Alien Invasive
Species
Problem:
Net Effect =
Harm > Benefit
Solutions:
Managing species,
mostly people
Networks of Species Spread
Global Air Traffic as a Pathway
Intentional and Inadvertent Transport
Other Pathways
Other Pathways
Ecosystem Impacts and
Spread of Aquatic Invasive
Species
David M. Lodge, Mark Drew, Reuben Keller, John
Rothlisberger
University of Notre Dame
John Drake, University of Georgia
David Finnoff, University of Wyoming
Roger Cooke, Resources for the Future
Lindsay Chadderton, The Nature Conservancy
Alien Species in Aquatic
Ecosystems
San Francisco
Bay
Cumulative number of
species discovered
200
200
Great Lakes
150
150
Baltic Sea
100
100
5050
00
1850
1850
1875
1900 1925
1900
1950 1975
1950
Year
2000
2000
Shipping Network:
Great Lakes as the Beachhead
Voyages of 1 ship over 14 months
(from Holeck et al. 2004)
Great Lakes as the Beachhead
Great Lakes as the Beachhead
Round goby
Spiny water-flea
Dave Jude. Center for Great Lakes Aquatic Sciences.
VHS
Zebra mussel
Great Lakes Connections to
Global Shipping Network
12% of Global Ports connected by 1 degrees of separation
Great Lakes Connections to
Global Shipping Network
80% of Global Ports connected by 2 degrees of separation
Great Lakes Connections to
Global Shipping Network
99% of Global Ports connected by 3 degrees of separation
Great Lakes Connections to
Global Shipping Network
100% of Global Ports connected by 5 degrees of separation
Conclusions from Network
Thinking
•Great Lakes are connected to the rest of the
world’s ports with a few degrees of separation
•Temperate freshwater or estuarine species from
any port in the world are potential invaders into
the Great Lakes
•Through the Great Lakes, the global shipping
network connects to the recreational boater
network
•So what? What are the impacts?
Zebra and Quagga Mussels
• native to Black & Caspian Seas
• ballast water & hull
• first reported 1986
Limited Information available
on Impacts
Market costs: clog
water intake pipes
Non-market costs:
loss of native clams
Bird Studies Canada
Assessing Species
Impacts from
Shipping in the GL
Ecosystem
Services
Images courtesy US EPA Visualizing the Great
Lakes collection
Determining Impacts:
Structured Expert
Judgment (SEJ)
Sector
Nuclear Applications
European Commission
Community research
Project report
Nuclear science and technolo
Procedures guide for
structured expert judgment
Chemical & Gas Industry
Water pollution (ground and surface)
Aerospace sector/space debris
Health: Campylobacter & SARS
Volcanoes & Dams
“Expert judgment is sought when
substantial scientific uncertainty impacts on
a decision process.”
(Cooke and Goosens 2005)
EURATOM
Types of
Elicitation
Variables
• Commercial fish
landings
• Sport fishing effort
• Biofouling—raw water
uses
• Wildlife watching
What Sort of
Experts?
• Fishery biologists
• Industry reps (e.g., power,
shipping, angling)
• Environmental economists
• Leisure studies researchers
• GL food web ecologists
Who are our
Experts?
Richard Aiken (recreation economist, USFWS)
Renata Claudi (industry damages, Ontario Hydro)
Mark Ebener (fisheries, CORA, GLFC)
Leroy Hushak (economist, Ohio State U.)
Frank Lupi (economist, Michigan State U.)
Roger Knight (fisheries, Ohio DNR, GLFC)
Lloyd Mohr (fisheries, Ontario MNR, GLFC)
Chuck O’Neill (NY Sea Grant, industry damages)
Don Scavia (ecologist, MI Sea Grant, U. Michigan)
Roy Stein (ecologist, Ohio State U., GLFC)
·
Commercial Fish Landings
60
40
10
40
20
20
1
75
19
25
20
05
20
95
19
85
0
19
75
00
19
(Millions of Pounds)
Commercially Landed Fish
0.0
0.0
0.0
Expert Elicitation Background
b)
L.
