Tag: natural history

The hunt begins

Posted on by Allison J. Gong

RAIN + SUN = WILDFLOWERS

That’s one of the truisms of life in a Mediterranean climate such as ours. The official water year as measured by NOAA runs from 1 October through 30 September, and along the central/northern California coast most of the rain falls from December through March. The rest of the year, April through the summer and most of the fall, is the long dry season.

Plants that have evolved to live in Mediterranean climates respond quickly to water when it is available. For many annual plants, this means rapid growth in the spring when the soil begins to warm up and the days are getting longer, followed by a burst of flowering as the plants complete their life cycles. Once the rain stops falling there is no water except what is stored in the ground, out of reach for most shallow-rooted plants. The annuals take advantage of the short window between the end of the heaviest rains and the onset of yearly drought to bloom and have sex (i.e., set seed). From 2011-2015 there was moderate to severe drought through most of the state and spring wildflower blooms were anemic and less-than-spectacular. In April 2016, after the El Niño rains of the previous season, some friends and I went down to southern California to check out the bloom. We had made a day trip of it, and it was a very long day that didn’t allow for much meandering or poking around. This year we had read from several sources that the heavy winter/early spring rains followed by sunshine would result in a very strong superbloom and managed to squeeze in a 3-day trip, which allowed us to visit more places and change our plans at the last minute if we heard about something interesting to see.

Day 1 (Thursday 23 March 2017): Shell Creek Road 

Shell Creek road is the little road that runs north-south from the hamlet of Shandon to the northwest corner of the Carrizo Plain. The roadbed runs along a little creek that meanders through rolling hills dotted with oak trees. It is really pretty when covered with grasses and wildflowers in the spring, although it will be hot, dusty, and brown for half the year. This is where we caught our first glimpses of the superbloom in action.

Wildflower bloom along Shell Creek Road in San Luis Obispo County
23 March 2017
© Allison J. Gong
Wildflower bloom along Shell Creek Road in San Luis Obispo County
23 March 2017
© Allison J. Gong

The dominant color of the landscape is yellow. A quick thumb-through of any western wildflowers field guide will confirm this. We do have a plethora of yellow flowers in California. In fact, one of the hypothesized reasons California is referred to as “the golden state” is the flood of yellow that carpets hills and valleys in the springtime. The other hypothesis I’ve heard is that “golden” refers to the color of the hills during the long dry season. Both of these seem feasible to me.

So who’s responsible for all this yellow?

The main culprit is the aptly named goldfields (Lasthenia californica). They are very common members of the daisy family, the Asteraceae, and are found in most regions of the state except at higher elevations in the Sierra Nevada.

Goldfields (Lasthenia californica) along Shell Creek Road in San Luis Obispo County
23 March 2017
© Allison J. Gong

Another goldfield look-alike is a flower with the strange common name of Bigelow’s tickseed. Its real name is Leptosyne bigelovii. It’s a California endemic, found only in the southern half of the state. I looked at a lot of photos, mine and others’, trying to learn how to distinguish between the tickseed and goldfields, and hope I have it right.

This is Bigelow’s tickseed:

Bigelow’s tickseed (Leptosyne bigelovii) along Shell Creek Road in San Luis Obispo County
23 March 2017
© Allison J. Gong

See the differences in flower morphology? I’ve got samples of each species (I hope!) drying in the plant press, and should be able either to confirm or refute my identifications once I can take a look at them. It’s always a good idea to calibrate my intuition whenever I can.

A third yellow flower, which occurs throughout the coastal mountains but we saw only at Shell Creek Road, is the delightfully named coastal tidy tips (Layia platyglossa). This is the kind of common name that makes me smile. You’ll see why.

Coastal tidy tips (Layia platyglossa) along Shell Creek Road in San Luis Obispo County
23 March 2017
© Allison J. Gong

Perhaps the tidy tips form large dense patches more readily at other locations, but this year we saw them mostly interspersed among the goldfields. They are conspicuous enough that I think I would have noticed them if I’d seen them last year. From a macro perspective the white petal tips lend a more creamy yellow color to the landscape, compared to the unrelenting blinding yellow of the goldfields. I had never seen them before, and there’s something about those white tips that just tickles my fancy. How could I not be enchanted?

Goldfields (Lasthenia californica) and coastal tidy tips (Layia platyglossa) along Shell Creek Road in San Luis Obispo County
23 March 2017
© Allison J. Gong

As lovely as it was, Shell Creek Road was only the first location we wanted to visit that day. Our ultimate destination was the Carrizo Plain National Monument, in southeastern San Luis Obispo County. More about that shortly.

Complexity in small packages

Posted on by Allison J. Gong

Last week I went up to Davenport to do some collecting in the intertidal. The tide was low enough to allow access to a particular area with two pools where I have had luck in the past finding hydroids and other cool stuff. These pools are great because they are shallow and surrounded by flat-ish rocks, so I can lie down on my stomach and really get close to where the action is. At this time of year the algae and surfgrasses are starting to regrow; the surface of the pools was covered by leaves of Phyllospadix torreyi, the narrow-leafed surfgrass.

