GAP: Feeding and seasonality of gray whales in Ugak Bay; Kodiak Island Alaska

Transcription

1 GAP: Feeding and seasonality of gray whales in Ugak Bay; Kodiak Island Alaska Metadata: Identification_Information Data_Quality_Information Entity_and_Attribute_Information Distribution_Information Metadata_Reference_Information Identification_Information: Citation: Citation_Information: Description: Originator: Briana H. Witteveen Originator: Kate M. Wynne Publication_Date: Unknown Title: GAP: Feeding and seasonality of gray whales in Ugak Bay; Kodiak Island Alaska Geospatial_Data_Presentation_Form: table (non-digital) Abstract: In this project, we propose to assess the seasonal importance of the Ugak Bay region to gray whales by documenting a) their monthly presence, distribution and relative abundance and b) the timing, duration, and intensity of their feeding activity. Seasonal abundance, distribution, and feeding We conducted systematic monthly surveys along transects traversing waters between Cape Chiniak and Dangerous Cape and approximately 10nm offshore. Surveys were scheduled monthly; the exact timing was dictated by weather and sighting conditions (minimal conditions of 1500 ceiling and Beaufort 4). A team of 2-3 observers flew the survey in a Cessna 206 on floats at an altitude of 1000ft and speed of 100kn. They marked the GPS location and estimated group size of whales spotted from transects in order to estimate relative abundance and density of gray whales in the area. The plane broke from effort and circled groups to ascribe an activity code to the whales based on evidence of plumes/fecal trails and other behaviors. Identity and diet Vessel-based surveys were conducted in July 2008 and June 2010 to approach,

2 identify, and collect samples from individual gray whales in Ugak Bay. Individuals were photographed to establish their identity and document visual evidence of body condition. Whenever encountered, we sampled the mud plumes and fecal clouds associated with feeding whales to determine what the whales are feeding on. We collectedsamples by towing or dipping a small-mesh plankton net through the plumes. Visible prey items and remains will be preserved in 10% seawater buffered formalin for subsequent identification. Prey availability We identified prey available to gray whales in Ugak Bay in 2008 through a combination of fixed-random sampling and focal sampling in areas where whales are feeding. We propose to revisit six random sites that were sampled in 2002 twice during the 7 day survey. At these sampling sites, one series of samples was collected on an ebbing tide and the other on a flooding tide. For each series, a 0.1-m2 van Veen grab weighing 88.7 kg (including a 32-kg lead weight) was used to collect benthic/epibenthic invertebrates and a CTD was cast to record temperature and salinity profiles. Purpose: The Gulf Apex Predator-prey program (GAP) was initiated in1999 by University of Alaska Fairbanks faculty in Kodiak to address trophic-level questions of immediate biological and economic concern in the western Gulf of Alaska. The program s goal is to document trophic relationships between Steller sea lions, their prey, competitors, and predators in the Kodiak region. Fundamental to the GAP program is the integration of distinct but related hypothesis-driven research projects. Although focused on sea lion concerns, GAP s interrelated studies also broadly assess the degree of dietary overlap among Kodiak s sympatric apex predators while exploring processes that drive populations of their prey within a dynamic marine environment. These studies overlap spatially and temporally, allowing synchronous collection of predator and prey data and synoptic assessment of their seasonal interactions. The Gulf Apex Predator-prey program is planned as a multiyear sampling effort that will allow monitoring inter-annual variability against which effects of human intervention may be compared. GAP investigators strive to facilitate synergistic linkage to related studies and efficiently broaden research beyond the scope of individual projects and have already fostered collaboration with fisheries and marine mammal researchers within the National Marine Fisheries Service (NMFS) Alaska Fisheries Science Center and Alaska Department of Fish and Game (ADFG). Supplemental_Information: [Provide additional information not covered elsewhere and/or important information such as related studies, data set limitations, and notifications] Time_Period_of_Content: Time_Period_Information: Range_of_Dates/Times: Beginning_Date: Ending_Date: 2011 Currentness_Reference: ground condition

3 Status: Progress: Planned Maintenance_and_Update_Frequency: Continually Spatial_Domain: Description_of_Geographic_Extent: Vessel surveys took place at the mouth of Ugak Bay on the east side of Kodiak Island. The geographic range of aerial surveys was variable depending on survey goal, but generally focused on the north half of the Kodiak archipelago. Bounding_Coordinates: Keywords: Theme: Theme: Place: Taxonomy: Keywords/Taxon: West_Bounding_Coordinate: East_Bounding_Coordinate: North_Bounding_Coordinate: South_Bounding_Coordinate: Theme_Keyword_Thesaurus: biota Theme_Keyword: marine mammals Theme_Keyword: gray whales Theme_Keyword: cumaceans Theme_Keyword_Thesaurus: einvornment Theme_Keyword: photo-identification Theme_Keyword: aerial surveys Theme_Keyword: vessel surverys Theme_Keyword: vanveen grab Place_Keyword_Thesaurus: None Place_Keyword: Gulf of Alaska Place_Keyword: Ugak Bay Place_Keyword: Kodiak Island Place_Keyword: Alaska Taxonomic_Keyword_Thesaurus: None Taxonomic_Keywords: single species Taxonomic_Keywords: animals Taxonomic_Keywords: invertebrates

