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1

One of my agenda items for spring break this week was to return to Elkhorn Slough and finish the hike that I started with my students a couple of weeks ago. I got out there only to be forcibly reminded that the visitor center, where the hike originates, is closed on Mondays and Tuesdays. Since I'd driven out there, I figured I might as well poke around the area and see what else would catch my eye. I ended up at Kirby Park, a public access area where kayaks put into the water. The tide was out when I arrived, shortly before noon, and the flats were occupied by foraging birds.

Shorebirds and gulls foraging at Kirby Park. 29 March 2016 © Allison J. Gong
Shorebirds and gulls foraging at Kirby Park.
29 March 2016
© Allison J. Gong

I was able to identify birds that forage in the water (avocets, northern shovelers, cormorants, and grebes) and birds that forage in mud (willets, marbled godwits, yellowlegs, and whimbrels), and there were others that I couldn't see well enough to ID. I didn't even really try with the gulls. I do know they weren't either western or California gulls, but that's about it. Someday I may be able to tackle the gulls, but with their multiple juvenile plumages they're a notoriously tough group to figure out.

Many areas of Elkhorn Slough have been invaded by the Japanese mud snail Battilaria attramentaria. This snail was accidentally introduced into the area as tag-alongs on Asian oysters that were imported for mariculture. Battilaria aren't very big, reaching lengths of about 30 mm, but they can occur in astounding densities. A researcher at the slough has documented how this invasive snail came to be so prevalent, and how it has affected the native California snail Cerithidea californica. From the boardwalk trail at Kirby Park I could look down and see many Batillaria in the exposed mud flat.

The invasive Japanese mud snail, Battilaria attramentaria, on the mud flats at Kirby Park. 29 March 2016 © Allison J. Gong
The invasive Japanese mud snail, Battilaria attramentaria, on the mud flats at Kirby Park.
29 March 2016
© Allison J. Gong

This isn't a particularly dense group of Battilaria, either. Across the highway towards the ocean there are mud flats that, when the tide is out, appear to be carpeted with wood chips; all the "wood chips" are the shells of living or dead Battilaria.

One of the Slough inhabitants that I find very interesting is the plant Cuscuta pacifica, commonly referred to as marsh dodder. Dodder is a parasitic plant, and at Elkhorn Slough its main host is pickleweed (Salicornia pacifica). Pickleweed is a perennial succulent that dies back in the winter; it is now beginning to regrow into the mounds that will be the predominant plant in the salt marshes of the Slough.

The first time I saw dodder I thought that some clown had vomited a can of orange Silly String over the pickleweed. I still think that's what it looks like:

Salt marsh dodder (Cuscuta salina) on its host plant pickleweed (Salicornia virginica). 29 March 2016 © Allison J. Gong
Salt marsh dodder (Cuscuta pacifica) on its host plant pickleweed (Salicornia pacifica) at Kirby Park.
29 March 2016
© Allison J. Gong

One of the clues that something interesting is going on with dodder is the orange color. We are used to thinking of plants as being green, or at least green-ish, because they are photosynthetic. Dodder, on the other hand, is a parasite and lives off the tissues of its host; it therefore has no need for chlorophyll, the green molecule that captures light energy used to fix carbon into organic molecules. Looking more closely at the structure of dodder gives you an idea of how it makes a living:

Dodder and pickleweed at Kirby Park. 29 March 2016 © Allison J. Gong
Dodder (C. pacifica) and pickleweed (S. pacifica) at Kirby Park.
29 March 2016
© Allison J. Gong

Dodder consists primarily of orange tendrils that wrap around the host plant. The tendrils penetrate into the vascular tissue of the host and begin withdrawing phloem (the syrupy solution of sugars) from it. Once the dodder has established this internal connection with the host, its own roots die and the dodder becomes entirely dependent on the host. A single plant of dodder can send its tendrils around multiple host plants. From an evolutionary perspective it is impossible to believe that host plants such as pickleweed don't have defenses against dodder. They may be able to repel the tendrils by producing noxious chemicals, but this is a topic that hasn't been well studied. Somebody needs to fix that, as inquiring minds want to know.

