Angelo Reserve Participates in Berkeley’s Big Give

Berkeley Donations 2016As part of the University of California, Berkeley, Angelo Reserve is participating in the Big Give.  We are encouraging you to make a donate (tiny, small, medium, yuge) – of any size to help contribute to continuing world class research in our natural areas.  

What is it?
Big Give is an online fundraising event taking place during Big Game week, giving you and the entire Cal community — alumni, parents, students, faculty, staff, and friends — the chance to come together to support your favorite schools and programs, and help those schools and programs win prize money. This is our third annual Big Give event.

When is it?
9 p.m. PST on Wednesday, November 16 to 9 p.m. PST on Thursday, November 17, 2016.

Partnership of ERRP and Angelo ERCZO in monitoring cyanobacteria blooms

I wanted to draw attention to the commendation of the Humboldt Count Board of Supervisors commendation of the partnership of the Eel River Recovery Project and UC Berkeley’s Angelo Reserve (mainly the efforts of Keith Bouma Gregson) in drawing together residents and researchers to locate and watch toxic cyanobacteria, and investigate the environmental changes that may be supporting more frequent, expansive, or problematic blooms of these potentially toxic ‘bluegreen algae’.  Pat Higgins, Managing Director of ERRP, is quoted as saying “UC …kind of adopted us and said ‘We want to come and do algae studies on the Eel and use your volunteers’….”  but we Angelinos feel the other way around, very grateful for all that we are learning from the ERRP volunteers about the history and current environmental trends in the larger Eel River basin.  It isn’t that common that academic field biologists find such amazing partners and friends when trying to work on larger scale environmental problems–many, many thanks to ERRP for their partnership, energy, organization, field skills, and deep commitment to the future of the Eel.

Keith and rescue dog folks

Keith Bouma Gregson and Jan Friedrichsen from the California Rescue Dog Association, determining whether dogs would be safe working in this area of the Eel River. photo by Pat Higgins.

see Daniel Mintz, 2015.  County commends Eel River algae monitoring partnership.  The Independent (Southern Humboldt), Tuesday July 28, 2015, pp. 1-3.Hum_Supes_ERRP_UC_CZO_Resolution

Listening to the forest breathe: monitoring tree trunk sap flow and size

Water is a polar molecule, a property that accounts for many of its unique physical properties

Water is a polar molecule, a property that accounts for many of its unique physical properties. Photo credit: Jesse Hahm

Trees must pull water from soil and rock, where it is held at tension, to their leaves, where it evaporates to the atmosphere through open stomata. This process, called transpiration, is a major component of the hillslope water budget and can dramatically affect the local climate by lowering air temperature and increasing water vapor concentrations. Understanding how trees use water is a major topic of research at the Angelo Coast Range Reserve. How does the seasonality of transpiration differ between species? At what water content (and potential, or tension) in the subsurface do trees become so stressed that they close their stomata to prevent embolisms (damage to their vascular tissues)? How does rock type influence how hard trees must pull to extract water from the vadose (unsaturated) zone? How do trees access water to continue to transpire throughout the summer drought in Mediterranean climates?

When does this Douglas Fir become water-stressed?

When does this Douglas Fir become water-stressed? Photo credit: Jesse Hahm

To answer these questions, researchers are monitoring tree physiological response to environmental conditions in the Angelo Coast Range Reserve. Sapflow (the vertical ascent of water through xylem) can be measured using a simple sensor consisting of three prongs placed into the sapwood of the tree. The central prong emits a heat pulse, and the two surrounding prongs sense changes in temperature. Flowing sap advects the heat pulse so that a temperature rise is sensed sooner in the upper temperature probe. This principle enables the sapflow velocity to be determined.

Bark must be scraped away to place sensors into the sapwood. The fleshy red bark is characteristic of tan oaks.

Bark must be scraped away to place sensors into the sapwood. This fleshy red bark is characteristic of tan oaks. Photo credit: Jesse Hahm

Sapflow sensors have three metal prongs aligned parallel to the flow of sap. The central prong emits a heat pulse every half hour.

Sapflow sensors have three metal prongs aligned parallel to the flow of sap. The central prong emits a heat pulse every half hour. Photo credit: Jesse Hahm

As the tree ‘pulls’ water up from below, tension increases in the water column in the xylem. This suction can influence the size of the tree trunk, which can be measured with very precise piston dendrometers. These sensors capture the diurnal size variation due to changes in both water content and potential as well as tree growth.

This piston dendrometer senses changes in trunk radius with micrometer-scale precision.

This piston dendrometer senses changes in trunk radius with micrometer-scale precision. Threaded bolts are sunk into the heartwood of the tree to provide a stable reference frame. Photo credit: Jesse Hahm

Eyes on the Eel!


