Ionoluminescence (IL) combined with particle induced X-ray emission (PIXE) imaging has been employed to identify intrinsic growth bands in the spire region, and extrinsic bands at the growth edge of Australian Black-lip abalone shell (Haliotis rubra). Previous studies using optical flood cathodoluminescence, scanning electron microscope cathodoluminescence (SEM-CL) and Raman spectroscopy on samples from the same population suggest that the visible luminescence is due to Mn²⁺ activated calcium carbonate. In this study we confirm Mn²⁺ as the activator in both the spire and growth edge regions of the shell.

Boring predators and epibionts often damage the shells of molluscs. In abalone, spionid polychaete worms bore holes into the shell and live within the shell matrix (Shepherd and Huchette, 1997). Shepherd and Huchette (1997) found that these worms can infest entire populations, severely weakening the shells of some individuals which can lead to mortality. Given the potential consequences of boring attacks, do abalone show any response these attacks?

If abalone can be accurately aged, this would be a fundamental tool for more effective management of abalone fisheries.  Several authors have proposed ageing abalone by grinding or cutting abalone shells, and counting the shell layers deposited beneath the spire.  Other authors have cast doubt on this method.  What is uncertain is how reliable these age estimates are.  To construct useful models to assess and manage abalone stocks, it is important to know the accuracy of the data on which the model is based.  Furthermore, it is labour intensive to collect age data, and if these data are very inaccurate, then resources are wasted in collecting it.

This project aimed to find out how reliable and accurate the ageing method was, by investigating the timing and the periodicity of layer formation in abalone shells. It seemed possible that the ageing method might work reasonably in some areas, but not in others.  Thus we planned to repeat the work at many places in the hope that we could predict where ageing would be useful for managing the blacklip and greenlip abalone fisheries of Victoria, Tasmania, New South Wales and South Australia.

Ionoluminescence (IL) combined with particle induced X-ray emission (PIXE) imaging has been employed to identify intrinsic growth bands in the spire region, and extrinsic bands at the growth edge of Australian Black-lip abalone shell (Haliotis rubra). Previous studies using optical flood cathodoluminescence, scanning electron microscope cathodoluminescence (SEM-CL) and Raman spectroscopy on samples from the same population suggest that the visible luminescence is due to Mn²⁺ activated calcium carbonate. In this study we confirm Mn²⁺ as the activator in both the spire and growth edge regions of the shell.

Boring predators and epibionts often damage the shells of molluscs. In abalone, spionid polychaete worms bore holes into the shell and live within the shell matrix (Shepherd and Huchette, 1997). Shepherd and Huchette (1997) found that these worms can infest entire populations, severely weakening the shells of some individuals which can lead to mortality. Given the potential consequences of boring attacks, do abalone show any response these attacks?

If abalone can be accurately aged, this would be a fundamental tool for more effective management of abalone fisheries.  Several authors have proposed ageing abalone by grinding or cutting abalone shells, and counting the shell layers deposited beneath the spire.  Other authors have cast doubt on this method.  What is uncertain is how reliable these age estimates are.  To construct useful models to assess and manage abalone stocks, it is important to know the accuracy of the data on which the model is based.  Furthermore, it is labour intensive to collect age data, and if these data are very inaccurate, then resources are wasted in collecting it.

This project aimed to find out how reliable and accurate the ageing method was, by investigating the timing and the periodicity of layer formation in abalone shells. It seemed possible that the ageing method might work reasonably in some areas, but not in others.  Thus we planned to repeat the work at many places in the hope that we could predict where ageing would be useful for managing the blacklip and greenlip abalone fisheries of Victoria, Tasmania, New South Wales and South Australia.

Ionoluminescence (IL) combined with particle induced X-ray emission (PIXE) imaging has been employed to identify intrinsic growth bands in the spire region, and extrinsic bands at the growth edge of Australian Black-lip abalone shell (Haliotis rubra). Previous studies using optical flood cathodoluminescence, scanning electron microscope cathodoluminescence (SEM-CL) and Raman spectroscopy on samples from the same population suggest that the visible luminescence is due to Mn²⁺ activated calcium carbonate. In this study we confirm Mn²⁺ as the activator in both the spire and growth edge regions of the shell.

Boring predators and epibionts often damage the shells of molluscs. In abalone, spionid polychaete worms bore holes into the shell and live within the shell matrix (Shepherd and Huchette, 1997). Shepherd and Huchette (1997) found that these worms can infest entire populations, severely weakening the shells of some individuals which can lead to mortality. Given the potential consequences of boring attacks, do abalone show any response these attacks?

