New Insights into Ancient Fish: Isotopes and Trace Elements Reveal

White Sturgeon Life History StrategiesJamie Sweeney, Malte Willmes, Kirsten Sellheim, & Joseph Merz

Email: jamie.sweeney@fishsciences.net

AFS & TWS Joint Conference

Reno, NV - October 3, 2019

White Sturgeon

© http://fieldguide.mt.gov

Western

Hemisphere

Range

▪ Vulnerable to over exploitation

▪ Limited life history information

▪ Better understanding = improved

population management

Why should we

care?

Image credit: NOAA Fisheries – Acoustic Telemetry

Image credit: Jasmine Shen – DWR Fyke trap

Image credit: Zac Jackson/Laura Hieronimus - USFWS egg mat

surveys

Monitoring Efforts

Hobson et al. 2010

▪ Useful tool to understand migratory patterns

▪ Some calcified structures in fish can incorporate

strontium signatures from the water they inhabit as

they grow

▪ Microchemistry is often used to reconstruct migratory

patterns of salmon using their otoliths (ear bones)

Graphic credit: Chris Donahoe

Adult (Ocean)

Juvenile

(fresh water)

Yolk Sac

(maternal)

Laser Ablation

transect

Microchemistry

Fin rays are calcified structures and collection is non-lethal

Cross-sectioned

adult fin ray

Microchemistry

Explore life history

strategies of CA adult

populations using fin

ray microchemistry

1. 2. Determine how early fin

rays develop and begin

recording life history

information

Study Objectives

1. Fin Ray

Microchemistry

▪116 wild fin rays

collected between

2012 - 2016

CA

San Francisco Estuary

San Joaquin River

1. Fin Ray

Microchemistry

Sample Processing and analysis:

Fin ray

removal

▪116 wild fin rays

collected between

2012 - 2016

CA

San Francisco Estuary

San Joaquin River

Sample Processing and analysis:

Fin ray

removal

Sectioned Fin Ray:

RED line marks laser

ablation transect and

age markers

1. Fin Ray

Microchemistry

▪116 wild fin rays

collected between

2012 - 2016

CA

San Francisco Estuary

San Joaquin River

Sample Processing and analysis:

Fin ray

removal

Sectioned Fin Ray:

RED line marks laser

ablation transect and

age markers

Interdisciplinary Center for

Plasma Mass Spectrometry

Laser ablation to

analyze strontium

ratios

1. Fin Ray

Microchemistry

▪116 wild fin rays

collected between

2012 - 2016

CA

San Francisco Estuary

San Joaquin River

Life History Diversity

Distance from core to edge of fin ray

87S

r/86S

r

Freshwater

Low Salinity

Polysaline

High Salinity

1. Fin Ray

Microchemistry

Several years in low salinity, followed by

migration into high salinity after Year 7

Early migration into high salinity, return

to freshwater/low salinity after Year 3

Life History Diversity

1. Fin Ray

Microchemistry

Primarily low salinity/fresh water

Primarily high salinity

Life History Diversity

1. Fin Ray

Microchemistry

San Joaquin Sturgeon

1. Fin Ray

Microchemistry

Acoustic telemetry detections in San Joaquin River

Age 0 – 5 Habitat Use

High Salinity

1. Fin Ray

Microchemistry

Age 0 – 5 Habitat Use

High Salinity

1. Fin Ray

Microchemistry

2. Early Fin Ray

Development

▪ When do fin rays begin to calcify?

▪ How early can fin rays uptake trace

elements from their environment?

▪ 20 fish collected bi-

weekly from 12 days post

hatch (dph) to 76 dph

2. Early Fin Ray

Development

No Calcification Start of Calcification Calcification

Fish TL :

24 mm

Measured

calcification

length

Extent

possible

calcification

length

2. Early Fin Ray

Development

Fish TL :

27 mmFish TL :

35 mm

▪When do fin rays begin to calcify?

