Paper discussion on the invasive species challenge in estuarine and coastal environments by Mayra Sanchez

1. THE INVASIVE SPECIES CHALLENGE IN
ESTUARINE AND COASTAL
ENVIRONMENTS: MARRYING
MANAGEMENT AND SCIENCE
Susan L. Williams & Edwin D.
Grosholz
THE H.T. ODUM SYNTHESIS ESSAY
http://www.reefcorner.org
http://www.fishgame.com
http://www.reefcorner.org http://www.okeanosgroup.
com

2. INTRODUCTION
 Estuarine and costal environments are susceptible due to activities
relating
 Boating and shipping; Ballast water
 Aquarium trade
 Aquaculture
 Life seafood and bait
http://globallast.imo.org
 Despite public awareness and scientific interest on invasive species, research articles
are relatively few.

3. PROGRESS TOWARD MANAGEMENT: THE
REGULATORY FRAMEWORK
Leaders on regulatory framework:
Australia and New Zealand: proactive and integrated approach on the control of
invasive species.
 Centralized management efforts, strong science-based research and accessibility to
information are the key to effective control and eradication programs.
Slackers on regulatory framework:
USA lacks federal leadership and centralized management , there are laws that
overlap affecting the effectiveness of regulation and management and there is a slow
movement towards progress.
European Union uncoordinated as individual countries with different approach on
managing invasive species in the same water body

4. PROGRESS TOWARD MANAGEMENT: THE
REGULATORY FRAMEWORK
The existing legal instruments focus heavily on preventing introduction of
nonnative species, is undoubtedly the best way to reduce future costs of
management.
 Reasons why this legal instruments fail;
1. The introduction is no evident in its early stages
2. Understudies of economical impact reduces the allocation of resources
3. Externalities, which are the costs to society or native biota above
identifiable direct costs associated with the specific economy (aquaculture
products, eradication programs), are notoriously difficult to estimate,
particularly in the marine environment

5. WHY ALLOCATE PRECIOUS RESOURCES
TO INTRODUCED SPECIES IN THE
COASTAL ENVIRONMENT?
1) They are vectors for pathogens
2) Accumulate higher level of
contaminants than native species
3) Associated with endangering or
Phyllorhiza punctata
threatening native species Pomacanthus imperator
4) High economical impacts and
restoration
Penaeus monodon Pterois spp.
http://www.invasivespeciesinfo.gov/

6. SUCCESS IS POSSIBLE
Successes occurres when;
 introduced populations were small and restricted, human and financial resources
were available, and early action was taken.
Fall-back control program are successful when science and management
work together.
 Managers were in consensus that access to experts and basic biological and
ecological information was critical to managing the eradications and more was
desirable
 Managers also relied on scientists to provide eradication success/failure benchmarks
and reviews of programs to facilitate adaptive management
 Risk assessment and cost-benefit analyses were useful even if qualitative; the more
extensive the scientific evidence for the risk, the easier it was to take or defend
management actions.

7. TWO CASE STUDIES: THE INTRODUCTION
OF CAULERPA AND SPARTINA
Invasion of Caulerpa taxifolia
 Southern California
 US Noxious Weed List in 1999
 Identified invasion in 2000
 Eradicated in 2006, due to the Southern California Caulerpa Action Team
 No investigation before or during the eradication process.
http://www.hawaii.edu
 Australia
 Identified invasion 2000, eradication was not possible
 Control programs are a priority to limit dispersal
 This has given an opportunity to research management options and ecological effects of
introduced C. taxifolia

8. TWO CASE STUDIES: THE INTRODUCTION
OF CAULERPA AND SPARTINA
Invasion of Spartina spp.
Native to eastern North America
@World of Stock
 Introduced in 1890 in Washington (Accidental introduction)
 Total of 2,400ha 1997 to 90% reduction 2011 (USDA)
 Introduced in 1975 in California (Deliberated introduction by the Army Corps of Engineers)
 800ha 2005 to 80ha 2011 (San Francisco Bay eradication program)
 Some investigation was involved during the
eradication program, which demonstrate the
capacity of management and science to achieve
similar goals without conflict
@World of Stock

9. AGENDA FOR MANAGEMENT-FOCUSED
RESEARCH
 Effects in Communities and Ecosystems: More focus on ecosystem
processes and function instead of the typical approach.
 Prevention:
 Trait base approach: using previous invasion to detect future problems.
 Species distribution modeling: model that relates species distribution data
with information on the environmental and/or spatial characteristics of those
locations
 Early Detection

10.  Risk Assessment: determines the probability of a species to established and cause
harm. Help prioritize and initiate action.
In absence of effective prevention and early detection
 Understanding Connectivity to Prioritize Eradication and Control Efforts: There is a
lack of understanding connectivity among population of marine species. More
advanced knowledge will help prioritize on eradication and control.
 Eradication and Control : There is a need for tested techniques of eradication and
control
 Bio-controls
 Transgenic approach to control reproduction
 Pheromone control
 Disruption of molting*

11.  Need for Decision Support : There is a need for a single source, readily
accessible, step-wise management decision support system.
 Australia’s National Introduced Marine Pest Information System central repository of
information on the biology, ecology and distribution (international and national) of invasive
marine pest species
 USA National Invasive Species Information Center (NISIC): Gateway to invasive species
information
 Evolutionary Potential: Poorly investigated how short term or rapid evolution
influences the success or failure of introduced species
 Ecological Economics and Introduced Species Cross-disciplinary: Relates to the
risk assessment involving cost of introduced species and the development of
better management recommendations

12. Overlooked research needs:
 Facilitation of Subsequent Introduced Species : How can introduced species
become facilitators for other invasive species.
 Climate Change and Specie Introduction:
 There is a need for understanding how climate change interacts with coastal
invasions:
 Rise SST
 Rise Sea Level
 Rise CO2
 Ocean Acidification

13. DISCUSSION
 Management of introduced species requires the same will and resources
that nations have applied to reducing pollution and restoring wetlands
and fisheries stocks, with high pay-offs, and investments spent on
restoration efforts risk being obliterated by the introduction of just one
successful nonnative species.