This week I took my Ecology students to the Younger Lagoon Reserve (YLR) on the UC Santa Cruz Coastal Science Campus. The YLR is one of 39 natural reserves in all of the major ecosystems throughout the state of California. The UCSC campus administers five of the reserves: Younger Lagoon, the Campus Reserve, Fort Ord Natural Reserve, Año Nuevo (operated in conjunction with the California State Park system), and the Big Creek Natural Reserve in Big Sur. The UC reserves are lands that have been set aside to use as living laboratories and outdoor classrooms, and are fantastic places to take students to learn about the natural history of California. They provide students with opportunities to gain valuable hands-on experience working in the field, through classes, internships, or volunteering.
The Younger Lagoon Reserve comprises about 70 acres of land, most of which was formerly brussels sprouts fields. The lagoon itself is a Y-shaped body of brackish water that receives input from run-off due to rain. It connects with the water of Monterey Bay only when there is enough freshwater flowing to break through the thick sand berm; this happens once or twice a year during the rainy season. The Lagoon lands were donated to UCSC in the 1970s. East of the actual lagoon are about 47 acres of what are referred to as Terrace Lands, which were incorporated into the YLR in 2009. This is where, for the past three years, I've brought students to work on vegetation restoration. The team of reserve stewards, interns, and volunteers has a yearly goal to replant two acres every year.
This year, instead of getting straight to the planting, we began the morning at the bird banding station. Personnel at the YLR have been banding birds for a little over a year now, usually on Fridays and occasionally on Thursdays. The banders, or "bird nerds", get started at about 07:30, and by the time our class arrived at 09:30 they had caught five birds. It was windy and there was no cloud cover at all, which were not very good conditions for catching birds in either the mist nets or the ground traps.
Notice how both the mist net and the ground trap are empty? That's the kind of luck we had with the bird banding.
The rest of the morning was very productive. After the bird banding demonstration we joined the UCSC student interns on the Terrace Lands for some planting. The method used for planting has changed since the last time I was here with students in 2016, due to a 5-year study comparing weed control methods. Herbicide was very effective, but obviously toxic to the native plants as well as the weeds. The stewards also tried laying black plastic over the fields and letting the sun bake the weeds to death. This was almost as effective as herbicide; however, the plastic can be used only a few times and then has to be thrown away to end up in the landfill. The result of the study was a compromise between effective weed control and minimal negative environmental impact. The planters now put down a layer of biodegradable paper and cover it with mulch. Holes are punched through the paper and small plants are planted in the holes. The combination of the paper and mulch seems to work pretty well. Plus, there's no waste!
A large group of about 25 motivated workers can accomplish quite a lot in a few hours. By lunchtime we had lain three long strips of the paper side-by-side, covered them with mulch, and repeated the process twice more, using up the entire roll of paper. The hole-punching and planting go more slowly, but we did place ~200 plants in the ground. It was a busy and productive morning, despite the lack of birds. The students said they learned a lot and had fun doing it. That's the beauty of field trips!
This week's field trip for my Ecology class was the first of two visits to the Santa Cruz harbor. The students' task was to select a site to monitor for a semester-long study of ecological succession. The floating docks at the harbor are the ideal site for this kind of study because I know from experience that the biota changes from season to season throughout the year, on a time scale that can be observed within the confines of a 16-week semester. We will return to the harbor in nine weeks and students will document how their sites have changed in that time.
California is swinging back into the severe drought situation we had before the epic 2016-2017 rainy season. Since the current rainy season began on 1 October 2017, we've had hardly any rain at all and very little snow in the Sierra. Fools who thought that one rainy season would get us out of drought are just that--fools. However, one nice thing about drought conditions is that visibility at the harbor is pretty good. Without any significant runoff the water is nice and clear, making it easy for the students to see what's growing on their section of the docks.
The assignment for this first visit to the harbor was to choose a site, identify what lives on the site, and draw a map of it. I had warned them that all the interesting biology on the docks occurs below the level of their feet, and that they would have to lie or kneel on the dock to get a good look at what's going on down there. Some of them tried to take a photo of the entire site, but it's impossible to get far enough away. Unless you're actually in the water, from where it would be easy. Yeah, you could don a wetsuit and get in the water, but the harbor isn't the most ideal place to go for a morning swim.