If abalone can be accurately aged, this would be a fundamental tool for more effective management of abalone fisheries.  Several authors have proposed ageing abalone by grinding or cutting abalone shells, and counting the shell layers deposited beneath the spire.  Other authors have cast doubt on this method.  What is uncertain is how reliable these age estimates are.  To construct useful models to assess and manage abalone stocks, it is important to know the accuracy of the data on which the model is based.  Furthermore, it is labour intensive to collect age data, and if these data are very inaccurate, then resources are wasted in collecting it.

This project aimed to find out how reliable and accurate the ageing method was, by investigating the timing and the periodicity of layer formation in abalone shells. It seemed possible that the ageing method might work reasonably in some areas, but not in others.  Thus we planned to repeat the work at many places in the hope that we could predict where ageing would be useful for managing the blacklip and greenlip abalone fisheries of Victoria, Tasmania, New South Wales and South Australia.

Ionoluminescence (IL) combined with particle induced X-ray emission (PIXE) imaging has been employed to identify intrinsic growth bands in the spire region, and extrinsic bands at the growth edge of Australian Black-lip abalone shell (Haliotis rubra). Previous studies using optical flood cathodoluminescence, scanning electron microscope cathodoluminescence (SEM-CL) and Raman spectroscopy on samples from the same population suggest that the visible luminescence is due to Mn²⁺ activated calcium carbonate. In this study we confirm Mn²⁺ as the activator in both the spire and growth edge regions of the shell.

Boring predators and epibionts often damage the shells of molluscs. In abalone, spionid polychaete worms bore holes into the shell and live within the shell matrix (Shepherd and Huchette, 1997). Shepherd and Huchette (1997) found that these worms can infest entire populations, severely weakening the shells of some individuals which can lead to mortality. Given the potential consequences of boring attacks, do abalone show any response these attacks?

If abalone can be accurately aged, this would be a fundamental tool for more effective management of abalone fisheries.  Several authors have proposed ageing abalone by grinding or cutting abalone shells, and counting the shell layers deposited beneath the spire.  Other authors have cast doubt on this method.  What is uncertain is how reliable these age estimates are.  To construct useful models to assess and manage abalone stocks, it is important to know the accuracy of the data on which the model is based.  Furthermore, it is labour intensive to collect age data, and if these data are very inaccurate, then resources are wasted in collecting it.

This project aimed to find out how reliable and accurate the ageing method was, by investigating the timing and the periodicity of layer formation in abalone shells. It seemed possible that the ageing method might work reasonably in some areas, but not in others.  Thus we planned to repeat the work at many places in the hope that we could predict where ageing would be useful for managing the blacklip and greenlip abalone fisheries of Victoria, Tasmania, New South Wales and South Australia.

Ionoluminescence (IL) combined with particle induced X-ray emission (PIXE) imaging has been employed to identify intrinsic growth bands in the spire region, and extrinsic bands at the growth edge of Australian Black-lip abalone shell (Haliotis rubra). Previous studies using optical flood cathodoluminescence, scanning electron microscope cathodoluminescence (SEM-CL) and Raman spectroscopy on samples from the same population suggest that the visible luminescence is due to Mn²⁺ activated calcium carbonate. In this study we confirm Mn²⁺ as the activator in both the spire and growth edge regions of the shell.

Boring predators and epibionts often damage the shells of molluscs. In abalone, spionid polychaete worms bore holes into the shell and live within the shell matrix (Shepherd and Huchette, 1997). Shepherd and Huchette (1997) found that these worms can infest entire populations, severely weakening the shells of some individuals which can lead to mortality. Given the potential consequences of boring attacks, do abalone show any response these attacks?

If abalone can be accurately aged, this would be a fundamental tool for more effective management of abalone fisheries.  Several authors have proposed ageing abalone by grinding or cutting abalone shells, and counting the shell layers deposited beneath the spire.  Other authors have cast doubt on this method.  What is uncertain is how reliable these age estimates are.  To construct useful models to assess and manage abalone stocks, it is important to know the accuracy of the data on which the model is based.  Furthermore, it is labour intensive to collect age data, and if these data are very inaccurate, then resources are wasted in collecting it.

This project aimed to find out how reliable and accurate the ageing method was, by investigating the timing and the periodicity of layer formation in abalone shells. It seemed possible that the ageing method might work reasonably in some areas, but not in others.  Thus we planned to repeat the work at many places in the hope that we could predict where ageing would be useful for managing the blacklip and greenlip abalone fisheries of Victoria, Tasmania, New South Wales and South Australia.

Ionoluminescence (IL) combined with particle induced X-ray emission (PIXE) imaging has been employed to identify intrinsic growth bands in the spire region, and extrinsic bands at the growth edge of Australian Black-lip abalone shell (Haliotis rubra). Previous studies using optical flood cathodoluminescence, scanning electron microscope cathodoluminescence (SEM-CL) and Raman spectroscopy on samples from the same population suggest that the visible luminescence is due to Mn²⁺ activated calcium carbonate. In this study we confirm Mn²⁺ as the activator in both the spire and growth edge regions of the shell.

