The Nero dilemma in The Nero dilemma in invasion biologyinvasion biology

Francesca Gherardi, University of Florence Francesca Gherardi, University of Florence (Italy)(Italy)

The Nero dilemmaThe Nero dilemma

In history In history

and scienceand science

The great fire of RomeThe great fire of Rome

In 64 AD, two In 64 AD, two thirds of Rome thirds of Rome had been had been destroyed by a destroyed by a fire. fire.

Ten of Rome's Ten of Rome's fourteen districts fourteen districts were in ruin. were in ruin.

The guilt of NeroThe guilt of Nero

The Emperor Nero Claudius The Emperor Nero Claudius Caesar (37-68) was blamed Caesar (37-68) was blamed for the disaster. for the disaster.

The aristocrat and historian The aristocrat and historian Tacitus claimed that Nero Tacitus claimed that Nero watched Rome burn while watched Rome burn while playing his lyre on the playing his lyre on the summit of the Palatine. summit of the Palatine.

The Nero dilemma in conservation The Nero dilemma in conservation biologybiology

When confronted with the When confronted with the current disintegration of the current disintegration of the “natural world”, there are “natural world”, there are severe penalties for “fiddling” severe penalties for “fiddling” with ideas for as long as one with ideas for as long as one likes –or until Rome is in likes –or until Rome is in ashes. The risks of non-action ashes. The risks of non-action may be greater than the risks may be greater than the risks of inappropriate actions. of inappropriate actions. Rather, the “best” hypothesis Rather, the “best” hypothesis must be chosen and must be chosen and implemented (implemented (Soulé 1986).

BioinvasionsBioinvasions

““We must make no mistake: We must make no mistake: we are seeing one of the great we are seeing one of the great historical convulsions in the historical convulsions in the world’s fauna and flora.”world’s fauna and flora.” Elton 1958Elton 1958

A “historical convulsion” made of A “historical convulsion” made of over 480,000 alien speciesover 480,000 alien species

25,000/42,000

26,000/27,515

1952/20,000 8750/24,00018,000/45,000

11,605/55,000

20/346 17/54 20/296 16/247 30/316 25/428

97/650 47/542 70/850 8/725 4/1221 3/1635

53/247 48/80 20/700 24/394 NA/741 NA/985

138/938 12/54 29/216 20/220 300/2546 76/3000

4500/650,000 1000/24,700 150/85,920 NA/86,000 1100/54,430 NA/1,000,000

<5% 5-25% 25-50% 50-75% >75%

1. Plants; 2. Mammals; 3. Birds; 4. Reptiles & amphibians; 5. Fish; 6. Arthropods

1

2

3

4

5

6

USA UK AUS ZA IND BR

Pimentel 2002Pimentel 2002

Bioinvasions are carriers of huge Bioinvasions are carriers of huge damagesdamages

Invasive alien species Invasive alien species are “one of the most are “one of the most serious ecological and serious ecological and economic threats of the economic threats of the new millennium” (Cox new millennium” (Cox 2004). 2004).

National Geographic

Ecological damagesEcological damages

Their impact on global biodiversity is second Their impact on global biodiversity is second only to habitat destruction (Walker & Steffen only to habitat destruction (Walker & Steffen 1997). 1997). Over the last 500 years, they have come Over the last 500 years, they have come to dominate 3% of the Earth’s ice-free surface to dominate 3% of the Earth’s ice-free surface (Mack 1985). (Mack 1985). They may lead to a homogenization of the They may lead to a homogenization of the biosphere biosphere (Lodge 1993) (Lodge 1993) and to the creation of a and to the creation of a “New Pangea” (Rosenzweig 2001).“New Pangea” (Rosenzweig 2001).

Economic damagesEconomic damages

In the U.S., direct economic damages associated In the U.S., direct economic damages associated with alien invasive species effects and their with alien invasive species effects and their control amount to approximately $120 control amount to approximately $120 billion/year ($ 122,639 million per year) billion/year ($ 122,639 million per year) (Pimentel et al. 2004).(Pimentel et al. 2004).

Damages to the health of humans Damages to the health of humans and of the species useful to manand of the species useful to man

Newly introduced species often act Newly introduced species often act as vectors of disease. as vectors of disease. In the U.S., the Asian tiger In the U.S., the Asian tiger mosquito (mosquito (Aedes albopictusAedes albopictus) is a ) is a vector of dengue fever, other vector of dengue fever, other human arboviruses, and eastern human arboviruses, and eastern equine encephalitis (Craig 1993).equine encephalitis (Craig 1993).

Land-use change, Disturbance, Habitat

fragmentation

CLIMATE CHANGE AN

TH

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CHANCE FOR NEW INVASIONS PREVALENCE OF INVADERS

BIODIVERSITY & ECOSYSTEM FUNCTIONING

ECOSYSTEM GOODS & SERVICES

HUMAN HEALTH WELL-BEING

But bioinvasions may also affect But bioinvasions may also affect the history and the politics !!!the history and the politics !!!

A strain of the blight fungus (A strain of the blight fungus (Phytophtora Phytophtora infestansinfestans) reached western Europe in the 1840s ) reached western Europe in the 1840s where it decimated potato crops. where it decimated potato crops.

The almost total loss of the potato crop led to The almost total loss of the potato crop led to the the Great FamineGreat Famine (1845-1849) in Ireland, in (1845-1849) in Ireland, in which 1.5 million people died and many more which 1.5 million people died and many more were forced to emigrate, mostly to the U.S. [One were forced to emigrate, mostly to the U.S. [One of them was the grand-grandfather of JFK.]of them was the grand-grandfather of JFK.]

A role for researchersA role for researchers

““The need for more research should not The need for more research should not be casually invoked as an excuse for be casually invoked as an excuse for inaction.”inaction.”Simberloff 2003Simberloff 2003

Six points of discussionSix points of discussion

Defining NIS, Judging NIS, Assessing the Defining NIS, Judging NIS, Assessing the impact of IAS, Predicting IAS, Preventing impact of IAS, Predicting IAS, Preventing IAS, Managing IAS IAS, Managing IAS

Point 1: DEFINING NISPoint 1: DEFINING NISPoint 1: DEFINING NISPoint 1: DEFINING NIS

““It is often vagueness It is often vagueness in definitions that in definitions that makes it difficult to makes it difficult to determine the where, determine the where, how, and who of how, and who of conservation conservation strategies.”strategies.”

McShane 2003McShane 2003

Labels in the literatureLabels in the literature

adventive adventive (Walker 1989)(Walker 1989)alien alien (Crawley et al. 1996) (Crawley et al. 1996) allochthonous allochthonous (Allaby 1994)(Allaby 1994)exotic exotic (Green 1997)(Green 1997)invasive invasive (Daehler 1998)(Daehler 1998)naturalized naturalized (Walker 1989)(Walker 1989)neozoanneozoannonnative nonnative (Davis et al. 2000)(Davis et al. 2000)nonindigenous nonindigenous (Pimentel et al. 2000)(Pimentel et al. 2000)and:and: colonizer colonizer (Williamson 1996),(Williamson 1996), immigrant immigrant (Bazzaz (Bazzaz 1986), 1986), importedimported (Williamson & Fitter 1996), (Williamson & Fitter 1996), introduced introduced (Lonsdale(Lonsdale 1994), 1994), pestpest, , weedy weedy (Fox 1990), (Fox 1990), etc.etc.

