Bug of the Month: Isonychia mayflies

Posted on October 15, 2024September 12, 2025 by Kiana Abel

Isonychia mayflies

You may have noticed a rather large insect fluttering down the river during the months of September and October. These insects are mayflies from the family Isonychiidae (eye-son-nic-ee-uh-day) (known in the fly-fishing community as Mahogany Duns or Slate Drakes). Isonychiidae mayflies are one of the largest, if not the largest mayfly found in the Trinity River.

Mayflies are unique in that they have two adult stages in their lifecycle while all other insects have one. The sub-imago stage (dun if you’re a fly fisherman) is a non-reproductive winged stage. The sub-imago stage typically only lasts a few hours as the mayfly molts one more time to become a fully reproductive adult. The final stage is known as the imago (spinner in fly fishing terms). The imago’s sole job is to reproduce. In fact, mayflies do not have functional mouthparts as adults which means they can only live for a short time.
Their scientific name (Ephemeroptera) attributes this fact. Ephemera comes from Latin and Greek meaning “daily” or “lasting a day” while ptera comes from Latin meaning “winged”. Keep a lookout for these “briefly winged” insects over the next month.

Isonychiidae mayflies usually live an entire year in the river as nymphs before swimming to the edges of the river, crawling out of the river on a rock, and emerging into their sub-adult stage. As adults, they typically only live for a day or two as their only job is to mate, lay eggs, and then die. Isonychiidae mayflies are noted for their large size compared to other mayflies and for their unique swimming ability. They are very adept swimmers and use their swimming prowess to capture their prey. They also have fine hairs on their forelegs which trap algae and other detritus which they then consume. The nymphs are a very strange looking (compared to other mayflies) and are readily identifiable by their elongated shape and ‘racing-stripe’ down their backs. Looking closely, the hairs on their forelegs become readily apparent and they are very easy to identify for any aquatic entomologist.

Isonychiidae mayflies are unique to the Trinity River with other populations scattered across northern California. The nearest population is found in the Pit River, but are rare there. The population in the Trinity River seems to be thriving and right now is the best time to see both the nymphs and adults. Look for the nymphs along the streambanks where they will look like small fish darting between the rocks. You will notice their shed exuviae (exoskeletons) attached to rocks. Adults can be found in the early afternoon fluttering in the air above the river. They seem to be more common in the area between Junction City and Cedar Flat.

Chris Laskodi, M.S., Fish Ecologist – Yurok Tribal Fisheries Department

Chris serves as the fish biologist/ecologist for the TRRP in the program’s Science branch. Chris has worked on the Trinity River since 2015, previously serving as a fish biologist for the Yurok Tribe and a fisheries technician for the US Fish & Wildlife Service. Chris holds a B.S. in Wildlife, Fish and Conservation Biology from the University of California, Davis and a M.S. in Aquaculture/Fisheries from the University of Arkansas at Pine Bluff. In his free time, Chris enjoys taking friends and family fishing on one of the many watercraft available to him.

Blue Elderberries (Sambucus nigra ssp. caerulea)

Posted on October 15, 2024April 29, 2025 by Kiana Abel

Blue elderberries, native to California, grow throughout the Northwest and are found here in Trinity and Humboldt Counties. These trees are known for their dainty elderflowers, nutritious elderberries, and hard, hollow wood. Indigenous people have long maintained relationships with elderberries. This food source carries medicinal benefits, famously made into elderberry syrup to promote a healthy immune system and
fight respiratory illnesses.

Photo adapted from Pinnacles National Park, National Park Gallery.

Animals, too, enjoy the berries as they ripen in the summer months. Elderberry trees serve as habitat for native bees and the valley elderberry longhorn beetle, because of the spongy tissue of their twigs. This pithiness also makes the wood uniquely amenable to crafting cultural materials, like arrows and flutes. Tribal practices, like cultural burning, ensure longevity and health of elderberry bushes.

What’s in a name?

Local Indigenous languages all have names for elderberries

Ch’iwhiwh
yúxaas
ta’amo’ ‘wer-nerh
luu-k’vm’

In Hupa, ch’iwhiwh means elderberries. Much like German, Hupa words build description. So ‘elderberries’ translates literally to ‘what one sips through,’ and bears information about how the wood was used.