Boring predators and epibionts often damage the shells of molluscs. In abalone, spionid polychaete worms bore holes into the shell and live within the shell matrix (Shepherd and Huchette, 1997). Shepherd and Huchette (1997) found that these worms can infest entire populations, severely weakening the shells of some individuals which can lead to mortality. Given the potential consequences of boring attacks, do abalone show any response these attacks?

If abalone can be accurately aged, this would be a fundamental tool for more effective management of abalone fisheries.  Several authors have proposed ageing abalone by grinding or cutting abalone shells, and counting the shell layers deposited beneath the spire.  Other authors have cast doubt on this method.  What is uncertain is how reliable these age estimates are.  To construct useful models to assess and manage abalone stocks, it is important to know the accuracy of the data on which the model is based.  Furthermore, it is labour intensive to collect age data, and if these data are very inaccurate, then resources are wasted in collecting it.

This project aimed to find out how reliable and accurate the ageing method was, by investigating the timing and the periodicity of layer formation in abalone shells. It seemed possible that the ageing method might work reasonably in some areas, but not in others.  Thus we planned to repeat the work at many places in the hope that we could predict where ageing would be useful for managing the blacklip and greenlip abalone fisheries of Victoria, Tasmania, New South Wales and South Australia.

Ionoluminescence (IL) combined with particle induced X-ray emission (PIXE) imaging has been employed to identify intrinsic growth bands in the spire region, and extrinsic bands at the growth edge of Australian Black-lip abalone shell (Haliotis rubra). Previous studies using optical flood cathodoluminescence, scanning electron microscope cathodoluminescence (SEM-CL) and Raman spectroscopy on samples from the same population suggest that the visible luminescence is due to Mn²⁺ activated calcium carbonate. In this study we confirm Mn²⁺ as the activator in both the spire and growth edge regions of the shell.

Boring predators and epibionts often damage the shells of molluscs. In abalone, spionid polychaete worms bore holes into the shell and live within the shell matrix (Shepherd and Huchette, 1997). Shepherd and Huchette (1997) found that these worms can infest entire populations, severely weakening the shells of some individuals which can lead to mortality. Given the potential consequences of boring attacks, do abalone show any response these attacks?

If abalone can be accurately aged, this would be a fundamental tool for more effective management of abalone fisheries.  Several authors have proposed ageing abalone by grinding or cutting abalone shells, and counting the shell layers deposited beneath the spire.  Other authors have cast doubt on this method.  What is uncertain is how reliable these age estimates are.  To construct useful models to assess and manage abalone stocks, it is important to know the accuracy of the data on which the model is based.  Furthermore, it is labour intensive to collect age data, and if these data are very inaccurate, then resources are wasted in collecting it.

This project aimed to find out how reliable and accurate the ageing method was, by investigating the timing and the periodicity of layer formation in abalone shells. It seemed possible that the ageing method might work reasonably in some areas, but not in others.  Thus we planned to repeat the work at many places in the hope that we could predict where ageing would be useful for managing the blacklip and greenlip abalone fisheries of Victoria, Tasmania, New South Wales and South Australia.

Ionoluminescence (IL) combined with particle induced X-ray emission (PIXE) imaging has been employed to identify intrinsic growth bands in the spire region, and extrinsic bands at the growth edge of Australian Black-lip abalone shell (Haliotis rubra). Previous studies using optical flood cathodoluminescence, scanning electron microscope cathodoluminescence (SEM-CL) and Raman spectroscopy on samples from the same population suggest that the visible luminescence is due to Mn²⁺ activated calcium carbonate. In this study we confirm Mn²⁺ as the activator in both the spire and growth edge regions of the shell.

Boring predators and epibionts often damage the shells of molluscs. In abalone, spionid polychaete worms bore holes into the shell and live within the shell matrix (Shepherd and Huchette, 1997). Shepherd and Huchette (1997) found that these worms can infest entire populations, severely weakening the shells of some individuals which can lead to mortality. Given the potential consequences of boring attacks, do abalone show any response these attacks?

If abalone can be accurately aged, this would be a fundamental tool for more effective management of abalone fisheries.  Several authors have proposed ageing abalone by grinding or cutting abalone shells, and counting the shell layers deposited beneath the spire.  Other authors have cast doubt on this method.  What is uncertain is how reliable these age estimates are.  To construct useful models to assess and manage abalone stocks, it is important to know the accuracy of the data on which the model is based.  Furthermore, it is labour intensive to collect age data, and if these data are very inaccurate, then resources are wasted in collecting it.

This project aimed to find out how reliable and accurate the ageing method was, by investigating the timing and the periodicity of layer formation in abalone shells. It seemed possible that the ageing method might work reasonably in some areas, but not in others.  Thus we planned to repeat the work at many places in the hope that we could predict where ageing would be useful for managing the blacklip and greenlip abalone fisheries of Victoria, Tasmania, New South Wales and South Australia.

