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Yesterday I had some time to kill before getting a COVID test, and, as usual, wandered down to the ocean. This time I was at Seacliff State Beach. It was pretty crowded, so I walked onto the pier to see if the fishermen were having any luck. They weren't, really. One man kept catching jack silversides (Atherinopsis californiensis) that were too small to keep. There was a lot of banter about sharks and bait and crabs, but what I witnessed yesterday confirms my hypothesis that a lot of what people call "fishing" is merely an excuse to get outside for a few hours. And there is absolutely nothing wrong with that.

As for me, I have nowhere near enough patience to make a decent fisherman. I did, however keep myself amused by eavesdropping on their conversations and writing snippets in my nature journal. I did also find myself mesmerized by the anchovies. Watch for yourself.

Northern anchovies (Engraulis mordax) at Seacliff State Beach
2021-11-23
© Allison J. Gong

Like sardines, anchovies are planktivorous filter feeders. If you watch the video again and can focus on an individual fish for a while, you'll see that as it swims forward, the front end becomes white and bulbous for a few seconds. That's sunlight reflecting off the fish's jaws. Anchovies have metallic silver coloring, which is a defense against predators. For fish that live in surface waters that are brightly lit, all of those glinting flashes of light make it difficult for a predator to zero in on a single fish to pursue. There is safety in numbers, and for anchovies the silvery coloring combined with schooling behavior means that if a predator manages to catch some of the fish in the baitball, most will avoid being eaten. This works against predators such as larger fish, squid, and birds, which generally capture one or a few fish at a time. But if the predator happens to be a humpback whale, which is capable of engulfing the entire school, then the anchovies are SOL. Think about it, though. For any anchovy, the probability of encountering a larger fish, squid, or bird is much higher than encountering a humpback or blue whale. Thus the selective advantage of schooling!

Okay, now back to the feeding. Anchovies have really long jaws for their size and can, like snakes, open their mouths very wide. This allows them to filter as much water as possible as they swim. Food, mostly plankton, is caught on the gill rakers, which are bony or cartilaginous structures projecting forward (i.e., towards the mouth) from the gill arches. Some fishes' gill rakers are nothing more than short nubs. Filter feeding fishes such as anchovies have long thin gill rakers. Water enters the mouth as the fish swims forward, and plankton is caught on the array of gill rakers. The water then passes over the gill filaments, where respiratory exchange occurs, and then out from underneath the operculum. Anchovies cannot suck water into their mouths, and thus can feed only while swimming forward, or ramming water into the mouth. This is a type of feeding called ram feeding.

These anchovies were very close to shore. They were feeding, so obviously there was plankton in the water. I haven't done a plankton tow in a while, as I generally assume that fall/winter plankton isn't as interesting as spring/summer plankton. However, given the presence of feeding anchovies inshore, it might be time to test that assumption.

I go to Natural Bridges quite often, to play in and study the rocky intertidal. But at this time of year, before the low tides really get useful, there is another reason to visit Natural Bridges—to see the monarch butterflies (Danaus plexippus). Natural Bridges State Park is a butterfly sanctuary, providing a safe overwintering spot for migrating monarchs.

Yesterday morning, while it was still cool enough for the butterflies to be hanging in clusters, I went out and photographed them. Last year's count was only 550 for the winter, but I'd heard that there were more butterflies this year and it was definitely worthwhile going out and looking for them.

Monarch butterflies clustered in eucalyptus tree
Monarch butterflies (Danaus plexippus) at Natural Bridges State Park
2021-11-06
© Allison J. Gong

The butterflies rest with their wings up, so when they are hanging like this you see the duller underside of the wings. A few of them were starting to warm up their flight muscles and showing off the more brilliant orange of the dorsal wing surface.

Monarch butterflies clustered in eucalyptus tree
Monarch butterflies (Danaus plexippus) at Natural Bridges State Park
2021-11-06
© Allison J. Gong
Monarch butterflies clustered in eucalyptus tree
Monarch butterflies (Danaus plexippus) at Natural Bridges State Park
2021-11-06
© Allison J. Gong

I am really not good at counting things like this, but my guess is that there were hundreds of butterflies, all told. Based on the 2020 season, when I didn't see any monarchs at all at my house and only a few scattered individuals at Natural Bridges, this year's population seems to be doing much better. 2020 was an awful year in California in general, and in the Santa Cruz region in particular. The CZU August Lightning Complex fire put air quality into the unhealthy-for-everybody range for several weeks. Much of the rest of the western U.S. also burned, with much habitat loss for nature. Maybe that's part of why there were so few monarchs last winter in Santa Cruz. Of course, the monarchs' populations have been declining for years, so last year's population crash may be only a dip in the grand scheme of things.