Parting the curtain of Phyllospadix leaves to gaze into the first pool I was pleasantly surprised to find this. What does it look like to you?

Aglaophenia latirostris at Davenport Landing
8 March 2017
© Allison J. Gong

There are actually two very different organisms acting as main subjects in this photo. The pink stuff is a coralline alga, a type of red alga that secretes CaCO3 in its cell walls. Coralline algae come in two different forms: one is a crust that grows over surfaces and the other, like this, grows upright and branching. Because they sequester CaCO3, corallines are likely to be affected by the projected increase of the ocean’s acidity due to the continued burning of fossil fuels. Ocean acidification is one of the sexy issues in science these days, and although it is very interesting and pertinent to today’s world it is not the topic for this post. Suffice it to say that changes in ocean chemistry are making it more difficult for any organisms to precipitate CaCO3 out of seawater to build things like shells or calcified cell walls.

It’s the tannish featherlike stuff in the photo that I was particularly interested in. At first glance the tan thing looks like a clump of a very fine, fernlike plant. It is, however, an animal. To be more specific, it is a type of colonial cnidarian called a hydroid. I love hydroids for their hidden beauty, not always visible to the naked eye, and the fact that at first glance they so closely resemble plants. In fact, many hydroid colonies grow in ways very similar to those of plants, which has often made me think that in some cases the differences between plants and animals aren’t as great as you might assume. But that’s a matter for a separate essay.

I collected this piece of hydroid and brought it back to the lab. The next day I took some photos. To give you an idea of how big the colony is, the finger bowl is about 12 cm in diameter and the longest of these fronds is about 3 cm long.

Colony of the hydroid Aglaophenia latirostris
9 March 2017
© Allison J. Gong

And here’s a closer view through the dissecting scope.

The colonial hydroid Aglaophenia latirorostris
9 March 2017
© Allison J. Gong

Each of the fronds has a structure that we describe as pinnate, or featherlike–consisting of a central rachis with smaller branches on each side. This level of complexity can be seen with the naked eye. Zooming in under the scope brings into view more of the intricacy of this body plan:

Close-up view of a single frond of Aglaophenia latirostris, showing feeding polyps and two gonangia
9 March 2017
© Allison J. Gong

At this level of magnification you can see the anatomical details that cause us to describe this animal’s structure as modular. In this context the term ‘modular’ refers to a body that is constructed of potentially independent units. A colony like this is built of several different types of modules called zooids, some of which are familiarly referred to as polyps. Each zooid has a specific job and is specialized for that job; for example, gastrozooids are the feeders, while gonozooids take care of the sexual reproduction of the colony. In this colony of Aglaophenia each of these side branches consists of several stacked gastrozooids, which you can see as the very small polyps bearing typical cnidarian feeding tentacles. Aglaophenia is a thecate hydroid; this means that each gastrozooid sits inside a tiny cup, called a theca, into which it can withdraw for protection. Those larger structures with pinkish blobs inside are called gonangia. A gonangium is a modified gonozooid, found in only thecate hydroid colonies, that contains either medusa buds or other reproductive structures called gonophores.

Pretty complicated, isn’t it? Who would expect such a small animal to have this much anatomical complexity?

In the second pool I found an entirely different type of hydroid. At first glance this one looks more animal-like than Aglaophenia does, although it is still a strange kind of animal. This is Sarsia, one of the athecate hydroids whose gastrozooids do not have a protective theca. It might be easier to think of these and other athecate hydroids (such as Ectopleura, which I wrote about here and here) as naked, with the polyps not having anywhere to hide.

Colony of the athecate hydroid Sarsia sp.
9 March 2017
© Allison J. Gong

Each of these polyps is about 1 cm tall. The mouth is located on the very end of the stalk. The tentacles, not quite conforming to the general rule of cnidarian polyp morphology, do not form a ring around the mouth. Instead, they are scattered over the end of the stalk.

Here’s a closer view:

Colony of the athecate hydroid Sarsia sp.
9 March 2017
© Allison J. Gong

In the hydroid version of Sarsia, the reproductive gonozooids are reduced to small buds that contain medusae. You can see a few round pink blobs in the lower right of the colony above; those are the medusa buds.  The medusae are fairly common in the local plankton, indicating that the hydroid stage is likewise abundant. Here’s a picture of a Sarsia medusa that I found in a plankton tow in May 2015.

Medusa of the genus Sarsia
1 May 2015
© Allison J. Gong

The medusa of Sarsia is about 1 mm in diameter and has four tentacles, which usually get retracted when the animal is dragged into a plankton net. Sometimes, if the medusa isn’t too beat up, it will relax and start swimming. I recorded some swimming behavior in a little medusa that I put into a small drop of water on a depression slide. It refused to let its tentacles down but you might be able to distinguish four tentacle bulbs.

There’s a lot more that I could say about hydroids and other cnidarians. They really are among the most intriguing animals I’ve had the pleasure to observe, both in the field and in the lab. I’ve always been fascinated by their biphasic life cycle, with its implications for the animals’ evolutionary past and ecological present. Perhaps I’ll write about that some time, too.

