The Carmel is a lovely little river. It isn’t very long, but in its course it has everything a river should have. It rises in the mountains, and tumbles down a while, runs through shallows, is dammed to make a lake, spills over the dam, crackles among round boulders, wanders lazily under sycamores, spills into pools where trout live, drops in against banks where crayfish live. In the winter it becomes a torrent, a mean little fierce river, and in the summer it is a place for children to wade in and for fishermen to wander in. . . . It’s everything a river should be.
— John Steinbeck, Cannery Row
Every Spring semester when I teach my Ecology class, I try to develop a new field trip activity, or modify an existing one. Some activities I’ll probably always keep, either because they are really popular with the students or (more likely ‘and’) because I think they are good learning experiences, but I can also swap out some of the others if better options come along. There’s also some fine-tuning that occurs along the way, as I tweak things to improve what I hope is already a good field trip. As much fun as it is to play outside instead of being stuck in a classroom, the point of the field trips is to learn something about ecology–a new habitat, current research in particular fields of study, challenges to restoration and conservation, and the like. Since citizen science has become the catch phrase du jour in the first fifth of the 21st century, I feel that it is important to give students opportunities to participate in some of the science activities available to the wider community.
All of which explains why the students and I made the hour-long trip down to a location called Garland Ranch, on the Carmel River. Back in the fall I heard of a new project starting up in Monterey County, to monitor water quality along the Carmel River. The project, called Watershed Guardians, is operated from the Pacific Grove Museum of Natural History. Its goal is to protect steelhead trout in the river by measuring parameters that indicate suitability for the various life history stages of the fish. Like many programs of its kind, Watershed Guardians also has a secondary goal of getting students as young as middle-schoolers out of the classroom and into the field to do some real science. The two goals converge quite nicely, as a big part of the learning experience for the students is developing an understanding ownership of their local river and watershed. Hopefully that sense of ownership evolves into one of responsibility and stewardship. And it is a well-known adage that one way to get adults to care about something is to get their kids to care about it first, so all of these citizen science programs directed at school-age children have the benefit of attracting the attention of people old enough to vote and direct policy decisions. Win-win-win!
Our guide for the day was Matt, who works at the PGMNH and led the teacher training session I attended last fall. He met us at Garland Ranch, where we divided the class into four groups. Matt had arrived with two pairs of backpacks, each pair consisting of one light and one dark. The light and dark backpacks contained equipment and kits for different suites of tests. Each group of students would start with one backpack, either light or dark, and then swap with a different group when finished. That way every group ran all of the tests: pH, temperature, turbidity, DO (dissolved oxygen), alkalinity, and salinity. Some of the tests were quite simple, and others were more complicated.
The four sampling sites at the Garland Ranch location were close together near the vehicle bridge. We’ve had a lot of rain this winter and the river has been running high. As a result a lot of the sand had been washed away, making the beach fairly steep and rather narrow. To make matters even more difficult, the poison oak has been extremely crafty–its bare sticks are everywhere, looking totally innocent, encroaching on trails and twined around trees. It took some attention to make sure I didn’t brush up against any of it while moving up and down the beach.
The final step in the program is for the students to enter their data into the Watershed Guardians database. The whole point of the program is for these data to be shared publicly for all to use. It’s important for students to see the activity through to the end and to know that the work they did will actually be going somewhere. We’ll take care of that task next week!
The other day my students and I lucked out with the weather and managed to get in a full day of exploring a former military base. Fort Ord, on Monterey Bay near the small city of Marina, was an Army base until it was closed in 1994. Since then, most of the land (~14,600 acres) has been designated the Fort Ord National Monument, administered by the federal Bureau of Land Management. Smaller portions were transferred to the surrounding cities, the campus of CSU Monterey Bay, the state park system, and the University of California’s Natural Reserve system. Our guide for the day, Joe, is the reserve manager for the Fort Ord Natural Reserve, and had arranged for us to meet with researchers working at both sites that we visited. It really was a fantastic learning opportunity for all of us.