Glossary from Kolar & Lodge Glossary from Kolar & Lodge (2001): (2001): the voice of sciencethe voice of science

NONINDIGENOUS SPECIES: a species introduced to areas beyond its native range by human activity.INVASIVE SPECIES: a nonindigenous species that spreads from the point of introduction and becomes abundant.

NONINDIGENOUS SPECIES: a species introduced to areas beyond its native range by human activity.INVASIVE SPECIES: a nonindigenous species that spreads from the point of introduction and becomes abundant.

ALIEN SPECIES (nonnative, nonindigenous, foreign, exotic): a species, subspecies, or lower taxon occurring outside of its natural range (past and present) and dispersal potential (i.e. outside the range it occupies naturally or could not occupy without direct or indirect introduction or care by humans) …INVASIVE ALIEN SPECIES: an alien species which becomes established in natural or semi-natural ecosystems or habitat, is an agent of change, and threatens native biological diversity.

ALIEN SPECIES (nonnative, nonindigenous, foreign, exotic): a species, subspecies, or lower taxon occurring outside of its natural range (past and present) and dispersal potential (i.e. outside the range it occupies naturally or could not occupy without direct or indirect introduction or care by humans) …INVASIVE ALIEN SPECIES: an alien species which becomes established in natural or semi-natural ecosystems or habitat, is an agent of change, and threatens native biological diversity.

Glossary from IUCN (2002): Glossary from IUCN (2002): the voice of international the voice of international organizationsorganizations

Glossary from the Executive Order Glossary from the Executive Order 1311213112 (1999): the voice of (1999): the voice of governmentsgovernments

ALIEN SPECIES: any species, including its seeds, eggs, spores, or other biological material capable of propagating that species, that is not native to that ecosystem. INVASIVE SPECIES: an alien species whose introduction does or is likely to cause economic or environmental harm or harm to human health.

ALIEN SPECIES: any species, including its seeds, eggs, spores, or other biological material capable of propagating that species, that is not native to that ecosystem. INVASIVE SPECIES: an alien species whose introduction does or is likely to cause economic or environmental harm or harm to human health.

Austropotamobius pallipesAustropotamobius pallipes: : nonindigenous species to Ireland nonindigenous species to Ireland and Spain?and Spain?

Austropotamobius pallipesAustropotamobius pallipes is a crayfish of is a crayfish of conservation concern.conservation concern.

DNA-mitochondrial analysis: Irish populations belong to the same aplotype as some French populations (introduction by French monks in XII century?) and the Spanish populations as Tuscan populations (introduction during the Renaissance?).

Point 2: JUDGING NISPoint 2: JUDGING NISPoint 2: JUDGING NISPoint 2: JUDGING NIS

““Any characterization Any characterization that any or all that any or all indigenous species are indigenous species are good or bad is a value good or bad is a value judgment, not judgment, not science.”science.”

Rosenzweig 2001Rosenzweig 2001

From the side of invasion biologists: From the side of invasion biologists: judgments behind the several judgments behind the several terms used terms used ““agents of extinctions” (Lodge & Hill 1994) agents of extinctions” (Lodge & Hill 1994) “ “components of global environmental changes” components of global environmental changes” (Williamson & Fitter 1996) -perhaps even more (Williamson & Fitter 1996) -perhaps even more significant than global warming (Daehler & significant than global warming (Daehler & Gordon 1997) Gordon 1997) causes of the “homogenization” (Lodge 1993) causes of the “homogenization” (Lodge 1993) or “Mcdonaldization” of the biosphere (Lövei or “Mcdonaldization” of the biosphere (Lövei 1997)1997) catalysts of global “McEcosystems” (Enserink catalysts of global “McEcosystems” (Enserink 1999)1999), , where most species –losers- will be where most species –losers- will be replaced by a few winners (McKinney & replaced by a few winners (McKinney & Lockwood 1999)Lockwood 1999) “ “ecological malignancies” (Gherardi 2000) ecological malignancies” (Gherardi 2000)

From the side of their accusers: From the side of their accusers: a pseudo-sciencea pseudo-science

Theodoropoulos 2003: Theodoropoulos 2003:

““Empirical data do not support either the Empirical data do not support either the hypotheses or conclusions of invasion biology, hypotheses or conclusions of invasion biology, that its that its fundamental concepts are fundamental concepts are nonoperational and subjectivenonoperational and subjective, and that , and that the the information-pool is strongly biasedinformation-pool is strongly biased. This lack of . This lack of adherence to sound scientific practices and the adherence to sound scientific practices and the repeated deliberate distorsionsrepeated deliberate distorsions and and fabrications fabrications of evidenceof evidence, demonstrate that invasion biology , demonstrate that invasion biology is a pseudoscience.”is a pseudoscience.”

From (cont.): From (cont.): xenophobiaxenophobia

Subramaniam (2001): Subramaniam (2001):

“… “… we are living in a cultural moment where we are living in a cultural moment where the anxieties of globalization are feeding the anxieties of globalization are feeding nationalisms through xenophobia. nationalisms through xenophobia. The battle The battle against exotic and alien plants is a symptom of against exotic and alien plants is a symptom of a campaign that misplaces and displaces a campaign that misplaces and displaces anxieties about economic, social, political, and anxieties about economic, social, political, and cultural changes onto outsiders and cultural changes onto outsiders and foreigners.”foreigners.”

If we look at a market …If we look at a market …

… … we agree with Ewel et al. (1999) we agree with Ewel et al. (1999)

Humans depend heavily on non-native organisms for Humans depend heavily on non-native organisms for food, shelter, medicine, ecosystem services, aesthetic food, shelter, medicine, ecosystem services, aesthetic enjoyment, and cultural identity. enjoyment, and cultural identity. Over 70% of the world’s food comes from just nine Over 70% of the world’s food comes from just nine crops (wheat, maize, rice, potato, barley, cassava, crops (wheat, maize, rice, potato, barley, cassava, soybean, sugar cane, and oats), each of which is soybean, sugar cane, and oats), each of which is cultivated far beyond its natural range.cultivated far beyond its natural range.Similarly, 85% of industrial forestry plantations are Similarly, 85% of industrial forestry plantations are established with species of just three genera established with species of just three genera (Eucalyptus, Pinus, and Tectona), which are also (Eucalyptus, Pinus, and Tectona), which are also largely cultivated as exotics.largely cultivated as exotics.Although native organisms fulfill some human Although native organisms fulfill some human requirements, nonnative organisms play an integral requirements, nonnative organisms play an integral role in the economies and cultures of all regionsrole in the economies and cultures of all regions..

The wise position: Daniel Simberloff The wise position: Daniel Simberloff (2003) (2003)

I believe that I believe that the strongest ethical basesthe strongest ethical bases, and , and possibly the only ethical bases, possibly the only ethical bases, for concern for concern about introduced speciesabout introduced species are that they can are that they can threaten the existence of native species and threaten the existence of native species and communities communities and that they can cause and that they can cause staggering damage, reflected in economic staggering damage, reflected in economic terms, to human endeavors. terms, to human endeavors.

Point 3: ASSESSING THE Point 3: ASSESSING THE IMPACT OF NISIMPACT OF NISPoint 3: ASSESSING THE Point 3: ASSESSING THE IMPACT OF NISIMPACT OF NIS

““Much of the Much of the discussion of discussion of ecological effects of ecological effects of invaders has been invaders has been purely anecdotal in purely anecdotal in nature.”nature.”

