Evidence for a broad-scale decline in giant Australian cuttlefish (Sepia apama) abundance from non-targeted survey data

2015 ◽  
Vol 66 (8) ◽  
pp. 692 ◽  
Author(s):  
Thomas A. A. Prowse ◽  
Bronwyn M. Gillanders ◽  
Barry W. Brook ◽  
Anthony J. Fowler ◽  
Karina C. Hall ◽  
...  
Keyword(s):  
Marine Invertebrates ◽  
Species Abundance ◽  
South Australia ◽  
Bayesian Hierarchical ◽  
Aggregation Site ◽  
Breeding Grounds ◽  
Sepia Apama ◽  
Harvest Data ◽  
Trawl Surveys ◽  
Broad Scale

Little is known about the population trajectory and dynamics of many marine invertebrates because of a lack of robust observational data. The giant Australian cuttlefish (Sepia apama) is IUCN-listed as Near Threatened because the largest known breeding aggregation of this species in northern Spencer Gulf, South Australia, has declined markedly since the turn of the century. We used by-catch records from long-term trawl surveys to derive abundance data for S. apama and commercial cuttlefish harvest data as a measure of exploitation. Using Bayesian hierarchical models to account for zero-inflation and spatial dependence in these abundance counts, we demonstrated a high probability of broad-scale declines in the density of S. apama, particularly surrounding the primary aggregation site, which supports the recent closure of the entire S. apama fishery in northern Spencer Gulf. Historical harvest data were positively correlated with S. apama density estimated from the trawl surveys, suggesting that the commercial cuttlefish catch tracks the species abundance. Our results also indicated the possibility that the known S. apama breeding grounds might be supplemented by individuals that were spawned elsewhere in northern Spencer Gulf.

Talking camels: a consultation strategy for consent to conduct feral camel management on Aboriginal-owned land in Australia

2016 ◽  
Vol 38 (2) ◽  
pp. 125 ◽  
Author(s):  
Ben Kaethner ◽  
Peter See ◽  
Adam Pennington
Keyword(s):  
Informed Consent ◽  
South Australia ◽  
Landscape Scale ◽  
Northern Territory ◽  
Aboriginal Communities ◽  
Communication Techniques ◽  
Management Project ◽  
Landscape Types ◽  
Vast Area ◽  
Broad Scale

Thorough consultation and informed consent are required for any work on Aboriginal-owned land in Australia. Consultations for feral camel (Camelus dromedarius) management under the Australian Feral Camel Management Project across the Northern Territory, Western Australia and South Australia were conducted across a vast area, spanning a diversity of cultures and landscape types. Aboriginal organisations from these jurisdictions developed consultative processes that supported Aboriginal communities in making informed decisions on any removal of camels from their country. This article describes the communication techniques used to depict the feral camel issues and opportunities to Aboriginal communities at the local and landscape scale. The decisions that communities arrived at were varied, but consistently focussed on feral camel removal. Their decisions have led to broad-scale feral camel removal under the Australian Feral Camel Management Project, and beyond.

Combining management based indices with environmental parameters to explain regional variation in soil carbon under dryland cropping in South Australia

Soil Research ◽  
2013 ◽  
Vol 51 (8) ◽  
pp. 738 ◽  
Author(s):  
Lynne M. Macdonald ◽  
Tim Herrmann ◽  
Jeffrey A. Baldock
Keyword(s):  
Environmental Variables ◽  
Explanatory Power ◽  
Regional Scale ◽  
South Australia ◽  
Vapour Pressure Deficit ◽  
Environmental Parameters ◽  
Decomposition Processes ◽  
Historical Management ◽  
Broad Scale

