Chad Martel

Chad Martel, Hoopa Valley Tribe Fisheries Department

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Chad obtained his undergraduate and graduate degrees from Cal Poly Humboldt where he focused on marine and estuarine fish. Currently, he works with the Hoopa Valley Tribal Fisheries Department as a Habitat Biologist. His focus with Hoopa has been on smaller scale restoration projects, juvenile outmigrant monitoring both on and off the reservation, and habitat monitoring projects.

2024 Science Symposium Presentation

Day one of the Trinity River Restoration Program Science Symposium covered Fish Populations. Listen in as Chad Martel, Hoopa Valley Tribe Fisheries Department presents, “Trinity River outmigrant survival study.”

Bill Pinnix

Bill Pinnix, Supervisory Fish Biologist – U.S. Fish and Wildlife Service – Arcata

Bill has been studying fish and their habitats in the Humboldt Bay area since 1993. His early career pursuits included marine fish ecology and the importance of marine zooplankton to fish populations. Bill graduated from Humboldt State University in 1995, and moved to Seattle to work on his Master’s degree at the University of Washington (UW) School of Fisheries.

At UW Bill worked with the Joint Institute for the Study of Atmosphere and Ocean / Pacific Northwest Climate Impacts Group to understand climatic forcing mechanisms of the nearshore marine environment and the resulting impacts to marine survival of coho salmon to improve Washington Department of Fish and Wildlife’s coho salmon harvest forecast model. Following completion of his Master of Science degree from UW, Bill moved to Newport Oregon to work as a faculty research assistant to research climate forcing mechanisms on early life history of sablefish, looking closely at otoliths to try and find a ‘climate signal’. Bill served a brief stint with the National Marine Fisheries Service working with zooplankton before moving back to Eureka to work for the U.S. Fish and Wildlife Service in late 2001. Bill’s duties with The Service began with monitoring juvenile fishes, involved work with rotary screw traps and acoustic and radio telemetry, and currently serves as the lead of the Monitoring and Assessment division of the Fish and Aquatic Conservation Program at the Arcata Fish and Wildlife Service. Bill serves on multiple technical advisory committees and is especially proud of his work with the Pacific Marine and Estuarine Partnership. Bill loves to be outdoors with his wife Jenny and puppies Frankie and Beans, and when conditions allow can be found recreating on or in the ocean.

2024 Science Symposium Presentation

Day one of the Trinity River Restoration Program Science Symposium covered Fish Populations. Listen in as Bill Pinnix, Supervisory Fish Biologist – U.S. Fish and Wildlife Service – Arcata presents, “Status and trends of juvenile and adult Chinook salmon in the Trinity River.”

Andrew Paul, Ph.D.

Andrew J. Paul, Ph.D., Adjunct Professor, Department of Biological Services – University of Calgary, Canada

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Dr. Andrew Paul has been working as an aquatic ecologist in western Canada for 35 years. His work has encompassed the fields of conservation biology, community restoration, non-native species invasions, population ecology and river ecology. Andrew uses quantitative methods to aid in understanding ecological patterns or processes and has worked with the Theoretical Population Dynamics Group (University of Amsterdam) and the Fisheries Centre (University of British Columbia). Andrew spent 15 years with Alberta Fish and Wildlife studying environmental flows and now works with Alberta’s Chief Scientist to support scientific excellence in government. Andrew is an adjunct professor at the University of Calgary (Dept. of Biological Sciences).

2024 Science Symposium Presentation

Day one of the Trinity River Restoration Program Science Symposium covered Fish Populations. Listen in as Andrew J. Paul, Ph.D., Adjunct Professor, Department of Biological Services – University of Calgary, Canada presents, “Importance of experimental design to understanding aquatic ecosystems: how good intentions and experience can be the enemy of knowledge.”

Kurt Fausch, Ph.D.