Whatever the cause, it really was good to see even this many butterflies at Natural Bridges.

Oh, and before starting my butterfly hunt in earnest, I spent about an hour watching and listening for birds. I wanted to get the birdwatching in before human activity drowned out the birdsong. Unfortunately, most of what there was to hear was the cawing of crows.

Nature journal page of birds seen and heard
Page from my nature journal

Next time I'm at Natural Bridges, I'll try to remember to check in with the visitor center to see what the official count for monarchs is. Fingers crossed the number is a lot higher than 550!

Over the weekend the atmospheric river slammed into Northern California and settled over us for a few days. Our weather station at home, roughly at sea level, measured 4.5 inches of rain. On Sunday afternoon it was extremely windy, and I think the rain wasn't falling vertically enough to be captured by the rain gauge, and my guess is that another half-inch or so fell but wasn't measured. A total of about 5 inches of rain feels right.

This storm was a very big deal for us, for a couple of reasons. The most obvious is that California is in the midst of another severe drought. There wasn't much rain or snowfall at all in the 2020-2021 rain season, reservoirs are drier than I remember seeing them, and the governor has asked residents to reduce water consumption statewide by 15%. We are woefully short of that conservation mark. So yeah, the amount of water available to all consumers is (or should be) of concern to all of us.

A second reason why we all paid so much attention to this storm was the fact that much of the rain was forecast to fall on areas that had burnt recently, including the 2020 CZU Lightning Complex fire burn scar. Both the 2020 and 2021 fire seasons were horrendous, leaving many acres of previously forested land bare and prone to mudslides, or "debris flows" in modern parlance. Residents in the Santa Cruz Mountains were warned to prepare for evacuation, just in case. And everyone was prepared to deal with power outages, which, oddly enough, didn't happen.

On Friday the 22nd, before the major storm blew in, I went to Younger Lagoon to record some video clips for my Marine Biology class. One smaller storm had already blown through and it was very windy. I encountered two birders who were looking for pelagic birds that had been swept into the lagoon or were seeking shelter from the elements.

This is what the lagoon looked like on Friday:

North end of Younger Lagoon
Younger Lagoon
2021-10-22
© Allison J. Gong

In fact, here's the video I put together for the students:

So that was Friday. On Saturday we went hiking at Moore Creek Preserve with our god-daughter and family. We all wanted some quality outdoors time before the major storm event on Sunday/Monday.

Yesterday (Monday) I went back to Younger Lagoon to see how much it had changed with all the rainfall. I could tell from the smell that the sand berm hadn't been breached yet. We can always tell when the lagoon breaks through, because all of the hydrogen sulfide buried in the sediment gets into the air. It's a smell that, once known, is difficult to forget. Anyway, I took a photo of the top of the lagoon from the same spot as on Friday. And see how much difference one big rain event can make:

Younger Lagoon
2021-10-25
© Allison J. Gong

To make the comparison easier, let's look at those photos side-by-side:

We had a high surf advisory yesterday, so I wandered down into Younger Lagoon to check out the ocean conditions. I could hear that the surf was really big. It was still windy, too.

Just to make sure my intuition was correct, I stopped to check out the sand berm. And yes, it was still there.

Sand berm between the Pacific Ocean and Younger Lagoon
2021-10-25
© Allison J. Gong

The waves were big and the sets were coming in fast. I shot this video at about low tide yesterday morning. We're in neap tides right now so the low wasn't very low.

High surf advisory at Younger Lagoon
2021-10-25
© Allison J. Gong

Storms and tidal surge, when combined, can wreak havoc on nearshore coastal habitats. One of the obvious victims of the recent violence is the kelp bed. The kelps have been on their seasonal decline for weeks now, and the storm-strengthened swell tore up a lot of kelp and deposited it on the beach. Thousands of detached pneumatocysts (floats) of Macrocystis pyrifera had been blown into windrows. The lighter colored pneumatocysts are the ones that were washed up earlier, probably in the second-most-recent high tide; the darker ones were deposited during the most recent high tide, about six hours earlier.

Kelp debris, mostly Macrocystis pyrifera, on the beach at Younger Lagoon
2021-10-25
© Allison J. Gong

I expected to see dead animals on the beach, too, and was surprised that there weren't any carcasses in sight. Then I looked across the beach with binoculars and saw a couple of turkey vultures (Cathartes aura) on the sand, and a third on the fence above. Vultures eat carrion, so there must be a corpse over there after all. Sure enough, there was a dead bird. As I approached I saw a black body with a smaller reddish part, and my first thought was, "Are turkey vultures cannibals? Will they eat their own dead?" because turkey vultures have unfeathered red heads. But when I got closer I could see that this corpse had webbed feet. It was, in fact, a cormorant.

