Harbor Seals [ds106]

SDE Feature Class

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Tags
harbor seal, haul-out, mammal, coastal, Phoca vitulina, monitoring, population, biota, distribution, trend, abundance


Summary

The purpose of this project is to survey the abundance and distribution of harbor seals (Phoca vitulina richardsi) at all known haul-out sites in California coastal waters and offshore islands during the peak of the molt cycle.

Description

In May of 2001, the California Department of Fish and Game (CDFG) conducted an aerial photographic survey of the California coast and the offshore Channel Islands to obtain a minimum estimate of the population of harbor seals (Phoca vitulina richardsi) living in California. The developed photographs were examined to count the number of harbor seals present and determine the location of each haul-out site by comparison to photos taken in previous surveys. This survey was successful in obtaining nearly complete coverage of all known haul-out areas. The 1995 survey was the last complete coverage. The total county for 2001 is 12,312 harbor seals. This result is the lowest ever recorded by CDFG for a combined count of the mainland and all offshore islands. The California Department of Fish and Game (CDFG) conducted two surveys in 2002 in an attempt to provide better coverage and to lessen the chances of weather related problems. A total of 16 days were scheduled for aerial surveys from May 19 to July 19, 2002. Total count for Survey 1 was 10,541 harbor seals, while that for Survey 2 was 8,374 harbor seals. Camera problems that produced un-readable film and poor weather conditions prevented a complete assessment by either survey. The lack of complete coverage by either Survey 1 or 2 limited the total number of harbor seals counted. This is especially true in areas where past surveys revealed high concentrations of seals such as the northern Channel Islands and Point Reyes - Sonoma County coast. The California Department of Fish and Game (CDFG) conducted two aerial surveys in 2003 in an attempt to provide better coverage and to lessen the chances of weather related problems. A total of 20 days were scheduled for aerial surveys from May 25 to July 20, 2003. Complete coverage was achieved in both surveys. This was the first time CDFG conducted these surveys using a digital imaging camera. Total count for Survey 1 was 17,415, while that for Survey 2 was 17,778 harbor seals.

Credits

Use limitations

Extent

West -124.421528 East -117.275883
North 41.939340 South 32.815338

Scale Range

ArcGIS Metadata

Topics and Keywords

Themes or categories of the resource biota


* Content type Downloadable Data


Place keywords coastal

Theme keywords harbor seal, haul-out, mammal, Phoca vitulina, monitoring, population, biota, distribution, trend, abundance

Citation

* Title DS0106_20050518
Publication date 2005-01-01


Presentation formats * digital map


Citation Contacts

Responsible party
Organization's name California Department of Fish and Game
Contact's role originator


Resource Details

Dataset languages English(UNITED STATES)