Michigan
e) L. Data
Erie
10
i)
4
55
20
60
80
Lake 0
Michigan
00
Elicited Data and Calibration
Commercial Fishing
WITH NIS
WITHOUT
0
2
6
4
8
10
Commercially Landed Fish
(Millions of Pounds)
12
Combined Expert
Assessments and Impact
Distributions
2.0e-07
1.5e-07
WITH
NIS
1.0e-07
2006 Lake Michigan
Commercial Fishing
PERCENT
REDUCTION
0.0e+00
Probability Density
5.0e-08
62%
0.005
0e+00
1e+07
2e+07
3e+07
4e+07
2.0e-07
WITHOUT
NIS
1.5e-07
1.0e-07
5.0e-08
0.0e+00
0
0e+00
10
1e+07
20
2e+07
30
3e+07
40
4e+07
Commercially Landed Fish
(Millions of Pounds)
WO-WITH/
WITH
0.004
16%
0.003
0.002
0.001
0.000
-100
-100
-50
0
50
100
100
150
200
200
21
Percent Greater Without NIS
2006 Percent Reduction Distributions
Commercial Fishing
Sport Fishing
59%
9%
-100
- 100
- 50
13
0
50
100
100
150
57%
200
200
33
62%
62%
16%
2%
23
-100
62%
31%
62%
-100
30 100
200
14
68%
16%
21
18
1%
65%
59%
2%
-100
11
100
1%
200
-100
Wildlife Watching
51%
2%
- 100
-100
39%
- 50
1
0
50
100
100
15
100
200
100
200
Economic Damages from
Ship-borne Invasions
90% Intervals
Commercial fishing
Biofouling
Commercial
Biofouling
Sport fishing
Wildlife
Sport fishing
Wildlife watching
-500
0
500
1000
Difference
in Consumer
Surplus
(W/O-INV
million
2006$)
Millions
of Dollars
in Damages
(Consumer
Surplus
in 2006
$)
Conclusions on Economic
Impact
•Comprehensive estimates of invasion-induced
losses of ecosystem services from shipping
•Substantial reductions in sport and commercial
fishing
•Highly uncertain impacts on wildlife watching
•Impacts estimated conservatively:
•not including beach recreation, recreational
boating
•only US (not including Canada)
•only impacts in Great Lakes proper
Great Lakes as the Beachhead
Round goby
Spiny water-flea
Dave Jude. Center for Great Lakes Aquatic Sciences.
VHS
Zebra mussel
Spread of Mussels
1988
Spread of Mussels
1989
Spread of Mussels
1990
Spread of Mussels
1991
Spread of Mussels
1992
Spread of Mussels
1993
Spread of Mussels
1995
Spread of Mussels
2005
Spread of Mussels
2006
Lake Mead
Spread of Mussels
2008
Great Lakes as the Beachhead
Round goby
Spiny water-flea
Dave Jude. Center for Great Lakes Aquatic Sciences.
VHS
Zebra mussel
The Recreational Boating Network
Recreational boating nationwide
•$37 B/year Industry
•71 million participants in 2006
•18 million boats in use (large proportion in WI)
Our work on species spread by recreational boaters
•Surveys of boater behavior regarding boat hygiene
•Modeling of boater network (trips between lakes)
•Experiments on effectiveness and costs of different
interventions
WI Recreational Boater Network: Milfoil
Predicted
Risk
Estimated Risk
0.1%
1%
10%
Invaded =
Sources
Conclusions: Boater Network
•
Models have low ability to
predict which lakes will become
invaded
•
Containment more effective than
shielding at landscape scale
•
But what affects risk at
individual boater scale?
Different Methods of Intervention
Voluntary
Mandatory
Experiments on Different Methods
of Hand Removal and Boat Cleaning
.
Cost Effectiveness of
Intervention Strategies
Intervention
Implementation
Effectiveness
Cost/launch
Inspection &
hand removal
signage only
11%-79% Macrophytes
12%-63% Small
$200
Inspection &
hand removal
paid labor (peak
hrs) @ 7 weeks
4%-79% M
5%-70% S
$2,240
Inspection &
hand removal
paid labor full
time
(100%)(88%) =88% M
(100%)(70%)=70% S
$10,240
HP wash
containment
paid labor full
time
(100%)(88%)=88% M
(100%)(92%)=92% S
$15,000$20,000
HP wash
shield
paid labor full
time
88% M
92% S
$15,000$50,000
Conclusions for Experiments
.
1. High removal rates are possible, but appropriate
technique depends on organism type
•Visual inspection sufficient for macrophytes
•Power washing significantly better for small-bodied
organisms (e.g., plankton, seeds)
2. Voluntary interventions may be cost-effective but
compliance rates are not well documented.
3. Containment, rather than shielding, is a more-cost
effective intervention strategy.
Overall Conclusion
Most costeffective
regional
strategy would
be to contain
lakes that are
superspreaders:
•Heavily invaded
•Heavily visited
Notre Dame Env.
Research Center
Notre Dame Env.
Research Center
Future
Directions
Geographic analyses
combining ecology
and economics will
lead to more cost
effective
management.