The Fort Ord National Monument (FONM) came into being in 2012–thank you, President Obama! Most of the monument is public land, with miles of trails used to hikers, bicyclists, and horseback riders. The monument is also home to the California tiger salamander (Ambystoma californiense), the central California population of which is federally threatened. The first person we met on our field trip was a guy named Robert, who is a graduate researcher working on conservation of the tiger salamanders. Robert showed us some artificial vernal pools that he’s using in his research.
The 18 pools are about 10 meters in diameter, lined with an impermeable layer, and were allowed to fill with natural rainwater. Robert’s plan is to seed them with salamander larvae and record how they survive and disperse from the pools. There’s a lot more to the story than that, but it’s Robert’s story to tell, not mine.
We did get to help Robert check the pitfall traps, which are arranged in pairs on each side of the fence surrounding each pool. Each trap is a small bucket set into the ground to be level with the surface. The lid is mounted on wooden legs and sits above the trap, to keep it from filling with water. Animals crawling along the fence will fall into the bucket. Robert collects data on the animals trapped and then releases them unharmed.
The tiger salamanders are all underground at this time of year so there were none in the traps. The students did, however, find a pair of western toads (Anaxyrus boreas) in one of the traps. They were in amplexus, which is what herpetologists call the mating position of frogs and toads: the male clasps the female around her body, ideally positioned to fertilize the female’s eggs as she lays them.
The pair of amorous toads were released into one of the ponds, where they swam off together, still in amplexus. Their offspring will be born into the pond as tadpoles, along with those of the chorus frogs, the red-legged frogs, and hopefully not too many bullfrogs. Incidentally, herpetologists use the term ‘tadpole’ to refer only to the larvae of frogs and toads; Robert calls the larvae of his study salamanders just ‘larvae’.
We ventured over to the Fort Ord Natural Reserve (FONR), where we ate our lunch in a clearing surrounded by coast live oaks and coastal scrub. FONR is one of five natural reserves managed by UC Santa Cruz as an outdoor classroom and teaching lab. School groups ranging from elementary school to university levels visit FONR to learn about the natural environment, often for the very first time.
FONR sits on an ancient sand dune, and all of the vegetation has had to adapt to difficult growing conditions. The soil is almost entirely sand and doesn’t hold water at all. The wind picks up just about every afternoon and blows in salt from the ocean; these winds can be quite fierce even without the salt. The sand itself gets blown around, making an unstable substrate. As a result, plants that would otherwise grow tall are stunted here. Take, for example, the coast live oak (Quercus agrifolia). In places that are more sheltered from the wind, they are tall and majestic, even as they continue their meandering growth form. At FONR they are much shorter and more closely resemble the other scrub plants than actual trees.
After lunch we heard from Dani, a UCSC undergraduate student studying horned lizards (Phrynosoma sp.). The lizards are very well adapted to this environment. They live in sand, and have flattened bodies so they can hide on top of the sand and become practically invisible. Like the tiger salamanders the horned lizards are underground now. They should emerge in the next couple of months. This is one that we saw last May, when Joe invited last year’s class to visit the Reserve on a Saturday, after our planned field trip was cancelled due to rain.
In early March the plants were starting to bloom. One of the earliest bloomers is this delightful plant called ‘footsteps of spring’; its real name is Sanicula arctopoides. They look like small blotches of yellow spray paint against the ground. And when you see several of them scattered on the trail, you really understand their common name.
There were, of course, no horned lizards to be seen. We did, however, hike the reserve, and Joe showed us some of the endemic and/or endangered plants that live there. That’s Joe, in the front of the group here:
Fort Ord Natural Reserve 2019-03-08
Our last stop at the end of the field trip was at a location where the Army used to work on fire suppression. They did this by dumping various flammable items and fuels on the ground, lighting them on fire, and putting them out. This activity resulted in groundwater and soil contamination, which Army contractors have been working to clean up for 20 years now. Currently the site is where Robert is raising his tiger salamander larvae in raised ponds; he will eventually release the larvae into the artificial pools that we saw earlier in the day.
Each of those ponds is filled with natural rain water and contains a small screened tub into which Robert placed 10 salamander eggs. The larvae, after they hatch and have used up all of their yolk reserves, feed on whatever zooplankton have sprung up in the ponds–a quick glance showed that copepods, ostracods, and insect larvae had already taken up residence. The idea is that the salamander larvae will escape from their tubs into the pool at large, which will give them lots of room to grow up.
