By Neyssa Hays
The South Yamhill and Yamhill Rivers combined run through 71 miles of Northwest Oregon farmland and small towns, including Sheridan, McMinnville, Dundee, and Dayton (from west to east). A tributary of the Willamette River, the bi-river system has become an important spawning ground for the threatened and evolutionarily significant unit (ESU) of Oregon Coastal Coho Salmon (Oncorhynchus kisutch) as well as a winter refuge for Chinook Salmon (O. tshawytscha) smolts and juveniles, and the historic grassland prairies surrounding the lower sections were home to the endangered Fender’s Blue Butterfly (Icaricia icarioides fenderi) as well as other enlisted species (Good et al. 2005, McIntire et al. 2007, Togstad 2011).
Creating the Yamhill Rivers Reserve, a nature reserve that stretches the length of the South Yamhill and Yamhill River system at a width of at least 300 feet on each side of the river, would form a riparian zone of 5370 acres of contiguously protected habitat with minimal loss of agricultural land for any one farmer or business. In addition, adding a parcel of roughly 700 acres along the river that includes a small wetland area would provide land that could be restored to oak savannah and grassland prairie habitat.
The source of the South Yamhill River is located at coordinates 45.110556, -123.727778, in the foothills on the east side of the Coast Range, at an elevation of roughly 551 feet (Google maps 2012). The river then flows east. By the time it joins with the North Yamhill River to become the Yamhill River, it has dropped to an elevation of 75 feet; the Yamhill River continues the descent to 59 feet at its confluence with the Willamette River. The Yamhill Basin watershed varies in elevation from a high of over 3400 feet at the peak of Trask Mountain to a low of roughly 59 feet at the confluence of the Yamhill River and the Willamette River (Bash & Ishii, eds. 2002). The watershed, including the Yamhill River system, was carved into rolling hills and an expansive flatland by the Missoula Floods, which also deposited granite, quartzite, and slate. The river floodplains are composed predominantly of deep alluvial deposits of sand, gravel and silt over sedimentary rock. Average annual rainfall is 50 inches or less, most of which falls between November and March; temperatures are mild with mean winter temperatures in the low 40’s (F) and high summer temperatures averaging in the low 80’s (F).
Over the last twenty years, the population of Yamhill County has experienced a higher growth rate compared to the rest of the state and is predicted to grow from 101,000 to nearly 156,000 people over the next thirty years, with the highest concentrations in the towns near the South Yamhill River (Bash & Ishii, eds. 2002). As populations grow, pressure to subdivide and build on the land along the river will increase. Most of the land surrounding the Yamhill River system is currently farmed, and while some farmers allow a wide margin between plowed land and the river, many farmers work the land within a few feet of the embankment, a practice that leads to high soil erosion, muddied rivers, warm water temperatures, and higher run-off of farm chemicals (fertilizer, pesticides, and herbicides). Creating a wide, protected riparian zone would buffer the rivers from these effects and will ensure a healthier ecosystem for future generations.
In addition to safeguarding habitat for Coho Salmon and Fender’s Blue Butterflies, the Yamhill Rivers Reserve would protect several other species, including plants, insects, birds,amphibians, mammals, and other fish (some threatened or endangered, others of concern; USFWS 2012). Threatened and endangered plant species that would potentially benefit from this reserve are Water Howelia (Howelia aquatilis), Willamette Daisy (Erigeron decumbens var. decumbens), Kincaid’s Lupine (Lupinus sulphureus ssp. kincaidii), and Nelson’s checkermallow (Sidalcea nelsoniana; CPC 2010). The last two plants are important food sources for the Fender’s Blue Butterfly. Other species of concern that may benefit from the reserve include the Streaked Horned Lark (Eremophila alpestris strigata), the Southern Torrent Salamander (Rhyacotriton variegates), the Long-eared Myotis Bat (Myotis evotis), Coastal Cutthroat Trout (Oncorhynchus clarki ssp) to name a few.
The most obvious landscape features of interest for the Yamhill Rivers Reserve are the rivers themselves. Historically, the rivers wound through habitats such as mixed conifer-deciduous foothills and oak savanna (Bash and Ishii, eds. 2002). The latter of the two is perhaps the least obvious landscape feature of interest considered in this plan, though of high significance. Oak savanna and associated grassland prairie were once abundant habitats throughout much of North America and provide important food sources and refuge for a variety of organisms, including Fender’s Blue Butterfly, Streaked Horned Lark, Pygmy Rabbits, game birds, deer, and many others. Because the land on which they grow is prized for agriculture, today less than 0.5% of natural prairies and oak savanna remain and much of that has been severely affected by invasive species (McIntire et al. 2007).
In 1996, the Oregon State University Extension Service surveyed Yamhill County residents and found that over 90% of respondents supported continuing strategic planning for water quality and watershed management (Bash and Ishii, eds. 2002). The South Yamhill River is listed under section 303 of the Federal Clean Water Act with concern over water quality issues including “[high] temperature, flow modification, and bacteria,” all having harmful effects to many stream organisms, including salmon. Riparian zones counter all of these negative effects, and the longer and wider the continuous zone is the more effective it becomes. Cool water temperatures are of utmost importance throughout the salmon life history and deep riparian zones with tall trees are ideal for shading and cooling rivers and streams. Recent studies in Ireland have shown that a mix of dense canopy and sporadically open areas create conditions beneficial to macroinvertebrates that are important food sources for salmon (McCormick and Harrison 2011); this condition can be created in the initial stages of the reserve through the planting of fast-growing, large native riparian species such as alder, willow, and cottonwood as well as smaller shrubs such as elderberry and spirea. As riparian zones age, debris from falling trees and other plants serve to modify the water flow and offer refuge to fish and other animals. The root systems of the plants and soil of riparian zones act as natural filter systems against bacteria and chemical pollutants.