Parker et al. 1999Parker et al. 1999

The common knowledgeThe common knowledge

IAS: IAS: alter and disrupt the biotic structure of land, alter and disrupt the biotic structure of land, freshwater, and marine ecosystems freshwater, and marine ecosystems affect the wellbeing of other species through affect the wellbeing of other species through competition, amensalism or swamping competition, amensalism or swamping push many species towards extinction push many species towards extinction reduce the productivity of agriculture and reduce the productivity of agriculture and aquaculture aquaculture pose threats to the health of humans and of pose threats to the health of humans and of plant and animals useful to manplant and animals useful to man

Studies on impact: a few and Studies on impact: a few and unequally distributed per biological unequally distributed per biological levellevel

Biological Abstracts, Biosis, ASFA (1980-1997)

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Freshw fish Freshw invert Marine invert Terrestr invert

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Parker et al. 1999Parker et al. 1999

Studies on impact: mostly dealing Studies on impact: mostly dealing with a few paradigmatic specieswith a few paradigmatic species

Ricciardi 2005

1980 1985 1990 1995 2000 20050

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Effects on Effects on communities/ecosystemscommunities/ecosystems

Nile perch in Lake Victoria: foodweb Nile perch in Lake Victoria: foodweb simplificationsimplification

African fisheagles

KingfishersCormorants

MANSandmartins

Haplochromines

Non -cichlids

Haplochromines

Non -cichlids

Haplochromines

dagaa

Haplochromines

Non -cichlids

HaplochrominesZooplankton MolluscsLakefliesTilapias

Plankton / detritus

African fisheagles

KingfishersCormorants

MANSandmartins

Nile perch

DagaaSmall Nile perch

Zooplankton CaridinaLakefliesNile tilapia

Plankton / detritus

beforebefore

afterafter

Zebra mussels as ecosystem engineers

Competes with unionids

Increases bottomroughness and

hardness

Increases sedimentation-rate

Alters sediment composition (fine)

Increases water clarity

Alters N and P cycling

Decreases suspended solids

Increases macrophyte coverage and depth

Increases periphyton production

Changes pelagic community

Increases bottom-feeding fish abundance

Changes composition and abundance of

plankton

Changes benthic community

Effects on native speciesEffects on native species

One of the leading causes of species One of the leading causes of species extinction, extirpation or extinction, extirpation or endangermentendangerment

Mechanisms leading to species extinction, Mechanisms leading to species extinction, extirpation or endangerment are (Mack et al. extirpation or endangerment are (Mack et al. 2000):2000): Parasitism Parasitism Transmission of parasites Transmission of parasites PredationPredation Competition for resources Competition for resources Interference competition Interference competition HybridizationHybridization

The “dirty dozen”: nonindigenous The “dirty dozen”: nonindigenous crayfishcrayfish

predationpredation disease disease transmissiontransmission

hybridizationhybridization

competitioncompetition

Factors responsible for threatening Factors responsible for threatening species (in the U.S.; Wilcove et al. species (in the U.S.; Wilcove et al. 1998)1998)

% of species affected by each factor

Habitat Pollution Over- IAS Diseasedegradation exploitation

Threatened species group and loss

All species (1880 species) 85 24 17 49 (II) 3

All vertebrates (494 species) 92 46 27 47 (II) 8Mammals ( 85 species) 89 19 47 27 (III) 8Birds (98 species) 90 22 33 69 (II) 37Amphibians (60 species) 87 47 17 27 (III) 0Fishes (213 species) 97 90 15 17 (III) 0

All invertebrates (331 species) 87 45 23 27 (III) 0Freshwater mussels (102 species) 97 90 15 17 (III) 0Butterflies (33 species) 97 24 30 36 (II) 0

Plants (1055 species) 81 7 10 57 (II) 1

Species may be affected by more than one factor; therefore, rows do not sum to 100%.

Density of native unionid mussels and zebra mussels in Lake St. Clair

Nalepa et al. (2001)

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Year

Scapegoats of other anthropogenic Scapegoats of other anthropogenic effects on ecosystems?effects on ecosystems?

Gurevitch & Padilla (2004):Gurevitch & Padilla (2004):

Native species decline often occurs Native species decline often occurs simultaneously and in the same place as simultaneously and in the same place as invasion by non-native speciesinvasion by non-native species, leading many , leading many conservationists and researchers to believe conservationists and researchers to believe that invasions and extinctions are closely that invasions and extinctions are closely linked. linked.

Correlation is too often assumed to imply Correlation is too often assumed to imply causationcausation. .

The intervention of other causes: The intervention of other causes: the extirpation of cichlids in Lake the extirpation of cichlids in Lake VictoriaVictoria

The Nile perch, introduced in the early 1960s, The Nile perch, introduced in the early 1960s, is accused to have led to the extinction more is accused to have led to the extinction more than 200 of the 300-500 endemic cichlid than 200 of the 300-500 endemic cichlid species (e.g. Goldschmidt 1996).species (e.g. Goldschmidt 1996).

But:But:

The decline started in the 1920s with the development The decline started in the 1920s with the development of railroads, erosion, and shoreline destruction of railroads, erosion, and shoreline destruction (Verschuren et al. 2002).(Verschuren et al. 2002).

Urbanization in the 1970s increased eutrophication Urbanization in the 1970s increased eutrophication and decreased lake transparency (Aloo 2003) and decreased lake transparency (Aloo 2003) affecting sexual selection (Seehausen et al. 2003).affecting sexual selection (Seehausen et al. 2003).

Increased nutrients led to anoxic events.Increased nutrients led to anoxic events. Increased nutrients favored the invader water Increased nutrients favored the invader water

hyacinth that has altered nursery areas for fishes hyacinth that has altered nursery areas for fishes (Witte et al. 2000), including the Nile perch.(Witte et al. 2000), including the Nile perch.

Difficulties in disentangling Difficulties in disentangling proximate and ultimate causes of proximate and ultimate causes of declinedecline

Exotic species might be Exotic species might be

a primary cause for decline, a primary cause for decline,

a contributing factor for a species already in serious trouble, a contributing factor for a species already in serious trouble,

the final nail in the coffin or the final nail in the coffin or

merely the bouquet at the funeralmerely the bouquet at the funeral..

Gurevitch & Padilla 2004 Gurevitch & Padilla 2004

Beneath the tip of the iceberg Beneath the tip of the iceberg

Rapid evolutionary changesRapid evolutionary changes

A human-mediated evolutionary A human-mediated evolutionary revolution (Cox 2004)revolution (Cox 2004)

Once established, IAS: Once established, IAS:

are freed from the constraints are freed from the constraints of gene flow from their parent of gene flow from their parent population;population;

are freed from biotic are freed from biotic pressures of former enemies; pressures of former enemies;

are subject to altered are subject to altered selection pressures; selection pressures;

impose strong new impose strong new evolutionary pressures on the evolutionary pressures on the natives; natives;

may hybridize with close may hybridize with close indigenous relatives. indigenous relatives.

