Offshore killer whale (Orcinus orca) management plan: chapter 2

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2.0 Management

2.1 Goal

To maintain a population level that is viable over the long-term within the known range for the northeastern Pacific Offshore Killer Whale population in Pacific waters of Canada
As uncertainty surrounding population abundance and general biology is high, a conservative approach is warranted, and the need to address knowledge gaps should be recognized in order to meet this goal.  As this population moves between U.S. and Canadian waters, the role of Canadian management will aim to protect the population within Canada and contribute to research and conservation initiatives in the U.S., where feasible.

2.2 Objectives

Over the next ten years, the population and distribution objectives are to:

• P1: Maintain the population at, or above its current level (averaged over 5 years)
• D1: Maintain the population’s current range of occupancy and distribution on the west coast of B.C.

At present, many uncertainties remain regarding Offshore Killer Whale demographics and distribution.  However, a preliminary population census (DFO-CRP unpublished data) and sightings data have provided an initial estimate of 288 animals in this population, with members found throughout British Columbia’s marine waters.  Given that these data are preliminary, specific, quantitative population and distribution objectives in terms of increasing population size or distribution are not feasible at this time.  A complementary research objective (R4) to determine levels of human-caused mortality that will not impede achievement of the population objective (P1) will assist in providing a benchmark to gauge the actual levels of anthropogenic mortality.  Maintenance of current estimated population level and distribution are at present the most biologically-defensible objectives.  From a Canadian management perspective, maintenance of distribution and population levels in B.C. waters is a priority.

Research and Monitoring Objectives:

Over the next ten years, research objectives are to:

• R1: Complete numeric census of the population, and monitor demographics
• R2: Support, foster and contribute to the clarification of general aspects of the biology and ecological role of Offshore Killer Whales in Canada.  Of particular importance are studies on foraging ecology, population abundance, and seasonal occurrence
• R3: Support, foster and contribute to research addressing knowledge gaps regarding effects of entanglement, chemical and biological pollutants, and effects of other identified (Table 2) and non-identified threats to this population
• R4: Assess available methods and estimate levels of annual human-caused mortality that the population can sustain and achieve objective P1

Significant knowledge gaps remain regarding general biology of Offshores, and addressing these knowledge gaps will aid in directing management efforts.  Objective R1 will provide information on an ongoing basis in order to monitor population health, while R2 and R3 will address uncertainties on threats to the population. An estimate of the level of human-caused mortality that will not jeopardize achieving objective P1, may provide a measure against which to assess the impact of threats.  Efforts to monitor anthropogenic-related mortalities may assist in determining impacts of specific threats on this population.  As there are general ecological questions regarding Offshore Killer Whales, research to address these uncertainties is considered a higher priority at this time.  Canadian research efforts will focus on the population within British Columbian waters, while collaboration with U.S. researchers will contribute to the body of knowledge on Offshores in the larger context (i.e. on the west coast of North America).  Over a ten year period, questions regarding the ecological role of this population must be answered in order to support the described goal. 

Management Objectives:

Over the next ten years, management objectives are to:

• M1 To reduce the risk of catastrophic spills impacting the Offshore Killer Whale population in B.C.
• M2 Minimize exposure of Offshore Killer Whales to biological and chemical pollutants
• M3 Minimize the exposure of Offshore Killer Whales to acute or chronic sound levels in excess of those considered to cause behavioural or physical harm in cetaceans
• M4 Minimize the degradation of realized, and potential habitat within Canada
• M5 Promote and contribute to international collaboration, independent research, education and outreach on management and conservation initiatives

Management objectives address threats rated at medium or high level of concern (Table 2) to prevent population decline and achieve the management goal (Section 2.1).  Catastrophic toxic spills, prey reduction, contamination and acute noise were assessed to be the top threats to these whales (Table 2).  As these whales are a trans-boundary population, education and collaboration with U.S. managers and researchers will aid in conservation and mitigation efforts.

Threats assessed at low or unknown levels of concern (Table 2) do not have direct objectives; instead knowledge gaps will be filled by opportunistic or cost-effective means, where feasible.  Effects of some threats impact individual whales, but do not constitute a population level effect.  Where mitigation feasibility is high (Table 2) and resources are available it is prudent to manage and mitigate these threats.

2.3 Actions

The primary focus of this management plan is to recommend actions to close knowledge gaps and identify research needs to increase our understanding of the Offshore Killer Whale population.  Despite uncertainty regarding species biology, management actions that may reduce the risk of population-level effects of threats should be undertaken.  The ability of DFO to undertake and/or support the actions identified will be subject to the availability of required funding and other resources.