In addition to maximizing the filtering system described above, the 300-foot width of the Yamhill Rivers Reserve is necessary to encourage species diversity. It is currently standard practice (and law in many countries and states in the US) in the timber industry to leave a riparian buffer when cutting timber; such buffer strips vary in width from an average of 50 feet to a high of 165 feet (Whitaker and Montevecchi 1999 and Lee et al. 2003). While studies have shown that these widths are ample to moderate edge effects on trees along riverbanks, response of bird populations varies with width of riparian zones (Whitaker and Montevecchi 1999 and Harper et al. 2007). Whitaker and Montevecchi (1999) found that in riparian buffer zones of any width populations of birds generally associated with river habitats resembled those of uncut river areas. Interior forest bird populations, however, increased somewhat with increasing width, and the scientists postulated that it was likely that wider riparian buffer zones would have a positive influence on these populations.
Similarly, studies of Fender’s Blue Butterflies have shown that populations respond positively to larger patches of habitat (McIntire et al. 2007). Studies over a ten-year period followed by model simulations indicate that increasing butterfly refuges to at least 340 acres of connected patches have the potential to increase populations from the current 5,000 individuals to upwards of 65,000. Prairie acreage of this size would also be beneficial to the Streaked Horned Lark, which has been shown to require open areas of over 300 acres to support a healthy nesting population (FWS 2011). The remaining ~350 acres of the 700 acres planned would be restored to oak savanna, which would serve a variety of native animals that have lost most of their habitat to farming during the last two centuries.
Trophic Level Considerations
Players in the trophic levels will depend to some respect on whether they are aquatic or terrestrial species, although there are certainly crosses as well. In the river, the top trophic level is most likely to be the salmon; with smaller fish and macroinvertebrates at the second level; and in the first level a combination of detritus (including salmon carcasses), higher level plants, and algae.
The Yamhill River system was previously “cleaned” of woody debris used by all trophic levels as habitat, food, or substrate; subsequent winter flooding washed away gravel imperative to spawning (Bash and Ishii, eds. 2002). Management actions will include planting of fast growing, tall species of trees as well as slower growing trees to provide shade and eventual deadwood for all trophic levels. It may be necessary to include woody debris in the initial restoration projects as well as laying down appropriate gravel.
Terrestrial primary producers along the riparian corridor will include black cottonwood, alder, willow, and understory plants such as elderberry and spirea in the initial stages, followed by such slow-growing species as big-leaf maple, bitter cherry, Douglas fir, and western red cedar. Some early producers and saplings of slow-growing species will require being planted while others will likely self-propagate once the land is no longer being cleared for farming. The oak savanna and grassland prairie will need to be extensively planted with native species and monitored for control of invasive species. Herbivores, the second trophic level, will include Pygmy Rabbits, Pocket Gophers, several species of birds, deer, and Fender’s Blue Butterflies; some of these species, such as deer, will arrive autonomously while the populations of others, such as Pygmy Rabbits and Fender’s Blues, will need to be transplanted after the plants are well established. Likely the top trophic level will be dominated by coyotes and foxes, but will also include birds such as osprey, hawks, eagles, and owls as well as minute predators such as Myotis Bats. It is not out of the question, however, that cougars would also use the riparian corridor, though this is likely to take several years.
Of greatest concern to stakeholders would be the loss of land used for farming, timber, or development. A square acre is 208 feet per side, and one mile is 5280 feet long; so for every mile of riparian zoning, a landowner would stand to lose roughly 38 acres on each side of the river. Additionally, much of the upper end of the river runs through land owned by the Confederated Tribes of Grand Ronde or its members. While they may be supportive of this plan, many of their tribal members are farmers and would be hard-pressed to give up their farmland for a nature reserve. In the bottomland of the river about five miles west of McMinnville, Riverbend Landfill operates right up to the edge of the river and in the last few years management expanded their operation, putting in a state-of-the-art waste disposal system.
Further down river, the South Yamhill flows directly through McMinnville and in several places the highway and other roads cross over. These areas cannot be protected or restored at present and it is not likely that they will be in the future either. However, local planners are already establishing urban growth boundaries (UGB’s), which could include riparian zoning (Bash and Ishii, eds. 2002). Throughout the watershed, water quality would benefit by replacing culverts with bridges.
The first management actions would be to make the proposal to the community and listen to the concerns of the primary stakeholders. Management would need to educate the stakeholders on the benefits of riparian buffering and healthy water systems, such as reduced flooding and bank erosion, and decreased need for fertilizing because the riparian zone would support more native pollinators. Perhaps there could be incentives for stakeholders to support the plan as well. Likely, the 700-acre parcel for oak savanna and grassland prairie would need to be purchased. All involved parties then would try to come to an agreement.
Once the area is established, subsequent management actions should be first to design and carry out initial water quality and wildlife studies. Once a baseline is established, management will engage in removal of invasive species, planting native species, and continued monitoring of the ecological health of the area. Additionally, stakeholders will be invited to regular informational meetings to discuss progress and concerns.