Spartina anglicaSpartina anglica: : hybridization leading to hybridization leading to invasioninvasion

Hybridization at invasion: Hybridization at invasion: contamination of native genotypes contamination of native genotypes

Mallards Mallards Anas platyrhynchosAnas platyrhynchos and and A. A. superliciosasuperliciosa (in Australia and New Zealand) (in Australia and New Zealand) (Gillepsie 1985).(Gillepsie 1985). Ruddy duck, Ruddy duck, Oxyura jamaicensisOxyura jamaicensis, and white-, and white-headed duck, headed duck, O. leucocephalaO. leucocephala (in Europe) (in Europe) (Holmes 1994).(Holmes 1994).

Hybridization at invasion (cont.)Hybridization at invasion (cont.)

MosquitofishesMosquitofishes Gambusia affinis Gambusia affinis and and G. G. heterochirheterochir (in North America) (Courtney & (in North America) (Courtney & Meffe 1989).Meffe 1989).

Salmonids, tilapia, sunfish (Hindar et al. Salmonids, tilapia, sunfish (Hindar et al. 1991): some artificial. 1991): some artificial.

Carassius auratusCarassius auratus and and C. carassiusC. carassius in UK in UK (H(Hänfling et al. 2005).änfling et al. 2005).

Hybridization at invasion (cont.)Hybridization at invasion (cont.)

Daphnia galeataDaphnia galeata in Ontario and NY hybrids of in Ontario and NY hybrids of North American and European populations (Taylor North American and European populations (Taylor & Hebert 1993).& Hebert 1993).

Orconectes rusticusOrconectes rusticus and and O. propinquusO. propinquus in in Wisconsin (from matings of Wisconsin (from matings of rusticusrusticus females and females and propinquuspropinquus males: fecund and competitive) males: fecund and competitive) (Perry et al. 2001). (Perry et al. 2001).

The experts’ opinion: Harold The experts’ opinion: Harold Mooney & Elsa Cleland (2001)Mooney & Elsa Cleland (2001)

We are now developing a whole new We are now developing a whole new cosmopolitan assemblage of organisms across cosmopolitan assemblage of organisms across the surface of the Earth the surface of the Earth with large with large consequences consequences not only for the functioning of not only for the functioning of ecosystems but also ecosystems but also for the future evolutionary for the future evolutionary trajectory of lifetrajectory of life..

Effects on economies Effects on economies

IAS are externalities IAS are externalities (Perrings et (Perrings et al. 2000)al. 2000)

They are They are externalitiesexternalities –costs which a given activity –costs which a given activity unintentionally imposes on another, without the unintentionally imposes on another, without the latter being able to exact a compensation for the latter being able to exact a compensation for the damage received.damage received.

External effects implies that, in order to persist, the External effects implies that, in order to persist, the damage must be associated with a continuing flow damage must be associated with a continuing flow of output from the source. of output from the source.

Bioinvasions, on the other hand, Bioinvasions, on the other hand, once set in motion once set in motion are largely self-perpetuating. Even if the source of are largely self-perpetuating. Even if the source of the introduction ceases its activity, damages from the introduction ceases its activity, damages from the invasives continue and often increase over the invasives continue and often increase over time.time.

Monetary costs for IAS (estimated per Monetary costs for IAS (estimated per year in the US: 120,105 millions $) year in the US: 120,105 millions $)

Category Nonindigenous Losses Control Totalspecies and damages costs

PLANTS 25,000 Aquatic weeds 10 100 110

FISH 138 5400 NA 5400

ARTHROPODS 4500 Green crab 44 NA 44

MOLLUSKS 88 Zebra mussel --- --- 1000 Asian clam 1000 NA 1000

LIVESTOCK DISEASES 14,000 NA 14,000

HUMAN DISEASES NA 7500 7500

Annual costs per millions of dollars in the US (Pimentel et al. 2004)Annual costs per millions of dollars in the US (Pimentel et al. 2004)

Costs associated with biodiversity Costs associated with biodiversity loss: the Flathead catchment loss: the Flathead catchment (Montana)(Montana)“A tiny shrimp had starved eagles out of the sky”“A tiny shrimp had starved eagles out of the sky”

Daphnia longiremisLeptodora kindtii

kokanee

Tourists

from 46,500 to 1000 in 6 years with a loss of 5 million $

from 120,000 to 50 in 10 years

bald eagle, gulls, ducks

grizzly bear, coyote, mink, otter

Mysis relicta

1981

Revenues from IAS in Lake Victoria Revenues from IAS in Lake Victoria after the introduction of the Nile perch after the introduction of the Nile perch (1962: official British stocking (1962: official British stocking program)program)

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Lake Victoria export market trendsLake Victoria export market trends

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Pros of the Nile perch during 1975-Pros of the Nile perch during 1975-19891989

The production gains amounted to about The production gains amounted to about US$280 million. US$280 million.

The number of fishers and their dependents The number of fishers and their dependents increased of 267 percent. increased of 267 percent. 1.2 million people 1.2 million people depends entirely on fishery.depends entirely on fishery.

The increase of fish production meant that The increase of fish production meant that greater numbers of people were able to eat greater numbers of people were able to eat high-quality animal proteins. high-quality animal proteins.

The export of the perch provided a new source The export of the perch provided a new source of foreign exchange. About 5-10% of of foreign exchange. About 5-10% of production is for export.production is for export.

Cons of the Nile perch (Kasulo Cons of the Nile perch (Kasulo 2000)2000)

Increased cost of boats and nets is a barrier to ownership in the sector.

Income is concentrated in the hands of a small minority of fishers.

Scarce consumption by the locals: people fear that eating this cannibalistic fish could spread cannibalism among humans (T. Goldschmidt, pers. comm.).

The balance between ecology The balance between ecology and economics is very weakand economics is very weak

Politics

Employment

Profit

Socio-cultural issues

Biodiversity Gene pool

Ecosystem dynamics

Environmental protection

ECOLOGYECOLOGY ECONOMICSECONOMICS

Point 4: PREDICTING IASPoint 4: PREDICTING IASPoint 4: PREDICTING IASPoint 4: PREDICTING IAS

Predicting potential invaders: a Predicting potential invaders: a priority for invasion biologists priority for invasion biologists (Mack et al. 2000)(Mack et al. 2000)

Learning to identify invaders in advanceLearning to identify invaders in advance would would tell us a great deal about how life history traits tell us a great deal about how life history traits evolve and how biotic communities are evolve and how biotic communities are assembled. assembled.

In practical terms, it In practical terms, it could reveal the most could reveal the most effective means to prevent future invasions.effective means to prevent future invasions.

Published articles about Published articles about “predictions” (Kolar & Lodge 2001)“predictions” (Kolar & Lodge 2001)

Biological Abstracts (1986-1999)

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(1) Can we predict the (1) Can we predict the number of introduced number of introduced species?species?

The knowledge of the past helpsThe knowledge of the past helps

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626 events of introduction and translocation, involving 626 events of introduction and translocation, involving 166 species, mostly: 19 salmonids; 54 cyprinids; 14 166 species, mostly: 19 salmonids; 54 cyprinids; 14 ictalurids; 12 coregonids (Cowx 2005).ictalurids; 12 coregonids (Cowx 2005).

The history of fish introduction in EuropeThe history of fish introduction in Europe

The knowledge of the present helpsThe knowledge of the present helps

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FAO Database on Introductions of Aquatic SpeciesFAO Database on Introductions of Aquatic Species

Alien species in inland watersAlien species in inland waters

The future: introductions are The future: introductions are destined to increasedestined to increase

Growth in the volume and complexity of international Growth in the volume and complexity of international trade trade has increased the frequency of introductions along has increased the frequency of introductions along existing pathways, the number of new pathways, and the existing pathways, the number of new pathways, and the ease with which potentially invasive species can move ease with which potentially invasive species can move along those pathways. along those pathways.