Identifying drivers of variation in soil organic carbon (OC) at a regional scale is often hampered by a lack of historical management information. Focusing on red-brown-earth soils (Chromosol) under dryland agriculture in the Mid-North and Eyre Peninsula of South Australia, our aims were 2-fold: (i) to provide a baseline of soil OC stocks (0.3 m) and OC fractions (mid-infrared predictions of particulate, humus, and resistant OC in 0.1 m samples) in cropping and crop-pasture systems; and (ii) to evaluate whether the inclusion of management-based indices could assist in explaining regional-level variation in OC stocks and fractions. Soil OC stocks in both regions varied ~20 Mg ha–1, with higher OC stocks in the Mid-North (38 Mg ha–1) than the Eyre Peninsula (29.1 Mg ha–1). The humus OC fraction was the dominant fraction, while the particulate OC was the most variable. Environmental variables only partially explained soil OC variability, with vapour pressure deficit (VPD) offering the greatest potential and likely acting as an integrator of temperature and moisture on plant growth and decomposition processes. Differences between broad-scale cropping and crop–pasture systems were limited. In the Mid-North, variability in soil OC stocks and fractions was high, and could not be explained by environmental or management variables. Higher soil OC concentrations (0.1 m) in the Eyre Peninsula cropping than crop–pasture soils were largely accounted for in the particulate OC fraction and are therefore unlikely to represent a long-term stable OC pool. Use of the management data in index format added some explanatory power to the variability in OC stocks over the main environmental variables (VPD, slope) within the Eyre Peninsula cropping soils only. In the wider context, the management data were useful in interpreting differences between regional findings and highlighted difficulties in using uninformed, broad-scale management categories.

Using the giant Australian cuttlefish (Sepia apama) mass breeding aggregation to explore the life cycle of dicyemid parasites

2013 ◽  
Vol 58 (4) ◽  
Author(s):  
Sarah Catalano ◽  
Ian Whittington ◽  
Stephen Donnellan ◽  
Bronwyn Gillanders
Keyword(s):  
Life Cycle ◽  
South Australia ◽  
Life Cycle Stage ◽  
Maximum Amount ◽  
Energy Costs ◽  
Huge Number ◽  
Short Lifespan ◽  
Sepia Apama ◽  
Host Life ◽  
Seawater Samples

AbstractDicyemid mesozoan parasites, microscopic organisms found with high intensities in the renal appendages of benthic cephalopods, have a complex, partially unknown life cycle. It is uncertain at which host life cycle stage (i.e. eggs, juvenile, adult) new infection by the dispersive infusoriform embryo occurs. As adult cephalopods have a short lifespan and die shortly after reproducing only once, and juveniles are fast-moving, we hypothesize that the eggs are the life cycle stage where new infection occurs. Eggs are abundant and sessile, allowing a huge number of new individuals to be infected with low energy costs, and they also provide dicyemids with the maximum amount of time for survival compared with infection of juvenile and adult stages. In our study we collected giant Australian cuttlefish (Sepia apama) eggs at different stages of development and filtered seawater samples from the S. apama mass breeding aggregation area in South Australia, Australia, and tested these samples for the presence of dicyemid DNA. We did not recover dicyemid parasite cytochrome c oxidase subunit I (COI) nucleotide sequences from any of the samples, suggesting eggs are not the stage where new infection occurs. To resolve this unknown in the dicyemid life cycle, we believe experimental infection is needed.

scholarly journals Distribution and spatio-temporal biomass trends of red mullets across the Mediterranean

2020 ◽  
Vol 83 (S1) ◽  
pp. 43
Author(s):  
George Tserpes ◽  
Enric Massutí ◽  
Fabio Fiorentino ◽  
Maria Teresa Facchini ◽  
Claudio Viva ◽  
...  
Keyword(s):  
Cluster Analysis ◽  
Species Abundance ◽  
Dynamic Factor Analysis ◽  
Dynamic Factor ◽  
Combined Effects ◽  
Relative Importance ◽  
Mullus Surmuletus ◽  
The Mediterranean ◽  
Spatio Temporal ◽  
Trawl Surveys

The present work examines the spatio-temporal biomass trends of Mullus barbatus and Mullus surmuletus in the Mediterranean Sea through the analysis of a time series of data coming from the Mediterranean International Trawl Surveys (MEDITS), accomplished annually from 1994 to 2015. The biomass of both species showed clear declining trends below 150 to 200 m depth, which were steeper in the case of M. barbatus. Increases in temporal biomass trends were observed for M. barbatus from 2008 onward in most geographic sub-areas (GSAs), while stability was mostly observed for M. surmuletus. For both species, dynamic factor analysis revealed similarities among neighbouring GSAs and the subsequent cluster analysis identified two major GSA groups corresponding to the eastern and western basins of the Mediterranean. Overall, the results suggested that the combined effects of fishing and environmental conditions determine species abundance variations, but the relative importance of each component may vary among areas.