The 100-year predictions for Pacific salmon are dire, with most populations in the lower latitudes going extinct due to climate change. However, if river systems such as the Yamhill can be set-aside as salmon sanctuaries and the waters cooled enough, the salmon stand an increased chance of survival. Many of the tree species of older riparian corridors are long-lived species with varying growth rates. In 100 years a Douglas fir may have reached nearly its full 230 feet and stand another 800 years growing slowly in diameter, while the oaks in the savanna will have only reached half of their full 85 feet and may persist another 250 years. Several of the oaks in the savanna will have lost limbs and become hosts for cavity dwellers, including Wood Ducks, Acorn Woodpeckers, and bats. Along the river, Black Cottonwoods would likely out-compete the Red Alder and dominate the embankment. Logs and debris from fallen trees as well as water-loving willows will have created a complex river scene. McIntire et al. (2007) predicted populations of Fender’s Blues in a 300-acre system would stabilize after 25 years to between 50,000 and 65,000 individuals. Other populations of short-lived species such as songbirds, bats, and rodents will likely have reached their carrying capacity as well and will have settled into relatively stable populations. Longer-lived species such as deer and coyotes will likely still be increasing in population.
In 1000 years the area will have experienced some climax communities and some of the Douglas firs would be nurse logs for species such as Western Hemlock as well as under-story plants such as huckleberry, salal, and snowberry. Pileated woodpeckers will likely be heard searching for food and making homes in snags and diseased trees. The oak savanna as well will have seen replacements and successional changes. Historically oak savanna and grassland prairies were maintained through fire, both controlled and natural. It is conceivable that future management practices would also include controlled fire; this would have the desirable effects of removing many invasive species and ridding the area of tree-damaging fungus and disease.
Because Coho Salmon are not native to the Yamhill River system, it is possible that their increased presence would have a negative effect on other species in the river system. The Coho currently spawning in the Yamhill Rivers are naturally returning descendents of released fish from a far-off hatchery, a practice that was discontinued in 1997 after nearly fifty years (Togstad 2011). However, on a whole, wild Pacific salmon numbers are dwindling for many reasons, including climate change, over-fishing, and competition with hatchery-reared salmon; supporting populations that are now naturally spawning has the potential for preserving a species that is struggling in its historic rivers. Other impacts of the riparian zone include higher biodiversity, decreased run-off, and cleaner, cooler waters.
The Yamhill Rivers Reserve would improve water quality in the South Yamhill and Yamhill Rivers, and increase Coho salmon and Fender’s Blue butterfly populations for many future generations. Moreover, it could become a model for riparian management systems throughout the Pacific Northwest and beyond.
Bash, J. and J. Ishii, eds. 2002. Upper South Yamhill River watershed assessment. Oregon Watershed Enhancement Board 1-115. Accessed 4/25/2012 at: http://nrimp.dfw.state.or.us
CPC. 2010. Center for Plant Conservation Website. Accessed 4/20/2012 at: http://www.centerforplantconservation.org
FWS. 2011. Species Fact Sheet Streaked Horned Lark Eremophila alpestris strigata. Fish and Wildlife Services. Accessed 5/30/2012 at: http://www.fws.gov
Good, T.P., R.S. Waples, and P. Adams, eds. 2005. Updated status of federally listed ESUs of West Coast salmon and steelhead. U.S. Dept. Commer., NOAA Tech. Memo. NMFSNWFSC-66, 598 p.
Lee, P., C. Smyth, and S. Boutin. 2004. Quantitative review of riparian buffer width guidelines from Canada and the United States. Journal of Environmental Management 70:165-180.
McCormick, D. P. and S. S. C. Harrison, 2011. Direct and indirect effects of riparian canopy on juvenile Atlantic salmon, Salmo salar, and brown trout, Salmo trutta, in south-west Ireland. Fisheries Management and Ecology 18:444-455.
McIntire, E. J. B., C. B. Shultz, and E. E. Crone. 2007. Designing a network for butterfly habitat restoration: where individuals, populations and landscapes interact. Journal of Applied Ecology 44:725-736.
Togsad, J. 2011. Simple way to save salmon: Conservation District helps landowners improve conditions for fish in local streams. The News Register May 21, 2011. Accessed 5/30/2012 at: http://www.newsregister.com
USFWS. 2012. Federally listed, proposed, candidate species and species of concern under the jurisdiction of the Fish and Wildlife Service which may occur within Yamhill County, Oregon. Accessed 4/18/2012 at: http://www.fws.gov/oregonfwo/Species/Lists/Documents/County/YAMHILL%20COUNTY.pdf
Wondzell, S. M., M. A. Hemstrom, and P. A. Bisson. 2007. Simulating riparian vegetation and aquatic habitat dynamics in response to natural and anthropogenic disturbance regimes in the Upper Grande Ronde River, Oregon, USA. Landscape and Urban Planning 80:249-267.
Whitaker, D. M. and W. A. Montevecchi. 1999. Breeding bird assemblages inhabiting riparian buffer strips in Newfoundland, Canada. Journal of Wildlife Management 63:167-179.
By Neyssa Hays
As scientists learn more and more about certain species, it is becoming clearer that some are important for ecological structure and some species are good indicators of the health or illness of the area in which they live. Sea otters are both and taking steps to protect them may be taking steps to protect us all.
