Laser Ablation – Inductively
Coupled Plasma – Mass
Spectrometer
(LA-ICP-MS)
An Alternative To The
Electron Microscope
Introduction
• Strontium otolith marking: a successful mass marking
technique.
• Benefit have been a hatchery component that is 100%
marked.
• Drawbacks,
–
–
–
–
Expensive.
Labor intensive.
Extensive prep work.
Not capable of distinct mark for each of the three lakes.
Electron Microscope
The Strontium Marked Otoliths
ICP-MS methods
•
•
•
•
•
•
Analyses metals
GAS, Liquid, Solids
Laser is sample introduction
5u to 200u line sizes
45 element at 1 – 5 ppt mdl
1 minute per sample analyses
LA-ICP-MS
Strontium Concentrations in Marked and
Unmarked Otoliths
0.06
0.030
Sr/Ca concentration in a non spiked otolith
0.05
0.025
0.04
0.020
0.03
0.015
Sr/Ca
Sr/Ca
Sr/Ca concentration in a spiked otolith
0.02
0.010
0.01
0.005
0.00
0.000
0
2
4
6
8
10
12
14
16
18
20
Distance across the otolith
22
24
26
28
30
0
2
4
6
8
10
12
14
16
18
Distance across the otolith
20
22
24
26
28
0.007
Sr/Ca concentration across the otolith
0.006
0.005
0.004
Sr/Ca
0.003
0.002
0.001
0.000
0
1
2
3
4
5
6
Date
7
8
9
10
11
12
Methods
• Fry will be marked with strontium, barium and
manganous chlorides.
• Using varied solution strengths and time duration.
• Chemical analyses will be done at the UAF Probe and
EM Lab.
• Elemental ratio we are concerned with are Sr/Ca
Ba/Ca, and Mg/Ca.
Importance
• Otolith chemistry techniques is being applied to
anadromous fish for the purpose of fisheries
management Gulkana Hatchery.
Overall Conclusion
• Through the application of otolith chemistry it will
be possible to develop management strategies that
target stocks and the conservation of their source
habitat.
Acknowledgements
•
•
•
•
•
•
•
•
•
Ken Severin
Nate Bickford
Ken Roberson
Denny Patnode
Luke Catledge
Mike Dansby
Douglas Dawson
Jane Flygstad
The students at UAF