salmon

Modeling Fish on the Move

By: Marguerite Huber

How many places have you lived? Why did you move? Personally, I have lived in eight different places because of school and jobs. Other people move to find better opportunities, like housing or a place to raise their children.

Fish are sometimes forced to move as well. But, unlike you and I, fish cannot just get up and move across towns, states, and countries. They have to move across their own river networks to maximize survival.

For fish, the availability of sufficient spawning and rearing habitats can strongly influence the productivity of an entire river network. Fish also move based on certain environmental drivers like warming temperatures, and human activities such as land development, building of dams, and changes in stream channels, which can contribute to water pollution or alter fish habitat. Additionally, fish are affected by their interactions with other species. When different species interact, they can compete for resources or have a predator-prey relationship.

The Willamette river network, color-coded to show which of the 3 primary environmental conditions are currently most limiting habitat suitability for Chinook salmon, a species of high management concern.

The Willamette river network, color-coded to show which of the 3 primary environmental conditions are currently most limiting habitat suitability for Chinook salmon, a species of high management concern.

To fully understand fish in their changing environment, EPA researchers created a model that simulates groups of fish in river landscapes. This model helps determine how fish populations reproduce, move, and survive in response to both environmental drivers and species interactions. It is designed to help EPA assess the impacts of land development on fish assemblages, and better understand how these impacts may be intensified by climate change.

The researchers studied how Chinook salmon (Oncorhynchus tshawytscha) respond to steepness of the stream channel, flow, and temperature in the Willamette River basin of Oregon. This region is important to study because it is expected to experience substantial rises in human population and water demand over the next 50 years. The model, which can be applied to any watershed, helped create a map of the salmon’s abundance and distribution in the Willamette River basin. To capture species interaction, scientists also modeled the abundance of another fish, the northern pikeminnow (Ptychocheilus oregonensis), a native predator and competitor of Chinook salmon.

Afterwards, researchers modeled both species together, accounting for projected effects of competition and predation. They found that species interactions and temperature affect both Chinook salmon and northern pikeminnow. The results show species distributions throughout the basin and their projected responses to future stressors such as climate change, water consumption, and hydropower management.

Not only will EPA’s model help construct a map of fish on the move, but it will help inform the science used to develop water quality regulations and trading, help prioritize restoration, and advise management decisions.

About the Author: Marguerite Huber is a Student Contractor with EPA’s Science Communications Team

Editor's Note: The opinions expressed here are those of the author. They do not reflect EPA policy, endorsement, or action.

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Salmon Recycling: Waste Not, Want Not

EPA scientific diver and frequent “It All Starts with Science” contributor Sean Sheldrake recently shared some of his work on the Smithsonian’s Ocean Portal blog. The following was originally posted there.

By: Sean Sheldrake

Underwater pipe discharges fish waste.

Pipe discharges fish waste from processing factories. Photo byBruce Duncan, EPA

As a research diver for the US Environmental Protection Agency (EPA), one of my jobs is to make sure that people and companies working in the fish industry don’t dump too much waste in the ocean. On my first dive at an underwater waste site, my old salt of a dive partner hinted, “you might see a shark… or three” with a wink. “Okay,” I thought, “I can deal with a couple of sharks.”

Descending to the dump site, I soon saw circling dogfish and salmon sharks extending all the way from 80 feet to the surface—maybe 50 sharks, perhaps more. All those dogfish were drawn to a pile of Alaskan salmon fins, intestines, and other fish, legally unloaded into the ocean. I hand-signaled my partner, pointed up at the schooling swarm, and then shook my head to let him know that I wasn’t very happy with his low-ball estimate.

Every year, tons of fresh salmon are flown and shipped from Alaska to the lower 48 states. Before they’re flown south, the fish are sliced and diced into ready-to-cook filets, creating “inedible” fish waste. Under the Clean Water Act, people and industries handling fish and fish products are allowed to dump some of their waste back into the sea. But the EPA regulates these discharges with help from the states to ensure that waste does not degrade waterways. We all value our lakes, streams, and oceans, and the Clean Water Act helps to protect them.

