Journal Club 11-02-2011. Parasites and Biological Invasion

1. Department of Biodiversity and Molecular Ecology
Journal Club
matteo.marcantonio@fmach.it
February 11, 2015
(Fondazione Edmund Mach) Journal Club, DBEM February 11, 2015 1 / 23

2. The review in a nutshell
Rationale
The distribution of species is rapidly changing.
Biological invasion/disease emergence are key processes in species redistribution.
Biological invasion and disease emergence are interlinked.
Aim
Examine the parasitism-invasion reciprocal influence.
Explore the consequences on species, communities and ecosystems.
Discuss how to mitigate these threats through biosecurity.
Outcome
Lack of international cooperation on invasive species and parasites of
wildlife favours their spread.
Irreversible ecological changes are possible.
New perspectives in invasion ecology/parasitology should be explored.
(Fondazione Edmund Mach) Journal Club, DBEM February 11, 2015 2 / 23

3. Why the distribution of species is changing so quickly?
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Something missing?
(Fondazione Edmund Mach) Journal Club, DBEM February 11, 2015 3 / 23

4. Human impacts result in a new geologic era:
The Anthropocene. aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa
*Steffen, Grinevald, Crutzen, McNeill, Phil. Trans. R. Soc. A (2011) 369,842-867.
Which main ecological characteristic is “Ecological novelty”.aaaaa
Invasions are one of the main generators of ecological novelty.aaa
Parasites are frequently partners or players in biological invasions.
(Fondazione Edmund Mach) Journal Club, DBEM February 11, 2015 4 / 23

5. The Parasite, the Invader and the Native (species)
“In this world there’s two kinds of people, my friend: Those with loaded guns and those
who dig (cit. The Good, the Bad and the Ugly).”
Invasive parasites drive changes in host species diversity.
Invasive species lead to novel parasite-host combinations.
Invasive species influence endemic diseases.
If less-competent hosts for an endemic parasite, then parasite
dilution may occur.
Invasive species may lose their parasites in the course of invasion.
Parasites can change invasion outcomes through effects on host
behavior and life history.
The effect of invaders on native species may influence
parasite-host interactions.
(Fondazione Edmund Mach) Journal Club, DBEM February 11, 2015 5 / 23

6. Worldwide amphibian decline
Habitat loss, pollution, hunting, and EID chytridiomycosis
(Fondazione Edmund Mach) Journal Club, DBEM February 11, 2015 6 / 23

7. The Parasite, the Invader and the Native (species)
“In this world there’s two kinds of people, my friend: Those with loaded guns and those
who dig (cit. The Good, the Bad and the Ugly).”
Invasive parasites drive changes in host species diversity.
Invasive species lead to novel parasite-host combinations.
Invasive species influence endemic diseases.
If less-competent hosts for an endemic parasite, then parasite
dilution may occur.
Invasive species lose their parasites in the course of invasion.
Parasites change invasion outcomes through effects on host
behavior and life history.
The effect of invaders on native species may influence
parasite-host interactions.
(Fondazione Edmund Mach) Journal Club, DBEM February 11, 2015 7 / 23

8. Pox virus in Sciurus spp
Avirulent to its original host, high mortality in the new host
(Fondazione Edmund Mach) Journal Club, DBEM February 11, 2015 8 / 23

9. The Parasite, the Invader and the Native (species)
“In this world there’s two kinds of people, my friend: Those with loaded guns and those
who dig (cit. The Good, the Bad and the Ugly).”
Invasive parasites can drive changes in host species diversity.
Invasive species may lead to novel parasite-host combinations.
Invasive species influence endemic diseases.
If the invader is a less-competent host for an endemic parasite, then
parasite dilution may occur.
Invasive species may lose their parasites in the course of invasion.
Parasites can change invasion outcomes through effects on host
behavior and life history.
The effect of invaders on native species may influence
parasite-host interactions.
(Fondazione Edmund Mach) Journal Club, DBEM February 11, 2015 9 / 23

10. Leafhoppers-parasitoid interactions
The invasive works as reservoir for the parasitoid, which preferentially attacks the native
(a) Native (b) Parasitoid
(c) Invader
(Fondazione Edmund Mach) Journal Club, DBEM February 11, 2015 10 / 23

11. The Parasite, the Invader and the Native (species)
“In this world there’s two kinds of people, my friend: Those with loaded guns and those
who dig (cit. The Good, the Bad and the Ugly).”
Invasive parasites can drive changes in host species diversity.
Invasive species may lead to novel parasite-host combinations.
Invasive species can influence endemic diseases.
If the invader is a less-competent host for an endemic parasite, then
parasite dilution may occur.
Invasive species may lose their parasites in the course of invasion.
Parasites can change invasion outcomes through effects on host
behavior and life history.
The effect of invaders on native species may influence
parasite-host interactions.
(Fondazione Edmund Mach) Journal Club, DBEM February 11, 2015 11 / 23

