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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.

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.

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 more 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?

The other day I was on a field trip with a couple of students in the Natural History Club, at Younger Lagoon. We had permission to go down into the lagoon itself, where we chased tiny red mites around rocks in the intertidal without getting caught by waves, observed a very interesting interaction between a coyote and assorted water fowl, and witnessed killdeer mating. Did you know that in killdeer the actual copulation is preceded by about half a minute of massage? Neither did we! The purpose of the field trip, other than merely to be outdoors looking at cool stuff, was to spend some time doing focused nature journaling. As a result I didn't have my big camera with me. But I did have the good binoculars, and got to watch all of the action closely.

Nature journaling should be part of any natural history club. Over the years I have seen an increase in the tendency to equate nature journaling with science illustration or other types of art. This conflation is what causes people to believe that they can't keep a nature journal because they don't produce museum-quality works of art. While I appreciate a beautiful science illustration as much as anybody else, a nature journal serves a completely different purpose. A nature journal's job isn't to be beautiful. Its job is to be informative.

If you were to compare my nature journal entry with a photograph of the site, you would see that my sketch is nowhere near realistic in the sense of looking exactly like the real thing. I've compressed the entire lagoon into a short stretch that I could fit in these two pages. But I think the sketches and notes do convey the fascinating things what we saw that day. And even if I were not familiar with Younger Lagoon, I would be able to look at these pages and remember them. That's the job of a nature journal.

Entry in my nature journal

I returned to Younger Lagoon two days later with the camera in tow, hoping that some of the birds we'd seen on Monday would still be there on Wednesday. In addition to the usual Canada geese and mallards, I hoped to shoot a couple of water birds that I didn't recognize.

Let's start with the obvious:

Three Canada geese in flight
Trio of Canada geese (Branta canadensis) coming in for a landing
2021-03-24
© Allison J. Gong

All told, there were a couple dozen Canada geese, in the water, in the air, and on the sand. They were a noisy bunch, as usual. Except for when the coyote showed up. Read that little story in my nature journal.

Now take a look at these geese:

Gaggle of 12 Canada geese and one greater white-fronted goose swimming in Younger Lagoon
Gaggle of geese
2021-03-24
© Allison J. Gong

See the one goose that doesn't belong? That was the mystery goose I saw on Monday, and was fortunate enough to see again on Wednesday. From the photos in my bird field guide—National Geographic Field Guide to the Birds of North America—I thought it might be a greater white-fronted goose (Anser albifrons), although I couldn't be entirely certain. I knew I hadn't seen one before, but a consultation with Cornell's All About Birds verified the ID. iNaturalist shows only a handful of observations of A. albifrons in the Monterey Bay region. The greater white-fronted goose is a long-distance migrator, breeding on the tundra of the high Arctic and overwintering in California's Sacramento and San Joaquin Valleys and the Gulf coast of Texas and Louisiana.

Canada goose in water, greater white-fronted goose on land with wings outspread
Greater white-fronted goose (Anser albifrons)
2021-03-24
© Allison J. Gong

A third goose, and another winter-only bird, is the snow goose. It is a little bigger than the greater white-fronted goose. While the word "snow" implies white plumage, snow geese also come in a blue form, which is a dark blueish gray with a white head. The blue coloration is due to a single gene, and the allele for blue is incompletely dominant over the allele for white. The blue and white morphs are the same species and interbreed freely. The offspring of a pure blue bird and a pure white bird will be dark, but may have a white belly. Goslings from pure white parents will be white, and those from pure dark parents will be mostly dark but may have some white.

Snow geese (Anser caerulescens)
2021-03-24
© Allison J. Gong

Of the two snow geese in the photo, the one in the front is all white except for the black wing tips of the species, while the one in the back has more dark coloration. In the photo the beak looks dark, but in better light it's as pink as on the bird in the front.

So that's three species of geese. Now whose butts are these?