Status completed
Spatial representation type * vector


Supplemental information
CDFG has monitored the numbers of harbor seals on the mainland coast of California, as well as offshore islands during the peak of their molting season since the early 1980s. Funding from the Pacific States Marine Fisheries Commission allowed CDFG to continue that effort. CDFG has used a single survey to census harbor seals along the California coastline and offshore islands since 1982. Because of unexpected low counts for the 2001 survey, a workshop was convened to review methodologies and to make recommendations for future surveys. The West Coast Harbor Seal Abundance Workshop was held March 28-29, 2002 at the NOAA/NMFS Southwest Fisheries Science Center in La Jolla (Barlow 2002). The workshop participants concluded that the 2001 survey was most likely scheduled too early and missed the peak molt period. Recommendations for the 2002 survey included: 1) splitting the survey into a southern California section (Channel Islands and the southern central coast to Point Sur) and a northern California section (the northern central coast and remainder of California north coast), 2) conducting the southern section in May or June and the northern section in July to more closely follow the peak molt period. 3) surveying the Channel Islands in the afternoon may be more important than tidal stage, and 4) conducting two surveys in an attempt to provide better coverage and to lessen the chances of weather related problems. The protocol used for this survey was essentially the same as that originally developed by Miller et al (1983), and last reported in Fluharty (1999). We have added our own improvements by taking advantage of new technology. The mainland coast as well as the Channel Islands were surveyed using the Department's twin engine, high wing Partenavia P68 "Observer ll" aircraft. This aircraft is equipped with a large photographic-observation port located in the floor of the aircraft behind the pilot's and copilot's seats. Use of this port enabled the photographer to locate and identify harbor seals and photograph them from directly overhead. The survey was conducted from an altitude of 600 to 700 feet, with an average altitude of 650 feet, depending on visibility and other conditions. In 2001 Color photographs were taken using a motor-driven Hasselblad 2003 FCW camera, Zeiss F3.5 100mm lens and large capacity film magazines containing 70mm Kodak E100S Ektachrome Professional film. In 2003 color digital images were taken using a Nikon D1x 6.3 Mg pixel computerized camera, Nikkor 28mm - 70 mm Auto-Focus lens, 1 Gb Compact Flash memory drives and "realtime" GPS interface from a Garmin 12XL portable unit (the Nikon digital system encoded all parameters of the exposure settings and time - geographic coordinates onto the digital image). The survey team consisted of a warden pilot, a data recorder and a photographer. Preliminary in-flight haul-out site identification was accomplished using a Garmin 12 channel portable GPS receiver pre-loaded with the coordinates of known haul-out sites, as well as topographic survey maps labeled with known sites. For 2001 harbor seals were identified and enumerated from processed photographs using a Nikon binocular dissecting microscope, 10x hand-held film viewer over a Bausch and Lomb "corrected" light table. Haul-out sites were positively identified by comparison with photographs taken in previous surveys and by position notes taken in-flight. For 2003 harbor seals were identified and enumerated from the images using Nikon "View" and "Edit" computer software. Some sites were positively identified by comparison with photographs taken in previous surveys. For 2001, the aerial photographic surveys were scheduled and flown on May 1, 2, and 3 for the Channel Islands, and on May 14-17 for the mainland. The mainland survey started at Point Mugu and finished at the Oregon border. All areas of San Francisco Bay and all major rivers and bay were covered. Approximately 30 miles of coastline north of Santa Cruz and just south of Half Moon Bay were not covered due to low lying coastal fog. We tried to re-survey that area later in the day, but the fog was still present. The mainland survey was completed in four days without further incident. Weather, visibility and tidal conditions were optimal over most of the survey period. Ground counts were obtained for Children's Pool and Seal Rock in La Jolla, San Diego County just prior to the mainland aerial survey. We requested and obtained ground counts for the Farallon Islands for the time period of the mainland survey. For 2002 the survey was conducted form May 19 through July 19. For 2003 the survey was conducted May 25 through July 20.
* Processing environment Microsoft Windows 7 Version 6.1 (Build 7601) Service Pack 1; Esri ArcGIS 10.1.1.3143


ArcGIS item properties
* Name DS0106_20050518
* Location Server=; :; Database=; User=; Version=
* Access protocol ArcSDE Connection

Extents

Extent
Description
ground condition
Temporal extent
Beginning date 2001-01-01
Ending date 2003-01-01

Extent
Geographic extent
Bounding rectangle
Extent type Extent used for searching
* West longitude -124.421528
* East longitude -117.275883
* North latitude 41.939340
* South latitude 32.815338
* Extent contains the resource Yes

Extent in the item's coordinate system
* West longitude -13850541.145400
* East longitude -13055091.540300
* South latitude 3870818.710000
* North latitude 5151897.145700
* Extent contains the resource Yes

Resource Points of Contact

Point of contact
Individual's name Robert B. Read
Organization's name California Department of Fish and Game, Marine Region
Contact's position Associate Biologist
Contact's role point of contact


Contact information
Phone
Voice 858 467-4213
Fax 858 467-4299

Address
Type both
Delivery point 4949 Viewridge Avenue
City San Diego
Administrative area CA
Postal code 92123
Country US
e-mail address rread@dfg.ca.gov



