Waterfowl and Climate Change:Issues and Implications

Sonja M. Smith

The Nature of the Problem• Increasing atmospheric concentrations of

greenhouse gases (CO2)…

The Nature of the Problem

• Rising global temperatures…

The Nature of the Problem

• Changing precipitation patterns…

The Nature of the Problem

• Rising sea levels,• Mounting climactic variability,• And, more (often) extreme climactic events…

The Nature of the Problem

• Anthropogenic land cover change further confounds the issue…

Morenci Mine, Morenci, AZ

Johannesburg, South Africa

Climate Change and Wetlands…• Important breeding grounds• Congregation sites throughout the year/migration• Important winter habitat• Biodiversity hotspots in arid regions

Basque del Apache National Wildlife Refuge, NM

Waterfowl• Provide important ecosystem goods, annually:

– 12 million hunting days– 46 million birders

• Integral component of natural ecosystems• Critical role in wildlife policy development

– National Wildlife Refuge System

Waterfowl and Climate Change• Coastal/Inland wetland habitat loss

– Breeding grounds– Migration corridors (flyways)– Stopover sites

• Timing/distance travelled during migration

Strong relationship between waterfowl & water conditions

The Migratory Flyways

• 1) Pacific• 2) Central• 3) Mississippi• 4) Atlantic

12

3

4

Pacific Flyway• Habitat loss from rising sea

levels/encroaching development

• ↓ snow accumulation and earlier snowmelt = ↓ summer water– 10-30 days earlier– 11% decrease in snowpack– Cascades: 30-60% decline in

snowmelt-derived water

Central Flyway• Water regulation/diversion (dams)

– Reduction in open channels/marshes– Sandhill Cranes, Whooping Cranes

• ↓ snowpack/higher temperatures– Limited water availability for humans/other species

• The Prairie Pothole Region

Mississippi Flyway

• Water/shoreline habitat loss in Great Lakes…– 19-39% decline in duck numbers

• Drop in water levels (up to 2.4’)– Decline in SAV

• Increasing contaminant levels• Gulf Coast sea-level rise 45%

coastal habitat loss• Canvasbacks, Redheads, Lesser

Scaup

Atlantic Flyway

• Sea-level rise (up to 15”) confounded by development

• Canvasback, American Black

Duck, Northern Pintail, American Wigeon, Greater & Lesser Scaup, Ring-necked Duck, Green-winged Teal, Mottled Duck, Wood Duck, Fulvous Whistling Duck, Tundra Swan

Chesapeake Bay• One of the top wintering waterfowl areas in

N. America– >1 million waterfowl

• Exacerbation of pollution effects

• Decline in SAV– Degradation in water quality– Warming temperatures– Increasing human population

• Area already abandoned by Northern Pintail, Redhead, American Wigeon

North America’s duck factory

Prairie Pothole Region

PacificFlyway

CentralFlyway

MississippiFlyway

• 10% breeding habitat• Produces 50-80% N.

America’s ducks• >75% harvested ducks

Climate Projections

• Palmer draught severity index (PDSI)– GCMs and sensitivity simulations to predict

habitat conditions/project future duck numbers

• Correlation between:– pond numbers and PDSI– breeding duck numbers and PDSI

• 2020s: mild drought, PDSI = -1.41– May pond numbers decline by 23%– Duck population decline by 26%

Climate Change and the PPR

Climate Change and the PPR

• 2050s: moderate drought, PDSI = -2.59– May Pond numbers decrease by 38%– Duck population decline by 46%

Northern forest/tundra (CAN and AK)• 20% N. American breeding waterfowl• Wintering habitat for 50% Pacific Flyway birds• Arctic region is the fastest warming• Loss of important tundra habitat• Lesser Scaup, Surf Scoter, White-winged Scoter

Migration

• Species expected to skirt their ranges northwards and eastwards

• Shift in wintering areas– i.e., Lithuania Mallards

• Shortening migration routes

• Take-off/Arrival times noticeably earlier

Effects on waterfowl

• Decrease breeding frequency• Reduce clutch sizes• Shorten breeding season• Decrease re-nesting frequency• Decrease nest success• Lower brood survival• Lower recruitment + constant mortality =

declining populations

Management Implications• Climate change is detracting

for many waterfowl species, but…

• Habitat loss/other related anthropogenic effects on the environment confound this!

• Repercussions of habitat loss and climate change may be mitigated by the distribution of remaining habitat …

Management Implications

• YOU as future managers:• Predict areas important

for waterfowl in the future

• Set aside larger areas, buffering zones

• YOU as citizens, hunters, bird-watchers…

Ducks Unlimited• Grassroots, volunteer-based organization• Conserves, restores, and manages wetlands and

associated habitats for N. America’s waterfowl• 792,638 members (as of 1 January 2008)• 12,283,871 acres since 1937• $2.70 billion since 1937• http://www.ducks.org/conservation/

Ducks Unlimited

Acknowledgements

• Dr. Bill Mannan• Geoffrey Palmer• Clay Bowers

Questions?