Fish waste is often discharged down a permitted outfall, which is a pipe carrying waste into the ocean. This creates a ‘zone of deposit’ or ZOD on the seafloor. Life on planet ZOD is pretty limited—bacteria that live without oxygen predominate, and hydrogen sulfide gas (the stuff that smells like rotten eggs) is belched out occasionally. Outside of the oxygen-free zone, the ZOD attracts scavengers. On that surprising first dive, so many small dogfish filled the water that they were getting caught between my legs, in the crooks of my arms, and bumping me from every other direction to see if I had a handout—or if I were a handout!

The ZOD is supposed to be confined to a small area on the seafloor, but it often extends much further than allowed: some waste piles, though permitted only to an acre or less, extend to dozens of acres and may even grow so tall that navigation by boats can be obstructed. This is where inspections come in. I and other EPA divers check the type of waste being discharged and map out the size of the ZOD, to make sure it doesn’t cover more seafloor than allowed.
 

When the EPA finds that a company is violating its permit, one option is to ask its managers to recycle their waste. Seafood waste can be made into a variety of products from salmon cakes to gourmet pet food to high value fertilizer. Many fish processing plants have jumped into recycling technology, making good use of nearly all their “waste”. That’s a lot of happy kitties (although the dogfish might not appreciate the loss in food)!

Recycling fish products instead of creating a permitted outfall is better for ecosystems. To encourage this behavior, ask at your grocery store if the seafood company you’re buying from recycles their waste. Buy recycled products whenever possible—voting with your dollars makes a definitive statement that you want to see more recycling!

Read more about the latest in EPA scientific diving at the EPA Divers Facebook page.

About the AuthorSean Sheldrake is part of the Seattle EPA Dive unit and is also a project manager working on the Portland Harbor cleanup in Oregon.  He serves on the EPA diving safety board, responsible for setting EPA diving policy requirements.  

Editor's Note: The opinions expressed here are those of the author. They do not reflect EPA policy, endorsement, or action.

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It All Starts with Science: Answering Questions about Mining in Bristol Bay, Alaska

Considering the scope of resources in Bristol Bay – a 37.5 million average annual run of sockeye salmon; $480 million in ecosystem-generated economic activity in 2009; 14,000 full- and part-time jobs from that activity; and 11 billion tons in potential copper and gold deposit – it is no wonder there was significant interest in an EPA science assessment to understand how wild salmon and water resources in the Bristol Bay watershed might be impacted by large-scale mining operations. The public comment periods generated 230,000 responses on the first draft of the assessment, and 890,000 on the second.

This week, after reviewing all those comments and formal peer review by 12 scientists with expertise in mine engineering, fisheries biology, aquatic biology, aquatic toxicology, hydrology, wildlife ecology, and Alaska Native cultures, EPA released its final report, “An Assessment of Potential Mining Impacts on Salmon Ecosystems of Bristol Bay, Alaska.”

More than three years ago, several Bristol Bay Alaska Native tribes requested EPA take action under the Clean Water Act to protect the Bay and its fisheries from proposed large-scale mining. Other tribes and stakeholders who support development in the Bristol Bay Watershed requested EPA take no action until a permitting process begins.

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Editor's Note: The views expressed here are intended to explain EPA policy. They do not change anyone's rights or obligations.

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Bristol Bay: The Heart of the Watershed and Its People

By Dennis McLerranMcLerran

Last week my colleague Nancy Stoner wrote about our recent visit to Bristol Bay, Alaska. I would also like to share my perspective about this incredibly valuable trip and our ongoing Watershed Assessment to examine the potential impacts of large-scale development – particularly mining.

On our first stop, tribal leaders and community residents from Iliamna, Newhalen and Nondalton, shared their perspectives about their subsistence way of life, the fishery, and the proposed mining activities in the area north of Iliamna Lake. We met with Pebble Partnership executives for an update on environmental studies and mine planning, and flew to the prospect site to see the exploration activities firsthand.

We then flew to Ekwok along the Nushagak River. People in the village were excited because the first king salmon had just been netted, and the sockeye fishing season was just a few weeks away. Residents spoke eloquently about their concerns that mining could cause them to lose the fish and game they have depended on for generations. After the meeting we boarded a jet boat to New Stuyahok. Many elders attended this meeting and gave us a strong sense of the connection between the village, the river and its resources. We travelled up the Mulchatna River to Chief Luki’s cabin site, and hiked up a nearby hillside to look across the vast stretch of tundra. We dined on traditional foods and then got back in the boat to travel upriver to Koliganek.

