Influence of ocean fronts on cetacean habitat selection and diversitywithin the CalCOFI study area

Dominique Camacho MAS, CMBC-Scripps Institution of Oceanography

Capstone Symposium – June 1, 2010

Photo: http://fascinatingly.com/

Explain fronts and cetacean Suborders

CalCOFI (California Cooperative Oceanic Fisheries Investigations)

Satellite Imagery : Thermal Front Analysis

Cetacean Sightings Linked to Front Activity

Conclusions

Applications

Outline

http://www.kiwifoto.com/images/galleryphotos/rissos_dolphin/rissos_dolphin_7C2V0697.jpg

What is a Thermal Front?

A boundary between 2 dissimilar water masses,characterized by a temperature gradient.

Value to Cetaceans?

Fronts increase surface nutrients that support primary and secondary productivity.

http://www.micrographia.com http://www.nmfs.noaa.gov/

CetaceansMysticeti : baleen Odonteceti : toothed

Gray whale

Humpback whale

Blue whale

Fin whale

Bottlenose dolphin

Risso’s dolphin

Killer Whale

Illustrations: Pieter Folkens Illustrations: Pieter Folkens

77

80

83

87

90

93

Obtaining Sighting Data Observations made during daylight hours• ship steaming between stations at ~10 knots

2 observers stationed port and starboard, scanning 90°• 7-power and 25-power binoculars

Photos: http://denisglennon.com/ and http://www.nmfs.noaa.gov/

Detecting Front ActivityAVHRR (Advanced Very High Resolution Radiometer) Pathfinder 5.0

• 4km resolution satellite images from NOAAs NESDIS

WIM (Windows Image Manager) – SIED (Single Image Edge Detection)

• Cayula and Cornillon, 1992

• Diehl et al. 2002

Linking Cetacean Presence to Fronts

ArcGIS 9.3

• Euclidean distance from sightings to thermal fronts

• Generated random points for comparison

Matlab 7.0

• 2 Sample Kolmogorov-Smirnov Test

Photo: D. Camacho

Summer

H=1

p=1.7386e-15

D=0.6233

n=44

Fall

H=1

p=1.5819e-15

D=0.4719

n=25

Winter

H=0

p=0.2915

D=0.1502

n=41 (39 Grays)

Spring

H=0

p=0.2853

D=0.1958

n=24

Mysticetes Distance to Fronts: 2 Sample K-S Test

0 20 40 60 80

Distance (km)

0 20 40 60 80 100 120 140

Distance (km)

0 50 100 150

Distance (km)

0 20 40 60

Distance (km)

Summer

H=1

p=1.6521e-16

D=0.4422

n=93

Fall

H=1

p=4.0765e-05

D=0.3142

n=53

Winter

H=1

p=2.8864e-04

D=0.2768

n=56

Spring

H=0

p=2.8864e-04

D=0.2768

n=56

Odontecetes Distance to Fronts: 2 Sample K-S Test

0 40 80 120

Distance (km)

0 40 80 120

Distance (km)

0 50 100 150

Distance (km)

0 40 80 120 160

Distance (km)

Species Specific Differences

Conclusions

• Seasonal differences in front activity

• Zone of high front activity located on the continental shelf

• Mysticetes are more tightly associated with fronts than odontecetes

• Variations within the major feeding types

Applications

Photo: Cascadia Research Collective

• Identify biologically important areas

• Predictive modeling

• Aid management / policy decisions

• Mitigate anthropogenic impacts

Modify shipping lane routes or identify speed reduction zones

Los Angeles

Point Conception

Courtesy of Megan McKennaMarch 10-13th2010 ship activitySource: Automatic Identification System (AIS)Note: Color represent direction of travel

Naval Mitigation:

optimal time windows for naval training exercises

http://upload.wikimedia.org/wikipedia/commons/f/fa/USS_Hayler_DD-997.jpg

Marine Protected Areas focused on cetaceans

Acknowlegments

I want to give a special thanks to my Committee Advisors John Hildebrand, Jay Barlow, and Karen Stocks for their encouragment and expertise. Mati Kahru for giving me his undivided WIM attention.

Tracey Hughs for her GIS knowledge. Megan McKenna for sharing her ASI data. To my program managers and classmates who offered a ear when I needed it. Most of all, my husband who listened to

me give this talk an ungodly number of times.

THANK YOU!

Questions?