Tag: field trip

There’s gold in the forest

Posted on by Allison J. Gong

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 mold
Slime mold, possibly Leocarpus fragilis, at Rancho del Oso
2019-02-01
© Allison J. Gong

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.

Life cycle of a slime mold
© Pearson Education, Inc.

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.

One of the golden jelly fungi (Tremella sp.) at Rancho del Oso
2019-02-01
© Allison J. Gong

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).

Banana slug (Ariolimax sp.) at Rancho del Oso
2019-02-01
© Allison J. Gong

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:

Copulating banana slugs (Ariolimax sp.) at Rancho del Oso
2019-02-01
© Allison J. Gong

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.

Winter wildlife

Posted on by Allison J. Gong

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.

Willows
Willows (Salix sp.) starting to leaf out at Rancho del Oso
2019-02-01
© Allison J. Gong

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.

Amanita sp. at Rancho del Oso 2019-02-01
© Allison J. Gong

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!

Bracket fungus (Trametes sp.) at Rancho del Oso
2019-02-01
© Allison J. Gong
Helvella sp. at Rancho del Oso
2019-02-01
© Allison J. Gong

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!

Russula sp. at Rancho del Oso
2019-02-01
© Allison J. Gong

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:

Witch’s butter (Tremella aurantia) at Rancho del Oso
2019-02-01
© Allison J. Gong

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.



Playing in the sand, for science

Posted on by Allison J. Gong

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.

Dorsal view of Emerita analoga at Franklin Point
15 June 2018
© Allison J. Gong

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.

Students collecting sand crabs at Seacliff State Beach
28 September 2018
© Allison J. Gong

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.

Rinsing the bag
28 September 2018
© Allison J. Gong
“What’s in the bag?”
28 September 2018
© Allison J. Gong

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.

Students measure a sand crab (Emerita analoga)
28 September 2018
© Allison J. Gong

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):

Ventral view of gravid female Emerita analoga
15 June 2018
© Allison J. Gong

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.

Students sexing a sand crab (Emerita analoga)
28 September 2018
© Allison J. Gong

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.

Blitzing an old military base

Posted on by Allison J. Gong

This weekend a subset of my students and I spent a day at the Fort Ord Natural Reserve (FONR) to participate in the 2018 spring Bioblitz. We were supposed to visit FONR for a class field trip in early March to do some vegetation studies, but that trip was rained out. Today’s visit was sort of a make-up for that missed lab; because it’s a Saturday I couldn’t compel the students to attend, but I offered a little extra-credit for those who did. It just so happened that Joe Miller, the field manager at FONR, had organized a Bioblitz for another group of students, and he welcomed my Ecology class as well.

Map of communities surrounding Monterey Bay
© Google Maps

Located adjacent to the city of Marina in Monterey County, FONR is one of five natural reserves administered by the campus of UC Santa Cruz. The other four are the Campus Reserve (on the main campus of UCSC), Younger Lagoon Reserve (on UCSC’s Coastal Science Campus), Año Nuevo Natural Reserve (up the coast in San Mateo County), and Landels-Hill Big Creek Reserve (along the Big Sur coast). FONR occupies some 600 acres of a former military base that was closed in 1994. The reserve opened in 1996. As with all the other UC natural reserves, FONR exists to provide students, teachers, and researchers with natural lands to be used as outdoor classrooms and laboratories. Field courses at UC Santa Cruz and CSU Monterey Bay make extensive use of FONR, and students carry out independent studies and internships there.

After all of the participants arrived at the Reserve, Joe described the activities he had planned for the day. He told us that we could wander around the Reserve on our own if we wanted, but there were several hikes we could choose to join:

  • One to where some people were finishing up the day’s bird banding activities
  • One to collect samples of environmental DNA
  • One to ID various tracks in the sand
  • One to the different habitats and vegetation types
  • One to check out some pitfall traps for small rodents and reptiles

Because my knowledge of the local flora is sorely lacking, I went on the plant hike with Joe. Many of the spring wildflowers had either finished or were finishing up their yearly bloom. The poison oak (Toxicodendron diversilobum) is looking amazing this year; I think it has been able to take advantage of two consecutive wet seasons with a decent amount of rain. There were many poison oak plantlets scattered around all over the place, and the established bushes are lush and green. There is no way I didn’t come into contact with the stuff at least once on this hike, so today is going to be the true test of whether or not I am allergic to it.

One of many poison oak (Toxicodendron diversilobum) plants at Fort Ord Natural Reserve
12 May 2018
© Allison J. Gong

Much of the terrain at FONR is a maritime chaparral. The soil is extremely sandy (Pleistocene sand dunes, Joe says) with a poor nutrient load and water content. It’s not a desert, because we do get a fair amount of precipitation along the Monterey Bay, but the plants have adapted to thrive with low soil moisture levels. It’s also often very windy, and there are no trees. Even the coast live oaks (Quercus agrifolia), which can be magnificently massive and meandering, are stunted here. Much of the foliage is low-growing perennial shrubs or annual plants.

