What are the potential impacts of climate change on fresh water recreational fishing opportunities in the U.S.?

Presentation to:

Water Ecology and Climate Change Workshop

Susan Herrod Julius

Global Change Research Program

June 15, 2001

National Center for Environmental Assessment National Center for Environmental Assessment

MN MI WI ILL IN OHTotal Angler Exp $1,875 m $1,506 m $1,072 m $1,568 m $799 m $836 m

Total Economic Impact $3,678 m $2,854 m $2,138 m $3,618 m $1,677 m $1,879 m

# Anglers 1,538,180 1,823,534 1,473,561 1,351,047 992,420 1,231,445

# FW Anglers 1,420,525 1,310,695 1,232,103 1,123,401 862,646 907,729

# Great Lakes Anglers 48,274 674,200 180,652 259,642 59,616 425,555

Total Fishing Days 27,002,340 28,708,731 17,130,434 20,459,075 15,810,948 17,848,215

Great Lakes Fishing Days 162,718 6,084,370 850,474 1,542,490 786,862 3,539,390

Source: American Sportfishing Association Fishing Statistics – 1996 Sport Fishing Participation and Economic Impact

Background: Recreational Fishingin the Great Lakes

EPA Global Change Research Program

EPA Global Change Research Program

Background: Purpose and Scope

• Purpose: explore magnitude of potential societal impacts• Scope:

– Limited factors of analysis for tractability• Recreational fishing• Temperature effects• Rivers and streams

– Estimated effects of climate change on ranges of fish species across US

– Used effects on fish ranges as inputs to an economic model– Conducted sensitivity analyses to examine robustness of

results and insights

EPA Global Change Research Program

Approach: Baseline Water and Air Temps

• Identified a sample of 996 sites

• Developed relationship between air temperature and water temperature

EPA Global Change Research Program

Approach: Thermal Tolerance

• Used data on weekly maximum temperature tolerance reported by Eaton and Scheller

– Fish and Temperature Database Matching System (FTDMS) provides tolerance based on 95th percentile weekly average water temperature for most species

– For species whose ranges extend south of US-Mexico border, tolerance based on Upper Zero Net Growth (UZNG) temperature

• Evaluated ranges of 31 species

EPA Global Change Research Program

Approach: Thermal Tolerance

Cold Water Upper Thermal Species Tolerance (oC)

Chum salmon 19.8Pink salmon 21.0Brook trout 22.4Mountain whitefish 23.1Cutthroat trout 23.3Coho salmon 23.4Chinook salmon 24.0Rainbow trout 24.0Brown trout 24.1

Upper ThermalOther Species Tolerance (oC)

Northern pike 28.0Walleye 29.0Pumpkinseed 29.1Yellow perch 29.1Smallmouth bass 29.5Black crappie 30.5Flathead Catfish 34.0Channel Catfish 35.0Largemouth bass 35.5Bluegill 36.0

EPA Global Change Research Program

Approach: Fish Presence• Identified baseline ranges of fish, by state

Number of species <9 9-11 12-15 16-19 20-23 24-27

Number of Species Present: Baseline

EPA Global Change Research Program

Approach: Effects of Climate Change onFish Presence

• Used General Circulation Models (GCMs) projected changes in air temperature

• Juxtaposed projected increments to air temperatures with locations of sample stations

• Based on air temperature/water temperature relationship, predicted future water temperatures

Results

•Many states lose significant proportions of existing cold water habitat

•Across guilds, 21 of the 48 states lose 1 or more of the 31 species

EPA Global Change Research Program

Loss of Habitability for Cold Water Species

Brook Trout Brown Trout Rainbow Trout

Chinook Salmon Chum Salmon Coho Salmon

Not present in baseline 0% 1-49% 50-99% 100%

Percent of available habitat lost

Results

• More tolerant species lose less habitat

EPA Global Change Research Program

Largemouth Bass Northern Pike

White Crappie Channel Catfish

Not present 0% 1-49% 50-99% 100%in baseline

Percent of available habitat lost

Loss of Habitability for Selected Species

EPA Global Change Research Program

Economic Assessment:Vaughan and Russell Model

• Estimate changes in fishing due to changes in water quality

• Three-stage estimation:

– probability of general fishing participation

– conditional probability of participation by fishing category

– average days per angler devoted to types of fishing

• Stream reaches are uniquely assigned to fish guild categories based on highest value

• Changes in participation days are estimated and valued using unit value approach

EPA Global Change Research Program

Economic Assessment:Key Assumptions and Parameters

– Each fishable acre is uniquely assigned to highest valued use allowed by thermal conditions

– Population, socioeconomic characteristics and participation rates held constant over the modeling horizon for baseline and climate change scenarios

– Fishing values held constant over the modeling horizon, with and without climate change

– No distinction is made between net WTP for stream- and for lake-fishing

Effect of Assumptionson Economic Impacts

?

Assumptions

EPA Global Change Research Program

Economic Assessment:Results

• Estimates of economic impacts for recreational fishing range from damages of $320 million per year to benefits of $81 million per year (1993$)

• Cold water fishing losses range from $1.3-$3 billion per year

• In 32 of 42 scenarios conducted, damages result from habitat changes

• Highest sensitivity is to assumption about cold water acreage substitutability:

– damages increased across all scenarios

EPA Global Change Research Program

Economic Assessment:Sensitivity Analyses

(Dam

ages

) or B

enef

its in

Mill

ions

of 1

993

Dol

lars

per

Yea

r

(2,000)

(1,500)

(1,000)

(500)

-

500

1,000

1,500

Maximum

Average

Minimum

PrimarySpecification

High value;no sub

Primary value;no sub

High climate sensitiv.

Highvalue;no ww

increase (SA&GC)

High value

Low value; no sub

Low tolerance Wide

screen

Primary value;no ww

increase (SA&GC)

Lowvalue;no ww

increase (SA&GC)

Low value

Low climate sensitiv.

High tolerance

Annual Economic Welfare Effects by Sensitivity Runand General Circulation Model

EPA Global Change Research Program

Conclusions• In a warmer world, fish losses are likely, particularly for cold

water species

• Climate change is not as immediate as some other threats to fisheries, but it is likely to result in additional stresses

• Socioeconomic impacts could be significant

• “Fishes are an excellent indicator of the expected changes from Global Warming”

– Protecting the ecosystem services of the Great Lakes will require all users, commercial and recreational, to work together to understand the effects and identify management solutions