Duck butts at Younger Lagoon
2021-03-24
© Allison J. Gong

These tails belong to American wigeons (Mareca americana), a male and female pair in the background and a lone male in the foreground. As you might guess from the behavior, wigeons are dabbling ducks, foraging on aquatic vegetation. Like the greater white-fronted goose and snow goose, these are also winter visitors to California's waterways, and will soon be headed north.

In their winter plumage, the wigeons are rather dull. The breeding male has a brilliant green patch extending backwards from his eye and a broad white streak from the top of the bill over his head. During the winter the green patch becomes is much less conspicuous, although the white streak remains.

Trio of wigeons, with their tails sticking up out of the water
American wigeon (Mareca americana)
2021-03-24
© Allison J. Gong

Three species of waterfowl. I couldn't get the snow geese to cooperate and make up the quartet.

Greater white-fronted goose, American wigeon, and Canada goose
Left to right: greater white-fronted goose (Anser albifrons), American wigeon (Mareca americana), and a pair of Canada geese (Branta canadensis)
2021-03-24
© Allison J. Gong

Living as we do along the Pacific flyway, we find that spring and autumn are great times for watching birds as they migrate between summer breeding grounds and wherever they overwinter. Sometimes I think it's rather unfortunate that I don't get to see these birds in the glory of their breeding plumage, but that's okay because I get to see them in the winter. And the birds that left here for the winter are returning: I saw the first barn swallow of the season right after the vernal equinox! Soon they and the cliff swallows will be building their nests on the buildings at the marine lab. At home, the first of the season's hooded orioles flew past the back deck. He may have been on his way to a nesting site in a palm tree down the street. There is so much going on right now. I do love the spring!

Intact shells are a limited resource in the rocky intertidal. Snails, of course, build and live in their shells for the duration of their lives. A snail's body is attached to its shell, so until it dies it is the sole proprietor of the shell. Once the snail dies, though, its shell goes on the market to whoever manages to claim it. Empty shells tend not to remain on the market for long.

Hermit crabs also live inside snail shells. They are the ones that compete for empty shells when they do become available. Here in California, at least, the hermit crabs can't kill snails for their shells; they have to wait for a snail to die. And once a shell comes on the market, it will have a taker even if it's not the ideal size for the crab. It's not at all uncommon to see hermit crabs that can fit only their abdomen into the shell, leaving the head and legs exposed and vulnerable. On the other end of the spectrum, many hermit crabs are so small that they can pull into the shell and not be seen by an inquisitive tidepool visitor. Anybody taking a snail shell home as a souvenir—where such takes are allowed, of course—must be certain that there is no tiny hermit crab hiding deep in the depths.

Hermit crab in black turban snail shell
Hermit crab (Pagurus samuelis) in shell of turban snail (Tegula funebralis) at Point Piños
2015-05-09
© Allison J. Gong

From a hermit crab's perspective, the best shell is one that is big enough to retreat into but light enough to be carried around. Snail shells come in a variety of shapes and corresponding internal volumes. Turban snails, with their roughly spherical shape, have a large interior space and are coveted by larger hermit crabs. For example, the grainy hand hermit crab (Pagurus granosimanus) seems to really like both black and brown turban snail shells.

Original inhabitant and builder of the shell:

Brown turban snail partially withdrawn into shell
Brown turban snail (Tegula brunnea) at Pistachio Beach
2021-02-09
© Allison J. Gong

And opportunistic second inhabitant of the same type of shell:

Grainy hand hermit crab in turban snail shell
Grainy hand hermit crab (Pagurus granosimanus) in brown turban snail (Tegula funebralis) shell
2018-06-01
© Allison J. Gong

Other snails are not even remotely spherical. Olivella biplicata, for example, is shaped like the pit of an olive. Unlike Tegula, of which both intertidal species are found in rocky areas, O. biplicata burrows in sand. Note the shape and habitat of this olive snail:

Olive snail
Olive snail (Olivella biplicata) burrowing through sand at Whaler's Cove
2019-11-24
© Allison J. Gong

These olive snails have a smaller internal volume, and thus tend to house smaller hermit crabs. Young individuals of P. granosimanus can be found in olive snail shells, but they quickly outgrow the cramped quarters and need to find a larger home. Smaller hermits such as Pagurus hirsutiusculus, though, are often found in olive shells.