A little back story on the docks at the Santa Cruz harbor
Remember the magnitude 9.0 earthquake and subsequent tsunami that occurred in northern Japan several years ago? That was on 11 March 2011 at 14:46 local time. That morning in Santa Cruz we received a tsunami warning. I didn't venture down to the harbor (I think I was working at the marine lab that day) but here's a video shot by a woman who watched the ~0.5 meter tsunami tear through the upper harbor:
Amazing, the destructive power of such a small wave, isn't it? Boats were wrenched from their moorings and slammed into other boats and harbor infrastructure. I forget the total dollar amount of damage that our harbor sustained, but as a result all of the docks were replaced in the next few years. I did happen to be at the harbor with a group of students on one of the days that the old docks were being removed. It was heartbreaking to see the docks, carrying decades of biological growth on them, dumped in the parking lot to dry out in the afternoon sun. I imagine they were eventually hauled out to the landfill.
Since then, the biota on the new floating docks seems finally to be stabilizing. If I had been teaching Ecology back in 2013, we would have had pristine habitat in which to observe honest-to-goodness primary succession. As things are, however, I'm giving students the option of scraping all or part of their plot clear, to simulate primary succession. Their other option is to leave the plot as-is, and pick up the succession process somewhere in the middle and see what happens from this point forward.
So, what did they see down there?
Well, even though the water was relatively clear, a lot of the photos looked like this:
I can identify much of the stuff in this photo, but this isn't the best shot to showcase the biodiversity on the docks. I decided that the camera would do a better job if I used it to photograph individual organisms instead. Here are some of my favorites.
This shot is looking straight down along the edge of one of the docks. The macroscopic life begins 2-3 cm below the waterline, and even above that the dock surface is covered with microscopic scuzzes.
I had shown the students pictures of organisms they would be likely to see at the harbor. One of the critters that shows up sporadically is the introduced hydroid Ectopleura crocea. Later in the semester we will discuss species introductions and invasions in more detail. Harbors generally tend to be heavily populated by non-native species, and our local harbor is no exception. The species of Ectopleura found in harbors has hydranths that can be 8-10 cm long, and when it occurs it tends to be quite conspicuous. The congeneric species, E. marina, lives in intertidal in some areas on the open coast; I've seen it in a few tidepools at Davenport Landing, for example. The intertidal species is much smaller, about 2-3 cm tall and doesn't form the dense clumps that typifies E. crocea.
The ubiquitous caprellid amphipods were crawling all over everything, as usual. Some of the students really didn't like these guys and one of them had the same reaction to them that I do, which is a general shudder. They're sort of cute in still photos, but when they start inchworming around they look sort of creepy. And when there's a bunch of them writhing around in an oozy mass, they're REALLY creepy.
One of the most conspicuous worms at the harbor is Eudistylia polymorphora, the so-called feather duster worm. They come in oranges, purples, and yellows. This one was pure white. Lovely animal!
Tube-dwelling polychaete worms, such as Eudistylia, don't have much in the way of a head but they do have many light-sensitive eyespots on the tentacles. They react very quickly to many stimuli, and even a shadow passing over a worm causes it to yank its tentacles into its tube in the blink of an eye. Usually they're not too shy, though, and will extend their tentacles soon to resume feeding.
All told we were on the docks for about 2.5 hours. Not a bad way to spend a glorious morning, is it?
The intertidal portion of my participation in Snapshot Cal Coast 2017 is complete. I organized four Bioblitzes, two of which consisted of myself and Brenna and the other two for docents of the Seymour Marine Discovery Center (Tuesday) and the docents of Año Nuevo and Pigeon Point State Parks (Wednesday). The four consecutive days of early morning low tides have been exhausting for a concussed brain and a body dealing with bronchitis for the past several weeks. Good thing the low tide arrives 40-50 minutes later, or I'd probably be dead by now. And even so, I tried to take advantage of the later tides to venture a bit farther afield, so I still ended up getting up at the butt-crack of dawn.
But oh, so totally worth it!
Day 3: Davenport Landing with docents from the Seymour Marine Discovery Center, Tuesday 27 June 2017, low tide -1.1 ft at 08:03
Davenport Landing Beach is a sandy beach with rock outcrops and a fair amount of vertical terrain to the north, and a series of flat benches (similar to those at Natural Bridges) to the south. To get to the good spots at the north end you have to do some cliff scrambling, unless the tide is low enough that you can walk around the rock, which happens maybe once or twice a year. Because it's easier to get around on the benches to the south, that's where I took my group for the Bioblitz. The difference in topography also results in some differences in biota and distribution/abundance of organisms; overall biodiversity is probably equivalent at both sites, but certain species are more abundant at one site versus the other.