Dodder (C. pacifica) on pickleweed (S. virginica) at Kirby Park. 29 March 2016 © Allison J. Gong
Dodder (C. pacifica) on pickleweed (S. pacifica) at Kirby Park.
29 March 2016
© Allison J. Gong

Because I was so surprised at how quickly my sand dollar larvae (Dendraster excentricus) were developing, I checked my notebook from the invertebrate embryology course I took while in grad school to see if what I'm observing now is normal for these animals. It turns out that yes, Dendraster does develop at a much quicker rate than its cousin the sea urchin. And now that I think of it, when I took that 5-week embryology course the sand dollars were the only echinoids that we followed all the way to competence; we spawned and observed urchins as well, but none of them were as far along as the sand dollars by the time the class ended and we "graduated" our larvae off the dock.

Yesterday my Dendraster larvae were five days old. They already had two well-developed pairs of arms and were working on the third pair.

Pluteus larva of the sand dollar Dendraster excentricus, age 5 days. 28 March 2016 © Allison J. Gong
Pluteus larva of the sand dollar Dendraster excentricus, age 5 days.
28 March 2016
© Allison J. Gong

These larvae are big, too--500 µm long. Of course, they started from eggs that were over twice the size of urchin eggs, but they've still grown a lot in only five days. The fourth pair of arms will be the preoral arms. At the rate these larvae are developing, I wouldn't be surprised if these arms show up in the next few days.

As beautiful as those long arms are, they may be a little too long. The larvae swim and gather food using a band of cilia that runs up and down all the arms; the entire body is ciliated, but the ciliated band is the primary locomotory system. I remember the instructor of my embryology course telling us that echinoid plutei will respond to lack of food by growing longer arms, which increases the length of the ciliated band and thus (presumably) the animal's ability to capture the food that is available. There are two pieces of circumstantial evidence that my larvae may be a little food-deprived: (1) the really long arms; and (2) the lack of visible food cells in the stomachs. In urchin plutei that are feeding well I can see food cells churning away in the stomachs. These Dendraster plutei have beautifully transparent bodies, but I don't see food in the guts. On they other hand, they are growing, so obviously they are eating. Just in case they are short of food, though, I'll increase their food ration for the next few days and see how the animals respond.

In the meantime, I continue to be fascinated by the intricacy of the larval skeleton and the complexity of the skeletal rods themselves. Next time I'll try to take photos of these.

My sand dollar larvae are developing very quickly! When I checked on them Thursday afternoon about 24 hours post-fertilization, I anticipated seeing them up in the water column because that's how long it takes urchins to hatch. Remember, sea urchins and sand dollars are in the same taxonomic class (Echinoidea) and share a larval form called the echinopluteus. I've watched urchin development often enough that I have a sort of intuitive feel for how it goes, and am subconsciously comparing these sand dollars to the urchins' time table. I need to stop doing that.

Anyway, on Thursday the sand dollars had indeed hatched. The big surprise was that when I examined them under the microscope I saw that they were much further along than urchin embryos would be at the same age. I expected to see the embryos swimming around as blastulae (hollow balls of ciliated cells); however, these sand dollar embryos had almost completed the process of gastrulation to form their archenteron, or first gut.

Gastrulating embryo of the sand dollar Dendraster excentricus, age 24 hrs. 24 March 2016 © Allison J. Gong
Gastrulating embryo of the sand dollar Dendraster excentricus, age 24 hrs.
24 March 2016
© Allison J. Gong

In echinoids the archenteron develops from an invagination into the blastula. Imagine a balloon. Now imagine poking your finger into the balloon--you've just made an invagination. If you continue the invagination across the entire balloon until your fingertip pops out on the other side, you've created a tube that penetrates through the balloon. This tube is the archenteron. Interesting tangent: You know that any one-way gut has two openings, right? One is the mouth and the other is the anus. The point in the blastula where gastrulation begins is called the blastopore. The fate of the blastopore is to be either the mouth or the anus of the archenteron. Echinoderms are deuterostomes ("second mouth"), a term that means the blastopore becomes the anus and the mouth is the second opening that forms when the invagination punches through to the other side of the blastula. Yes, sea urchins and sea stars and sand dollars all have an anus before they have a mouth. And guess what? So did you. The chordates, including us, are also deuterostomes.

These sand dollar embryos went from zygote almost to feeding larva in only 24 hours. In fact, some of them may have had mouths when I looked at them on Thursday. I had to start feeding them, so that food would be available as soon as they were able to eat.

Another 24 hours later, on Friday afternoon, I checked on the larvae again and they were bona fide plutei already. They had the cup-shaped body body of the pluteus larva and two pairs of arms, with complete guts. The stomachs in these larvae are huge, occupying almost the entire volume of the main body of the animal. Some of the larvae are also developing red pigment spots.

