Finding Home

By Rosi Dagit, Principal Conservation Biologist, Resource Conservation District of the Santa Monica Mountains

Dear Fish Friends,

I just wanted to provide a short follow up on the conditions of the fish and creeks now that most of the rains are over, and the creeks are settling into a new phase. It has been a crazy three months and the recovery efforts continue. Below is a short essay about the importance of home, not only to those of us whose homes were impacted by the fires, but also to all our fellow creatures, especially the fish, as their homes have been catastrophically changed. We know that eventually the creeks will recover, but the immediate aftermath is intense. Attached are some photos of current conditions in Topanga Creek.

I also wanted to take a moment to say a personal THANK YOU to those who contributed to our fire response efforts. With the $43,000 donations provided to the RCDSMM, we have been to be able to accomplish the following things:

Erosion Control

• Assist state parks with installing erosion control materials by the lagoon which helped stabilize the slopes in the areas where EPA set up their household hazardous waste sorting and lithium battery decommissioning areas.

Water Quality and Topanga Lagoon condition monitoring

• Collect water and sediment samples both up and downstream from the EPA site following each rain event. Sediment samples are being analyzed by researchers at UC Santa Cruz and CSU Long Beach.
• Share water quality and nutrient data with the regional coalition monitoring post-fire water quality impacts.
• Continue monitoring lagoon conditions including breach, sediment deposition and presence/absence seining for aquatic critters.

Rescue southern steelhead

• Conduct the rescue of 271 southern steelhead trout from Topanga Creek in cooperation with CDFW and NMFS.
• Provide appropriate wild food for the trout when they were in the hatchery.
• Assist CDFW and NMFS with releasing the trout into Arroyo Hondo Creek, their new home.
• Check out the video at https://www.youtube.com/watch?v=-R6TBY7jd20

Rescue tidewater gobies

• Conduct the rescue of 760 tidewater gobies from Topanga Lagoon and coordinate with Aquarium of the Pacific and Heal the Bay aquarium to hold them until we can find them a new home.
• Evaluate Santa Monica Canyon lagoon and Zuma lagoon for potential release sites.
• Support the preliminary DNA extraction needed to determine if it will be possible to release them in Zuma with our partners at UCLA.
• Work with USFWS and the aquariums to develop an experimental treatment plan for microsporidia infections.
• Check out the video at https://www.youtube.com/watch?v=m78UPJ5qcIk

Monitor Topanga Creek

• Work with State Parks and Caltrans to protect the creek from road related impacts.
• Assist with protecting trees damaged in the fire and by culvert clearing.
• Photo documentation post rains to document creek conditions.
• Coordinate spring stream surveys, longitudinal stream profiles and other data gathering to establish a baseline for creek condition post fire.

Monitor Malibu Creek below Rindge Dam

• Conduct spring snorkel surveys to check on creek conditions and look for remaining fishes and other species.
• Coordinate a longitudinal profile survey to document post fire habitat conditions as a baseline.

Oak Restoration

• Assess the damage to our oak restoration areas from bulldozers
• Replace damaged cages and prepare replacement planting
• Work with State Parks to identify priority planting and restoration areas

Thanks also to our partners at USC Sea Grant who provided an emergency grant to support the fish rescues and release, and Supervisor Horvath has contributed funds to help cover the costs of the stream mapping.

We have one big task remaining and are looking for an additional $7,000 to cover the costs for our partners at UCLA to do the genetic mapping of gobies from Topanga, Zuma, Ventura and Ormand beach. This will provide understanding of relationships between these populations and is important to know as we consider where to release the gobies.

It will take time for the creeks to recover and become beautiful habitats again. Your RCDSMM will do our best to support the restoration and recovery of these precious resources. Thank you all for your kind thoughts during this difficult time. Together we will continue to work to preserve and protect the Santa Monica Mountains and Bay.