Dead cormorant at Younger Lagoon
2021-10-25
© Allison J. Gong

The scavenging turkey vultures flew away as I approached. I didn't want to interrupt their brunch any longer than necessary, so stuck around just long enough to snap a few photos. By the time I had crossed back to the near side of the beach, they had returned to their feeding.

All told, this storm was a good start to the rain season. It put an end to the fire season, which is a huge relief to all of us living in California. We have a long way to go to return to normal rain levels, whatever they are in this era of anthropogenic climate change, and it irks me to hear people saying that we've had a lot of rain now, so the drought must be over. Too bad it doesn't work that way, or we would all be rejoicing big time.

Climate change models predict, among other things, oscillation between extreme rain events and extreme drought in California. Just in the past handful of years we've had drought plus the Blob (2015), a wet winter in 2016-2017, and a return to dry conditions from 2018-2020. And we all remember the extreme fire seasons of 2020 and 2021. So what is "normal" these days? I think it's impossible to know. We are experiencing climate change as it happens, and we don't know how or when things will begin to stabilize. I suspect it won't be within the lifetime of anyone reading this blog.

Still, after having about zilch in the way of rain last year, it's good to see that Mother Nature can still throw an atmospheric river at us. Fingers crossed for more rain as the season continues.

Over the past couple of weeks I've rented two super telephoto lenses, to see what all the hype was about. I mean, do I really need 500 or 600mm of reach? I had read up on the specs of such lenses, and one major drawback is the weight—1900 grams or more. Would I be willing to lug a beast like this around, and would I be able to use it effectively? You never know until you try, so I rented them. And, of course, it was foggy both weeks so I didn't have much opportunity to take decent photos. But since the entire point of renting the lenses was to see if I could use them at all, that was fine.

As part of the test-drive for the second lens, I went up to Waddell Beach to see if there would be any birds to photograph. It is migration season, and our winter residents will be arriving soon. Some of them, such as the red-necked phalarope, have shown up at Younger Lagoon over the past four weeks or so. It was really foggy at Waddell, remember, and I didn't have much hope of seeing anything remarkable. There were some gulls and whimbrels off in the distance. But it turned out that the stars of the show were blackbirds!

They were hard to miss, because there were 50-60 of them and they were hopping up and down like jumping beans.

This is a mixed flock of Brewer's blackbirds (Euphagus cyanocephalus) and red-winged blackbirds (Agelaius phoenicius). The glossy greenish-black birds are the male Brewer's blackbirds, and most of the brownish birds are female Brewer's blackbirds. Since both sexes were doing the hopping, I didn't think this behavior had to do with courtship or mating.

So yes, while most of the birds seemed to be Brewer's blackbirds, I did hear the liquid gurgling of the red-winged blackbird's song coming from somewhere in the flock. When I got home and looked at the photos on the big monitor, I did see some red-winged blackbirds. Here's a male, surrounded by other males red-wingeds and both female and male Brewer's blackbirds.

Male red-winged blackbird (Agelaius phoenicius) at Waddell Beach
2021-09-14
© Allison J. Gong

In this photo above the black birds are male Brewer's blackbirds. The brown birds without faint wing bars are female Brewer's blackbirds, and the brown birds with the wing bars are male red-wingeds. There were no female red-winged blackbirds in any of my photos. According to an article from Cornell's Bird Academy, the males spend the weeks leading up to springtime competing for territories, and when the females return from their winter migration they will choose mates based partly on the quality of the territory. Mid-September is too early for this kind of competition, though. We are just about up to the autumn equinox, but not near winter quite yet.

Back to the hopping. There's a clue in this photo about what I think was going on:

Male Brewer's blackbird (Euphagus cyanocephalus) at Waddell Beach
2021-09-14
© Allison J. Gong

See that little fly? There were many such flies, most of which were lower on the beach gathering around the kelps and other wet detritus that had washed up. There were fewer flies up where the driftwood accumulates, though. Once again, it wasn't until I saw the pictures on my big monitor that I could figure out what those blackbirds were doing. They were hopping up to eat flies!

Here's a series of shots showing one of the male red-wingeds in mid-hop.