The following actions (not listed in order of priority) are recommended to support management goals and objectives outlined in Sections 2.1 and 2.2 in order to prevent Offshores from becoming listed as threatened or endangered.  Many of the actions listed below are currently underway (see Section 1.6 ‘Actions already completed, or underway’), and are identified in other recovery planning documents to date (See Section 4 ‘Associated Plans’).  The synchronization of these listed activities for protection, management and research will facilitate a multi-species approach to marine mammal conservation in British Columbia, and allow for effective use of available resources.  Actions have been recommended where implementation is deemed to be practical and feasible, and those most likely to result in successful protection of the Offshore Killer Whale population in B.C.

Where responsibility is determined to fall under Fisheries and Oceans Canada jurisdiction, these actions will be implemented directly though collaboration with other responsible agencies and organizations, and successful coordination of efforts may be necessary in some cases to complete actions.  If responsibility for actions falls outside of the mandate of Fisheries and Oceans Canada, or outside of its jurisdiction, support for implementation of the action(s) and contribution to effort(s) will be a priority, where feasible.  Participating agencies and organizations and implementation timelines for each of the listed actions are presented in Table 4.  Organizations currently involved in data collection on Offshore Killer Whales are listed in Appendix II.

2.3.1 Protection

• Continue to protect Offshore Killer Whales from acute acoustic disturbance to effectively mitigate potential negative population level effects.
  • Apply the Fisheries and Oceans Canada Statement of Canadian Practice with respect to the Mitigation of Seismic Sound in the Marine Environment (DFO 2005) as well as associated regional implementation protocols to increase effectiveness in mitigation of seismic noise stress with respect to Killer Whales.
  • Request Fisheries and Oceans Canada engagement with Department of National Defence to update on changes to the ‘Maritime Command Order: Marine Mammal Mitigation Procedures’ and any new information to ensure effectiveness in minimizing impacts of tactical sonar noise on marine mammals.
• To protect Offshore Killer Whales from physical disturbance, vessel interactions and chronic noise stress.
  • Complete Marine Mammal Regulation [MMR] amendments under theFisheries Act to reduce the risk of displacement from habitat, collisions with vessels, entanglement in gear, and the effects of acoustic disturbance.⁵
  • Continue enforcement of MMR and regional guidelines for marine mammal viewing, as well as relevant regulations for marine industrial development.

2.3.2 Management

• Continue to review project proposals that include generation of acute noise (such as seismic and sonar surveying) and provide project-specific advice for mitigation or avoidance.
• Manage and reduce input of chemicals into habitat to reduce toxic loading in Offshore Killer Whales, their habitat and prey species.
  • Develop marine mammal-specific measures for inclusion into catastrophic spill response programs,
    • Develop an emergency response plan to identify marine mammal expertise required in spill response initiatives, when triggered.
    • Develop a marine mammal-specific operational manual to be included into existing catastrophic spill response plan(s)⁶to identify data collection and response protocols required for mitigation of short and long-term effects to marine mammals and habitat.
  • Review and routinely monitor point-source contamination in known Offshore Killer Whale habitat in B.C.
    • Review management of point-sources of toxic pollution to assess relevancy of current federal, provincial, and regional guidelines for thresholds for environmental contamination for specific chemicals listed in Appendix I, in terms of potential effects to Offshore Killer Whales.
    • Routinely monitor these point-sources to assess compliance with federal, provincial, and regional guidelines regarding thresholds for environmental contamination for the specific chemicals listed in Appendix I.
• Continue the permitting of non-DFO research programs, monitoring and assessment (Sections 2.3.3 and 2.3.4) to address key knowledge gaps and clarify identified threats.  This action will continue to support actions 9a through e, 10, 11a to c, and 12a to c.
• Support the Marine Mammal Response Network, to facilitate standardized sample collection and necropsy of carcasses, and for collection and sharing of data to support a comprehensive understanding of identified threats catastrophic spills, noise and physical disturbance, vessel collisions, entanglement, entrapment and mass stranding.  This action will support that listed in 12a.
• Strengthen, support and foster, where feasible, the continued development of fisheries observer reporting standards and guidelines for marine mammal species identification and data collection to clarify the extent of fisheries interactions (i.e. entanglement, by-catch) and gather samples, where possible.  This action would support actions 6, and 12b, where appropriate.
• Once knowledge gaps regarding prey and dietary needs for Offshore Killer Whales in B.C. are addressed, update integrated fishery management plan(s) for relevant species to recognize the foraging requirements of these whales.

