Dear Jane and Grebe Lovers,
It’s been a challenging week on the River! For the last week or so, I have been watching anxiously as two small Pied-billed Grebes have tried their best to resist the powerful force of human encroachment onto the river. I have named these two feisty little creatures Podilymbus and Podiceps, based on their full Latin name Podilymbus Podiceps. I call them both Podi for short.
The story starts when I I heard on July 13 that the City was planning to begin its annual flood control work on the river levee on Monday, July 16! I was shocked! This is the earliest it has ever begun, at least in my memory. You and I, Jane, innocent of their plans, had both written the Public Works Department several weeks earlier, asking them to move the start date from early August to September 1, so as to avoid any interference with the breeding season. Instead, they moved it even earlier than we could have imagined! And neither of us has yet been told why, even though we have both inquired as to the reason. I personally think it has to do with finances. What a disappointment!
When I heard about the earlier-than-usual start date, my adrenalin started flowing again as it does each year. Flood control means chainsaws, tractors, mowers and lots of racket. It means massive destruction of habitat for not only birds but hundreds of other creatures – mammals, rodents, turtles, snakes, insects. Yes, it may help protect our City from a 100-year flood. Indeed, I myself live in that flood plain. But at least let’s admit up front that we shouldn’t have settled on the flood plain in the first place. And I think we owe it to those wild creatures, who lived and raised families long before we took it over, to do what we can to ease their situation.
Pied-billed Grebes are the most vulnerable nesting population right now, at least among the waterfowl. The Mergansers and Wood Ducks nest north of Highway 1, in more thickly-wooded riparian habitat, out of the reach of the flood control operation. I believe all their young have already fledged. The Mallards still have some tiny babies on the River, but I’m hoping that at least their very vulnerable nests on the levee banks have now been vacated. But I worry about the Grebes.
I have been out on the river looking for Grebes almost every day since I heard that the start date would be so early, getting out much earlier and later than usual. That’s been a plus, being on the river in very early morning and again at sundown! It’s beautiful at that time.
On July 14 I heard Podi and Podi calling, then found them hovering around a tule clump just north of the Water St. Bridge, only about 20 feet from where the flood control work was to begin. I immediately posted to eBird that I had seen two Pied-billed Grebes together in a ‘suitable breeding habitat’. Then I wrote Public Works and the contracting biologist about the existence of the pair and the suitable habitat. On July 15,
I decided to go out at sundown to see if I could catch Podi and Podi entering the clump for the night. It was a good guess. I did see them go in, and although I waited at least 20 minutes, I didn’t see either of them re-emerge. (Unlike Mallards, the Grebes are almost always seen alone, except occasionally during breeding season, and even then they fish alone and then take turns incubating the eggs.)
The next morning, the day the big chainsaw extravaganza was to begin, I stood on the Water St. Bridge watching Podi and Podi, both swimming nearby. Then, to my delight, I saw Podilymbus, or was it Podiceps, carrying a long trailing green stalk in her mouth, swimming towards the tule clump. My guess was right! They were almost surely building a nest. I strained my eyes through my binoculars, but just couldn’t see anything definitive.
Just about then, Gary Kittleson came along. He is the biologist who contracts with the City every year to do a wildlife survey of the river before the mowing onslaught begins (the survey is required by California State Fish and Wildlife.) I told him about the Grebes and showed him the tule clump where I had just seen at least one of the Podi’s enter. He raised his binoculars and almost immediately saw what I hadn’t been able to see – Podiceps (or was it Podilymbus) actually weaving the tules together to build the nest. He helped me catch a glimpse as well! Gary had just returned from Alaska where he was documenting some breeding Grizzlies, pretty exciting stuff. But even he got very interested when he saw one of the Podi’s actually weaving the floating nest together and securing it to the anchored tules surrounding the nest. The thicket was too dense to get a photo, but here is a photo of the Grebe nest I found in 2015 near Mimi de Marta Park.
We then walked back to the staging ground of the day’s operation, where Gary reviewed with the clearing crew what vegetation they were required to cut and what they were required to leave. You can imagine how happy I was when I heard him tell them about the Pied-billed Grebe nest! They were very receptive. Some of them really care about the birds.
