Guest Posts

A Boat-side View of Restoring South Bay Tidal Marshes

admin — Wed, 16 Aug 2023 16:53:07 +0000

A Boat-side View of Restoring South Bay Tidal Marshes admin Wed, 08/16/2023 - 09:53

It’s time for another guest post! We are lucky to get a boater’s-eye view of our restoring tidal marshes from Jim Ervin, who writes a monthly nature blog for UC Davis, a summary of eyewitness observations from the boat used by UC Davis fish scientists as they cruise up and down the Coyote Creek and around Alviso marshes and sloughs trawling to monitor fish. Jim takes the photos and develops maps to track the outcomes of the university’s fish monitoring crew.

First, some background:

The UC Davis Otolith Geochemistry and Fish Ecology Lab has been conducting fish monitoring surveys of Lower South San Francisco Bay since 2010. Most of this monthly work is conducted in and near several of the restored former salt ponds along the lower segment of Coyote Creek and surrounding marshes. We count roughly 60 species of fish and bugs (invertebrates) at 20 stations every month. The main purpose of this work is to monitor a small but growing resident population of a threatened fish, Longfin Smelt. But, we also track the overall health of the marsh and long-term ecological changes.

Long story short…I have been taking pictures of the pond restoration process along Coyote Creek since about 2012. However, because the UC Davis blog is a fish blog, I only occasionally post photos of marsh growth.

I am very interested in the plants, but my knowledge is rudimentary at best. This is a brief overview of almost ten years of observations in restored former industrial salt Pond A19.

Map of rough location of my photos by boat of Pond A19, opened to the Bay in 2006 to regrow tidal marsh.

Pond A19 - the first few years

Pond A19, shown in these photos, is a 265-acre area along the Coyote Creek delta near Milpitas that the Restoration Project breached for passive restoration in March 2006. I started photographing in earnest around 2014 when the interior of the pond was still mainly naked mudflat.

In 2014, eight years after it was breached, soft mud had accumulated, attracting foraging egrets and other birds.

It has been interesting to watch the restored ponds gradually fill in with sediment and start to bloom. But, it takes patience: seasons changed, years passed, the marsh slowly accreted.

Summer 2014: Isolated patches of cordgrass sprang up in summer, but died back to rhizomes each winter.

We first noticed substantial patches of spartina (cordgrass) starting to fill in around 2016. But progress was intermittent. Cordgrass grew tall in summer when Bay water was salty. It would then get knocked flat the following winter when rainwater flushing made water fresh again. But, very slowly, Pond A19 continued filling in.

Two years later, more substantial patches of cordgrass had started to fill in.

The Freshwater Flush of February 2017

A big change happened in 2017. I call it “a watershed event.” That was the year of the February Freshwater Flush. If you live in this area, you may recall that exceptionally heavy rains fell in San Francisco Bay that winter. It caused substantial flooding in San Jose and some other places.
The flooding had a profound impact on these marshes. For a few months, the local rivers were swollen with fresh water. Salinity dropped almost as low as tap water for a few months, causing a minor die-off of sharks and rays that were caught too far upstream.

Low salinity also encouraged the recruitment of many small fishes and bugs. Our counts of baby gobies and longfin smelt quickly rose to numbers we had not seen before.

Heavy 2017 rains flooded San Jose and other areas. All the fresh water produced large numbers of bugs and small fish.

Within a few months, we could see that populations of several desirable fish and shrimp species had increased both in Pond A19 and in the surrounding area. At the time, we could not know if this was a permanent change or just a fluke.

We sensed but did not fully appreciate the extent that Pond A19 was becoming an important spawning and rearing habitat for fishes and the tiny bugs they eat.

But, I digress…

More years pass. The pond restores.

By next year’s summer, cordgrass had spread like wildfire. Each summer, I felt, the pond became a marsh paradise.