  • Looking up, just before the hop:
Male red-winged blackbird (Agelaius phoenicius) at Waddell Beach
2021-09-14
© Allison J. Gong
  • Up he goes! See the very edge of the red epaulette on his right wing? And all those flies?
Male red-winged blackbird (Agelaius phoenicius) at Waddell Beach
2021-09-14
© Allison J. Gong
  • Is he going to catch something?
Male red-winged blackbird (Agelaius phoenicius) at Waddell Beach
2021-09-14
© Allison J. Gong
  • Maybe?
Male red-winged blackbird (Agelaius phoenicius) at Waddell Beach
2021-09-14
© Allison J. Gong
  • After all that, I'm not at all sure if he actually got anything!
Male red-winged blackbird (Agelaius phoenicius) at Waddell Beach
2021-09-14
© Allison J. Gong

I don't have any hard evidence that the blackbirds (both Brewer's and red-wingeds) are catching flies. And while I was at the beach watching them hopping up and down I had no idea what they were doing. However, now that I've seen the flies in the photos, it makes sense that the birds would be hopping up to catch and eat them, especially since both sexes of the Brewer's blackbirds were doing the same thing.

So that's what was hoppening at the beach!

1

One year ago today a lightning storm settled over the Santa Cruz Mountains and dry lightning ignited a bunch of wildfires. Given the drier-than-normal conditions at the time the fires took off like crazy and eventually merged into one megablaze that CalFire dubbed the CZU Lightning Complex fire. The CZU Lightning Complex fire burned over 80,000 acres in Santa Cruz and San Mateo Counties before being contained by CalFire on 22 September. It raged through Big Basin Redwood State Park and destroyed the buildings at the park headquarters up in the mountains. Several mountain communities were threatened, with over 1400 structures destroyed. I personally know two families whose homes were lost, and many others who evacuated. We were also ready to evacuate, with bags packed and a place to flee to.

To commemorate the first anniversary of the CZU Lightning Complex fire the Santa Cruz Museum of Natural History and the Santa Cruz Public Library put together a series of events called "CZU and You" to teach the public about this particular natural disaster. This past weekend we attended a walk through Rancho del Oso, led by Richard Fletcher, who is one of the California State Parks interpretive rangers. Rancho del Oso sits in a little valley that I think of as the "bottom" of Big Basin Redwood State Park. It ends at Highway 1 directly opposite Waddell Beach. In previous years I have taken my Ecology class to Rancho del Oso for the first field trip of the semester. Rancho del Oso was cleared to reopen for visitors on weekends only just a few weeks ago.

My nature journal entry
2021-08-14
© Allison J. Gong

The Nature and History Center at Rancho del Oso is housed in the building that was the residence of Hulda Hoover McLean, who was the niece of President Herbert Hoover. Hulda and her husband, Charles, raised a family in the Rancho; Hulda taught her children about the natural history of the area. She sold her 40 acres of land and her home to the Sempervirens Fund in 1985, with the intent to create a place where people could visit and learn about this part of the natural world. There was one ranger on site on August 16, 2020 when dry lightning ignited the fire on the hillside directly across Waddell Creek from the nature center. He managed to flag down a single fire truck and crew. Working through the night this handful of people built a backfire to burn up the hill towards the flames that had sped around the house and were approaching from the other side, and sweeping off the burning embers that landed on the roof

The first things that Ranger Fletcher showed us were some cones from Monterey pine (Pinus radiata) trees. He described this species is being moderately serotinous, meaning that seeds don't fall out of the cones until they are exposed to the heat of a fire. Heat dries and opens up the cones, allowing the seeds to fall and be dispersed.

In the area this backfire burned, literally across the driveway from the nature center, we could see some of the fire followers. These are the first plants to show up after a fire. Some of them may have arrived by seed, but many are regrowth from underground roots or bulbs.

The naked lady lilies (Amaryllis belladonna) are non-native ornamental bulbs that have been planted in gardens all over the region. They are called naked ladies because their leaves die back completely before the stalk blooms in late summer; you can see all the brown leaves at the bases of the flower spikes. In this first bloom season after the fire they seem more vibrantly pink than usual. The other foliage in the foreground is a blackberry (Rubus sp.) that could be either native or not. In the background you can see some bracken fern (Pteridium sp.).

Naked ladies (Amaryllis belladonna) in burned area at Rancho del Oso
2021-08-14
© Allison J. Gong

After a disturbance such as a fire the process of ecological succession is reset. Given the European colonizers' habit of suppressing all fire, it had been at least 100 years since the Waddell Valley burnt. In the many decades since the previous fire the homesteaders and ranchers had planted all sorts of non-native ornamental plants in their gardens. The naked ladies and invasive blackberries are examples of plants that are well suited for our Mediterranean climate, and they certainly made a showy return after the CZU Lightning Complex fire.

Fortunately it's not just the non-natives that are coming back. The ranger was excited to point out that one yellow bush lupine (Lupinus arboreus) had popped up on this same slope. Lupines are good plants to have on burnt slopes because they help stabilize the soil. They are also nitrogen fixers, which makes the soil more hospitable to other, hopefully native, plants.