Just a human, being

Posted on by Allison J. Gong

Recently I’ve been thinking a lot about our species’ relationship to the natural world. These musings have been brought on not only by my own impairment and inability to spend as much time in the field as I would like, but also by the current political climate in the U.S. Recent Executive Branch appointments and policy announcements make me fear that we, as a country, are going to be even more removed from the natural world than we currently are. This will have dire long-term consequences for all of us. Much has been made lately of federal cuts to spending on science and environmental protection. I am not qualified to address the economic aspects of cuts, but can speak to what I feel will be their effect on quality of life.

For several generations now, humans have become increasingly separated from the natural world around them. We live in cities surrounded by concrete and steel, most of us don’t grow or kill our own food, and we tend to view the natural world as “other,” differing from us in some fundamental way. Even among people who spend much of their leisure time outdoors, many at least occasionally view nature as something to be conquered–by climbing the highest peak, hiking the longest trail, visiting the deepest part of the ocean, or surfing the biggest wave. There isn’t necessarily anything wrong with testing your skills and challenging yourself to perform at the highest level possible. I do that all the time, by trying to learn the names and biology of the organisms I encounter in the wild. But if that’s what you’re doing every time you venture outdoors then you are missing out on something.

Sometimes you need to just be.

One of my graduate advisors, Todd Newberry, used to tell students when we went into the field to “get your face down where your feet are.” It was a simple phrase to remind students that none of the interesting stuff going on in the intertidal occurs at human eye level. And even things that you can see while standing up are very different when you observe them from the level at which they experience the world. For example, can you identify this very common and conspicuous animal from the intertidal at Natural Bridges?

7 March 2017
© Allison J. Gong

The observation skills that Todd taught us were the kind that reward patience and a certain ability to lose oneself in time. “Glance-and-go” was something that he taught us to despise as both lazy and weak, a mindset to be tolerated for a short time in rookies but completely unacceptable for anyone aspiring to the Varsity team. The true rewards of observation in the field come when you spend real time with the organisms, learning enough about them to imagine what their lives are like, and appreciating them for what they are instead of disregarding them for not being more like us.

In my experience there is something transcendent about simply being in nature. And I don’t mean temporarily occupying a bit of space that happens to be out-of-doors. I mean the act of immersing yourself, mentally as well as physically, in the natural world. I mean, instead of using your time outdoors to get from point A to point B or achieving some tangible goal such as bagging your limit or adding to your life list of species seen, stopping for a while and just being. Slowing down and stepping back from the frenzy of modern human life, even for a few minutes, allows you to notice things that ordinarily don’t catch your attention. Even seeing this happen second-hand is a lot of fun. One of the best things about taking students out in the field is hearing them exclaim, “I never noticed that before!”

I have to admit, though, that it’s not always easy to do this. Not everyone gets–or even wants–to make the Varsity team. Many people don’t have time in their busy lives to spend hours in the field every so often; certainly most don’t have the luxury of a job that requires spending time outdoors like I do. And of course there are those who just aren’t interested. That’s fine, too. After all, I’m not at all interested in the stock market, soccer, or stamp-collecting.

Now, back to that picture above. I bet that from this view, as you would see them from eye-level, you’d be able to made a good guess.

Organisms of the mid-intertidal at Natural Bridges
7 March 2017
© Allison J. Gong

These are the famous owl limpets, Lottia gigantea. They are the largest limpets on our coast, and are notable not only for their size (up to 10 cm long) but also for some rather extraordinary behavior. These large individuals, which occupy suspiciously blank areas of the mid-intertidal at Natural Bridges, are all females. The limpets are very territorial: when immersed at high tide they will cruise over the area that they monopolize and push or scrape off any interlopers such as other limpets, barnacles, or newly settled larvae.

An owl limpet (L. gigantea) in her farm at Natural Bridges
7 March 2017
© Allison J. Gong

See those zig-zaggy marks no the rock in the photo above? The owl limpet is also a farmer. As she’s patrolling her territory she uses her radula to scrape off the film of algae that grows on the rock. It takes a while for the algal film to develop, so the limpet restricts her grazing to one area at a time. She is, in effect, manipulating her environment to produce food. When humans do this we call it agriculture. Why not use the same term when a snail does it?

These Lottia farms are exactly the kind of thing that people overlook, and even stand in, without noticing that they are there. In the intertidal, as in many natural places, you don’t really see what’s going on until you slow down, let yourself just be, and get your face down where your feet are. You might be surprised at how much you can see.

A different sort of hatching

Posted on by Allison J. Gong
Newborn bald sculpin (Clinocottus recalvus) hatchlings
22 February 2017
© Allison J. Gong

My bald sculpins have begun hatching! Their egg mass has been disintegrating over the past few days and I couldn’t tell if that was because they were dying or hatching. Yesterday I was able to spend some time looking at them and was surprised to see that a few little pink blobs had wiggled their way out of the egg mass while I was manipulating it. Baby fishies! Well, they’re still mostly yolk, but each yolk has a baby fish attached to it. They flit around quite a lot and are difficult to photograph. I had to put this trio in a depression slide, the macro photographer’s trick of making the universe smaller so the creature can’t swim too far away.

