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Published on 1 Comment on Beauty at low tide

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

Published on Leave a comment on Nature journaling

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

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

Anyway, here are my pages.

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

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

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

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

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

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Published on 1 Comment on A snail’s pace

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

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

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

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

Black turban snails (Tegula funebralis)
2021-05-15
© Allison J. Gong

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

Published on Leave a comment on Down to business

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

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

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

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

Cliff swallow (Petrochelidon pyrrhonota) starting to build its nest
2021-05-05
© Allison J. Gong

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

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

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

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

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

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

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

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

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

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

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

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

Published on Leave a comment on From the tidepool to the stars

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

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

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

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

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

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

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

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

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

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

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

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

Published on Leave a comment on All dressed up with nowhere to go

For animals that do essentially nothing when you see them where they live, chitons have a lot of charm. They are the kind of animal that, once you develop the search image for them, you start seeing everywhere. It helps that they are easily recognized as being chitons because of their eight dorsal shell plates—nothing else looks like them. Depending on species, those shell plates can be smooth or sculpted, and pigmented or not. Patterns of sculpting and pigmentation (or lack thereof) are diagnostic features used to distinguish different species. Some species are reliably consistent in appearance and look the same wherever you happen to see them. Other species show a lot of phenotypic variation, often even at a single site.

One of my favorite chitons is Mopalia muscosa, the mossy chiton. It's one of the easiest of our chitons to identify, because its girdle (the layer of tough tissue in which the shell plates are embedded) is densely covered by long, curved spines. They're called spines, but they're quite soft and flexible. Your basic Mopalia muscosa looks like this:

Mossy chiton with bare shell plates, in the rocky intertidal
Mossy chiton (Mopalia muscosa) at Pigeon Point
2016-04-24
© Allison J. Gong

Mopalia muscosa is one of the species whose appearance is quite variable. Many of them wear algae, usually reds but occasionally greens or browns, on their shell plates. Not all species of chiton do this. I've often wondered why some chiton species wear algae and others do not. This individual is probably fairly old, judging by the worn condition of the shell plates. The plates show signs of erosion, but are not decorated. There are some small pieces of coralline algae amongst the spines of the girdle, though, which I always associate with age. Smaller, and presumably younger, M. muscosa tend not to have algae on the girdle even if they are wearing some on the shell plates.

The degree of shell decoration in M. muscosa varies from none, as above, to heavy encrustation. This individual below has been colonized by only a small bit of coralline algae and perhaps some brown diatom-ish film on the edges of the shell plates:

Mossy chiton (Mopalia muscosa) at Pistachio Beach
2021-02-09
© Allison J. Gong

This next one has only a small bit of coralline alga, but sports a jaunty sprig of something quite a bit larger.

Mossy chiton (Mopalia muscosa) at Asilomar
2019-07-04
© Allison J. Gong

This season's fashionable chiton will go all out with the coralline algae, wearing both encrusting and upright branching forms. Look at this:

Mossy chiton (Mopalia muscosa) at Pigeon Point
2017-06-28
© Allison J. Gong

and this:

Mossy chiton (Mopalia muscosa) at Pigeon Point
2018-01-01
© Allison J. Gong

Sometimes the chitons wear the larger leafy red algae, in addition to or in place of the coralline algae. I always think that these individuals must be very old, by chiton standards.

Mossy chiton (Mopalia muscosa) at Pigeon Point
2020-11-14
© Allison J. Gong

And sometimes the chitons are so covered with algae that they blend in perfectly with the surrounding environment.

Mossy chiton (Mopalia muscosa) at Pistachio Beach
2021-04-06
© Allison J. Gong

These chitons can get very heavily fouled by algae. Is there any benefit to the chiton, to carry around a load of red algae? And if wearing algae is for some reason advantageous, is there a way for a chiton to attract algae to settle on their shell plates? Well, let's think about that. Chitons' main predators would be sea stars, crabs, and birds. Sea stars do not locate prey visually, so camouflage would not be very helpful in avoiding them. Birds such as oystercatchers and surfbirds certainly do pry up chitons and limpets, and blending in with the background just might help a chiton go unnoticed by an avian hunter.

Regarding the matter of how the algae end up living on chitons' bodies, I want to start with the question of how prevalent algal fouling is on Mopalia muscosa, and the extent of fouling on the chitons that are wearing algae. A little research study might be a fun way to spend my time in the intertidal. Pigeon Point is a lovely site on a foggy summer morning, and many of the most heavily decorated M. muscosa in my photo library are from there. Yes, I can foresee several visits up the coast over the next few months. Laissez les bons temps rouler!