Bush lupine (Lupinus arboreus), bracken fern (Pteridium sp.) and naked ladies (Amaryllis belladonna) in burned area at Rancho del Oso
2021-08-14
© Allison J. Gong

One plant that I hadn't expected to see in this location is Equisetum, the horsetail. There is a lot of Equisetum along the Marsh Trail, and I associated this plant with wetlands. So why was it growing on this particular slope, which is measurably drier than the Marsh Trail? It was growing really well, too!

Equisetum in burned area at Rancho del Oso
2021-08-14
© Allison J. Gong

And see how lush it is growing along the Marsh Trail?

Equisetum along Marsh Trail at Rancho del Oso
2021-08-14
© Allison J. Gong

We hiked the Marsh Trail—how could there be so many mosquitos when we're in such a bad drought??—and crossed Waddell Creek to where the Skyline to the Sea trail ends (or begins, if you were to start at the beach and hike uphill). This is where Ranger Fletcher told us more about the fire itself and its ongoing effects.

We were hiking at Rancho del Oso on a foggy morning. It was so very different last year, when the marine layer abandoned us early in the summer and left us to dry out just in time for the dry lightning in mid-August. But this is the area where the first lightning strikes hit ground:

Hillside northwest of Waddell Creek, where the Waddell fire began
2021-08-14
© Allison J. Gong

Once the fire was extinguished this hill was covered with black, burnt vegetation. Anything green is vegetation that has grown since then.

CalFire declared the CZU Lightning Complex fire contained on 22 September 2020 and controlled on 23 December. What nobody knew at the time was that the fire remained burning underground. Considering their great height, redwood trees don't have deep roots. But they have lateral networks of roots that entwine with those of neighboring trees (which are likely to be clonemates) and form a more or less solid mesh that holds all of the trees up. The fire travelled along this root network and continues to burn. One of our group asked "What is there to burn, if the roots have already burnt?" and Ranger Fletcher explained that now there are tons of charcoal buried in the ground, and we all know how well charcoal burns, right? Not being able to detect where roots are burning underground means it's difficult to evaluate trails and know when they are safe. Just last week a ranger was working up at Big Basin and stepped into what turned out to be a cavern containing burning embers. CalFire estimates that the fire will continue to burn underground for another four years. Trees that were weakened or killed by the fire will also be falling. It will be several years before the Skyline to the Sea trail opens again. But in the lifespan of a redwood forest, five or even ten years would be a blink of the eye. And I'd just as soon not step into a burning hole while hiking, thank you very much.

On this side of Waddell Creek you can see the meadow that acts as a buffer zone between the mountains and the ocean. When wildfires burn through hilly areas, we worry about winter rains causing mudslides. This past winter we got hardly any rain at all, so at least the mudslides didn't materialize. But even when there aren't mudslides, a lot of nutrients wash downhill towards the ocean. The meadow is a biological sponge that soaks up these nutrients and keeps them from creating problems in the marine habitat. This is one of the reasons that wetlands are such important players in the health of coastal ecosystems. I took this photo from the Highway 1 bridge that crosses Waddell Creek. Just on the other side of the highway the creek spills onto Waddell Beach.

Waddell Creek and flanking wetlands
2021-08-14
© Allison J. Gong

From a fire behavior perspective the CZU Lightning Complex fire was unusual. Fires usually burn up hills, but this one burned downhill towards the ocean. Waddell Beach is almost always foggy, and the marine layer can be felt away from the beach, as it was on our most recent visit to Rancho del Oso. This marine influence should have acted to keep the fire from racing downhill as fast as it did. Alas, the marine layer was not doing its job last summer. If it had been, we wouldn't have seen so many lightning strikes in the first place. The paucity of rain from the previous winter didn't help things, either. Climate change is coming back to bite us in the ass. Around the world we are seeing extreme weather events, from severe drought to equally devastating floods to heat records tumbling by the wayside. We are living in the era of anthropogenic climate change, and we will not be alive when an equilibrium returns to Earth's climate. In the timeframe of a human lifespan, however, it is nice to see and document how this small part of the landscape is recovering from last year's fires. Now that Rancho del Oso is open again I'll try to get up there every so often to record changes in my nature journal.

A week ago I snagged a stint with a traveling nature journal that is making the rounds. It's a nature journal that is being sent to whoever wants to take it. Each user keeps the journal for five days or until five pages are filled, then sends it on to the next person. I was lucky enough to be the first person to respond when it became available, and the journal arrived chez moi this past Monday.

I gotta say, thumbing through the journal and looking at the work of the folks who had it before me was both thrilling and a little intimidating. But it was so exciting to get to study other people's nature journal pages. Just seeing the different styles and focuses was a fantastic learning experience for me. At first I wondered how the heck I would find five pages' worth of stuff to write/draw about in five days. However, something about having the book in hand released the mental block and stuff just flowed onto the pages. Oh, there was a lot of erasing and a little trepidation the first time I put pen to paper, but overall it was a lot of fun.