Yúuxas, in Karuk, means elderberry. Yúuxas ánav means elderberry medicine.

In Yurok, elderberries is ta’amo’ ‘wer-nerh. Ta’amo’ meaning elderberry bush, and nerh a shortened form of nerhpery, berry.

In Tolowa, blue elderberry is luu-k’vm’ and red elderberry is chvn-su’lh.

Indigenous plant names reflect the relationship that group has built with that plant. Some ask, why learn a lesser spoken language? Here is one of the many reasons to do so. Indigenous languages have grown around the environments their speakers lived in, and the needs, wants, and interests of those speakers. So being, they are laden with Traditional Ecological Knowledge (TEK). The vocabulary regarding elderberries, for every Indigenous language, expresses a unique worldview. When used, the line between generations of elderberry enthusiasts flows complete.

When and How to Pick

Blue elderberries will flower in the late spring. This is a good time to identify the
locations of your nearby trees, as they won’t stick out quite so much once the flowers
fall. Flower heads can be clipped and dried. Elderflowers have a “diaphoretic quality
which lowers fever (LaPena et al.).” “Fresh or dried, the flowers are steeped to make a
potent tea to reduce fever (Karuk Tribe et al.).” It is pertinent to remove all stems, as
only the flowers and berries can be consumed. Berries will ripen later in the summer.
Typically, they ripen earlier inland and later on the coast.

I’m a beginner when it comes to picking elderberries. I’ve learned to only pick them when they’re ripe, when the whole flower head has dark blue or dusty grey berries. Any green berries should not be consumed. Go elderberry picking when there is lots of light and good visibility. To pick berries, it is practical to clip heads of berries and later comb them from their stems. As a general rule, don’t take too many from one tree. Leave some for the birds.

Elderberries can be used in an array of baked goods, syrups, and jams, and can also be dried and eaten. Avoid eating fresh berries as they can cause nausea, easily done as you might find they’re not so sweet.

Works Cited

Karuk Tribe. “Uxraah: Native Edible Berries.” G8L2NativeEdibleBerries_booklet, United States Department of Agriculture, nctcc.org/wp-content/uploads/2017/05/G8L2NativeEdibleBerries_booklet.pdf. Accessed 14 Oct. 2024.
LaPena, Sage, et al. “Indigenous Perspectives on Elderberry Uses – California Elderberries.” University of California Agriculture and Nature Resources, University of California, ucanr.edu/sites/Elderberry/Indigenous/Indigenous_perspectives/. Accessed 14 Oct. 2024.
Lowry, Judith Larner. “Blue Elderberry.” California Foraging, Timber Press, Portland, Oregon, 2014, pp. 57–59.
Unless otherwise noted, all photos were generously provided by Muriel Ammon.

Muriel Ammon

Muriel Ammon (Tsnungwe, Hopi) is a graduate of Dartmouth College and the Southwest Institute of Montessori Studies. Ammon is passionate about Indigenous language revitalization. She has many Hupa language teachers, including her dad, Verdena Parker, and Melodie George-Moore. One of her favorite parts of learning Hupa is connecting to the plants and animals in her backyard.

Other Work

Ammon, Muriel. News from Native California. Picking Elderberries Like Squirrels. September 20, 2024

Program Update: Implementation Branch

Posted on October 10, 2024April 29, 2025 by Kiana Abel

Civil construction of the Upper Conner Creek project has wrapped for 2024. Despite the late start, crews from the Yurok Tribe Construction Corporation (YTCC), The Yurok Tribe Fisheries Dept and Hoopa Roads Dept completed the first phase of construction in just under two months. Working exclusively on river left at river mile 78.3 in Junction City, the civil construction crews focused on lowering the 5.7 acre floodplain R1 and creating riffle IC-1.

Before construction, the R1 floodplain was a largely star thistle strewn meadow, which did not fully inundate until flows reached 11,000 cubic feet per second. The Hoopa Valley Tribe’s design team envisioned a lowered surface which targeted many inundation thresholds ranging from 500 to 3500 cubic feet per second. In three weeks time, employing excavators, bulldozers, articulating trucks and front end loaders crews excavated 65,000 cubic yards of earth from the non-functional floodplain to a spoils site further inland. The civil construction team added 300 plus pieces of large wood throughout the floodplain which enables the creation of habitat with a floodplain full of hydraulic diversity.