Bald sculpin (C. recalvus) hatchling
22 February 2017
© Allison J. Gong

This little fish was cooperating with me, so I carefully placed a coverslip on its drop of water and took some video. The first part was shot through the dissecting microscope with epi-illumination from a fiber-optic light, which shows the surface details. The second clip was taken through the compound microscope with trans-illumination; this kind of lighting doesn’t show any of the three-dimensional structure of objects but does a wonderful job with transparent objects like larval fish.

I like that the baby fish have spots on their yolk sacs as well as the top of the head. And from the second half of the video it appears that they don’t yet have a gut, at least not one that I can see. For the time being they don’t need a gut, as they’re surviving off the energy stored in the yolk sac, but once the yolk has been absorbed they will have to start feeding. At that point they’ll need to have complete guts. I imagine they will be hungry, and hope I have something they’ll be able to eat.

How big are these baby fish, you ask? The smallest ones were about 2 mm long, and the biggest one was twice the size, with a correspondingly smaller yolk.

Bald sculpin (C. recalvus) hatchling
23 February 2017
© Allison J. Gong

And yesterday I caught some time-lapse video of a baby hatching from its egg. Why have I never played with the time-lapse function on my phone before? It’s really cool.

For now I’m keeping the babies in a mesh container, separated from their father so he cannot eat them. I don’t think I’ll end up with more than a couple dozen hatched larvae, as the egg mass has begun to decompose and many of the embryos have died inside their eggs. And no doubt some of the larvae that I’ve rescued already will die. I figure I have a few days before I need to worry about feeding the survivors. After that, who knows? Your guess is as good as mine.

Have a heart

Posted on by Allison J. Gong

Back in mid-December I collected a couple of small intertidal fishes and brought them back to the lab for observation and identification. Then the female laid a batch of eggs, which I’ve been watching ever since. Today the eggs are 15 days old. They are developing pretty quickly, I think, at ambient seawater temperatures of 12-13.5°C. Some of the changes can be seen with the naked eye, while others are visible only with some magnification.

Here’s a timeline of development for the first couple of weeks in the earliest life of bald sculpins.

Day 4: The egg mass is clean and the eggs are clear and pink. The very young embryo can be faintly seen as a paler pink strip lying on top of the darker pink yolk, which fills most of the internal volume of the egg. There are also some oil droplets associated with but not part of the yolk.

Eggs of the bald sculpin (Clinocottus recalvus)
3 February 2017
© Allison J. Gong

It wasn’t until this day that I was convinced the eggs were alive. Until then they looked like undifferentiated pink blobs with not a lot going on.

Day 7: Today they had eyes! And they were swimming around inside their eggs!

Eyed larvae of the bald sculpin (Clinocottus recalvus)
6 February 2017
© Allison J. Gong

Day 10: Today the eyes look more like fish eyes and are taking on a silvery sheen. Black pigment spots are forming along the dorsal surface of the embryos, and the yolk is noticeably smaller. The eggs are starting to look dirty to the naked eye, due to the darkening eyes and pigment spots.

Larvae of the bald sculpin (Clinocottus recalvus), age 11 days
10 February 2017
© Allison J. Gong

Today was the first day I could see their heartbeats! It was surprisingly difficult to capture the beating hearts with the camera.

Day 15: Some of the eggs have died, becoming opaque and hard. A few have broken open and are empty. The overall color of the egg mass is paler, as the larvae are consuming their yolks. The black pigment spots are becoming more prominent and seem to be concentrated on the top of the head.

Larvae of the bald sculpin (Clinocottus recalvus), age 15 days
14 February 2017
© Allison J. Gong

They look like baby fish now! They’re still flipping around inside their eggs and I think may be responding to light. They don’t seem to like it when I shine the light on them.

I’ve put together a short video of the eggs at various stages of development so far.

Let me know what you think!

Eggs of a different sort

Posted on by Allison J. Gong

Back in mid-December I collected some urchins at Davenport Landing. Some of these urchins are the parents of the larvae that I’m culturing and observing now. Towards the end of the trip I flipped over some surfgrass (Phyllospadix torreyi) and saw two fish, obviously sculpins, huddled together; they had been hiding in the Phyllospadix and waiting to be submerged when the water returned with the high tide. I have a probably inordinate fondness for intertidal fishes, and love catching sculpins. These were too big to be fluffies (Oligocottus snyderi) but I couldn’t pin down an ID any closer than that. I brought them back so I could take a closer look at them in the lab.

Trying to key out the intertidal sculpins in California is an activity fraught with danger. There are about a dozen species that are likely, plus more that are occasionally encountered in the intertidal. When identifying fishes ichthyologists use meristics, or counts of things such as scales along the lateral line or hard spines in the dorsal fin, to differentiate species. Since you can’t very easily count the number of spines in the dorsal fin while observing a fish thrashing around in a ziploc bag, I needed to get them under the dissecting scope.

Here is a picture that I took of the fish this morning. This is the same posture they had when I first saw them in the field. I think the male (paler fish on the right) is guarding the darker female. Oh, and while I’m at it, I should say that skin color is an unreliable characteristic to use when IDing sculpins. Their skin color can and does change very rapidly, depending on the surroundings and the fish’s emotional state.

