Table of all major wetlands valuation theories

Listings of all major wetlands valuation theories

1: Economic Valuations

Theory or Approach Method Author and Year Value Location Notes

Revealed Willingness to pay:

Commercial fishing and trapping Costanza and Farber (1987) $486.25 per acre Terrebonnne Parish, LA Harvest and Yield Data

Revealed Willingness to pay Actual mitigation costs King and Bohlen (1994) See table 3 below

Revealed Willingness to pay Wetland Credit Sales See mitigation banking table

Expressed WTP Survey Results Hammack and Brown (1974) $25 - $85 per acre Recreation - travel cost method

Derived WTP Circumstancial Evidence, estimation Farber (1986) Wind Damage, Flood Protection

Non-Use WTP: Option Value Survey, donations, political Option value, Existence value

Energy Analysis GPP conversion Costanza and Farber (1985,1987)

Wetlands CANNOT be valued King (1998) Because the true economic cost cannot be measured yet, wetlands cannot be valued

2: Non-Economic Valuations

Theory or Approach Wetland Functions Author and Year Value Location Notes

Ecological Valuation King (1998)

Intrinsic Valuation Taylor (1981), Rolston (1982) environmental ethics

3: Revealed Willingness to Pay: Actual costs of mitigation

Study 1: King and Bohlen Study 2: Louis Berger and Associates, Inc.

Wetland Type Cost per acre (1997) Wetland Type Cost per acre (1997)

Aquatic bed $45,000 Emergent $43,675

Complex $95,000 Scrub/Shrub $124,144

Freshwater mixed $52,000 Intertidal emergent $415,007

Freshwater forested $124,000 Open water: emergent $273,7000

Freshwater emergent $84,000 Open Water: shrub/forest $130,220

Freshwater tidal $78,000 Emergent scrub/shrub $351,591

Salt Marshes $49,000 Emergent/intertidal $59,238

Mangroves $24,000 Emergent - forested $235,799

Prairie potholes $4,000 Riverine emergent $82,928

Other agricultural less than $1,000

4: Economic Value of Wetland Functions

Wetland function valued Number of studies Median Mean Range of means

Number Dollars per acre

Marketed goods:

Fish and shellfish support 8 702 6,132 7-43,928

Fur-bearing animals 2 na 137 13-261

Nonmarketed goods:

General-nonusers 12 32,903 83,159 115-347,548

General-users 6 623 2,512 105-9,859

Fishing-users 7 362 6,571 95-28,845

Hunting-users 11 1,031 1,019 18-3,101

Recreation-users 8 244 1,139 91-4,287

Ecological functions: 17 2,428 32,149 1-200,994

Amenity and cultural 4 448 2,722 83-9,910

Source: USDA - 1998

Theory or Approach	Method	Author and Year	Value	Location	Notes
Revealed Willingness to pay:	Commercial fishing and trapping	Costanza and Farber (1987)	$486.25 per acre	Terrebonnne Parish, LA	Harvest and Yield Data
Revealed Willingness to pay	Actual mitigation costs	King and Bohlen (1994)	See table 3 below
Revealed Willingness to pay	Wetland Credit Sales	See mitigation banking table
Expressed WTP	Survey Results	Hammack and Brown (1974)	$25 - $85 per acre		Recreation - travel cost method
Derived WTP	Circumstancial Evidence, estimation	Farber (1986)			Wind Damage, Flood Protection
Non-Use WTP: Option Value	Survey, donations, political				Option value, Existence value
Energy Analysis	GPP conversion	Costanza and Farber (1985,1987)
Wetlands CANNOT be valued		King (1998)			Because the true economic cost cannot be measured yet, wetlands cannot be valued

Theory or Approach	Wetland Functions	Author and Year	Value	Location	Notes
Ecological Valuation		King (1998)
Intrinsic Valuation		Taylor (1981), Rolston (1982)			environmental ethics

Study 1: King and Bohlen		Study 2: Louis Berger and Associates, Inc.
Wetland Type	Cost per acre (1997)	Wetland Type	Cost per acre (1997)
Aquatic bed	$45,000	Emergent	$43,675
Complex	$95,000	Scrub/Shrub	$124,144
Freshwater mixed	$52,000	Intertidal emergent	$415,007
Freshwater forested	$124,000	Open water: emergent	$273,7000
Freshwater emergent	$84,000	Open Water: shrub/forest	$130,220
Freshwater tidal	$78,000	Emergent scrub/shrub	$351,591
Salt Marshes	$49,000	Emergent/intertidal	$59,238
Mangroves	$24,000	Emergent - forested	$235,799
Prairie potholes	$4,000	Riverine emergent	$82,928
Other agricultural	less than $1,000

Wetland function valued	Number of studies	Median	Mean	Range of means
	Number	Dollars per acre
Marketed goods:
Fish and shellfish support	8	702	6,132	7-43,928
Fur-bearing animals	2	na	137	13-261
Nonmarketed goods:
General-nonusers	12	32,903	83,159	115-347,548
General-users	6	623	2,512	105-9,859
Fishing-users	7	362	6,571	95-28,845
Hunting-users	11	1,031	1,019	18-3,101
Recreation-users	8	244	1,139	91-4,287
Ecological functions:	17	2,428	32,149	1-200,994
Amenity and cultural	4	448	2,722	83-9,910


Source: USDA - 1998