Published on Leave a comment on Shooting star

This morning I went to Pigeon Point to poke around and do some collecting. It's a favorite site of mine, as it's exposed and dynamic, with the diversity you'd expect. Of the sea stars, the most common by far are the six-armed stars in the genus Leptasterias. They are small (less than 8 cm in diameter, often smaller than 1 cm), somewhat drably colored, and sometimes on the underside of rocks, all of which means that they are not always conspicuous. But once you get the right search image, you see them everywhere.

Six arms, see?

6-armed stars (Leptasterias sp.) at Pigeon Point
2021-04-03
© Allison J. Gong

Sea stars are well known for their ability to regenerate lost arms. It is not uncommon to see a star that looks healthy in every way except that one of its arms is shorter than the others. This must happen in Leptasterias, too. Searching through my library of pictures of Leptasterias, I did find a couple of examples of regeneration.

  • Regenerating two arms
  • Regenerating one arm
6-armed stars (Leptasterias sp.) regenerating lost arms, at Pistachio Beach
2019-06-19
© Allison J. Gong

When these stars finish regrowing those arms, they will have the typical number of arms for the genus, which is six.

Today I saw something that I'd never seen before. It was a Leptasterias that was regenerating arms. Only this was weird. It had three full-size arms and was growing four!

Sea star with 3 arms and regenerating 4 arms
Leptasterias star regenerating lost arms at Pigeon Point
2021-04-03
© Allison J. Gong

When (if) this star survives, it will eventually have seven arms. And that's strange. I asked my friend Chris Mah, who is the sea star systematist at the Smithsonian, if it was common for Leptasterias to do this. He said he'd never seen it, either. So it is indeed a rare phenomenon.

Now, there are stars in the genus Linckia that actually reproduce by deliberately leaving behind an arm, which then goes on to regenerate the rest of the body. While they do so they look like comets:

"comet" star. One arm is regenerating the remaining arms and central disc.
Linckia multiflora comet in the Maldives
Ahmed Abdul Rahman and Frédéric Ducarme for MDC Seamarc Maldives (CC BY-SA 4.0)

My regenerating Leptasterias isn't quite a comet, but it is doing something equally strange and wonderful. I really wished I could bring it to the lab and keep an eye on it over the next several months. However, Leptasterias are on the no-take list, I think because their populations are so patchy. It is extremely unlikely that I will ever see that same individual again, so we will never know what happens to it. Unless, of course, I happen to come across a 7-armed Leptasterias at Pigeon Point sometime in the future. If you see it, take a photo and let me know!

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Published on 3 Comments on The algae get sexy, again

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

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

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

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

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

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

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

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

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

Published on Leave a comment on Water fowl, in and out of the water

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

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

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

Entry in my nature journal

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

Let's start with the obvious:

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

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

Now take a look at these geese:

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

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

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

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

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

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

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

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

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

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

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

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

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

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

Published on Leave a comment on Weekend brunch

A utility pole across the street and one house down has, for years, been an object of interest for a variety of birds. The hairy and downy woodpeckers drum on it in the spring, and various songbirds hang out and rest on the top. About a month ago now I saw a raptor up there, eating something. It was a female merlin (Falco columbarius). According to Cornell's All About Birds, merlins are in our area during the nonbreeding season, but I've never been certain about having seen one.

On the morning of Saturday 13 March I went outside to look around, and saw a bird on the pole. It appeared to be either eating or cleaning its beak. I ran inside to grab the camera, which fortunately had my longest lens and the 1.4x teleconverter attached, and snapped off a bunch of shots. The sun was rising, but I was able to get some decent photos of the bird even though from the best vantage point it was backlit.

Clearly, he's eating something:

Male merlin (Falco columbarius)
2021-03-13
© Allison J. Gong

But what is it eating? Rodent bits?

Male merlin (Falco columbarius)
2021-03-13
© Allison J. Gong

No, look at that foot. It's a bird!

Male merlin (Falco columbarius)
2021-03-13
© Allison J. Gong

Yep. Definitely a bird.

Male merlin (Falco columbarius)
2021-03-13
© Allison J. Gong

And here he is, taking a break between courses:

Male merlin (Falco columbarius)
2021-03-13
© Allison J. Gong

Merlins are members of the falcon family. Smaller birds make up the majority of a merlin's prey, but they also eat large insects such as grasshoppers. As with peregrine falcons, merlin populations were severely reduced in the years when DDT was widely used to keep insect populations down, but they have since recovered. Truly, the recovery of birds of prey after DDT was banned is one of the great successes of conservation biology.

There were feathers in the street below the pole. I assume they are from the merlin's prey, as when I looked at the top of the pole through binoculars I could see the same sort of feathers up there. I compared the feathers with photos on a few ID sites, but it's no easy identifying feathers without any additional context. Someone suggested that they might be from a male house finch. We have lots of those around all the time, so that's probably the best guess possible.

Feathers from prey of a merlin (Falco columbarius)
2021-03-13
© Allison J. Gong

So there you have it: Saturday brunch with songbird on the menu!

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