Dietary analysis of regurgitates and stomach samples from free-living Australian sea lions

2006 ◽  
Vol 33 (8) ◽  
pp. 661 ◽  
Author(s):  
Rebecca R. McIntosh ◽  
Brad Page ◽  
Simon D. Goldsworthy
Keyword(s):  
Prey Species ◽  
South Australia ◽  
Rock Lobster ◽  
Sea Lion ◽  
Free Living ◽  
Dietary Analysis ◽  
Sea Lions ◽  
Neophoca Cinerea ◽  
Australian Sea Lion ◽  
Sepia Apama

Dietary remains recovered from Australian sea lion (Neophoca cinerea) digestive tracts and regurgitate samples from Seal Bay (Kangaroo Island, South Australia) were used to identify prey species consumed. Four of eight digestive tracts collected (50%) contained prey items located only in the stomach. On the basis of biomass reconstruction of cephalopod prey remains, octopus contributed 40% of the biomass in the samples, giant cuttlefish (Sepia apama) contributed 30% and ommastrephid squids contributed 14% biomass. The remains of several fish species were found in the samples: leatherjacket (Monocanthidae), flathead (Platycephalus sp.), swallowtail (Centroberyx lineatus), common bullseye (Pempheris multiradiata), southern school whiting (Sillago flindersi) and yellowtail mackerel (Trachurus novaezelandiae). Southern rock lobster (Jasus edwardsii) and swimming crab (Ovalipes australiensis) carapace fragments, little penguin (Eudyptula minor) feathers and bones and shark egg cases (oviparous species and Scyliorhinidae sp.) were also identified.

First tests of hybrid acoustic/archival tags on squid and cuttlefish

2005 ◽  
Vol 56 (4) ◽  
pp. 425 ◽  
Author(s):  
George D. Jackson ◽  
Ron K. O'Dor ◽  
Yanko Andrade
Keyword(s):  
South Australia ◽  
Cost Effective ◽  
Reference Standard ◽  
Magnetic Island ◽  
Archival Tags ◽  
Near Shore ◽  
Sepia Apama ◽  
Cost Effective Alternative ◽  
Temperature Records ◽  
Temperature Depth

This study demonstrates the simultaneous use of acoustic and archival tags for obtaining data for near-shore species. Australian giant cuttlefish Sepia apama (off Whyalla, South Australia) and the tropical squid Sepioteuthis lessoniana (off Magnetic Island, Queensland, Australia) were tagged using a ‘hybrid’ tag consisting of a Vemco V8 acoustic tag potted with a Vemco minilog temperature–depth archival tag. Four of these animals were released and monitored inside radio-acoustic-positioning-telemetry (RAPT) buoy-system arrays that included bottom-mounted sensors that transmitted independent temperature records and a reference standard for sound conductivity and position. All were subsequently located out of RAPT range and two of the four archival tags were recovered. Tags were located using a boat-mounted hydrophone and VR60 receiver and recovery was aided by a diver operating a hand-held VUR96 receiver. This technology provides a cost-effective alternative to expensive satellite pop-up tags and is suitable for much smaller species that return to near-shore environments.

Predator swamping and supplementary feeding do not improve reintroduction success for a threatened Australian mammal, Bettongia lesueur

2016 ◽  
Vol 38 (2) ◽  
pp. 177 ◽  
Author(s):  
Hannah L. Bannister ◽  
Catherine E. Lynch ◽  
Katherine E. Moseby
Keyword(s):  
Site Fidelity ◽  
South Australia ◽  
Supplementary Feeding ◽  
Supplementary Food ◽  
European Settlement ◽  
Release Group ◽  
Population Establishment ◽  
Reintroduction Success ◽  
Broad Scale ◽  
Predator Swamping