3 February 2017
© Allison J. Gong

See those little tufts on the top of the head of the fish on the left? Those are called cirri. When I was keying out these guys I narrowed down the options to either bald sculpin or mosshead sculpin, and the distribution of the cephalic cirri was the final determining factor. Mosshead sculpins (Clinocottus globiceps) have cirri densely scattered over the entire head, while in balds (Clinocottus recalvus) the cirri extend forward only to just behind the eyes; in other words, bald sculpins have no cirri between the eyes or anywhere anterior to the eyes. In my fish the cirri clearly do not extend forward of the eyes, making these bald sculpins.

Bald sculpin (Clinocottus recalvus) peering at the camera with justifiable suspicion.
3 February 2017
© Allison J. Gong
Bald sculpin egg mass
3 February 2017
© Allison J. Gong

It usually takes animals a week or two to settle in after being collected from the field. After a couple of weeks the fish were eating regularly and hungrily. Sculpins don’t have an air bladder, which helps keep them from getting washed out of their home pools as the tide moves in and out, and tend to sink if they aren’t swimming. They can, however, swim very well. Once they got used to the idea of food coming at them from above they would start looking up when I removed the lid to their tank. When they’re really hungry they will swim up and attack the food, ripping it from my forceps. Otherwise I dangle food in front of their faces and they take it a little more gently. Now they are both eating well.

One of the sculpins went off its feed last week and then surprised me by producing a mass of pink eggs. She had deposited the eggs on the underside of the cover instead of on the surfgrass I have in the tank. No wonder she hadn’t been eating; with all those eggs inside her there would be no room for food! I decided to keep the eggs and see what, if anything, would happen with them.

Eggs of the bald sculpin (Clinocottus recalvus)
3 February 2017
© Allison J. Gong

Each of the eggs is about 1mm in diameter, and they are indeed pink. They are stuck together in a pretty firm mass. I peeled it off the cover of the tank and the whole mass remained intact. I can easily pick up the mass and put it into a bowl for viewing under the dissecting microscope. At first I could see that the eggs contained a large yolk and some smaller oil droplets but I couldn’t tell whether or not they were alive. I cleaned them off to remove any dirt or scuzz, then returned them to the tank, hoping the parents wouldn’t eat them. Over the first several days I couldn’t see any change in the eggs except some of them became opaque and white, obviously dead. And it looked like maybe the stuff inside the eggs was shifting around a bit, but I wasn’t sure if that was something good going on or the beginning of decomposition. The egg mass continued to stick together, though, which I took as a positive sign.

Then yesterday when I looked at the eggs I was able to convince myself that, yes, something is happening inside them. I saw tiny little fish bodies, complete with bulbous rudimentary heads, developing on the yolks!

Developing bald sculpin (C. recalvus) embryos
3 February 2017
© Allison J. Gong

Each egg is a pale pink sphere containing a darker pink yolk. At this early stage of development the yolk takes up most of the interior space of the egg. Lying across the yolk, with a swelling at one end, is the developing fish embryo. The swelling is the head. Even at this stage the three body axes (anterior-posterior, dorsal-ventral, and left-right) have been established for quite a while. The yolk will shrink as the energy stores within it are consumed by the developing embryo. I don’t know if sculpins hatch as larvae (i.e., with a yolk sac still attached) or as juveniles (after the yolk sac has been completely consumed). I hope I get to watch these eggs and see!

You can’t push a string

Posted on by Allison J. Gong

Northern California is currently being pummeled by a meteorological phenomenon called an atmospheric river. The storms produced by these “rivers” tend to be warm and can be very wet, such as the Pineapple Express storms that carry atmospheric moisture from Hawai’i to California. The weather station on the roof of our house has recorded 4.26 inches of rain over the past three days, and more will come in the next few days. In addition to the rain, the atmospheric river has brought very strong winds, gusting to 40+ mph. Combined with the saturated ground, winds like this can uproot trees and utility poles. So far we haven’t lost power, but are prepared with candles, firewood, and extra water. . . just in case.

Data from our weather station in Santa Cruz, CA.
8 January 2017

I am not a meteorologist, and this is not a blog about weather. I mention all the rain because it brought out the worms. Earthworms, to be more precise.

Earthworms are oligochaete worms in the phylum Annelida, which also contains the polychaetes (marine segmented worms) and hirudineans (leeches). The body plan for annelids is based on segmentation, or metamerism. Let me explain what that means.

Imagine a round water balloon. Now imagine two sets of rubber bands encircling the balloon along perpendicular axes. You’d have something like this:

where the green and red lines indicate different muscle types. Remember that we’re discussing a three-dimensional object here. We’ll call the red lines circular muscles, and the green lines longitudinal muscles. Now picture in your mind what happens when the circular muscles contract; how does this change the shape of the water balloon? What happens when the longitudinal muscles contract?

An annelid’s body consists of many fluid-filled segments, each with its own set of circular and longitudinal muscles. The segments are arranged along the anterior-posterior axis, with the head being located at the anterior end.