In a very real sense, this field trip ended where it started. Things don’t always work out this nicely, and my Type A personality is pleased at both the symmetry and the closure. Because these field trips are necessarily snapshots of what is happening at a particular moment in a particular place, it can sometimes be difficult to connect them to the real world. This week, though, I feel that my students got the whole story, or at least the entire outline of it. This visit to FONM and FONR may very well be my favorite field trip of the class, because I learned so much about things that are new to me. Thank you, Joe, for arranging such an amazing day for us!
Combine the words “gold” and “California” and you automatically come up with the Gold Rush, don’t you? After all, California is the Golden State. And while that nickname may be to honor the golden hills of summer or the poppies that are the state flower, it may also be a tribute to the discovery of gold in 1848. For better or worse, the Gold Rush initiated rapid development of this area, and California eventually became the 31st state in 1850.
For me, and I suspect for many people, gold is one of the quintessential colors of autumn. Yet here we are in the middle of winter heading towards spring, and I saw a lot of gold in the forest the other day. I had taken my Ecology students to Rancho del Oso for the first field trip of the semester and set them loose to saunter through the woods and practice noticing (and recording) patterns in nature. Incidentally, I have adopted the word ‘saunter’ as a replacement for ‘hike’ for most of my own outdoor adventures. I have always been a slow hiker, and felt that in order to keep up with other people I had to miss seeing what was going on around me. Not to mention the fact that I’m always stopping to take pictures or examine some weird thing on the ground, or in the trees, or wherever. By giving myself permission to saunter along at the pace at which nature occurs, I have time to slow down and observe more carefully, and come away with a much better understanding of the world I’ve passed through. It certainly doesn’t work for everybody, but I’ve learned that the journey is as important as the final destination, and that has made hiking sauntering much more enjoyable for me.
So, back to the gold. One of the very first thing I noticed when we hit the trail was this brilliant yellow-orange slime mold growing on twigs on the forest floor. This area is a mixed forest of hardwoods (mostly oaks) and various pines. I can’t be certain what these sticks hosting the slime mold are, but they may be some kind of pine.
Slime molds are very strange organisms that don’t fit into any of the major eukaryotic kingdoms of life (Animalia, Plantae, or Fungi). The current taxonomic position of slime molds is up for debate and far from settled, so I won’t go into it here. Like fungi, slime molds feed on dead and decaying plant matter and are part of the decomposer niche of organisms. Also like fungi, most of a slime mold’s life is microscopic. In the case of fungi most of the body, called a mycelium, is a network of extremely thin threads called hyphae. The mycelium for most fungi is underground and thus invisible to the casual observer. What we call a mushroom is only the reproductive fruiting body, which pushes to the surface so that spores can be released into the air.
For most of the time, or at least as long as food is plentiful, a slime mold exists as single amoeba-like or flagellated cells that feed on bacteria. These cells are haploid, containing only one set of chromosomes. Sexual reproduction (labelled SYNGAMY in the figure below) occurs when an amoeba-like cell encounters a compatible flagellated cell. I would also be willing to bet that the amoeboid and flagellated cells are triggered to find each other and initiate syngamy when food is scarce, as is the case with many animals.
The result of syngamy in a slime mold is a zygote which develops into a macroscopic stage called the plasmodium. The plasmodium undergoes nuclear division multiple times but cytokinesis doesn’t occur, resulting in a large cell bounded by a single plasma membrane and containing many nuclei. In animal tissues we describe this condition as syncytial; I don’t know if the same word is used by slime mold specialists, but the concept applies.
One of the things that makes slime molds truly bizarre is their method of locomotion. Using time-lapse videography, you can actually see how the contents of the cell swash back and forth in a process called cytoplasmic streaming. The net result of all this cytoplasmic streaming is the physical movement of the plasmodium into new territory. It’s a process much easier to understand if you can see it, so here’s a video from KQED’s Deep Look series:
As with many fungi, slime molds are difficult to identify if you don’t see the fruiting body. The slime mold that we encountered the other day was an immature plasmodium that hadn’t yet produced fruiting bodies. The experts who took a look at my observation on iNaturalist agreed that it is likely Leocarpus fragilis, based on location and time of year, but they cannot be certain.
