Identifying Biological Hot Spots in the Northern California Current · Background • Logical starting point – Begin by identifying where hot spots occur • Also need to know:

Identifying Biological Hot Spots in Identifying Biological Hot Spots in the Northern California Currentthe Northern California Current

Douglas C. ReeseDouglas C. ReeseCollege of Oceanic and Atmospheric Sciences, Oregon State UniverCollege of Oceanic and Atmospheric Sciences, Oregon State Universitysity

Richard D. BrodeurRichard D. BrodeurNorthwest Fisheries Science Center, NOAA Hatfield Marine ScienceNorthwest Fisheries Science Center, NOAA Hatfield Marine Science CenterCenter

BackgroundBackground

•• Logical starting pointLogical starting point–– Begin by identifying where hot spots occurBegin by identifying where hot spots occur

•• Also need to know:Also need to know:–– How persistent they areHow persistent they are–– Community characteristicsCommunity characteristics

•• Community composition, dominant species, biodiversity, Community composition, dominant species, biodiversity, etc.etc.

–– Driving forces that structure these areasDriving forces that structure these areas

Current understandingCurrent understanding

• Species diversity and dominance of surface zooplankton and coastal pelagic nekton have been determined to vary between geographic regions

• Species assemblages have been shown to vary both with distance from shore and latitude

• California Current ecosystem has undergone dramatic shifts in abundance and species composition at both the lower and higher trophic levels

Objectives of the StudyObjectives of the Study

• Identify regions of high levels of phytoplankton and surface zooplankton productivity

• Identify regions of persistent high levels of surface zooplankton and nekton biodiversity

• Identify dominant members and the structure of the nektonic communities within these regions

• Examine the habitat characteristics associated within these areas

Study RegionStudy Region

Study RegionStudy Region

Heceta Bank

Cape Blanco

Data CollectionData Collection

• Sampling was conducted during a 2 week period in June and August of 2000 and 2002 as part of the U.S. GLOBEC mesoscale surveys

• Stations were sampled along both regular transects and also in areas of special biological interest

• At each station a CTD cast, neuston tow and pelagic surface trawl were made and a chlorophyll sample collected

Identifying Biological ActivityIdentifying Biological Activity

• Several biological parameters examined:– Chlorophyll concentrations– Surface zooplankton biovolume and diversity – Nekton abundance– Nekton species diversity– Nekton biomass

• Hot spot = An area with greater than average biological activity in terms of nekton density, species richness, and/or biomass

Identifying Hot SpotsIdentifying Hot Spots

• Geostatistical modeling techniques– Designed to model spatially dependent data by incorporating

spatial autocorrelation

• Optimally predict values at intermediate sites

• Assess error associated with predictions

• Geostatistics vs. classical methods– When accounting for spatial autocorrelation, conclusions

about environmental control over distribution and abundance changed dramatically

• Although our data are not synoptic, maps of temperature and chlorophyll closely match with satellite imagery

Statistical ProceduresStatistical Procedures

• Group differences in species composition between hot spots and non-hot spots were tested with a multi-response permutation procedure (MRPP)

• Ordination of the sample stations in species space was done using non-metric multidimensional scaling (NMS) using the geographic location of hot spots as a categorical variable

• Correlations of environmental variables with each axis were used to measure the relationships of these variables to species data

• Identification of the primary species for each hot spot was done using indicator species analysis (ISA)