Coast live oak (Quercus agrifolia) growing above coyote bush (Baccharis pilularis) at Fort Ord Natural Reserve
12 May 2018
© Allison J. Gong

Joe led us through the habitats of the Reserve, mostly on trails but also along narrow-to-nonexistent tracks that we called Poison Oak Lane, Rattlesnake Drive, and Tick Alley. And yes, we did see a rattlesnake! My husband spotted it, right about where he was going to put his foot. It wasn’t a big snake, maybe half a meter long, and was sunning itself in a narrow opening between manzanita bushes. I didn’t stop to take a picture because there wasn’t a good space to do so, and I wanted to let other hikers pass the snake quickly. The snake didn’t seem to react to us, but it’s always a good idea to leave them alone.

Just beyond where we saw the rattler, Joe had found a pair of southern alligator lizards (Elgaria multicarinata) mating. When Joe picked them up the male had grabbed the female with a bite behind her head; he does this to keep her from running away, and it also shows his strength and suitability as a father for the female’s offspring. The lizards didn’t like being interrupted in copulo, so to speak, and the male released the female and escaped back to the ground, leaving his lady love behind in Joe’s hand. Hopefully they were able to find each other again once they were both let go.

Joe Miller (left) holding a female southern alligator lizard (Elgaria multicarinata) in his left hand
12 May 2018
© Allison J. Gong

To me, the picture above exemplifies what a Bioblitz is all about. We have two people examining a natural phenomenon, and one of them is taking a picture that he will presumably upload to iNaturalist. People learn a lot when they participate in a Bioblitz–they usually see things they’ve never paid attention to before, and when their observations are ID’d or corroborated by the community of iNat experts, they get to put a name to the thing they saw. True, it’s a better learning experience to sit down with a specimen, hand lens, and book to figure out what an organism is, but most people don’t have either the inclination or the luxury of time and the necessary books. And while I’d rather have people look at the real thing with their eyes instead of their phones, getting people to go outdoors and pay any attention at all to their surroundings is a minor victory. I find Bioblitzes to be a little unsettling sometimes. My preferred method for observation is to examine fewer things in greater depth; this is what my graduate advisor Todd Newberry referred to as “varsity” observations. I don’t think a Bioblitz has any place in varsity studies, because of its very raison d’être–to record as many observations as possible–means to some degree that instead of taking a deep look you have to glance-and-go. Still, it does have its place in natural history, and I value it as a way to get more people involved in science.

I was on the plant hike, so many of the organisms I photographed and uploaded to iNat are new to me. Some are California endemics and all have adapted to survive in the difficult conditions of a maritime chaparral.

Eriastrum sp., a plant with delicate blue-purple flowers, at Fort Ord Natural Reserve
12 May 2018
© Allison J. Gong

And I did see one of the California native thistles. Invasive thistles are such a problem that the knee-jerk response is to stomp on them or yank them out of the ground. This one, for which I’m still waiting on an ID confirmation, is silvery and sort of looks like cobwebs. Joe said that its blossom is a bright pink.

A California native thistle, possibly Cirsium occidentale, at Fort Ord Natural Reserve
12 May 2018
© Allison J. Gong

And one of my newish old favorite wildflowers, Castilleja exserta, was there. The purple owl’s clover occurs throughout California; in 2017 I saw a lot of it on my wildflower excursion to the southern part of the state. It varies in color from purple to pink to white and thus has multiple common names.

Castilleja exserta, the purple owl’s clover, at Fort Ord Natural Reserve
12 May 2018
© Allison J. Gong

We also saw a lot of the peak rushrose, Helianthemum scoparium. It is a California native species that does well in dry, sandy areas, such as throughout most of Fort Ord.

Peak rushrose (Helianthemum scoparium) at Fort Ord Natural Reserve
12 May 2018
© Allison J. Gong

While I was leaning down to photograph this plant, one of the Reserve volunteers pointed out a much paler version nearby. He told me that most of the time the peak rushrose has brilliant yellow flowers, but there are always a few that have this much more delicate color.

Pale form of peak rushrose (Helianthemum scoparium) at Fort Ord Natural Reserve
12 May 2018
© Allison J. Gong

And speaking of yellow, I discovered another new-to-me organism! What at first glance looked like a blotch of spray paint on a tree trunk turned out to be something much more interesting–a gold dust lichen in the genus Chrysothrix.

