks employees
Objective 3
• Integrate information with past and on-going
research on major ecosystem services provided by
depressional wetlands in Great Plains
o Comprehensive understanding of playas
• Integrate Land Model with USGS
o Forecast change in ecosystem services
• Collaborated protocols with other studies
o North Dakota and Texas
Implications
• Determine if RWB wetlands and surrounding uplands
are providing pollinator habitat
• Provide decision makers information to direct
conservation and restoration efforts
o Encompass all ecosystem services
• Develop a better understanding of pollinator
communities and habitat needs
Acknowledgements
• Environmental
Protection Agency
• Nebraska Game and
Parks
• Oklahoma State
University
• Loren Smith
• Angie Begosh
• Dale Daniel
• Lydia Horne
Questions?