Ionoluminescence (IL) combined with particle induced X-ray emission (PIXE) imaging has been employed to identify intrinsic growth bands in the spire region, and extrinsic bands at the growth edge of Australian Black-lip abalone shell (Haliotis rubra). Previous studies using optical flood cathodoluminescence, scanning electron microscope cathodoluminescence (SEM-CL) and Raman spectroscopy on samples from the same population suggest that the visible luminescence is due to Mn²⁺ activated calcium carbonate. In this study we confirm Mn²⁺ as the activator in both the spire and growth edge regions of the shell.

Boring predators and epibionts often damage the shells of molluscs. In abalone, spionid polychaete worms bore holes into the shell and live within the shell matrix (Shepherd and Huchette, 1997). Shepherd and Huchette (1997) found that these worms can infest entire populations, severely weakening the shells of some individuals which can lead to mortality. Given the potential consequences of boring attacks, do abalone show any response these attacks?

If abalone can be accurately aged, this would be a fundamental tool for more effective management of abalone fisheries.  Several authors have proposed ageing abalone by grinding or cutting abalone shells, and counting the shell layers deposited beneath the spire.  Other authors have cast doubt on this method.  What is uncertain is how reliable these age estimates are.  To construct useful models to assess and manage abalone stocks, it is important to know the accuracy of the data on which the model is based.  Furthermore, it is labour intensive to collect age data, and if these data are very inaccurate, then resources are wasted in collecting it.

This project aimed to find out how reliable and accurate the ageing method was, by investigating the timing and the periodicity of layer formation in abalone shells. It seemed possible that the ageing method might work reasonably in some areas, but not in others.  Thus we planned to repeat the work at many places in the hope that we could predict where ageing would be useful for managing the blacklip and greenlip abalone fisheries of Victoria, Tasmania, New South Wales and South Australia.

Ionoluminescence (IL) combined with particle induced X-ray emission (PIXE) imaging has been employed to identify intrinsic growth bands in the spire region, and extrinsic bands at the growth edge of Australian Black-lip abalone shell (Haliotis rubra). Previous studies using optical flood cathodoluminescence, scanning electron microscope cathodoluminescence (SEM-CL) and Raman spectroscopy on samples from the same population suggest that the visible luminescence is due to Mn²⁺ activated calcium carbonate. In this study we confirm Mn²⁺ as the activator in both the spire and growth edge regions of the shell.

Boring predators and epibionts often damage the shells of molluscs. In abalone, spionid polychaete worms bore holes into the shell and live within the shell matrix (Shepherd and Huchette, 1997). Shepherd and Huchette (1997) found that these worms can infest entire populations, severely weakening the shells of some individuals which can lead to mortality. Given the potential consequences of boring attacks, do abalone show any response these attacks?

If abalone can be accurately aged, this would be a fundamental tool for more effective management of abalone fisheries.  Several authors have proposed ageing abalone by grinding or cutting abalone shells, and counting the shell layers deposited beneath the spire.  Other authors have cast doubt on this method.  What is uncertain is how reliable these age estimates are.  To construct useful models to assess and manage abalone stocks, it is important to know the accuracy of the data on which the model is based.  Furthermore, it is labour intensive to collect age data, and if these data are very inaccurate, then resources are wasted in collecting it.

This project aimed to find out how reliable and accurate the ageing method was, by investigating the timing and the periodicity of layer formation in abalone shells. It seemed possible that the ageing method might work reasonably in some areas, but not in others.  Thus we planned to repeat the work at many places in the hope that we could predict where ageing would be useful for managing the blacklip and greenlip abalone fisheries of Victoria, Tasmania, New South Wales and South Australia.

Ionoluminescence (IL) combined with particle induced X-ray emission (PIXE) imaging has been employed to identify intrinsic growth bands in the spire region, and extrinsic bands at the growth edge of Australian Black-lip abalone shell (Haliotis rubra). Previous studies using optical flood cathodoluminescence, scanning electron microscope cathodoluminescence (SEM-CL) and Raman spectroscopy on samples from the same population suggest that the visible luminescence is due to Mn²⁺ activated calcium carbonate. In this study we confirm Mn²⁺ as the activator in both the spire and growth edge regions of the shell.

Boring predators and epibionts often damage the shells of molluscs. In abalone, spionid polychaete worms bore holes into the shell and live within the shell matrix (Shepherd and Huchette, 1997). Shepherd and Huchette (1997) found that these worms can infest entire populations, severely weakening the shells of some individuals which can lead to mortality. Given the potential consequences of boring attacks, do abalone show any response these attacks?

