OCS Study 

•

MMS 2003-012 

Aerial Surveys of Distribution and 

Abundance of Marine Birds and 

Mammals in Santa Barbara Channel 

and the Santa Maria Basin 

Final Technical Summary 

Final Study Report 

U.S. Department of the Interior 

Minerals Management Service

Pacific OCS Region 

Aerial Surveys of Distribution and 

Abundance of Marine Birds and 

Mammals in Santa Barbara Channel 

and the Santa Maria Basin 

Final Technical Summary 

Final Study Report 

Authors 

Russell J. Schmitt 

Michael L. Bonnell 

Principal Investigators 

Prepared under MMS Cooperative 

Agreement No. 14-35-0001-30758 

by 

Coastal Marine Institute 

Marine Science Institute 

University of California 

Santa Barbara, CA 93106 

U.S. Department of the Interior 

Minerals Management Service Camarillo

Pacific OCS Region March 2003
Disclaimer 

This report has been reviewed by the Pacific Outer Continental Shelf Region, Minerals Management 

Service, U.S. Department of the Interior and approved for publication. The opinions, findings, 

conclusions, or recommendations in this report are those of the authors, and do not necessarily reflect 

the views and policies of the Minerals Management Service. Mention of trade names or commercial 

products does not constitute an endorsement or recommendation for use. This report has not been 

edited for conformity with Minerals Management Service editorial standards. 

Availability of Report

Extra copies of the report may be obtained from: 

U.S. Dept. of the Interior 

Minerals Management Service 

Pacific OCS Region 

770 Paseo Camarillo 

Camarillo, CA 93010 

Phone: 805-389-7621 

A PDF file of this report is available at: 

http://www.coastalresearchcenter.ucsb.edu/CMI/ 

Suggested Citation 

The suggested citation for this report is: 

Schmitt, Russell J. and Bonnell, Michael L. Aerial Surveys of Distribution and Abundance of Marine 

Birds and Mammals in Santa Barbara Channel and the Santa Maria Basin. MMS OCS Study 2003-

012. Coastal Research Center, Marine Science Institute, University of California, Santa Barbara, 

California. MMS Cooperative Agreement Number 14-35-0001-30758. 23 pages. 
1

Table of Contents 

FINAL TECHNICAL SUMMARY 1 

FINAL STUDY REPORT 3 

Assessment of Historical Data for Sampling 

Design of the MMS Seabird Study 3 

 Introduction 4 

 Methods 6 

 Results and Discussion 6 

 Conclusions and Recommendations 14 

 Literature Cited 15 

Seasonal Abundance and Distribution of Coastal Seabirds 

Offshore Santa Barbara and Ventura Counties, California 16 

 Abstract 16 

 Introduction 16 

 Materials and Methods 16 

 Results 17 

 Discussion 20 

 Acknowledgements 21 

 Literature Cited 21 

Acknowledgements 23 
2

Assessment of Historical Data for Sampling Design of the MMS Seabird Study 

List of Tables 

Table 1. Mean density of all alcids in Santa Maria Basin area, 1980-1983. 9 

Table 2. Mean density of grebes, loons, scoters in Santa Maria Basin area, 1980-1983. 9 

Table 3. Mean density of cormorants and pelicans in Santa Maria Basin area, 1980-1983. 10 

Table 4. Number of sightings of prominent groups of marine birds in the Santa Maria 

Basin area, 1980-1983. 13 

List of Figures 

Figure 1. Existing Survey design for the MMS Seabird Study in the Santa Barbara 

Channel and the Santa Maria Basin. 5 

Figure 2. Mean monthly density of alcids in the Santa Maria Basin area, 1980-1983. 6 