Kurt Fausch, Ph.D. Professor Emeritus, Department of Fish, Wildlife, and Conservation Biology, Colorado State University

Kurt Fausch is Professor Emeritus in the Department of Fish, Wildlife, and Conservation Biology at Colorado State University, where he taught for 35 years. His research collaborations in stream fish ecology and conservation have taken him throughout Colorado and the West, and worldwide, including to Hokkaido in northern Japan. His experiences were chronicled in the PBS documentary RiverWebs, and the 2015 book For the Love of Rivers: A Scientist’s Journey which won the Sigurd F. Olson Nature Writing Award. He has received lifetime achievement awards from the American Fisheries Society and the World Council of Fisheries Societies, and the Leopold Conservation Award from Fly Fishers International.

2024 Science Symposium Presentation

Day one of the Trinity River Restoration Program Science Symposium covered Fish Populations. Listen in as Kurt Fausch, Ph.D., Professor Emeritus, Department of Fish, Wildlife, and Conservation Biology, Colorado State University presents “What is essential about rivers for fish and humans? Lessons on connectivity and connections from four decades.”

Presentation Coming Soon!

2024 Science Symposium – Day 3

The final day of the symposium focused on the physical environment that underpins the complex riparian and aquatic river ecosystem. We learned that while the Trinity River is actually used as an example for successful implementation of a functional flows approach to streamflow management, we are still missing some key components of a functional flow hydrograph that are essential to optimizing the physical and ecological processes of the river.

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Day 3 – Physical Channel Form presenters and organizers. From the left; Conor Shea, Dave Gaeuman, John Buffington, Scott McBain, Kiana Abel, Todd Buxton, Sarah Yarnell, Daniele Tonina and Mike Dixon.

Contrary to the prevailing folk wisdom in salmonid streams that all fine sediment in salmonid streams is bad, it was revealed that having too little fine sediment can impede the movement of larger gravels, and that having river flows match tributary flows is important to moving fine sediment in a way that is healthy for the river, rather than harmful. There were insights about what we know about how gravel routes through the upper river and what that means for our approach to sediment augmentation. A uniquely interdisciplinary presentation focused on how flow management influences where riparian plants grow, spurring conversation about how varying base flows could promote willow growth across different active channel widths, which could provide roughness and improve sediment sorting and storage. The takeaways really came down to this; we can’t have healthy fish and other wildlife populations without process, and we have learned a lot about how to improve those processes.

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Dr. Tonina holds the mic during the panel discussion on day three of the 2024 Science Symposium.

The panel discussion at the day’s conclusion was moderated by SAB member John Buffington, Ph.D.. The questions from the audience were stimulating and the panelists conversation informative. The discussion can be viewed in its entirety by clicking the YouTube link below.

Day 3 Panel Discussion on Physical Channel Form.

Presentation videos are being edited to include presenter slides – we will be uploading them to the 2024 Science Symposium page as they become available. For a list of power point presentations, please click here.

2024 Science Symposium – Day 2

Day 2 presenters for Habitat, Flow and Temperature. From the left, Kyle De Juilio, Derek Rupert, Eli Asarian, Seth Naman, Don Ashton, Todd Buxton and John Hayes.

Day two of the 2024 Trinity River Restoration Program Science Symposium was intended to explore the function of the Trinity River and other lotic (rapidly moving fresh water) systems. With an emphasis on creating a common understanding that can be applied to management in the future. Much has been learned in the relatively young field of river restoration over the last few decades, and leveraging that learning is critical to successful restoration in our watershed and others.

The day started with new TRRP Science Advisory Board member and world renowned researcher, John Hayes, Ph.D.. Dr. Hayes presented on his work with salmonids in New Zealand to describe their flow requirements through numerical modeling of drifting macroinvertebrates and drift foraging behavior. These innovations have changed the way managers think about the effects of flow management on salmonid populations. 