The following morning, we met for several hours with a large group in Dillingham that included Bella Hammond, wife of former Alaska Governor Jay Hammond, current and former Alaska legislators, tribal elders and many local residents and fishing permit holders. We listened intently as the group expressed strong concerns about resource development and protection of the Bristol Bay salmon.

The trip took us to the heart of the watershed and gave us a rare opportunity to travel to the villages that are most concerned about our Watershed Assessment. We heard from supporters of mining development as well as those who believe large scale mining would be inconsistent with the preservation of subsistence ways of life and the Bristol Bay fishery.

The ability to see the watershed, the villages, Bristol Bay and the proposed resource development area firsthand is something that could never be matched by pictures or PowerPoint presentations. It is a trip I will never forget.

About the author: Dennis McLerran is the Regional Administrator for EPA Region 10, which serves the people of Alaska, Idaho, Oregon, and Washington.

Learn more about EPA’s Watershed Assessment of Bristol Bay

Editor’s Note: The opinions expressed in Greenversations are those of the author. They do not reflect EPA policy, endorsement, or action, and EPA does not verify the accuracy or science of the contents of the blog.

Editor's Note: The opinions expressed here are those of the author. They do not reflect EPA policy, endorsement, or action, and EPA does not verify the accuracy or science of the contents of the blog.

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Delusional Reality About West Coast Salmon

Several links below exit EPA Exit EPA Disclaimer

About the author: Dr. Robert Lackey is a senior scientist in EPA’s Office of Research and Development’s laboratory in Corvallis, Oregon. He has been involved professionally with West Coast salmon issues for 44 years and was awarded EPA’s highest award, the Gold Medal, for his salmon work.

Photo of Bob LackeyOne of my favorite fictional characters is detective extraordinaire Joe Friday. Joe demanded and provided “just the facts” as he sleuthed his way through the gossip and hearsay to winnow out the truth. Scientists responsible for informing the public and policy makers about ecological policy issues should attempt to do the same — just the facts — the straightforward, sometimes unpleasant realities.

A case in point: The 2008 collapse of salmon runs along the West Coast is being chronicled in major national newspapers, with headlines proclaiming “Disaster Strikes West Coast Fishermen,” “Worst Salmon Runs in History,” and “Agencies Baffled by Unexpected Salmon Collapse.”

Let’s apply Joe Friday’s “just the facts” approach to the wild salmon situation to see what society might expect in the future.

Fact 1: Wild salmon in California, Oregon, Washington, Idaho, and southern British Columbia are in serious trouble. Most runs in the Western U.S. are at less than 10% of their pre-1850 levels. Over two dozen are listed as threatened or endangered, with many more likely to follow unless something changes.

Fact 2: Meager salmon runs along the West Coast are nothing new. The decline in wild salmon numbers (PDF) started with the California gold rush in 1848; causes include water pollution, habitat loss, over-fishing, dams, irrigation projects, predation, and competition with hatchery-produced salmon and non-native fish species.

Fact 3: If society wishes to change the future for wild salmon, something must be done about the unrelenting growth in the human population level along the West Coast (California, Oregon, Washington, Idaho, and British Columbia). By 2100, there could be 200 – 250 million people in the region: a quadrupling by the end of this century — barely 90 years from now.

Fact 4: If the human population levels increase as expected, options for restoring salmon runs to significant, sustainable levels are greatly limited. Consider the demand for houses, schools, stadiums (PDF), expressways, automobiles, malls, air conditioning, drinking water, consumer goods, golf courses, and sewer treatment plants. Society’s options for sustaining wild salmon in significant numbers would be just about non-existent.

Whatever policy makers propose to do about the 2008 collapse of West Coast salmon runs, these four facts cannot be ignored. Policy makers should demand from scientists realistic and honest assessments (PDF) of the current and future conditions for salmon.

Joe Friday was a tough, no-nonsense professional. Those of us who provide the public and policy makers with the best available information about salmon ought to follow his lead: “just the facts”.

Editor's Note: The opinions expressed here are those of the author. They do not reflect EPA policy, endorsement, or action, and EPA does not verify the accuracy or science of the contents of the blog.

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