Any hermit crab that finds itself robbed of its snail shell has a short life expectancy. The front end of the hermit resembles the front end of any crab, with the familiar armored legs, claws, eyestalks, and antennae. But the abdomen is soft and unarmored, covered by only a thin cuticle. The abdomen is coiled to follow the coiling of the snail shell, which allows the crab's body to curl around the columella, the central axis around which the shell spirals. In this way the crab can hang onto its snail shell and resist a tug by a would-be predator. A strong enough tug, though, will rip the crab's front end (head + thorax) away from its abdomen. So if you ever find yourself with a hermit crab in hand, do not be tempted to remove it from its shell by yanking it out!

The next time you encounter gastropod shells in the tidepools and want to know whether the inhabitant is a snail or a hermit crab, watch to see how it moves. Hermit crabs scuttle, as crabs do, while snails glide along very slowly. You would also notice a difference as you pick up the shell: snails stick to the rock with their foot, which you will feel as a suction. Hermit crabs don't stick at all, so if the shell comes away easily it likely houses a crab instead of a snail. See? Easy peasy lemon squeezy!

Sometimes even a well-known site can present a surprise. Here's an example. Yesterday I went up to Davenport to scope things out and see how the algae were doing. This is the time of year that they start growing back after the winter senescence. I also took my nature journal along, hoping to find a spot to sit and draw for a while.

The first thing I noticed was the amount of sand on the beach. Strong winter storms usually carve sand off the beaches, making them steeper. And during the calmer months of summer the beaches are flatter and less steep. Yesterday the beach was very thick and flat. It makes trudging across the sand in hip boots much easier!

The accumulation of sand meant that I could walk around the first point. Unless the tide is extremely low, such as we see around the solstices, the water is too deep for that. But yesterday I walked around it, and it wasn't until I got to the other side that it occurred to me that: (1) hey, I walked around the point; and (2) I could do that only because there was so much sand. See, a thick beach with a lot of sand makes a mediocre low tide feel lower because the water isn't as deep as it would be if the beach were thinner. When the tide isn't low enough for me to walk around the point, I have to clamber down a cliff. The cliff height varies depending on how much sand has built up, obviously, but is about head height for me. Getting down usually involves scooting on my butt and hoping my feet land on something that isn't slippery. As with most climbing, up is easier and less scary than down.

It's hard to imagine the amount of sand there was yesterday. Look at this picture.

Flat rock area and sandy area
North of Davenport Landing Beach
2021-02-08
© Allison J. Gong

See how the rocks in the foreground end? Usually that's the edge of the cliff. Yesterday I could have just taken a tiny step off the top of the cliff onto sand. That's over 1.5 meters of sand in that one spot! If the couple in the background were visiting this area for the first time, they'd have no idea of the conditions that made it so easy for them to get out onto the reef.

There was a lot of sand in the channels between rocks, too.

Sand between rocks in the intertidal
Intertidal area north of Davenport Landing Beach
2021-02-08
© Allison J. Gong

Normally those channels are deeper. You can see that some anemones were able to reach to the surface of the sand, but many more are buried, along with any other critters and algae unfortunate enough to be attached to the lower vertical surfaces. And while some of them will either suffocate or be scoured off as the sand washes away, many will survive and be ready to get on with life.

The second surprise of the day was a bright orange object. What I could see of it was about as big as my thumb, and at first I thought it was a nudibranch. Then when I crept closer for a better look, what popped into my head was "snailfish". Which was an odd thing, because I'd never seen a snailfish before. But something about the creature's posture looked somehow familiar.

Orange fish with large head and tail wrapped around the body
Tidepool snailfish (Liparis florae) at Davenport Landing
2021-02-08
© Allison J. Gong

Fortunately I had the presence of mind to take photos before trying to draw this little fish, because this is all I had time to get:

When I spooked the critter it took off really fast, confirming that it was no nudibranch. It was, indeed, a snailfish! It came to rest in a small hole in a rock, from where it looked out at me.