Sadly, this nest was not destined to survive, although not primarily through the fault of the flood control work. Coincidentally, I think, on July 18, the City decided to artifically breach the sand bar that blocks the river mouth. The sand bar allows the lagoon to form each year, pushing water back up the river channel, as far as Highway 1 and beyond. Podi and Podi’s nest was floating on that water! All the noise of the mowers and chainsaws, only 20 or so feet from the nest, may have contributed to the almost immediate abandonment of the nest. But the nest wouldn’t have survived anyway. By nighttime on the 18th, the water level had dropped about 2 feet or more. I couldn’t see it, but it was not hard to imagine that the painstakingly woven nest would have been left dangling from an anchored tule, and then probably dumped or tipped sideways into the water, undoing all the hard work of Podilymbus and Podiceps. Gary Kittleson was able to wade in several days later and confirm the nest, but found the no eggs.
Most Pied-billed Grebes nest on quiet bays, in marshes, or on lakes. In their wilder or more desperate moments, a grebe may choose a sluggish river. Our intrepid pair had chosen a relatively quiet, backed up river. But they unknowingly had also chosen a river where the interests of commerce, residents, city government and the Army Corps of Engineers take precedence over protection of wildlife.
For a couple of days, the grebes hung around the abandoned nest, then apparently gave up on it. They have now moved downriver towards the Benchlands area and are now hovering near and entering a stand of tules near the south end of a small channel between the Chinatown Bridge and the Soquel Bridge, on the West Bank. Sadly, that is just where the tractors and chainsaws are moving next, probably this week. I saw two of them enter there just this morning around 7:30 a.m. Will they try to build a new nest? It is late in the season. The biologist Gary Kittleson is also monitoring the situation and will continue notify the City.
I just want to add that the sand bar itself is not an entirely natural phenomenon but one that is also affected by human activity. As I understand it, the annual buildup of sand at the San Lorenzo river mouth is caused by a phenomenon called littoral drift, in which sand is transported along the length of an ocean shore because of wave action. This natural flow of sediment along our coast is partially blocked by the jetties built out from the Santa Cruz Harbor. This exerts backward pressure, increasing the amount of sand that collects at the San Lorenzo River Mouth, thus exacerbating the annual sand bar problem. Our problem occurs when the water rises. Podilymbus and Podiceps suffer when the water is suddenly and unpredictably pulled out from underneath them.
I know you have felt discouraged, Jane, by the annual actions of Public Works. But, to tell the truth, in spite of everything terrible that happens each year, I have actually felt this season that we are making progress. Here is a list of the things that have changed for the better during the four years we have been working together with the Department:
- On the upper reach, north of the Water St. Bridge, the Department now protects 15 feet of vegetation along the riverbank, as required by City Documents, rather than the 5 feet originally protected.
- A biologist now instructs the mowing crew on the specifications of what to cut and what not to cut, rather than leaving it to the foreman of the crew.
- For the first time this year, the 15 feet is flagged by someone from the Public Works Department, rather than the foreman of the crew.
- For the first time this year, some native shrubbery and perennials – in areas normally scalped to the ground – were flagged for protection
- So far we have been able to protect Riverbend Park – where large cottonwoods and alders were originally slated for removal.
So let’s stay hopeful and work hard next year to (1) get a later start date, (2) require removal of invasives like the pampas grass we have seen, and (3) flag more natives for protection.
On a positive note, I saw my first kestrel on the river two days ago – thanks to Michael
Levy who recognized the call and pointed the adult male out to me as it landed in a nearby redwood tree. This was one of the birds that Alex Rinkert of the Breeding Bird Atlas project asked us to especially look out for on the River. These birds formerly nested along the San Lorenzo River but haven’t been observed or reported for several years. Could it have a nest nearby?
One day later I found this mosaic of a kestrel by the amazingly prolific and bird-conscious artist Kathleen Crocetti. It wasn’t far from where I saw the real bird, on the wall separating Front St. from the river, across from Trader Joe’s. The permanent exhibit includes 80 (!) bird mosaics, mostly by Kathleen’s students, as well as lots more of fish and insects. It must have been fun to break all those plates!
Let us all keep our eyes open for anything and everything . There’s way more to see on our River than people dream of.