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This week was my spring break, and although I have more than enough work to catch up on, I decided that each day I would spend a few hours doing something fun before or after getting stuck in with adult responsibilities. I didn't set up formal plans, but knew I wanted to collect a plankton sample early in the week. Monday 21 March 2022 was the vernal equinox, which seemed as good a time as any to see what was going on in the plankton.

And the plankton was quite lively! I was very pleased to see a lot of diatoms in the sample. Diatoms are early season bloomers, able to take advantage of nutrient inputs due to coastal upwelling. They are usually the most abundant phytoplankters from about March through July.

Mixed marine plankton
Mixed plankton sample, collected from the Santa Cruz Municipal Wharf
2022-03-21
© Allison J. Gong

All of those button-like round objects are centric diatoms in the genus Coscinodiscus. They can be large cells, getting up to 500 μm in diameter. Coscinodiscus is in some ways the quintessential centric diatom, as you will see below.

Take a look at these objects:

Clearly, one is a circle and one is a rectangle, right? Well, yes, but these two objects are the same type of thing—they are both cells of Coscinodiscus. The easiest way to understand diatom anatomy is to think of the frustule (the outer skeleton of the cell) of Coscinodiscus as being constructed like a petri dish. Because that's actually what it is: an outer casing of silica with two halves, one of which fits over the other exactly the way a petri dish lid fits over the bottom of the petri dish. If you place a petri dish on a table and look down on it, you will see a circle. But if you pick up the petri dish and look at it from a side view, you will see a rectangle. If you don't believe me, go ahead and try it with any canned food item in your pantry. Coscinodiscus is the same. If it lands on the microscope slide lying flat, it will look like a circle; this is called the valve view because you are looking down on the surface of one of the two valves of the frustule. Most of time when we see Coscinodiscus we see it in valve view. Sometimes you get lucky and a cell remains "standing up" even after you drop a cover slip on top of your sample, and you see the cell as a rectangle. This is called the girdle view. So in the photo above, what you see on the left is a Coscinodiscus cell in valve view, and what you see on the right is the same type of cell in girdle view. Same object, two perspectives, and two shapes. By the way, this is the answer to the question posed in the previous post.

And this is what a valve view of Coscinodiscus looks like when you zoom in:

Circular object with golden-brown spots
Coscinodiscus sp. under brightfield lighting, showing true colors
2022-03-21
© Allison J. Gong

You can see some of the sculpturing on the frustule, and the beautiful golden-brown color of diatoms. The diatoms are related to the brown algae and share the same overall set of photosynthetic pigments, which explains why diatoms are often the same colors as kelps.

Another of the common diatoms around here are those in the genus Chaetoceros. The prefix 'chaet-' means 'bristle', and the cells of Chaetoceros have long bristles. Unlike Coscinodiscus, Chaetoceros forms chains. Some species form straight chains, others form spiraling chains, and still others form a sort of meandering chain that is embedded in a tiny blob of mucilage. The cells below are forming a straight chain.

Chain of rectangular boxes, each containing amorphous golden blobs. Long bifurcating bristles protrude from the corners of the boxes.
Chaetoceros sp.
2022-03-21
© Allison J. Gong

In addition to all of the diatoms, there were more dinoflagellates than I expected to see. Ceratium was very well represented, often in chains of two cells.

A golden cell with two points at one end and a single point at the other. Three golden ovoid cells in a chain.
Dinoflagellate (Ceratium lineatum, top) and an unidentified diatom
2022-03-21
© Allison J. Gong

I was even able to capture some video of Ceratium cells swimming in the thin film of water under the coverslip. Dinoflagellates have two flagella: one wrapped in that groove, or "waistline", and one that trails free. Usually it's the trailing flagellum that's easier to see, and if you watch you'll be able to see it in each of the cells.

Protoperidinium was another common dinoflagellate in the sample. Unlike the diatoms and photoautotrophic dinoflagellates, which have that sort of golden-brown color, Protoperidinium is a heterotroph. It eats other unicellular protists by extruding its cytoplasm out of the holes in its cellulose skeletal plates and engulfing prey, similar to the way an amoeba feeds. Because it does not rely on photosynthesis for obtaining fixed carbon, Protoperidinium comes in colors that we typically don't associate with photoautotrophs. Pink, red, and grayish brown are common colors. This time I saw several that were bright red.

A disc-shaped object with a single point on one side and two points on the other side. Object contains small red blotches.
Protoperidinium, a heterotrophic dinoflagellate
2022-03-21
© Allison J. Gong

So that's a glimpse of springtime in the ocean. Now let's look up!