Early four-armed pluteus larva of Dendraster excentricus, age 2 days. 25 March 2016 © Allison J. Gong
Early four-armed pluteus larva of Dendraster excentricus, age 2 days.
25 March 2016
© Allison J. Gong

See how big and round that tummy is?

And how could I have forgotten that the plutei of Dendraster have fenestrated arm rods??? They are so beautiful! This is the same animal as in the photo above, but I focused in on the skeletal rods in the postoral arms. See the fenestrations in the rods? The larva is about 300 µm long.

Pluteus larva of D. excentricus, age 2 days. 25 March 2016 © Allison J. Gong
Pluteus larva of D. excentricus, age 2 days.
25 March 2016
© Allison J. Gong

For whatever reason, plutei of the local species of sea urchins don't have fenestrated arm rods. This difference in larval morphology between the two most common echinoid species in the area should make it easy to identify plutei collected in plankton tows. We're at the beginning of the spring bloom now, and I hope to keep an eye on how the plankton community develops through the spring and summer.

The next day I examine the larvae is Monday. I'll see if they're still on the fast track to metamorphosis.

This afternoon I met up with Joanna and Amy, who had come to the marine lab with some sand dollars (Dendraster excentricus) to try to spawn. Since sand dollars are in the same taxonomic group (the Echinoidea) as sea urchins, I'd try the same techniques on these animals I'd never spawned before. I did have to modify some things a bit, mostly to account for the difference in body shape between sand dollars and urchins. Urchins are globular, with quite a large internal body volume, while sand dollars are flat. There's much less space inside a sand dollar for gonads and guts.

Gravid echinoids such as urchins and sand dollars can be pretty easily induced to spawn by injecting their internal body cavity with a solution of KCl. We shot up all eight sand dollars and five of them spawned, two males and three females. One of the males didn't give enough sperm to be collected, so we didn't use his gametes. The other male, though, gave us lots of sperm. And they were good sperm, too.

Live sperm of the sand dollar Dendraster excentricus, 400X magnification. 23 March 2016 © Allison J. Gong
Live sperm of the sand dollar Dendraster excentricus, 400X magnification.
23 March 2016
© Allison J. Gong

If you've never had a chance to see swimming sperm under a microscope, today is your lucky day!

And the eggs. Wow, sand dollar eggs are freakin' cool! For one thing, they're big, ~130 µm in diameter, compared to the 80 µm eggs of the purple urchin Strongylocentrotus purpuratus. Plus, they have a really thick jelly coat that contains red pigment cells; urchin eggs don't have the pigment cells, either.

Eggs of the sand dollar Dendraster excentricus. 23 March 2016 © Allison J. Gong
Eggs of the sand dollar Dendraster excentricus
23 March 2016
© Allison J. Gong

The eggs themselves were a little lumpy, not as perfectly round as I'm used to seeing with the urchins, but they fertilized just fine. In all three of the crosses, the fertilization rate was 90-95%. Apparently the sperm have no problem digging through the jelly coat to get to the egg surface.

Zygote of D. excentricus. 23 March 2016 © Allison J. Gong
Zygote of Dendraster excentricus
23 March 2016
© Allison J. Gong

In this photo you can see the familiar fertilization envelope raised off the surface of the egg, as well as the red pigment cells in the jelly coat. This may very well be the most beautiful zygote I've ever seen. How many people can say things like that?

After an hour and 20 minutes sitting on my desk at room temperature the zygotes started to cleave:

2-cell embryos of Dendraster excentricus 23 March 2016 © Allison J. Gong
2-cell embryos of Dendraster excentricus
23 March 2016
© Allison J. Gong

The blastomeres are still a little wrinkled and lumpy, but I think they'll be okay. I've poured them into 1000-mL beakers and they're sitting in one of my seawater tables. Tomorrow afternoon I hope to see them swimming up in the water column. Fingers crossed!

So. I have a batch of larvae from a spontaneous spawning of the leather star, Dermasterias imbricata, that occurred four weeks ago tonight. Until now I've never had an opportunity to work with this species, even though we have quite a few of them at the marine lab. I had my own for several years, until they became casualties of the plague about a year into the current sea star wasting syndrome event. In any case, this is the first time I've been able to spend time with larvae of this species. At the very least I wanted to see how big they would get and how quickly they would develop, compared to the species I'm more familiar with, Patiria miniata (bat star) and Pisaster ochraceus (ochre star).