Sea Otters as Keystone Species
The largest member of the family Mustelidae (minks, weasels, badgers, etc.), the charismatic sea otter (Enhydra lutris) is a well-documented keystone species because of their preferred food source: the spiny, purple sea urchin (Estes et al. 1982) A keystone species is a species that has a disproportionately large effect on its environment in comparison to its abundance. Left unchecked, herbivorous urchins decimate kelp forests, leaving vast areas of ocean desert where once stood lush forests teeming with life (Estes et al. 1982 and 2010). “Without any [other] natural predators,” wrote sea otter biologist James Estes, “urchins can become so numerous that they overgraze the lush kelp forests that otherwise abound along the West Coast. When this happens, the lost ecological benefits — both to society and the environment — are dramatic” (Estes 2012). Used by a plethora of ocean dwellers (including economically important species) for food, shelter, and rearing ground, the kelp forests are also critically central in maintaining coastline integrity and mitigating erosion (Estes et al. 2010).
Sea otters as Sentinel Species
sea otter illnesses alert human welfare officials to potentially dangerous conditions along the coastline (Jessup et al. 2004). If the waters in which they live are healthy, sea otters are as well, but with rising pollutants in coastal waters, protecting otter health has become increasingly difficult. Fertilizer and pesticide runoff from lawns and farms; petroleum slicks from driveways, parking lots, gas stations, and tanker accidents; and diseases from domesticated animals are all taking their toll on the health of our oceans, and sea otter populations are showing the effects. While birth rates have remained normal, mortality of adults is high and much of that has been from disease caused by contact with anthropogenic (of human origin) waste (Miller 2012), especially along coastlines with high human populations. This is particularly problematic for females who remain close to the waters in which they were born and are therefore exposed to the same contaminants through their entire lives (Jessup et al. 2004).
“All the research we have done to date suggests that there’s no one single mortality factor but that the deaths are caused by a suite of interacting stressors,” states Tim Tinker of the U.S. Geological Survey’s otter research program (Kettmann 2010).
Water pollution is hazardous to sea otters because of their life history patterns and habits, and each pollutant poses a distinct problem. Because sea otters dive to hunt for and eat predominantly bottom-feeders (such as clams, crabs, sea urchin, and abalone) but spend most of their time floating on the surface, they come in direct contact with anything that is washed out to sea, including toxins and parasites from anthropogenic sources (Miller 2012). On the surface of the water where they spend most of their time, sea otters are exposed to oil slicks and toxic algal blooms, problems that have increased dramatically in recent years, while diving for their food requires swimming through other suspended pollutants.
Sea otters are born in and spend nearly their entire lives in the water, and though they are considered semi-aquatic by biologists because they are lacking features of fully aquatic mammals such as cetaceans (whales and dolphins) (Yeates 2007), their hind limbs are so well adapted for swimming, they are nearly useless on land (Kenyon 1969). Unlike other sea mammals, sea otters do not have insulative blubber but instead maintain thick pelage (fur) and a very high metabolism to ward off hypothermia (Yeates 2007). If covered in petroleum, the otters’ thick fur loses its insulating properties and the animal soon freezes to death (Love 1992, Jessup et al. 2004, and Miller 2012). Their high metabolism requires that sea otters consume prey at a rate of 25-35% of their own body weight each day; when the food the sea otters eat is contaminated, the contaminants become concentrated within the sea otters’ bodies, often to deadly levels (Jessup et al. 2004). Because sea otters eat many of the same shellfish that humans do, their illnesses are potential indicators of problems in one of our own food sources.
In recent years, deceased and ill otters have shown high levels of the parasites Toxoplasma gondii, found in the feces of cats (Felis catus), and Sarcocystis neurona, from opossum (Didelphis virginiana) feces (The Otter Project 2011, Righthand 2011, and Miller 2012). Both cats and opossums were introduced to the Pacific coastal area by humans who brought them here as pets in the late 1800’s and early 1900’s, and have since become invasive (Maser 1998). Scientists suspect that the fecal parasites, both related to malaria (Miller 2012), are washed out to the oceans through storm drains and, in the case of cats, through the sewage system when people dispose of cat litter in the toilet.
Sea Otters and Human History
Sustainably hunted for millennia by indigenous people of the Pacific Crest, when in 1741 Russia’s Vitus Bering and his crew first saw sea otters, the marine mammal’s populations were such that German naturalist Georg Wilhelm Steller stated, “They covered the shore in great droves” (Love 1992). Like many other animals on the Endangered Species List, sea otters were then driven to near extinction in California as early as 1841 and elsewhere in their range by 1911 because of their economic importance to humans (Love 1992). Early explorers from Russia, Spain, England, France and the newly formed U.S. found great wealth to be made from the sales of the thickly furred hides that act as sea otters’ only insulation against the frigid waters of their natural habitat. Though sea otters are now legally protected from hunting and human encroachment in many areas, the protection of sea otters is still a contentious issue (Barlow 2012 and Estes 2012).
After they were listed as “threatened” in 1977, Southern sea otters (those living in the waters off the coast of California) were afforded protections. U.S. Fish and Wildlife established sea otter reserves on San Nicolas Island, which they share with the U.S. Navy, and “no otter zones,” shellfish harvest areas from which “stray” otters can be captured and returned to their reserves (Kettmann 2010). This theoretically keeps them from competing with human shellfish harvesters. Recently the San Nicolas Island reserve area was challenged when Rep. Elton Gallegly introduced a bill to protect the Navy’s shooting rights on the island (Barlow 2012). Neither environmental groups nor fishermen have ever been pleased with the “no otter zones;” environmental groups say the protections don’t go far enough while the fishermen rightly point out that the sea otters ignore the zoning laws (Kettmann 2010). Similarly, in Puget Sound and the waters off Alaska, British Columbia, and Washington, where sea otter populations are generally healthy, state, province, and tribal fisheries managers struggle with balancing the welfare of the semi-aquatic mammals against that of the human fishing communities (Laidre and Jameson 2006).