Legend has it that the swallows return to San Juan Capistrano every year on March 19, which is St. Joseph's day. I don't pay attention to St. Joseph's day, but I do pay attention to the vernal equinox every year and keep an eye out for the return of our swallows to the marine lab. We get both cliff swallows (Petrochelidon pyrrhonota) and barn swallows (Hirundo rustica) building mud nests on our buildings. Last year (2021) the cliff swallows showed up first, with the barn swallows arriving a few weeks later; I remember being worried that they might not show up at all.

This year the swallows returned right on schedule. I saw my first barn swallows on the day of the vernal equinox, 21 March 2022.

Barn swallow (Hirundo rustica)
2022-03-21
© Allison J. Gong

They are so pretty! I haven't seen any nest-building yet, but did witness what might have been a territorial spat. The bird in the photo above is the one on the left that is retreating in the photo below

Bird perched on a sign
Two barn swallows (Hirundo rustica) expressing a difference of opinion
2022-03-21
© Allison J. Gong

Look at that gorgeous outspread tail! Barn swallows migrate to North America from southern Mexico and Central America. The cliff swallows come all the way from South America; no wonder they're a little late arriving in California! I think they'll show up any day now, and both they and the barn swallows will begin daubing mud above doorways and under the eaves.

Somehow, no matter what else is going on and what the calendar says, it never feels like spring until the swallows are zooming around again. Spring is my favorite season, as there's so much going on, and I begin to feel energized again with the longer days. I have a busy spring teaching schedule and don't know how much time I'll have to do fun things like look at plankton for the hell of it, but will try to slow down often enough to take note of what's happening around me.

At ~05:00h UTC on 15 January 2022, the Hunga Tonga Hunga Ha'apai undersea volcano erupted. The eruption was probably followed by a massive undersea landslide, which set tsunami waves out across the Pacific Ocean. This time translates to ~21:00h PST on Friday 14 January, and for the rest of this entry all times and dates will be reported in California time. The eruption and landslide happened in the early morning in Tonga, which was the previous evening here in California.

I woke up on Saturday 15 January (yesterday, as I write this on the 16th) to reports of tsunami warnings for the entire Pacific coast of North America. The first waves were expected to hit the Monterey Bay area around 07:30h. Knowing that we are in spring tides now and that the low low tide (LLT) would be at 15:35h, I back-calculated the preceding high tide (the high high tide, or HHT, for the day) to be around 08:30h. Hmm. High tide plus tsunami surge could equal interesting things to see! And yes, as we were warned not to go down to the ocean, I planned to remain above it all and observe from the bluffs.

What the instruments measured

The volcano erupted first, and caused the landslide. When the massive displacement of water occurred in the ocean, it sent pressure waves through both the ocean and the atmosphere. But before that, the volcanic explosion itself created a pressure wave in the atmosphere. And it happens that the barometer in our weather station caught the pressure anomaly! At 04:04h on 15 January, about seven hours after the eruption, the weather station measured a spike in atmospheric pressure (circled in red in the bottom panel). Our weather station records pressure only every five minutes, so the actual spike may be a bit higher than what was recorded.

Spike in atmospheric pressure, measured by home weather station
Spike in atmospheric pressure, measured by our weather station in Santa Cruz, CA

The National Oceanographic and Atmospheric Administration (NOAA) has tsunami stations established on the entire coast of the U.S., as well as earthquake monitoring stations elsewhere along the Pacific ring of fire. The tsunami station at Monterey measured sea level anomalies due to the tsunami waves striking the coast, starting at about 07:00h, as seen below.

This kind of chart is a little different from what you're probably used to, so let me explain what it shows. You have time and date along the X-axis. The blue line, which is hard to see because it is mostly obscured by the red line, is the predicted sea level; note that it follows the usual trajectory for the tides we have in this area, with two high tides and two low tides every day. The jagged red line is the interesting part. It shows the anomalies, or how the actual sea level deviates from the predicted sea level. There are both positive and negative anomalies. These anomalies are the tsunami surges that hit the monitoring buoy. Positive anomalies are the pressure waves striking the buoy (i.e., the crests of the wave), and negative anomalies are the pauses between surges, or the troughs of the wave. The first large anomaly was about 0.7 meters above the predicted sea level.

Imagine tossing a pebble into a calm pond. When the rock hits the water it sets up a series of pressure waves that emanate in all directions from the point of impact. If you watch those waves, or ripples, you notice that over time they diminish in size until eventually you don't see them anymore.