Continuing with our theme of gold, we saw several small blotches of golden jelly growing on tree trunks. These were the Tremella fungi. There are two species of golden Tremella in our region, T. mesenterica and T. aurantia. It seems that differentiation between the species depends on examination of microscopic structures, so I am unable to tell which species this little blob is. However, I will point out that the species epithet aurantia means ‘gold’, so I really hope that’s the name for this blob.
Saving the best for last! Moving away from the creek and into the more enclosed forest we entered the realm of everybody’s favorite terrestrial pulmonate gastropod, the banana slug. They were out in full force, chowing down on mushrooms and sliming up the foliage. One of my students picked up a banana slug and let it crawl on her hand for a while, but to my knowledge nobody licked one. All of the banana slugs that I saw were bright yellow with no brown or gray blotches, so I conclude that they were either Ariolimax californicus (the so-called Peninsula banana slug) or A. dolichophallus (the Santa Cruz banana slug, also the school mascot for UC Santa Cruz).
But this is where things get interesting. According to their mitochondrial DNA these two species, A. californicus and A. dolichophallus, do not have overlapping ranges. And the dividing line between them is Rancho del Oso, with A. californicus occurring to the north and A. dolichophallus occurring to the south. So, if Rancho del Oso is the magic line defining the ranges of these two species, what species are the slugs at Rancho del Oso? I think that answering this question will require a much finer scale study. For now, I’m just going to call them Ariolimax sp., because that seems to be the safest option until things get sorted out.
I’ve written about banana slugs before, but I’ve never had a chance to photograph them doing the actual nasty. Luckily for me and the students, banana slugs have no shame. I think the entire class got to get a close look and photos of this copulating pair:
This perfect yin-yang symbol is the result of how banana slugs align themselves during copulation. Each hermaphroditic slug has a genital open behind the head on the right side of the body. There’s a lot of kinky stuff that happens during banana slug sex, including the chewing off of one partner’s penis, but suffice to say that one animal’s penis is inserted into the vagina of the other and, well, we don’t know how quickly sperm is transferred, but the animals remain locked together for several hours. Yes, HOURS. Ahem. The penis chewing thing doesn’t happen every time slugs mate, and biologists are still trying to figure out the function for this unusual behavior.
We have another several weeks (hopefully!) of rainy weather, so there will be lots of time to explore the world of fungi, slime molds, and banana slugs. The combination of rain and lengthening days creates great conditions to revel in the gold of a California winter in the forest.
The spring semester started this week, which means that every Friday I’ll be taking my Ecology students on field trips. Yesterday’s field trip, the first of the class, was to Rancho del Oso and Waddell Beach. Every year I’ve taken the students to these sites to visit two different habitats: forest and beach. And all we have to do to get from one to the other is cross the highway. The beauty of this particular field trip is that it is almost entirely unstructured. My goal is to give the students a chance to spend time outdoors and slow down enough to really observe what’s going on around them. They get to crack open their brand new notebooks and work on their first entries, which can be a little intimidating for them. One suggestion I made was to find a spot to sit quietly, close their eyes, and observe the world using their other senses. Since we humans are such visual creatures, people are always surprised to discover how much they can perceive with their eyes closed.
Getting to do yesterday’s field trip at all wasn’t something to be taken for granted. There are some storm systems working their way through the area. They’re nothing like the polar vortex that has been subjecting the midwest and now the east coast to well-below-freezing temperatures, but are projected to dump a lot of rain and blow like crazy. I’d been keeping an eye on the weather forecast all week, hoping that the rain on Friday would at least hold off until the afternoon so we could do the forest part of our field trip. I figured that if we got to any of the beach stuff after lunch that would be gravy.
Here we are, in the midst of winter, and already there are signs of spring. The willows are starting to leaf out and there was a lot of poison oak putting out leaves, all shiny and dangerous. Fortunately the poison oak is easy to recognize–and avoid–when it has leaves, and hopefully nobody who is allergic was exposed to it.
