Aquatic Environment and Biodiversity Annual Review 2012

AEBAR 2012: Marine Biodiversity
Specific Objective 2: To continue the analysis of opportunistic seabird and marine mammal
distribution observations from this and previous BioRoss voyages and published records, and in
relation to environmental variables. (Draft report completed.)
The distributions of the seabird and marine mammal taxa reported from two RV Tangaroa voyages
(TAN200602 and TAN200802) have been mapped. These represent the count data of seabirds
recorded during the 2006 Ross Sea voyage and the locations of images of seabird taxa (recorded
opportunistically) from the 2008 IPY-CAML voyage and records from observers from the
toothfish fishery. The distributions include the presence data of taxa over waters south of about 60°
S to the Ross Sea. Additional work to explain the distribution of the most common seabirds in
relation to environmental variables has been proposed but has not yet started.
Specific Objective 3: To identify and determine near-surface spatial distribution, diversity and
abundance of phytoplankton, and zooplankton, based on Continuous Plankton Recorder samples
collected during transit to and from the Ross Sea.
The Continuous Plankton Recorder (CPR) was deployed during the IPY voyage, both during the
transit to and from Wellington, and within the Ross Sea itself. CPR silks collected during transit
were preserved in formalin and sent to Australian Antarctic Division where they were analyzed for
zooplankton species composition and abundance. CPR silks collected within the Ross Sea were
preserved in ethanol for the analysis of epipelagic meroplankon. In addition to the zooplankton,
sampling, water samples were collected for phytoplankton analysis using the underway water
sampling system from a depth of 7 m, corresponding to the approximate depth of CPR sampling.
In addition to the work described above, ICOMM (International census of marine microbes)
samples collected during the IPY-CAML survey (10 m depth x 4 stations) have been analysed by
collaborators in the USA (Ghiglione et al. 2012).
Specific Objective 4: To analyse underway and station data collected on salinity, temperature and
chlorophyll a data, spot optical measurements with the SeaWiFS Profiling Multichannel
Radiometer (SPMR), surface samples for chlorophyll a, nutrients and particle analysis as well as
underway nutrient observations to allow ground-truthing of data collection from satellites and
identify water masses (e.g. surface seawater temperature, and chlorophyll concentration).
This objective addressed background physical and surface biological conditions at the time of the
IPY-CAML survey. The objective was split into two parts 1. characterisation of the biological
environment and bio-optical regime using continuous underway sampling, and 2. identification of
thermohaline fronts using discrete and underway sampling of temperature, salinity and nutrient
profiles. The combined dataset was used to validate satellite data of temperature and surface
chlorophyll distributions, providing a synoptic overview of physical and biological conditions
during the survey.
Specific Objective 5: To identify and determine the spatial distribution, abundance (biomass),
diversity, and size structure of epipelagic, mesopelagic (and possibly bathypelagic) species using
acoustics data, target strength estimation techniques and net sampling.
This objective addressed samples collected using the mesopelagic trawl and acoustic data collected
from midwater marks using the ship’s echosounders. Results were presented at five conferences:
1) CAML-IPY Symposium in Genoa, Italy, May 2009; 2) CCAMLR SG-ASAM meeting in
Genoa, Italy, May 2009; 3) Antarctic New Zealand conference in Auckland, July 2009; New
Zealand Marine Sciences’ Society conference in Stewart Island, July 2011; and International Polar
Year Symposium, Montreal, Canada, April 2012. Results were also presented to the Ross Sea
Bioregionalisation workshop in Wellington in June 2009 (see below) and were incorporated in the
bioregionalisation reports prepared for CCAMLR (SC-CAMLR-XXIV-BG-25) and the Antarctic
Treaty Consultative Meeting (ATCM). Reports include those by Koubbi et al. (2011), O’Driscoll
(2009), O’Driscoll et al. (2009, 2011), Pinkerton et al. (in press), and Hanchet et al. (in press).
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