(Clear and Stain - left pectoral fins)

No Calcification Start of Calcification Calcification

Fish TL :

24 mm

2. Early Fin Ray

Development

Fish TL :

27 mmFish TL :

35 mm

Measured

calcification

length

Extent

possible

calcification

length

▪When do fin rays begin to calcify?

(Clear and Stain - left pectoral fins)

No Calcification Start of Calcification Calcification

Fish TL :

24 mm

2. Early Fin Ray

Development

Fish TL :

27 mmFish TL :

35 mm

Measured

calcification

length

Extent

possible

calcification

length

▪When do fin rays begin to calcify?

(Clear and Stain - left pectoral fins)

No Calcification Start of Calcification Calcification

Fish TL :

24 mm

2. Early Fin Ray

Development

Fish TL :

27 mmFish TL :

35 mm

Measured

calcification

length

Extent

possible

calcification

length

▪When do fin rays begin to calcify?

(Clear and Stain - left pectoral fins)

2. Early Fin Ray

Development

AGE (dph)

TL (mm)

≥ 95% calcified by ≥ 72 dph

50% calcified by 32 dph

≥ 95% calcified by ≥ 70 mm

50% calcified by 39 mm

2. Early Fin Ray

Development

AGE (dph)

TL (mm)

≥ 95% calcified by ≥ 72 dph

50% calcified by 32 dph

≥ 95% calcified by ≥ 70 mm

50% calcified by 39 mm

2. Early Fin Ray

Development

▪When do fin rays begin to calcify?

(Laser Ablation - right pectoral fins)

2. Early Fin Ray

Development

No fin ray calcium detected in fish ≤ 28 mm TL or ≤ 26 dph

43C

aco

nc

en

trati

on

s (

CP

S)

Distance across each fin ray (µm)

2. Early Fin Ray

Development

Fin ray calcium detected in fish as early as 30 mm TL and 30 dph

Distance across each fin ray (µm)43C

aco

nc

en

trati

on

s (

CP

S)

2. Early Fin Ray

Development

Calcium detections in fish between 48 mm - 112 mm (44 - 76 dph)

Distance across each fin ray (µm)43C

aco

nc

en

trati

on

s (

CP

S)

2. Early Fin Ray

Development

▪How early can fin rays uptake trace elements from

their environment?

Trace element concentrations in fin rays compared to water

2. Early Fin Ray

Development

Sr

Ba

Mg

Ele

me

nt

Co

nc

en

tra

tio

ns (

pp

m)

Fin ray Water

Trace element concentrations in fin rays compared to water

2. Early Fin Ray

Development

Sr

Ba

Mg

Ele

me

nt

Co

nc

en

tra

tio

ns (

pp

m)

Fin ray Water

U

Pb

Summary

▪ Diverse adult life history strategies

▪ No detectable calcification before 30 days (30 mm)

▪ Juvenile fin rays incorporate trace elements

▪ Increase adult sample size

▪Explore Oxygen Isotopes

▪Environmental effects on

development and life

history strategies

Future Directions

UC Davis

• CABA Research Facility

• Fangue lab - Nann Fangue, Dennis Cocherell,

Sarah Baird, Fangue Lab staff

• Joseph J. Cech

• Todgeham lab - Todgeham lab staff

• ICPMS lab(s) – Justin Glessner, Howie Spero

• Hobbs lab – Jim Hobbs, Levi Lewis

• Wainwright lab – Peter Wainwright, Max Rupp

UC Santa Cruz/Cornell University

• Liam Zarri

U.S Fish and Wildlife Services

• Paul Cadrett, Laura Heironimus, Zac

Jackson and USFWS field crew

Cramer Fish Sciences

• Katie Karpenko, Tyler Goodearly, Jasmine Shen

University of Idaho

• Shannon Blackburn, Michael Quist

Acknowledgements

Questions?

© Art - Lance Marshall Boen

Life History Diversity Patterns

1. Fin Ray

Microchemistry