Of course, one of the best things about the forest in winter is the mycoflora. Rancho del Oso is a good place to see mushrooms and slime molds, and yesterday I saw things that I’d never seen before. Now, I’m not a mycologist by any stretch of the imagination. But I did my best, with the help of Mushrooms of the Redwood Coast and iNaturalist, to identify the ones I saw and managed to take decent photos of. And some remain unidentified. I simply don’t know enough to make more than a very rough guess, which isn’t at all likely to be correct.
When people think of the genus Amanita they think of things like the death cap mushroom (A. phalloides) or A. muscaria, with its iconic white-spotted red cap. But Amanita is a large genus, with many species categorized into several sections. Not all of the Amanita mushrooms are poisonous, and some are edible if prepared properly. This one is a rather nondescript brown, but based on photos in MotRC, Amanita fruiting bodies come in various shades of white, gray, yellow, brown, and russet. It’s going to take me a lot of time and practice to begin getting these mushrooms straight!
I’ve always been drawn to the various shelf or bracket fungi because their morphology is so un-mushroomlike. Most of the bracket fungi we have here are polypores, meaning that the fruiting body releases spores through holes on the bottom surface rather than the more familiar gills you see on mushrooms. The very common and variable turkey tail (Trametes versicolor) grows on many host species is a polypore. Its congener, T. betulina, however, has gills. The rather paradoxical common name of T. betulina is gilled polypore, which of course doesn’t really make sense.
Of course, I forgot to look at the bottom surface of this bracket fungus, so I don’t know which species of Trametes it is. Naturalist fail!
This bizarre mushroom, which looks like a miniature bok choy that is black instead of green, is an elfin saddle in the genus Helvella.
According to MotRC there are two species of Helvella that co-occur in this area and can be difficult to distinguish without genetic analysis. Helvella vespertina (western black elfin saddle) is associated with coniferous trees and fruits in autumn and winter. Helvella dryophila (oak-loving elfin saddle) is usually found in with oaks and produces fruiting bodies in winter and spring. Because we saw this mushroom in a mixed forest in the middle of winter, I’m going to play it safe and stick with Helvella sp.
These red-capped mushrooms are a species of Russula, I think. It looks like they’ve been munched on, perhaps by banana slugs. More on that in the next post!
There are some very bizarre fungi out there! Some of them have fantastic fruiting bodies, and some are much more blobby. The jelly fungi are very aptly named, and are the blobbiest. We saw lots of little bright orange blobs growing on hardwoods. These are called witch’s butter, known to mycologists as Tremella aurantia:
Despite the common name, T. aurantia is edible but apparently not appealing. So eating it won’t make you sick, but you may still wish you hadn’t eaten it. When it comes to mushrooms, that’s definitely not the worst possible outcome. Given my own lack of expertise with mushrooms I’m one of the last people to tell you which ones to eat. But I do know enough not to eat anything that I find in the field. Some day I hope to go mushroom foraging with someone who really knows what he or she is doing, and whose judgment I trust. Until then, I’ll continue to enjoy mushrooms where they grow and not concern myself with issues of edibility. The mushrooms certainly do deserve to be appreciated for their appearance and the ecological relationships they form with the plants and animals of the forest.
This semester I am teaching a lab for a General Biology course for non-majors. I polled my students on the first day of lab, and their academic plans are quite varied: several want to major in psychology (always a popular major), some want to go into business, a few said they hope to go into politics or public policy, and some haven’t yet selected a field of study. I think only one or two are even considering a STEM field. Which is all just to say that I have a group of students whose academic goals don’t have much in common except to study something other than science. Several of them are the first in their families to go to college, which is very exciting for them and for me.
Most of the activities we do in this class are lab studies. Last week, for example, the students extracted DNA from a strawberry (100% success rate for my class, thank you very much) and then used puzzles and 3-dimensional models to understand the structure of DNA. We do have a couple of field trips scheduled, though, which are the days that students really look forward to. Outside the classroom is where most of the fun stuff happens.
Today I took my class to the beach! We were there to do some monitoring for LiMPETS (Long term Monitoring Program and Experiential Training for Students). For the past few years I’ve taken my Ecology students out to the intertidal to do the rocky intertidal monitoring. The General Bio students don’t have the background needed for the intertidal monitoring and I don’t have the classroom time to train them, so we take them to do sand crab monitoring instead. This is a simpler activity for the students, although the clean-up on my end is a lot more intensive even though I get them to help me.
