Slide 1: title
Slide 2: Could a newly discovered parasite in an abundant estuary shrimp be introduced?
- Can it threaten its new host?
- Is “biodiversity” important?
- Is evolution important?
- Should other species be expected to fill in for species that are lost?
Slide 3: “Introduced” species are reproductive populations transported to a new location across a major natural barrier by human activities.
- They have characteristics inconsistent with native species that indicate they did not co-evolve.
- These inconsistent characters are the “criteria” for introduced species.
Slide 4: Types of Species Origins:
- Indigenous (Native)
- Cryptogenic
- Indeterminate
- Nonindigenous (Introduced by humans)
Slide 5: The inconsistent characters “criteria” for introduced species
Slide 6: Orthione griffenis Markham, 2004
Slide 7: (photo)
Slide 8:Orthione griffenis Markham, 2004, Yaquina Bay
First records: Washington 1988; Oregon early 1980s; California early 1990s
Slide 9: Chart: Bopyrid length with year of discovery (1857 - 2004) including Orthione griffenis and all western US pelagic and nearshore benthic bopryid isopods, and predicted sizes of nearshore benthic species [excluding O. griffenis] (line) Length=150.24+year*-.0742, df = 13, p < .001).
Slide 10: Geography / Taxonomy
Orthione griffenis is amphi-Pacific:
- NEP – John Markham 2004
- Host: Upogebia pugettensis
NWP – Gyo Itani (Japan) found O. griffenis in
- Upogebia issaeffi
- Austinogebia narutensis
Slide 11: Mechanism
A marine dependent NEP invader?
Slide 12: Mechanism
Ballast water = zooplankton hosts = cryptoniscans
Slide 13: 1) Orthione griffenis is introduced
- Timing - Not seen before
- Taxonomy / Geography - Asia & North America
- Transport mechanism - ballast water
- Ecology: Bopyrids castrate hosts
- What happens to the new hosts?
- What are the effects of this new parasite?
Slide 14: Explosion after 1997 with:
- Carcinus maenus north
- Nuttallia obscurata south
- Anomolous? oceanographic conditions
Orthione is a full marine invader:
- It is the second marine invasion since Attya armatum
- It is a ballast water introduction as important as Corbula amurensis?
Slide 15: (Chart: Introduced species are not coevolved
Terrestrial extinctions follow invasions but few marine examples are reported
Slide 16: (Map) Geography of modern diversity (Wallace, 1876)
Slide 17: (Chart) Evolution of modern biodiversity
Slide 18: (Chart) Island Biogeography: species area (Wilson & Bossert, 1972)
Slide 19: (Chart) Island Biogeography: species equilibrium (Wilson & Bossert, 1972)
Slide 20: Isolation over time and space created modern biodiversity and human wealth
Natural barriers to aquatic species dispersal:
- Continents and oceans
- Counter currents and thermal gradients
- Diverse climates
Species diverged in similar isolated climates until the homocene
Slide 21: Reunite Pangaea
- “Introduced” species crossed natural barriers to dispersal
- More species in each place but less species everywhere
Slide 22: (Chart) Predator - prey evolution (including humans) (Wilson & Bossert, 1972)
Slide 23: Coevolution among native species results in sustainable (Lotka – Volterra) interactions
- Prey become rare when predators increase
- Predators become rare when prey decrease
- Other interactions lead to extinction
- Introduced species are not coevolved and in their new systems
- Predators and parasite “release” is possible with introductions
- But then, evolutionary and ecological theory need not apply
- Unsustainable interactions are possible
Slide 24: (Photo) Upogebia pugettensis
Slide 25: (Chart) Parasite characteristics that affect host populations:
Slide 26: 1) Affects host
(Chart) Wet weight of Yaquina Bay Upogebia pugettensis by carapace length May and July 2005
Slide 27: (Map)
Slide 28: (Chart) Cedar River Upogebia 1988-2004
Willapa Bay Upogebia pugettensis and Orthione griffenis 1988-2004
Slide 29: 2) Increased host mortality?
Slide 30: (Chart) Orthione does not increase mortality of experimentally starved adults
Slide 31: (charts) Field observations: mortality due to starvation unlikely
Slide 32: Not mortality? 3) Decreases reproduction?
Slide 33: (Chart) Gun samples: Estimated fecundity
Slide 34: (Chart) Lost fecundity
Slide 35: (Map) Reproductive or recruitment failure
Slide 36: (Map) Spatial variation
Slide 37: (Chart) Declines are not universal – 2 Upogebia populations are constant or increasing 2005-07 while Goose Point is down to < 20 m -2
Slide 38: 4) Decreases recruitment
- Spatial and temporal variation
- With ocean conditions
- Among populations
- Among estuaries
Slide 39: (Illustration) Burrowing Shrimp Life History
Slide 40: (chart) Index of settling megalopae
Slide 41: (chart) Spring transition (day of year)
Slide 42: (Chart) Upogebia Life History - Variable recruitment
Slide 43: 4) Decreases recruitment
- Ocean conditions are likely to be important
- Do ocean conditions control Upogebia populations?
Slide 44: (Photo) Upogebia aggregate
Slide 45: (Chart) Upogebia self recruit (density dependent settlement)
Slide 46: Could Orthione limit recruitment?
Slide 47: (Map) What About Elsewhere?
Slide 48: 5) Parasite attraction to host
Orthione recruitment independent of host density
Slide 49: (chart) Orthione prevalence-density independent
Slide 50: Mechanism: Aggregation may increase vulnerability
- Solitary
- Agonistic
- Annual mating
- Burrow dependant survival
- Connect burrows to find mates
Slide 51: (Chart)
Slide 52: (Chart) 1) Affects host: Wet weight of Yaquina Bay Upogebia pugettensis by carapace length May and July 2005
Slide 53: (Chart) Frequency by female carapace length
Slide 54: 6) Parasite surplus
Orthione recruitment enough for all Upogebia
Slide 55: (Chart) Parasite surplus?
Slide 56: Extinction possible?
- Orthione may not play by “the rules”
- Orthione severely reduces host reproduction
- Orthione recruits independent of host density
- Do Orthione overlap the entire Upogebia pugettensis distribution?
Slide 57: Emerging questions:
- Are Upogebia populations declines continuing and are we measuring them?
- What consequences = ecosystem alterations - trophic cascades will occur with Upogebia declines?
- Are there management options to save Upogebia?
- What is the natural history and ecology of Orthione?
- What is the global distribution of O. griffenis?
- Only Japan and NEP?
- Are Thalassinidea of other geographical areas infested?
- What are the origins and genetic/species diversity of Orthione?
- How diverse are Pacific and Atlantic Orthione species?
- Have ocean conditions contributed to Orthione’s introduction?
- Are there opportunities for biological control and conservation?
- Could there be economic effects?
Slide 58: Chart: Estuarine influence on salmon survival (Magnusson & Hilborne 2003. Estuaries 26(4B):1094-1103)
Slide 59: (Chart) Higher trophic levels?
Slide 50: (Chart) Upogebia deposit eggs in fall that hatch in spring – a salmon refuge?
Slide 61: (Chart) Siletz Estuary 1998
Slide 62: (Chart) Midwest Coho smolts, 1997, weight of stomach contents as % of fishes
Slide 63: (Chart) Upogebia larvae a lost buffer to ocean conditions
Slide 64: Project credits
(For more information contact the author at john.chapman@oregonstate.edu)