The deregulation of national and international marketsThe deregulation of national and international markets has reduced both the barriers to trade and the has reduced both the barriers to trade and the surveillance of trade, thereby increasing the risks of surveillance of trade, thereby increasing the risks of invasions. invasions.

Human behavior, social norms, and cultural traditionsHuman behavior, social norms, and cultural traditions have adapted only slowly to the new risks, and this, in have adapted only slowly to the new risks, and this, in turn, has increased the impacts of invasions. turn, has increased the impacts of invasions.

(2) Can we predict the (2) Can we predict the relative number of invaders? relative number of invaders?

Transitions from transport Transitions from transport pathways to invasivenesspathways to invasiveness

Species entrained in transport Species entrained in transport pathway pathway

Survives transport and Survives transport and introductionintroduction

EstablishmentEstablishment

NoninvasiveNoninvasive

InvasiveInvasive

SSpprreeaadd

Fails in Fails in transporttransport

Fails toFails toestablishestablish

Kolar & Lodge 2001Kolar & Lodge 2001

The tens ruleThe tens rule

10% (5-20%) of introduced species become established, 10% (5-20%) of introduced species become established, and 10% (5-20%) of those established become pests and 10% (5-20%) of those established become pests (Williamson 1996). (Williamson 1996).

British angiosperms

Australian pasture plants

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0 10 20 30 40 50 60 70 80 90 100

% success

Escaping Establishing Becoming a pest

British PinaceaeBritish edible crops

US high impactHawaiian birds

Biocontrol insectsby target

Canadian biocontrolIsland mammals

Australian pasture plants

British angiosperms

The tens rule revisitedThe tens rule revisited

0

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0 10 20 30 40 50 60 70 80 90 100

% success

Establishing Spreading

PlanariansInsects

Island mammalsAustralian mammals

Island birdsContinental birds

World parrotsE, NA vertebrates

British animalsAustrian animalsGerman animals

Establishment and spreading success far exceed 10% Establishment and spreading success far exceed 10% in several taxa (Jeschke & Strayer 2005) in several taxa (Jeschke & Strayer 2005)

(3) Can we predict vectors, (3) Can we predict vectors, sources, and pathways?sources, and pathways?

VectorsVectors

(1) Ballast (both solid ballast and ballast water)(1) Ballast (both solid ballast and ballast water)

(2) Canal building providing corridors for rapid (2) Canal building providing corridors for rapid dispersal of aquatic organisms (e.g. the Welland dispersal of aquatic organisms (e.g. the Welland Canal, Suez Canal)Canal, Suez Canal)

(3) Fouled ship hulls (also of recreational boats) (3) Fouled ship hulls (also of recreational boats)

(4) Deliberate introductions of “desirable” species (4) Deliberate introductions of “desirable” species (for: agriculture/aquaculture, restocking, biocontrol (for: agriculture/aquaculture, restocking, biocontrol or research)or research)

(5) Deliberate releases of organisms not intended to (5) Deliberate releases of organisms not intended to form sustaining populations (unwanted pets: 65% of form sustaining populations (unwanted pets: 65% of alien fish in the US from aquarium trade; baits; alien fish in the US from aquarium trade; baits; parasites and disease agents from desirable parasites and disease agents from desirable species)species)

(6) Inadvertent release of organisms (escapes from (6) Inadvertent release of organisms (escapes from aquaculture or agriculture, contaminants of aquaculture or agriculture, contaminants of deliberate release) deliberate release)

(7) The Internet trade(7) The Internet trade

Involuntarily introductions: the Involuntarily introductions: the problem of ballast watersproblem of ballast waters

Ballast water transported by cargo Ballast water transported by cargo vessels: 3-12 billion tones per year. vessels: 3-12 billion tones per year.

35,000 merchant vessels at sea 35,000 merchant vessels at sea (meta-current) transporting more (meta-current) transporting more than 7000 species per hour.than 7000 species per hour.

Adding all kinds of vessels: Adding all kinds of vessels: 10,000 10,000 species transported per hourspecies transported per hour (Carlton 1999).(Carlton 1999).

Involuntarily introductions: CanalsInvoluntarily introductions: Canals

Invasion corridors Invasion corridors for the transfer of for the transfer of Ponto-Caspian taxa Ponto-Caspian taxa to the Baltic and to the Baltic and North seas, and to North seas, and to the Laurentian the Laurentian Great Lakes: Great Lakes: natural or human-natural or human-vectored diffusion vectored diffusion followed by a jump followed by a jump dispersal in ships’ dispersal in ships’ ballast.ballast.

Caspian Sea

Black Sea

North Sea

Baltic Sea

Bizarre ways of involuntarily Bizarre ways of involuntarily introductions: Asian tiger introductions: Asian tiger mosquitoesmosquitoes

Through the trade of Through the trade of used tires (used to make used tires (used to make recycled rubber products recycled rubber products or asphalt, as fuel for or asphalt, as fuel for power plants, etc.).power plants, etc.).

Bizarre ways of voluntarily Bizarre ways of voluntarily introductions: The gypsy moth, introductions: The gypsy moth, Lymantria disparLymantria dispar

One of North America's most devastating One of North America's most devastating forest pests, it was introduced from France in forest pests, it was introduced from France in 1868-69 in Boston by a “bizarre” artist (E. 1868-69 in Boston by a “bizarre” artist (E. Leopold Trouvelot) for silk production.Leopold Trouvelot) for silk production.

““Massive” voluntarily introductions: Massive” voluntarily introductions: Acclimatization societiesAcclimatization societies

Establishment of Establishment of Acclimatization Societies Acclimatization Societies between 1543 (Garden in Pisa, between 1543 (Garden in Pisa, Italy) and 1930 (the Hawaiian Italy) and 1930 (the Hawaiian acclimatization society), mostly acclimatization society), mostly in the second half of 1800. in the second half of 1800. Moved hundreds of plants and Moved hundreds of plants and animals between North animals between North America, Europe, East Asia, and America, Europe, East Asia, and European countries. Aim: the European countries. Aim: the reconstitution of non-European reconstitution of non-European landscapes as a whole. landscapes as a whole.

(4) Can we predict the whys (4) Can we predict the whys of an invader’s of an invader’s establishment?establishment?

The propagule (or invasion) The propagule (or invasion) pressurepressure

Invasion success increases with the number of Invasion success increases with the number of propagules present in an inoculum and with the propagules present in an inoculum and with the number of inocula.number of inocula.

Dawson 1984Dawson 1984

0

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2 3-10 11-50 51-200 201-500 501-1000 >1000

Number introduced

Succ

ess

(%)

The time lag effect as a The time lag effect as a confounding variableconfounding variable

Introduced species may stay at a low population size for Introduced species may stay at a low population size for years (0 for zebra mussels, 80 for the fungus years (0 for zebra mussels, 80 for the fungus Entomophaga maimaigaEntomophaga maimaiga) and then explode at some later ) and then explode at some later date usually following a logistic pattern of growth (due date usually following a logistic pattern of growth (due to: limits on the detection ability, normal population to: limits on the detection ability, normal population growth lag phase, environmental change, genetic growth lag phase, environmental change, genetic change).change).