Why We Should Care
Planetary ecology is like a lace cloth, delicate, intricate, and complex. Neither scientists nor politicians, nor the public, nor corporate leaders can completely predict what will happen if one or another species is protected or not. But often times, as is the case with sea otters, protecting them starts a chain reaction of protection for other creatures, including ourselves. As a sentinel species, sea otters’ well being is indicative of the health of the water in which they live, the same waters in which we play and fish. If not out of compassion for the wellbeing of other creatures, that healthier otters = healthier water = healthier humans should be enough of a reason to care about this small mammal of the North Pacific.
What We Can All Do to Help
Here’s the great news: there are many very easy things each of us can do to help improve the health of the oceans’ creatures, which in turn will help the health of every living thing on the planet, including our own.
1) Limit the amount of petroleum-based products you use by
a) Walking or riding your bike to run errands; when commuting, take mass transit or ride your bike
b) Use plant-based detergents, soaps, lotions and personal grooming products
c) Reduce plastic in your life by using reusable grocery bags and glass food storage containers (such as peanut butter or jam jars)
d) Purchase local, sustainably produced food
2) Keep chemicals out of storm drains by practicing organic gardening techniques and making sure your car or other gas-powered machines don’t leak oil or other fluids.
3) Bag your cat’s waste and used cat litter and send it out with your garbage; do not flush cat feces down the toilet.
4) Cut up the rings from beverage six-packs before throwing them away.
For more ideas on what you can do to help, visit The Otter Project at http://otterproject.wordpress.com.
Barlow, Z. (2012, February 16). Proposed bill addresses sea otter controversy. Ventura county star. Retrieved from http://m.vcstar.com
Estes, J. A., M. T. Tinker, J. L. Bodkin. 2010. Using Ecological Function to Develop Recovery Criteria for Depleted Species: Sea Otters and Kelp Forests in the Aleutian Archipelago. Conservation Biology 24:852-861.
Estes, J. A., R. J. Jameson, E. B. Rhode. 1982. Activity and Prey Election in the Sea Otter: Influence of Population Status on Community Structure. The American Naturalist 120: 242-258.
Estes, J.A. (2012, February 21). On Sea Otters, we need to see the big picture. LA Times. Retrieved from http://www.latimes.com.
Jessup, D., M. Miller, J. Ames, M. Harris, C.. Kreuder, P. Conrad, J. Mazetz. 2004. Southern sea otter as a sentinel of marine ecosystem health. EcoHealth 1:239-2004.
Kenyon, K. W. 1969. The sea otter in the eastern Pacific Ocean. Bureau of Sport Fisheries and Wildlife. Washington, D.C.
Kettmann, M. (2010, September 25). The mystery of the vanishing California sea otters. Time. Retrieved from http://www.time.com.
Laidre, K. L. and Jameson, R. J. 2006. Foraging patterns and prey selection in an increasing and expanding sea otter population. Journal of Mammalogy 87:799-807.
Love, J. A. 1992. Sea otters. Golden, Colorado: Fulcrum Publishers.
Maser, C. 1998. Mammals of the Pacific Northwest: from the coast to the high Cascades. Corvallis, Oregon: Oregon State University Press.
Miller, M. 2012. Sick Sea Otters and Potential Health Risks for Humans at the Land-Sea Interface. Abstract from presentation at the AAAS Annual Meeting, Feb. 18, 2012 in Vancouver, B.C.
Righthand, J. (2011, September). Otters: The Picky Eaters of the Pacific. Smithsonian magazine. Retrieved from: http://www.smithsonianmag.com.
The Otter Project 2010. “Sea otters where are you?” Sea Otter Scoop: The Official Blog of the Otter Project. Accessed 2/18/2012 at: http://otterproject.wordpress.com
Yeates, L. C., T. M. Williams, T. L. Fink. 2007. Diving and foraging energetics of the smallest marine mammal, the sea otter (Enhydra lutris). Journal of Experimental Biology 210:1960-1970.
Armstrong, M. (2004, December 30). High tide strands sick sea otter. Homer News. Retrieved from: http://homernews.com
France, L. 2007. Sea otters. Retrieved from: http://courses.washington.edu/mareco07/students/lindsay/Sea%20Otters.html
USGS, undated. Sea otter range map. Retrieved 3/8/2012 from: http://www.werc.usgs.gov/ProjectSubWebPage.aspx?SubWebPageID=1&ProjectID=91
By Neyssa Hays
Salmon conservation and management are complicated issues, in which the international hatchery system plays a significant, if not always beneficial, role. This paper is a brief examination of salmon hatcheries, especially those of the Northern Pacific in general and the Pacific Northwest more specifically; their effects on wild salmon populations; attempts to mitigate those effects; and potential guiding principals, public policy, or international agreements that could be used to guide interstate and international discussions on collaborative efforts.
The management of salmon (Oncorynchus spp. and Salmo salar) as both free organisms and a natural resource is a complex and often contentious issue with no clear answers. No one questions the value of salmon, per se; around the world salmon are prized for many tangible and intangible reasons including, but certainly not limited to, their importance as a keystone species, jobs, nourishment, beauty, and symbolism. However, as Lackey (2013) documents, though public polls show people value and support “saving the salmon,” there are so many other issues with which we must contend that conservation measures are often set aside for a later time.