Some evening in June, July, or September, you may see a wet, tired crew of river ecologists eating burgers at The Peg Inn (Never don’t stop there!) or the Chimney Tree House in southern Humboldt.  Or you may see our EoE tags along the river–The “Eyes on the Eel” is an ongoing survey of the state of river and tributary ecosystems along Eel mainstems and tributaries, one of four long term research tasks outlined for the Eel River Critical Zone Observatory.  Led by Profs Stephanie Carlson and Mary Power, and graduate students Suzanne Kelson, Gabe Rossi, Phil Georgakakos, and Keith Bouma-Gregson, our Berkeley-based student crews have been, frankly, amazing at putting up with long days, hard work, wet clothes, while steadfastly documenting physical conditions, cyanobacterial and algal abundances, invertebrates, and vertebrates along 48 transects and 16 pool-riffle units in four tributaries and four mainstem sites down the South Fork and mainstem Eel River.  We thank these student researchers, and to the  generous land owners who have given us permission to visit their property for one day per month for our surveys.  We will be working to publicize our observations in ways that will be widely accessible and informative, and, we hope, will invite collaboration and comparisons with observations of others along the Eel.  For example, Eyes on the Eel, in some ways, complements the extensive snorkeling surveys of deep pool habitats performed by the Eel River Recovery Project.  The rationale and methods for this effort are described in more detail under the Research section.

September 2015 Eyes on the Eel Crew in Wilderness Lodge meadow

Angelo and Eel River CZO on local radio

We were very pleased and grateful for an audio report from Berkeley undergrad Sohil story about his experience at the Angelo this summer.  His grad student mentor Suzanne Kelson reports “His story was chosen by the local radio station (KOZT the coast, “I love this town”) and played Thursday, August 13. Very cool! I’m proud of Sohil”
Here’s the link to listen to the story:

Keith Bouma Gregson and Mary Power have both chatted about cyanobacteria, drought, and other river issues with Patrick Higgins, Executive Director of the Eel River Recovery Project, on KMUD’s Monday Morning Magazine., e.g.,  June 1 2015.

Jerry Schubel, Director of the Aquarium of the Pacific in Long Beach California, hosts Coastal Conversations, a monthly program that deals with major issues confronting the nation’s coastal areas—marine and in the Great Lakes.  He was the lead author of a July 2014 of the National Academy of Science National Research Council entitled “Enhancing the Value and Sustainability of Field Stations and Marine Laboratories in the 21st Century”.  On Feb 27, Jerry invited three authors of that report, Felicia Coleman from Florida State University’s Coastal and Marine Laboratory, Rob Plowes, from the University of Texas, Brackenridge Field Laboratory, Mary Power, from the University of California, Berkeley, Angelo Coast Range Reserve, and Peter Kareiva from The Nature Conservancy, to discuss the importance of natural history field stations for research, education, and outreach, and ways of increasing their impact and viability  into the 21st century. 

Climate extremes and the Critical Zone

As people who had planned to live ordinary lives face early-onset climate change, we are discovering that it not the change in average temperature or precipitation, but the extremes that will change our future. In the US alone, we are already seeing parched landscapes throughout western North America, while deluges and storm surges destroy crops and infrastructure throughout the Midwest and the East coast. Droughts and heat shocks, or deluge and super-storms, are following atmospheric and ocean warming, because, as Gregory Johnson’s haiku version of the IPCC 2014 report states,

“Wet will get wetter/and dry drier, since warm air/ carries more water.”(

By now, we have little ability to correct the atmospheric and ocean conditions that have triggered weird, often violent weather around the globe (although we should rapidly change our energy sources to avoid making it worse).   Instead, we must turn our attention to the skin of the Earth, where life meets rock, and cycling water is received, stored, transformed, and released back to the atmosphere, or as runoff to surface waters. We call this Earth skin the Critical Zone. It extends from the top of the vegetation to weathered bedrock deep beneath our feet. The lower part of the Critical Zone is largely unobserved, but of crucial importance. It begins where fractures in bedrock give plants and microbes access to stored water, and provide flow paths feeding the springs, rivers, wetlands, lakes, and estuaries on which most terrestrial life depends. Careful stewardship of Critical Zones—the vegetation and the soil and bedrock beneathe–could help us buffer, and even ameliorate, temperature and precipitation extremes at local, regional, and, perhaps some day, global scales. But to steward something, anything, it must be understood. That is the purpose of the network of Critical Zone Observatories, funded by the US National Science Foundation.

See the Research section of this web site for reports from studies at the Eel River Critical Zone that 1) explain how uplift and drainage affect the ability of bedrock underlying Coast Range hillslopes to store and slowly release the water that keeps springs, streams and rivers flowing during drought (Rempe and Dietrich 2014); and 2) predict that temperatures in our wooded landscapes would be elevated 1-2oC if we replaced all the broad-leafed trees with conifers (Link et al. in preparation).