If abalone can be accurately aged, this would be a fundamental tool for more effective management of abalone fisheries.  Several authors have proposed ageing abalone by grinding or cutting abalone shells, and counting the shell layers deposited beneath the spire.  Other authors have cast doubt on this method.  What is uncertain is how reliable these age estimates are.  To construct useful models to assess and manage abalone stocks, it is important to know the accuracy of the data on which the model is based.  Furthermore, it is labour intensive to collect age data, and if these data are very inaccurate, then resources are wasted in collecting it.

This project aimed to find out how reliable and accurate the ageing method was, by investigating the timing and the periodicity of layer formation in abalone shells. It seemed possible that the ageing method might work reasonably in some areas, but not in others.  Thus we planned to repeat the work at many places in the hope that we could predict where ageing would be useful for managing the blacklip and greenlip abalone fisheries of Victoria, Tasmania, New South Wales and South Australia.

Ionoluminescence (IL) combined with particle induced X-ray emission (PIXE) imaging has been employed to identify intrinsic growth bands in the spire region, and extrinsic bands at the growth edge of Australian Black-lip abalone shell (Haliotis rubra). Previous studies using optical flood cathodoluminescence, scanning electron microscope cathodoluminescence (SEM-CL) and Raman spectroscopy on samples from the same population suggest that the visible luminescence is due to Mn²⁺ activated calcium carbonate. In this study we confirm Mn²⁺ as the activator in both the spire and growth edge regions of the shell.

Boring predators and epibionts often damage the shells of molluscs. In abalone, spionid polychaete worms bore holes into the shell and live within the shell matrix (Shepherd and Huchette, 1997). Shepherd and Huchette (1997) found that these worms can infest entire populations, severely weakening the shells of some individuals which can lead to mortality. Given the potential consequences of boring attacks, do abalone show any response these attacks?

If abalone can be accurately aged, this would be a fundamental tool for more effective management of abalone fisheries.  Several authors have proposed ageing abalone by grinding or cutting abalone shells, and counting the shell layers deposited beneath the spire.  Other authors have cast doubt on this method.  What is uncertain is how reliable these age estimates are.  To construct useful models to assess and manage abalone stocks, it is important to know the accuracy of the data on which the model is based.  Furthermore, it is labour intensive to collect age data, and if these data are very inaccurate, then resources are wasted in collecting it.

This project aimed to find out how reliable and accurate the ageing method was, by investigating the timing and the periodicity of layer formation in abalone shells. It seemed possible that the ageing method might work reasonably in some areas, but not in others.  Thus we planned to repeat the work at many places in the hope that we could predict where ageing would be useful for managing the blacklip and greenlip abalone fisheries of Victoria, Tasmania, New South Wales and South Australia.

Ionoluminescence (IL) combined with particle induced X-ray emission (PIXE) imaging has been employed to identify intrinsic growth bands in the spire region, and extrinsic bands at the growth edge of Australian Black-lip abalone shell (Haliotis rubra). Previous studies using optical flood cathodoluminescence, scanning electron microscope cathodoluminescence (SEM-CL) and Raman spectroscopy on samples from the same population suggest that the visible luminescence is due to Mn²⁺ activated calcium carbonate. In this study we confirm Mn²⁺ as the activator in both the spire and growth edge regions of the shell.

Boring predators and epibionts often damage the shells of molluscs. In abalone, spionid polychaete worms bore holes into the shell and live within the shell matrix (Shepherd and Huchette, 1997). Shepherd and Huchette (1997) found that these worms can infest entire populations, severely weakening the shells of some individuals which can lead to mortality. Given the potential consequences of boring attacks, do abalone show any response these attacks?

If abalone can be accurately aged, this would be a fundamental tool for more effective management of abalone fisheries.  Several authors have proposed ageing abalone by grinding or cutting abalone shells, and counting the shell layers deposited beneath the spire.  Other authors have cast doubt on this method.  What is uncertain is how reliable these age estimates are.  To construct useful models to assess and manage abalone stocks, it is important to know the accuracy of the data on which the model is based.  Furthermore, it is labour intensive to collect age data, and if these data are very inaccurate, then resources are wasted in collecting it.

This project aimed to find out how reliable and accurate the ageing method was, by investigating the timing and the periodicity of layer formation in abalone shells. It seemed possible that the ageing method might work reasonably in some areas, but not in others.  Thus we planned to repeat the work at many places in the hope that we could predict where ageing would be useful for managing the blacklip and greenlip abalone fisheries of Victoria, Tasmania, New South Wales and South Australia.

Ionoluminescence (IL) combined with particle induced X-ray emission (PIXE) imaging has been employed to identify intrinsic growth bands in the spire region, and extrinsic bands at the growth edge of Australian Black-lip abalone shell (Haliotis rubra). Previous studies using optical flood cathodoluminescence, scanning electron microscope cathodoluminescence (SEM-CL) and Raman spectroscopy on samples from the same population suggest that the visible luminescence is due to Mn²⁺ activated calcium carbonate. In this study we confirm Mn²⁺ as the activator in both the spire and growth edge regions of the shell.

