At-sea seabird observations and effort during the TEMPO voyage of the RV Investigator (Jan-Mar 2021)

Brief description

This metadata record describes at-sea seabird observation dataset collected during the 2021 TEMPO (Trends in Euphausiids off Mawson, Predators, and Oceanography) voyage onboard the RV Investigator (see Kelly et al. 2021 for more details on the voyage). The primary goal of TEMPO was to collect data to estimate krill biomass with a view to update the precautionary catch limit for krill in CCAMLR’s Division 58.4.2-East. The aim of the survey was also to improve our understanding on the connectivity of the krill population, and overlap between krill and predators. The TEMPO voyage ran from February to March 2021. The survey consisted of six major acoustic line-transects to estimate krill biomass and to observe swarm behaviour across ecological and density gradients within the survey area south of 62°S between 55° and 80° E, and a single fine-scale krill box acoustic survey off the Mawson coast. Comprehensive oceanographic (CTDs, XBTs, Argo floats) and biological (plankton) sampling were also conducted to understand the habitat environment of krill and its predators. Predator observation was undertaken throughout the voyage to improve our understanding on the connectivity of the krill population, and overlap of distribution between krill and predators. The information gathered contributes to the design of tractable and sustainable long-term monitoring plan and to evaluate spatial management of the krill fishery.

Two seabird observers undertook observations from: 1) an enclosed observation deck above the bridge of the RV Investigator (approx. eye height of 24.3m); 2) on the observation deck 05 with the cetacean observers (approx. eye height of 18.4m); 3) and astern on the same level as the observation deck. Observing was undertaken during daylight hours, and during fair-excellent sighting conditions. Formal observing for seabirds was suspended when the vessel stopped/slowed for other sampling operations. During searching effort, one seabird observer scanned for seabirds and the other logged observations (via radio) in the enclosed observation above the bridge. Seabird searching effort was undertaken with naked-eye and with 10 x 42 binoculars (Swarovski NL Pure). Observers searched in a 300 m quadrat on one side of the vessel (specific side could change, as was best for observing conditions). A number of different seabird observation processes were trialled during the TEMPO voyage, including continuous observations and a snapshot approach with distance sampling (which aims to minimise bias introduced by flying seabirds), and observations astern to try to account for ‘followers’, and incidental sightings outside of these. (See Gierdrum et al. 2012 for more details on the observation processes.) It is hoped these trials will help guide development in the near future of methods for at-sea surveys for seabirds in East Antarctica.

Seabird observers achieved sighting effort along 3853 km of trackline, over 126 hrs, both within the TEMPO survey area, and along the transit home.



References
Gjerdrum, C., D.A. Fifield, and S.I. Wilhelm. 2012. Eastern Canada Seabirds at Sea (ECSAS) standardized protocol for pelagic seabird surveys from moving and stationary platforms. Canadian Wildlife Service Technical Report Series No. 515. Atlantic Region. vi + 37 pp.
Kelly, N., Bestley, S., Burns, A., Clarke, L., Collins, K., Cox, M., Hamer, D., King, R., Kitchener, J., Macaulay, G., Maschette, D., Melvin, J., Miller, B., Smith, A., Suter, L., Westwood, K., Wotherspoon, S. and Kawaguchi, S. (2021). An overview of the ecosystem survey to quantify krill abundance for krill monitoring and management in Eastern Sector of CCAMLR Division 58.4.2: Trends in Euphausiids off Mawson, Predators, and Oceanography “TEMPO”, Working Group on Ecosystem Monitoring and Management, CCAMLR, WG-EMM-2021/07, 26pp.


TEMPO seabird observation data README

Below are basic descriptors of the columns that appear in the various tables describing effort (continous, snapshot, incidental and stern), seabird sightings and weather obs from the TEMPO voyage.
Name of the csv files for each table are given in the quotation marks below.