The above-ground picture was equally compelling – but, only in the summer. Cordgrass was spreading like wildfire across the former mudflat. Every summer, I felt that Pond A19 had turned into a marsh paradise.

But then, often as not, winter coldness and freshwater flushing would knock the cordgrass back down to mudflat and rhizomes. This was a little depressing from a marsh plant point of view.

Nonetheless, underwater productivity continued to improve, with greater numbers of mysid shrimp.

February 2019: winter cold and rains knocked down plants to rhizomes. Underwater, productivity improved - we counted more small fish and bugs.

The good news was that we were seeing solid signs that cordgrass, pickleweed, and California bulrush were reemerging more widely and rapidly each spring.

These marsh plants establish rhizomes that survive through tough times. Marsh plant diversity was also increasing.

Map of rough location of my photos by boat of Pond A19, opened to the Bay in 2006 to regrow tidal marsh.

Is it Restoration Success yet???

It has been a bumpy ride. At Pond A19, overall, vegetation restoration progress has been slow but steady. Fish production is up. The tiny bug production is definitely feeding our fish production, and we counted many spawning anchovies.

Now, even in drought, the marsh continues to expand each summer. Cordgrass and pickleweed abound; fish and bug production seems to be up.

Sediment accretion has been slow at this pond area compared to Pond A21 just downstream, but hopefully, some hydrology improvements the Restoration Project added to Pond A19 in December 2021, opening up and flattening more levees, will speed that up.

To my mind, the fish-killing red tide that struck San Francisco Bay in July through August 2022 was a major unplanned “stress test” of restoration success.

The natural ecosystem, from microscopic bugs to tiny fishes, tends to buffer against big upsets such as those that were experienced farther north in San Francisco Bay last summer. However, this is difficult to prove or quantify. Fish died up there, but they didn’t die here in the same bay under almost identical conditions. We must understand this!

Seasons always change. Once again, we saw robust marsh plant growth in summer through fall 2022.

Marsh plant growth was bigger and more widespread than ever in summer through fall 2022.

But, as in all previous years, plant growth died back considerably after yet another big freshwater flush from multiple atmospheric rivers in late 2022 through early 2023.

March 2023: the deluge of early 2023 atmospheric rivers knocked marsh plants back down to rhizomes once again!

The marsh plants will grow back later this spring. They must!

June 2023: Lush plant growth has returned!

Note: Jim shares further observations about Bay plants, including the greenery resulting from our very wet 2022-23 winter, in a recent post on his UC Davis Fish in the Bay blog, Special Report: Marsh Plants in the restored Garden of Eden. He will periodically provide us updates on his observations.

Jim Ervin

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A New Technique to Scale Up Our Revegetation Efforts

ariela — Wed, 15 Jun 2022 23:26:56 +0000

A New Technique to Scale Up Our Revegetation Efforts ariela Wed, 06/15/2022 - 16:26

In my most recent blog post, I wrote about what habitat transition zones are, why these slopes rising from tidal marsh are important parts of our Restoration Project, and introduced Save The Bay’s vital role in making them ecologically rich areas of native plants that make more complete and complex marshes. This time around, guest blogger Jessie Olson, Habitat Restoration Director of Save The Bay, will dig into the details and share more of how they have done their work at our Ravenswood ponds. Take it away, Jessie!

Save The Bay has a history of successful restoration efforts that take a community-based approach to revegetation. These student and volunteer programs can spark a lifelong love of shoreline open space by giving community members an opportunity to participate in hands-on restoration. These programs also encourage participants to invest in the protection of tidal marsh and related habitats by voting for elected leaders and policies that prioritize the health of the Bay. Until recently, our projects have been small scale and implemented over long periods of time.