Turbidites and rip-up clasts in Elder Creek

Elder Creek, part of the South Fork Eel River watershed, lies in the Franciscan Formation found underfoot in most of the Northern Coast Ranges of California. The rocks here were deposited in marine environments when the Farallon slab was still subducting under the North American plate at this latitude. Subsequent uplift following the passage of the Mendocino Triple Junction has elevated these rocks out of the sea.

Clastic sedimentary rocks found in Elder Creek record information about their depositional setting. Grain size, lithology, and shape all provide clues about the energy of the flow and the time spent in transit, sorting and abrading. The vast majority of the rocks in Elder Creek are turbidites, formed from turbidity currents: dense slurries of sediment sloughing off the edge of the continent, rushing off the continental slope to final resting places in deeper, still waters. These currents are thought to be triggered by earthquakes, among other things.

Turbidites contain sand and pebbles that were rounded in terrestrial rivers prior to their arrival at the ocean. They also contain small clay-sized particles that fall out of the ocean water column (the long snowfall, in Rachel Carson’s words). As numerous currents are laid down over time, they create a rhythmic sequence of grain sizes, with a fining upward sequence recording stratigraphic ‘up’ (left to right in the image from the bed of Elder Creek below.)


Rhythmically bedded turbidite sequence (pebble to sand to clay size), Elder Creek. Photo credit: Jesse Hahm

Sometimes turbidity currents race over clay-sized mud deposits (shale). They pick up bits of the semi-lithified shale and carry them along. These shale bits are called rip-up clasts or intra-formational clasts. They are recognized by their darker color and angular shape, and are often much larger than the terrigenous sediment that surrounds them.

Rip-up (intra-formational) shale clasts in sandy matrix, Elder Creek

Rip-up (intra-formational) shale clasts in sandy matrix, Elder Creek. Photo credit: Jesse Hahm

Measuring stream discharge with the salt dilution technique

Measuring water fluxes in the Eel River Watershed is extremely important. We are in the midst of a multi-year drought and demands on the water supply for agriculture and rural use are only increasing.

An ongoing project at the Eel River Critical Zone Observatory is to improve existing stage-discharge relationships, to better document the amount of water flowing through the watershed. Stage refers to the height of water in the river, and discharge refers to the volume of water that flows by in a given time.

We can measure the stage with an automated system that makes use of pressure transducers, but knowing the discharge is complicated because of the ever-changing geometry of the river bed and the turbulent nature of flowing water. The approach to this problem is to develop an empirical relationship between stage and discharge across a range of stages, from low summer baseflow to high winter floods.


Salt dilution technique by David Dralle

Salt dilution technique by David Dralle

Here David Dralle is demonstrating the salt dilution technique to measure discharge on the South Fork of the Eel River, just downstream from Headquarters. A known volume of salt solution is added to a turbulent stretch of the river, and the increase in electrical conductivity is measured downstream, after the salt is well mixed into the flow. The more the salt is diluted, the higher the flow.

Dan Moore has written a very helpful series of articles on the use of the technique. For more information, see the intro to the series, published in Streamline Water Management Bulletin (

Phil G encounters invaders in Hunter’s Pool, just downstream from Angelo


Invasive red swamp crayfish.  Photo by Phil Georgakakos.

Phil Georgakakos sent these photos yesterday of two invaders–the red swamp crayfish, Procambarus clarkii, and bullheads tentatively identified by Mary Power as black bullheads, Ictalurus melas.  (It may be a brown bullhead, check out the pectoral spine-if smooth, black, if barbed, brown bullhead, I. nebulosus).  Phil and I had seen red swamp crayfish in S.Fk. Eel just below its confluence with Ten Mile Creek near Laytonville last March (see previous post), and Sarah Kupferberg and I have found them upstream within the reserve later, but all the individuals we saw were dead.  Phil yesterday found the first live specimen–a male (see the claspers where its belly button would be, were it a placental mammal…).


Baby Bullhead. Photo by Phil Georgakakos


Photo by Phil Georgakakos

While we are concerned about these invaders harming native species in the Eel, I have to mention how cool bullheads are.  These catfish know each other individually through chemical recognition–fish respond very differently when “enemy” vs “friend” water is poured into their aquarium (google John Todd’s article in Scientific American).


Bullhead family. Photo by Phil Georgakakos.

Mother and Dad take care of the fry (the little black guys with adorable mustaches in Phil’s photo, above.), marching them around pool bottoms in little swarms as they learn to feed.   But what are they feeding on?  Bill Dietrich was just wondering if they, among other reasons, may be why we no longer see little native freshwater mussels, and are so worried about their failure to recruit in rivers along the North Coast…bullheads suck up their food from the substrate, and this might include newly settled mussels in depositional pool habitats…