Dr. John Hayes talks about attending the Trinity River Restoration Program 2024 Science Symposium. Dr. Hayes is a new member of the Program’s Science Advisory Board and he opened Day 2 presentations with a talk titled, “How flow affects aquatic invertebrate habitat and drift, and salmonid net energy intake and instantaneous carrying capacity.

We had additional talks on temperature and thermal diversity from Eli Asarian (Riverbend Sciences) Klamath Basin water temperature expert along with Todd Buxton, Ph.D. (TRRP) a physical scientist and an accomplished fisheries researcher. We heard from regional reptile and amphibian expert, Don Ashton (McBain and associates) about the decades of research on the Trinity River and the impacts that flow management have had on these important indicator species of ecosystem health.

Don Ashton (McBain and associates) during his presentation about the decades of research on the Trinity River and the impacts that flow management have had on reptiles and amphibians.

Finally, we heard from Seth Naman, currently with NOAA Fisheries and long time Klamath Basin Fisheries researcher, and Derek Rupert, currently with Reclamation and former USFWS Fisheries Biologist on the Trinity River, about 2 proposed methods to manage flow releases year-round on the Trinity River and Clear Creek respectively. These proposed methods rely on seasonal and annual patterns of run-off to restore the functionality of the river to that which the species evolved with to ensure reproductive success and productivity.

Together this suite of talks described our current understanding of how cold-blooded species feed and behaviorally regulate their body temperature in regulated and unregulated rivers. As well as the known and suspected impacts of flow and temperature management and proposed methods to reduce impacts and improved function of the environments we seek to restore.

The panel discussion at the day’s conclusion was moderated by SAB member and Fisheries Researcher from Canada, Andy Paul, Ph.D.. The conversation was stimulating and informative and can be viewed in its entirety by clicking the YouTube link below. The direct communication between SAB members, scientists within the Program, managers, and the public is critical to moving management forward together to benefit the resource for all.

Day 2 Panel Discussion on Habitat, Flow and Temperature.

Presentation videos are being edited to include presenter slides – we will be uploading them to the 2024 Science Symposium page as they become available. For a list of power point presentations, please click here.

2024 Science Symposium: Day 1

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The first day of presenters and organizers pose for the 2024 Trinity River Science Symposium. Left to Right: Ken Lindke, Chad Martel, Kurt Fausch, Bill Pinnix, Kiana Abel, Andrew Paul and Nicholas Som.

The first day of the 2024 Trinity River Restoration Program Science Symposium was a great start to the week. Science Advisory Board members Kurt Fausch, Ph.D. and Andrew Paul, Ph.D. (link to bios) started the day by sharing their sage wisdom from decades of scientific practice and learning.

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Dr. Fausch took us across the Pacific Ocean to share his experiences with early groundbreaking work on the interconnectedness of streams and riparian ecosystems with colleagues in Hokkaido Japan, reminding us that the human connection to rivers and fish is, perhaps, more important than any scientific finding we can achieve.

Next, Dr. Paul rounded out the morning with a lesson on study design and a cautionary tale on how good intentions can sometimes lead us astray, while sound, well formulated sampling designs can buffer against unintended missteps.

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Dr. Andrew Paul speaks to the audience Tuesday morning.
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After lunch we welcomed Bill Pinnix from US Fish and Wildlife Service. Pinnix brought the audience back to the Trinity River by showing one of the notable successes of the Restoration Program, a significant increase in juvenile Chinook Salmon production since implementation of the Record of Decision in 2000. Pinnix noted that, in spite of successes with juvenile outmigrants, results for adult Chinook Salmon returns have been mixed.

The rest of the afternoon was dedicated to a short list of the challenges that juvenile salmonids face in their journey to the ocean and back. Chad Martel of the Hoopa Valley Tribal Fisheries Program described a multiagency, multiyear study of juvenile outmigration survival from Lewiston Dam to the Klamath River Estuary, where survival has so far shown to be higher than most area biologists expected.