Stockpiles of large wood which were moved and placed in the newly lowered floodplain area to encourage slow waters and habitat creation.

Constructed of fish rock (5/8-5inches) and oversized sediment (5-12 inches) a riffle at the mouth of the new side channel was enhanced. The feature’s primary function is to add roughness to the river and raise the water surface elevation of the upstream waters to encourage wetting of the newly lowered floodplain on river left. In compliance with the projects permits, the civil construction team monitored water quality during this period of turbidity generation.

As the big yellow trucks demobilize, the revegetation crews start their work. In a temporary nursery onsite an assortment of native grasses, shrubs and trees sit soaking up sun and water while they wait for their turn to be planted. Aiming to wrap up efforts by December, the Hoopa Valley Tribal Fisheries revegetation team’s goal is to have the nursery stock entirely planted in the new floodplain and the spoils area stabilized with native grasses and straw.

As phase one nears completion, the TRRP’s Implementation Branch prepares for phase two. Just downstream, additional floodplains, riffles and improved river access spaces are all on the slate for construction in 2025. The prospect of building new recreational facilities alongside restored riverine habitat is work that we are proud to be part of!

Return to the October Newsletter

Bug of the Month: Common Green Darner

Posted on September 17, 2024April 29, 2025 by Kiana Abel

Common Green Darner

Anax junius

If you’ve been lucky enough to spend time on the Trinity River lately, you will notice a plethora of brassy-green colored dragon flies hovering above the river fervently darting to and fro. The species you are most likely viewing is the common green darner Anax junius. Common is in its name, and that is certainly the case, for this species of dragonfly is the most common and abundant throughout North America. The remainder of its common name, Darner, is given due to its resemblance to a darning needle a blunt-tipped larger needle used for repairing holes or tears in coarse knitted cloth.

Photo of a common green darner originally posted on iNaturalist, by chdphoto.

Dragonflies need water to reproduce. In the summer or early fall, common green darners seek riparian areas with slow water so they can mate and lay eggs in water-bound plant material. The female and male mate in an expertly posed “mating wheel” position – where the two are connected at their reproductive centers, the head of the female with the base of the male’s abdomen. The female’s abdomen is wrapped under the male so they can fly through the air, sometimes for several minutes. The female then unwraps her abdomen and lays eggs into the water while still attached to the male.

Photo: Female and male common green darners in the “mating wheel” position. David A. Hofmann, Source: NPS.org

A female common green darner (left) in tandem position with male (right) deposits eggs. Ken Slade, Source: nps.org

Eggs hatch into macroinvertebrates (tiny aquatic larvae) after about a week incubation period and then go through upwards of a dozen nymphic molts eating aquatic insects, small fish and even tadpoles as they grow. At the end of the transformational nymph stage, Anax junius, emerges from the water to undergo metamorphosis into a dragonfly from a crack in the exoskeleton.

Common green darner aquatic nymph. Douglas Mills. Originally posted by the National Park Service.

Once the wings are developed enough to fly the darner becomes a ravenous forager eating mosquitos, midges, flies, wasps, moths and other flying insects. This dragonfly species has two different population types, resident and migratory. Residents remain in the general area from which they emerge. For residents in the north, the adults mate and lay eggs in late July to August. The resulting offspring hatch and develop to immature dragonflies and then overwinter when temperatures drop.

Photo: Common green darnier catches a western swallowtail midflight. Bob Burns. Source: iNaturalist

Adults that migrate tend to arrive in the northern regions in the spring before any of the residents emerge. Migratory adults mate and lay eggs in June. The migratory dragonfly’s development stage is less than that of the resident variety (3-5 months versus the 11 months of the resident) and they do not overwinter as residents do.

Common green darner’s in September on the Trinity River. James Lee, Trinity River Restoration Program

Sources and Further Reading

Return to the September Newsletter

Featured Article: On Fish, and Fire.

Posted on August 23, 2024April 29, 2025 by Kiana Abel

Current conversations, media and our own experiences point to fire seasons that are far from ordinary. However, from dendrochronology (the study of tree rings) and other data sources, analysis find that prior to Euro-colonization, multiple millions of acres burned in on average in California. California’s ‘worst’ year in recent history saw about 4.5 million acres burned… which when comparing to historic averages would be within the ‘normal’ range (prior to Euro-colonization). In fact, tree ring scars show that many areas burned as frequently as every 5-10 years! Within the past century, our society along with forest managers have promoted and practiced a prohibition on abundant low-intensity fire, allowing unburned materials to build up in forests and woodlands that along with population increase has set the stage for the complicated relationship now experienced with wildfire.