Broad-scale Australian mammal declines following European settlement have resulted in many species becoming regionally or globally extinct. Attempts to reintroduce native mammals are often unsuccessful due to a suboptimal number of founders being used, high rates of predation and a lack of knowledge of the reintroduction biology for the species concerned. We trialled predator swamping and supplementary feeding in an attempt to offset predation and improve reintroduction success for the burrowing bettong (Bettongia lesueur) in arid South Australia. We compared population longevity of a large release group (1266 animals) with five releases of smaller groups (~50 animals at each). We compared release sites with (n = 5) and without (n = 1) supplementary food to determine whether site fidelity, body condition and reproduction were affected, and whether these traits aided population establishment. Predator swamping did not facilitate reintroduction success, with no bettongs detected more than 122 days after release. While supplementary food increased site fidelity and persistence at release sites, bettongs failed to establish successfully at any site. Neither predator swamping nor supplementary feeding enhanced reintroduction success at our sites but results suggested that supplementary feeding should be explored as an aid to reintroduction success for Australian mammals.

scholarly journals Status of southern right whales (Eubalaena australis) off Australia

2020 ◽  
pp. 103-110 ◽  
Author(s):  
John Bannister
Keyword(s):  
19Th Century ◽  
Western Australia ◽  
South Australia ◽  
Australian Population ◽  
Eubalaena Australis ◽  
Right Whales ◽  
Southern Right Whales ◽  
Breeding Grounds ◽  
History Of ◽  
The 19Th Century

The history of Australian right whaling is briefly reviewed. Most catching took place in the first half of the 19th century, with a peak inthe 1830s, involving bay whaling by locals and visiting whaleships in winter and whaling offshore in the summer. In the early 20th century,right whales were regarded as at least very rare, if not extinct. The first published scientific record for Australian waters in the 20th centurywas a sighting near Albany, Western Australia, in 1955. Increasing sightings close to the coast in winter and spring led to annual aerialsurveys off southern Western Australia from 1976. To allow for possible effects of coastwise movements, coverage was extended intoSouth Australian waters from 1993. Evidence from 19th century pelagic catch locations, recent sightings surveys, 1960s Soviet catch dataand photographically-identified individuals is beginning to confirm earlier views about likely seasonal movements to and from warm watercoastal breeding grounds and colder water feeding grounds. Increase rates of ca 7-13% have been observed since 1983. Some effects ofdifferent breeding female cohort strength are now beginning to appear. A minimum population size of ca 700 for the period 1995-97 issuggested for the bulk of the ‘Australian’ population, i.e. animals approaching the ca 2,000km of coast between Cape Leeuwin, WesternAustralia and Ceduna, South Australia.

scholarly journals Residency and Local Connectivity of White Sharks at Liguanea Island: A Second Aggregation Site in South Australia?

2015 ◽  
Vol 8 (1) ◽  
pp. 23-29 ◽  
Author(s):  
RL Robbins ◽  
M. Enarson ◽  
RW Bradford ◽  
WD Robbins ◽  
AG Fox
Keyword(s):  
Site Fidelity ◽  
South Australia ◽  
White Shark ◽  
The Other ◽  
Local Connectivity ◽  
Southern States ◽  
Aggregation Site ◽  
Close Proximity ◽  
Return Visits ◽  
High Degree

White sharks show a high degree of residency to specific aggregation sites, to which they return regularly over multiple years. Australian research has historically focused on single aggregation areas within each of the southern states where white sharks occur, but other key habitats likely exist and if so, will be important to identify to effectively monitor and protect threatened white shark populations. This study is the first to describe Liguanea Island as a second white shark aggregation site within South Australia, with residency periods and return visits recorded by multiple individuals. Eight sharks were detected at both Liguanea Island and the other known aggregation area in the state, the Neptune Islands, demonstrating movement between these locations. Sustained residency periods were recorded at both sites, although high periodic site fidelity was apparent with many individuals showing preference for the location at which they were tagged. Individual differences in site fidelity and residency patterns were found, although two sub-adult individuals were found to follow similar movement patterns. The implications of white shark movements, and the suggested identification of a second aggregation areas in close proximity are discussed.

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