Lag and log Lag and log phases of spread phases of spread in in Opuntia Opuntia aurantiacaaurantiaca, South , South Africa (Moran & Africa (Moran & Zimmerman Zimmerman 1991)1991)

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1900 1930 1960 1990

Years

Are

as in

fest

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thou

sand

s of

ha

(5) Can we predict the whys (5) Can we predict the whys of an invader’s success?of an invader’s success?

Classical theories:Classical theories:Enemy Release HypothesisEnemy Release Hypothesis

Invaders’ success results from reduced natural Invaders’ success results from reduced natural enemy attack (e.g. Torchin et al. 2003 for 26 enemy attack (e.g. Torchin et al. 2003 for 26 host species of animals).host species of animals).

-0.6

-0.4-0.2

0

0.2

0.40.6

0.8

1

SpeciesRichness

Avg Prevalence Sum Prevalence Avg Prevalenceper species

Pa

rasi

te r

ele

ase

[(N

-1)/

N]

Classical theories: Classical theories: taxonomic distinctiveness taxonomic distinctiveness

Ricciardi & Atkinson 2004Ricciardi & Atkinson 2004

High-impact invaders Low-impact invaders

Shared Unshared Shared Unshared System genera genera genera genera P-value*

Laurentian Great Lakes 4 16 80 35 4E-06Hudson River 5 13 66 25 0.0005Chesapeake Bay 2 5 19 45 0.66Potomac River 2 7 34 23 0.04San Francisco Bay 1 11 44 96 0.08Port Phillip Bay 2 5 31 59 0.55New Zealand Coast 0 8 59 42 0.001

* P-values are from one-tailed Fisher Exact tests of null hypothesis that the proportion of unshared genera among high-impact invaders is no greater than that of low-impact invaders. The null hypothesis was rejected by a meta-analysis of the entire data set.

The impact of an invader should be most severe in The impact of an invader should be most severe in communities lacking similar species.communities lacking similar species.

Classical theories: invasional Classical theories: invasional meltdown (Simberloff & von Holle meltdown (Simberloff & von Holle 1999)1999)

Invader

Effects that reduce an invader’s enemies or

enhance its prey

Effects that benefit another invader (e.g. more nutrients, shelter)

Directfacilitation

Indirectfacilitation

Attractors of invaders: the Attractors of invaders: the Laurentian Great LakesLaurentian Great Lakes

The Laurentian Great Lakes as "attractors"

Date Event1880s Carp are introduced as a food source.1912 Rainbow smelt, stoked into Crystal Lake, escape into the Great Lakes.1919 Welland Canal is built between Lake Erie and Lake Ontario:

movement of the sea lamprey and white perch.1921 Sea lamprey appear in Lake Erie and later in Lake Huron, Lake Michigan,

and Lake Superior.1939 Alewife appears in Lake Huron and later in Lake Michigan.1958 Daphnia are replaced by Bosmina and Diaptomus.1960s Several salmonid fish species are stocked.1986 Ruffe, a fish from the Baltic Sea, appears.1988 Zebra mussels are discovered in Lake St. Clair and spread rapidly.1988 The spiny water flea Bythotrepes becomes abundant in Lake Michigan.1990 Round and tube nose gobies (native of the Caspian Sea) appear.1990s Exotic species continue to invade.

(6) Can we predict the whys (6) Can we predict the whys of a community’s invasibility?of a community’s invasibility?

Classical theories: species diversityClassical theories: species diversity

Species-rich communities are more resistant to Species-rich communities are more resistant to invasion (Elton 1958; MacArthur and al. 1950s-invasion (Elton 1958; MacArthur and al. 1950s-1970s; Levine & D’Antonio 1999).1970s; Levine & D’Antonio 1999).

Exceptions: Lonsdale (1999), Stohlgren et al. Exceptions: Lonsdale (1999), Stohlgren et al. (2003).(2003).Confirmations: Knops et al. (1999), Stachowicz Confirmations: Knops et al. (1999), Stachowicz et al. (1999), Kennedy et al. (2002), etc.et al. (1999), Kennedy et al. (2002), etc.

Exceptions to the “weediness” ruleExceptions to the “weediness” rule

Dominance of alien insect species in the Dominance of alien insect species in the surviving tracts of Hawaiian rainforests.surviving tracts of Hawaiian rainforests.

Water quality improvements have favored the Water quality improvements have favored the invasion of the Great Lakes by the sea lamprey, invasion of the Great Lakes by the sea lamprey, since lamprey larvae are sensitive to pollution.since lamprey larvae are sensitive to pollution.

(7) Can we predict the traits (7) Can we predict the traits that make an invader that make an invader successful and a habitat successful and a habitat susceptible to the invader?susceptible to the invader?

Generalization regarding traits of Generalization regarding traits of the invadersthe invaders

high fecundityhigh fecundity small body sizesmall body size vegetative or asexual reproductionvegetative or asexual reproduction high genetic diversityhigh genetic diversity high phenotypic plasticityhigh phenotypic plasticity broad native rangebroad native range abundant in native rangeabundant in native range physiological tolerancephysiological tolerance habitat generalisthabitat generalist human commensalismhuman commensalism loss of natural enemies loss of natural enemies invasional meltdowninvasional meltdown polyphagypolyphagy

Generalization regarding habitat Generalization regarding habitat invasibilityinvasibility

climatically matched with climatically matched with the native areathe native area

disturbeddisturbed low biodiversitylow biodiversity absence of predatorsabsence of predators presence of vacant nichespresence of vacant niches low connectance of food low connectance of food

webweb nutrient rich (plants) nutrient rich (plants)

The take-away: Kolar & Lodge The take-away: Kolar & Lodge (2001)(2001)

The most frequent and strong result in these The most frequent and strong result in these studies was that successful establishment was studies was that successful establishment was positively related to positively related to propagule pressurepropagule pressure. .

Although this result is intuitively obvious, Although this result is intuitively obvious, quantifying it is not of trivial importance with quantifying it is not of trivial importance with respect to prevention of NIS.respect to prevention of NIS.

Reducing the number of individuals released Reducing the number of individuals released and the frequency of releases reduce the and the frequency of releases reduce the probability of establishment.probability of establishment.

Point 5. PREVENTINGPoint 5. PREVENTINGPoint 5. PREVENTINGPoint 5. PREVENTING

““An ounce of An ounce of prevention is worth a prevention is worth a pound of cure.”pound of cure.”

Popular sayingPopular saying

The normative issueThe normative issue

Hard and soft lawsHard and soft laws

““Hard” or “binding” lawsHard” or “binding” laws

Global and regional multi-lateral treaties Global and regional multi-lateral treaties containing provisions on NIS introduction containing provisions on NIS introduction which, after ratification, States are then which, after ratification, States are then “bound” to implement.“bound” to implement.

At international level: The At international level: The Convention on Biological Diversity Convention on Biological Diversity (1996)(1996)

Article 8(h):Article 8(h):

In terrestrial, aquatic, and marine areas, the In terrestrial, aquatic, and marine areas, the parties, as far as possible and as appropriate parties, as far as possible and as appropriate should should “prevent the introduction of, control or “prevent the introduction of, control or eradicate those alien species which threatens eradicate those alien species which threatens ecosystems, habitats or species”. ecosystems, habitats or species”.