Gratefully, Rosi

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Finding Home

As we all rejoice in the coming of spring and recover from the intensity of the fires, floods, road closures and sediment impacts, I have been reflecting on the importance of “home”, both for humans and fish. Recently, we were able to capture and move over 760 tidewater gobies and 271 southern steelhead trout from Topanga Creek and Lagoon, thanks to your donations. Like the thousands of humans displaced by the fires, our fish are facing a completely new reality. Though we’ve managed to keep them alive, I worry about the swift removal from their homes, and how that affects their long-term recovery. How do these fish compare their home in Topanga Creek and Lagoon to their new reality? Did their abduction by an alien species disorient them? Do they care? Does it matter?

For the gobies, their temporary residence in separate aquariums has had some interesting consequences. They’re eating whatever is provided, and what is provided is much more consistent and nutritious than what they were forced to forage for in the wild. So much so in fact, that they are getting fat and the amount of food being provided is now being cut back. While the all-you-can-eat buffet is a new and different experience, is it a response to the stress of being moved from their lagoon habitat into a tank, albeit a very nice tanks! While we await the information regarding population relatedness (DNA tests also funded thanks to your donations), they are living in a totally foreign environment. How will that impact their ability to recover once we find a wild home for them to return to? And where is their new home going to be?

Topanga Lagoon is full of muddy shallow water and sediment, leaving scant habitat for gobies to live in. During recent monitoring, we found under 25 survivors. As we move into the warm months ahead with little rainfall expected, water levels will continue to decline eventually becoming uninhabitable for fish throughout summer and fall. Where else can they go? Their closest relatives are in Malibu Lagoon, which is also experiencing sedimentation from the Franklin Fire (Dec 2024); though it is, for now, retaining more wetted area. As we work out where to release the gobies, the older individuals are starting to show signs of microsporidia infection. There is no identified treatment for this and so our aquarium partners are hoping to experiment with a few different medications to see what might work. But questions remain. If we put the remaining younger fish into Malibu, would they transfer the infection to that population? What about Zuma Lagoon as an alternative? We confirmed that the tidewater goby population is still abundant there, as of this weekend. Are they closely related enough to mix with this population? What about introducing infection at Zuma? So many questions remain and yet the clock keeps ticking. Additional lab work could be necessary to inform where and when to release them.

The trout by contrast had a much shorter stay in tanks and were introduced into their new watershed on the 10th of February. The Arroyo Hondo watershed lost its trout due to floods following the Alisal Fire (2021) but thanks to two good rain years the habitat is back. We hand carried Topanga trout over a mile into the beautiful pools within the upper watershed. Teams from CDFW, NMFS, Watershed Stewards Program and Land Trust got a big workout that day! The Land Trust of Santa Barbara County opens the area for visitors on the first and third Saturdays of the month. Reservations are required but if you are looking for a fun weekend outing, hiking in to check on the creek could be fun. I am hoping to get there in May. Stay tuned for updates.

All the trout were put into a single tank for transport and we had no way of keeping track of which fish had lived together in their Topanga pools so they were randomly grouped when moved. During our ten year mark-recapture project, we learned that, during the drought years especially, individuals remained in the same 1-2,000 meter reach of the creek, and often in the exact same pool for years, associating with the same group of individuals throughout that time. They knew all the nooks and crannies in that part of the creek – could hide, feed and mate with others they knew. What happens when we move them into a totally new environment, with a random group of unfamiliar fish? What does it take for a fish to make a new place home? Will they reproduce and thrive? We certainly hope so and early reconnaissance suggests that they are settling in. But it will take time and monitoring to really understand the impacts of this massive shift.

Three months post fire we humans are still unsettled and disoriented, trying to navigate all the changes, big and small. The magnitude of this disaster continues to alter our sense of place, our sense of home. Like the gobies and trout, we need to find the places that support us. Thanks to all of you, we have had resources needed to at least try and support survival of these fish.