Review of the Effectiveness of Recovery Activities for North Atlantic right whales

Conclusions

Table of Contents

• Complete Text
• 1. Background
• 2. Objective of this Review
• 3. Sources of Information
• 4. Methods for Assessing Effectiveness of Recovery activities
• 5. Review of Recovery activities
  • 5.1. Recovery Objectives
  • 5.2. Threats
  • 5.3. Review of Recovery activities
• 6. Effectiveness of Recovery Activities
  • 6.1. Vessel Strikes
  • 6.2. Fishing-Gear Entanglements
  • 6.3. Disturbance and Habitat Reduction or Degradation
    • 6.3.1. Contaminants
    • 6.3.2. Acoustic Disturbance
    • 6.3.3. Vessel-presence disturbance
    • 6.3.4. Changes in Food Supply
• 7. Indirect Recovery Activities: Monitoring and Stewardship
• 8. Threat-Based Recommendations
  • 8.1. Vessel Strikes
  • 8.2. Fishing-Gear Entanglements
  • 8.3. Disturbance and Habitat Reduction or Degradation
  • 8.4. Required Research and Monitoring
• 9. Conclusions
• 10. Literature Cited
• Appendix A: Acronyms
• Appendix B: Defining Risk
• Appendix C: Summaries of Recovery Activities

9. Conclusions

Since the Recovery Strategy was first published in 2009, the observed serious injuries and mortalities of North Atlantic right whales from fishing-gear entanglements appear to be increasing and may be overwhelming recovery efforts (Kraus et al. 2016). Between 1995 and 2009 the average per cent that the PBR (average PBR/year 0.1±0.2 standard deviation) was exceeded by human-induced mortalities per year (3.1±0.5 standard deviation) was 650 (± 379 standard deviation; van der Hoop et al. 2013). Two out of the three population assessment methods used for North Atlantic right whales demonstrate a decline in North Atlantic right whale abundance (Kraus et al. 2016 and references therein), therefore threats to the species collectively have not been sufficiently reduced to allow for continued population growth and the interim recovery goal stated in the Recovery Strategy is not being achieved.

In the Recovery Strategy (DFO 2014), Objectives 1-3 address mortalities, serious injuries, and the health of individual North Atlantic right whales in the population through directly addressing identified threats to the population (Table 1). While important and informative, Objectives 4-7 do not directly reduce threats to individuals in the population, rather they describe approaches that are needed to address the identified threats and thus support the first three objectives. The Progress Report (DFO 2016b) highlights that, to date, the majority of the effort on North Atlantic right whale recovery focuses on Objectives 4-7 rather than direct threat based measures of Objectives 1-3. This highlights the need to refocus recovery efforts to reducing the identified threats to North Atlantic right whales.

The proposed Action Plan is timely and focuses exclusively on fishing-gear entanglements as the majority of recent mortalities and serious injuries have been attributed to this threat. However, this Action Plan does not recommend recovery activities that would remove gear for entanglement prevention and thus reduce the risk of a lethal entanglement. To ensure a healthy population of North Atlantic right whales, the focus should be on preventing entanglement events rather than relying on gear modification and disentanglement efforts. The simplest, most direct and practical means of reducing risk to the North Atlantic right whales would be to remove fishing activities within critical habitats (i.e., spatiotemporal closures; Table 5, Vanderlaan et al. 2011, Brillant et al. 2017). Furthermore, the Action Plan only address one of the identified threats to North Atlantic right whales and further action plans should be developed to address the remaining and any new emerging threats.

Twice members of the scientific community have published reports declaring there is an urgent need for immediate management intervention to reduce human-induced mortalities of North Atlantic right whales (Kraus et al. 2005, 2016). Kraus et al. (2005) address threats from vessel strike and fishing gear, while Kraus et al. (2016) address the threat of fishing gear (Kraus et al. 2016). With only limited recovery of the population over the past several decades and recent declines observed in population health and growth (Kraus et. al. 2016; Rolland et al. 2016; Pace 2016), implementation of recovery activities that will reduce threats to North Atlantic right whales in the short-term is imperative for the long-term survival of this endangered species.