Boring predators and epibionts often damage the shells of molluscs. In abalone, spionid polychaete worms bore holes into the shell and live within the shell matrix (Shepherd and Huchette, 1997). Shepherd and Huchette (1997) found that these worms can infest entire populations, severely weakening the shells of some individuals which can lead to mortality. Given the potential consequences of boring attacks, do abalone show any response these attacks?

If abalone can be accurately aged, this would be a fundamental tool for more effective management of abalone fisheries.  Several authors have proposed ageing abalone by grinding or cutting abalone shells, and counting the shell layers deposited beneath the spire.  Other authors have cast doubt on this method.  What is uncertain is how reliable these age estimates are.  To construct useful models to assess and manage abalone stocks, it is important to know the accuracy of the data on which the model is based.  Furthermore, it is labour intensive to collect age data, and if these data are very inaccurate, then resources are wasted in collecting it.

This project aimed to find out how reliable and accurate the ageing method was, by investigating the timing and the periodicity of layer formation in abalone shells. It seemed possible that the ageing method might work reasonably in some areas, but not in others.  Thus we planned to repeat the work at many places in the hope that we could predict where ageing would be useful for managing the blacklip and greenlip abalone fisheries of Victoria, Tasmania, New South Wales and South Australia.

Ionoluminescence (IL) combined with particle induced X-ray emission (PIXE) imaging has been employed to identify intrinsic growth bands in the spire region, and extrinsic bands at the growth edge of Australian Black-lip abalone shell (Haliotis rubra). Previous studies using optical flood cathodoluminescence, scanning electron microscope cathodoluminescence (SEM-CL) and Raman spectroscopy on samples from the same population suggest that the visible luminescence is due to Mn²⁺ activated calcium carbonate. In this study we confirm Mn²⁺ as the activator in both the spire and growth edge regions of the shell.

Boring predators and epibionts often damage the shells of molluscs. In abalone, spionid polychaete worms bore holes into the shell and live within the shell matrix (Shepherd and Huchette, 1997). Shepherd and Huchette (1997) found that these worms can infest entire populations, severely weakening the shells of some individuals which can lead to mortality. Given the potential consequences of boring attacks, do abalone show any response these attacks?

If abalone can be accurately aged, this would be a fundamental tool for more effective management of abalone fisheries.  Several authors have proposed ageing abalone by grinding or cutting abalone shells, and counting the shell layers deposited beneath the spire.  Other authors have cast doubt on this method.  What is uncertain is how reliable these age estimates are.  To construct useful models to assess and manage abalone stocks, it is important to know the accuracy of the data on which the model is based.  Furthermore, it is labour intensive to collect age data, and if these data are very inaccurate, then resources are wasted in collecting it.

This project aimed to find out how reliable and accurate the ageing method was, by investigating the timing and the periodicity of layer formation in abalone shells. It seemed possible that the ageing method might work reasonably in some areas, but not in others.  Thus we planned to repeat the work at many places in the hope that we could predict where ageing would be useful for managing the blacklip and greenlip abalone fisheries of Victoria, Tasmania, New South Wales and South Australia.

Ionoluminescence (IL) combined with particle induced X-ray emission (PIXE) imaging has been employed to identify intrinsic growth bands in the spire region, and extrinsic bands at the growth edge of Australian Black-lip abalone shell (Haliotis rubra). Previous studies using optical flood cathodoluminescence, scanning electron microscope cathodoluminescence (SEM-CL) and Raman spectroscopy on samples from the same population suggest that the visible luminescence is due to Mn²⁺ activated calcium carbonate. In this study we confirm Mn²⁺ as the activator in both the spire and growth edge regions of the shell.

Boring predators and epibionts often damage the shells of molluscs. In abalone, spionid polychaete worms bore holes into the shell and live within the shell matrix (Shepherd and Huchette, 1997). Shepherd and Huchette (1997) found that these worms can infest entire populations, severely weakening the shells of some individuals which can lead to mortality. Given the potential consequences of boring attacks, do abalone show any response these attacks?

If abalone can be accurately aged, this would be a fundamental tool for more effective management of abalone fisheries.  Several authors have proposed ageing abalone by grinding or cutting abalone shells, and counting the shell layers deposited beneath the spire.  Other authors have cast doubt on this method.  What is uncertain is how reliable these age estimates are.  To construct useful models to assess and manage abalone stocks, it is important to know the accuracy of the data on which the model is based.  Furthermore, it is labour intensive to collect age data, and if these data are very inaccurate, then resources are wasted in collecting it.