12. Invasive trout sink for trematode infections
(Fondazione Edmund Mach) Journal Club, DBEM February 11, 2015 12 / 23

13. The Parasite, the Invader and the Native (species)
“In this world there’s two kinds of people, my friend: Those with loaded guns and those
who dig (cit. The Good, the Bad and the Ugly).”
Invasive parasites can drive changes in host species diversity.
Invasive species lead to novel parasite-host combinations.
Invasive species influence endemic diseases.
If less-competent hosts for an endemic parasite, then parasite
dilution may occur.
Invasive species lose their parasites in the course of invasion.
Parasites change invasion outcomes through effects on host
behavior and life history.
The effect of invaders on native species influence parasite-host
interactions.
(Fondazione Edmund Mach) Journal Club, DBEM February 11, 2015 13 / 23

14. The Parasite, the Invader and the Native (species)
“In this world there’s two kinds of people, my friend: Those with loaded guns and those
who dig (cit. The Good, the Bad and the Ugly).”
Invasive parasites drive changes in host species diversity.
Invasive species lead to novel parasite-host combinations.
Invasive species influence endemic diseases.
If less-competent hosts for an endemic parasite, then parasite
dilution may occur.
Invasive species lose their parasites in the course of invasion.
Parasites change invasion outcomes through effects on host
behavior and life history.
The effect of invaders on native species influence parasite-host
interactions.
(Fondazione Edmund Mach) Journal Club, DBEM February 11, 2015 14 / 23

15. Echinoryncus modifies alien-native/prey-predator system
Ecological novelty generates by parasites
(g) Invader (h) Parasite (i) Native
(Fondazione Edmund Mach) Journal Club, DBEM February 11, 2015 15 / 23

16. The Parasite, the Invader and the Native (species)
“In this world there’s two kinds of people, my friend: Those with loaded guns and those
who dig (cit. The Good, the Bad and the Ugly).”
Invasive parasites drive changes in host species diversity.
Invasive species lead to novel parasite-host combinations.
Invasive species influence endemic diseases.
If less-competent hosts for an endemic parasite, then parasite
dilution may occur.
Invasive species lose their parasites in the course of invasion.
Parasites change invasion outcomes through effects on host
behavior and life history.
The effect of invaders on native species influence parasite-host
interactions.
(Fondazione Edmund Mach) Journal Club, DBEM February 11, 2015 16 / 23

17. Tremadote diversity decrease with invasive snail abundace
(j) Invader snail (k) Native (l) Trematode diversity
(Fondazione Edmund Mach) Journal Club, DBEM February 11, 2015 17 / 23

18. High-level ecological consequences of invading parasites
Host-parasite invasions contribute to ecological novelty at
ecosystem or landscape scale.
Wildlife EIDs are responsible for some of the most dramatic biotically
driven landscape change in recent history.
Parasites may play key roles in ecosysyem function and are
important components of biological diversity.
Parasites can dramatically alter the characteristics of food webs.
Parasites can have effect on biodiversity.
Disease-biodiversity relationship complex and highly controversial.
Feedback between parasite prevalence, invaders and biodiversity can
lead to new community configuration.
As a result, irreversible changes are possible.
(Fondazione Edmund Mach) Journal Club, DBEM February 11, 2015 18 / 23

19. Stage-specific control strategies of biological invasions and disease emergence
(Fondazione Edmund Mach) Journal Club, DBEM February 11, 2015 19 / 23

20. Policy to control invasive species and emerging diseases
International policy on EIDs of humans, managed animals and plants
is led by WHO.
On the contrary parasites and wildlife without direct human medical
or economic impact fall between the gaps of many regulatory bodies.
Their environmental, indirect economic or medical impact may be
substantial.
International cooperation, in absence of International legislation is
hampered by the prisoner’s dilemma nature of this interaction.
As a consequence the most effective current invasive-species
legislation tends to be at national levels (Australia, New Zeland).
EU is putting into place Invasive Alien Species legislation that will
identify invasive species.
Is critical that this legislation will include parasites of humans,
managed populations and wildlife.
(Fondazione Edmund Mach) Journal Club, DBEM February 11, 2015 20 / 23

21. Risk analyses and management to limit new invasions
• Risk (probability*consequences) assessments enable the identification
of high-risk scenarios and to target resources.
• Reliable risk assessments require accurate quantification.
• Difficult to achieve for invasions as the their likelihood is a function of
numerous biotic and abiotic interactions.
• Quantification depends on the adopted spatio-temporal scale.
• Issues involving public perception can make risk management
problematic due to irrational behaviours.
• Countries may take a defensive approach to border control for imports
because they reap the benefits of biosecurity directly.
• By contrast, the cost of export biosecurity measures is born by the
originating country alone, while the benefits accrue to all countries in
receipt of the exports.
(Fondazione Edmund Mach) Journal Club, DBEM February 11, 2015 21 / 23

22. Final remarks
Biological invasions lead to novel parasite-host interactions and
transmission opportunities.
Control of invasions and wildlife diseases is key to limit the risk of
human EIDs.
Many parallels in control strategies for EIDs and invasive species.
Preventing their introduction is the most cost-effective action.
Call for an effective International legislation.
Despite prevention, some biological invasions and EIDs will
succeed.
Mitigations and eradications are not always cost effective nor
successful.
We will be obliged to accept a degree of novelty in our
ecosystems, including novel hosts and parasites.
New ecological paradigms for invasion biology will arise.
(Fondazione Edmund Mach) Journal Club, DBEM February 11, 2015 22 / 23

23. New paradigms in ecology?
(Fondazione Edmund Mach) Journal Club, DBEM February 11, 2015 23 / 23