When the Dermasterias spawned, the first thing I noticed was that the eggs are huge. I measured them at 220 µm in diameter, which is big even compared to what I've seen in other stars. Hatch rates were pretty good, and four days later the larvae were already in the 400-430 µm range. Since I have no experience culturing this species, I thought I'd divvy up my larvae and put them into three feeding treatments to see which larval diet resulted in the best overall success. According to the literature, Dermasterias larvae can be raised on a mixture of the unicellular algae Dunaliella tertiolecta (green) and Isochrysis galbana (golden). My three feeding treatments are: Dun only, a Dun/Iso mix, and Iso only.

A week into the experiment there was a clear difference between the larvae eating only the green food, and those eating either a mixture of green and golden or only the golden. Larvae from all food treatments were about the same size, but the ones eating only Dunaliella had noticeably green guts.

Bipinnaria larva of Dermasterias imbricata. 29 February 2016 © Allison J. Gong
Bipinnaria larva of Dermasterias imbricata, fed on Dunaliella tertiolecta, age 7 days.
29 February 2016
© Allison J. Gong
Bipinnaria larva of Dermasterias imbricata, fed on a mixture of D. tertiolecta and I. galbana. 29 February 2016 © Allison J. Gong
Bipinnaria larva of Dermasterias imbricata, fed on a mixture of Dunaliella tertiolecta and Isochrysis galbana, age 7 days.
29 February 2016
© Allison J. Gong
Bipinnaria larva of Dermasterias imbricata, fed on I. galbana. 29 February 2016 © Allison J. Gong
Bipinnaria larva of Dermasterias imbricata, fed on Isochrysis galbana, age 7 days.
29 February 2016
© Allison J. Gong

Fast forward two weeks, and the larvae were 20 days old. By this time they had progressed from the bipinnaria stage to the brachiolaria stage. The interesting thing was the absence of green pigment in any of the guts, even those that were eating only green food. The D. tertiolecta larvae looked good, actually. They were a little smaller than the other larvae but were perfectly formed.

Brachiolaria larva of Dermasterias imbricata, fed D. tertiolecta, age 20 days. 14 March 2016 © Allison J. Gong
Brachiolaria larva of Dermasterias imbricata, fed D. tertiolecta, age 20 days.
14 March 2016
© Allison J. Gong
Brachiolaria larva of Dermasterias imbricata, fed D. tertiolecta and I. galbana, age 20 days. 14 March 2016 © Allison J. Gong
Brachiolaria larva of Dermasterias imbricata, fed D. tertiolecta and I. galbana, age 20 days.
14 March 2016
© Allison J. Gong
Brachiolaria larvae of Dermasterias imbricata, fed I. galbana, age 20 days. 14 March 2016 © Allison J. Gong
Brachiolaria larvae of Dermasterias imbricata, fed I. galbana, age 20 days.
14 March 2016
© Allison J. Gong

Obviously all of the larvae are assimilating enough of their food to grow and develop normally. I looked at them today but didn't have time to take pictures. Qualitatively there is no difference between the Dun larvae and the Dun/Iso larvae. In the Iso jars, however, there are many larvae at earlier stages; some are still at the "jellybean" stage. I don't know if this is because these larvae are developing more slowly, or because of some nonrandom distribution of earlier stages into those jars when I was setting up the feeding treatments.

Next week I'll measure the larvae again, and will have three data points to track growth trajectories.

2

For as long as sentient humans have walked across the surface of the planet, they have observed the world around them. Quite often these observations had direct life-or-death consequences, as most of survival had to do with finding food while not becoming someone else's dinner. Fast forward a few million years and we find ourselves mired in technology, often interacting with the outside world through some sort of digital interface. And yes, I totally get the irony of writing that statement in a blog. Be that as it may, I've found that people generally don't pay much attention to what's going on around them. My job as a biology professor is to teach some of the forgotten skills of the naturalist, including the practice of observation.

Today I took my Ecology students birdwatching. We looked at other things, of course, but birds were the primary focus of today's observations. We started the day near the mouth of Elkhorn Slough in Moss Landing, where we were immediately challenged to identify some shorebirds. Fortunately we had a guest lecture from a seabird biologist yesterday, and she gave us some important clues to help us with our field IDs.

Some shorebirds are fairly easy to identify, such as this long-billed curlew (Numenius americanus). It was foraging in a stand of pickleweed just off the road, which is the only reason I was able to take a decent photo of it.