Tidepool snailfish (Liparis florae) at Davenport Landing
2021-02-08
© Allison J. Gong

The snailfishes are a very poorly studied group. As a group they are related to the sculpins. There are snailfishes throughout the northern temperate and polar regions, from the intertidal to the deep sea. iNaturalist shows 43 observations of L. florae, eight of which are in California. Before yesterday, none had been recorded at Davenport Landing.

Map of northeast Pacific coast, showing sighting of tidepool snailfish recoreded in iNaturalist
Observations of tidepool snailfish (Liparis florae) recorded in iNaturalist
2021-02-09
© iNaturalist

So there you have it, a snailfish! We don't know much about any of the snailfish species, even the intertidal ones. They apparently have pelvic fins modified to from a sucker, similar to the clingfishes, but I didn't have a chance to examine this specimen closely enough to confirm that. I don't know why they are called snailfishes, either. They're not snail-shaped at all.

Now, about that thing up there where I said "snailfish" came to mind even though I'd never seen one before. That happens quite a bit—a name will jump into my head before I've had a chance to think about it. Sometimes I'm wrong, but often I'm right. I know I hadn't seen a live snailfish before, but obviously I'd seen photos of them or I wouldn't have been able to recognize this orange creature as being one. It's fascinating how the brain forms search images, isn't it?

During what has become my daily check to see what's going on in Younger Lagoon, I got totally lucky and was able to see and photograph lots of birds. A morning with mostly cloudy skies meant good light for picture-taking. So I took lots of pictures! Some of these are series and need to be viewed in order to see the action. Sure, I could have just shot videos, but where's the fun in that? Sometimes still photos show a lot more than video.

It was a great day to watch wading birds! Legs and beaks come in varying lengths, and a particular species' combination of beak length and leg length determine where and how the bird forages.

Long-billed curlews, snowy egret, and marbled godwit on the beach at Younger Lagoon
Shorebirds at Younger Lagoon. Left to right: Two Long-billed curlews (Numenius americanus); snowy egret (Egretta thula); long-billed curlew; marbled godwit (Limosa fedoa)
2021-01-30
© Allison J. Gong

While the long-billed curlew (N. americanus) has the longest beak-length-to-head ratio of any bird, the marbled godwit and whimbrel also have impressively long bills. In the photo below, the three birds with slightly downcurved beaks are whimbrels (Numenius phaeopus) and the one bird with the two-toned straight beak is the godwit (Limosa fedoa). Most of the godwits I've seen have beaks that are a smidge upturned, but this one looks pretty straight to me.

Whimbrels and marbled godwits in the surf zone at Younger Lagoon
Shorebirds at Younger Lagoon. Three whimbrels (Numenius phaeopus) with downcurved beaks and one marbled godwit (Limosa fedoa) with straight beak
2021-01-30
© Allison J. Gong

All of these birds forage by probing the sand with their beaks. All sorts of infaunal invertebrates are taken, and the mole crab Emerita analoga is a favored prey item. Obviously a longer beak allows for deeper probing in the sand, and the variation in beak lengths among the shorebird species may allow for niche partitioning. In other words, a long-billed curlew can reach down for prey items that are unavailable for birds with shorter beaks. The flip side of this equation is that birds with the "short" beaks might be better at picking up prey buried that are buried at shallow depths.

Prey are also distributed patchily along the beach itself, from the surf zone to the dunes, and these birds forage in the entire range. The length of the legs determines how far down into the surf zone they can go. When the beach is steep, as it is now at Younger Lagoon, the birds don't have much time to dig around in the surf zone before the next wave comes up. Click through the slide show to see this group of godwits, curlews, whimbrels, and a snowy egret react to an oncoming wave. It's important to note that while these birds do have some waterproofing in their feathers, they do not swim. Nor can they take flight if their feet aren't on the ground. Getting swept up by a wave and carried off the beach would likely be deadly for them.

The long-billed curlew is a favorite of mine, because I can't imagine what it would be like to go through life with a 2-meter beak sticking out of my face. They are fun to watch, and can probe remarkably fast with that long beak. This is one of the phenomena that is best shown by video.

You can watch how the birds forage within the surf zone, as in the slide show above, and also how long-billed curlews probe the sand higher up the beach.

Shorebirds foraging at Younger Lagoon
2021-01-30
© Allison J. Gong

These long-legged wading birds also feed in protected bodies of water and estuaries. All of these species can be seen at Elkhorn Slough as well as on the open coast, as one would expect from the Slough's position along the Pacific Flyway. Some birds migrate to California from far away. Marbled godwits, for example, spend the summer breeding season in the interior regions of North America, and winter along the Pacific, Gulf of Mexico, and Atlantic coasts. The long-billed curlew also breeds in the interior of the continent. Snowy egrets, on the other hand, are year-round residents.

I am grateful to have access to places like Younger Lagoon, where I can spend time outdoors without other people around, remove my mask, and take pictures of birds. I love that the Younger Lagoon Reserve has so many different habitats to explore, from ocean to beach to dunes to coastal scrub, in a small area. Fingers crossed that sooner rather than later, we'll be able to once again bring students there to study the natural world in the Reserve's outdoor classrooms.

In terms of weather, this has been the first real week of winter we've had so far this season. But finally we're getting some action from an atmospheric river, and it is bringing both much-needed rain and the threat of mudslides in mountain regions that were badly burnt just a few months ago.

Graphic showing what atmospheric rivers are and how they affect precipitation

During an El Niño event, the probability of higher-than-average rainfall in California is usually due to what are called Pineapple Express storms. These warm, wet storms occur when the atmospheric river is to the south and picks up and transports water from the tropics. La Niña, which is the counterpart to El Niño, typically results in drier-than-average conditions in California, but when the atmospheric river does come into play it comes from the north and is cold.

We are currently at the mercy of La Niña, and weather forecasters predict these conditions will continue through February and then begin to wane through the early spring. This means that the storms we've had over the past several days have been cold. According to our weather station, on Monday 18 January the high temperature was 24ºC (75ºF), and a week later on Monday 25 January the high was 12ºC (53ºF). It has continued to be chilly throughout the week. Today, Friday 29 January, we're getting a break between storm systems and it's beautifully sunny. Because of the sun it feels warmer, but the actual air temperature probably won't get much higher than it has been already this week.

Yesterday we were hit by what was probably the strongest of the storms in this particular atmospheric river. At the marine lab the waves were routinely splashing up and over the cliffs. When that much water crashes into solid land, the pounding is felt as much as it is heard. After doing my chores I wandered over to Younger Lagoon to see what was going on. I wanted to see if the lagoon had broken through the sand bar.

I spent some time watching the ocean, and this is what I saw:

Storm waves at Younger Lagoon
2021-01-28

That sand bar forms as sand accumulates on the beach during the summer, following the typical sand cycle along the California coast. Younger Lagoon does not drain a river, so there is not a constant flow of fresh water down to the ocean. There is some run-off from the surrounding agriculture fields, but the vast majority of water flowing through the lagoon is run-off from rain. It's that heavy flow of fresh water that sometimes breaches the sand bar and allows water from the ocean to mix with water in the lagoon.

Given how much rain we'd had, I thought it likely that the lagoon would have breached. But as you can see from the video above, it had not. Clearly, there hasn't yet been enough fresh water flow through the lagoon to break through the sandbar.

So we're still waiting for that event. I suspect that once it does, we'll know because of the smell.

In the meantime, the ocean continued to pound the coast. I was wearing my foul weather gear so I went to Natural Bridges to watch the waves slam against the rock formations. That was a fun excursion! The big swells were coming in so fast that the deep BOOM-BOOM-BOOM was almost continuous. Close to shore the water was a constant froth of movement.

Storm waves at Natural Bridges
2021-01-28

You can see how high the waves were hitting against the cliff. The mist blew quite far across the parking lot, and I went home with saltwater drying in my hair. Fortunately I got to spend the rest of the day indoors, drinking tea and keeping dry. Winter storms are great fun, as long as you don't have to be out in them!

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