The morning we went to Davenport was sunny and (almost) warm. This makes for plenty of light for photography, but also lots of glare of the surface of pools and the wet surfaces of organisms themselves. My most successful photos are the ones I took with the camera underwater. Wanting to improve my skills at identifying algae, I concentrated most of my efforts on them while not ignoring my beloved invertebrates.
Coralline algae are red algae whose cells are impregnated with CaCO3. This gives them a crunch texture that is unusual for algae. Corallines come in two forms, encrusting and upright, and can be one of the most abundant organisms in the high and mid intertidal. There are several species of both encrusting and upright corallines on our coast, and most of the time they aren't identifiable to species by the naked eye. Sometimes I can distinguish between genera for the upright branching species. However, the encrusting species require microscopic examination of cell size, crust thickness, and reproductive structures, none of which can be observed in the field.
Some algae are so distinctive that a quick glance is all it takes to know exactly who they are. With its tiny holdfast, long elastic stipe, and single large pneumatocyst, bullwhip kelp doesn't look anything like the other kelps in California. Like most kelps, N. luetkeana lives mostly in the very low intertidal or subtidal, where under certain conditions it can be a canopy-forming kelp. About a month ago I noted a big recruitment of baby Nereocystis kelps in the intertidal on the north side of Davenport Landing Beach. I speculated then that they probably wouldn't persist into the summer. I'll have to take a morning soon to go up and check on them. Anyway, on our Tuesday Bioblitz we found this big N. luetkeana growing in the intertidal. The stipe was about 1.5 meters long and the pneumatocyst was a little smaller than my closed fist. Given that this individual recruited to that spot and has persisted for a few months, probably, it has a good chance of continuing to survive into the fall. Winter storms, especially if they're anything like the ones we had this past year, will most likely tear it off, though.
Coralline algae aren't the only pink things in tidepools. There are pink fish!
Sculpins are notoriously difficult to ID if you don't have the animal in hand to count things like fin rays and spines. Someone on iNaturalist may be able to ID this fish, but I don't think the photo is very helpful.
And, just because they're my favorite photographic subjects in the intertidal, here's a shot of Anthopleura sola:
As of this writing, 10 participants in this Bioblitz have submitted 204 observations to iNaturalist, with 70 species identified. I know that some people haven't upload their observations yet, and expect more to come in the next couple of weeks. The docents enjoyed themselves, to the extent that two of them accompanied Brenna and me to our fourth Bioblitz at Pigeon Point.
Day 4: Whaler's Cove at Pigeon Point with rangers (and one docent) from Pigeon Point and Año Nuevo state parks, Wednesday 28 June 2017, low tide -0.6 ft at 08:53
Usually when I go to Pigeon Point I go to the north side of the point, either scrambling down the cliff next to the lighthouse or about half a mile north to Pistachio Beach. When the park rangers and I were organizing this Bioblitz they suggested going to Whaler's Cove, as the access is very easy due to a staircase and would be much easier for docents who aren't used to climbing down cliffs. It ended up being a good decision, as there was much to be seen.
Bioblitzes and iNaturalist are all about photographing individual organisms (as much as possible) so that they can be ID'd by experts in particular fields. This is the 'tree' level of observation I mentioned in my previous post. I find that when I'm taking photos with the intent to upload them to iNaturalist the photos themselves tend to be rather boring. The intertidal is such a dynamic and complex habitat that photos of single species tend to lack the visual interest of the real thing. I've learned that one of my favorite things to see is organisms living on other organisms.
See what I mean?
Four of this chiton's eight shell plates are completely covered with encrusting coralline algae. It is also wearing some upright corallines and at least two other red algae, one of which is Mastocarpus papillatus. This photo produced six observations for iNaturalist.
Which is not to say that single-subject photos are always boring. When the subject is as weighty as this gumboot chiton (Cryptochiton stelleri), it deserves its own photo or two.
The largest chiton in the world, Cryptochiton typically lives in the subtidal or the very low intertidal. Unlike other chitons, it doesn't stick very firmly to the substrate. I was able to reach down and pick up this one with very little effort. In the subtidal this lack of suction isn't a handicap, as water movement there is less energetic compared to the intertidal, and Cryptochiton does quite well. But it doesn't really look like a chiton at all, does it? That's because its eight dorsal shell plates are covered by a thick, tough layer of skin called the mantle. In most chiton species the mantle is restricted to the lateral edges of the dorsal surface. The girdle, as it's called, exposes the shell plates to some degree. We don't see Cryptochiton's shell plates, but if you run your finger down the middle of the dorsum you can sort of feel them underneath the mantle.