Long-billed curlew (Numenius americanus) at Elkhorn Slough. 18 March 2016 © Allison J. Gong
Long-billed curlew (Numenius americanus) at Elkhorn Slough.
18 March 2016
© Allison J. Gong

We also saw marbled godwits (Limosa fedoa), willets (Tringa semipalmata), as well as the flocking "peeps," which we never got a really good look at but all agreed might have been sanderlings (Calidris alba).

One of the things we had been warned about was the difficulty of identifying gulls. There are some features that help when the birds are in adult breeding plumage, but gulls go through several juvenile plumages before attaining their adult colors and there's a lot of phenotypic overlap among species. Case in point:

Gulls (Larus spp.) on Moss Landing State Beach. 18 March 2016 © Allison J. Gong
Gulls (Larus spp.) on Moss Landing State Beach.
18 March 2016
© Allison J. Gong

Some of these adults are western gulls (Larus occidentalis) but some look different (smaller bodies, different beak coloration). They might be sub-adult westerns or another species entirely. And even the birds in juvenile plumage varied a lot; some were speckled or mottled while others were more uniformly colored. Several birds (not in this photo) had pale gray backs and pale tan flanks. According to my field guide, National Geographic's Field Guide to the Birds of North America, there are several species that have this plumage in their second or third winter. We kind of gave up on the gulls, but to be honest we didn't have a lot invested in identifying them.

The highlight of the beach part of the field trip, at least for me, was seeing snowy plovers (Charadrius nivosus). These tiny birds are perfectly colored to hide in the sand, and unless they move they are almost impossible to see. I found them because we unwittingly wandered too far up the beach towards the dunes and accidentally flushed them from their divots in the sand.

Snowy plovers (Charadrius nivosus) at Moss Landing State Beach. 18 March 2016 © Allison J. Gong
Snowy plovers (Charadrius nivosus) at Moss Landing State Beach.
18 March 2016
© Allison J. Gong

Can you spot all four plovers in this photo? Here's another quartet:

Snowy plovers (Charadrius nivosus) at Moss Landing State Beach. 18 March 2016 © Allison J. Gong
Snowy plovers (Charadrius nivosus) at Moss Landing State Beach.
18 March 2016
© Allison J. Gong

This morning I saw my first humpback whale of the season. A couple of whale watching boats were lingering around the mouth of the harbor, which should have clued us in that there was something going on. However, it took a kayaker to tell us that there were breaching humpbacks just off the jetty before we realized. And I call myself a naturalist? Sheesh.

This bird is, I think, a third-winter western gull (L. occidentalis).

Western gull (Larus occidentalis) at Elkhorn Slough in Moss Landing, CA. 18 March 2016 © Allison J. Gong
Western gull (Larus occidentalis) at Elkhorn Slough in Moss Landing, CA.
18 March 2016
© Allison J. Gong

This species is endemic to the California Current, which means that it is found nowhere else. The pink legs are characteristic of western gulls, and the black on the tip of the bill indicates a third-winter bird. Adults have a red spot towards the end of the bill but not on the very tip. If you look closely you can see that this bird has a tiny bit of red immediately proximal to the black smudge.


After lunch we convened at the Elkhorn Slough National Estuarine Research Reserve visitor center, across the highway and inland a bit from our morning site. The students got a 30-minute orientation to the history and geography of the Slough, then we went on a hike.

Orientation to the Elkhorn Slough National Estuarine Research Reserve. 18 March 2016 © Allison J. Gong
Orientation to the Elkhorn Slough National Estuarine Research Reserve.
18 March 2016
© Allison J. Gong

The first leg of the hike was a short walk to what is appropriately called the overlook. This is where I gave the students their only real assignment of the day. They had to spend 10 minutes in silent observation. They could write in their notebooks and look around with binoculars, but they were not allowed to talk at all. With some groups this is a nigh-impossible feat, but these students did a fantastic job. After the 10-minute observation period we discussed what they had seen and heard. One student said he heard 26 bird calls, but didn't know how many of them were the same bird making different calls. Others mentioned the sounds of human activity--traffic on the highway, planes flying overhead, the beep-beep-beep of a truck in reverse--as well as the buzz of insects and birds. I asked if anyone else had noticed the shadow of a turkey vulture that flew directly over us.

Silent observation period at Elkhorn Slough. 18 March 2016 © Allison J. Gong
Silent observation period at Elkhorn Slough.
18 March 2016
© Allison J. Gong

I think this is a very valuable exercise and would like to extend this period of silent observation to 15 or 20 minutes for future classes. In a lot of ways class always feels a little frantic, and to slow down and simply be a part of nature is a luxury of time that many of us don't have. Alas, we had other places to visit on the hike and needed to get moving again.