Anyway, here are my pages.

Monday 2021-05-17 I found the not-so-secret nesting spot for the Brandt's cormorants. This is apparently a new site for them. I had a lot of fun with the cormorants on the rock—all those postures to study and draw! And I'm very pleased with the larger pair in the corner. They actually look like cormorants!


Tuesday 2021-05-18 The journal has both white paper and tan toned paper. Nobody had used any of the toned pages yet. I decided to use it for these sketches of blooming sand plants. My favorite sketch on this page is the California poppies.


Wednesday 2021-05-19 While flipping through the photos I had taken at Asilomar over the weekend, I decided to draw some of the molluscs. My favorite on this page is the turban snail. And octopuses are really hard to draw!


Thursday 2021-05-20 I used my last two pages to diagram sea urchin larval development. The difficult thing about this page was getting the layout to flow the way I wanted. I used about half an eraser, trying different arrangements of text and drawings! The sketches themselves were not that difficult, as I've drawn these larvae many times before.


So there you have it—a week's worth of nature journaling. It was an immense honor and pleasure to participate in this living document of nature observations. I've sent the traveling journal up to Anchorage, Alaska, and am excited to see what the next person does with it.

1

As we speed towards the summer solstice the days continue to get longer. The early morning low tides are much easier to get up for, as the sky is lightening by 05:30. Even so, when traveling an hour to get to the site, it's nice when the low is later than that. This past Saturday the low wasn't until 08:00. My parents were in Monterey for the weekend, so I decided it would be a good day to work the tide at the southern end of Monterey Bay, and then visit my parents. The Monterey Peninsula has some of the most spectacular tidepooling terrain in the region, and if I lived closer you can bet I'd know those sites better. Not that there is anything at all wrong with the sites on my end of the Bay and up the coast. But sometimes it's good to get out of one's comfort zone and explore the less well known.

Rocks and tidepools
Rocky intertidal at Asilomar State Beach
2021-05-15
© Allison J. Gong

So explore we did. It was cold and windy. The tide wasn't all that low and the swell was up, so we didn't get beyond the mid-tidal zone. My hip boots have deteriorated to the point that I have pinprick leaks at the seam where the boot part meets the leg part. Usually the tiny leaks don't bother me, but when the water is cold I definitely feel the trickles. What all this means is that I didn't get down into the low zone, which is fine. Biodiversity is highest in the mid zone anyway. The mediocrity of the low tide meant that I had to keep an eye out for sneaker swells, so less heads-down poking around and more scanning from above and then zooming in on individual items of interest.

One thing we noticed right away is that groups of Tegula funebralis, the black turban snail, were clumped together above the waterline of the high pools.

I'm trying to decide whether or not this is noteworthy. The pattern did catch my eye, but that might be only because it's unusual (although not particularly interesting). It was a cold and drizzly morning, so the snails didn't have to worry about desiccation. Was the clumping together benefiting the snails in any significant way? Hard to say.

The T. funebralis were also clumping together in the water! Here's a large clump of Tegula shells in a pool.

Clump of black turban snails in a tidepool
Black turban snails (Tegula funebralis) and one hermit crab (Pagurus samuelis)
2021-05-15
© Allison J. Gong

Almost all of these are snails, but can you see the one that is a hermit crab?

Poor Tegula funebralis. It is so common that it is invisible and vastly underappreciated. I find them quite charming, though. There's something about a grazing snail's slow way of life that is very soothing. Not that you might not fall asleep waiting for them to do something interesting, but it is good to slow down to the pace of nature. Anyway, Tegula is one of my favorite animals, precisely because it is so unassuming and ignored. One of delightful things about Tegula funebralis is when it plays host to Crepidula adunca. I've written about the biology of C. adunca before and don't want to rehash that here. I just wanted to show off my favorite photo of this trip to Asilomar:

Black turban snail with two attached slipper snails
Black turban snail (Tegula funebralis) wearing two slipper snails (Crepidula adunca)
2021-05-15
© Allison J. Gong

I don't know why I like this photo so much. It certainly isn't the best shot I've ever taken. There isn't any vibrant color at all. The subjects are the same color as the background. But it works for me.

When it comes to a snail's pace, you can't find anything slower than Thylacodes. That's because Thylacodes squamigerus is the snail that lives in a calcareous tube. Much like a barnacle, or the serpulid worms that have similar tubes, Thylacodes makes one decision about where to live and lives there for the rest of its life. I see Thylacodes at places like Pigeon Point up north, but they are much more abundant on the Monterey Peninsula.