A tsunami is a similar phenomenon, only ginormously magnified. The underwater landslide displaces a huge amount of water, which then surges away in all directions. These tsunamis travel across thousands of kilometers of open ocean, where they may not make much difference in sea level. But as they approach land they behave like other waves do: they slow down and get taller. When they hit the continental shelf, they surge up coastal waterways and flood any low-lying land they encounter.

And there isn't only one surge. As you can see in the NOAA chart, surges and relaxations occurred throughout the entire day. The purple line indicates the same anomalies as the red line, only they are shown on a single horizontal line instead of on the wave of the blue line. This makes it easier to see how the magnitude of the deviations decreases over time.

What I saw

Double-checking the NOAA tide chart for Santa Cruz, I saw that the HHT would be +1.7 meters at 07:59h. I managed to get myself down to the marine lab, do my chores, and scurry out to Younger Lagoon at about 08:45h. Don't worry, I didn't have time to go down onto the beach, but watched events from the bluff, where I had a better view anyway. Remember, we had a high tide coinciding with the oncoming tsunami surge, so the potential was there for something interesting to happen. Now, a +1.7 meter (= 5.5 feet) isn't an extremely high tide. But combined with a tsunami surge, maybe that would be enough to flow over the sand berm into the lagoon.

And that's what happened. From my position on the bluff I recorded this video:

And here's my nature journal entry:

© Allison J. Gong

Things were pretty exciting at the Santa Cruz Small Craft Harbor, too. All day, people were recording the tsunami surges as they rushed up the harbor from Monterey Bay. Unlike the tsunami in 2011, which tore up both docks and boats, causing extensive damage, yesterday's tsunami was quite mild. I had already made plans for the day and didn't get down to the harbor to check out the action until late in the afternoon. My friend, Murray, built a little boat, Scherzo, who lives in the upper harbor. Scherzo didn't exist in 2011 so we don't know how she would have weathered things. She was floating happily when we went to see her yesterday, although she did seem to be sitting rather low in the water. She probably took on water over her transom during the biggest tsunami surges.

Scherzo is the sleek little craft on the near side of this dock. She is blue with a white cover.

Murray's little boat, Scherzo, in her slip at the Santa Cruz Small Craft Harbor
2022-01-15
© Allison J. Gong

The harbor patrol had blocked access to the docks so they could inspect them for structural damage. I assume, but don't know for sure, that slip renters were able to check on their boats today.

We were at the harbor at 16:30h yesterday. Sea level was still noticeably rising and falling, and even a minute of watching was rewarded with fairly drastic changes. Since we were not allowed onto the docks I was unable to record good footage of how quickly water was moving in the main channel. However, in the side channel where Scherzo is tied up we could watch the water drain. In this video, keep an eye on that rock that looks like a shark fin, near the middle of the frame.

What other people saw

In one of those inevitable consequences of any public safety announcement, the effect of a tsunami warning is to attract people to the beach. I know that many surfers headed out to surf the tsunami, and a lot of people recorded the tsunami from bridges and other places. Here are just a few of the YouTube videos showing the tsunami in the Santa Cruz area.

Video #1: Drone footage of the tsunami pushing into the mouth of the harbor and up the main channel. You can clearly see the green water from Monterey Bay pushing its way through the muddier water of the harbor itself. And the poor dredge sure did take a beating!


Video #2: Tsunami waves heading up Soquel Creek, which opens to Monterey Bay


Video #3: Cars floating at the upper harbor parking lot. I think a lot of this water came up through the storm drains, rather than flowing from the harbor onto the sidewalk and roadway.


Video #4: This video was shot from the Murray Street bridge, looking south at the lower harbor.


Video #5: This footage was shot at the upper harbor, near the dock where Scherzo lives.

So yeah, things were pretty exciting here. But the important thing to remember is that what was a source of entertainment and mild concern here in California, caused tremendous damage in Tonga and neighboring islands. Volcanic ash is settling over the island to the depth of several centimeters, fouling fresh water supplies. The ash is also clouding the air and darkening the sky. Communications have been disrupted, and it is unknown how many casualties resulted from the eruption and ensuing tsunami. Australia and New Zealand have begun deploying aircraft to assess the damage, but it will be a while before we know how bad things really are. Drinking water does seem to be the most pressing need for Tongans and inhabitants of other affected islands.

I imagine that in the coming days there will be opportunities for us to help those who need it. If you can contribute, please do so.

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.

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The rocky intertidal is coming into its full summer glory right now. The early morning low tides have been spectacular in May, and they'll get better for the remaining few days of the month. This morning I went out to Franklin Point to poke around. Low tide was -1.8 feet (yippee!) at 06:13. And for once the swell was also down, so the ocean seemed very far away from the mid-tidal zone. See?