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Chad Martel points at one of his slides during his presentation on Tuesday, April 30.

Dr. Nicholas Som from US Geological Survey and Cal-Poly Humboldt taught us about the fish parasite Ceratanova shasta, the history of learning in the Klamath basin, and successes in translating scientific discovery into water management implementation.

Finally, renowned ocean fish ecologist Nate Mantua, Ph.D. from the National Oceanic and Atmospheric Administration provided a glimpse of insight into the complex world of Pacific Ocean circulation patterns, tropical teleconnections, coastal upwelling, food web dynamics and the perils and opportunities that face young salmon as they survive, die, grow and mature to return to the Klamath river and complete their lifecycle.

Dr. Nate Mantua discussed the climate and changing ocean conditions on Tuesday, April 30.

The evening was rounded out with a panel discussion held at the Lewiston Hotel, Restaurant and Dance Hall which was moderated by Science Advisory Board member John Hayes from the Cawthron Institute in New Zealand. The 90-minute discussion provided insightful questions and educational dialogue between attendees and panelists and we thank everyone who was able to participate.  

Panelists get ready for the discussion at the Lewiston Hotel on Tuesday evening.

Presentation videos are being edited to include presenter slides – we will be uploading them to the 2024 Science Symposium page as they become available. For a list of power point presentations, please click here.

Featured Article: The Trinity Watershed Basin’s Water Year Forecast & Local Snow Surveys

Many Trinity County residents are attuned to the annual water year forecasting prepared by the California Department of Water Resources, also known as the Bulletin 120 or B-120. Every year, the department gathers real time water accumulation information, snowpack data and uses modeling to forecast what to expect for the major snow bearing watersheds in California. The water bean counting starts October 1 (the nominal beginning of California’s wet season) with a final determination April 10 each year. The forecasts are broken up into several regions throughout California with the Trinity River at Lewiston Lake forecast filed under the North Coast Hydrologic Region.  The ultimate goal of the B-120 is to value expected amounts of water inflow to storage locations around the state. These data makes it possible for water managers to make local informed decisions about potential floods, the amount of water that can be released from reservoir systems, as well as what type of dry season residents and fire agencies could expect within their regions.

Each year, the Watershed Research and Training Center along with the U.S. Forest Service – Shasta-Trinity National Forest conduct monthly snow surveys at specific locations in the Trinity Alps which are a part of the statewide California Cooperative Snow Survey program. Together these local organizations help the California Department of Water Resources forecast the quantity of water available for our watershed each water year. Listen into Josh Smith, Watershed Stewardship Program Director for The Watershed Center talk about their efforts in collecting this important yearly data.

For the Trinity River Restoration Program, the April B-120 forecast determines the water year allocation for our yearly restoration flow releases, which were outlined in the 1999 Flow Study Evaluation and adopted in the 2000 Department of Interior – Record of Decision. These five water year types that determine the amount of water released to the river from year to year are categorized as Critically Dry, Dry, Normal, Wet and Extremely Wet. You can see the relative allocation for restoration purposes in the table below.

It is interesting to note that the State’s April B-120 has only overpredicted the water year type once, in 2008.  Currently the allocation for river restoration is the only conditioned amount of water released from Trinity & Lewiston Reservoir; where the Restoration Program’s yearly allocation is limited by water year type, the Central Valley Project can divert any amount in any water year type, usually diverting less in wetter years and more in drier years. Safety of dams releases and water releases to the Trinity River for ceremonial purposes or for Klamath River mitigation purposes are not part of the restoration release volume.

Josh Smith and Michael Novak in Bear Basin during the annual snow survey in 2020. Photo by Dillon Sheedy.