But now, to meet the urgency of sea level rise and climate change, we need to restore more acres of habitat transition zone and marsh-edge habitats more quickly. To do so, we realized that we needed to think beyond what our staff and volunteers were capable of hand-planting in a season. To broadly revegetate larger sites, we needed methods that would reduce the cost and labor associated with the process. This is where the idea of “farming” native plants came in – and the South Bay Salt Pond Restoration Project’s recently built habitat transition zone between Ravenswood Pond R4 and the City of Menlo Park’s Bedwell Bayfront Park (“the Pond R4 habitat slope”) was the perfect site to test it out.

Borrowing from concepts used not only by farmers but also by indigenous tribes, Save The Bay and ecological consultant Peter Baye planned to grow native broad-leaf and grass species that were historically common on the edges of San Francisco Bay. These are resilient species with the ability to form dense, drought-tolerant sod that, once well-established, is nearly impenetrable to the colonization of invasive annual species.

To grow large numbers of plants to place on the 10-acre R4 habitat slope, Save The Bay built a raised-bed nursery close to the site on a parcel of land owned by the West Bay Sanitary District, which allowed us to use that space at no cost. We constructed 82 raised beds, similar to what you might build to grow vegetables or herbs in at home. We then filled these beds with native, perennial species collected from South Bay populations as close to the restoration site as possible.

In fall 2021, prior to the rain, our habitat restoration team began to harvest the nursery's native plants and break up the sod so it was ready to be mixed in by a farming contractor. The process of digging the sod pieces out of the beds was both time- and labor-intensive but produced massive amounts of propagules (clippings or cuttings that will regrow when planted) – multitudes more than what is possible with traditional container plants. After we delivered the sod pieces to the planting site, Frank Imhof, a local farmer, used a tractor with a special attachment to mix the plant material into the soil of the R4 habitat slope. We followed that by hand-spreading a native, annual seed mix. Then we planted additional species throughout the slope to add diversity and functionality.

With increasing drought, a global pandemic, and project delays, the work of habitat restoration is a constant challenge and test of our flexibility and patience. After growing plants in the beds for a few years, we moved and replanted tens of thousands of propagules between November 2021 and March 2022.

What is remarkable is that our early monitoring indicates that these experimental “farming” methods are effective. Now, much of the plant material, from sod to annual seeds, is established on the site and producing healthy vegetative growth. We intend to replicate these techniques next fall at our second Ravenswood planting site. We hope that what we’ve learned can inform restoration practitioners elsewhere.

Our role at Save The Bay is to distill the incredible science done by our partners, like the South Bay Salt Pond Restoration Project, into exciting and educational communication with which we may empower our community to take the protection and stewardship of tidal marsh and adjacent habitats into their own hands. We hope that hand-planting a native species into a habitat transition zone is the first step toward lifelong advocacy for the remarkable place we call home.

In the coming year, we will need help from volunteers to remove invasive plants and maintain the planted slope. After a long COVID-related hiatus, we plan to reintroduce our popular public programs this summer and welcome volunteers back to the shoreline. We’d love to see you there! Learn more about our volunteer opportunities here.

Farmer Frank Imhof plants natives. Credit: Save The Bay

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A Simpatico Science Symposium

ariela — Wed, 27 Apr 2022 18:29:21 +0000

A Simpatico Science Symposium ariela Wed, 04/27/2022 - 11:29

Hi Everyone! Donna Ball, Project Lead Scientist here. Dave is out in the field taking pictures of heavy machinery moving massive amounts of dirt (you’ve seen the pictures in his prior posts) or some such activity. While he’s away, I thought that I would hijack his blog to tell you about the upcoming Science Symposium. So, pull up a chair…

What’s a Science Symposium, you might ask. Well, it’s a gathering of scientists and managers all in one place (virtually – at least this year) at one time to share and discuss the science that is happening on the project.

The Symposium is happening soon – it will be on May 11th and 12th – and it’s free and open to the public!!

We have two half days of interesting science talks and I’m so excited! This is a chance for many of the scientists working on the Project to tell us and you all about the great work that they are doing, the progress that the Project has made with our restoration work, and how our Adaptive Management Plan is guiding the science for the Project. Each session will include a panel with the scientists and opportunities for you to ask questions.