Turkey vulture (Cathartes aura) in flight over Elkhorn Slough. 18 March 2016 © Allison J. Gong
Turkey vulture (Cathartes aura) in flight over Elkhorn Slough.
18 March 2016
© Allison J. Gong

Much of Elkhorn Slough used to be a dairy, and the Slough is still surrounded by agricultural fields. There are two barns on the Reserve, named Big Barn and Little Barn. Little Barn is used for equipment storage and isn't open to the public, but you can walk into Big Barn. There are two barn owl boxes in Big Barn. We searched under them for owl pellets; we didn't find any intact pellets but did see some that had been dissected by previous human visitors.

Little Barn (foreground) and Big Barn (background) at Elkhorn Slough. 18 March 2016 © Allison J. Gong
Little Barn (foreground) and Big Barn (background) at Elkhorn Slough.
18 March 2016
© Allison J. Gong

I don't think I've ever seen this much green at Elkhorn Slough. All of the El Niño rains have brought forth a lot of wildflowers and grasses. We hiked past a large stand of non-native poison hemlock (Conium maculatum) on our way to Big Barn. That stuff is going to be difficult to eradicate, as it spreads quickly and outcompetes native species. And yes, this plant is highly toxic to mammals and was, in fact, used by the ancient Greeks for human executions (including that of Socrates).

When we returned to the visitor we asked the Reserve's naturalist, Jane, to take our picture. So this is class photo #1 of the semester. It's not complete, as three students were absent today. I hope to get a picture of the entire class another day.

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I wanted to take the students to the woodpeckers' acorn granary, but we didn't have time to hike that far. Spring break is coming up week after next, and I think I'll go back to the Slough to say "hello" to the family of acorn woodpeckers. I'm looking forward to having more time than I do at the moment to play outdoors. I want to do some drawing, too!

After pretty much neglecting us in February, El Niño has returned with a bang in March. Late yesterday and last night a weather station near me, more or less at sea level, recorded 4.67 inches of rain and wind speeds of 15 mph. Stations in the Santa Cruz mountains recorded close to 6 inches of rain yesterday, and there were patchy power outages throughout the county. This morning I woke to sunny, clear skies. Beautifully clear, with white puffy clouds. The forecast calls for another storm to head in this evening, giving me a window of opportunity to run up the coast and grab some mussels.

I have to say, El Niño's timing could be better. We have alternating weeks of spring and neap tides, and this winter the storms seem to be arriving during the spring tides. More than one tide series has been washed out because of storm surge and majorly big swell. I had figured that this would be the case today, so I didn't expect to get very far down in the intertidal. However the only thing I absolutely had to collect was mussels and I don't need a very low tide for those. It was very unlikely that I'd be unable to collect them, and at the very least I'd be able to take some photos.

Walking across the beach to the rocks, I noticed my first Velella of the season. As usual for these strangely wonderful animals they were gathered into windrows at the high tide level. Many of them were very small, less than 1 cm long, and the largest I saw was about the length of my thumb.

Velella velella stranded on the beach at Davenport Landing. 6 March 2016 © Allison J. Gong
Velella velella stranded on the beach at Davenport Landing.
6 March 2016
© Allison J. Gong

While it is not at all unusual to find Velella washed up on the beach, I did find some in a place that I didn't expect. More on that in a bit.

Conditions in and on the water were pretty rough. There were no surfable waves, therefore no surfers. They'd have been beat up by the waves crashing in all directions.

Rough water at Davenport Landing Beach. 6 March 2016 © Allison J. Gong
Rough water at Davenport Landing Beach.
6 March 2016
© Allison J. Gong

On a calmer day, the water at this beach can be glassy smooth with very gently breaking waves. Not so today:

Easily accessible beaches such as this one are typically crowded for these afternoon low tides. Most of the people there are just hanging out with their friends, family, and dogs. Every once in a while, however, I run into people who might not be entirely on the up and up. Much of the coast in California is designated as a marine protected area (MPA), and while allowed activities vary from MPA to MPA, in general I don't have permission to collect at any of them with my current state-issued scientific collecting permit. This means that collecting, both scientific and recreational, is concentrated into the few places where it is allowed.