Intertidal rocks covered with algae and surfgrass
Rocky intertidal at Franklin Point
2021-05-27
© Allison J. Gong

One thing that's nice about Franklin Point is that despite its exposure, especially on the north side of the point, all those boulders provide a lot of protection from the incoming waves. It's amazing how they serve to dissipate the water's energy. Of course, that doesn't prevent the inevitable rise of water in the pools, but at least when it arrives it just floods boots instead of knocking down a distracted marine biologist.

Here's a 20-second video I shot from the same spot.

Just as in any terrestrial habitat, summer is when the photosynthetic organisms come to dominate the rocky intertidal. Even a cursory glance shows that every surface is covered with algae and/or surfgrass. So why not showcase some of these organisms when they look their best?

Fronds of feather boa kelp
Feather boa kelp (Egregia menziesii)
2021-05-27
© Allison J. Gong

In terms of biomass, Egregia is by far the most abundant alga along our intertidal coast. Individual fronds can be 5+ meters long, and several fronds arise from each holdfast. Higher up in the mid tidal zone the Egregia was forming curtains hanging down along vertical faces.

Large stand of feather boa kelp hanging down from rocks in the mid-tidal zone
Feather boa kelp (Egregia menziesii) and other intertidal algae
2021-05-27
© Allison J. Gong

But Egregia does know how to share the spotlight. Here it is posing with a couple of other low tidal denizens:

Egregia menziesii, Laminaria setchellii, and Phyllospadix torreyi
2021-05-27
© Allison J. Gong

That's Egregia on the left, of course. One of the laminarian kelps, Laminaria setchellii, is taking center stage in this shot. When it lives in the subtidal Laminaria setchellii is an understory kelp; it gets to about 1.5 meters tall and can form dense stands. In this species each holdfast gives rise to a single stipe that in turn opens into a wide blade that is deeply divided, as you can see. The surfgrass Phyllospadix torreyi is on the right. There is a lot of surfgrass in the rocky intertidal these days. It's pretty treacherous stuff, too. It's very slippery and likes to cover pools that are deeper than you'd expect. I've learned the hard way that it cannot be trusted at all.

My favorite seaweeds are always the reds. And my favorite of the reds is Erythrophyllum delesserioides, looking so lush and pretty this time of year. It is a low intertidal species, and can be locally abundant. Some years it seems to get beat up and look ratty, but this year it looks great. Here it is, surrounding a couple of Laminaria setchellii.

Leafy red seaweed and a brown kelp
Erythrophyllum delesserioides and Laminaria setchellii
2021-05-27
© Allison J. Gong

Here's a grouping of Erythrophyllum and some other reds. I can see two species of Mazzaella, and of course there are Egregia and Phyllospadix mingled together on the right. So pretty!

 in the rocky intertidal
Mixed assemblage of red algae (Mazzaella flaccida, Mazzaella splendens, and Erythrophyllum delesserioides)
2021-05-27
© Allison J. Gong

When the tide is as low as it was this morning, a marine biologist has a lot of time to explore. I had just about exhausted the batteries in both my camera and my phone and was getting uncomfortably cold when I decided to head in. On the way back I stopped to take a look at the rockweeds, which live in the high intertidal. Franklin Point isn't a hotspot for rockweed abundance or diversity, but I did see this nice thallus of Fucus.

Rockweed (Fucus distichus)
2021-05-27
© Allison J. Gong

Fucus is the seaweed with the bifurcated branch tips. The tips are starting to swell up, which means this thallus is getting ready to spawn. Of all the algae, rockweeds are unusual in that they have what phycologists call an "animal-like" life cycle. They don't have sporophytes or gametophytes. They just have bodies, or thalli. Some thalli are female and some are male. Instead of releasing multiple kinds of spores and whatnot, they release eggs and sperm. The resulting zygote develops as you would expect, only instead of forming a young animal it grows into a baby seaweed.

I do love that olive green color of the rockweeds, which belong to the phylum of brown algae (Ochrophyta). Notice that there's a bit of similarly colored sheetlike seaweed right below the Fucus. That seaweed has the same color, but is in the red algae (Phylum Rhodophyta). Once again, we are reminded that the algae cannot be reliably sorted into phyla based solely on color. Mother Nature can be very tricksy!

So there you have it, my trip report for this morning's excursion to Franklin Point. The tides are excellent for the next several days, and I will be out there for most of them. This is my favorite time of the year.

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.

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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.

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