Photo of Weaver Bally. — Smokey evening on Weaver Bally, August, 2018. Numerous trees in the photo were killed by the Helena Fire in 2017. Photo by E. Peterson.

Most of us who have lived any length of time in the rural west are stressed about wildfire through the summer and well into the fall. We endure smoke, dramatic headlines, helicopters flying over, evacuations, and too many of us witness damage to places we hold dear, including our own properties. Forests that have not yet been touched by fire are heavily loaded with dead wood, leaves, and duff ready to become an inferno at any moment. Where fires have burned there is often a heavy load of grasses, frequently mixed with the woody remnants of trees from the last fire. Everywhere we go, organizations involved with fire share dramatic photos of conflagrations consuming tall trees. And then we see flashfloods over fresh burns like with the McKinney Fire dumping sediments into rivers so thickly that it kills fish. It seems we are smothered in news of devastation from wildfire!

But let’s step back for a little perspective. Wildfire is nothing new to the west. Even before the first people set foot on these lands, our forests burned frequently from lightning strikes. These forests evolved with wildfires. As tribes developed, their people lived with wildfires, found prosperity from them, and learned to manage the land by intentionally setting fires.

Debris flow piled against a bridge on Little Humbug Creek, a tributary to the Klamath River, during the 2022 McKinney Fire. Photo by E. Peterson.

20^th century fire suppression has led to a build-up of dense forests, dead wood, leaves, and duff that fuel wildfires to be more destructive. Yet even with that build up, wildfires are often not all bad. Did you know that 66% of the 224,688 acre 2021 Monument Fire burned at low-intensity or lighter? Yes, the 34% of moderate- to high-intensity burn is visually striking as we drive highway 299, but that 66% of low-intensity improved the health and the resiliency of the forest. This mix of severities is typical for fires in our region. Even before fire suppression led to fuel loading, some amount of high-intensity burn was natural.

Photo: Debris flow piled against a bridge on Little Humbug Creek, a tributary to the Klamath River, during the 2022 McKinney Fire. Photo by E. Peterson.

This maintained relatively open forests and woodlands, and kept mountain meadows functioning as wetlands to feed headwater streams. Natural wildfires tend to become more intense as they go upslope. Look to the Trinity Alps where most mountain tops remain open and rocky. Many peaks have sufficient soil among the rocks to support trees, and some scattered trees growing near the top of Thompson Peak demonstrate that the Trinities have no true elevational tree line. But trees do grow slowly on those peaks and high intensity fires have historically happened often enough to keep those peaks mostly bare.

Carl Skinner presents 2023 Healthy Fire, Healthy Fish: Lessons From Fire History

From dendrochronology (the study of tree rings) and other data sources, most analysis suggest that prior to Euro-colonization, multiple millions of acres burned in on average in California. Our ‘worst’ year in recent history saw about 4.5 million acres burned… which would be within the ‘normal’ range prior to Euro-colonization. Tree ring scars show that many areas burned as frequently as every 5-10 years! But we stopped that abundant low-intensity fire, allowing unburned materials to build up in forests and woodlands, setting the stage for the conflagrations we now see.

Frequent low intensity fires keep those fuels cleared out forests and woodlands. It also helped keep them from getting too dense, promoting the growth of large older deep-rooted trees while minimizing the number of young upstarts that dry out the surface soils. By keeping pines and firs out of oak woodlands, these fires promoted habitat for deer and other wildlife. For these reasons, tribes managed the lands in California with fire.

Smoke has a surprising value too! Although unpleasant to our lungs, smoke cuts the intensity of sunlight hitting the ground. Not only does it cool air temperatures during summer afternoons, it also cools the water in our streams and rivers. Local research in the Klamath/Trinity River system found that smoke can cool our rivers by 2.4°C (4.3°F). That difference can be critical for Spring-Run Chinook hanging out in deep pools in the middle of summer! There is a lot of data to suggest that these rivers once had more Spring-Run Chinook than Fall-Run. It would be interesting to know how much the millions of acres burning each year contributed to the abundance of Springers back then!