However, in combination with their anthropologic significance and as a result of their life history pattern, salmon are at the center of a great debate that has been raging for nearly 150 years: how can we have both healthy nature and mass industry? Salmon move through and live in or near environments most heavily used by humans throughout their lives, and as the forests, rivers, estuaries, and oceans on which the salmon depend degrade, pressures on salmon populations are steadily increasing, placing many salmon species on the Endangered and Threatened Species List. There are many reasons for the salmon’s initial decline and subsequently depressed populations and there have been many attempts at reparation. The salmon hatchery system (from here out called “hatcheries”) has been both an attempt to repair the populations and an exacerbating part of the decline.
Because of the deleterious effects in some areas hatchery managers and conservation non-government organizations (NGOs) are working on various management strategies to reduce the negative impacts hatcheries have on wild salmon (Holt et al. 2008; Kaeriyama et al. 2011; Kostow 2012). Additionally, due to the international nature of ocean-going organisms, including salmon, there exists a need for cooperation and collaboration between international governing bodies to reduce the impacts in the ocean of hatchery salmon (Zaporozhets and Zaporozhets 2004; Holt et al. 2008; Kaeriyama et al. 2011; Kostow 2012; Rand et al. 2012). Unfortunately, there currently exists no multi-national organization, governing body, or clear doctrine encouraging such collaboration (Holt et al. 2008; Rand et al. 2012). However, there are several domestic and international agreements that when put together could be used for the creation of guiding principles and governing bodies.
Definition of Terms
The terms “wild,” “hatchery,” and “natural,” can mean different things depending on the context of their use. For instance, in the grocery stores, the term “wild salmon” indicates the fish was caught in a net in the “wild” (usually open ocean), as opposed to having been raised completely in captivity, regardless of where or in what conditions it was born. For the purposes of this paper, however, the terms are defined thus: a “wild fish” is one that was spawned in a natural stream or river from lineage of fish also spawned in a natural stream or river; unless otherwise noted, a “hatchery fish” is a fish that was spawned using artificial methods in a hatchery setting; “natural spawning” is spawning in a stream or riverbed without the aid of humans, regardless of whether the fish is of wild or hatchery heritage; finally, “artificial spawning” is a human-dominated process in which female salmon are stripped of their eggs, males are “milked” for their milt, the eggs and milt are mixed together, and placed in special incubators.
Effects of Hatchery Salmon on Wild Salmon
With the vast and growing scientific evidence about hatchery effects on wild salmon, there is very little argument that hatchery fish have an overall detrimental impact on wild fish (Lichatowitch 1999; Zaporozhets and Zaporozhets 2004; Holt et al. 2008; Kaeriyama et al. 2011; Grant 2012; Kostow 2012; Katz et al. 2013; Lackey 2013). Among these effects, Kostow (2012) lists the most commonly documented as hatchery fish predation of wild fish; competition for resources; predator attraction; disease transmission; and “density dependent effects triggered by large numbers of hatchery fish in freshwater and marine environments.”
At the extreme end, in both Russia and the United States, researchers have documented entire wild populations of a river system going extinct within twenty years of a large hatchery being opened (Zaporozhets and Zaporozhets 2004; Kostow 2012). Clearly this goes against conservation of the species. Highlighting five different management plans currently in effect in various places in Oregon to reduce these impacts and hopefully increase wild salmon populations, Kostow (2012) notes that the different strategies are having mixed results, but are generally positive.
Recently, researchers and conservation NGOs have become increasingly concerned about the effects hatchery salmon are having on wild salmon and the rest of the ecology in the open oceans. Preliminary studies indicate that there is strong resource and spatial competition in the oceans, which is expected to worsen as the effects of ocean acidification, pollution, and resource extraction take their course and resources diminish (Zaporozhets and Zaporozhets 2004; Sabine 2011; Daly 2012; Kostow 2012). Though studies show that one-on-one, wild salmon dominate hatchery salmon when competing for resources, hatchery salmon in the open ocean can easily overwhelm wild salmon simply by outnumbering them (Zaporozhets and Zaporozhets 2004; Daly et al. 2012; Metcalf et al. 2013). During poor ocean-condition years, this effect is magnified, especially when hatcheries release smolts based on factors other than available resources (Daly et al. 2012).
Global Considerations for Hatchery Management
Because of the international nature of managing the open oceans combined with the salmon’s anadromous life history, the question of hatchery management is evolving from a domestic discussion to one of international concern (Zaporozhets and Zaporozhets 2004; Holt et al. 2008; Kaeriyama et al. 2011; Rand et al. 2012). Every U.S. state and nation state of the Northern Pacific and Northern Atlantic has an extensive salmon hatchery system (SOS 2013). In the open ocean salmon do not differentiate based on nation of origin; they compete with each other indiscriminately. Therefore, there is a growing interest in balancing releases from hatcheries of the entire Northern hemisphere. However, as Holt et al. (2008) discuss, due to issues related to food security, domestic and international economics, and sovereignty, there is great potential for political tension to thwart international efforts at restructuring the hatchery system. Recent court actions regarding catch support their analysis.