4 Taxonomic_Keywords: mammals Taxon_Rank_Name: Kingdom Taxon_Rank_Value: Animalia Taxon_Rank_Name: Phylum Taxon_Rank_Value: Chordata Taxon_Rank_Name: Class Taxon_Rank_Value: Mammalia Taxon_Rank_Name: Order Taxon_Rank_Value: Cetacean Taxon_Rank_Name: Family Taxon_Rank_Value: Eschrichtidae Taxon_Rank_Name: Genus Taxon_Rank_Value: Eschrichtius Taxon_Rank_Name: Species Taxon_Rank_Value: robustus Applicable_Common_Name: Gray whale Taxon_Rank_Name: Suborder Taxon_Rank_Value: Mysticeti Access_Constraints: No restriction for accessing this dataset Use_Constraints: Must cite originator if used in publications, reports, presentations, etc. Point_of_Contact: Contact_Information: Contact_Person_Primary: Contact_Person: Bree Witteveen Contact_Organization: University of Alaska Fairbanks Contact_Address: Address_Type: mailing and physical Address: 118 Trident Way

5 City: Kodiak State_or_Province: Alaska Postal_Code: Contact_Voice_Telephone: Required element. Contact_Electronic_Mail_Address: Data_Set_Credit: Financial support was provided by the NOAA/NMFS Grant NA08NMF awarded to the University of Alaska's Gulf Apex Predator Project (GAP) Back to Top Data_Quality_Information: Logical_Consistency_Report: Sightings were plotted in GIS to determine the accuracy of their locations. Positions that were determined to be inaccurate were evaluated and corrected. Completeness_Report: There are some aerial sightings with either no time or not latitude and longitude. This is due to a failure of the GPS device to record this data. Lineage: Process_Step: Back to Top Process_Description: Process_Date: Unknown Entity_and_Attribute_Information: Detailed_Description: Entity_Type: Entity_Type_Label: Grays_Ugak.xls Entity_Type_Definition: Excel workbook containing four worksheets. Worksheet "Sightings_Aerial" Contains date, time, and position of aerial gray whale sightings Worksheet "Sightings_Vessel" Contains date, time, and position of vessel gray whale sightings Worksheet "Mud_Grabs" Contains position, tide phase, and composition of bottom samples Worksheet "Plume_Grabs" Contains position and compsotion of sampled mud plumes Entity_Type_Definition_Source:

6 Attribute_Label: Date Date as M/DD/YYYY Attribute_Label: Time Time of day Attribute_Label: Latitude Latitudinal position in decimal degrees Attribute_Label: Longitude Longitudinal position in decimal degrees Attribute_Label: Number Number of animals in a sighting group Attribute_Label: Feeding_Plumes Presence or absense of feeding plume in an aerial sighting Attribute_Label: Tide

7 Phase of tide (incoming or outgoing) during mud grabs Attribute_Label: Polychaetes Count of polychaete invertebrates in bottom or plume sample Attribute_Label: Amphipods Count of amphiod invertebrates in bottom or plume sample Attribute_Label: Razor Clams Count of razor clams in bottom or plume sample Attribute_Label: Other inverts Count of other invertebrates in bottom or plume sample Attribute_Label: Bottom type Type of bottom Attribute_Label: Sighting_Number Number of gray whale sighting plume is associated with

8 Attribute_Label: Sample ID Unique identifier of plume sample Attribute_Label: Type Type of plume collected, either fecal or mouth plume Attribute_Label: Nematodes Count of nematode invertebrates in bottom or plume sample Attribute_Label: Hydromedusa Count of hydromedusa in bottom or plume sample Attribute_Label: Larval Fish Count of larval fish in bottom or plume sample Detailed_Description: Entity_Type: Entity_Type_Label: CTD hex files Entity_Type_Definition: 13 hex files from CTD casts named as YYYYMMDD_###.hex Entity_Type_Definition_Source: Detailed_Description: Entity_Type:

9 Entity_Type_Label: CTD cap files Entity_Type_Definition: 3 CTD cap files as YYYYMMDD_###.cap Entity_Type_Definition_Source: Overview_Description: Back to Top Entity_and_Attribute_Overview: This data set contains sightings of gray whales collected during aerial surveys beginning in 1993 through present, as well as sightings during vessels surveys conducted in 2008 and Entity_and_Attribute_Detail_Citation: Distribution_Information: Distributor: Contact_Information: Contact_Person_Primary: Contact_Person: Bree Witteveen Contact_Organization: University of Alaska Fairbanks Contact_Address: Address_Type: mailing and physical Address: 118 Trident Way City: Kodiak State_or_Province: Alaska Postal_Code: Country: USA Contact_Voice_Telephone: Contact_Facsimile_Telephone: Contact_Electronic_Mail_Address: bree.witteveen@alaska.edu Distribution_Liability: Consult contact source for distribution liability Back to Top Metadata_Reference_Information: Metadata_Date: Metadata_Contact: Contact_Information:

10 Contact_Person_Primary: Contact_Person: Bree Witteveen Contact_Organization: University of Alaska Fairbanks Contact_Address: Address_Type: mailing and physical Address: 118 Trident Way City: Kodiak State_or_Province: Alaska Postal_Code: Country: USA Contact_Voice_Telephone: Contact_Facsimile_Telephone: Contact_Electronic_Mail_Address: Metadata_Standard_Name: FGDC Biological Data Profile of the Content Standard for Digital Geospatial Metadata Metadata_Standard_Version: FGDC-STD Metadata_Access_Constraints: None Metadata_Use_Constraints: None Metadata_Security_Information: Back to Top Metadata_Security_Classification_System: None Metadata_Security_Classification: Unclassified Metadata_Security_Handling_Description: None