Photo: Smoke on the Trinity River near Junction City, August 2021. Photo by E. Peterson.

So one of the big questions of our time is… how do we get back to healthy systems that function well (and safely) with fire?

References and Further Reading

Asarian, E. 2024. Water temperatures in the Klamath-Trinity Basin: flow, other key drivers, and climate change implications. Presentation on 2024-05-01, Science Symposium of the Trinity River Restoration Program. Riverbend Sciences, Arcata, California. Available: https://www.trrp.net/library/document?id=2647.
Salmonid Federation Restoration. Fire and Fish Workshop and Information
Scott L. Stephens, Robert E. Martin, Nicholas E. Clinton, Prehistoric fire area and emissions from California’s forests, woodlands, shrublands, and grasslands. Forest Ecology and Management. Volume 251, Issue 3. 2007. Science Direct.com
Trinity River Restoration Program Featured Article: Sediment and Summer Thunderstorms. The River Riffle, July 2023.
Gruell, George E. Fire in Sierra Nevada Forests: A Photographic Interpretation of Ecological Change Since 1849. Mountain Press Publishing Company, 2001
Fire in California’s Ecosystems. (2018). United States: University of California Press.

Return to the August Newsletter

Grey Pine (Pinus sabiniana)

Posted on August 20, 2024April 29, 2025 by Kiana Abel

Common names: Grey pine (most common), ghost pine, foothill pine, Sabine pine, bull pine or grey leaf pine.

Adapted to the long, hot, dry summers of our Mediterranean climate, the grey pine is endemic to California and prolificates within the ring of foothills that surround California’s Central Valley. It fairs well in rocky well-drained soils yet also grows in heavy, poorly drained clay soils. The species commonly occurs with Blue Oak (Quercus douglasii) which creates a unique partnership that is described as “Oak/Foothill Pine vegetation” and is indicative of the grey pine which provides a sparse overstory above the canopy of an oak woodland. The partnership in itself is the preferred habitat to black-tailed deer, California quail, as well as mourning dove and describes a characteristic within the California chaparral and woodlands ecoregion, of which Trinity County is part [1].

Photo published on The Gymnosperm Database. A tree at the Rancho Santa Ana Botanical Garden, California [C.J. Earle, 2004.04.13].

The grey pine is easily identifiable with pale grey-green needles that are sparse and a bit droopy. When looking from afar a grey pine is easily spotted by his smoky, wistful coloration. The structure of P. sabiniana tends to be a bit scrappy with its center trunk splitting sometimes several times, often bending every which way, versus holding a typical stature. Also easily identifiable are the seed cones which are among the largest produced by any pine species, when fresh weighing on average between 1-1.5 pounds. One particular source noted that, “The large, heavy cones resemble footballs covered with wooden spikes. It is best to avoid the pine groves on windy days.” [2] The cones tend to be full of sticky sap and are also home to a plethora of nutritious seeds enjoyed by many animal species, such as Steller’s jay, the scrub jay, grey squirrels and humans. The seeds have an impressive percentage of calories in the form of protein, fat and carbohydrates and provide several essential minerals to those who forage it [3].

This species is the principal host for the dwarf mistletoe Arceuthobium occidentale a perennial parasitic herb that is native to California [2]. Dwarf mistletoe is considered a disease that the tree can succumb to typically causing reduced tree vigor or death. If you have grey pines near your structures and the parasite is left uncontrolled, infection can increase sixty-fold within a window of 10 years [3].

Photo of dwarf mistletoe originally posted in the CalPhotos Database. Zoya Akulova 2008.

John Muir, describes this tree in the first chapter of My First Summer in the Sierra: “June 4. … This day has been as hot and dusty as the first, leading over gently sloping brown hills, with mostly the same vegetation, excepting the strange-looking Sabine pine (Pinus sabiniana), which here forms small groves or is scattered among the blue oaks. The trunk divides at a height of fifteen or twenty feet into two or more stems, outleaning or nearly upright, with many straggling branches and long gray needles, casting but little shade. In general appearance this tree looks more like a palm than a pine. The cones are about six or seven inches long, about five in diameter, very heavy, and last long after they fall, so that the ground beneath the trees is covered with them. They make fine resiny, light-giving camp-fires, next to ears of Indian corn the most beautiful fuel I’ve ever seen.”[2]

Photo published on The Gymnosperm Database. Small stand in the southern Santa Lucia Range, California [C.J. Earle, 2007.03.01].