2.3.3 Research on Offshore Killer Whale Biology

• The priority of this management plan is to outline research actions needed to increase our knowledge of Offshore Killer Whales in B.C. and on the west coast of North America.  Opportunistic data collection and multi-species research programs may be combined to provide a more cost-effective means of achieving research goals outlined in this management plan and others, including recovery strategies and action plans (See Section 4.0 ‘Associated Plans’).  The following information on life history parameters of Offshore Killer Whales are prioritized by order of importance in addressing knowledge gaps for this population.
  • Conduct annual ship-based, multi-species marine mammal reconnaissance surveys.  Complement ship-based surveys with aerial surveys, where and when feasible. This action will assist in determination of distribution, range and seasonal occurrence of Offshore Killer Whales within B.C., and provide capacity to carry out actions 9b through 9e.
  • Continue the sight-resight (photo-identification) program on Killer Whales to contribute to data for total population census, and allow for monitoring of population abundance, long-term trends, and demographics of Offshore Killer Whales.
  • Deploy remote acoustic monitoring packages annually to gauge the seasonal occurrence of Offshore Killer Whales in key areas of the B.C. coast.
  • Conduct field sampling to identify the foraging ecology and diet of Offshore Killer Whales to support further understanding and monitoring of effects of prey limitation. 
  • Collect tissue samples from both Offshore Killer Whales and potential prey species, when feasible, to contribute to the determination of pathogen and pollutant profiles, and potential prey species.  This action will complement that listed in 9d, and may be supported by action 12a, when appropriate.

2.3.4 Monitoring and Assessment

The population, as well as identified threats should be monitored on a long-term scale in order to gauge effectiveness of management of threats, as well as to prevent increases in stress to the population.  Where effects of threats are unknown, effort should be focused to gathering additional data to address uncertainties.  Such monitoring could also include identification and sampling at sources or vectors of stress. 

• Support efforts to monitor the distribution and occurrence of Killer Whales in B.C. to support research efforts.
• Conduct ongoing assessments of the vulnerability of Offshore Killer Whales to identified threats, as this population’s distribution is further identified.
• Evaluate the need for risk assessment models (e.g. Barlow and Gisiner, 2006) to ascertain risk factors for toxic spills, vessel strikes, entanglement in fishing gear, exposure to biological pollutants, and prey limitation on Offshore Killer Whales and/or their habitat in B.C. and range-wide. Actions 5 and 13c will contribute to this effort.
• Investigate the potential for increased risk of seismic noise stress, catastrophic spills and vessel disturbance to the Offshore Killer Whale population that might result from lifting the moratorium on offshore fossil fuel exploration and extraction in B.C.  Action 13c will contribute to this effort.
• Assess the likelihood of population level impacts from prey limitation on Offshore Killer Whales.  This action is contingent upon results from 9d and 9e.
• Clarify the extent of threats to the Offshore Killer Whale population.
• Perform necropsy of carcasses, where feasible, to determine pathogen loading.  This action may assist 9e and action 6 will assist in providing capacity.
• Assess the potential for Offshore Killer Whale fisheries interactions, through depredation, entanglement in gear, or through competition for resources (i.e. prey).  Action 7 will provide some capacity, and results from 9d and 9e may be required to evaluate potential competition for resources.
• Evaluate the feasibility of conducting an assessment of current sources of biological pollutants within known Offshore Killer Whale habitat to assess the potential for population-level impacts to the population.  This action may be conducted in concert with action 4b where appropriate, or feasible.

2.3.5 Outreach and Communication

• Foster improved communication networks to increase awareness of Offshore Killer Whale initiatives.
  • Pro-actively build intra- and interagency networks for effective communication during catastrophic spill response to allow timely, effective and coordinated actions by responsible agencies and parties.  This action will support 4a.
  • Ongoing media communications, outreach and promotion of the Marine Mammal Regulation and ‘Be Whale Wise: Marine Wildlife Guidelines for Boaters, Paddlers and Viewers’ to reduce physical and acoustic disturbance.
  • Support and contribute, where feasible, to trans-boundary and inter-jurisdictional collaboration on research and management initiatives to ensure a coordinated response to conservation of this population. This effort will assist and support all actions listed.

⁵ To view the proposed amendments to the Marine Mammal Regulation, visit http://www-comm.pac.dfo-mpo.gc.ca/pages/consultations/marinemammals/mmr-update_e.htm

⁶ Include in the operational manual, measures outlined in the Fisheries and Oceans Canada ‘Marine mammal incident response’ manual (draft) and ‘Sea otter oil spill response plan for Canada’s Pacific coast’ (working document).