Today I arrived at the parking area at the same time as a family of three adults and about five kids. The men were wearing wellies and carrying 5-gallon buckets. It was clear that they were going to be collecting something. I can't really say that I looked any different, in my hip boots and with my own bucket, so I just smiled a greeting to them and headed out on my way. Given that there was so little exposed rock, we were bound to keep running onto each other. At one such meeting I asked what they were doing, and they said they were collecting mussels to eat. I said I was, too, to use as food for animals at the marine lab. They asked what the limit was. I told them that I didn't know what the limit was for taking with a marine fishing license (assuming that they had one), but the limit for my collecting permit is 35. We nodded and went our separate ways.

Now, I'm not a game warden and it's not my job to enforce the state's rules about collecting, or even to see if other citizens have the appropriate permits or licenses. I generally feel that the better part of valor is to mind my own business. These guys today were friendly enough and completely non-threatening, but my gut instinct tells me that they didn't have a fishing license. Is that any of my business? I don't think so; yet as a citizen of this state I have a vested interest in protecting our wildlife from unlawful take. I know there aren't enough wardens to patrol all beaches all the time, and now that I think about it I don't know that I've ever been stopped by a warden on an afternoon low tide. The enforcement strategy seems to be to let citizens patrol each other, in the sense that skullduggery is less likely on a crowded beach in the broad daylight of afternoon than at the crack of dawn on a morning low tide.

Anyway, on to the matter at hand. I've noticed that recently my eye has been drawn to patterns that occur among whatever objects happen to be around. Scrambling down a little cliff and continuing up the coast I noticed these smears of algae growing on the vertical sandstone face. It's not that I hadn't seen them before, but because of the recent rain there was water running down the cliff face, which added a sheen to the green algae that they don't have when they're dry.

Streaks of green algae on sandstone cliff face at Davenport Landing. 6 March 2016 © Allison J. Gong
Streaks of green algae on sandstone cliff face at Davenport Landing.
6 March 2016
© Allison J. Gong

At this site there are some little caves that you can get to at low tide. The tide wasn't low enough to reach the caves that go back any appreciable distance, but I did get to a small one. It was more of deep fissure than a cave, really, large enough to duck into but only a couple of meters deep. The really cool thing about it was the waterfall cascading over the opening. Again, without the runoff from yesterday's rain this little waterfall wouldn't even exist.

Also, there is quite a bit of stuff living inside the cavelet. Not much in the way of algae, of course, with the exception of both encrusting and upright corallines, but in terms of animals there was more or less the same fauna that I'd expect in the high-mid intertidal.

Cavelet at Davenport Landing Beach. 6 March 2016 © Allison J. Gong
Cavelet at Davenport Landing Beach.
6 March 2016
© Allison J. Gong

The biggest surprise in this little cave was Velella! A bunch of them had apparently gotten washed up into the fissure by the last high tide. I found them stuck amongst barnacles and algae.

Velella velella stuck to coralline alga inside cave at Davenport Landing. 6 March 2016 © Allison J. Gong
Velella velella stuck to coralline algae inside cave at Davenport Landing.
6 March 2016
© Allison J. Gong

This one was maybe half the length of my thumb. On the opposite side of the cave a crab was taking advantage of this unusual bounty.

Small shore crab (Pachygrapsus crassipes) dining on a mangled Velella velella in a cave at Davenport Landing Beach. 6 March 2016 © Allison J. Gong
Small shore crab (Pachygrapsus crassipes) snacking on a mangled Velella velella in a cave at Davenport Landing Beach.
6 March 2016
© Allison J. Gong

I can't imagine there's much nutrition in a Velella for a crab, but the animal is always right even (especially?) when it doesn't make sense to us. The crab knows what it's doing.

All told, it was a short but very satisfying little jaunt to the intertidal. The clouds had spent the afternoon talking about whether or not to build to anything, and by the time I left they'd come to consensus. The wind is picking up now, the rain should start soon, and the National Weather Service says we may be in for thunderstorms tonight. I'm tucked up at home, warm and dry. Have a good evening, everybody!

Davenport Beach

This year I'm teaching Ecology for the second time. It is a field-intensive course: we have all day on Fridays to meet outside the classroom and do something outdoors. Most people understand that hands-on experiences are the best way to learn, whether the subject matter is field-based or computer-based (such as working with software for statistical analyses), and part of my job this semester is to provide as many diverse experiential activities as I can for my students. As I am a marine biologist by training and inclination the course is biased towards marine ecology, but I'm doing my best to include terrestrial activities as well.

Today we visited the Younger Lagoon Reserve on the Long Marine Lab campus, to participate in the ongoing habitat restoration project. We were met by Beth Howard, the reserve manager, and Tim Brown, the reserve steward, who gave us a brief history of the reserve and the conservation work going on there.