In Salmon Spawning & Recovery Alliance v. Gutierrez (2008), for example, plaintiffs claimed that the 1999 Amendment to the Pacific Salmon Treaty Act of 1985 (PST 1985) allowed Canadian fisheries to harvest unreasonable rates of Environmental Species Act (ESA) protected salmonids and the U.S. government should not, therefore, renew the treaty. The court disagreed, noting that the PST 1985 was executed by an international organization, the Pacific Salmon Commission (PSC), consisting of sixteen delegates from both Canada and the U.S. (PSC 2006), who set the catch limits for both countries annually “based on pre- and in-season estimates of abundance” (Salmon Spawning & Recovery Alliance v. Gutierrez (NOAA) 2008). While this case is about creating international catch agreements, not restricting hatcheries, it underlines the difficulties of managing straddling fish populations.
Furthermore, as discussed by Rand et al. (2012), while there is an abundance of information about wild-hatchery interactions for the Columbia River, there is very little information about the issue in other regions, especially in the Western Pacific. Until it is remedied, this lack of information described will only serve to exacerbate political tensions surrounding any attempts at international policy towards restricting hatchery output. Additionally, in the U.S. there is still a pressing question that needs to be settled before serious hatchery reform can take place: are hatchery- and wild-spawned salmon significantly different fish?
Historically, both the courts and the National Marine Fisheries Service (NMFS) have wavered back and forth on the question of including hatchery salmon in total salmon counts when making management decisions such as whether or not a species is to be afforded protection under the Endangered Species Act (ESA) (Kostow 2012). As an example, in Oregon Natural Resources Council v. Daley (NMFS) (1998), Magistrate Judge Janice M. Stewart determined that NMFS was erroneous in including hatchery counts to determine that the Evolutionarily Significant Unit (ESU) of Oregon Coast coho salmon was not threatened per the Endangered Species Act. Judge Stewart concluded that NMFS’s decision to not list the Oregon Coast coho salmon ESU was unlawful, went against its own code, and “placed the risk of failure squarely on the species.”
Three years later, in Alsea Valley Alliance v. Evans (NMFS) (2001), U.S. District Court Judge Michael Hogan reversed the court’s position regarding this ESU of coho salmon. Judge Hogan stated that by not including hatchery salmon in the counts when listing the coho ESU, NMFS was going against Congress’ limitation on “the Secretary’s ability to make listing distinctions among species below that of subspecies or a DPS [distinct population segment] of a species.” Then in Alsea Valley Alliance v. Lautenbacher (2007) U.S. District Court Judge Michael Hogan ruled that the NMFS are within their rights to list hatchery- and wild-spawned fish separately. Finally, in Trout Unlimited v. Lohn (2009) the 9th Circuit Court decided that for ESA listing purposes, hatchery- and wild-spawned fish are not necessarily different. However, the court also noted that NMFS has legal authority when it comes to separating them out as necessary.
Currently for Oregon waters, Federal district courts hold that wild and hatchery salmon are not to be counted together (National Wildlife Federation v. National Marine Fisheries Service 2011). In his opinion on the case, U.S. District Court Judge James Redden cited his previous finding that NOAA Fisheries’ decision to count hatchery-spawned salmon with naturally spawning fish when deciding whether or not to afford ESA protection a “biological opinion [that was] arbitrary and capricious.” He also wrote that since the “Federal Defendant’s [have a] history of abruptly changing course, abandoning previous BiOps, and failing to follow through with their commitments,” the courts would keep control themselves. However, Judge Redden has since stepped down (Learn 2011). Additionally, in making ESA listing decisions, the U.S. Fish and Wildlife Service (USFWS) counts hatchery salmon with wild salmon for some ESUs throughout their range (USFWS 2013).
Because of the government and court’s tendency to waiver on the issue of classification, there will need to be a definitive answer from the scientific arena if we are to make clear strides in protecting wild salmon. To do this, the wild-spawned and hatchery-spawned salmon will likely have to be deemed separate subspecies or at least distinct population segments of the species (Alsea Valley Alliance v. Evans (NMFS) 2001). This would be difficult, since the definition of a species includes lack of naturally occurring crossbreeding and stray hatchery fish do breed naturally with wild fish (Bowlby & Gibson 2011; Christie et al. 2012; Kostow 2012; Rand et al. 2012). However, studies have shown quantifiable genetic differences between wild- and hatchery-spawned salmon (Fritts et al. 2007; Christie et al. 2011). Additionally, there is much evidence showing that stray hatchery-salmon who mate with wild-spawned salmon produce young that are less fit than naturally-spawned young of wild- to wild-lineage (Fritts et al. 2007; Theriault et al. 2011; Zhivotovsky et al. 2011). Perhaps this is evidence that they are not successfully crossbreeding and are, therefore, separate subspecies.
Policy Support for Limiting Hatcheries
If the U.S. government decides in favor of wild salmon, defining them as their own subspecies, then they will clearly receive the protections of the ESA in nearly every river of the Pacific Northwest and California as well as in the oceans. Additionally, there is potential for supportive litigation for limiting hatcheries in the numbers of smolt they release and where the hatcheries can be located. Limiting smolt releases could be supported both domestically and internationally based on such agreements as the “Clean Water Act,” UNCLOS, and court cases that have blocked hatchery construction. Existing international committees could either grow to include management and regulation of hatcheries or be used as a template for creating new international committees.