As mentioned above the State’s forecast uses a few different methods to determine how much water to expect as inflow into Trinity & Lewiston Reservoir. The most story-worthy data collection type are the on-the-ground, snow surveys which are conducted during a short window every February, March, April and May. The Trinity Alps snow surveys are led by two agencies: The U.S. Forest Service who motor in via snow Cat to several locations in the Trinity Alps Wilderness, and an expert group of backcountry cross country skiers led by The Watershed Research and Training Center. There are nearly a dozen survey courses established throughout the Trinity River watershed and these sites have been measured in exactly the same locations since the 1940s.

A long metal tube is pushed down through the snow to the ground, capturing the depth of the snow in the core of the tube. This photo was taken of Ben Letton by Josh Smith during the March 2021.

Each year The Watershed Center sends out a small team of between two and four backcountry skiers to travel through the Alps Wilderness and measure snowpack at three survey courses: Shimmy Lake, Red Rock Mountain, and Bear Basin. Once the team reaches a survey location, they drive a specialized aluminum tube tool called the Mt. Rose Sampler, into the snowpack until they hit ground. “It takes a few times to get used to doing it,” says Josh Smith who has been conducting surveys in the Alps since 2011, with the first full recorded season in 2012. The surveyors use the tool to measure the height of the snow, then carefully extract the tube from the snowpack and weigh the snow-filled tube using a handheld scale. These measurements allow the surveyors to calculate the Snow Water Equivalent in designated transects within the three courses for which their team is responsible for. The State uses the hand measurements from the snow survey teams to bolster additional data taken from unmanned sensors located across and just outside of the watershed. These data sources together feed into a model that predicts the volume of water that will flow into Trinity Reservoir that year.

The Mt. Rose Sampler tube is being weighed on a specialized handheld scale. Using the height and weight of the snow, surveyors are able to calculate the Snow Water Equivalent (SWE).

A great deal of preparation and expertise goes into the Trinity Alps Snow Survey and participation is not for the faint of heart. When asked if the survey team has had any injuries Smith explained, “mostly broken will, oh, and lots and lots of blisters.” The crews aim for good weather days but do encounter a variety of winter weather patterns that exemplify California’s highly variable winter weather conditions, including blizzard conditions, wet and heavy snowpack, avalanche conditions, and melting snow that leads to flooding creeks.

“These are not groomed trails, and the crews switch off being the lead – when the snow is deep or heavy it’s not easy breaking trail, so we try and spread out that responsibility, especially when trying to conserve energy throughout the multi-day survey,” explained Smith.

That said, the Watershed Center is looking for local Trinity County residents who believe they have a sufficient mental and physical stamina to participate in this long-standing Trinity County tradition. “We get a lot of calls from people who think this is right for them,” Josh continues, “most people only come out once, and then they are done. It’s a real suffer-fest.”

Nick Goulette and Michael Novak during a blizzard in 2019. Photo by Josh Smith, provided by The Watershed Center.

If you’d like to learn more, please reach out to Josh Smith at the Watershed Training and Research Center by calling (530) 628-4206.

Program Update: April 2024

While it has not been a focus of the TRRP for many years, infrastructure improvement was one of the foundational tasks that was laid out in the 2000 Trinity River Mainstem Fishery Restoration Record of Decision. Years of low, predictable flows had led riparian property owners to develop very close to the river’s edge. In order to implement restoration releases, the TRRP has worked with willing property owners to upgrade or remove infrastructure that could be damaged by restoration flow releases as guided by the “maximum fisheries flow” boundary.

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A photo of the cleared River Acres parcel, post demolition, April 2024.

The maximum fisheries flow is an 11,000 cubic feet per second release from Lewiston Dam (the highest the program can target for restoration objectives) that coincides with a major spring storm event. In the program’s first decade, there was a big push to address permitted infrastructure to clear the floodplain for fisheries releases; we moved roads, replaced several bridges, upgraded dozens of septic and water intake systems, and relocated a house in Douglas City. Another house (391 River Acres Rd in Junction City) was identified as being inside of the maximum fisheries flow boundary, but the owners were not interested in improving or selling their home at that time.