Resource Maintenance

Resource maintenance
Update frequency annually


Spatial Reference

ArcGIS coordinate system
* Type Projected
* Geographic coordinate reference GCS_WGS_1984
* Projection WGS_1984_Web_Mercator_Auxiliary_Sphere
* Coordinate reference details
Projected coordinate system
Well-known identifier 102100
X origin -20037700
Y origin -30241100
XY scale 10000
Z origin 0
Z scale 1
M origin 0
M scale 1
XY tolerance 0.001
Z tolerance 2
M tolerance 2
High precision true
Latest well-known identifier 3857
Well-known text PROJCS["WGS_1984_Web_Mercator_Auxiliary_Sphere",GEOGCS["GCS_WGS_1984",DATUM["D_WGS_1984",SPHEROID["WGS_1984",6378137.0,298.257223563]],PRIMEM["Greenwich",0.0],UNIT["Degree",0.0174532925199433]],PROJECTION["Mercator_Auxiliary_Sphere"],PARAMETER["False_Easting",0.0],PARAMETER["False_Northing",0.0],PARAMETER["Central_Meridian",0.0],PARAMETER["Standard_Parallel_1",0.0],PARAMETER["Auxiliary_Sphere_Type",0.0],UNIT["Meter",1.0],AUTHORITY["EPSG",3857]]

Reference system identifier
* Value 3857
* Codespace EPSG
* Version 7.11.2


Spatial Data Properties

Vector
* Level of topology for this dataset geometry only


Geometric objects
Feature class name DS0106_20050518
* Object type point
* Object count 1652



ArcGIS Feature Class Properties
Feature class name DS0106_20050518
* Feature type Simple
* Geometry type Point
* Has topology FALSE
* Feature count 1652
* Spatial index TRUE
* Linear referencing FALSE



Data Quality

Lineage

Process step
Description
The protocol used for this survey was essentially the same as that originally developed by Miller et al (1983), and last reported in Fluharty (1999). We have added improvements by taking advantage of new technology. The mainland coast and the Channel Islands were surveyed using the Department's twin engine, high-wing Partenavia P68 "Observer ll" aircraft. This aircraft is equipped with a large photographic-observation port located in the floor of the aircraft behind the pilot's and copilot's seats. Use of this port enabled the photographer to locate and identify harbor seals and photograph them from directly overhead. The survey was conducted from an altitude of 600 to 700 feet, with an average altitude of 650 feet, depending on visibility and other conditions. Color photographs were taken using a motor-driven Hasselblad 2003 FCW camera, Zeiss F3.5 100mm lens and large capacity film magazines containing 70mm Kodak E100S Ektachrome film. The survey team consisted of a warden pilot, a data recorder and a photographer. We employed a new computer-driven technology that provided an exact time and position for each release of the camera film advance trigger. This was accomplished using GSTRIG - Ground Speed Camera Trigger software by Compix on a DOS - based laptop computer connected to a channel GPS unit. A wireless remote sensor interfaced with the camera flash synch port and triggered another remote attached to the computer's I/O port. As a backup measure, the coordinates of known haul-out sites were pre-loaded into a GPS unit and we carried topographic maps labeled with known sites. Harbor seals were identified and enumerated from processed photographs using a Nikon binocular dissecting microscope, and 10x hand-held viewer over a Bausch and Lomb "corrected light" table. Haul-out sites identified in the film sequence were matched to their corresponding flight data file of time and position. Some sites were positively identified by comparison with photographs taken in previous surveys.




Geoprocessing history

Process
Process name Project_2
Date 2005-05-1811:42:33
Tool location C:\Program Files\ArcGIS\ArcToolbox\Toolboxes\Data Management Tools.tbx\Project
Command issued
Include in lineage when exporting metadata No


Process
Process name Append_3
Date 2005-05-1811:53:38
Tool location C:\Program Files\ArcGIS\ArcToolbox\Toolboxes\Data Management Tools.tbx\Append
Command issued
Include in lineage when exporting metadata No


Process
Date 2011-07-2108:33:59
Tool location C:\Program Files\ArcGIS\ArcToolbox\Toolboxes\Conversion Tools.tbx\FeatureClassToFeatureClass
Command issued
Include in lineage when exporting metadata No


Process
Date 2013-06-2114:15:30
Tool location c:\program files (x86)\arcgis\desktop10.1\ArcToolbox\Toolboxes\Data Management Tools.tbx\Project
Command issued
Include in lineage when exporting metadata No


Distribution

Distribution format
* Name SDE Feature Class


Transfer options
Online source
Location ftp://ftp.dfg.ca.gov/BDB/GIS/BIOS/Public_Datasets/100_199/ds106.zip

Online source
Location http://bios.dfg.ca.gov/

Fields

Details for object DS0106_20050518
* Type Feature Class
* Row count 1652


Field OBJECTID
* Alias OBJECTID
* Data type OID
* Width 4
* Precision 10
* Scale 0
* Field description
Internal feature number.
* Description source
ESRI
* Description of values
Sequential unique whole numbers that are automatically generated.