The ethnobotanical uses of the grey pine are impressive with uses ranging from cultural to functional to nutritional. Although there are documented uses for all parts of the tree from sap to needle, primarily the seed gets the most attention. Seeds are noted to be gathered fresh, as well as roasted, boiled or pounded for porridge [5]. The hull of the seed is also used as a bead to decorate traditional dresses used for ceremony. Follow this link to read the lengthy, impressive list of all documented uses.

Photo published on The Gymnosperm Database. Ripe cone *in situ*; Bodfish area, California [C.J. Earle, 2014.01.17].

References & Further Reading

Return to the August Newsletter

Upper Conner Creek Rehabilitation Project, Phase 1

Posted on August 20, 2024January 29, 2025 by Kiana Abel

Aerial image of the project pre-rehabilitation. [Elliot Sarnacki]

The Upper Conner Creek Rehabilitation Project is set to mobilize Phase 1 construction early next week. The site is located approximately one river mile downstream from the Dutch Creek Bridge in Junction City. After mobilization, phase 1 rehab will focus primarily on the upstream portion of the area and consists of lowering the riparian floodplain, adding riffle enhancements, placing large wood to slow water and create habitat and planting of riparian vegetation. Crews began mobilizing equipment and staging areas Monday.

The largest feature of this portion is the R1 floodplain. This 5.7 acre broadly lowered surface and pilot channel on river left targets inundation at levels from 500 to 3,500 cfs. Given that this reach of the Trinity’s average winter flow is 771 cfs, this feature should remain wetted for much of the fall winter and spring, providing low velocity salmonid refugia and opportunity for riparian recruitment.

A detailed design of the Phase 1 rehabilitation at Upper Conner Creek provided by the Hoopa Valley Tribe and McBain and Associates.

Supporting this floodplain/pilot channel feature, phase 1 will also see the construction of a riffle (IC-1 ) and the structured log jam (SLJ-1). The riffle (IC-1) is a 160ft long riffle that will raise the water surface elevation to encourage flows onto the new floodplain feature and has the added benefit of providing habitat for benthic macroinvertebrates, which are an important food source for salmonids. In between the main stem Trinity and the new pilot channel is a placed log jam (SLJ-1) which primary purpose is to provide temporary protection to the pilot channel, until riparian vegetation has an opportunity to establish. It is expected that this feature will eventually succumb to the forces of the river, but will provide low velocity salmonid refugia along the channel margins until then. Once revegetation commences this fall, the construction area will receive a compliment of cottonwoods, mixed willows, and a variety of sedges and rushes. The revegetation effort improves the aquatic habitat, helps prevent less desirable plants from taking hold, and generally speeds the healing of the river.

Revegetation design map of the Phase 1 construction area provided by the Hoopa Valley Tribe and McBain and Associates.

Junction City residents should expect to see increased traffic and activity along Red Hill Rd in the vicinity of the Smith Pit. Hours of operation on site are from 7am to 7pm, Monday thru Friday (with an allowance for Saturday if deemed necessary). Civil construction and revegetation of phase 1 should be completed by years end.

If you’d like to read more about the Upper Conner Creek Rehabilitation Project, please click here.

Return to the August Newsletter

Program Update: Implementation Branch

Posted on August 19, 2024April 29, 2025 by Kiana Abel

Large wood placement at Indian Creek a tributary to the Trinity River. [Kiana Abel, TRRP]

The Program has completed the final environmental assessment for the Sediment and Wood Augmentation Along the Trinity River Restoration Reach. It can be located by following this link: U.S. bureau of Reclamation Trinity River… 2024. – at the TRRP DataPort. The project is needed to enhance existing salmonid habitat and provide spawning and rearing habitat in the Trinity River below Lewiston Dam. This will be done by adding suitable-sized sediment and wood through manual augmentation.

Sediment management at the SVEN Olbretson rehabilitation site in the winter of 2024.

