Arrow squid, Nototodarus gouldi, are managed as a single population in Australia; however, it is ... more Arrow squid, Nototodarus gouldi, are managed as a single population in Australia; however, it is unknown whether N. gouldi caught in Victoria and the Great Australian Bight are from separate stocks. This study examines whether N. gouldi caught in these two spatially separated locations of southern Australia are different stocks. Fourier shape analysis of statoliths was used to determine whether discrete phenotypic stocks exist; whereas statolith element concentrations were used to determine where individuals from both locations are likely to have hatched. Comparing statolith shape from squid collected in Victoria to squid collected in the Great Australian Bight suggested significant phenotypic heterogeneity in stocks; whereas statolith elemental composition analysis suggests that N. gouldi caught at either location hatched throughout their distribution. Although N. gouldi caught in the Great Australia Bight and Victoria appeared to be separate stocks, squid from both regions are imp...
... Stephanie Barrett and Graeme Dunstan of CSIRO provided helpful criticisms of the manuscript. ... more ... Stephanie Barrett and Graeme Dunstan of CSIRO provided helpful criticisms of the manuscript. REFERENCES 1. Cheshire, AC and Hallam, ND (1988) Mar. Ecol. ... 10. Nichols, PD, Skerratt, JH, Davidson, A., Burton, H. and McMeekin, TA (1991) Phytochemistry 30, 3209. 11. ...
... We observed deleterious interactive effects of warming and acidification on S.neu-mayeri, and... more ... We observed deleterious interactive effects of warming and acidification on S.neu-mayeri, and it is clear that more comparative ... and logistical support including Rob King, Steve Whiteside, John van den Hoff, Andrew Bryant, Clive Strauss, Charmaine Alford, Kathryn Brown, Lara ...
The gametes of marine invertebrates are being spawned into an ocean that is simultaneously warmin... more The gametes of marine invertebrates are being spawned into an ocean that is simultaneously warming and decreasing in pH. Predicting the potential for interactive effects of these stressors on fertilization is difficult, especially for stenothermal polar invertebrates adapted to fertilization in cold, viscous water and, when decreased sperm availability may be an additional stressor. The impact of increased temperature (2-4 °C above ambient) and decreased pH (0.2-0.4 pH units below ambient) on fertilization in the Antarctic echinoid Sterechinus neumayeri across a range of sperm concentrations was investigated in cross-factorial experiments in context with near future ocean change projections. The high temperature treatment (+4 °C) was also used to assess thermal tolerance. Gametes from multiple males and females in replicate experiments were used to reflect the multiple spawner scenario in nature. For fertilization at low sperm density we tested three hypotheses, 1) increased temperature enhances fertilization success, 2) low pH reduces fertilization and, 3) due to the cold stenothermal physiology of S. neumayeri, temperature would be the more significant stressor. Temperature and sperm levels had a significant effect on fertilization, but decreased pH did not affect fertilization. Warming enhanced fertilization at the lowest sperm concentration tested likely through stimulation of sperm motility and reduced water viscosity. Our results indicate that fertilization in S. neumayeri, even at low sperm levels potentially found in nature, is resilient to near-future ocean warming and acidification.
... The study of yolk lipid reserves and their dynamics has proven useful in exploring aspects of... more ... The study of yolk lipid reserves and their dynamics has proven useful in exploring aspects of maternal provi-sioning during embryonic development in a number of marine teleost (Wiegand 1996), cephalopods (Clarke et al. 1994) and invertebrates (Morais et al. 2002). ...
Freshly caught male and female Euphausia superba from the same swarm exhibited different rates of... more Freshly caught male and female Euphausia superba from the same swarm exhibited different rates of mortality subsequent to capture. Mortality was significantly higher for reproductive males (100%, n= 68) than for females (3%, n= 186) within the first 3 d of ...