Field COUNTY
* Alias COUNTY
* Data type String
* Width 22
* Precision 0
* Scale 0
Field description
County


Field LOCATION
* Alias LOCATION
* Data type String
* Width 53
* Precision 0
* Scale 0
Field description
Name of island, or point of reference


Field SUBSTRATE
* Alias SUBSTRATE
* Data type String
* Width 66
* Precision 0
* Scale 0
Field description
Substrate types: onshore beach (sandy or rocky); estuary or mud flat, river or bay; extensive reef system (on or off shore); offshore rock or reef; onshore rock or reef


Field PHOTOCOUNT
* Alias PHOTOCOUNT
* Data type Double
* Width 8
* Precision 15
* Scale 0
Field description
Number of individuals counted in the photograph.


Field AERIAL_EST
* Alias AERIAL_EST
* Data type String
* Width 14
* Precision 0
* Scale 0
Field description
Number of individuals estimated while flying.


Field GRND_COUNT
* Alias GRND_COUNT
* Data type String
* Width 16
* Precision 0
* Scale 0
Field description
Number of individuals counted on the ground.


Field YEAR_
* Alias YEAR_
* Data type Double
* Width 8
* Precision 16
* Scale 0
Field description
Year of the record


Field DATE_
* Alias DATE_
* Data type Date
* Width 36
* Precision 0
* Scale 0
Field description
Date of the record


Field TIME
* Alias TIME
* Data type Double
* Width 8
* Precision 11
* Scale 0
Field description
Time of the record


Field FLIGHT_NO
* Alias FLIGHT_NO
* Data type Double
* Width 8
* Precision 13
* Scale 0
Field description
Flight number


Field LATDD
* Alias LATDD
* Data type Double
* Width 8
* Precision 19
* Scale 6
Field description
Latitude (in decimal degrees) in NAD27 (for data collected in 2001 and 2002) or WGS84 (for data collected in 2003)


Field LONDD
* Alias LONDD
* Data type Double
* Width 8
* Precision 19
* Scale 6
Field description
Longitude (in decimal degrees) in NAD27 (for data collected in 2001 and 2002) or WGS84 (for data collected in 2003)


Field SHAPE
* Alias Shape
* Data type Geometry
* Width 4
* Precision 0
* Scale 0
* Field description
Feature geometry.
* Description source
ESRI
* Description of values
Coordinates defining the features.






References

Aggregate Information
Association type cross reference


Aggregate resource name
Title Summary of Pacific Harbor Seal, Phoca vitulina richardsi, surveys in California, 1982 to 1995. CDFG-MR Admin. Rep 99 - 1.49 pp
Publication date 1999-01-01


Responsible party
Organization's name Fluharty, M.J. 1999
Contact's role originator




Metadata Details

Metadata language English(UNITED STATES)
Metadata character set utf8 - 8 bit UCS Transfer Format


Scope of the data described by the metadata dataset
Scope name * dataset


* Last update 2014-04-28


ArcGIS metadata properties
Metadata format ArcGIS1.0
Metadata style FGDC CSDGM Metadata


Created in ArcGIS for the item 2014-03-0615:21:33
Last modified in ArcGIS for the item 2014-04-2809:07:45


Automatic updates
Have been performed Yes
Last update 2014-04-2809:07:45


Metadata Contacts

Metadata contact
Individual's name Mark Lampinen
Organization's name California Department of Fish and Game, Office of Spill Prevention and Response
Contact's position Research Analyst (GIS)
Contact's role point of contact


Contact information
Phone
Voice 916 322-4777
Fax 916 324-8829

Address
Type both
Delivery point 1700 K Street
City Sacramento
Administrative area CA
Postal code 95814
Country US
e-mail address mlampinen@dfg.ca.gov



Thumbnail and Enclosures

Enclosure
Enclosure type File
Description of enclosure original metadata
Original metadata document, which was translated yes
Source metadata format fgdc