Are Cryptoniscans waiting
for a good home?
Kelsey Yates
BI 401
Summer Marine &
Environmental Studies Program
Summer 2014
Connections
• Katie Crooks: Cryptoniscans
are waiting
• Amber Little and the SNRC:
Bopyrids are not recruiting
or growing
• Kelsey Yates: Why?
Orthione griffenis
Microniscan
• Bopyrid form
Epicaridan
Upogebia
pugettensis
eggs
Cryptoniscan
Bopyridan
Upogebia pugettensis
• Populations decline due to castration
• How this happens has been unclear
Smith et al. 2008, Dumbauld et al. 2011, Chapman et al. 2012
Previous Studies
Smith et al. 2008
• No correlation between host weight
loss and isopod size
Repetto and Griffen 2011
• No correlation between bopyrid size and
mass of hepatopancreas
– Hepatopancreas is a supposed energy storage
organ in shrimp
• Also found no relationship between infested
shrimp and hepatopancreas mass
SNRC Data
• Maximum Orthione size increase with Upogebia size
• High occurrence of small Orthione in samples of all sizes of
shrimp
• Orthione not found in small shrimp (<12 mm)
• Reproducive Orthione (area of ~60 mm2) are not found in
shrimp with carapace length <15mm
Questions
• How do Orthione effect the mass of the shrimp over time?
– Not examined before
• What is the growth rate of Orthione?
• Do infested shrimp lose more weight than uninfested shrimp
over time?
Predictions
• Smaller isopods in large shrimp would have the highest
growth rate
• Greatest weight loss observed would be of infested shrimp
Infested and uninfested shrimp collected from Sally’s Bend mud
flat in the Yaquina Bay estuary on July 26th, 2014 with help from
the Summer Natural Resources Crew
Data Collection
Test groups: Uninfested, Infested, Implanted
Weighed and
measured Upogebia
Weighed and measured
Orthione
Area=size=(L/2*W/2)π
Uninfested shrimp
implanted with small
Orthione
Series of gutters delivered ocean water 24/7 for 14 days
Shrimp in individual cups
Measured individuals a total of 5 times during study
• alfjhdjalhd
• Higher death rate among infested shrimp
• High occurrence of unknown disease causing
ballooned or black carapaces in shrimp
Death Rate/Day
0
-0.025
-0.02
Uninfested
-0.015
-0.01
Implanted
-0.005
Infested
0
Results
•
No correlation between shrimp weight loss and isopod size
– Rate of weight loss calculated using: rw = ln(W1/W0)/t
• No difference in weight loss among treatments
– Infested: -0.003, Implanted: -0.004, Uninfested: -0.004
Shrimp change in mass per day vs
Isopod area
Shrimp mass (g) vs rate of weight loss
0.000
200.0
0
5
10
15
20
25
-0.001
180.0
Isopod Area (square mm)
y = -6952.4x + 23.759
R² = 0.0974
140.0
-0.003
120.0
-0.004
100.0
-0.005
80.0
-0.006
60.0
-0.007
40.0
20.0
-0.012
Change in mass per day
-0.002
160.0
-0.010
-0.008
-0.006
-0.004
-0.002
Shrimp Change in Mass per Day
0.0
0.000
-0.008
-0.009
Shrimp Mass (g)
Infested (I)
Implanted (P)
Uninfested (U)
Results
• Isopods had no measurable growth
– Use more accurate scale in future
0.1
Initial Area vs Final Area Isopod
Isopod Area vs Change in Mass
180.000
140.000
final = 0.8685(initial) + 0.6645
R² = 0.9917
0.06
Change in mass per day
160.000
0.08
Final Area
120.000
100.000
80.000
60.000
0.04
0.02
0
40.000
0.0
20.000
50.0
100.0
-0.02
0.000
0.0
50.0
100.0
Initial Area
150.0
200.0
-0.04
Isopod Area
150.0
200.0
Discussion
• Infested shrimp did not lose more weight than
uninfested shrimp in lab
– Isopods did not use the shrimp’s resources at a measurable
rate
– Isopods may have been starving along with shrimp
• Isopods did not to grow
– Isopods grow with their hosts
– Upogebia growth is cyclical (Food sources must be as well)
– Isopods may only feed when shrimp have adequate energy
stores
– May be why isopods only infest larger shrimp (>15mm)
Amber Little and SNRC Data Collection
• No recruitment or growth of isopods in the field
• Experimental results consistent with field data
Conclusions
• Cryptoniscans wait
– Katie’s Study
• Maybe they have no
homes right now
Suggestions For
Improvement
• Some incidence of isopods being lost
– Recommend implanting the isopod far up under the
gill covering to limit removal by shrimp
• High incidence of infections
– Recommend use of antibiotics to limit chance of
infection
• High Incidence of death in infested shrimp
– Recommend measuring shrimp less to limit stress
associated with removing and re-implanting isopods
Thank You!
Acknowledgements:
• John Chapman
• Andrea Burton
• Amber Little and the SNRC
• Itchung Cheung
• HMSC
Questions?
Sources
•
•
•
•
•
•
Ralph A. Breitenstein 1* John W. Chapman 2 Craig Bauer3 (Unpublished MS) Ecology of Orthione
griffenis and Iona cornuta larvae (Isopoda, Bopyridae) in an Oregon Estuary
Chapman, J. W., Dumbauld, B. R., Itani, G., & Markham, J. C. 2012. An introduced Asian parasite
threatens northeastern Pacific estuarine ecosystems. Biological Invasions, 14, 12211236.
Dewitt, T. H., A. F. D’Andrea, C. A. brown, B. D. Griffen, and P. M. Aldridge. 2004. Impact of burrowing
shrimp populations on nitrogen cycling and water quality in western North American temperate
estuaries, p. 107–118. In A. Tamaki [ed.], Proceedings of the symposium on ecology oflarge
bioturbators in tidal flats and shallow sublittoral sediments—from individual behavior to their role as
ecosystem engineers. Univ. of Nagasaki.
Dumbauld, B. R., Chapman, J. W., Torchin, M. E., & Kuris, A. M. 2010. Is the Collapse of Mud Shrimp
(Upogebia pugettensis) Populations Along the Pacific Coast of North America Caused by Outbreaks of
a Previously Unknown Bopyrid Isopod Parasite (Orthione griffenis)?. Estuaries and Coasts, 34, 336-350.
Repetto, M., and B. D. Griffen. 2011. Physiological consequences of parasite infection in the burrowing
mud shrimp, Upogebia pugettensis, a widespread ecosystem engineer. Marine and Freshwater
Research 63: 60-67.
Smith, Andrew E. , John W. Chapman, and Brett R. Dumbauld. 2008. "Population Structure and
Energetics of the Bopyrid Isopod Parasite Orthione griffenis in Mud Shrimp Upogebia pugettensis."
Journal of Crustacean Biology 28: 228-233. Print.