Document ID: chunk:federal_register_of_legislation:F2005L01892:body:0:p7
Version: federal_register_of_legislation:F2005L01892
Segment Type: other
Provision Reference: 
Character Range: 16104–19164

extent of the threat of habitat degradation to these species.

  Habitat degradation may result in reduced occupancy and/or exclusion of individual whales from suitable habitat, compromised reproductive success, and mortality. It is possible that impacts on a sufficient number of individual whales could lead to broader impacts at the population level, e.g. by reducing recruitment to such an extent that species recovery is impeded. This would be more likely to arise where activities that cause habitat degradation occurred intensively and/or cumulatively, or over a large portion of their range.

  Ongoing monitoring and management, particularly in relation to known blue whale aggregation areas, are required to ensure that habitat degradation does not become a significant issue. Further identification of habitat areas important to the survival of all three species is also needed.

Potential threats
   1. Climate and oceanographic change
  Most of the world's leading scientists agree that global warming caused by human activity is occurring. The exact implications of these changes are unknown, but it is predicted that there will be reduced productivity of Southern Ocean ecosystems and unpredictable weather events caused by increasing ocean water temperatures, changing ocean currents, rising sea levels and reductions in sea ice.

  The potential impacts of climate and oceanographic change on blue, fin and sei whales are twofold:
  1)  Habitat availability
    Whale migration, feeding, breeding, and calving site selection for these species may be influenced by factors such as ocean currents and water temperature. Any changes in these factors could affect recovery by rendering currently used habitat areas unsuitable.

  2)  Food availability
    Changes to climate and oceanographic processes may also lead to decreased productivity and different patterns of prey distribution and availability. Such changes would certainly effect dependant predators such as blue, fin and sei whales.

  2.      Prey depletion due to over harvesting
  Blue, fin and sei whales rely on krill as a main food source and require adequate supplies to accumulate energy reserves essential for migration and breeding. Depletion of krill through over harvesting may be a potential future threat for Australian populations of these species. However, it should be noted that:
       * the krill fishery is managed through the Convention on the Conservation of Antarctic Marine Living Resources (CCAMLR) on an ecosystem basis which takes into account the needs of predators such as whales; and
       * while the fishery is likely to grow, fishing currently occurs well within the current precautionary limits.

Actions to achieve the objectives

Population recovery
   1. Implement a program to measure population abundance, trends and recovery for Australian populations of blue, fin and sei whales
       * Included within this activity will be the need to:
              + establish models for measuring the recovery and status of blue whales, incorporating a