Adjacent segments are separated by a layer of tissue called a septum (anatomically speaking, a septum is any tissue that divides a cavity into two or more smaller spaces; think of the septum that divides your nasal cavity into left and right nostrils). An incidental amount of fluid may escape from one segment into the next, but for the most part they function as separate water balloons. Water isn’t compressible but is deformable, so contracting muscles around one part of the water balloon simply displaces that water to another part, and the balloon’s shape changes. Because each segment in our worm has its own complement of body wall musculature, its shape can be modified independently from that of its neighbors.

Rather than draw up another pedagogical worm, I’ll show you a real one. As I mentioned earlier all the recent rains have brought the earthworms out from their burrows. I was out and about myself this afternoon, and took pictures. This is the anterior (front) end of a worm. Not much of a head, is there? Earthworms are poorly cephalized, which makes sense when you consider that they live underground: an animal that spends almost all of its time in complete darkness has no need for eyes, and having sensory organs hanging off the body would impede its burrowing activities.

Earthworm on wet pavement.
8 January 2017
© Allison J. Gong

That pale pink apparently unsegmented bit of worm is the clitellum, a glandular structure used in reproduction. Another feature you can see is the difference in size among all the segments. Some of them are much wider than others. These are the localized deformations. The anterior-most segments are the widest; which type of muscle is contracted in this part of the worm? Which muscles are contracted in the segments immediately in front of the clitellum?

Earthworm on wet pavement.
8 January 2017
© Allison J. Gong

The annelid body plan originally evolved to facilitate burrowing through soft substrates. The fluid in each segment provides a stiffness against which the body wall muscles can contract, and the separation of adjacent segments allows the aforementioned localized deformations. An earthworm burrows by making its front end long and pointy (by contracting the circular muscles), jabbing it into the soil, swelling those anteriormost segments (by relaxing circular muscles and contracting longitudinal muscles), and pulling the rest of the body along. Next time you have a live earthworm at your disposal, watch how it moves either on top of or through the ground.

As you may imagine, while an earthworm’s body volume remains constant, its shape varies greatly. This has consequences for internal anatomy as well. For example, an earthworm’s gut is essentially a straight tube within a tube; it doesn’t have distinct compartments or side chambers as ours does. But it can’t really be straight, can it? If the overall body shape of an individual worm can change as much as we see in a burrowing earthworm, it follows that the internal morphology must be equally plastic. This means that the blood vessels and major nerve cord remain functional whether the worm is stretched out or scrunched up. Kinda hard to imagine that in the body of any vertebrates.

Does the title of this post make any sense now?

Seashore to forest

Posted on by Allison J. Gong

I am fortunate to live in a place of great natural beauty. While the Pacific Ocean dominates much of the landscape, we are also partially surrounded by mountains. I grew up in the flatness of the San Joaquin Valley, a couple hours’ drive from both the sea and the Sierra Nevada but not near enough for either to have any appreciable effect on daily life. When I first moved here from the Sacramento area to start graduate school, I felt claustrophobic because I had been used to looking out in any direction and being able to see for miles around. I’ve long since grown accustomed to the fact that the only miles-long vistas we get are over the ocean and have come to appreciate the proximity of the mountains.

Here we are ideally situated so that ocean and mountain forest are close enough that both can be explored in a single day. And in fact, I did just that the other day, on Boxing Day. The elephant seal (Mirounga angustirostris) breeding season has started, and I wanted to go up to Año Nuevo State Park to see them. Alas, this idea didn’t occur to me soon enough to purchase tickets for the docent-led tour to the elephant seal reserve area, so we didn’t get close to the seals. But it was a gorgeously clear day and the scenery was every bit as spectacular as you’d expect from this part of the coast.

Año Nuevo Island lies a short distance to the southwest off Año Nuevo Point and is reachable only by kayak. The island is a marine wildlife refuge closed to the public, uninhabited by any humans except scientists. Elephant seals, northern fur seals (a type of otariid, or eared seal), rhinoceros auklets, western gulls, and Brandt’s cormorants all breed on the island. California sea lions don’t breed on the island, but several thousand use it as a haul-out site throughout the year. During the elephant seal pupping season white sharks come to the waters around the island to feed on pups as they learn how to swim.

Año Nuevo Island, viewed from Cove Beach at Año Nuevo State Park.
26 December 2016
© Allison J. Gong

It is not common for the air to be so clear. Usually there is fog or haze that obscures the buildings. There used to be a lighthouse on the island; the dilapidated tower was pulled down in the early 2000s to safeguard the wildlife. Some of the other buildings–a 19th century residence and foghorn station–are currently used as research facilities.

View to the west from Cove Beach.
26 December 2016
© Allison J. Gong

Even without a ticket for docent-led tour of the elephant seal reserve area, you can hike to the staging area from where the tours depart. The trail passes a freshwater pond that is home to two endangered California herps: The red-legged frog (Rana draytonii) and the San Francisco garter snake (Thamnophis sirtalis tetrataenia). Years ago I had a colleague in graduate school who studied the elephant seals up at Año Nuevo. I went in the field with him one day and got to wear the special blue research windbreaker. He told me that before being allowed to drive into the reserve area all of the researchers have to take a driving test that involves not running over plastic snakes that are placed in the road. This is to make sure that the endangered snakes won’t be inadvertently killed.

