Chapter 12: Conclusions
Restoring a population of sea otters on the Oregon coast is feasible if steps are taken to account for ecological, habitat, logistic, economic, and social factors highlighted in this Feasibility Study. There appear to be no insurmountable ecological, habitat, physiological, logistical, or regulatory barriers to restoring a population of sea otters in Oregon.
- Reintroductions are a successful conservation tool.
The reintroduction (through translocation) of sea otters has been the most important management action contributing to the species’ recovery from near extinction in regions of the eastern North Pacific. Approximately 30% of global sea otter abundance can be attributed to reintroductions to Southeast Alaska, British Columbia, and Washington. Reintroductions have increased species viability, helped recover genetic diversity, and improved gene flow in sea otter populations. Previous reintroductions, even those that failed, can provide practical and logistical lessons that will improve the chances of success.
- Reintroducing sea otters to Oregon is likely to succeed, with appropriate considerations.
A spatially explicit population model developed specifically for evaluating potential sea otter reintroductions to Oregon shows that a reintroduced population (or populations) of sea otters is likely to be viable, assuming sufficient numbers of animals are released to appropriate habitats. When combined with an analysis of habitat suitability, this model suggests several areas (mostly along the southern coast) that would likely support a successful reintroduction. The model also indicates that multiple release locations may be more effective than a single release site. The population model used in the Feasibility Study can guide alternate reintroduction strategies, including determining appropriate numbers, demographic structure, sequencing, and location of reintroduced populations.
- Estuaries may be an important reintroduction environment.
In addition to nearshore ocean habitats, several estuaries in Oregon may offer suitable habitat for a founding sea otter population. Use of estuarine release sites could increase the potential for successful establishment of a population center, especially when close to suitable nearshore ocean habitat (e.g., Coos Bay or Yaquina Bay).
- Return of sea otters will have many direct and indirect effects.
As a keystone species, sea otters have inordinately strong effects on the nearshore ecosystems they inhabit. Impacts associated with sea otter recovery include both direct effects on prey species some of which, such as Dungeness crab, currently support commercially-important fisheries as well as indirect effects throughout the nearshore or estuarine environment mediated through ecological interactions. Many of the indirect ecosystem effects are beneficial, including
increases in kelp forests and eelgrass beds that, in turn increase finfish and invertebrate species that rely on kelp and eelgrass, increase overall biodiversity, and productivity, and increase in carbon capture and fixation. Impacts of sea otters on some shellfish species can have negative social and economic effects.
- Social, economic factors and regulatory issues must be considered.
Reintroductions of sea otters can only occur if socioeconomic and regulatory issues are fully addressed. Outreach and engagement with a broad array of affected stakeholders are essential to ensuring that decisions about reintroductions have considered all the relevant factors and have a broad base of support.