Okay, now for some more 'forest' pictures.
I love this one. There's a lot going on in this small area. The greenish-brown algae are actually a red alga, Mazzaella flaccida. There are two large clumps of stuff in the photo. The clump on the left, consisting of round lumps, is a clone of the aggregating anemone Anthopleura elegantissima. The other clump is a mass of tubes of the polychaete worm Phragmatopoma californica. These two clumps were formed in very different ways, reflecting the vastly different biology of the animals that made them.
Anthopleura elegantissima is one of four species of Anthopleura anemones we have in California and is the only one to grow by cloning. It does so via longitudinal fission, in which an anemone literally rips itself in half. I wrote about them last year. Note that in this aggregation, all of the anemones are about the same size. That's because they're all clones of each other and share the exact same genetic makeup.
Whereas a clone of A. elegantissima represents a single genotype formed by cloning, clumps of Phragmatopoma arise by gregarious settlement. Each of the tubes in a clump is occupied by a single worm, which recruited to that spot as a larva and settled down to live its life. When it comes time to look for a permanent home, the planktonic larvae of Phragmatopoma are attracted by the scent of adult conspecifics. The larvae settle on the tubes of existing adults and undergo metamorphosis. Each worm builds its tube as it grows, using some kind of miraculous cement that sticks sand grains together, much as a mason stacks bricks to build a wall. One of the remarkable things about this construction is that the cement is secreted by the animal's body and starts out sticky and then hardens, all in seawater. It's a likely candidate for Best Underwater Epoxy around. Interestingly, Phragmatopoma can build its tube only as a growing juvenile. Adult worms that are removed from their tubes do not build new ones, and soon die.
Here's another nice clump of Phragmatopoma:
See that pile of rocks out there? That's where we were blitzing. Given the not-so-lowness of the tide I didn't know if we would be able to make it out there. We were lucky, though, and were able to spend ~30 minutes out on that little point.
So far, the Pigeon Point Bioblitz has yielded 204 observations for iNaturalist, with three participants (so far!) identifying 77 species. Several of my observations were of red algae that I did not recognize; hopefully an expert will come along to ID those for me. Snapshot Cal Coast 2017 continues through this weekend. My intertidal Bioblitzes are over, but I hope to contribute one last set of observations by collecting and examining plankton on Sunday.
Since 2000 the first Saturday in May is Snapshot Day in Santa Cruz. This is a big event where the Coastal Watershed Council trains groups of citizen scientists to collect water quality data on the streams and rivers that drain into the Monterey Bay National Marine Sanctuary, then sets them loose with a bucket of gear, maps, and data sheets. The result is a "snapshot" of the health of the watershed. As we did last year, my students and I were among the volunteers who got to go out yesterday and play in coastal streams. This year there were 13 (+1) groups sent out to monitor ~40 sites within Santa Cruz County. For reasons I don't entirely understand four sites in San Mateo County (the county to the north along the coast) were included in this year's sampling scheme; hence the +1 designation. Since I routinely haunt the intertidal in this region I took the opportunity to become more familiar with the upstream parts of the county and volunteered to sample at these northern sites. It just so happened that I was teamed with two of my students, Eve and Belle, for yesterday's activities.
Of our four sites, two were right on the beach and two were up in the mountains. Thus our "snapshots" covered both beach and redwood forest habitats. Here are Belle and Eve at our first site, Gazos Creek where it flows onto the beach:
After heavy rains the water draining through the watershed breaks through the sand bar and the creek flows into the ocean. Yesterday the sand bar was thick and impenetrable, at least to the measly amount of rain we'd had in the past 24 hours.
At each site we collected two water samples, for nutrient and bacteria analyses, and the following field measurements:
air and water temperature
dissolved oxygen (DO)
Here Eve is measuring conductivity in Gazos Creek (beach site):
Most of the equipment we used to take the field measurements was simple and straightforward: pH strips and a thermometer, for example. Even the conductivity meter was easy to use. You just turn it on, let the machine zero out, and stick it in the creek facing upstream so that water flows into the space between the electrodes. Here's Belle taking a conductivity measurement at our Gazos Creek (forest) site:
The only tricky field measurement was the one for dissolved oxygen (DO). This involved collecting a water sample (easy enough), inserting an ampoule containing a reactive chemical into the sample tube, breaking off the tip of the ampoule so that water flows into the tube, and gently mixing the contents of the ampoule for two minutes. Then you compare the color of the ampoule with a set of standards in the kit to estimate the DO level in mg/L (=ppm).