Nat Kelly 22 December 2023
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"TEMPO_seabird_Effort.csv"
UID: effort row ID, as appears in original database
DateTime: date-time sighting entry is started, in UTC.
UTC: date-time effort entry closed, in UTC
PCLocalTime:
EffortStatus: whether on or off effort; see Topic 'EffortStatus' in Lookup Table.
Snapshotfreq: Duration of snapshop observation process in minutes.
Side: Port or Starboard
Observer01: Primary observer
DataLogger: person logging data
Notes:
Platform: position of primary observer on RV Investigator; see Topic 'Platform' in Lookup Table
OffEffReason: Reason observer(s) going off effort; see Topic 'EventCode' in Lookup Table.


"TEMPO_seabird_environment.csv"
UID: weather/enviro data entry ID, as appears in original database
Time: date-time weather entry is started, in UTC.
UTC: date-time weather entry closed, in UTC
PCLocalTime:
Sightability: overall sightability score, see Topic 'Sightability' on the Lookup table
SeaState: Beafort sea state, see Topic 'Sea state' on the Lookup table
Swell: swell, see Topic 'Swell' on the Lookup table
Weather: weather code, see Topic 'Weather' on the Lookup table
CloudCover: cloud cover, in oktas
Visibility: visibility distance code, see Topic 'Visibility' on the Lookup table
Intensity: Glare intensity, see Topic 'glare' on the Lookup table
Glare_start: which angle does the glare start, relative to ship's heading
Glare_stop: which angle does the glare stop, relative to ship's heading
Ice: ice concentration code, see Topic 'Ice' on the Lookup table
IceType: ice type, see Topic 'IceType' on the Lookup table
Notes: any observation notes
Longitude:
Latitude:


"TEMPO_seabird_Continuous.csv"
UID: continuous sighting data entry ID, as appears in original database
Time: date-time continuous sighting entry is started, in UTC.
UTC: date-time continuous sighting entry closed, in UTC
PCLocalTime:
ContSigntNo: unique continuous sighting number
ContSpec01: species code; see Topic 'SightingsSpecies...' in Lookup table
Count01: number of animals in the group sighted
Distance01: perpendicular distance to the sighting from the trackline, see Topic 'Distance' on the Lookup table
PhotoTaken: Was a photo taken?
Notes:


"TEMPO_seabird_Incidental.csv"
UID: incidental sighting data entry ID, as appears in original database
Time: date-time incidental sighting entry is started, in UTC.
UTC: date-time incidental sighting entry closed, in UTC
PCLocalTime:
IncidNo: unique incidental sighting number
IncidSpec01: species code; see Topic 'SightingsSpecies...' in Lookup table
Count01: number of animals in the group sighted
...(includes several columns to account for multiple sightings/groups at the same time)
PhotoTaken: Was a photo taken?
Notes:


"TEMPO_seabird_Snapshot.csv"
UID: snapshot sighting data entry ID, as appears in original database
Time: date-time snapshot sighting entry is started, in UTC.
UTC: date-time snapshot sighting entry closed, in UTC
PCLocalTime:
SnapshotNo: unique snapshot sighting number
SnapshotSpec01: species code; see Topic 'SnapshotSpecies' in Lookup table. Please note, "SnapshotSpec01" did not record properly and shouldn't be used in subsequent analyses
Count01: number of animals in the group sighted
Distance01: perpendicular distance to the sighting from the trackline, see Topic 'Distance' on the Lookup table
...(includes several columns to account for multiple sightings/groups at the same time)
PhotoTaken: Was a photo taken?
Notes:

"TEMPO_seabird_Stern.csv"
UID: stern sighting data entry ID, as appears in original database
Time: date-time stern sighting entry is started, in UTC.
UTC: date-time stern sighting entry closed, in UTC
PCLocalTime:
SternNo: unique stern sighting number
SternSpec01: species code; see Topic 'SnapshotSpecies' in Lookup table. Please note, "SnapshotSpec01" did not record properly and shouldn't be used in subsequent analyses
Count01: number of animals in the group sighted
...(includes several columns to account for multiple sightings/groups at the same time)
PhotoTaken: Was a photo taken?
Notes:


"TEMPO_seabird_gps.csv"
NOTE: gps data in this csv was only consistently recorded when observers were on effort. For the full gps data for the entire voyage, see the MNF/RV Investigator data portals.

Lineage

Progress Code: completed