ZooplanktonChlorophyll

June 2000June 2000

Nekton Density Nekton Biomass Nekton Species Richness

Chlorophyll Zooplankton

August 2000August 2000

Nekton BiomassNekton Density Nekton Species Richness

ZooplanktonChlorophyll

June 2002June 2002


Chlorophyll Zooplankton

August 2002August 2002


Hot SpotsHot Spots

June 2000Hotspots

August 2000Hotspots

June 2002Hotspots

August 2002Hotspots

MRPP ResultsMRPP Results

CruiseCruiseChanceChance--corrected withincorrected within--

group agreement, group agreement, AA pp--valuevalue

June 2000June 2000 0.14800.1480 <0.0001<0.0001

August 2000August 2000 0.17480.1748 <0.0001<0.0001

June 2002June 2002 0.07890.0789 0.00010.0001

August 2002August 2002 0.09470.0947 <0.0001<0.0001

H0: No difference in community composition between hot spots and no hot spots

Results indicate significant differences for each cruise

NMS OrdinationsNMS OrdinationsJune 2000 August 2000

10A-1

10A-2

11A-1

11A-2

11A-3

11B-1

11B-2

11B-3

11B-4

2A-1

2A-2

2A-3

2A-5

2A-6

2A-7

4A-1

6B-1

6B-2

6B-37AA-1

7AA-2

7AA-3

8A-1

9-1

9-2

9-3

9A-1

9A-2

9A-3

9A-4

CR-1

CR-2

CR-3

CR-4

FM-3

FM-4

FM-5

FM-6

FM-7

FM-8

HH-0

HH-1A

HH-2

HH-3

HH-4

HH-4A

HH-5

NH-10

NH-15

NH-20

NH-25NH-5

RR-1

RR-2

RR-4

RR-5

RR-6

RR-7UR-1

UR-2UR-3

UR-4UR-5

UR-6

UR-7

UR-8

DepthSalTempDens

June 2000

Axis 1

Axis 3

HotspotNo HotspotHotspot NorthHotspot South

Stress = 19.65

2-1

2-2

2-3

2-4

2-5

2-6

7A-1

7A-2

7A-3

8-1

8-2

8-3

8A-1

8A-2

8B-1

8B-2

9-1

9-3

Birds-1

BOB-1

BOB-1A

BOB-2BOB-3

BOB-4

BOB-5

CR-1

CR-10

CR-11

CR-2

CR-3

CR-4

CR-6

CR-7

CR-8

CR-9

FM-1

FM-3HH-1

HH-1AHH-2

HH-3

HH-4

HH-5NFS-2

NFS-8

NFS-9

NH-10

NH-15

NH-20NH-25

NH-3NH-5

RR-1

RR-2

RR-4

RR-5RR-6

RR-7

UR-1

UR-3

UR-5

UR-7

UR-8

Depth

Sal

Temp

Dens

August 2000

Axis 2

Axis 3

HotspotsNo HotspotHotspot NorthHotspot South

Stress = 20.59

R2 = 0.621 for 3-D ordinationAxis 2: R2 = 0.197Axis 3: R2 = 0.257Temp r = 0.625

R2 = 0.653 for 3-D ordinationAxis 1: R2 = 0.254Axis 3: R2 = 0.230Temp r = 0.752

NMS OrdinationsNMS OrdinationsJune 2002 August 2002

1A-1

1A-2

1A-3

2A-2

3A-1

3A-2

4A-1

4A-2

6-1

6-2

6-3

6-4

7A-1

8-18-28-3 8-4

8-5

8-7

8-9

9-1

9-2

9-3

9B-1

9B-2

9B-3BOB-1

BOB-3

CR-1A

CR-2A

CR-3

CR-4

CR-5

FM-1

FM-3FM-4

FM-5

FM-6

FM-7FM-8

FM-9

HH-0A

HH-1A HH-2A

HH-3A

HH-4A

HH-5A

NH-10

NH-15

NH-20 NH-25

NH-35

NH-45

NH-5

RR-1

RR-2

RR-4RR-5

RR-6

RR-7

UR-0 UR-1

UR-2

UR-3

UR-4

UR-5UR-6DepthChla

June 2002

Axis 2

Axis 3


Stress = 17.65

11-311-4

11-5

11-6

1A-1

1A-2

1A-3

2-1

2-2

2-4

2A-1

2A-2

2A-33A-4

3A-5

4A-44A-5

4A-6

6-2

6-3

6-4

6-5

7A-27A-3

7A-4

7A-5

8-18-2

8-4

8-6

8-9

9-2

9-3

9-4

BOB-1

BOB-3BOB-4

BOB-5

CR-1

CR-2

CR-3CR-4

CR-5

CR-7

FM-1

FM-3

FM-5

FM-6 FM-7

FM-8

HH-1

HH-2HH-3HH-4

HH-5

HH-6HH-7

NH-10

NH-15

NH-20

NH-5

RR-1

RR-5

RR-6

RR-7

UR-2

UR-3

UR-4

UR-5

UR-6

UR-7DepthTemp

Dens

C4 NMS Results

Axis 2

Axis 3


August 2002

Stress = 19.31

R2 = 0.707 for 3-D ordinationAxis 2: R2 = 0.327Axis 3: R2 = 0.209Temp r = -0.438

R2 = 0.757 for 3-D ordinationAxis 2: R2 = 0.424Axis 3: R2 = 0.225

Chl r = -0.475Temp r = 0.385

Indicator Species AnalysisIndicator Species Analysis

Hot Spot North Hot Spot South No Hot Spot

June 2000 Bocaccio juvCabezon juvDover sole larvaePacific clubhook squidSeveral rockfish spp juv