Our second and third sites were up in the mountains, at Old Woman's Creek and Gazos Creek (forest). With all the rain we had over the winter the riparian foliage has exploded into green. It was all absolutely lush and glorious. How lucky we were to spend the day in such surroundings!
And there were a great many banana slugs! All of them were solid yellow, with no brown spots. At one point there were so many slugs that we had to be extremely careful not to step on them.
Our fourth and final site was Whitehouse Creek, which flows into the Pacific Ocean to the south of Franklin Point. We had about a 10-minute hike to the creek from the road. By that point it had been raining for quite a while. Although we were protected from the rain by the trees when we were up in the forest, when we walked out to the field to the beach we were lucky it had eased to a light sprinkle.
After we finished our sampling we all agreed that we had to have gotten the most picturesque sites. None of the other teams got to visit both forest and beach for their sampling! We didn't drop off our samples and equipment until 14:00, a couple of hours later than the other groups, but who would complain about having getting to spend the day tromping through the forest AND the beach?
In recent years, citizen science has become a very important provider of biological data. This movement relies on the participation of people who have an interest in science but may not themselves be scientists. There is some training involved, as data must be collected in consistent ways if they are to be useful, but generally no scientific expertise is required. The beauty of citizen science is that it allows scientists and science educators to share the experience of discovery with people who might not otherwise know what it's like to really examine the world around them. I think it is a great step towards creating a less science-phobic society, one in which science informs policy on scientific matters.
LiMPETS stands for "Long-term Monitoring Program and Experiential Training for Students." The program seeks both to give students experience doing real science and to establish baseline and long-term ecological data for California's sandy shores and rocky intertidal areas. As an intertidal ecologist myself, I naturally wanted my students to participate in the rocky intertidal monitoring.
The LiMPETS coordinator for Santa Cruz and Monterey Counties is a woman named Emily Gottlieb. She and I decided to have my class monitor the site at Davenport Landing. Emily came to class two weeks ago to train the students in identifying the relevant organisms and recording the data.
Tidepooling is easy and comfortable when you do it inside a classroom seated at a table. But today was all about the real thing. It was overcast and breezy when we met up with Emily at 09:30 and headed out to the site. At first the students seemed to be a little skeptical about the whole thing.
We were extremely fortunate to be joined this morning by Dr. John Pearse, Professor Emeritus of Biology at UC Santa Cruz, one of my graduate advisors, and the founder of LiMPETS. Dr. Pearse has been monitoring some sites, including this one at Davenport Landing, since the 1970s. He is THE person to talk to about intertidal changes in California over the past 40 years.
Years ago John set up permanent transect lines and plots at Davenport Landing, marking the origin of each transect with a bolt. The first thing we had to do when we got to the site was find the bolt. Then John ran out the transect line to the lowest point that students could work safely, given the conditions of tide and swell; this happened to be about 15 meters.
For the vertical transect, 1/2-meter square quadrats were placed at each meter. Some organisms were counted as individuals and others were marked as either present or absent in each of the 25 small squares within each quadrat. Emily gave the students their assignments and data sheets, and they spread out along the transect line.
Aside from the experience of learning how to do this kind of data collection, I hope the students understand what a privilege it is to have been in the field with John Pearse. He has such a thorough understanding of the intertidal that he is a treasure vault of knowledge. Here he is explaining what owl limpets are all about:
Interestingly, we didn't find many owl limpets. And certainly not any of the big ones that I see all the time at Natural Bridges. John said that this is one of the differences between a protected area (Natural Bridges) and an unprotected one (Davenport Landing). Collecting is not allowed at Natural Bridges, and the owl limpets are left unmolested--by humans, at least--to grow large (10+ cm long is not uncommon). On the other hand, people do collect at Davenport and I've heard it said that owl limpets are good to eat; today we saw fewer than a dozen owl limpets and they were all small, none larger than 3 cm long.
The sun came out after a while, but the wind also picked up. The tide came up as well, and some of the students got more than a little wet. Overall they were real troopers, though, and I didn't hear much complaining. Next week is the last lab of the semester, and we'll be participating in another citizen science project. But that's a tale for another day.
I did take advantage of the beautiful setting to have one of Emily's LiMPETS volunteers (and a former student of mine!) take our class photo. Here we are, the Bio 11C class of 2016!