This project aimed to find out how reliable and accurate the ageing method was, by investigating the timing and the periodicity of layer formation in abalone shells. It seemed possible that the ageing method might work reasonably in some areas, but not in others.  Thus we planned to repeat the work at many places in the hope that we could predict where ageing would be useful for managing the blacklip and greenlip abalone fisheries of Victoria, Tasmania, New South Wales and South Australia.

Ionoluminescence (IL) combined with particle induced X-ray emission (PIXE) imaging has been employed to identify intrinsic growth bands in the spire region, and extrinsic bands at the growth edge of Australian Black-lip abalone shell (Haliotis rubra). Previous studies using optical flood cathodoluminescence, scanning electron microscope cathodoluminescence (SEM-CL) and Raman spectroscopy on samples from the same population suggest that the visible luminescence is due to Mn²⁺ activated calcium carbonate. In this study we confirm Mn²⁺ as the activator in both the spire and growth edge regions of the shell.

Boring predators and epibionts often damage the shells of molluscs. In abalone, spionid polychaete worms bore holes into the shell and live within the shell matrix (Shepherd and Huchette, 1997). Shepherd and Huchette (1997) found that these worms can infest entire populations, severely weakening the shells of some individuals which can lead to mortality. Given the potential consequences of boring attacks, do abalone show any response these attacks?

The large starfish, Coscinasterias calamaria is known to feed on commercially exploited molluscs, including blacklip abalone (Haliotis rubra), mussels (Mytilus edulis) and scallops (Pecten irradians).

The study investigated the abundance of the seastar on reefs in Port Phillip Bay, and the extent to which it reduces stocks of the blacklip abalone on these reefs. It is recommended that abalone divers note when there appear to be very few small mussels on offshore reefs early in the year, as this may provide a warning of possible depletion of abalone stocks later. Preventative measures could then be taken.

The large starfish, Coscinasterias calamaria is known to feed on commercially exploited molluscs, including blacklip abalone (Haliotis rubra), mussels (Mytilus edulis) and scallops (Pecten irradians).

The study investigated the abundance of the seastar on reefs in Port Phillip Bay, and the extent to which it reduces stocks of the blacklip abalone on these reefs. It is recommended that abalone divers note when there appear to be very few small mussels on offshore reefs early in the year, as this may provide a warning of possible depletion of abalone stocks later. Preventative measures could then be taken.

The large starfish, Coscinasterias calamaria is known to feed on commercially exploited molluscs, including blacklip abalone (Haliotis rubra), mussels (Mytilus edulis) and scallops (Pecten irradians).

The study investigated the abundance of the seastar on reefs in Port Phillip Bay, and the extent to which it reduces stocks of the blacklip abalone on these reefs. It is recommended that abalone divers note when there appear to be very few small mussels on offshore reefs early in the year, as this may provide a warning of possible depletion of abalone stocks later. Preventative measures could then be taken.

The large starfish, Coscinasterias calamaria is known to feed on commercially exploited molluscs, including blacklip abalone (Haliotis rubra), mussels (Mytilus edulis) and scallops (Pecten irradians).

The study investigated the abundance of the seastar on reefs in Port Phillip Bay, and the extent to which it reduces stocks of the blacklip abalone on these reefs. It is recommended that abalone divers note when there appear to be very few small mussels on offshore reefs early in the year, as this may provide a warning of possible depletion of abalone stocks later. Preventative measures could then be taken.

The large starfish, Coscinasterias calamaria is known to feed on commercially exploited molluscs, including blacklip abalone (Haliotis rubra), mussels (Mytilus edulis) and scallops (Pecten irradians).

The study investigated the abundance of the seastar on reefs in Port Phillip Bay, and the extent to which it reduces stocks of the blacklip abalone on these reefs. It is recommended that abalone divers note when there appear to be very few small mussels on offshore reefs early in the year, as this may provide a warning of possible depletion of abalone stocks later. Preventative measures could then be taken.

The large starfish, Coscinasterias calamaria is known to feed on commercially exploited molluscs, including blacklip abalone (Haliotis rubra), mussels (Mytilus edulis) and scallops (Pecten irradians).

The study investigated the abundance of the seastar on reefs in Port Phillip Bay, and the extent to which it reduces stocks of the blacklip abalone on these reefs. It is recommended that abalone divers note when there appear to be very few small mussels on offshore reefs early in the year, as this may provide a warning of possible depletion of abalone stocks later. Preventative measures could then be taken.

The large starfish, Coscinasterias calamaria is known to feed on commercially exploited molluscs, including blacklip abalone (Haliotis rubra), mussels (Mytilus edulis) and scallops (Pecten irradians).

The study investigated the abundance of the seastar on reefs in Port Phillip Bay, and the extent to which it reduces stocks of the blacklip abalone on these reefs. It is recommended that abalone divers note when there appear to be very few small mussels on offshore reefs early in the year, as this may provide a warning of possible depletion of abalone stocks later. Preventative measures could then be taken.