We have some terrific presentations lined up. Some examples:

Ben Pearl from the San Francisco Bay Bird Observatory will talk about the organization’s Western Snowy Plover research and related waterbird research (come for the science and the cute pictures!).
Several researchers from the U. S. Geological Survey will each talk about waterbirds, and mercury, and marshes (I think there will be some good pictures of mud in addition to birds).
There will be a talk about how salt marsh harvest mice are using the habitat in our restoration areas (more cute pictures).
Save The Bay will show how they are incorporating farming techniques into restoration of transition zone habitats (guaranteed pictures of a tractor).
And you may want to learn all about Motus towers and how scientists can use them to track birds, wildlife, and even some large bugs across their wide ranges of migration (cool pictures of antennas!).

I could go on and on...there’s so much more! But I don’t want to give away all the highlights. You can check out the agenda for yourself and register now here.

If you want to dig deeper and read up ahead of time on what the talks are about, you can check out the speakers’ abstracts here.

Hoping you can join us on May 11th and 12th!

Dave Halsing

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A Kayak Trip to the Island Ponds

Eric Larkin — Tue, 22 Feb 2022 21:21:21 +0000

A Kayak Trip to the Island Ponds Eric Larkin Tue, 02/22/2022 - 13:21

At long last, we have our very first guest post here at Salty Dave’s Wetland Weblog! There is an exciting story below, and I’m doing my best not to spoil it. But I can’t not mention up front how grateful I am for this authorial contribution — and even more for the actual event described in this piece:
A big-time tip of the cap to Eric Larkin and Steve Ochoa from the Western Sea Kayakers Club and to Kate Freeman from Ducks Unlimited for the daring, heroic, and hugely beneficial clean-up work they did!
With no further delay, here’s Eric Larkin…

This was not a posted trip of the Western Sea Kayakers (WSK) club, but on January 18^th, club members Steve Ochoa and I joined Ducks Unlimited biologist Kate Freeman as volunteers to scout out Alviso Pond A19 at the Don Edwards San Francisco Bay National Wildlife Refuge as a potential site for trash pick-up days and to pull out what trash we could ourselves.

I can’t recall how this happened, but Steve and I made it onto someone’s volunteer list. Ducks Unlimited reached out to us and asked for volunteers to visit the A19 pond via kayak to explore the feasibility of collecting debris after reaching it by water. Pond A19 is known as one of the “Island Ponds” because there is no land-based access to it. So, removing trash from there is a challenge.

The idea was that kayaks would be a good way to reach the Island Ponds safely, and most kayaks have spaces for bags of trash and debris to haul out. So we worked with Ducks Unlimited and the National Wildlife Refuge to get special permission to visit a site not normally open to the public and to plan the logistics.

The logistics were not easy: a big constraint is that the closest water access points are several miles of paddling away from Pond A19. Getting in and out of a kayak at low tides risks getting stuck in the very soft bay mud. So we had to time our trip just right.

In addition, the water temperature was 54 degrees Fahrenheit, cold enough that “cold shock” and hypothermia were real concerns. We all “dressed for immersion,” wearing either wet suits or dry suits, and carried safety gear like pumps, paddle floats, VHF radios, cell phones in dry bags, a Garmin satellite tracker, warm food and drink, and a change of dry clothes. We had training and experience to know how to drain our boats of water and reenter them should someone inadvertently capsize. A call to 911 means you’re on your own for at least an hour while sheriff or fire department first responders get their boat into the water and come looking for you. As sea kayakers, getting on tidal salt water is serious business, and not for the inexperienced and under-equipped.