The project allows for wood and sediment placement to occur at four new augmentation sites (Dark Gulch, Trinity House Gulch, Steel Bridge, and Vitzthum Gulch) along with the five existing sites (Trinity River Hatchery, Weir Hole/Sven Olbertson, Cableway, Sawmill, and Lowden Ranch). Augmentation below the ordinary high-water mark but above the wetted channel may take place all year. High flow sediment augmentation (also known as injection) will generally take place between April and May when and where it is safe to do so without disrupting juvenile coho salmon. Sediment and wood may be placed directly into the river during the in-channel work period of July 15 to September 15 (or later in coordination with the National Marine Fisheries Service (NMFS) and with best management practices (BMPs) in place).

Each year, at each site, we are allowed to augment up to 8,000 cubic yards of sediment varying in diameter from 0.04 inches to 14 inches. We may also augment up to 700 pieces of wood varying in size from slash to whole trees at a single site per year. Generally, we will augment about 500 to 2,000 cubic yards of 0.375 inch to 5 inch in diameter sediment at a single site per year. The Physical Work Group creates an Augmentation Plan every year, recommending sites for augmentation and quantities of sediment and wood. It is unlikely the Program will augment at more than a few sites per year.

Return to the August Newsletter

John Hayes, Ph.D.

Posted on July 26, 2024January 29, 2025 by Kiana Abel

John Hayes, Ph.D., Freshwater Fisheries Scientist – Cawthron Institute, New Zealand

John Hayes is a freshwater fisheries scientist from Nelson, New Zealand, recently retired from the Cawthron Institute, where he retains an emeritus position. John has special expertise in recreational trout and salmon fisheries, instream habitat modelling and salmonid foraging and bioenergetics modelling. He has led and supervised research and consulting projects on freshwater fisheries, habitat assessment, limiting factors, environmental flow regimes and effects of hydro-power and irrigation schemes.

Over the last two decades of his career John led a series of research projects with New Zealand and USA scientists developing process-based models integrating river hydraulics, invertebrate drift transport and the bioenergetics of drift feeding to predict effects of flow, water temperature and clarity on stream salmonid growth and carrying capacity. Much of his research has been aimed at understanding how rivers work in relation to sustaining fish populations and fisheries to inform environmental effects assessment. He has undertaken fisheries related environmental consulting widely in New Zealand and contributed to a project in Oregon. His salmonid bioenergetics models have been applied in New Zealand, Australia, and the USA – including the North Umpqua and Colorado rivers, and Columbia River tributaries.

John’s interests in fish ecology arose from a life-long passion for fishing. Over his career he has enjoyed communicating freshwater ecology and fisheries science in popular press. He has been a regular writer for Fish & Game New Zealand magazine, also published in Flylife Magazine (Australia), and co-authored the book ‘The Artful Science of Trout Fishing’.

2024 Science Symposium Presentation

Day two of the Trinity River Restoration Program Science Symposium covered Habitat, Flow and Temperature. Listen in as John Hayes, Ph.D., Freshwater Fisheries Scientist – Cawthron Institute, New Zealand presents, “How flow affects aquatic invertebrate habitat and drift, and salmonid net energy intake and instantaneous carrying capacity.”

Eli Asarian

Posted on July 26, 2024January 29, 2025 by Kiana Abel

Eli Asarian, Aquatic Ecologist/Hydrologist, Riverbend Sciences

Eli Asarian is an aquatic ecologist/hydrologist and founder of the Eureka-based consulting firm Riverbend Sciences. He has worked in California and Oregon watersheds for over 20 years. He specializes in statistical analysis of large, complex datasets and has authored or co-authored over 25 technical analyses on flow, water temperature, water quality, and algae.

Since 2015, he has completed seven water temperature studies in the Klamath-Trinity river basin, including “Wildfire smoke cools summer river and stream water temperatures” and the TRRP-funded “Synthesizing 87 years of scientific inquiry into Trinity River water temperatures.” He has assisted with development and implementation of salmon and steelhead recovery plans throughout California, and serves as president of the Salmonid Restoration Federation. Additional info HERE.

2024 Science Symposium Presentation

Day two of the Trinity River Restoration Program Science Symposium covered Habitat, Flow and Temperature. Listen in as Eli Asarian, Aquatic Ecologist/Hydrologist, Riverbend Sciences presents, “Water temperatures in the Klamath-Trinity Basin: flow, other key drivers, and climate change implications.”