CCAMLR

We outline progress on current work aimed to improve estimates of flying seabird abundance, and ultimately krill consumption, from land-based breeding bird counts of five species (Antarctic petrel, Cape petrel, southern fulmar, snow petrel and Wilson’s storm petrel) in Divisions 58.4.1 and 58.4.2. We compiled information on the historical search effort in potential seabird breeding habitat in these Divisions and conclude that only 2-3% of potential flying seabird breeding habitat has been searched for breeding populations. We conclude that a compilation of historical population counts where searches have been made substantially under-estimates the true breeding populations across all habitat, and alternate approaches are required to realistically estimate seabird abundance, and from that consumption. This conclusion is supported by preliminary results from a broad-scale sample survey of snow petrels. This work is an important contribution to estimating krill consumption by predators in Divisions 58.4.1 and 58.4.2 as part of a risk assessment for these Divisions. It complements similar work on other predator groups in the region including pack-ice seals and Adelie penguins and will contribute to estimating total krill consumption by these predator groups.

We provide a brief update on the progress of our CEMP Special Fund project ‘Developing an image processing software tool for analysis of camera network monitoring data’. The project was initiated with support from the CEMP Fund in 2015/16. A software programmer has been engaged and is currently working within the Australian Antarctic Division’s Data Centre to refine the software and develop post-processing code according to specifications developed in consultation with the CCAMLR camera user community. We expect to complete a package of software and post-processing code by early 2018.

The distribution and abundance of krill aggregation inhabiting the Subarea 48.1, which includes the Elephant Island peripheries and the west and south of the South Shetland Island, were estimated using an acoustics survey. Acoustic data were collected with 38 and 120 kHz from April 13 to 24 in 2016 and 38 and 200 kHz from March 6 to 14 in 2017. Krill were collected by the commercial middle trawl fishing vessel. The data were processed and analyzed following CCAMLR standard protocols using swarm integration (SHAPES module within that software for swarm identification) based on data from a transect-based survey. The weighted krill density and biomass were estimated to be 0.20 g/m² and 18 thousand tons (CV=33.8%) applying S_v difference 3.96-5.91 dB and 0.92 g/m² and 83 thousand tonnes (CV=31.4%) applying S_v difference -3.0-13.8 dB in 2017, respectively. Krill density and biomass were significantly higher in 2016 than those in 2017.

This paper aims to bring to light specific issues which precluded support by Norway of the Weddell Sea MPA proposal tabled to CCAMLR in 2016 by the delegation of the European Union and its Member States. We present results from Marxan and other analyses conducted for the purpose of evaluating aspects of the Weddell Sea MPA planning process which were integral to the development of the proposal, focusing on the suitability of the Marxan analysis to inform MPA border delineation and the potential impact to fisheries. We pose questions and make recommendations regarding the technical and procedural decisions made during the Weddell Sea MPA planning process, and discuss these concerns in the context of the transparency of the process, the consistency with other CCAMLR MPA planning processes, and Norway’s commitment to ensuring that any area-based management it supports is founded on a consistent and rigorous scientific basis.   

Breeding birds can increase their foraging efforts to feed chicks after hatching. We investigated how chinstrap penguins (Pygoscelis antarctica) differ foraging diving behaviors with breeding stages. During incubation and chick-rearing period, from December 2015 to January 2016 on King George Island, Antarctica, diving characteristics of breeding chinstrap penguin parents were recorded by deploying GPS and Time-Depth Recorder (TDR). Our results showed that chinstrap penguins have wider-range diving areas and longer foraging trips during incubation period while they dive in on-shore areas for a short trip hours during chick-rearing period. In addition, chinstrap penguins exhibited deeper dive depths during chick-rearing than during incubation. Our results suggest that chinstrap parents change their foraging area and dive depth between incubation and chick-rearing, possibly due to the increased need of chick-feeding and the temporal changes in prey availability between the two reproduction stages.

To develop a long-term ecological research program at a breeding site of Adélie penguins, located in the Northern Victoria Land Coast, the Korea Polar Research Institute (KOPRI) carried out a preliminary survey on the population size and foraging trips of penguins at Cape Hallett. All sub-colonies were mapped using a portable DGPS and the data were complemented by comparing them with aerial images using an unmanned aerial vehicle (UAV). The Cape Hallett colony was composed of approximately 700 sub-colonies occupied by 53,450 pairs of Adélie penguins in 2016. The foraging area of the Adélie penguins (Pygoscelis adelie) determined from our loggers was 218.8 ± 366.8 km² (mean ± SD).

We provide a brief update on the progress of our project “Tracking the overwinter habitat use of krill-dependent predators from Subarea 48.1”. The project was initiated with support from the CEMP Special Fund in 2015/16. With the assistance of the Secretariat, we purchased 150 ARGOS-based satellite transmitters and successfully deployed 130 instruments during the 2016/17 breeding season at sites including King George Island, Livingston Island, Cierva Cove, and Galindez Island. Twenty tags intended for juvenile Adélie penguins were not deployed due to logistical limitations (10 tags) and failed delivery (10 tags).  Data collection continues for one juvenile penguin and 50 adult penguins as of 13 June 2017. In total, we collected usable data from 118 deployments. Data indicate high utilization of coastal zones among gentoo penguins, while chinstrap penguins and Adélie juveniles exhibited larger-scale movements into pelagic areas that span from the Ross Sea to the South Sandwich Islands.