The large starfish, Coscinasterias calamaria is known to feed on commercially exploited molluscs, including blacklip abalone (Haliotis rubra), mussels (Mytilus edulis) and scallops (Pecten irradians).

The study investigated the abundance of the seastar on reefs in Port Phillip Bay, and the extent to which it reduces stocks of the blacklip abalone on these reefs. It is recommended that abalone divers note when there appear to be very few small mussels on offshore reefs early in the year, as this may provide a warning of possible depletion of abalone stocks later. Preventative measures could then be taken.

The large starfish, Coscinasterias calamaria is known to feed on commercially exploited molluscs, including blacklip abalone (Haliotis rubra), mussels (Mytilus edulis) and scallops (Pecten irradians).

The study investigated the abundance of the seastar on reefs in Port Phillip Bay, and the extent to which it reduces stocks of the blacklip abalone on these reefs. It is recommended that abalone divers note when there appear to be very few small mussels on offshore reefs early in the year, as this may provide a warning of possible depletion of abalone stocks later. Preventative measures could then be taken.

The large starfish, Coscinasterias calamaria is known to feed on commercially exploited molluscs, including blacklip abalone (Haliotis rubra), mussels (Mytilus edulis) and scallops (Pecten irradians).

The study investigated the abundance of the seastar on reefs in Port Phillip Bay, and the extent to which it reduces stocks of the blacklip abalone on these reefs. It is recommended that abalone divers note when there appear to be very few small mussels on offshore reefs early in the year, as this may provide a warning of possible depletion of abalone stocks later. Preventative measures could then be taken.

The large starfish, Coscinasterias calamaria is known to feed on commercially exploited molluscs, including blacklip abalone (Haliotis rubra), mussels (Mytilus edulis) and scallops (Pecten irradians).

The study investigated the abundance of the seastar on reefs in Port Phillip Bay, and the extent to which it reduces stocks of the blacklip abalone on these reefs. It is recommended that abalone divers note when there appear to be very few small mussels on offshore reefs early in the year, as this may provide a warning of possible depletion of abalone stocks later. Preventative measures could then be taken.

The large starfish, Coscinasterias calamaria is known to feed on commercially exploited molluscs, including blacklip abalone (Haliotis rubra), mussels (Mytilus edulis) and scallops (Pecten irradians).

The study investigated the abundance of the seastar on reefs in Port Phillip Bay, and the extent to which it reduces stocks of the blacklip abalone on these reefs. It is recommended that abalone divers note when there appear to be very few small mussels on offshore reefs early in the year, as this may provide a warning of possible depletion of abalone stocks later. Preventative measures could then be taken.

The large starfish, Coscinasterias calamaria is known to feed on commercially exploited molluscs, including blacklip abalone (Haliotis rubra), mussels (Mytilus edulis) and scallops (Pecten irradians).

The study investigated the abundance of the seastar on reefs in Port Phillip Bay, and the extent to which it reduces stocks of the blacklip abalone on these reefs. It is recommended that abalone divers note when there appear to be very few small mussels on offshore reefs early in the year, as this may provide a warning of possible depletion of abalone stocks later. Preventative measures could then be taken.

The large starfish, Coscinasterias calamaria is known to feed on commercially exploited molluscs, including blacklip abalone (Haliotis rubra), mussels (Mytilus edulis) and scallops (Pecten irradians).

The study investigated the abundance of the seastar on reefs in Port Phillip Bay, and the extent to which it reduces stocks of the blacklip abalone on these reefs. It is recommended that abalone divers note when there appear to be very few small mussels on offshore reefs early in the year, as this may provide a warning of possible depletion of abalone stocks later. Preventative measures could then be taken.

The large starfish, Coscinasterias calamaria is known to feed on commercially exploited molluscs, including blacklip abalone (Haliotis rubra), mussels (Mytilus edulis) and scallops (Pecten irradians).

The study investigated the abundance of the seastar on reefs in Port Phillip Bay, and the extent to which it reduces stocks of the blacklip abalone on these reefs. It is recommended that abalone divers note when there appear to be very few small mussels on offshore reefs early in the year, as this may provide a warning of possible depletion of abalone stocks later. Preventative measures could then be taken.

The large starfish, Coscinasterias calamaria is known to feed on commercially exploited molluscs, including blacklip abalone (Haliotis rubra), mussels (Mytilus edulis) and scallops (Pecten irradians).

The study investigated the abundance of the seastar on reefs in Port Phillip Bay, and the extent to which it reduces stocks of the blacklip abalone on these reefs. It is recommended that abalone divers note when there appear to be very few small mussels on offshore reefs early in the year, as this may provide a warning of possible depletion of abalone stocks later. Preventative measures could then be taken.