Emerita analoga is a small anomuran crab, more closely related to hermit and porcelain crabs than to the more typical brachyuran crabs such as kelp and rock crabs. It lives in the swash zone on sandy beaches and migrates up and down the beach with the tide. Its ovoid body is perfectly shaped to burrow into the sand, which this crab does with much alacrity. The crabs use their big thoracic legs to push sand forward and burrow backwards into the sand until they are entirely covered. They feed on outgoing waves, sticking out their long second antennae (which can be almost as long as the entire body) and swivel them around to capture suspended particles.
Emerita analoga feeding in an aquarium
We went out to Seacliff State Beach to count, measure, and sex sand crabs. The protocol is to lay out a 50 m transect along the beach, roughly parallel to the shore where the sand remains wet but isn’t constantly covered by waves. Students draw random numbers to determine their position along the horizontal transect and venture out into the ocean, measuring the distance between the transect and the point where they are getting wet to the knees. Then they divide that distance by 9 to yield a total of 10 evenly spaced sampling points along a line running perpendicular to the transect.
The corer is a PVC tube with a handle. It is submerged into the sand to a specified depth and collects a plug of sand that is dumped into a mesh bag. Sand is rinsed out of the bag and the crabs remain behind. Students then have to measure and sex each of the crabs.
Each crab is classified as either a recruit (carapace length ≤9 mm) or a juvenile/adult (carapace length >9 mm). Students get to use calipers to measure carapace length, which they enjoy. Adult crabs are sexed, and females are examined for the presence of eggs.
A sand crab’s sex is determined by the presence or absence of pleopods, abdominal appendages that females use to hold onto eggs. If a female is gravid, the eggs are visible as either bright orange or dull tannish masses tucked underneath the telson (see below):
The pointed structure in the photo above is the telson. You can see the tan eggs beneath the telson. They look like they would fall off, but they adhere together in a sticky mass until they are ready to be released. Adult females have pleopods whether or not they are gravid, making it easy to sex the crabs even when they are not reproductive.
Most of the larger crabs today were gravid females and could be sexed with a quick glance at the ventral surface. Sexing the smaller individuals requires a lot more effort. The crab’s telson has to be gently pulled back to expose the abdomen, which isn’t easy because the crab doesn’t like having its parts messed with. In fact, one of the ways to determine whether or not a crab playing dead is really dead is to pry up its telson–a dead crab will let you without making a fuss, while a live one will start thrashing about.
It was a good day to spend time at the beach. The weather got better as we worked and the water wasn’t very cold. The students had a good time splashing around in the waves, and they all fell in love with the crabs. There were a few sad moments when crabs got chopped in half by the edge of the corer, but the vast majority were released back to the ocean unharmed. From a teaching perspective, I was happy to give the students an opportunity to do some outdoor learning. After all, the world is our biggest and best classroom. Most students learn best when they get to actually ‘do’ science, and even though most of this group will not go on to complete a science major, they hopefully have a better appreciation of what it is like to collect real data as citizen scientists.
How does a group of people go about trying to save a federally endangered species? The answer, of course, depends on the species. However, you can bet your bottom dollar that it takes a tremendous effort over many years by many dedicated and talented people, all of whom know that in the end their work may not succeed. Ultimately it is society who decides whether or not such efforts, costly in both person hours and dollars, are worthwhile. After all, we are the people who vote elect the legislators to decide how our tax monies are spent. Not only that, but which of the many endangered species should we try to save? Can we save them all? Should we try to anyway? If not, then how do we decide which species are worth the effort? And what should we do about the species that are deemed unworthy?
Today I took my Ecology students to locations on Scott Creek and Big Creek in northern Santa Cruz County, where biologists are working on saving the coho salmon, Onchorhynchus kisutch. Our guide for the day was Erick, a fisheries biologist with the National Marine Fisheries Service (NMFS), a division of the National Oceanographic and Atmospheric Administration (NOAA). Erick’s job is to maintain the genetic diversity of this population, which occupies the southernmost part of the coho’s range in North America. The coho is a federally endangered species in California, and this southern population represents the species’ best chance for surviving and adapting to the ocean and river conditions that are predicted due to climate change.