Freshwater pond at Año Nuevo State Park.
26 December 2016
© Allison J. Gong

We ate lunch at a lookout point of the tour staging area. Because the air was so clear we could see quite a way down the coast. Highway 1 as it passes under the cliffs immediately north of the Waddell Beach is visible at the far right edge of the photograph.

View towards Waddell Beach from Año Nuevo.
26 December 2016
© Allison J. Gong

After lunch we headed away from the coast and drove up Gazos Creek Road a few miles into the forest. It took all of about 15 minutes to go from beach to redwood forest. How cool is that? Two completely different ecosystems to explore easily within a day. Even the weather was different: sunny and warm at the beach, much cooler and damper among the trees.

Although we were up in the redwoods, this day I was fascinated by all of the moss growing on the trees. We’ve had a decent amount of rain so far, and the forests are satisfyingly wet and squishy. The creek we followed had washed out a bit of the road in a couple of places, and was closed to all traffic about 5 miles from the highway.

Moss-covered tree along Gazos Creek.
26 December 2016
© Allison J. Gong

We didn’t have a lot of time to poke around in the forest, but since we were in the area we stopped at Rancho del Oso on our way home to visit my favorite tree. Rancho del Oso is at the bottom of Big Basin Redwoods State Park. I take my ecology students there for the first field trip of the semester, because there I can introduce them to two of the ecosystems that define the natural history of Santa Cruz.

My favorite tree is a coast live oak (Quercus agrifolia) that lives just off the trail at Rancho del Oso. I love its gnarled branches that grow horizontally at ground level. It is an old, wise tree. Looking through its branches you see into the redwood forest of Big Basin. I normally photograph this tree at a different angle, looking into the forest away from the trail. This day I decided to shoot it from an angle parallel to the trail. I don’t think it’s quite as dramatic from this angle but there’s no denying the magnificence of the tree.

Coast live oak (Quercus agrifolia) at Rancho del Oso.
26 December 2016
© Allison J. Gong

Rancho del Oso is also the downhill terminus of the Skyline-to-the-Sea trail. The entire trail is about 30 miles, and most hikers take two or three days to hike the whole thing. I’m not much of a backpacker but one of the things I’d like to do this spring is the day hike from Big Basin down to Rancho del Oso. Doesn’t that sound like great fun?

Green Friday

Posted on by Allison J. Gong

In recent years the day after Thanksgiving has become known as Black Friday, a day when retailers across the nation offer fantastic sales in order to separate Americans from their hard-earned cash. I hate shopping even under the best of circumstances, and you couldn’t pay me enough to step foot in a shopping mall on Black Friday. Fortunately, a trio of organizations have put together about the most awesome alternative to Black Friday that I could imagine. They call it Green Friday.

The idea behind Green Friday, as I understand it, is to get people to spend the day after Thanksgiving outdoors enjoying nature instead of fighting over $5 t-shirts at some big department store. The three organizations–Save the Redwoods League; the California State Parks Foundation; and the California State Parks–sponsored some number of free parking passes at the state parks. I have a Golden Poppy pass, which gets me into state parks in northern California and we didn’t need one of the free passes, but I’ve been wanting to go hiking up in Big Basin so I rounded up my husband and a few friends and off we went.

Big Basin Redwoods State Park is the oldest state park in California, established in 1902. It has long been my favorite of the state parks I’ve visited.

Big Basin sign

I have to say, the Green Friday thing seemed to be working. The park was very crowded, with lots of families. We chose to hike the Sequoia Trail, a 4-mile loop that begins at the park headquarters and goes past Sempervirens falls, a monument to the founders of the park, and a treacherous passage called Slippery Rock. The oldest and tallest redwood trees in the park are seen from the Redwood Loop trail, which we didn’t hike this time. But it is impossible to see any redwood forest, and not feel awed.

Redwood forest in Big Basin Redwoods State Park. 25 November 2016 © Allison J. Gong
Redwood forest in Big Basin Redwoods State Park.
25 November 2016
© Allison J. Gong
Looking up at redwood trees (Sequoia sempervirens) in Big Basin Redwoods State Park. 25 November 2016 © Allison J. Gong
Looking up at redwood trees (Sequoia sempervirens) in Big Basin Redwoods State Park.
25 November 2016
© Allison J. Gong

The oldest of these trees have outlived multiple human civilizations. It’s humbling to be surrounded by such ancient beings.

The forest floor is shaded by the canopy of the redwood and other tall trees. At this time of year, and especially after a rain, the understory is spectacular with greenery and life. It’s all about the mushrooms. California had four dry winters before last year’s El Niño rains, and so far this autumn has been fairly wet. Well, October was wet; we didn’t have rain in November until last weekend. The fungi have been biding their time, waiting for enough water to fall from the sky before sending up their fruiting bodies. Now, I freely admit that mushroom identification is a major weak spot of mine, so take these names with a grain of salt. But I’m learning! The duff on the ground in the area we hiked was a mixture of redwood needles and leaves from tan oak (Notholithocarpus densiflorus) and California bay laurel (Umbellularia californica). Many mushrooms were growing directly through the duff, while others were growing on living or dead trees.