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The River Acres House prior to removal, winter 2024.

The circumstances changed in the late 2010’s when the house sold to a new owner who used it as a fishing cabin and was very interested in finding a mutual solution that would benefit Trinity River fisheries. Together with engineers and architects the landowner and TRRP explored moving the house, building a levee, and elevating the living area with a flow-through bottom story. In the end, none of those solutions proved feasible due to flood concerns with adjoining properties and other constraints. The situation led the homeowner to decide to sell the house to the Bureau of Reclamation, who acquired the property in 2023.

In March of 2024, Cal Inc., a certified small business located in Vacaville, California was awarded the contract to demolish the 391 River Acres structures. Cal, Inc., specializes in general construction, abatement and remediation services, and environmental and safety training, and it took their professional staff only a few weeks to gather intel, test for lead and asbestos, and mobilize machinery, crew and subcontractors to begin the demolition.

Over the course of the week of April 8 the domestic water well and septic system was decommissioned, the structures and concrete pads were reduced to splinters and rubble, and an entire fence line of firewood was donated to a local charity. 

The first crunch of an excavator bucket flattening an outbuilding occurred Monday morning and by Friday a final few sweeps of a hard-tine rack flattening the vehicle tracks left from construction. The materials left were loaded into what amounted to 12 dumpsters and was hauled-off for proper disposal.

Over the course of the week many of the neighbors wandered over and reminisced about those who had called the River Acres house home (or home away from home) over the years.  They were understandably sad about losing a piece of River Acres history but were excited about the open space for their dogs and grandchildren to run and play in. We appreciate their tolerance of the noise, construction and extra visits these past few months. The project will be considered complete once the bare areas have been mulched and seeded, likely to be fully complete by the first of May.

Animal Spotlight: Benthic Macroinvertebrates

Benthic Macroinvertebrates

What are they and why are they important to river ecology?

Benthic: bottom-dwelling

Macro: see with the naked eye

Invertebrates: animals without backbones

Most of the life in rivers on any given day of the year are the small creatures that live out of the direct force of the river’s current, either attached to the rocks or wood, in spaces underneath or between pieces of gravel, or burrowed into silt. These animals include mussels, snails, worms, crayfish, and aquatic mites. But among all types of aquatic invertebrates, one class of animals stands out as the most diverse and complex – the insects.

An important term in river ecology is “benthic macroinvertebrate”, which refers to bottom-dwelling (benthic) animals without backbones (invertebrates), that you can see with the naked eye (macro). Ask a fly fisherman what trout and steelhead eat, and they’ll probably tell you salmon eggs if they’re available, sometimes other fish, occasionally snails, worms, grasshoppers or ants that fall into the stream, and with most frequency aquatic insects. Aquatic plants and algae photosynthesize energy from the sun. These plants then feed aquatic insect which in turn become an important energy for fish. Many insects have specialized mouthparts and behaviors to scrape algae and diatoms from rocks. Others feed themselves by shredding detritus (organic material that collects in rivers), or by straining food particles from the river’s flow, or by attacking and consuming other invertebrates.

Salmonid lifecycle and feeding

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The mouths of small salmon fry are very small, and when their nutrient sac is no longer providing food prime food sources are plankton such as Daphnia (which could be considered “micro” invertebrates), small insect larvae such as chironomids (better known by their common names as midges or gnats) and young mayfly larvae such as baetids (known by fly fishermen as “blue-winged olives”).