Tube snail (Thylacodes squamigerus)
2021-05-15
© Allison J. Gong

And the snail winners in the Most Likely to be Overlooked have got to be the littorines. These little snails (most of which are smaller than 15 mm) live in the highest intertidal, where they get splashed by the ocean just often enough to keep their gill sufficiently moist. They are never entirely submerged, but they do tend to gather in cracks, even the tiniest of which will hold water longer than a flat rock surface.

Littorines (Littorina keenae) in the splash zone
2021-05-15
© Allison J. Gong

If you look closely at the photo above, you might see pairs of mating snails. Given where they live, high up in the intertidal where they are rarely covered by water, broadcast spawning isn't a viable option for the littorines. They have to copulate. There are, I think, eight copulating pairs in this group of ~30 snails.

Copulating pairs of Littorina keenae
2021-05-15
© Allison J. Gong

Because Littorina's habitat makes broadcast spawning an unfeasible option, the snails must lay eggs. But the splash zone isn't a very friendly place for the eggs of marine animals. The littorines lay eggs in gelatinous masses in crevices or depressions where water will remain. After a week or so of development, the egg mass dissolves as it gets splashed, and veliger larvae emerge. They recruit back to the intertidal after spending some period of time in the plankton.

When all is said and done it's difficult to make the claim that snails live exciting lives. Nonetheless, they are interesting animals. The diversity of morphology and lifestyle we see in the intertidal snails makes them eminently worthy of study and appreciation. I like to think that, as biologists once again "discover" the usefulness of natural history, students will be encouraged to fill in some of the gaps in our understanding of these and other abundant animals.

It never really feels like springtime until the swallows have returned to the marine lab. This year the barn swallows (Hirundo rustica) came back right on schedule in the last week of March. They have been flying around ever since. I've seen them gathering mud on the banks of Younger Lagoon, but they haven't been very serious about nest building. The cliff swallows (Petrochelidon pyrrhonota), on the other hand, were late arrivals, and I was beginning to worry about them. I didn't see the first cliff swallow until the 1st of May.

Unlike the barn swallows, the cliff swallows immediately started spackling mud on the buildings. There have been a few aborted attempts, but overall they have been very busy little birds. I've been keeping an eye on one nest in particular, as it seems to be the one progressing most rapidly. This nest is located on a building that has been used every year, by both barn swallows and cliff swallows. In previous years I've seen and photographed the nests side-by-side. There isn't any reason to expect them not to nest together again.

So here's what has been going on so far.

The first stage is a simple shelf of mud. The birds are building on vertical walls, but corners where they can use two walls are prime locations. Even a tiny ledge can be used to support those first splats of mud, and once the mud dries it becomes foundation for additional layers. See the mud in the swallow's beak?

Sometimes the birds get this far and then decide to abandon the nest. And sometimes they keep going. Here's what's going on less than a meter away from this nest.

Four cliff swallows building mud nests on wooden walls
Cliff swallows (Petrochelidon pyrrhonota)
2021-05-07
© Allison J. Gong

Notice how the birds use their tails as braces so they can cling onto vertical walls. Woodpeckers do the same thing. Of the four birds in the photo above, the two outer ones look like they're just starting to build. I've seen two birds flying in and out of that larger nest, but have no idea whether or not they're the same two birds every time. I suspect they are a mated pair.

The cliff swallow's nest is the gourd-shaped one, with a body that narrows to a much smaller opening just big enough for one bird to pass through. When the nest I was watching got to the stage in the photo above, I thought the opening would be on the left, since there's already a nice curve along that side of the front edge.

I might be kind of right. Today the opening is much narrower, and located off-center towards the left.

Cliff swallow nest on wooden walls
Cliff swallow (Petrochelidon pyrrhonota) nest
2021-05-09
© Allison J. Gong

This nest may be finished tomorrow or the next day. It will have taken the birds about a week from start to finish.

Why are there no birds near the nest, you may ask? Well, when I walked out of the building I noticed that all of the swallows were in the air, and nobody was at the nest site. The birds were making alarm calls and flying around, but it didn't look like they were feeding, and none were returning to the nests even for short visits. I looked around and up and found the reason for the swallows' unrest.

Red-tailed hawk (Buteo jamaicensis)
2021-05-09
© Allison J. Gong

The hawk was perched directly across from the swallows' nest site, and the swallows were not happy about it.

(For some reason the embedded video isn't working right now. You can watch it from YouTube directly by clicking on that link in the lower left corner.)

