New Study Looks to Investigate the Potential Reintroduction of Sea Otters to Oregon

By Dominique Kone, Masters Student in Marine Resource Management

As I begin a new chapter as a grad student in the Marine Resource Management program at Oregon State University, the GEMM Lab is also entering into unchartered waters by expanding its focus to a new species outside the lab’s previous research portfolio. This project – which will be the focus of my thesis – will assess the potential reintroduction of sea otters to the Oregon coast through an examination of available habitat and ecological impacts. Before I explain how this project came to fruition, it’s important to understand why sea otter reintroduction to Oregon is relevant, and why this step is important to advance the conservation of these charismatic species.

While exact historical populations are unknown, sea otters were once abundant along the coasts of northern Japan, across Russia and Alaska, and down North America to Baja California, Mexico[1]. In the United States, specifically, sea otters were native to coastal waters along the entire west coast – including Oregon. However, beginning in the 1740’s sea otters were subject to intense and unsustainable hunting pressure from Russian, British, and American entrepreneurs seeking to sell their highly-valuable pelts in the lucrative fur trade[2].  Historical records suggest these hunters did not arrive in Oregon until the 1780’s, but from that point on the sea otter was exploited over the next several decades until the last known Oregon sea otter was killed in 1906 at Otter Rock, OR[3].

Pictured: Sea otter hunters near Coos Bay, OR in 1856. Photo Credit: The Oregon History Project.

After decades of intense pressure, sea otter numbers dropped to critically low levels and were thought to have gone extinct throughout most of their range. Luckily, remnant populations persisted and were later discovered in parts of Alaska, British Columbia, California, and Mexico beginning in the 1910’s. Since then sea otters have been the focus of intense conservation efforts. With the goal of augmenting their recovery, the Alaska Department of Fish and Game lead a series of translocation projects, where groups of sea otters were transported from Alaska to unoccupied habitats in Alaska, British Columbia, Washington, and Oregon (Note: these were not the only sea otter translocations.)1.

Pictured: Sea otters on glacier ice, northern Prince William Sound, Alaska. Photo Credit: Patrick J. Endres/AlaskaPhotoGraphics.com

Fun Fact: For a marine mammal, sea otters have surprisingly little blubber. Luckily, they also have the densest fur of all animals – an estimated 1,000,000 hairs per square inch – that helps to keep them well-insulated from the cold.

Many of these projects are considered successful as sea otter populations grew, and continue to expand today. With a significant exception: sea otters mysteriously disappeared shortly after reintroduction into Oregon waters and the translocation effort failed. Many hypothesized what could have gone wrong – natural mortality, dispersal, conflicts with humans – but few have concrete answers. Aside from occasional reports of strandings and sightings of sea otters in Oregon coastal waters, no resident populations have formed. This is where my thesis project comes in.

Pictured: Cape Arago, OR – one of the unsuccessful translocation sites along the Oregon coast. Photo Credit: TravelOregon.com

With renewed interests from scientists, tribes, and the public, we are now revisiting this idea from a scientific perspective. Over the next two years, we will work to objectively assess the ecological aspects of sea otter reintroduction to Oregon to identify and fill current knowledge gaps, which will help inform decision-making processes by environmental managers. Throughout this process we will give consideration to not just the ecology and biology of sea otters, but the cultural, economic, and political relevance and implications of sea otter reintroduction. Much of this work will involve working with state and federal agencies, tribes, and other scientists to gain their insights and perspectives, which we will use to shape our research questions and analyses.

The process to move forward with bringing sea otters back to Oregon will no doubt take great effort by a lot of people, consultation, patience, and time. To date, we have been reviewing the relevant literature and meeting with local experts on this topic. Through these activities, we have determined the types of questions and information – suitable habitat and potential ecological impacts – of most need to managers. My goal is to conduct a meaningful, applied project as an objective scientist, and by gaining this type of feedback at the outset, I am to help managers make better-informed decisions. I hope my thesis can serve as a critical starting point to ensure a solid foundation that future Oregon-specific sea otter research can build from.

References:

[1] Jameson et al. 1982. History and status of translocated sea otter populations in North America. Wildlife Society Bulletin. (10) 2: 100-107.

[2] The Oregon History Project: Sea Otter. Accessed September 2017. <https://oregonhistoryproject.org/articles/historical-records/sea-otter/#.WamgT7KGPIU>

[3] The Oregon History Project: Otter Hunting. Accessed September 2017. <https://oregonhistoryproject.org/articles/historical-records/otter-hunting/#.Wa2TCLKGPIU>

 

Understanding How Nature Works

By: Erin Pickett, MS student, Oregon State University

They were climbing on their hands and knees along a high, narrow ridge that was in places only two inches wide. The path, if you could call it that, was layered with sand and loose stones that shifted whenever touched. Down to the left was a steep cliff encrusted with ice that glinted when the sun broke down through the thick clouds. The view to the right, with a 1,000ft drop, wasn’t much better.

The Invention of Nature by Andrea Wulf

This is a description of Alexander von Humboldt and the two men that accompanied him when attempting to summit Chimborazo, which in 1802 was believed to be the highest mountain in the world. The trio was thwarted about 1,000 ft from the top of the peak by an impassable crevice but set a record for the highest any European had ever climbed. This was a scientific expedition. With them the men brought handfuls of scientific instruments and Humboldt identified and recorded every plant and animal species along the way. Humboldt was an explorer, a naturalist, and an observer of everything. He possessed a memory that allowed him to recount details of nature that he had observed on a mountain in Asia, and find patterns and connections between that mountain and another in South America. His perspective of nature as being interconnected, and theories as to why and how this was so, led to him being called the father of Ecology. In less grandeur terms, Humboldt was a biodiversity explainer.