Ramaria sp. in the redwood forest in Big Basin Redwood State Park. 25 November 2016 © Allison J. Gong
Ramaria formosa(?) in the redwood forest in Big Basin Redwood State Park.
25 November 2016
© Allison J. Gong

This so-called coral mushroom is, I think, Ramaria formosa. We saw a few clumps of it right at the beginning of the hike, in this pale orange color. The branching at the tips appears to be more or less dichotomous, and the overall shape and size of the body reminded me of the intertidal rockweed Pelvetiopsis limitata.

These really pretty bracket fungi may be turkey tails (Trametes versicolor). We found lots of them on both dead and living trees. The ones that are brilliant orange and brown I do recognize as turkey tails, but when they’re pale and creamy like these I’m not sure whether or not they’re the same thing.

Bracket fungus (Trametes sp.) growing on a dead log.
25 November 2016
© Allison J. Gong

And there were spectacular displays like this:

25 November 2016 © Allison J. Gong
25 November 2016
© Allison J. Gong

and this:

25 November 2016 © Allison J. Gong
25 November 2016
© Allison J. Gong

and this:

25 November 2016 © Allison J. Gong
25 November 2016
© Allison J. Gong

and strange things like this:

25 November 2016 © Allison J. Gong
25 November 2016
© Allison J. Gong
Clavaria fragilis, or fairy fingers 25 November 2016 © Allison J. Gong
Clavaria fragilis, or fairy fingers
25 November 2016
© Allison J. Gong

I was able to identify those strange white things as Clavaria fragilis, or fairy fingers. The mycelium of this fungus lives underground in grasslands and wooded areas; it is described as common in this area, especially during the wetter months. The arrangement of these fruiting bodies in a more or less straight line is interesting and makes me wonder if the mycelium is living in a log buried under the duff. I don’t know what else would cause the mycelium to grow in such a linear fashion.

My favorite mushroom photo of the day was of these LBMs (little brown mushrooms) that were growing out of a downed redwood. The mushrooms themselves are extremely cute, but what I really like about this picture is the bokeh. I’ve become intrigued by the practice of composing and exposing photographs so that the the non-subject matter is deliberately blurred and becomes part of the overall aesthetic quality of the image. I think I’ve noticed it before, but never really thought about how to achieve it. Practicing it is a whole lot of fun, and I think there will be many more photos like this in my future.

LBMs (little brown mushrooms) growing on a redwood log 25 November 2016 © Allison J. Gong
LBMs (little brown mushrooms) growing on a redwood log.
25 November 2016
© Allison J. Gong

Where there are mushrooms there are mushroom predators such as banana slugs. I think we counted about 10 of the bright yellow gastropods on our hike. Alas, none of them were copulating. But one of them was eating a mushroom!

Banana slug (Ariolimax sp.) eating a mushroom. 25 November 2016 © Allison J. Gong
Banana slug (Ariolimax sp.) eating a mushroom.
25 November 2016
© Allison J. Gong

What a great afternoon it was! Given how crowded the park was I’d say that Green Friday was a success. I’d so much rather see people hiking or at least spending time outdoors than shopping for material things. I hope that Green Friday is here to stay!

Why does the ocean stink?

Posted on by Allison J. Gong

Several people in the past few days have asked me why the ocean stinks. The answer is simple. The red tide that I documented a month ago is back, and worse than ever. The culprit is the same, but now it is present in even higher numbers. I can’t show you how it smells, but this is how it looks:

The brown discoloration is due to the high concentration of the dinoflagellate Akashiwo sanguinea. Since the marine lab brings water directly from right about where the waves are starting to crest, our water is also full of the cells. Water coming straight from the taps is tinged with brown, and filters clog like crazy. Animal care has been redefined as “flush, brush, and refill,” as in flush tables, brush or spray globs of brown slime off the animals, and refill the tanks. Only with the water coming in brown, the Akashiwo cells start settling out almost immediately.

This latest bloom of A. sanguinea coincides with the first storm of the rainy season, which could be either good or bad. The first rain causes a big influx of nutrients from land into the ocean–this is good for the blooming dinoflagellates because nutrients are fertilizers. But rain storms come from clouds, and the reduction of sunlight would be bad for photosynthetic critters such as Akashiwo. So what’s it going to be?

Akashiwo sanguinea isn’t a toxin-forming species. However, it does form surfactants when the water is agitated, and the surfactant can be irritating.

Bloom of the dinoflagellate Akashiwo sanguinea at the mouth of Younger Lagoon. 15 October 2016 © Allison J. Gong
Bloom of the dinoflagellate Akashiwo sanguinea at the mouth of Younger Lagoon.
15 October 2016
© Allison J. Gong

See all that foam? When a strong breeze picks up the foam you can smell it. Imagine the smell of rotting kelp, perhaps not quite that pungent, combined with a vague hint of sewer. That doesn’t look quite right but it’s the best I can do. Since I can’t share it with you here, you’ll have to go to the beach and smell it for yourself.