Our first stop was at the weir and fish trap on Scott Creek. There are actually two fish traps in this location: one to catch adult salmon swimming upstream and one to catch smolts migrating downstream (more about that in a bit). Adult salmon returning to spawn come into the trap and end up in the box to Erick’s right. Every day during the spawning season at least two people come down to the weir to count, measure, sex, and weigh each fish in the trap. Then the salmon are trucked up to the hatchery, where they will be used for spawning under controlled conditions. The stretch of creek behind Erick is located between the fish traps; there are no salmon in it because the adults are all captured by the large trap, and the outgoing smolts are caught in the upstream trap.
The smolts are netted out, put into buckets, and carried downstream past the adult fish trap. From there they migrate out to the ocean, and if all goes well they will spend the next two years feeding and growing before they return to the creek as adults.
Adult coho salmon caught in the trap are trucked up to the hatchery, which is located on Big Creek. There has been a hatchery on this site since the early 1940s. The current installation is operated by the Monterey Salmon and Trout Project, with permission of the landowners and from the state. Erick and his fellow fisheries biologists are charged with maintaining the genetic diversity within this small population of fish. They do so by keeping track of who mates with whom and making sure that closely related individuals do not mate. Each female salmon’s eggs are divided into separate batches to be fertilized with as many as four males. Each male’s sperm can be used to fertilize up to four females’ eggs.
Fertilized eggs are incubated in a chamber set at 11°C and 100% humidity; in other words, they are not incubated in water. Once they hatch they are transferred to trays of water, where they remain until they have used up their entire yolk sac and need to be fed. Each of these trays contains one family of fry; in other words, all of the babies from one female-male mating.
From these trays the fishlets move into indoor tanks and then outdoor tanks. They are fed, and this is when they develop one of the bad habits of all hatchery fish: they get used to food coming from above and drifting down. In the wild, a juvenile salmon in a stream feeds on aquatic insects, small crustaceans, and the like. Many of their favored prey items are benthic, but they will also feed on insects at the surface. To do so, they have to spend time going up and down in the water column, when they are at risk of being eaten themselves. Hatchery-reared juveniles don’t have predators to deal with and have learned that food lands on the surface of the water. They don’t understand the need to remain hidden, and many of them get picked off by birds and other fish.
As a safeguard against an extremely poor return of spawning adults, each year some portion of the juveniles are kept at the hatchery and grown to adulthood on-site. This means that even if very few fish return to the river, or if there aren’t enough females, the captive breeders can be used to make up the difference. This year, the 2017-2018 spawning season has so far been successful. As a result there were adult salmon that, for whatever reason, were not used as breeders. Today just happened to be the day that they would be returned to the creeks, where they may go ahead and spawn, and we got to watch part of it.
Returning to the story of the outmigrating juveniles, one of their biggest challenges is smoltification (my new favorite word), the process of altering their physiology in response to increasing salinity as they move towards the ocean. This is a unidirectional change in physiology for salmon; once they have fully acclimated to life in the ocean they cannot re-acclimate to the freshwater stream where they were born. Smoltification takes place over a few to several days. The hatchery has several year-old fish ready to smoltify (I think that’s the verb form of the word) and will be releasing them in several batches at approximately two-week intervals starting later in March. The outgoing fish are tagged so that when they return in two years the hatchery staff will be able to determine which batch they came from, helping them understand what release conditions resulted in the greatest survival and return of adults. Kinda cool, isn’t it?
The bad news is that as of right now any baby fish released into the creek won’t be able to get to the ocean. We haven’t had enough rain recently to break through the sand bar that develops on the beach where Scott Creek runs into the sea.
It will take some decent rainfall to generate enough runoff to breach the sand bar. A good strong spring tide series would help, if it coincides with a big runoff event. We are supposed to get some rain this weekend and into early next week. I hope it’s enough to open the door to the ocean for the smolts. In the meantime, they will hang out on the other side of the highway in the marsh.
They’ll have to wait until the ocean becomes available to them, and in the meantime will be vulnerable to predators, especially piscivorous birds. Hopefully the rains in the near forecast will be heavy enough to open up the sand bar and the smolts will be able to continue their journey out to sea. Good luck, little guys!
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.
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.
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.
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.
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?