Humboldt sketched detailed images like this one of Chimborazo, which allowed him to map vegetation and climate zones and identify how these and other patterns and processes were related. Source: http://www.mappingthenation.com/blog/alexander-von-humboldt-master-of-infographics/

In a recent guest post on Carbon Brief, University of Connecticut Professor Mark Urban summarized one of his latest publications in the journal Science, and called on scientists to progress from biodiversity explainers to biodiversity forecasters.  Today, as global biodiversity is threatened by climate change, one of our greatest scientific problems has become accurately forecasting the responses of species and ecosystems to climate change. Earlier this month, Urban and his colleagues published a review paper in Science titled “Improving the forecast for biodiversity under climate change”. Many of our current models aimed at predicting species responses to climate change, the authors noted, are missing crucial data that hamper the accuracy and thus the predictive capabilities of these models. What does this mean exactly?

Say we are interested in determining whether current protected areas will continue to benefit the species that exist inside their boundaries over the next century. To do this, we gather basic information about these species: what habitat do they live in, and where will this habitat be located in 100 years? We tally up the number of species currently inhabiting these protected areas, figure out the number of species that will relocate as their preferred habitat shifts (e.g. poleward, or higher in elevation) and then we subtract those species from our count of those who currently exist within the boundaries of this protected area. Voilà, we can now predict that we will lose up to 20% of the species within these protected areas over the next 100 years*.  Now we report our findings to the land managers and environmental groups tasked with conserving these species and we conclude that these protected areas will not be sufficient and they must do more to protect these species. Simple right? It never is.

This predication, like many others, was based on a correlation between these species ranges and climate. So what are we missing? In their review, Urban et al. outline six key factors that are commonly left out of predictive models, and these are: species interactions, dispersal, demography, physiology, evolution and environment (specifically, environment at appropriate spatiotemporal scales) (Figure 1). In fact, they found that more than 75% of models aimed at predicting biological responses to climate change left out these important biological mechanisms. Since my master’s project is centered on species interactions, I will now provide you with a little more information about why this specific mechanism is important, and what we might have overlooked by not including species interactions in the protected area example above.

Figure 1: Six critical biological mechanisms missing from current biodiversity forecasts. Source: Urban et al. 2016
Figure 1: Six critical biological mechanisms missing from current biodiversity forecasts. Source: Urban et al. 2016

I study Adelie and gentoo penguins, two congeneric penguin species whose breeding ranges overlap in a few locations along the Western Antarctic Peninsula. You can read more about my research in previous blog posts like this one. Similar to many other species around the world, both of these penguins are experiencing poleward range shifts due to atmospheric warming. The range of the gentoo penguin is expanding farther south than ever before, while the number of Adelie penguins in these areas is declining rapidly (Figure 2). A correlative model might predict that Adelie penguin populations will continue to decline due to rising temperatures, while gentoo populations will increase. This model doesn’t exactly inform us of the underlying mechanisms behind what we are observing. Are these trends due to habitat shifts? Declines in key prey species? Interspecific competition? If Adelie populations are declining due to increased competition with other krill predators (e.g. gentoo penguins), then any modelling we do to predict future Adelie population trends will certainly need to include this aspect of species interaction.

Figure 2. A subset of the overall range of Adelie and gentoo penguins and their population trends at my study site at Palmer Station 1975-2014. Source: https://www.allaboutbirds.org/on-the-antarctic-peninsula-scientists-witness-a-penguin-revolution/
Figure 2. A subset of the overall range of Adelie and gentoo penguins and their population trends at my study site at Palmer Station 1975-2014. Source: https://www.allaboutbirds.org/on-the-antarctic-peninsula-scientists-witness-a-penguin-revolution/

Range expansion can result in novel or altered species interactions, which ultimately can affect entire ecosystems. Our prediction above that 20% of species within protected areas will be lost due to habitat shifts does not take species interactions into account. While some species may move out of these areas, others may move in. These new species may potentially outcompete those who remain, resulting in a net loss of species larger than originally predicted. Urban et al. outline the type of data needed to improve the accuracy of predictive models. They openly recognize the difficulties of such a task but liken it to the successful, collective effort of climate scientists over the past four decades to improve the predictive capabilities of climate forecasts.

As a passionate naturalist and philosopher, there is no doubt Humboldt would agree with Urban et al.’s conclusion that “ultimately, understanding how nature works will provide innumerable benefits for long-term sustainability and human well-being”. I encourage you to read the review article yourself if you’re interested in more details on Urban et al.’s views of a ‘practical way forward’ in the field of biodiversity forecasting. For a historical and perhaps more romantic account of the study of biodiversity, check out Andrea Wulf’s biography of Alexander von Humboldt, called The Invention of Nature.

 *This is an oversimplified example based off of a study on biodiversity and climate change in U.S. National parks (Burns et al. 2003)

References:

Burns, C. E., Johnston, K. M., & Schmitz, O. J. (2003). Global climate change and mammalian species diversity in US national parks. Proceedings of the National Academy of Sciences100(20), 11474-11477.

Urban, M. 14 September 2016. Carbon Brief. Guest post: How data is key to conserving wildlife in a challenging environment. From: https://www.carbonbrief.org/guest-post-data-key-conserving-wildlife-changing-climate (Accessed: 22 September 2016)

Urban, M. C., Bocedi, G., Hendry, A. P., Mihoub, J. B., Pe’er, G., Singer, A., … & Gonzalez, A. (2016). Improving the forecast for biodiversity under climate change. Science353(6304), aad8466.

Wulf, A. (2015). The Invention of Nature: Alexander Von Humboldt’s New World. Knopf Publishing Group.