At European level: The Bern At European level: The Bern Convention (1979, 1982) Convention (1979, 1982)

Art. 11.2 (b):Art. 11.2 (b):

““Each Contracting Party undertakesEach Contracting Party undertakes to to strictly control the introduction of non‑native strictly control the introduction of non‑native species”species”

In 2003 the Bern Convention adopts the In 2003 the Bern Convention adopts the “European Strategy on IAS”“European Strategy on IAS”

In 2004 the Council of the In 2004 the Council of the Pan-European Pan-European Biological and Landscape Diversity Strategy - Biological and Landscape Diversity Strategy - PEBLDS launches an Action Plan on IAS for PEBLDS launches an Action Plan on IAS for the implementation of the Strategythe implementation of the Strategy

AIM:AIM: development and implementation of development and implementation of coordinatedcoordinatedmeasures and cooperative efforts to measures and cooperative efforts to minimise adverse impacts of IAS on minimise adverse impacts of IAS on Europe’s biodiversity, economy and human Europe’s biodiversity, economy and human health and wellbeinghealth and wellbeing1.1. Building awareness and support Building awareness and support 2.2. Collecting, managing and sharing Collecting, managing and sharing

informationinformation3.3. Strengthening national policy, Strengthening national policy,

legal and institutional frameworks legal and institutional frameworks 4.4. Regional cooperation and Regional cooperation and

responsibility responsibility 5.5. PreventionPrevention6.6. Early detection and rapid Early detection and rapid

response response 7.7. Management of impactsManagement of impacts8.8. Restoration of native biodiversityRestoration of native biodiversity

European Strategy on IAS (December European Strategy on IAS (December 2003)2003)  

At European level: the “birds” At European level: the “birds” (1979) and “habitats” (1992) (1979) and “habitats” (1992) directivesdirectives

Birds directive, art. 11:Birds directive, art. 11:

““Member States shall see that any introduction of Member States shall see that any introduction of species of bird which does not occur in the wild species of bird which does not occur in the wild state in the European territory of the member state in the European territory of the member States does not prejudice the local flora and fauna”.States does not prejudice the local flora and fauna”.

Habitats directive: art. 22(b):Habitats directive: art. 22(b):

““Member States shall ensure that the deliberate Member States shall ensure that the deliberate introduction into the wild of any species which is introduction into the wild of any species which is not native to their territory is regulated so as not to not native to their territory is regulated so as not to prejudice natural habitats within their natural range prejudice natural habitats within their natural range or the wild native fauna and flora and, if they or the wild native fauna and flora and, if they consider it necessary, prohibit such introductions”.consider it necessary, prohibit such introductions”.

““Soft” laws and technical guidance Soft” laws and technical guidance documentsdocuments

They set out the responsibilities of various They set out the responsibilities of various actors –both public and private- involved with a actors –both public and private- involved with a particular activity and recommend practices particular activity and recommend practices and procedures to diminish the risk of a and procedures to diminish the risk of a particular introduction.particular introduction.

List of soft law documentsList of soft law documents

Recommendation No. R(84)14 of the Committee of Ministers Recommendation No. R(84)14 of the Committee of Ministers to the Council of Europe Member States Concerning the to the Council of Europe Member States Concerning the Introduction of Non-native Species (1984)Introduction of Non-native Species (1984)

The International Maritime Organization (IMO) Guidelines for The International Maritime Organization (IMO) Guidelines for Preventing the Introduction of Unwanted Aquatic Organisms Preventing the Introduction of Unwanted Aquatic Organisms and Pathogens from Ships’ Ballast Water and Sediment and Pathogens from Ships’ Ballast Water and Sediment Disharges (1993)Disharges (1993)

The UN Food and Agriculture Organization (FAO) Code of The UN Food and Agriculture Organization (FAO) Code of Conduct for the Import and Release of Exotic Biological Conduct for the Import and Release of Exotic Biological Control Agents (1995)Control Agents (1995)

The aquaculture provisions of the FAO Code of Conduct for The aquaculture provisions of the FAO Code of Conduct for Responsible Fisheries (1995)Responsible Fisheries (1995)

The International Council for the Exploration of the Seas The International Council for the Exploration of the Seas (ICES)/European Inland Fisheries Advisory Commission (EIFAC) (ICES)/European Inland Fisheries Advisory Commission (EIFAC) Code of Practice of the Introductions and Transfers of Marine Code of Practice of the Introductions and Transfers of Marine Organisms (1994)Organisms (1994)

The IUCN Position Statement on Translocation of Living The IUCN Position Statement on Translocation of Living Organisms (1987)Organisms (1987)

““Bugs” in laws and regulations: the Bugs” in laws and regulations: the case of the Great Lakescase of the Great Lakes

Since 1989, vessels that declare “ballast on Since 1989, vessels that declare “ballast on board” (BOB) status (but not NOBOB vessels) are board” (BOB) status (but not NOBOB vessels) are subject to the “voluntary ballast water exchange” subject to the “voluntary ballast water exchange” regulation. The number of introductions regulation. The number of introductions increased.increased.

05

1015202530354045

1959 1964 1969 1974 1979 1984 1989 1994 1999

Year

Cum

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peci

es

To face NIS: Action 1To face NIS: Action 1

THE LEGAL ACTION:THE LEGAL ACTION:

Applying the preventative and precautionary Applying the preventative and precautionary approaches to all NIS introductions: presumed approaches to all NIS introductions: presumed guilty (New Zealand) better than presumed guilty (New Zealand) better than presumed innocent (Australia and USA). innocent (Australia and USA).

Creating a general prohibition on international Creating a general prohibition on international introductions, without authorization from a introductions, without authorization from a competent authority. competent authority.

To face NIS: Action 2To face NIS: Action 2

THE ECONOMIC ACTION:THE ECONOMIC ACTION:

Providing adequate financial resources, Providing adequate financial resources, establishing incentive/disincentive measures establishing incentive/disincentive measures (e.g. insurance requirements, civil fines, (e.g. insurance requirements, civil fines, criminal penalties and fines, fees and criminal penalties and fines, fees and corrective taxes), to prevent NIS introductions.corrective taxes), to prevent NIS introductions.

To face NIS: Action 3To face NIS: Action 3

THE PSYCHOLOGICAL ACTION:THE PSYCHOLOGICAL ACTION:

Obviating the demand for exotic species by Obviating the demand for exotic species by shifting the public interest towards the use of shifting the public interest towards the use of indigenous species.indigenous species.

To face NIS: Action 4To face NIS: Action 4

INTERNATIONALIZATION:INTERNATIONALIZATION:

Promoting international Promoting international cooperation and coordination.cooperation and coordination. Developing a broadly accessible Developing a broadly accessible network of information.network of information.

To face NIS: Action 5To face NIS: Action 5

THE COGNITIVE ACTION:THE COGNITIVE ACTION:

Requiring pre-introduction environmental risk Requiring pre-introduction environmental risk assessment (about: assessment (about: disease, ecology, genetics, socio-economics, local species impacted) as a minimum pre-requisite to as a minimum pre-requisite to obtain a permit.obtain a permit.

Monitoring after introduction.Monitoring after introduction. Identifying and controlling pathways of Identifying and controlling pathways of

accidental introductions. accidental introductions.

To face NIS: Action 6To face NIS: Action 6

THE EDUCATIONAL ACTION:THE EDUCATIONAL ACTION: Conducting public education Conducting public education and awareness campaigns. and awareness campaigns. Circulating information by Circulating information by communicating with all communicating with all stakeholders.stakeholders.

