The trout are back! After a long dry spell recent rains have created excellent conditions for trout recovery. We want to document the presence of native Rainbow Trout in the Arroyo Seco. It will build a good case for improving stream and habitat conditions in the Arroyo Seco, a key tributary of the Los Angeles River.
We would like to enlist some enthusiastic scouts to search the upper reaches of the Arroyo Seco stream to find native trout there. The upper stream is accessible from trails off of Angeles Crest Highway. ASF can provide information about likely sites and proper procedures.
This will be a very signifcant and exciting project for fishers and Arroyo lovers to participate in. If you are interested or want to report a sighting, please send a message to firstname.lastname@example.org.
According to KCET, National Park Service researchers have installed a series wildlife cameras across 30 miles of the river’s course to try and get answers on how foxes, bobcats, opossums, coyotes, skunks, raccoons and other mammals use the area.
Around 30 cameras have been installed this year, from relatively wild areas in Griffith Park to little strips of property right outside of downtown L.A. that could be as small as 10×20 feet. The program will hopefully help determine whether the LA River acts as a wildlife corridor between the more than 150,000-acre Santa Monica Mountains National Recreation Area and spaces in the city.
By Tim Brick
Arroyo Seco Foundation
It’s time to head to the upper watershed in search of native trout. It has been another disappointingly dry year, but there is water in the stream, and some chance of spotting native fish. The flow in the upper Arroyo stream is now about 2 cubic feet per second, compared to the historic average of 5-6 cfs for this time of year, but 2 cfs is better than it’s been for a while.
WHERE TO LOOK: The most likely place to find native trout would be in the pools up around Switzer’s Falls and in nearby Bear Canyon, but trout sometimes go as far as the mouth of the Arroyo near Jet Propulsion Laboratory. (Btw, the Mount Wilson Bicycling Association has been doing monthly trail restoration work in the stretch of the Gabrielino Trail between Oakwilde and Switzer’s Camp.)
No one that I know of has claimed to see any native trout since the Station Fire nine years ago. I recently went with Wendy Katagi of Stillwater Sciences to visit the Riverside Corona Resource Conservation District, which has an excellent native fish program. They are willing to help us restore native fish in the Arroyo Seco, but first we need to document their current status, so we need your help now.
Take a hike! It’s always enjoyable in the upper Arroyo, particularly this time of year. Let me know what you find, and thanks for caring!
I wanted to give you a quick update on the initial “trout scout” that Arroyo Seco Foundation and volunteers did last week at Switzer’s Falls on Feb. 11. Please keep in mind that this first trip was not meant to be a technical, scientific survey, but rather to get a general idea of the habitat conditions for native trout and stream ecology/hydrology at the moment. But, the next few trips will become more technical as time goes on, employing GIS, DNA extraction and using snorkeling and wetsuit gear to look for trout.
We walked about two miles down the trail, stopping several times along the way to survey conditions and look for evidence of life. One thing is for certain — the Arroyo Seco has not flowed this turbulently in several years! I would guess that the streamflow was close to 50-75 cubic feet per second. It was so wonderful to see. We had to jump over the stream on rocks and downed logs several times along the way. There were several three-to-four-foot-deep pools as we made our way through the canyon. Many of these pools possessed some critical habitat features needed for rainbow trout: clean gravel beds; in-stream woody debris and boulders that create additional pools, turbulent, cool water and overhanging vegetation creating cover. Additionally, the strong root systems of white alder and cottonwood trees that line the stream have established solid banks, which is another key component of healthy mountain streams needed to sustain trout species.
Although we did not see any fish this time, the most salient observation I can make right now is that I do believe some trout are living up there. All or most of the necessary habitat conditions are present and I think it’s only a matter of time before we see some fish.
The next survey will focus on going deeper into the Bear Canyon area. I have heard from several anglers that they have seen trout up here prior to the 2009 Station Fire. The combined effects of the fire and the recent five-year drought had made seeing trout in this area improbable. But I don’t think this is case anymore. The Switzer Falls/Bear Canyon area is recovering quickly and now with all the rain and snowmelt, conditions have changed for the better.
Thank you for your interest as always and feel free to email me with any questions or comments at: email@example.com.
On our return to Sepulveda Basin, to continue the upper river fish survey, we captured 203 fish, a far cry from the more than 3,600 tilapia fry caught this time last year.
There had been the first major rain of the season the day before, on Monday, Nov. 21, with between 0.75-1.25 inches over the LA River basin. Sediment and the remains of several homeless encampments were in our car park site. Muck was unconsolidated and varied from 1-6 inches deep. We couldn’t walk far upstream, starting 30 yards to the underpass at Burbank Blvd. because the water was too deep but flow in the main stem concrete area where the sample sites are located was shallow. Most of the vegetation along the banks was gone with just a few patches of water primrose (Ludwigia hexapetala), a few cattails and some willows closer to the bridge were all that remained.
The majority of fish were non-native juvenile Tilapia sp. and Gambusia affinis. Both of these species are common and abundant throughout the LA River, where they were initially released to control mosquito larvae. Samples of both species, as well as fathead minnow, juvenile red swamp crayfish and Asiatic clams were also collected and frozen for toxicology testing.
A single adult Plecostomus (Hypostomus plecostomus), which is a common aquarium fish, was also found washed up on the concrete bank at site 2. It recovered when placed into cool water, but was collected for toxicology testing.
An Army Corps ‘dozer and dump truck moved sediment and debris out of the concrete channel, according to their management permit. The site supervisor kindly allowed us to complete our site 1 and 2 sampling before they moved heavy equipment into that area. The rest of our six sites were upstream of their work area.
Following collection of what looked like an arroyo chub (but was later confirmed to be a fathead minnow) at site 1, just downstream of the disturbance in the channel, we contacted the California Department of Fish and Game about this potential threat to any other arroyo chub that might have washed down.
Dagit is the Senior Conservation Biologist, Resource Conservation District of the Santa Monica Mountains.
8 a.m., arrive at meeting site – The park gate on Burbank Boulevard, just west of Woodley Avenue. This is the kayak loading site and it’s roughly a quarter-mile upstream from Sepulveda Dam.
8:30 a.m., William Preston Bowling will greet everyone with liability waivers. Volunteers signed in, put on waders/sunscreen, and took the fishing gear and buckets down to the river at site 1 and Anglers bring their own gear and valid fishing license.
We are collecting fish to observe and throw back, showing all your catch to biologists once caught, they will decide what species to keep for toxicity study.
This will be the second outing of the third “Los Angeles River Fish Studies” created by FoLAR. This study is in Partnership with Stillwater Sciences and the Resource Conservation District of the Santa Monica Mountains.