Beth (aqua jacket) and Tim (yellow jacket) give us the rundown on restoration at the Younger Lagoon Reserve. 4 March 2016 © Allison J. Gong
Beth (aqua jacket) and Tim (yellow jacket) give us the rundown on restoration at the Younger Lagoon Reserve.
4 March 2016
© Allison J. Gong

We are standing in a plot that had very recently (as in within the last week) been planted with young grasses. The reserve staff, volunteers, and student interns collect seeds from local populations of native plants, germinate and grow them up in the greenhouse, and then plant them the following spring. The idea is that in a few years the larger scrub plants, such as coyote bush and sticky monkey flower, will outcompete the non-native weeds and the plant community will more or less take care of itself. The annual flowering plants should re-seed and repopulate the area at the end of the season.

The master design in this area of the Younger Lagoon Reserve. 4 March 2016 © Allison J. Gong
The master design in this area of the Younger Lagoon Reserve.
4 March 2016
© Allison J. Gong

Tim, as the reserve steward, designed this bit of the reserve. The areas within the polygons are to be planted with flowering annuals, while the spaces between polygons are to be filled with perennial grasses. To make seed gathering easier, we were told to plant in patches, resulting in medium-sized patches of several plants of one species grouped together.

In addition to helping plant upwards of 1500 plants today, we got to see how last year's plants are doing! I'm proud to report that they have filled in beautifully and grown a lot:

On the right: Plants that my students and I planted last year. On the left: Plants that were set out about a week ago. Younger Lagoon Reserve. 4 March 2016 © Allison J. Gong
On the right: Plants that my students and I planted last year. On the left: Plants that were set out about a week ago. Younger Lagoon Reserve.
4 March 2016
© Allison J. Gong

Not all the vegetation in the right side of the photo was the stuff that we planted last year. Some of it was weeds. The reserve workers are about to shift from planting mode to weeding mode, to remove as many weeds as possible before they have a chance to flower and set seed.

When it was time to start the actual planting, we were shown how to make holes and insert the baby plants.

Demonstration of the "dibble dance." Younger Lagoon Reserve © Allison J. Gong
Demonstration of the "dibbler dance." Younger Lagoon Reserve
© Allison J. Gong

The dibbler is a nifty tool that makes holes in the ground. You clear off the layer of mulch, shove the dibbler into the soil, and wiggle it around, making a perfectly round hole. The plants are grown in cone-tainers, that not-so-coincidentally are the exact same size and shape as the holes made by the dibbler. I asked Beth, and she confirmed that the dibbler and cone-tainers are made by the same company. Once the dibbler has made the hole you remove a plant from a cone-tainer, stick it in the hole, tamp down the soil around it, and replace the mulch.

We were instructed to place the holes 18" apart, and not in a strict grid pattern. The goal is to restore a natural setting, not create a formal garden. After the instructions we all got to play in the dirt.

Student working at YLR Students at YLR Student at YLR Students at YLR

In addition to planting flowering annuals in a couple of the polygons, we also did this:

Native grasses my students and I planted at Younger Lagoon Reserve. 4 March 2016 © Allison J. Gong
Some of the native grasses my students and I planted at Younger Lagoon Reserve.
4 March 2016
© Allison J. Gong

After our work in the field we went across the marine lab to Younger Lagoon. It rained on us for a while, and we sheltered under the lean-to and looked out over the lagoon. It's beautiful even in the rain.

Younger Lagoon 4 March 2016 © Allison J. Gong
Younger Lagoon
4 March 2016
© Allison J. Gong
Male red-winged blackbird (Agelaius phoeniceus) at Younger Lagoon. 4 March 2016 © Allison J. Gong
Male red-winged blackbird (Agelaius phoeniceus) at Younger Lagoon.
4 March 2016
© Allison J. Gong

This red-winged blackbird was loudly staking his claim to a bit of territory. He never showed off his red epaulettes, though. Another bird was replying from the top of a cypress tree a short distance away. The back-and-forth went on for about five minutes, before one of the birds flew off.

For the first time I got to hike the trail that parallels the east side of Younger Lagoon. We didn't go down onto the beach, but I was able to see a perspective of the large rock at the mouth of the lagoon that I'd never looked on before.

Large rock at the mouth of Younger Lagoon. 4 March 2016 © Allison J. Gong
Large rock at the mouth of Younger Lagoon.
4 March 2016
© Allison J. Gong

Does anybody else see the profile of Abraham Lincoln in this rock?

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