Steve, Kate, and I opted to tackle getting to A19 via two different routes:

Begin at Coyote Creek trailhead, 1425 N. McCarthy Blvd, Milpitas, about 500 feet from Coyote Creek, then a 3.9-mile paddle to A19 against an ebb tide in the morning, and a flood tide in the afternoon. Steve launched from here on a WSK trip in 2011. Steve and Kate opted for this launch point, dropping their boats into the creek and getting on the water around 10:15 a.m.
Launch from Alviso Marina, via Alviso Slough and Coyote Creek, an 8-mile paddle to A19, with a mix of ebb and flood tides. This was Eric’s choice – on the water at 8:48 a.m.

Our destination was the southwestern breach in the A19 levee on Coyote Creek. A Google Earth view of both routes is available here.

We all arrived within minutes of 12:00 p.m., which I thought was pretty good planning (and paddling!) on everyone’s part. After a quick lunch, we got to work with contractor plastic bags, “grabbers,” and gloves, working our way along the inside of the levee. The prevailing afternoon winds are from the northwest, so we expected the southern levee of A19 to be a motherlode of flotsam and jetsam, and it was. Steve also paddled across the pond to the north levee and confirmed the pickings were good where we landed.

We found the usual stuff: bottles (some glass, mostly plastic), styrofoam from food delivery, small cosmetic containers and beauty products, many balls (tennis, soccer, basketball), a spent shotgun cartridge, and a large stuffed animal that was hemorrhaging powdered styrofoam out of fabric holes. We couldn’t take the sad animal, but we bagged it to stanch the bleeding, as it were, of its styrene particulate fluids, for a future pickup.

The most unusual part for me: I’ve been past here before and always thought the numerous white chunks visible from Coyote Creek were concrete fill from demolished road beds or building foundations. They are actually chunks of salt hardpan, from when the pond was an industrial solar evaporator and turned seawater into salt. The rain is gradually wearing the salt blocks away, some into fantastical organic shapes, but it gave the landscape a strange appearance, like other salt landscapes and formations around the world. Photos of them are here.

Our allotted time ran out quickly, and by 2:00 p.m., Kate, Steve, and I were back on the water, with 4 bags of debris lashed to our kayak decks (Kate had a bag fore & aft, Steve and I had one bag each, I believe). The tide had turned! Kate and Steve faced the relentless ebb of a full moon for 4 miles and were off the water by 3:15 p.m. After a boost on Coyote Creek, I faced the same relentless ebb for 4 miles after turning into Alviso Slough, arriving back at 5:04 p.m. to a beautiful sunset.

It was good to visit this area again and see it gradually transform into the living and vital saltwater marsh it was.

Despite the challenges, this trip was fun and rewarding and a successful scouting effort. We are hoping this will be the first of many such trips to clean up this former industrial salt pond, and we will be interested in volunteers from the Western Sea Kayakers or from other groups or individuals.

Special Note on making that a reality: This location is in a part of the Don Edwards National Wildlife Refuge that is usually closed to the public. We were granted special permission as a planned trip with Ducks Unlimited to assist with an active construction project. In addition, the Island Ponds close from February to September for the breeding season of the California Ridgway’s rail, an endangered bird species. This trip and future trips to the Island Ponds require a Special Use Permit in advance to enter this newly enhanced restoration site usually closed to kayaks and most other forms of public access. [Editorial comment from Salty Dave here: we’ll be happy to work with Refuge managers to secure Special Use Permits for these kinds of organized and well-planned group trips in the future. But in case it’s not clear from Eric’s post, please Do not paddle there on your own. It’s unsafe, illegal, and disruptive to wildlife. Thanks!]

Please contact me at [email protected]">[email protected] if you want more information on future trips or on WSK.

Back to Salty Dave here: How about that as a thrilling adventure on the wildly varying tides of the far South Bay?!?! I am honored that Steve, Eric, and Kate took on this task, and I am hoping that I can join their next trip out. Kayaking is an excellent way to experience the more remote areas of the Bay. More of their excellent pictures are available here.

Dave Halsing

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Eric Larkin