Figure 3. Mean monthly density of grebes, loons, scoters in Santa Maria 

Basin area, 1980-1983. 8 

Figure 4. Mean monthly density of cormorants and pelicans in Santa Maria 

Basin area, 1980-1983. 8 

Figure 5. Mean monthly density, 1980-1983, of three groups of birds in the 

Santa Maria Basin area. 10 

Figure 6 (a). Density (animals/km2

) of alcids for the months of July through October. 11 

Figure 6 (b). Density (animals/km2

) of alcids for the months of January through March. 11 

Figure 7. Density (animals/km2

) of loons, grebes, and scoters for the months of 

October through April. 12 

Figure 8. Density (animals/km2

) of cormorants and pelicans for the months of 

October through April. 12 

Seasonal Abundance and Distribution of Coastal Seabirds Offshore Santa Barbara and 

Ventura Counties, California 

List of Tables 

Table 1. MMS Coastal Seabird/Marine Mammal Aerial Surveys 17 

Table 2. At-sea population estimates for coastal seabirds 18 

 

List of Figures 

Figure 1. Study area and standard aerial transect lines 17 

Figure 2. Western grebe densities (number/km2

), September to March 18 

Figure 3. Western grebe densities (number/km2

), April to August 18 

Figure 4. Scoter densities (number/km2

), September to March 19 

Figure 5. Scoter densities (number/km2

), April to August 19 

Figure 6. Cormorant densities (number/km2

), all months 19 

Figure 7. Loon densities (number/km2

), September to March 19 

Figure 8. Loon densities (number/km2

), April to August 20 

Figure 9. Brown pelican densities (number/km2

), February to May 20 

Figure 10. Brown pelican densities (number/km2

), June to January 20 
Aerial Surveys of Distribution and Abundance of Marine Birds and Mammals 

1

FINAL TECHNICAL SUMMARY 

STUDY TITLE: Aerial Surveys of Distribution and Abundance of Marine Birds and Mammals 

in Santa Barbara Channel and the Santa Maria Basin 

REPORT TITLE: Aerial Surveys of Distribution and Abundance of Marine Birds and 

Mammals in Santa Barbara Channel and the Santa Maria Basin 

CONTRACT NUMBER: 14-35-0001-30758 

SPONSORING OCS REGION: Pacific 

APPLICABLE PLANNING AREA: Southern California 

FISCAL YEARS OF PROJECT FUNDING: FY 96, FY 97 

COMPLETION DATE OF THE REPORT: September 1998 

COSTS: FY 96 - $22,261, FY 97 – $24,739 

CUMULATIVE PROJECT COST: $47,000

PROJECT MANAGER: Russell J. Schmitt 

AFFILIATION: University of California, Santa Barbara 

ADDRESS: Coastal Research Center, Marine Science Institute, University of California, Santa 

Barbara, CA 93106 

PRINCIPAL INVESTIGATORS: 1

Russell J. Schmitt, 2Michael L. Bonnell (deceased) 

ADDRESSES: 1 Coastal Research Center, Marine Science Institute, University of California, 

Santa Barbara, CA 93106; 2Institute of Ocean Sciences, University of California, Santa Cruz, 

CA 95064

BACKGROUND: In November of 1994 an ambitious project was undertaken to provide 

detailed mapping of abundance and distribution of seabirds and marine mammals in the Santa 

Barbara Channel and the Santa Maria Basin (Pacific OCS Region). Our task was to separate the 

background noise from the significant patterns of use of the more than 100 species that occupy 

these waters. This series of bi-monthly aerial surveys was supported by the Marine Science 

Institute (MSI), UCSB, and the California Department of Fish and Game, Office of Spill 

Prevention and Response (OSPR). OSPR provided matching funds in the form of aircraft 

services and this work served their needs as well as the Minerals Management Service (MMS). 

OBJECTIVES: Surveys continued through 1998 to gather additional data for geographical 

stratification of this area of development, abandonment, seismic profiling, and vessel traffic. 
Final Technical Summary – Schmitt and Bonnell 

2

Stratification was based on an analysis of variance for the many species of birds that nest, roost, 

or migrate through this area. Regions with the highest variance received the greatest effort on 

surveys; regions with the lowest variance (i.e., most predictable patterns of use) received less 

effort. 