Some of the swallows flying around the hawk were barn swallows. I think they are nesting in the breezeway of the building under the hawk. Anyway, the hawk's presence was obviously upsetting to all of the swallows. It hung out for about 10 minutes and then flew away over the field. And immediately, the cliff swallows got right back down to the important business of building a home for the next generation.

A few weeks ago I went out to Franklin Point and saw that the sea lettuces (Ulva sp.) were spawning in the high pools. I revisited the site today, with a lower tide to work with, and spent a considerable amount of time looking for and photographing the staurozoans. I did find some, too! But they are not the focus of this post.

As the tide came back in, I spent more time working my way through the higher pools. At Franklin Point there are very few places where the water is still. Even in the high regions the intertidal terrain is more surge channels than pools. But if you go high enough up the beach there are some quiet areas where the water, if it moves, does so very slowly. It is in these areas where the algal spawn forms those beautiful patterns that I photographed at the beginning of the month. Today there was much less algal spawn accumulating in the calm areas. It was also windy (and cold) this morning, so the patterns were not as crisp as they had been in early April. Still pretty, though!

Algal spawn on surface of a tidepool
Ulva spawn on surface of tidepool at Franklin Point
2021-04-29
© Allison J. Gong

On my way back up the beach I saw something that looked like an iceberg viewed from the air.

Foam on surface of water
2021-04-29
© Allison J. Gong

This is an accumulation of foam being pushed ashore. I didn't have any way to collect a sample to bring back to the lab for closer observation, but foams like this are usually due to algal particulates. Surface agitation whips up the organic matter, which act as surfactants and produce tiny bubbles. I'd be willing to bet that the Ulva spawn is at least partly responsible for this foam.

I watched the foam for several minutes, and was rewarded for my vigilance. I found an area where the highest reach of the incoming tide was gently washing back and forth.

I found the slow swirling to be rather mesmerizing. Maybe that was due to the early morning, the brisk sea air, or hunger pangs. But when I saw this I thought to myself, "I've seen that somewhere before." You might be able to guess where.

Swirling foam on the surface of the water at Franklin Point
2021-04-29
© Allison J. Gong

To validate my intuition, when I got home I looked up some images and found that I was sort of right after all.

The Starry Night by Vincent van Gogh, 1889
Public domain - Google Art Project

Okay, so maybe the resemblance isn't as strong as all that. But I can still imagine the streams in van Gogh's painting swirling and flowing the way the algal foam does. What do you think?

3

Way back in 2015 I wrote about some Ulva that spawned in a bowl at the lab, and delved into the mysteries of reproduction in the green algae. This morning I was out at Franklin Point and saw this:

Spawning algae at Franklin Point
2021-04-01
© Allison J. Gong

I had seen the sea lettuces (Ulva spp.) spawning in these high pools at Franklin Point before, and usually cursed the murkiness of the water. But today the water was dead calm, with the tide low enough that there were no waves to slosh into the pools. The result was a gorgeous marbled swirl in the water. The patterns were stunning.

Yellow streams of algal spawn in a shallow tidepool
Spawning algae at Franklin Point
2021-04-01
© Allison J. Gong
Yellow streams of algal spawn in a shallow tidepool
Spawning algae at Franklin Point
2021-04-01
© Allison J. Gong
Yellow streams of algal spawn in a shallow tidepool
Spawning algae at Franklin Point
2021-04-01
© Allison J. Gong

What these photos show is the Ulva releasing either spores or gametes. Without microscopic examination it's impossible for me to know whether these tiny cells are spores or gametes. What I can say is that the spawn is released from the distal ends of the thallus, making the body of the alga look ragged.

Sea lettuce in a tidepool. Some blades are clear.
Sea lettuce (Ulva sp.) at the edge of a tidepool at Franklin Point
2021-04-01
© Allison J. Gong

The parts of the thallus that have already spawned are now clear. The tissue itself will soon disintegrate, leaving behind only the healthy green parts, which should be able to regrow.

All of these photos were taken in pools where the spawning itself had either completely or mostly stopped. Obviously when the tide comes back all of this yellow spooge will get mixed up. It's only when the water is perfectly still that these streams would form. It was hard stepping around the pools to take the photos, as the last thing I wanted to do was stomp my big booted foot into a pool and disrupt the beautiful patterns. Fortunately the sun angle was a little cooperative this morning, and I was able to find a pool where active spawning was happening.

What appears to be an act of destruction—the alga's brilliant green thallus being reduced to yellow streaks that drift away with the tide—is really an act of procreation. This is terminal reproduction, literally the last thing an organism does before it dies. Salmon do this, as do annual plants. The sheer amount of algal spawn in these tidepools is astounding. Imagine the number of 2-micron cells needed to color the water to this degree. But if reproducing is the last thing you're going to do in your life, you might as well go all in on your way out, right?

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