Above, a chironomid larvae. Small and soft bodied, with generations as short as three weeks, this family of invertebrates rapidly colonizes seasonally flooded areas and provides excellent food for salmon and steelhead fry, as well as larger fish.

macroinvertebrates.org
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A larval giant salmonfly
These insects live for three years in the river before metamorphosing into adults. While growing, they mainly eat detritus (organic material that collects on the bottom of the river). Image credit: troutnut.com
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An adult giant salmonfly (Pteronarcys californica)
A large stonefly that inhabits the Trinity River. On the Trinity River, these insects ‘hatch’, or metamorphize into adults in the spring. Image credit: Google.com

Older fish, the size of trout or steelhead, readily eat the larvae of larger insects such as caddisflies and salmonflies. Most aquatic insects are very small when they hatch from their eggs, and grow into progressively larger individuals after shedding their exoskeletons – a process called ‘molting’. Each growth stage is called an ‘instar’, and as they grow, each instar provides different sizes of food for different sizes of fish. After a range from a few weeks (for chironomids) to a few years (for some stoneflies and caddisflies) the insect pupates (similar to a caterpillar in a cocoon) and metamorphoses into a winged adult. Most of these adults are short-lived. Mayflies and stoneflies, for example, don’t even have functional digestive systems. They only live long enough to mate and deposit eggs in suitable locations along a stream.

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A larval October caddis with a case made of stones glued together. While larger fish may eat these insects case and all, the high proportion of inedible material deters predators from eating them. October caddis generally spend two years in the river before they metamorphose into adults. They graze on algae and diatoms that cover rocks, but may also be observed feeding on dead salmon. Photo Credit: inaturalist.com
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An adult October caddis (Dicosmoecus spp), a large caddisfly that lives in the Trinity River. As their name suggests, these caddisflies metamorphose into adults in the fall, when they lay the eggs for the next generation. Photo credit: troutnut.com
A larval baetid (blue-winged olive) mayfly. Although this photo was taken in Montana, similar species inhabit the Trinity River. Baetids are generally multi-voltine (have multiple life cycles per year), and this, coupled with their small size, makes them ideal food for salmon and steelhead fry. There are over 1,000 species of Baetids worldwide, and they have a variety of feeding habits, but are generally good swimmers and move around the river bottom feeding on that algae and diatoms that grow on rocks. Photo Credit: Encyclopedia of Life
A male Baetis (blue-winged olive) mayfly. Baetid mayflies are common in dam-regulated river reaches. These mayflies can hatch spring through fall, and even sometimes in the winter.
Photo credit: troutnut.com

Macroinvertebrates and stream health

Many aquatic insects have very specific requirements for water parameters such as maximum temperatures, minimum dissolved oxygen, turbidity, pH, and salinity. These requirements make benthic macroinvertebrates very good bioindicators of stream conditions. The orders Ephemeroptera (mayflies), Plecoptera (stoneflies), and Trichoptera (caddisflies) are famous for requiring cold and clean water to thrive. In contrast, Chironomids, which belong to the order Diptera along with common houseflies, vary in their requirements depending on the species.

Stream ecologists can collect a sample of benthic macroinvertebrates and identify the species in the sample. In turn, the insects captured can then tell them about the condition of the stream. For example, if the sample contains a high proportion of individuals in the orders Ephemeroptera, Plecoptera, and Trichoptera, this indicates that the water quality is high. If the sample contains mostly species that live out their life cycle in just a few months, such as many species of Baetis and Chironomidae, this indicates that the water quality may change significantly between seasons. If the sample contains many species that have multi-year life cycles, such as salmonflies and October caddis, this indicates that water quality remains high throughout the year on a consistent basis.

The next time you visit the Trinity River, look around for aquatic macroinvertebrates. You might see cased caddisflies clinging to small cobbles. Turn one over, and you are likely to see mayfly larvae clinging to the bottoms. Look for the shed exoskeletons of stonefly pupa on branches and stems near the water’s edge. Look further to see if you can observe a trout or steelhead sipping adult insects off the surface as they lay eggs and complete their cycle of life.

James Lee, MS – Implementation Branch Chief

James Lee grew up near Redding, Ca, but his heart has always been in The Trinitys, where he chased tadpoles, salmon, deer, and gold nuggets for much of his youth. This love of the outdoors turned into an interest in managing fish, wildlife, water, timber, and other natural resources.