Chinook subad & adultSteelhead juvMarket squidPacific herring adultSurf smelt adultWhitebait smelt juv

No significantIndicator Species

August 2000 Coho subad & adultCoho yearlingJack mackerel adultPacific mackerel adultPacific sardine adult

Chinook subad & adultChinook subyearlingChinook yearlingSteelhead juvMedusafish adultSurf smelt adultWolf eel juv

No significant Indicator Species

June 2002 Chinook yearlingCoho yearlingPacific sanddab adult

Rex sole larvaeRockfish juvWolf eel juv


August 2002 Northern Anchovy adult King-of-the-Salmon juvPacific herring adultRagfish juvSurf smelt adult


Habitat Comparisons Between Hot Spot RegionsHabitat Comparisons Between Hot Spot Regions

30.0

30.5

31.0

31.5

32.0

32.5

33.0

33.5

34.0

Jun-00 Aug-00 Jun-02 Aug-02

Cruise Date

Salin

ity

6.0

7.0

8.0

9.0

10.0

11.0

12.0

13.0

14.0

Jun-00 Aug-00 Jun-02 Aug-02Cruise Date

Tem

pera

ture

(C)

Hot Spot NorthHot Spot SouthNo Hot Spot

22.0

22.5

23.0

23.5

24.0

24.5

25.0

25.5

26.0

26.5


Cruise Date

Den

sity

0

2

4

6

8

10

12

14

16

18


Cruise Date

Chl

orop

hyll

a (u

g/l)

Nekton Comparisons Between Hot Spot RegionsNekton Comparisons Between Hot Spot Regions

Nekton Density (#/km^3)

0

500,000

1,000,000

1,500,000

2,000,000

2,500,000

3,000,000

3,500,000

4,000,000


Cruise Date

Nek

ton

Den

sity

Hot Spot NorthHot Spot SouthNo Hot Spot

Nekton Species Richness

0.0

1.0

2.0

3.0

4.0

5.0

6.0

7.0

8.0


Cruise Date

Nek

ton

Spec

ies R

ichn

ess

Results Results –– Dominant Members of Hot SpotsDominant Members of Hot Spots

•• Indicator Species AnalysisIndicator Species Analysis–– Most common member of northern hot spotMost common member of northern hot spot

•• Coho yearlingsCoho yearlings

–– Most common members of southern hot spotMost common members of southern hot spot•• Chinook Chinook subadultssubadults and adultsand adults•• Surf smelt adultsSurf smelt adults•• Pacific herring adultsPacific herring adults

•• Northern hot spot more important to young nektonNorthern hot spot more important to young nekton•• Southern hot spot species tended to be adultsSouthern hot spot species tended to be adults

ConclusionsConclusions

•• General locations of hot spots in north and south were General locations of hot spots in north and south were persistent across seasons and yearspersistent across seasons and years

•• Size of hot spots varied seasonally and annuallySize of hot spots varied seasonally and annually

•• Communities within hot spots varied seasonally and Communities within hot spots varied seasonally and annuallyannually

•• Temp, salinity, density, and depth were significant Temp, salinity, density, and depth were significant parameters explaining different communities in north and parameters explaining different communities in north and south hot spots especially in 2000, but was not as clear in south hot spots especially in 2000, but was not as clear in 20022002

•• None of the environmental variables examined seemed to None of the environmental variables examined seemed to reliably indicate the presence or lack of a hot spotreliably indicate the presence or lack of a hot spot

AcknowledgementsAcknowledgements

•• For field work and technical assistanceFor field work and technical assistance–– Bob EmmettBob Emmett–– Todd MillerTodd Miller–– Suzan PoolSuzan Pool–– Paul BentleyPaul Bentley–– Joe FisherJoe Fisher–– Bruce McCuneBruce McCune

•• Funding sourcesFunding sources–– U.S. GLOBEC ProgramU.S. GLOBEC Program–– NMFS, Northwest Fisheries Science CenterNMFS, Northwest Fisheries Science Center

Documents

Identifying Biological Hot Spots in the Northern California Current · Background • Logical starting point – Begin by identifying where hot spots occur • Also need to know: