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3

If, like me, you are fortunate enough to live near the coast in Northern California, you get to visit the tidepools. And when you do, you may notice something that looks like a pile of sand in the mid tidal zone below the mussel beds. When you venture down and touch the sand, you'll find that it's hard--hard enough to walk on, if you step very carefully, but also somewhat brittle.

It might look something like this:

Mound of Phragmatopoma californica tubes at Natural Bridges
2017-05-26
© Allison J. Gong

Meet Phragmatopoma californica, the sandcastle worm. Hard to believe that these mounds, which can be the size of a small dining room table, are constructed by little worms, isn't it? Phragmatopoma is one of the many marine segmented worms grouped together as the Polychaeta. We have lots of polychaetes on our coast, ranging in size from greater-than-hand-length nereids and glycerids that can take a bite out of you and draw blood, to tiny worms small enough to swim in the layer of water between sand grains. In fact, the majority of our worm fauna on the coast consists of polychaetes.

Polychaetes make up a large and very diverse taxon, comprising some 80 or so families. Polychaete taxonomists might argue against it, but to make things simpler, we can divide them into two subclasses, the Errantia and the Sedentaria. As the name implies, the Errantia comprises the worms that are errant, or free-crawling. That said, most of them don't actually crawl around in plain sight; they tend to burrow in sediment, shell debris, or gravel, or wiggle their way through various benthic faunal communities. Some of them make temporary shelters by wrapping themselves in pieces of algae sewn shut with mucus threads. The Sedentaria, on the other hand, are pretty much all, well, sedentary. They live in more or less permanent tubes made of various materials, and generally can't live outside of them.

Phragmatopoma is very much a sedentary worm. It lives in a tube that it builds out of sand grains. Yes, this little worm is a mason!

Phragmatopoma californica tubes at Natural Bridges
2017-05-26
© Allison J. Gong

What you see in these mounds is an aggregation of hundreds of individual worms. The mounds do not form by accident or chance. Phragmatopoma has a planktonic larval stage that floats around on ocean currents for some weeks before returning to the shore. The larva is attracted to areas already colonized by members of their species, which it detects by sniffing out the chemical signal of the glue used to create the tubes (more on that below). This phenomenon is called gregarious settlement. If you consider the challenge of being a tiny creature searching the entire coastline for a place to settle and live forever, one big clue as to the suitability of a given location is the presence of conspecific adults. After all, if your parents' generation grew up there, chances are it's a good spot for you to grow up, too.

Each of those holes in the big sandy mound is the entrance to a worm's tube. Tubes might be as long as 15 cm, but the worm itself is much smaller: a whopping big one would be 4 cm long, and most are in the 2-3 cm size range. From this pair of observations I infer that the worms can and do move up and down the tube. They have to move to the open end of the tube to feed, and can withdraw towards the closed end to avoid predators, or seek protection from desiccation.

Feeding tentacles of Phragmatopoma californica at Natural Bridges
2018-06-13
© Allison J. Gong

Phragmatopoma's tube is not a haphazardly constructed object. It is the worm's home for the entirety of its post-larval life, and is constructed to shield its builder/occupant from the mechanical bashing that occurs twice daily as the tide floods and ebbs. As such, it must be strong and able to maintain its structural integrity. Let's take a closer look at an isolated tube under the dissecting scope:

Tube of Phragmatopoma californica
2019-05-16
© Allison J. Gong

The tube itself is made of debris--sand grains, bits of shell, the occasional tiny sea urchin spine--that the worm gathers from its environment. Glandular regions at the worm's anterior region secrete around the body a cylinder of sticky cement that is chemically similar to both spider silk and the byssal threads that mussels use to attach themselves to rocks in the intertidal. The inside of the tube is lined with a chitin-like material. The worm uses tentacles on its head region to collect and sort the 'stones' and glues them to the outside of the lining. There is some degree of selection involved; in the photo above you can see that all of the sand grains are more or less the same size, with none standing out as being conspicuously smaller or larger than the others. Growing worms that are actively building their tubes may be geographically restricted at least partly by the availability sand grains of the right size; if the sand is too fine or too coarse, the worm's either can't or don't live there.

Life inside a tube

Living in a tube may provide significant protection from wave bashing and predators, but does present some challenges as well. One thing that comes to mind is the matter of personal hygiene: What happens to the worm's poop? As we know, the worm lives inside the tube but it not attached to it, and can crawl up and down within it. To understand how it does, we have to review some basics of polychaete anatomy.

The word 'polychaete' comes from Greek ('many bristles') and refers to the fact that these segmented worms have chaetae, or bristles, along the left and right sides of the body. In some worms the segments, including chaetae, are pretty much the same from the anterior end of the body to the posterior end. In others, the segments and chaetae are differentiated from one body region to another. In the case of Phragmatopoma, all you can see sticking out of a tube is the head region, consisting of the slender feeding tentacles and a large disc-shaped structure called an operculum, which made of fused cephalic chaetae and serves as a door to close off the tube when the worm withdraws. Behind the head is a collar region, a series of three adjacent segments that have very stiff chaetae that can be pushed out against the lining of the tube to anchor the body in place. The rest of the body behind the collar is the trunk, which bears smaller chaetae on each segment. The entire epidermis is ciliated, which keeps water flowing around the body.

But what about the poop? As in most vermiform animals, Phragmatopoma's anus is at the posterior end of the body, which is oriented towards the closed end of the tube. How, then, does it defecate without fouling its home? The answer is both simple and ingenious. Phragmatopoma has a long rectum, which is curved to run anteriorly back towards the head. The anus, located at the terminal end of the rectum, discharges fecal pellets about halfway up the length of the body. The ciliary currents of the epidermis then flush the fecal pellets the rest of the way up the tube and out the top.

The skinny cylindrical things in the photo below are Phragmatopoma's fecal pellets!

Phragmatopoma
Tentacles of Phragmatopoma californica extending from tubes at Natural Bridges
2017-05-26
© Allison J. Gong

Gas exchange is another challenge for animals that live within tubes. Aquatic animals exchange respiratory gases with the water that surrounds them, which is easy for animals that live where the water is constantly moving over their bodies. But for tube-dwellers, gas exchange is much more difficult. Phragmatopoma has paired gills on each segment of the trunk region of the body, which greatly increase the surface area for gas exchange. Any gas exchange surface is useless unless it connects with the circulatory system, so blood vessels flow into and out of each gill. Dissolved oxygen diffuses from the water into the blood, and is then circulated throughout the body. A certain amount of gas exchange probably occurs across the surface of the tentacles, too. To make things easier, the ciliated epidermis of the body keeps that small amount of water inside the tube moving, minimizing stagnation. When the worm's head is extended out for feeding, the tube is flushed with clean water. When the worm is withdrawn into the tube at low tide, its only oxygen supply is in the water contained in the tube with it. Like most of its intertidal neighbors, Phragmatopoma hunkers down and waits for the tide to return, when it can feed and breathe more easily.

And speaking of feeding, I should mention that Phragmatopoma is a filter feeder. Those purple tentacles are ciliated and create a water current that brings small suspended particles towards the mouth located at the base of the tentacles. In the video below the operculum is the darker object to the left; it represents the dorsal side of the worm's body. The long, filiform tentacles are the feeding tentacles.

As you may imagine, living in a tube also affects the way that Phragmatopoma reproduces. The worms never leave their tubes, so copulation isn't an option for them. Despite their occurrence in large groups they are not clonal, and reproduce only sexually. Both sexes of Phragmatopoma spawn gametes into the water, where fertilization and larval development take place. Living in dense aggregations and spawning at the same time as everyone else maximizes the chance that egg and sperm of the same species will find each other. Many marine invertebrates throughout the oceans, from corals to sea urchins, spawn synchronously. After all, it does an individual no good to throw gametes out into the world if it is the only one of its type around--all of the metabolic energy that went into producing and maintaining the gametes would be entirely wasted.

Clearly, the advantages of living in a tube outweigh the costs and inconveniences. Phragmatopoma has evolved physiological, anatomical, and behavioral adaptations to deal with life in the intertidal. One of those adaptations is the tube, which solves one set of problems but creates others which also need to be solved if the animal is to survive. Evolution comes up with solutions like this all the time. Every trait has metabolic and/or fitness costs, and an organism's biology is based on this type of evolutionary compromise. Life in the intertidal is a tough game. It is probable that none of the various biological processes that keep Phragmatopoma alive work function quite as well as they could, if they were isolated systems. But inside the bodies of these little worms, everything works just well enough for them to be one of the more conspicuous inhabitants of the intertidal.

I think that's pretty damn cool.

2

In my experience, the most difficult organisms to photograph in the wild are staurozoans. Even birds in flight are easier. The problem with staurozoans is where they live. I never see them in calm, still pools, where taking pictures would be easy. Instead, they seem to like surge channels where the water constantly sloshes back and forth, and even in the few seconds between a wave coming in and receding they never really stop moving. Their bodies are extremely soft and squishy, so the slightest current causes them to flutter and make blurry photos. When they are emersed their bodies don't really look like anything except a soggy booger, so they aren't recognizable as staurozoans unless they are underwater. And when underwater they don't hold still, and so on and so forth.

Still, finding them is always a treat, even if I can't capture photographic proof. They really are extremely gorgeous creatures.

Staurozoan (Haliclystus 'sanjuanensis') at Franklin Point
2019-05-08
© Allison J. Gong

They are also enigmatic creatures. Much of staurozoan biology, including their evolutionary relationships, remains poorly understood. Until recently the staurozoans were considered a subgroup of the Scyphozoa, the taxon that includes the large medusae such as moon jellies (Aurelia spp.) and sea nettles (Chrysaora spp.). However, using data from more extensive morphological and molecular studies, most taxonomists now agree that the Staurozoa should be elevated to a level equivalent to the Scyphozoa. In other words, the staurozoan lineage probably evolved alongside, but separate from, the scyphozoan lineage.

Whatever their evolutionary history and relationships, what we know about staurozoans is very limited. They are considered to be stalked jellies (hence their previously assumed close affinity to the scyphozoans) that do not have a separate polyp stage. Their bodies consist of an adhesive peduncle, or stalk, that attaches to algae or surfgrasses, and a calyx or goblet-shaped portion surrounded by eight tapering arms. Each of the eight arms is topped with a puffball of stinging tentaches which are uses to catch food and presumably to defend the animal against predators. The mouth is located in the center of the calyx, usually lifted up on a short stalk called a manubrium. The animal feeds by capturing prey on the tentacles and flexing the arm so the food is brought to the mouth. Staurozoans are not permanently attached and can sort of 'walk' with a somersault-like motion, flipping end-over-end.

Staurozoan (Haliclystus 'sanjuanensis') at Franklin Point
2019-05-08
© Allison J. Gong
Haliclystus 'sanjuanensis' at Franklin Point
2019-05-08
© Allison J. Gong

Haliclystus 'sanjuanensis' at Franklin Point grows to a length and diameter of ~3 cm, although most of the ones that I see are smaller than that. The most common color is this reddish brown, but I've also seen them in a gorgeous bottle green that makes them much easier to see against the background of their habitat. I usually see them attached to pieces of red algae, but I'm not sure they actually prefer red algae to either green or brown algae. I don't think I've ever seen one attached to a rock.

Last week I had one of those moments in the intertidal when I felt something stuck on my finger and I couldn't get rid of it. That happens frequently, with small bits of algae getting caught on everything; usually I just flick my hand and they go flying off. But this thing wouldn't leave. I finally stuck my hand in the water to rinse it off, and saw that I had been glommed onto by a small staurozoan!

Staurozoan (Haliclystus 'sanjuanensis') on my finger at Franklin Point
2019-05-08
© Allison J. Gong

See how the animal stuck to me with its tentacles, while its peduncle is still attached to a piece of Ulva?

As I mentioned, not much is known about these strange animals. They possess the stinging cells to prove their inclusion within the Cnidaria, but are aberrant medusae which stick to algae instead of swimming around in the water column. Their life cycle is more or less cnidarian-like, but their planula is non-ciliated. Their ecological relationships haven't really been studied at all.

Which is why this photograph is so informative. It's not a great picture, by any means, but it shows a glimpse of how staurozoans interact with other species.

2019-05-08
© Allison J. Gong

This is a picture of two animals, a staurozoan (H. 'sanjuanensis') and a nudibranch (Hermissenda opalescens). Both of these animals are predators. Hermissenda is well known for its affinity for general cnidarian prey, from which it steals the stinging cells to defend its own body (a behavior known as kleptocnidae). But the staurozoan should be quite capable of defending itself. So, who is doing the eating, and who is being eaten?

Given the dastardly nature of Hermissenda, I'd bet on it as the eater. Those damned nudibranchs have to spoil everything! The staurozoan will probably sustain damage, perhaps losing a tuft of tentacles, but should be able to regrow the lost parts. And the sting of the staurozoan may keep the nudibranch from eating as much as it would like. That's the thing. We just don't know.

I'll definitely be keeping an eye out for the staurozoans at Franklin Point the rest of this tide season. I may even bring a few back to the lab for closer inspection; my collecting permit allows me to do so. I could then photograph them under controlled conditions and hopefully get some better pictures. I find these animals very intriguing, being both so clearly cnidarian-like and simultaneously so inscrutable. I always did like a good mystery story!

All semester I've been taking my Ecology students out in the field every Friday. We've visited rivers, forests, natural reserves, endemic habitats, and fish hatcheries--none of which fall into my area of expertise. This year I have several students interested in various aspects of food production, natural/holistic health practices (which sometimes conflict with actual science!), mycology, as well as some who haven't yet decided in which direction to take their academic endeavors. Until very recently I haven't been able to share with my students much of what I really know, which is marine biology. I did have them learn the organisms that live on docks at the harbor, but that was to study the process of ecological succession rather than natural history.

Yesterday, finally, I took the class into my real field, the rocky intertidal. This year it happened that the best Friday to do our annual LiMPETS monitoring was at the end of the semester. We welcomed the new regional LiMPETS coordinator, Hannah, to our classroom on Thursday for some training. Students learned about the history of the LiMPETS program, some natural history of the rocky intertidal in California, and got to practice some organism IDs with photo quadrats of actual intertidal areas.

The real fun, of course, occurs in the field where the organisms live. So we went here:

LiMPETS monitoring at Davenport Landing
2019-05-10
© Allison J. Gong
Sampling along the vertical transect
2019-05-10
© Allison J. Gong

We didn't have a very good student turnout, unfortunately, but the ones who did show up were diligent workers and we got everything finished that Hannah needed. Most of the time was spent sampling along the permanent vertical transect line. This line is sampled at 3-meter increments along a line that runs from the high intertidal into the low. The same quadrats are sampled every time, and the data collected are used to determine how specific sites change over time. The most difficult part of the monitoring is finding the eye bolts that mark where the transects begin!

Sampling along the vertical transect
2019-05-10
© Allison J. Gong

I admit, I was a little bummed at the low turnout and late arrival of my students. But the intertidal is the intertidal, and it didn't take long for me to adjust my attitude. I worked up a handful of quadrats with Hannah, then let the students do the bulk of the heavy lifting. This was their field trip, after all. So I wandered around a bit, remaining within hearing distance in case I was needed. I needed to find some stuff!

I just want to show some of the animals and algae in the intertidal yesterday. I didn't realize how much I missed this basic natural history stuff until I got to spend some time simply looking at things.

Such rich life to see! One of the students was astounded when she learned that we could visit sites like this only a few days each month. "At dinnertime today the spot where you're standing will be under several feet of water!" I told her. Mind blown.

Intertidal biota at Davenport Landing
2019-05-10
© Allison J. Gong

Looking more closely, there were, as usual, interesting zonation patterns to observe. One was the restriction of large brown algae to the vertical faces of rocky outcroppings.

The kelp Laminaria setchellii at Davenport Landing
2019-05-10
© Allison J. Gong

In the mid-intertidal, mussels (Mytilus californianus) rule the roost. They are often (but not always) accompanied by gooseneck barnacles (Pollicipes polymerus). The barnacles, for reasons discussed in this earlier post, always live in clumps and are most abundant in the lower half of the mid-intertidal mussel beds.

Gooseneck barnacles (Pollicipes polymerus) and mussels (Mytilus californianus) at Davenport Landing
2019-05-10
© Allison J. Gong

During the training session on Thursday, Hannah told the students that Pollicipes is easily identifiable because the barnacles look like dragon toes. I think I can sort of see that. They are scaly and strange enough to be dragon toes.

Gooseneck barnacles (Pollicipes polymerus) at Davenport Landing
2019-05-10
© Allison J. Gong

The algae are taking off now, and the site is starting to look very lush.

Mishmash of algae at Davenport Landing
2019-05-10
© Allison J. Gong

Even algae start as babies! These balloon-shaped things are young Halosaccion glandiforme thalli, surrounded by other red algae. The large blades belong to Mazzaella flaccida, which makes up a large portion of algal biomass in the mid-intertidal zone.

Halosaccion glandiforme and Mazzaella flaccida at Davenport Landing
2019-05-10
© Allison J. Gong

The tidepools at Davenport Landing are good places to see fish, if you have the patience to sit still for a while and watch. This woolly sculpin (Clinocottus analis) posed nicely in the perfect pool for photography--deep enough to submerge the camera, with clear, still water.

Woolly sculpin (Clinocottus analis) and purple urchins (Strongylocentrotus purpuratus) at Davenport Landing
2019-05-10
© Allison J. Gong

And I was finally able to take a good underwater shot of a turban snail carrying some slipper shells. I've already written about the story of this gastropod trio in case you need a refresher. I'm still waiting to see a taller stack of slipper shells some day.

Black turban snail (Tegula funebralis) with slipper shells (Crepidula adunca) at Davenport Landing
2019-05-10
© Allison J. Gong

It was impossible not to feel satisfied after spending some time looking at these creatures. My attitude was mercifully adjusted, and we all departed feeling that we'd done a good morning's work. Our small group of students was able to collect a full set of data for Hannah. That ended up being a very important accomplishment, as Hannah doesn't have any other groups monitoring at Davenport this spring. This means that our data will probably be the only data collected this year at this site. I'm glad the tide and weather conditions allowed us to stay out there as long as we did.

1

I don't remember what I expected from my first view of Death Valley. I knew it to contain the lowest elevation (Badwater Basin, 282 feet below sea level) in North America and that it was really hot in the summer, but beyond that I had no clue. [Aside: the marine biologist in me wondered which metric 'sea level' refers to, and decided that it was probably mean low low water] I certainly wasn't prepared for the spectacular geology, although in retrospect I shouldn't have been so surprised. We didn't see much in the way of wildflowers, for one reason that I didn't anticipate but which makes perfect sense: although Death Valley received enough winter rain to form a temporary lake in the valley, there hadn't been enough rain in the autumn to trigger a superbloom. That was fine by me, as I'd already seen many wildflowers on the trip and was happy to be fascinated by the geology.

The Road to Nowhere
2019-03-28
© Allison J. Gong

There are at least two small waterways in Death Valley National Park that are called Salt Creek. The first one we encountered was in the hills above the valley, and is a rare desert riparian area.

Salt Creek oasis in Death Valley National Park
2019-03-28
© Allison J. Gong

This Salt Creek is fed by several small natural springs and runoff from the scant winter rains. As you can imagine, this oasis is a vital necessity for wildlife. Animals as large as desert bighorn sheep and as small as quail depend on this water source, which may contain the only somewhat reliable drinking water for 15 square miles.

As I mentioned, for me, Death Valley ended up being all about geology. I knew the valley floor was where we would find the lowest elevation in North America: Badwater Basin, 282 feet (86 m) below sea level. And now I can say that I've seen it, but there isn't much to see except the line of other tourists hiking out across the salt flats to take photos of the sign. So as a must-see destination, Badwater was interesting but not compelling. We skipped it.

But the rocks! The hills surrounding the valley, especially those on the eastern side, are spectacular. My favorite area was a range of hills called Artists Palette, viewable from a gorgeous 1-way loop drive off of Highway 190. When I saw the name on the map I thought it must be a place either a location where painters found minerals they could use to make paint, or a scene they liked to paint. Fortunately we decided to take the detour that meanders through the formations, so we could get off the main road and just gawk. I had never seen anything like this scenery. I know enough geology to understand that minerals come in all sorts of colors, but had not seen them together like this in a natural state. My eye is always drawn to colors, and I couldn't stop goggling at the variety of umbers, ochres, greens, and pinks, all jumbled together like some giant's ice cream sundae.

Approaching Artists Palette in Death Valley
2019-03-28
© Allison J. Gong
Approaching Artists Palette in Death Valley
2019-03-28
© Allison J. Gong
Artists Palette in Death Valley
2019-03-28
© Allison J. Gong
Artists Palette in Death Valley
2019-03-28
© Allison J. Gong

Artists Palette in Death Valley
2019-03-28
© Allison J. Gong

It's impossible to capture the grandeur of this landscape in a photograph. You really have to see Artists Palette in person to appreciate the vibrant colors of these hills. If you ever go to Death Valley , take the time to drive this little loop. You won't regret it!

Across the valley to the west, are the Panamint mountains. Beyond them, the Owens Valley and the mighty Sierra Nevada!

The Panamint Range, Death Valley
2019-03-28
© Allison J. Gong

So those are the rocks. The fish were in the second Salt Creek that we encountered, about 20 miles north of the Artists Drive loop. This Salt Creek is one of the remnant small bodies of water left after Lake Manly dries up. Lake Manly is a temporary lake that occasionally forms in Badwater Basin after unusual heavy rains. Most of the time, though, Badwater Basin is dry except for some small creeks. Salt Creek generally flows from north to south down the valley and eventually disappears into the sand.

Salt Creek in Death Valley
2019-03-28
© Allison J. Gong

Salt Creek is inhabited by a little pupfish, Cyprinidon salinus salinus, that looks like and is about the size of a guppy. Well, maybe it's a little bigger than a guppy. Populations of pupfish inhabit several creeks scattered over the desert across California and Nevada. Over time they have evolved into 10 genetically distinct species and subspecies, each adapted to the nuances of its particular stream. Two of the 10 have gone extinct in historic times. The Salt Creek pupfish, C. salinus salinus, is endangered, due to the ephemeral nature and fragility of its environment.

Salt Creek pupfish (Cyprinidon salinus salinus) in Death Valley
2019-03-28
© Allison J. Gong

They are called 'pupfish' because they appear to be playing like puppies. Plus, they are very cute. But life as a fish in one of the driest places on the planet is a tough gig. Pupfish live short, intense lives, growing to adulthood and breeding in the span of a single year.

Salt Creek pupfish (Cyprinidon salinus salinus) in Death Valley


As you can see, the creek is hardly deep enough for these little fish to swim. Pupfish exhibit the sexual dimorphism common in fishes--females are rather drab and nondescript, while males are more colorful. The behavior that was described as playful, earning the fish the moniker 'pupfish', is really all about the business of living. Males are territorial, defending a spot against other males. When a female chooses to spawn with a male, she enters his territory. Then the two of them perform a short, wiggling dance, and spawn together.

From the perspective of an evolutionary biologist, the isolated pupfish populations are fascinating. Each waterway inhabited by pupfish is an independent 'island' in a very real sense of the word. The fish cannot migrate between streams, and thus populations evolve independently of each other. This is called allopatric speciation, from the Greek roots 'allo-' meaning 'other' and '-patry' meaning 'country'. Over time, each population becomes reproductively isolated from the others, so that even if Manly Lake were to become once again a permanent body of water, the fish from different streams would be unable to mate with each other.

Of all the things that manage to eke out a living in what is arguably one of the most inhospitable places in the world, these little fish are my favorite. Major props to them, for surviving where they do and making it look like fun!

Joshua Tree National Park gained a certain notoriety this past winter, when idiots went there during the federal government shutdown and trashed the place. The vandals chopped down the iconic Joshua trees (Yucca brevifolia), let their dogs run around unleashed, left litter scattered over the landscape, and carved new roads through the desert. I'd like to give most people the benefit of the doubt and assume that they didn't realize the damage they were doing to the park. However, it takes only a few bad apples to destroy a public resource for everybody, as we've all experienced at some point.

© DesertUSA

The very first thing I learned about Joshua Tree is that it has two distinct desert habitats. Hey, I'm a marine biologist, and the desert--any desert--is new territory for me. None of this landscape has been anywhere near the ocean for millions of years! Anyway, the eastern half of the park is Colorado Desert, which is similar to what we had seen at Anza-Borrego State Park. Many of the plants in this region were also familiar to us because we had seen them in Anza-Borrego, but for the most part were more abundant here in Joshua Tree.

For example, we saw many more bluebells (Phacelia campanularia) at Joshua Tree than in Anza-Borrego. The P. campanularia at Joshua Tree also looked healthier (more robust and vigorous, less spindly) than they did in Anza-Borrego. Perhaps the higher elevation of the Colorado Desert in Joshua Tree (approximately 914 meters, or 3000 feet) compared to Anza-Borrego (182 meters, or 597 feet) accounts for this observation.

Desert bluebells (Phacelia campanularia) at Joshua Tree National Park
2019-03-27
© Allison J. Gong

I really liked the Colorado Desert in Joshua Tree. Even though it was the same ecosystem as what we saw in Anza-Borrego, here the flowers seemed more colorful and striking. The yellows were a little brighter, and the pinks and blues a little deeper. The scenery was breathtaking everywhere I looked. I wish my photos could do justice to the beauty of the landscape.

Wildflowers at Joshua Tree National Park
2019-03-27
© Allison J. Gong

Aside from the desert bluebells, other flowers that we had seen at Anza-Borrego included the brittlebush (Encelia farinosa), which seems to be ubiquitous in the Colorado Desert. The Arizona lupine (Lupinus arizonicus) was also common in Joshua Tree; like the bluebells, these appeared to be more robust here than in Anza-Borrego.

There were new flowers, too. My favorite, which I didn't see a lot of, was this desert globemallow, Sphaeralcea ambigua:

Desert globemallow (Sphaeralcea ambigua) at Joshua Tree National Park
2019-03-27
© Allison J. Gong

Here's a close-up of the same plant. Look at that gorgeous orange color!

Desert mallow (Sphaeralcea ambigua) at Joshua Tree National Park
2019-03-27
© Allison J. Gong

Against the prevailing palette of yellows and purples, this orange really stood out and caught the eye. This plant is also called the apricot mallow, for obvious reasons.

Some other flowers that we saw:

Among all the colorful flowers in the overall landscape, there was this very subtle plant, easily overlooked by eyes accustomed to more brilliant blossoms.

Sand blazing star (Mentzelia involucrata) at Joshua Tree National Park
2019-03-27
© Allison J. Gong

Something that tickled my funny bone was the little chia plant, Salvia columbariae. It looks like a prickly purple pom-pom. Two days in the desert had taught me not to touch things if I didn't know what they were, but I had to know if these blossoms were as pokey as they looked. They weren't!

Chia (Salvia columbariae) at Joshua Tree National Park
2019-03-27
© Allison J. Gong

There are parasitic plants in the desert, too. The red branches in this bush are the desert mistletoe (Phoradendron californicum), a hemiparasite. It drains water and nutrients from its host plant but performs its own photosynthesis.

Desert mistletoe (Phoradendron californicum) at Joshua Tree National Park
2019-03-27
© Allison J. Gong

In Joshua Tree National Park there's an area called the Cholla Cactus Garden. Chollas are cactuses with cylindrical stems, rather than the flat stems of the beavertail or prickly pear cactuses. The most common one in the Colorado Desert (that we saw, at least) was the teddybear cholla, Cylindropuntia bigelovii. As the name implies, it's a cute, fluffy cactus, but it's definitely still a cactus.

Teddybear chollas (Cylindropuntia bigelovii) at Joshua Tree National Park
2019-03-27
© Allison J. Gong

Teddybear chollas (Cylindropuntia bigelovii) at Joshua Tree National Park
2019-03-27
© Allison J. Gong

The teddybear cactus blooms in May and June, so we didn't see any flowers. In addition to having the normal plant sex using flowers, these cactuses also reproduce clonally by dropping branches. The dropped pieces roll around and find a new place to attach and grow. Interestingly, this type of clonal replication, called budding, is common in many marine invertebrates!

Buds of teddybear cholla (Cylindropuntia bigelovii)
2019-03-27
© Allison J. Gong

Here's a newly detached bud from a teddybear cholla:

Bud of teddybear cholla (Cylindropuntia bigelovii)
2019-03-27
© Allison J. Gong

And here's a recently established, young plant:

Young teddybear cholla (Cylindropuntia bigelovii)
2019-03-27
© Allison J. Gong

Cute little cactus, isn't it?

The trees that give Joshua Tree National Park its name live in the higher and cooler western region of the park, known as the Mojave Desert. The Joshua trees (Yucca brevifolia) live singly or in clusters. In some ways, Y. brevifolia is the symbol of the Mojave Desert. They are also abundant in the higher elevations of the Tehachapi Mountains along Highway 58 between Bakersfield and the town of Mojave.

Joshua trees (Yucca brevifolia) in the Tehachapi Mountains
2017-03-24
© Allison J. Gong

In Joshua Tree National Park, said trees were blooming in late March.

Blooming Joshua tree (Yucca brevifolia) in Joshua Tree National Park
2019-03-27
© Allison J. Gong

I'll have more to say about reproduction in Joshua trees and some other desert plants in another post. This one is getting long, and we had more desert adventures to come.

Next stop: Death Valley

The first new-to-me visit on our spring break road trip was Anza-Borrego State Park in the southern California desert. We arrived late in the day on Monday and had just a brief chance to look around. On Tuesday we got up early and went for a hike, trying to avoid some of the midday heat. Fortunately there was a bit of a breeze, which helped with the heat but made flower picture-taking challenging.

Anza-Borrego is located in the Colorado Desert, which is a western subdivision of the Sonoran Desert. The Colorado is a low-altitude desert (most of the surrounding hills are only ~900 meters tall) and thus gets much hotter in the summer than deserts at higher elevations, and very rarely experiences a winter frost. Winter is the main rainy season and some regions also receive rain during a late-summer monsoon season.

After a rainy winter, the desert explodes into vibrant life:

Anza-Borrego State Park
2019-03-26
© Allison J. Gong

The color of the day at Anza-Borrego was yellow. More details on the yellow players in a bit.

Anza-Borrego State Park
2019-03-26
© Allison J. Gong

It had rained a few days prior to our visit, and there a stream was flowing through the desert.

Anza-Borrego State Park
2019-03-26
© Allison J. Gong

This running water would be a temporary situation, of course, but one that is of great help to the wildlife in the park. At the park visitor center I read that wildlife large and small come to drink from the shallow streams, and that if we were to see bighorn sheep approaching the water we should stay out of their way. Water is so scarce for these animals that any delay in getting to it, or any separation of individuals from their family unit could be very stressful. I didn't know whether or not we'd even see the sheep, since they are shy, but we got lucky!

Desert bighorn sheep (Ovis canadensis) at Anza-Borrego State Park
2019-03-26
© Allison J. Gong

Handsome fellow, isn't he? He was eating and didn't seem to mind us hikers as long as we stayed on the trail. Of course, there was an idiot who approached too close to get a better photo, and this ram wasn't happy about it. He withdrew away from us and then went about his business. Other sheep wandered through, too, to forage or drink from the stream. But this big guy gave me the best photo op.

A visit to the desert this spring, after all the rain we had over the winter, was all about the wildflowers. Most of them were new to me. One thing that struck me was that, instead of the carpets of color that we'd seen at Carrizo Plain or Antelope Valley, flowers at Anzo-Borrega were much more widely dispersed. Some species were very common and others I didn't see more than once or twice.

As I mentioned above, yellow was the predominant color at Anza-Borrego. There were several daisy-like flowers in both yellow and white, and some were very common. Fortunately for me, the visitor center had an easy-to-use pictorial guide of the most common wildflowers; using that, some wildflower field guides that we brought with us, and Calflora.org, I may have identified them all correctly. I'm sure that somebody will point out any identifications that I got wrong.

Brittlebush (Encelia farinosa)
2019-03-26
© Allison J. Gong

One of the defining characteristics of E. farinosa is the way that the blossoms are raised up above the grayish-green foliage. It's a cool morphology, and makes the plant look very different when you see it from the side. Here's a shot that shows it:

Brittlebush (Encelia farinosa)
2019-03-26
© Allison J. Gong

And brittlebush was very abundant!

Lots of brittlebush (Encelia farinosa) at Anza-Borrego State Park
2019-03-26
© Allison J. Gong

Another very abundant yellow flower was the very aptly named desert dandelion, Malacothrix glabrata. It looks like a typical dandelion, perhaps a more pale buttery color than usual, and when mature the blossoms have a small purplish red spot in the center.

Desert dandelion (Malacothrix glabrata) at Anza-Borrego State Park
2019-03-26
© Allison J. Gong
Desert dandelion (Malacothrix glabrata) at Anza-Borrego State Park
2019-03-26
© Allison J. Gong

Our state flower, Eschscholzia californica, is typically a brilliant pure orange color, although sometimes the color can be more yellow. In Anza-Borrego I saw some plants whose foliage looked poppy-ish, but the blossoms didn't look quite right--a little too small to be California poppies and a color that was definitely yellow rather than orange. Turns out, though, that they were gold poppies (E. parishii)!

Gold poppies (Eschscholzia parishii) and one of the purple Phacelia species at Anza-Borrego State Park
2019-03-26
© Allison J. Gong

And who can resist a plant called ghostflower? That palest of yellows, almost but not quite white, combined with the tiny dark speckles, makes the plant seem very quiet--indeed, almost spooky. Ghostflower is easily overlooked, compared to the vibrant yellows of brittlebush, poppies, and dandelions.

Desert ghostflower (Mohavea confertiflora) and gold poppy (Eschscholzia parishii) at Anza-Borrego State Park
2019-03-26
© Allison J. Gong

One of my favorite flower color combinations is yellow, white, and purple. Imagine how pleased I was to find it in the desert!

Desert dandelion (Malacothrix glabrata), desert chicory (Rafinesquia neomexicana) and a purple phacelia (Phacelia distans) at Anza-Borrego State Park
2019-03-26
© Allison J. Gong

The color purple was represented by two species of Phacelia, P. distans and P. campanularia. Phacelia distans was by far the most common in the floors of the valleys, and we saw P. campanularia at higher elevations.

This is Phacelia distans. Note the shape of the inflorescences, and how the blossoms are arranged.

Phacelia distans at Anza-Borrego State Park
2019-02-36
© Allison J. Gong
Phacelia distans at Anza-Borrego State Park
2019-02-36
© Allison J. Gong

And this is Phacelia campanularia, the desert bluebell:

Desert bluebell (Phacelia campanularia) at Anza-Borrego State Park
2019-02-36
© Allison J. Gong

These plants have the same blossom shape, but very different blossom arrangements and foliage morphology. Nifty, the differences between presumably closely related species, eh?

Another flower in the purple family was the desert sand verbena (Abronia villosa). It occurred in sandy soils, often in washes or dunes, similar to the sand verbena that I see on beaches along the coast.

Desert sand verbena (Abronia villosa) at Anza-Borrego State Park
2019-03-26
© Allison J. Gong

The pink color family was represented by the bright pink Bigelow's monkeyflower, Diplacus bigelovii. They were fun. The golden-orange throat is the diagnostic feature for this species.

Bigelow's monkeyflower (Diplacus bigelovii) at Anza-Borrego State Park
2019-03-26
© Allison J. Gong
Bigelow's monkeyflower (Diplacus bigelovii) at Anza-Borrego State Park
2019-03-26
© Allison J. Gong

I didn't get very many good pictures of the white flowers. It always seemed to be especially windy when we saw them. Desert chicory (Rafinesquia neomexicana) is a white daisy-like flower.

Desert chicory (Rafinesquia neomexicana) at Anza-Borrego State Park
2019-03-26
© Allison J. Gong

This being the desert, much of the plant biomass was succulent in nature. The ocotillo were blooming, as were the teddybear cholla and other cactuses.

Ocotillo (Fouquieria splendens) at Anza-Borrego State Park
2019-03-26
© Allison J. Gong

Everything living in the desert survives only if it can take advantage of the minimal precipitation that falls every year. Cactuses must suck up as much water as they can during the wet season, and store it for use during the hot, dry summer. Barrel cactus (Ferocactus acanthodes) this spring are fat, like the barrels for which they are named, and full of water. Their bodies are pleated longitudinally, allowing them to swell up when water is available. Then, as their water stores are depleted during the summer, the pleats fold together and the body becomes more compact. The large saguaro cactuses in the Sonoran Desert do the same thing.

Blooming barrel cactus (Ferocactus acanthodes) at Anza-Borrego State Park
2019-03-26
© Allison J. Gong

A cactus whose blossom definitely belongs in the pink category is the beavertail cactus (Opuntia basilaria). I think it was early in the blooming season for them, as I never saw any plants with more than a few open flowers, but most of them had many buds developing.

Beavertail cactus (Opuntia basilaria) at Anza-Borrego State Park
2019-03-26
© Allison J. Gong

The chollas are cactuses in the genus Cylindropuntia, characterized by cylindrical stems. The teddybear cholla (C. bigelovii) was the one we saw at Anza-Borrego. It has dense spines that give it a fuzzy look but in reality form an impenetrable defense--it manages to say "I'm cute and fuzzy!" and "Don't touch me!" at the same time.

Teddybear cholla (Cylindropuntia bigelovii) at Anza-Borrego State Park
2019-03-26
© Allison J. Gong

The teddybear chollas were very abundant at Anza-Borrego. We continued to see them as we continued on our trip. Next stop, Joshua Tree!

1

We've had a good strong wet season this year, resulting in another wildflower superbloom. Over spring break we went to southern California to chase the flowers and, while we were at it, visit some places that I'd never been to. Our first stops were at familiar stomping grounds that we'd visited in 2017: Shell Creek Road, Carrizo Plain, and Antelope Valley. There were significantly more people at all of these places, compared to two years ago. Many of the well known sites for wildflowers have become very popular lately, and we tried to avoid the most crowded areas.

Location 1: Shell Creek Road

Just because I love the California oaks, here's one that is well festooned with lace lichen (Ramalina menziesii) and moss:

Coastal live oak (Quercus agrifolia)
2019-03-24
© Allison J. Gong

The sky was hazy that day, making for less than ideal picture-taking conditions. The wind certainly didn't help, as the flowers were moving constantly. This early in the bloom the predominant color was yellow: a soft, buttery yellow due to the tidy tips and a much more brilliant, retina-searing gold due to the goldfields.

Goldfields (Lasthenia californica)
2019-03-24
© Allison J. Gong

There was some relief from all the yellow, in patches of baby blue eyes.

Wildflowers along Shell Creek Road
2019-03-24
© Allison J. Gong
Baby blue eyes (Nemophila menziesii)
2019-03-24
© Allison J. Gong

Location 2: Carrizo Plain and Temblor Hills

Soda Lake Road, which runs through Carrizo Plain, was quite crowded. We stopped at the vista point and then headed off the beaten track onto some less-traveled dirt roads.

Still hazy, see?

Soda Lake, from vista point
2019-03-24
© Allison J. Gong

There was such glorious scenery all around!

2019-03-24
© Allison J. Gong
2019-03-24
© Allison J. Gong

To the northeast of Carrizo Plain lie the Temblor Range hills, on which the bloom was just beginning. We saw fiddlenecks and goldfields at lower elevations, and splotches of purple Phacelia and orange poppies higher on the hills.

Fiddlenecks (Amsinckia menziesii), goldfields (Lasthenia californica), and Phacelia ciliata
2019-03-24
© Allison J. Gong

Poppies weren't going very strongly yet, but were distinguishable as a faint orange wash on the hills:

Wildflowers on Temblor Hills
2019-03-24
© Allison J. Gong

We'd see plenty of poppies the next day!

Location 3: Antelope Valley

Antelope Valley was overrun with people, climbing up hillsides with their dogs and selfie sticks. Seems that selfies of people sitting in poppy fields is all the rage these days. We didn't bother even trying to get into the poppy preserve, as there were lots of flowers to be seen in the surrounding areas.

Owl's clover (Castilleja exserta) and California poppy (Eschscholzia californica)
2019-03-25
© Allison J. Gong
California poppies (Eschscholzia californica)
2019-03-25
© Allison J. Gong

Compared to what we saw at Antelope Valley in 2017, this year's bloom was different. This year the poppies were not as widely scattered as in 2017, but where they occurred they were extremely dense. Then again, this year we were early in the bloom, and by now it could be different.

Poppy field at Antelope Valley
2019-03-25
© Allison J. Gong

Next up: Anza-Borrego!

2

The Carmel is a lovely little river. It isn't very long, but in its course it has everything a river should have. It rises in the mountains, and tumbles down a while, runs through shallows, is dammed to make a lake, spills over the dam, crackles among round boulders, wanders lazily under sycamores, spills into pools where trout live, drops in against banks where crayfish live. In the winter it becomes a torrent, a mean little fierce river, and in the summer it is a place for children to wade in and for fishermen to wander in. . . . It's everything a river should be.

-- John Steinbeck, Cannery Row

Every Spring semester when I teach my Ecology class, I try to develop a new field trip activity, or modify an existing one. Some activities I'll probably always keep, either because they are really popular with the students or (more likely 'and') because I think they are good learning experiences, but I can also swap out some of the others if better options come along. There's also some fine-tuning that occurs along the way, as I tweak things to improve what I hope is already a good field trip. As much fun as it is to play outside instead of being stuck in a classroom, the point of the field trips is to learn something about ecology--a new habitat, current research in particular fields of study, challenges to restoration and conservation, and the like. Since citizen science has become the catch phrase du jour in the first fifth of the 21st century, I feel that it is important to give students opportunities to participate in some of the science activities available to the wider community.

The Carmel River
2019-03-15
© Allison J. Gong

All of which explains why the students and I made the hour-long trip down to a location called Garland Ranch, on the Carmel River. Back in the fall I heard of a new project starting up in Monterey County, to monitor water quality along the Carmel River. The project, called Watershed Guardians, is operated from the Pacific Grove Museum of Natural History. Its goal is to protect steelhead trout in the river by measuring parameters that indicate suitability for the various life history stages of the fish. Like many programs of its kind, Watershed Guardians also has a secondary goal of getting students as young as middle-schoolers out of the classroom and into the field to do some real science. The two goals converge quite nicely, as a big part of the learning experience for the students is developing an understanding ownership of their local river and watershed. Hopefully that sense of ownership evolves into one of responsibility and stewardship. And it is a well-known adage that one way to get adults to care about something is to get their kids to care about it first, so all of these citizen science programs directed at school-age children have the benefit of attracting the attention of people old enough to vote and direct policy decisions. Win-win-win!

Our guide for the day was Matt, who works at the PGMNH and led the teacher training session I attended last fall. He met us at Garland Ranch, where we divided the class into four groups. Matt had arrived with two pairs of backpacks, each pair consisting of one light and one dark. The light and dark backpacks contained equipment and kits for different suites of tests. Each group of students would start with one backpack, either light or dark, and then swap with a different group when finished. That way every group ran all of the tests: pH, temperature, turbidity, DO (dissolved oxygen), alkalinity, and salinity. Some of the tests were quite simple, and others were more complicated.

Team 4 conferring with Matt
2019-03-15
© Allison J. Gong

The four sampling sites at the Garland Ranch location were close together near the vehicle bridge. We've had a lot of rain this winter and the river has been running high. As a result a lot of the sand had been washed away, making the beach fairly steep and rather narrow. To make matters even more difficult, the poison oak has been extremely crafty--its bare sticks are everywhere, looking totally innocent, encroaching on trails and twined around trees. It took some attention to make sure I didn't brush up against any of it while moving up and down the beach.

Collecting a water sample
2019-03-15
© Allison J. Gong

Careful sampling requires teamwork!

The final step in the program is for the students to enter their data into the Watershed Guardians database. The whole point of the program is for these data to be shared publicly for all to use. It's important for students to see the activity through to the end and to know that the work they did will actually be going somewhere. We'll take care of that task next week!


Coastal live oak (Quercus agrifolia) at Fort Ord National Monument
2019-03-08
© Allison J. Gong

The other day my students and I lucked out with the weather and managed to get in a full day of exploring a former military base. Fort Ord, on Monterey Bay near the small city of Marina, was an Army base until it was closed in 1994. Since then, most of the land (~14,600 acres) has been designated the Fort Ord National Monument, administered by the federal Bureau of Land Management. Smaller portions were transferred to the surrounding cities, the campus of CSU Monterey Bay, the state park system, and the University of California's Natural Reserve system. Our guide for the day, Joe, is the reserve manager for the Fort Ord Natural Reserve, and had arranged for us to meet with researchers working at both sites that we visited. It really was a fantastic learning opportunity for all of us.

The Fort Ord National Monument (FONM) came into being in 2012--thank you, President Obama! Most of the monument is public land, with miles of trails used to hikers, bicyclists, and horseback riders. The monument is also home to the California tiger salamander (Ambystoma californiense), the central California population of which is federally threatened. The first person we met on our field trip was a guy named Robert, who is a graduate researcher working on conservation of the tiger salamanders. Robert showed us some artificial vernal pools that he's using in his research.

Artificial vernal pools at Fort Ord National Monument
2019-03-08
© Allison J. Gong

The 18 pools are about 10 meters in diameter, lined with an impermeable layer, and were allowed to fill with natural rainwater. Robert's plan is to seed them with salamander larvae and record how they survive and disperse from the pools. There's a lot more to the story than that, but it's Robert's story to tell, not mine.

We did get to help Robert check the pitfall traps, which are arranged in pairs on each side of the fence surrounding each pool. Each trap is a small bucket set into the ground to be level with the surface. The lid is mounted on wooden legs and sits above the trap, to keep it from filling with water. Animals crawling along the fence will fall into the bucket. Robert collects data on the animals trapped and then releases them unharmed.

The tiger salamanders are all underground at this time of year so there were none in the traps. The students did, however, find a pair of western toads (Anaxyrus boreas) in one of the traps. They were in amplexus, which is what herpetologists call the mating position of frogs and toads: the male clasps the female around her body, ideally positioned to fertilize the female's eggs as she lays them.

Western toads (Anaxyrus boreas) at Fort Ord National Monument
2019-03-08
© Allison J. Gong

The pair of amorous toads were released into one of the ponds, where they swam off together, still in amplexus. Their offspring will be born into the pond as tadpoles, along with those of the chorus frogs, the red-legged frogs, and hopefully not too many bullfrogs. Incidentally, herpetologists use the term 'tadpole' to refer only to the larvae of frogs and toads; Robert calls the larvae of his study salamanders just 'larvae'.

We ventured over to the Fort Ord Natural Reserve (FONR), where we ate our lunch in a clearing surrounded by coast live oaks and coastal scrub. FONR is one of five natural reserves managed by UC Santa Cruz as an outdoor classroom and teaching lab. School groups ranging from elementary school to university levels visit FONR to learn about the natural environment, often for the very first time.

FONR sits on an ancient sand dune, and all of the vegetation has had to adapt to difficult growing conditions. The soil is almost entirely sand and doesn't hold water at all. The wind picks up just about every afternoon and blows in salt from the ocean; these winds can be quite fierce even without the salt. The sand itself gets blown around, making an unstable substrate. As a result, plants that would otherwise grow tall are stunted here. Take, for example, the coast live oak (Quercus agrifolia). In places that are more sheltered from the wind, they are tall and majestic, even as they continue their meandering growth form. At FONR they are much shorter and more closely resemble the other scrub plants than actual trees.

Coast live oak (Quercus agrifolia) and coastal scrub at Fort Ord Natural Reserve
2019-03-08
© Allison J. Gon
Horned lizard (Phyronosoma sp.) at FONR 2018-05-12
© Allison J. Gong

After lunch we heard from Dani, a UCSC undergraduate student studying horned lizards (Phrynosoma sp.). The lizards are very well adapted to this environment. They live in sand, and have flattened bodies so they can hide on top of the sand and become practically invisible. Like the tiger salamanders the horned lizards are underground now. They should emerge in the next couple of months. This is one that we saw last May, when Joe invited last year's class to visit the Reserve on a Saturday, after our planned field trip was cancelled due to rain.

Footsteps of spring
Sanicula arctopoides
2019-03-08
© Allison J. Gong

In early March the plants were starting to bloom. One of the earliest bloomers is this delightful plant called 'footsteps of spring'; its real name is Sanicula arctopoides. They look like small blotches of yellow spray paint against the ground. And when you see several of them scattered on the trail, you really understand their common name.

Students follow the footsteps of spring (Sanicula arctopoides)
2019-03-08
© Allison J. Gong

There were, of course, no horned lizards to be seen. We did, however, hike the reserve, and Joe showed us some of the endemic and/or endangered plants that live there. That's Joe, in the front of the group here:

Joe and students
Fort Ord Natural Reserve
2019-03-08

Our last stop at the end of the field trip was at a location where the Army used to work on fire suppression. They did this by dumping various flammable items and fuels on the ground, lighting them on fire, and putting them out. This activity resulted in groundwater and soil contamination, which Army contractors have been working to clean up for 20 years now. Currently the site is where Robert is raising his tiger salamander larvae in raised ponds; he will eventually release the larvae into the artificial pools that we saw earlier in the day.

Ponds for growing salamander larvae
2019-03-08
© Allison J. Gong

Each of those ponds is filled with natural rain water and contains a small screened tub into which Robert placed 10 salamander eggs. The larvae, after they hatch and have used up all of their yolk reserves, feed on whatever zooplankton have sprung up in the ponds--a quick glance showed that copepods, ostracods, and insect larvae had already taken up residence. The idea is that the salamander larvae will escape from their tubs into the pool at large, which will give them lots of room to grow up.

In a very real sense, this field trip ended where it started. Things don't always work out this nicely, and my Type A personality is pleased at both the symmetry and the closure. Because these field trips are necessarily snapshots of what is happening at a particular moment in a particular place, it can sometimes be difficult to connect them to the real world. This week, though, I feel that my students got the whole story, or at least the entire outline of it. This visit to FONM and FONR may very well be my favorite field trip of the class, because I learned so much about things that are new to me. Thank you, Joe, for arranging such an amazing day for us!

Over the long holiday weekend a little over a week ago we drove up the coast from Morro Bay back to Santa Cruz and stopped at Piedras Blancas to visit the elephant seals. At this time of year the breeding season is over and most of the seals have returned to sea. The adult females gave birth in late December or early January, were mated soon after, fasted for a month while they nursed a growing pup, and then abandoned said pup on the beach to resume the aquatic phase of their life. Same for the adult males, minus the birth and nursing part, of course. Oh, and most of the males didn't get to breed, either. Suffice it to say that the adult elephant seals have more or less abandoned the beach for now.

Elephant seals (Mirounga angustirostris) at Piedras Blancas
2019-02-17
© Allison J. Gong

Although there were still a lot of seals on the beach, much of the real estate was unoccupied. Contrast this to the same beach in November 2015, as the seals were starting to arrive for that breeding season:

Elephant seals (Mirounga angustirostris) at Piedras Blancas
2015-11-27
© Allison J. Gong

Elephant seal pups have a tough life. They are born in the dead of winter, on exposed coasts. While they are very young, one of the pups' greatest mortality risks is being run over and trampled to death by the adult males that are fighting for seniority and the right to mate with a harem of females. The moms do their best to fend off rampaging males, but the alphas are so much larger that they just run over anybody in their way. At this point in their life an elephant seal pup's main priority is to eat. They nurse almost constantly on milk that is about 50% fat. Pups are born wrinkled, with a lot of loose skin, but they soon fill out and take on the stereotypical look of fat sausages.

After four weeks of intensive nursing, a pup's life changes drastically. Its mother abandons it on the beach and returns to the sea to begin feeding again and restoring its much-depleted body stores. Remember, she has been nursing a pup and fasting for about a month and a half! Her pup is thus forcibly weaned, because she just leaves and doesn't come back. Researchers refer to these abandoned pups as weaners.

Pair of elephant seal (Mirounga angustirostris) weaners at Piedras Blancas
2019-02-17
© Allison J. Gong

Most of the seals on the beach in late February are weaners. They will stay on the beach for another two months or so. They have to wait until they molt from their soft baby coat into a more adult coat that will better insulate them in the cold water. And after they molt they have to learn how to swim. They'll make short forays into the surf and paddle around for a bit, learning how to maneuver their bodies in the water, and then return to land to rest. In the meantime they're not feeding. This is why it is crucial for them to pack on as much weight during the four weeks that they get to nurse. Attaining that 'sausage' look is directly related to a weaner's probability of a success launch into the ocean.

Pile of elephant seal (Mirounga angusirostris) weaners at Piedras Blancas
2019-02-17
© Allison J. Gong

But not everybody is a weaner. There are also some subadults on the beach. They, of course, swim perfectly well and can head back out to sea whenever they want. The subadults will also need to molt, but that doesn't happen until the early summer.

Subadult male elephant seal (Mirounga angustirostris) at Piedras Blancas
2019-02-17
© Allison J. Gong

Don't they have the dopiest faces?

Subadult male elephant seal (Mirounga angustirostris) at Piedras Blancas
2019-02-17
© Allison J. Gong

With the breeding season over, things will be quiet at the seal rookeries at Piedras Blancas and Año Nuevo. Both sites will get frantic again in December, when the adults return to land and the next reproductive cycle begins.

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