 

DESCRIPTION AND RESULTS: Aerial Surveys were flown in a high-wing, twin-engine 

Partenavia PN68 Observer aircraft supplied by the CDFG Department of Air Services. The 

navigation was by GPS (Global Positioning System) with time/position entries into a computer at 

approximately eight-second intervals. The computer operator also entered important sightings 

(flocks of birds, marine mammals, water-mass boundaries, sea state, etc.) as well as number of 

observer(s) on watch. Typically only the observer on the shaded side of the aircraft was on duty; 

however, on northbound transects both observers were on watch searching a 50-meter corridor (a 

strip-census), with incidental sightings along the shore or outside the clinometer-defined search 

corridor noted. Sightings were recorded on voice-tape and later transcribed for computer entry 

by observation/time by the MMS. Time was then used to determine the position of sightings by 

melding the sighting file with the GPS record of time and latitude/longitude of the aircraft. All 

transects were flown at 200-feet (60-meters) altitude. To collect data on especially interesting 

sightings (e.g., flocks of birds near fishing boats, large whales, etc.), the aircraft increased 

altitude to approximately 600 ft. 

From the beginning of this project, a total of 38 surveys were conducted (exclusive of commutes) 

in 130 hours in the air. Transects thus far include nearly 15,700 km (8,631 nautical miles) 

making this the most effort-intensive study conducted in any MMS-OCS Region. The prospects 

of this study are exciting; the last time systematic surveys were conducted in the Santa Barbara 

Channel and Santa Maria Basin was more than a decade ago. 

SIGNIFICANT CONCLUSIONS: Over 50,000 sightings have been recorded, representing 

several hundred-thousand birds ─ this within a search swath of, at most, 100 meters. The 

numbers are astounding, in and of themselves, but we have also noted some remarkable findings 

─ sightings of alcids (auklets and murrelets) appear sparse, numbers of gulls and pelicans seem 

stable, multiple observations of common dolphins are stable but expanding within their range, 

and large numbers of blue whales and humpback whales are clearly occupying the outer Santa 

Barbara Channel and Santa Maria Basin in mating/migration season. 

STUDY PRODUCTS: 

Bonnell, M. L. and R. G. Ford. 1996. Assessment of historical data for sampling design of the 

MMS seabird study. Prepared for Minerals Management Service, Pacific OCS Region, 

Camarillo, California, by Ecological Consulting, Inc., Portland, OR. 16 pp. 

Pierson, Mark O., Michael D. McCrary, and Michael L. Bonnell. 1999. Seasonal Abundance 

and Distribution of Coastal Seabirds Offshore Santa Barbara and Ventura Counties, 

California. Fifth California Islands Symposium, OCS Study, MMS 99-0038: 428-434. 
Aerial Surveys of Distribution and Abundance of Marine Birds and Mammals 

3

FINAL STUDY REPORT 

 
Final Study Report – Schmitt and Bonnell 

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Aerial Surveys of Distribution and Abundance of Marine Birds and Mammals 

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Figure 1. Existing Survey design for the MMS Seabird Study in the Santa Barbara Channel and the Santa Maria 

Basin. 
Final Study Report – Schmitt and Bonnell 

6
Aerial Surveys of Distribution and Abundance of Marine Birds and Mammals 

7

Figure 2. Mean monthly density of alcids in the Santa Maria Basin area, 1980-1983. 
Final Study Report – Schmitt and Bonnell 

8

Figure 3. Mean monthly density of grebes, loons, scoters in Santa Maria Basin area, 1980-1983. 

Figure 4. Mean monthly density of cormorants and pelicans in Santa Maria Basin area, 1980-1983. 
Aerial Surveys of Distribution and Abundance of Marine Birds and Mammals 

9

Table 1. Mean density of all alcids in Santa Maria Basin area, 1980-1983. 

Table 2. Mean density of grebes, loons, scoters in Santa Maria Basin area, 1980-1983. 
Final Study Report – Schmitt and Bonnell 

10

Table 3. Mean density of cormorants and pelicans in Santa Maria Basin area, 1980-1983. 