Nyctiphanes australis contained, on a dry weight basis, an average of 52% crude protein and 5.0 t... more Nyctiphanes australis contained, on a dry weight basis, an average of 52% crude protein and 5.0 to 9.5% lipid. The fatty acid profile of N. australis was markedly unsaturated, with a mean total ?3 fatty acid content of 48.6±2.4% of total fatty acids. N. australis contained high levels of the essential long-chain polyunsaturated fatty acids eicosapentaenoic (EPA, 20:5?3) and docosahexaencic
Arrow squid, Nototodarus gouldi, are managed as a single population in Australia; however, it is ... more Arrow squid, Nototodarus gouldi, are managed as a single population in Australia; however, it is unknown whether N. gouldi caught in Victoria and the Great Australian Bight are from separate stocks. This study examines whether N. gouldi caught in these two spatially separated locations of southern Australia are different stocks. Fourier shape analysis of statoliths was used to determine whether discrete phenotypic stocks exist; whereas statolith element concentrations were used to determine where individuals from both locations are likely to have hatched. Comparing statolith shape from squid collected in Victoria to squid collected in the Great Australian Bight suggested significant phenotypic heterogeneity in stocks; whereas statolith elemental composition analysis suggests that N. gouldi caught at either location hatched throughout their distribution. Although N. gouldi caught in the Great Australia Bight and Victoria appeared to be separate stocks, squid from both regions are imp...
... Stephanie Barrett and Graeme Dunstan of CSIRO provided helpful criticisms of the manuscript. ... more ... Stephanie Barrett and Graeme Dunstan of CSIRO provided helpful criticisms of the manuscript. REFERENCES 1. Cheshire, AC and Hallam, ND (1988) Mar. Ecol. ... 10. Nichols, PD, Skerratt, JH, Davidson, A., Burton, H. and McMeekin, TA (1991) Phytochemistry 30, 3209. 11. ...
... We observed deleterious interactive effects of warming and acidification on S.neu-mayeri, and... more ... We observed deleterious interactive effects of warming and acidification on S.neu-mayeri, and it is clear that more comparative ... and logistical support including Rob King, Steve Whiteside, John van den Hoff, Andrew Bryant, Clive Strauss, Charmaine Alford, Kathryn Brown, Lara ...
The gametes of marine invertebrates are being spawned into an ocean that is simultaneously warmin... more The gametes of marine invertebrates are being spawned into an ocean that is simultaneously warming and decreasing in pH. Predicting the potential for interactive effects of these stressors on fertilization is difficult, especially for stenothermal polar invertebrates adapted to fertilization in cold, viscous water and, when decreased sperm availability may be an additional stressor. The impact of increased temperature (2-4 °C above ambient) and decreased pH (0.2-0.4 pH units below ambient) on fertilization in the Antarctic echinoid Sterechinus neumayeri across a range of sperm concentrations was investigated in cross-factorial experiments in context with near future ocean change projections. The high temperature treatment (+4 °C) was also used to assess thermal tolerance. Gametes from multiple males and females in replicate experiments were used to reflect the multiple spawner scenario in nature. For fertilization at low sperm density we tested three hypotheses, 1) increased temperature enhances fertilization success, 2) low pH reduces fertilization and, 3) due to the cold stenothermal physiology of S. neumayeri, temperature would be the more significant stressor. Temperature and sperm levels had a significant effect on fertilization, but decreased pH did not affect fertilization. Warming enhanced fertilization at the lowest sperm concentration tested likely through stimulation of sperm motility and reduced water viscosity. Our results indicate that fertilization in S. neumayeri, even at low sperm levels potentially found in nature, is resilient to near-future ocean warming and acidification.
... The study of yolk lipid reserves and their dynamics has proven useful in exploring aspects of... more ... The study of yolk lipid reserves and their dynamics has proven useful in exploring aspects of maternal provi-sioning during embryonic development in a number of marine teleost (Wiegand 1996), cephalopods (Clarke et al. 1994) and invertebrates (Morais et al. 2002). ...
Freshly caught male and female Euphausia superba from the same swarm exhibited different rates of... more Freshly caught male and female Euphausia superba from the same swarm exhibited different rates of mortality subsequent to capture. Mortality was significantly higher for reproductive males (100%, n= 68) than for females (3%, n= 186) within the first 3 d of ...
Nyctiphanes australis contained, on a dry weight basis, an average of 52% crude protein and 5.0 t... more Nyctiphanes australis contained, on a dry weight basis, an average of 52% crude protein and 5.0 to 9.5% lipid. The fatty acid profile of N. australis was markedly unsaturated, with a mean total ?3 fatty acid content of 48.6±2.4% of total fatty acids. N. australis contained high levels of the essential long-chain polyunsaturated fatty acids eicosapentaenoic (EPA, 20:5?3) and docosahexaencic
Uploads