In the Federal Water Pollution Control Act (2002) (commonly known as the “Clean Water Act”), Article 502(6) includes “biological materials” in the definition of “pollutant.” If hatchery salmon are a distinct population segment from wild salmon, it could be argued that hatchery salmon are “biological materials” that are doing harm to endangered species. Additionally, it is not unheard of to treat living organisms as pollution; Congress set the precedent in creating the National Invasive Species Act of 1996 (Invasive Species Act; Courtney et al. 2008). Applied hand-in-hand with the Clean Water Act, the Invasive Species Act is implemented by the Coast Guard to control marine organisms in ballast water of ocean-going vessels. These acts are limited in use in that they are domestic acts only and are not binding on any state other than the United States.
Similarly, the OSPAR Convention, which is signed by fifteen countries of Western Europe, is applicable only to the Northeast Atlantic, making it useful in Atlantic salmon conservation but less so in the Pacific region (OSPAR 2013). However, the second agreement of the OSPAR Convention, the Paris Convention for the Prevention of Marine Pollution from Land-based Sources of 1974 defines water pollution as anything introduced to the water by people that is harmful “to living resources and to marine ecosystems” (Raval 2013). Updates to the convention agreed upon in 1992 include the mandate that each governing state “strictly subject to … regulation … discharges to the maritime area, and releases into water or air which reach and may affect the maritime area” (OSPAR 2013). Clearly, hatchery salmon are released into the water by humans, reach and affect the oceans, and have been shown to be harmful to living resources.
Between the United States and Canada, Section 9 of the Pacific Salmon Treaty Act of 1985 states that in making salmon management decisions, the Pacific Salmon Commission shall “take into account the best scientific information available [that] result in measures necessary and appropriate for the conservation, management, utilization and development of the Pacific salmon resource” (PST 1985). While this treaty is concerned with harvest, it sets a precedent for making collaborative international management decisions with regards to salmon.
The United Nations Convention for the Law of the Sea (UNCLOS) allows the broadest application of international law. While the United States has not yet ratified the treaty, U.S. courts acknowledge that it is customary international law and utilize it when making case decisions (Van Dyke 2008). The Precautionary Principle (1995) places conservation as the foundation of fisheries management and requires states to “avoid activities that present uncertain risks to the marine ecosystem” (Van Dyke 2008). In addition, it calls for considering an ecosystem’s carrying capacity in management decisions. Further, Principle 15 of the Rio Declaration, which is held as the defining document of precautionary management states:
“In order to protect the environment, the precautionary approach shall be widely applied by States according to their capabilities. Where there are threats of serious or irreversible damage, lack of full scientific certainty shall not be used as a reason for postponing cost-effective measures to prevent environmental degradation” (Schiffman 2008).
In the United States, previous court cases set precedent for limiting installation of hatcheries. For example, in Wilderness Society v. US Fish & Wildlife Service (2003) the 9th Circuit Court ruled that USFWS could not put in a hatchery in a wildlife refuge because of potential harmful effects on wildlife, including wild salmon.
As stated by Holt et al. (2008), “there is currently no international governance structure with authority to unilaterally impose” international restrictions on hatchery production. However, there are international bodies that could expand their scope and jurisdiction or could be used as a template. In addition to North Pacific Anadromous Fish Commission (NPAFC) touted by Holt et al. (2008) as a potential organization whose mandates could be reconfigured, the Pacific Salmon Commission (PSC) could be refitted, expanded, or used as a template. The PSC is currently a governing body between the United States and Canada charged with overseeing the Pacific Salmon Treaty of 1985 (PSC 2013). While the PSC is currently only concerned with setting catch limits, it could be expanded to agreements on setting hatchery limits as well. Potentially, it could also grow to include commissioners from Russia and Japan. Alternatively and additionally, it could be used as a template for creating a new international commission for the Northern Pacific as well as an international commission for the Northern Atlantic.
If it is decided that there is no significant difference between hatchery and wild salmon, then the outlook for wild salmon is grim. We have put ourselves in a circular situation: the more hatcheries we build and smolts are released, the more they compete with wild-spawned fish, compounding the other stressors that are resulting in ever-lower counts of wild salmon, and the more we feel we need to build hatcheries and release more smolts to keep the total salmon numbers up. Perhaps it seems counterintuitive that in order to reap more benefits from the hatchery system we should limit what is sewn, but studies have shown that decreasing hatchery output has the potential for healthier smolts, juveniles with greater dominance and survival rates, and increased body size in returning adults (Brockman & Johnson 2010; Daly et al. 2010; Kostow 2012).
There is very little argument that hatchery salmon have a detrimental impact on wild salmon. However, the question of what is to be done about it raises a plethora of more complicated questions. How do we place limits on hatcheries when ostensibly they are breeding a failing natural resource? And, how do we accomplish this limit on an international level? With consideration for the previous questions the author makes the following recommendations: 1) Continue research on the question of wild and hatchery salmon as distinct population segments; 2) Keep wild and hatchery salmon populations separate to protect wild salmon genetics; 3) Continue with research to improve hatchery management practices; 4) Reduce hatchery output over time; 5) Train new fisheries biologists and managers to focus on holistic ecosystem management; 6) Recognize limits and changes in ocean and river carrying capacity; 7) Increase international discussion and information exchange on wild and hatchery salmon management practices and findings; 8) Utilize existing international commissions and treaties to impose restrictions on hatchery output; and 9) Increase public awareness and understanding of the issues facing wild salmon and the importance of salmon to the ecosystem.
The Precautionary Principle mandates that in the face of looming extinction, governing bodies not wait for scientific answers or consider economic outcomes before taking action to prevent the extinction. In many rivers, wild salmon are facing looming extinction. It is time to take action.
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