Point 6: MANAGINGPoint 6: MANAGINGPoint 6: MANAGINGPoint 6: MANAGING

Humans “can always Humans “can always be counted on to do be counted on to do the right thing - after the right thing - after they have exhausted they have exhausted all other possibilities.“all other possibilities.“

Winston Churchill Winston Churchill (mod.)(mod.)

Is the science required for a quick Is the science required for a quick action minimal? Simberloff (2003)action minimal? Simberloff (2003)

A quick and dirty response, mechanical or A quick and dirty response, mechanical or chemical or both, often solves the problem at chemical or both, often solves the problem at the outset by eliminating the invader. the outset by eliminating the invader.

The dangers of slow responsesThe dangers of slow responses

A slow response: A slow response: Caulerpa taxifoliaCaulerpa taxifolia in the Mediterraneanin the Mediterranean

1984/96 discussion within the academic world 1984/96 discussion within the academic world

on the origin and impact of on the origin and impact of Caulerpa taxifoliaCaulerpa taxifolia

1984 First detected 1 m2

1989 1 ha

1990 3 ha1991 31 ha

In 1996, eradication is not possibleIn 1996, eradication is not possible

A quick response: carp (Cyprinus carpio) in Southern Spain

Zóñar Lagoon is: One of the few remaining

permanent lagoons in a semiarid region

Wintering habitat for more than 5,000 of aquatic birds

One of the few refuges of the endangered White-headed Duck

Included in the Ramsar Convention

Declared Natural Reserve by the Spanish Parliament

Designated by the EU “Special Area for Bird Protection”

Rotenone product CFT Legumine®

Dr. Carlos Fernández-Delgado, University of Córdoba, SpainMr. Rafael Arenas González, Environmental Regional Agency, Junta de Andalucía, SpainMr. Gunnar Persson, InterAgro AB, Sweden

June 2006 – few plants June 2007 – increased plants

17

1

16

02468

1012141618

1980-84 1993 Oct'06-May'07

Withoutcarp

Withoutcarp

Withcarp

Num

ber

of g

ener

a

Aquatic insectsAquatic insects

In one year without carp the condition of the lake has changed !!!

250

Grey Heron

Great Cormorant

Common Pochard

White-Headed Duck

050 50 100 150100150200

Number of specimens

Without carp

(Jan-June 07)

With carp(Jan-June 00-02)

Changes in Bird Community

Responses may be too quick: The Responses may be too quick: The saga of the rat control on the saga of the rat control on the islands of Micronesiaislands of Micronesia

1930s:1930s: Giant monitor lizard (Giant monitor lizard (MegalaniaMegalania) ) was introduced to was introduced to prey on rats: but it is diurnal, the rat is nocturnal, so the prey on rats: but it is diurnal, the rat is nocturnal, so the monitor started to prey on poultry.monitor started to prey on poultry.

1945:1945: Cane toad (Cane toad (Bufo marinusBufo marinus) was introduced as an ) was introduced as an alternative prey: its venom killed the monitors, the toad alternative prey: its venom killed the monitors, the toad population exploded. Cats and dogs were killed by the population exploded. Cats and dogs were killed by the toads’ venom and the giant African snails, toads’ venom and the giant African snails, AchatinaAchatina (introduced in the 1940s), exploded on the carrion of their (introduced in the 1940s), exploded on the carrion of their carcasses.carcasses.

1970s-1980s:1970s-1980s: Flatworms were introduced to control the snail Flatworms were introduced to control the snail but they started to spread.but they started to spread.

To make responses effective:To make responses effective:a duty of scientistsa duty of scientists

Managing IAS requires a Managing IAS requires a hierarchical approachhierarchical approach

1) Prevention of new introductions2) Early detection-rapid response 3) Eradication of established IAS when

feasible4) When eradication not feasible,

maintenance control at acceptable level, if appropriate

Guiding Principles on IAS (Decision VI/23 on Alien Species that threaten ecosystems, habitats and species; COP-VI, The Hague, April 2002)

What is spent provides monetary What is spent provides monetary returnsreturns

Every dollar spent … Every dollar spent … … … suppressing the sea lamprey in the Great suppressing the sea lamprey in the Great

Lakes returns Lakes returns $30.25$30.25 in increased fisheries in increased fisheries revenues.revenues.

… … preserving wetland ecosystems by preserving wetland ecosystems by eradicating purple loosestrife returns eradicating purple loosestrife returns $27$27..

… … preventing pest invasion from the imports of preventing pest invasion from the imports of Siberian logs returns Siberian logs returns $1,661$1,661..

Eradication may fail Eradication may fail

In European freshwater:In European freshwater: No cases of eradication of aquatic No cases of eradication of aquatic invertebrates or plant species.invertebrates or plant species. Eradication of the monogenean parasite of salmon, Gyrodactylus salaris, failed in Norway (despite 151,694 Euro expended).

Eradication may succeedEradication may succeed

In European freshwater:In European freshwater: Two fish species (Two fish species (Pseudorasbora parva in U.K. and Cyprinus carpioCyprinus carpio in Spain) in Spain) Canadian beaver in FranceCanadian beaver in France Muskrat in Pertshire and Sussex, U.K.Muskrat in Pertshire and Sussex, U.K. American Mink in Hiimaa island, EstoniaAmerican Mink in Hiimaa island, Estonia

……and the coypu in East Anglia and the coypu in East Anglia (U.K.)(U.K.)

Lasted 9 years (1981-1990) and required: 24 trappers, 40-Lasted 9 years (1981-1990) and required: 24 trappers, 40-50 traps per person, 10-15 rafts, 4-5 boats, leading to 50 traps per person, 10-15 rafts, 4-5 boats, leading to 31,822 coypus killed (Gosling et al., 1981; Gosling & 31,822 coypus killed (Gosling et al., 1981; Gosling & Baker, 1999). Baker, 1999).

Costs, actualised to yr 2000, amounted to about 5 million Costs, actualised to yr 2000, amounted to about 5 million €.€.

0

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4000

6000

8000

10000

12000

14000

16000

1978 1980 1982 1984 1986 1988 1990

Factors of the successFactors of the success

1)1) Sufficient resources were devoted for a Sufficient resources were devoted for a long enough timelong enough time

2)2) There was a widespread support both from There was a widespread support both from the relevant agencies and the publicthe relevant agencies and the public

3)3) Two consecutive winters were particularly Two consecutive winters were particularly coldcold

4)4) The intervention respected the biology of The intervention respected the biology of the target speciesthe target species

5)5) There was a constant interaction between There was a constant interaction between managers and scientistsmanagers and scientists

The moral of the story …The moral of the story …

BioinvasionsBioinvasions are important are important

BioinvasionsBioinvasions are appealing are appealing

Bioinvasions Bioinvasions are partially understoodare partially understood

Bioinvasions Bioinvasions are highly debatedare highly debated

BioinvasionsBioinvasions are poorly managed are poorly managed

BioinvasionsBioinvasions require a prompt but require a prompt but balanced and coordinated action …balanced and coordinated action …

The Nero dilemma can be The Nero dilemma can be solved !!!solved !!!The Nero dilemma can be The Nero dilemma can be solved !!!solved !!!

……in which scientistsin which scientistsplay a key role.play a key role.