Figure 5. Mean monthly density, 1980-1983, of three groups of birds in the Santa Maria Basin area. 
Aerial Surveys of Distribution and Abundance of Marine Birds and Mammals 

11

Figure 6 (a). Density (animals/km2

) of alcids for the months of July through October, averaged over the three years 

of available data. Data were binned into 15 minute blocks for contouring. 

Figure 6 (b). Density (animals/km2

) of alcids for the months of January through March, averaged over the three 

years of available data. Data were binned into 15 minute blocks for contouring. 
Final Study Report – Schmitt and Bonnell 

12

Figure 7. Density (animals/km2

) of loons, grebes, and scoters for the months of October through April, averaged 

over the three years of available data. Data were binned into 15 minute blocks for contouring. 

Figure 8. Density (animals/km2

) of cormorants and pelicans for the months of October through April, averaged 

over the three years of available data. Data were binned into 15 minute blocks for contouring. 
Aerial Surveys of Distribution and Abundance of Marine Birds and Mammals 

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Table 4. Number of sightings of prominent groups of marine birds in the Santa Maria Basin area, 1980-1983. 
Final Study Report – Schmitt and Bonnell 

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Aerial Surveys of Distribution and Abundance of Marine Birds and Mammals 

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Final Study Report – Schmitt and Bonnell 

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Aerial Surveys of Distribution and Abundance of Marine Birds and Mammals 

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Final Study Report – Schmitt and Bonnell 

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Aerial Surveys of Distribution and Abundance of Marine Birds and Mammals 

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Final Study Report – Schmitt and Bonnell 

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Aerial Surveys of Distribution and Abundance of Marine Birds and Mammals 

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Final Study Report – Schmitt and Bonnell 

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Aerial Surveys of Distribution and Abundance of Marine Birds and Mammals 

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ACKNOWLEDGEMENTS

Michael McCrary and Dr. Mark Pierson were the major observers on most surveys and deserve a 

sincere debt of gratitude, as does the MSI at UCSB, Bonnie Williamson for her able 

administration, Ed Cassano for a permit to work within nearshore waters of the Channel Islands 

National Marine Sanctuary, and OSPR for their continued support. It is not often that such a 

long-term project receives such sustained funding. My thanks to all. 
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The Department of the Interior Mission 

As the Nation's principal conservation agency, the Department of the Interior has responsibility for most 

of our nationally owned public lands and natural resources. This includes fostering sound use of our 

land and water resources; protecting our fish, wildlife, and biological diversity; preserving the 

environmental and cultural values of our national parks and historical places; and providing for the 

enjoyment of life through outdoor recreation. The Department assesses our energy and mineral 

resources and works to ensure that their development is in the best interests of all our people by 

encouraging stewardship and citizen participation in their care. The Department also has a major 

responsibility for American Indian reservation communities and for people who live in island territories 

under U.S. administration. 

The Minerals Management Service Mission 

As a bureau of the Department of the Interior, the Minerals Management Service's (MMS) primary 

responsibilities are to manage the mineral resources located on the Nation's Outer Continental Shelf 

(OCS), collect revenue from the Federal OCS and onshore Federal and Indian lands, and distribute 

those revenues. 

Moreover, in working to meet its responsibilities, the Offshore Minerals Management Program

administers the OCS competitive leasing program and oversees the safe and environmentally sound 

exploration and production of our Nation's offshore natural gas, oil and other mineral resources. The 

MMS Royalty Management Program meets its responsibilities by ensuring the efficient, timely and 

accurate collection and disbursement of revenue from mineral leasing and production due to Indian 

tribes and allottees, States and the U.S. Treasury. 

The MMS strives to fulfill its responsibilities through the general guiding principles of: (1) being 

responsive to the public's concerns and interests by maintaining a dialogue with all potentially affected 

parties and (2) carrying out its programs with an emphasis on working to enhance the quality of life for 

all Americans by lending MMS assistance and expertise to economic development and environmental 

protection.