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Arroyo Seco Foundation

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Arroyo Seco Foundation Talks Bringing Trout, Other Native Fish Back to Pasadena





<b>July 12, 2010</b> - Fish, like Rainbow Trout and even the majestic steelhead, used to be an important part of the Arroyo Seco. Tonight the Arroyo Seco Foundation will host a meeting to discuss the past, present and future of fish in the Arroyo Seco. Don't miss it.


Brandon Villalovos


Pasadena New


When Gaspar de Portola visited the Pasadena area in the late summer and fall of 1770, he explored a wide, shallow canyon he decided to call the Arroyo Seco because it had such little water flowing through it. The water it did have, in a creek, contained numbers of fish.

Over time, human intervention in the Arroyo has radically changed its ecosystem. The creek is gone. The fish, too.

Tonight, naturalists and scientists will gather to discuss what they say is the very real possibility of bringing back the fish when The Arroyo Seco Foundation hosts “Native Fish in the Arroyo: Can We Bring Them Back?” at 7 p.m. in the Donald Wright Auditorium of the Pasadena Public Library main branch.

“I don’t think very many people have been thinking about fish in the Arroyo for quite a long time, but it used to be a main feature of the Arroyo Seco and we’d really like to bring back native trout right into the middle of Pasadena — and we think it is possible,” explained The Arroyo Seco Foundation Executive Director Tim Brick.

The Arroyo Seco is a tributary of the Los Angeles River and historically supported a thriving native fish population which included an ocean-going species of rainbow trout called the Southern California Steelhead.

Steelhead are a unique form of rainbow trout. Like salmon, they spent most of their adult lives in the ocean, but spawn in freshwater streams and rivers.

After the construction of Devil’s Gate Dam in 1920, steelhead could no longer reach the cold waters of the upper mountain watershed of the Arroyo Seco to spawn. The concrete channels replacing the Arroyo Seco stream and the Los Angeles River the journey impossible.

Now there is a growing effort, led by the Arroyo Seco Foundation and other participants including Stillwater Sciences, to plan, prioritize, and implement projects that protect and restore the native stream habitat and pave the way for the reintroduction of native fish in Pasadena.

“Those are really the things that knocked out most of the fish in the Arroyo. We think it’s time to take a new look at how to manage those facilities and to do what we can to try to restore conditions that are a good habitat for fish,” said Brick.

According to AJ Keith, Senior Aquatic Ecologist at Stillwater Sciences, the upper watershed of the Arroyo Seco has been relatively unaffected by human development and is potentially capable of supporting native fish, primarily native rainbow trout.

That watershed includes the Arroyo Seco and smaller tributaries in the San Gabriel mountains upstream of Hahamongna Watershed Park near Jet Propulsion Laboratory.

Trout have historically been present in that area, but the extent of their population in the upper watershed is currently unknown, especially since the damaging effects of the 2009 Station Fire, according to Keith.

“Bringing back native fish initially will require moving a small number from a healthy population that currently exists elsewhere. If favorable habitat conditions are present, fish populations could conceivably reproduce and grow on their own and potentially populate other nearby habitat as it is restored,” explained Keith. He has more than 20 years of experience in aquatic and terrestrial ecology.

This type of relocation of native fish in the Arroyo in Pasadena is not the first attempt by ecologists.

A previous habitat restoration project took place in 2007 near the Brookside Golf Course and relocated native Arroyo chub to a restored habitat with varied results.

“It is unclear whether any of these translocated Arroyo chub remain and there are ongoing challenges, such as sediment from upstream and lack of suitable upstream and downstream habitat, that continue to make it a challenging environment for native fish,” explained Keith.

Existing “soft-bottom” habitat is the initial target for restoration and removal and restoration of the channelized and concrete-lined stream channel is among the plans for restoration, according to Keith, who says that he majority of the lower Arroyo Seco downstream of Devil’s Gate Dam no longer provides suitable habitat for any aquatic species.

Some believe a population of trout exists at higher elevations above Pasadena.

“We think there are native trout up in the mountains. They’re probably high up in elevations around four thousand feet,” explained Brick.

The Arroyo Seco Foundation along with Stillwater Sciences, the U.S. Forest Service, and the California Department of Fish and Wildlife see the restoration process as something that can be done and within a reasonable amount of time.

“There’s no reason that there can’t be a naturalized stream basically through all of Pasadena,” said Brick. “I think we can see some real changes in the Arroyo in five years and very substantial changes probably within ten to twenty years,” Brick added.

The public is invited to learn about the the Arroyo Seco Foundation’s plans to repopulate native fish in the city’s watershed areas at a meeting Wednesday at 7:00 p.m. at the Donald Wright Auditorium located at 285 E. Walnut St.

The discussion will feature presentations by Wendy Katagi and AJ Keith from Sillwater Sciences and by author Tom Tomlinson, who wrote the book,”Against the Currents”, which tells the story of the majestic steelhead that used to travel up and down the Arroyo Seco.

To get involved in fish restoration, contact John Goraj at

For more information, visit




Arroyo Seco Foundation, PO Box 91622, Pasadena, CA 91109-1622 (323) 405-7326