Gold dust lichen (Chrysothrix sp.) at Fort Ord Natural Reserve
12 May 2018
© Allison J. Gong

The lichen book1 that I have describes two species of Chrysothrix, both of which can be found in coastal regions of California. The species have some overlap in habitat, with C. granulosa usually living on bark and occasionally on wood or rock, while C. xanthina can regularly be found on bark, wood, and rock. Nor is color by itself an entirely useful characteristic: C. granulosa is described as brilliant yellow, and C. xanthina can be brilliant yellow, yellow-green, or yellow-orange. There are certain tests that would be able to distinguish between the species, but field ID when the lichen is ‘brilliant yellow’ remains problematic. So while I’d guess that this specimen is Chrysothrix granulosa (based on a combination of color, location, habitat, and good old-fashioned gut feeling) I can’t be at all certain.

The discussion of lichens brings us around to the animals. Did you know that fungi are more closely related to animals than they are to plants? Well they are, despite being included in more botany than zoology courses. And of course we did see animals on our plant hike. Hawks and turkey vultures soared overhead, song birds and hummingbirds flitted among the trees and shrubs, alligator lizards mated, and there was that one rattlesnake, which even the people on the herps walk didn’t get to see. As we hiked through the various plant communities in the Reserve, Joe occasionally called out “If you see a horned lizard, catch it!” A woman in our group, Yvonne, managed to do so, despite being loaded down with a backpack and a camera. She pounced on it and held it up for us to photograph.

Horned lizard (Phyronosoma sp.) at Fort Ord Natural Reserve
12 May 2018
© Allison J. Gong
Horned lizard (Phrynosoma sp.) at Fort Ord Natural Reserve
12 May 2018
© Allison J. Gong

Cute little thing, isn’t it?

The last critter we saw as we were walking back to the gate after lunch was a juvenile gopher snake (Pituophis catenifer). By the time I got there the snake was resting in the road. It was a very pretty snake. I wanted to take it home and release it into my yard, where there are enough gophers to feed an entire family of snakes, but alas, collecting is not allowed at the Reserve. I do wish that a gopher snake would move into my yard, though.

It is now about 24 hours since we got home. We did our tick checks and didn’t find anything, thank goodness, then showered and scrubbed. There’s no doubt that we were both exposed to poison oak; it is impossible NOT to be, this time of year. This is the real test for whether or not I am allergic to it. I haven’t been so far, but there’s a first time for everything and I will never say that I will never get it. My husband, who gets poison oak very easily and very badly, says it could take up to two days to be sure. I’m not itchy today. Tomorrow may be a different story, though.

1Sharnoff, S. 2014. A Field Guide to California Lichens, Yale University Press

Saving a species

Posted on by Allison J. Gong

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?

Erick (green jacket) gives my students an introduction to the weir on Scott Creek
9 March 2018
© Allison J. Gong

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.

Erick explaining how the fish trap works
9 March 2018
© Allison J. Gong

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.

Upstream end of the smolt trap on Scott Creek
9 March 2018
© Allison J. Gong

At this point the entire creek passes through those screened panels, and the fish are directed into this box:

Smolt trap on Scott Creek
9 March 2018
© Allison J. Gong

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.

Erick shows us trays containing salmon fry
9 March 2018
© Allison J. Gong

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.

Scott Creek Beach
9 March 2018
© Allison J. Gong

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.

Scott Creek just upstream of where it crosses under Highway 1
9 March 2018
© Allison J. Gong

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!

Students begin observing succession

Posted on by Allison J. Gong

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.

Students examining their study plot
9 February 2018
© Allison J. Gong
Sometimes a little ballast is required!
9 February 2018
© Allison J. Gong

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:

9 February 2018
© Allison J. Gong

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.

White plumose anemones (Metridium senile) at the Santa Cruz harbor
9 February 2018
© Allison J. Gong
Oral view of white plumose anemones (Metridium senile) at the Santa Cruz harbor
9 February 2018
© Allison J. Gong

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 non-native hydroid, Ectopleura crocea, at the Santa Cruz harbor
9 February 2018
© Allison J. Gong
Caprellid amphipods at the Santa Cruz harbor
9 February 2018
© Allison J. Gong

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!

Feather duster worm (Eudistylia polymorpha) at the Santa Cruz harbor
9 February 2018
© Allison J. Gong

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?

9 February 2018
© Allison J. Gong

The oldest and most powerful skill of all

Posted on by Allison J. Gong

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

OLYMPUS DIGITAL CAMERA

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

Gettin’ down and dirty

Posted on by Allison J. Gong

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

Let there be . . . fish!

Posted on by Allison J. Gong

Today my students and I visited the Monterey Bay Salmon and Trout Project hatchery, to learn about local efforts to save the federally endangered coho salmon (Oncorhynchus kisutch). The coho is one of five species of Pacific salmon found on the coast of North America, the other four being the Chinook (O. tshawytscha), the chum (O. keta), the sockeye (O. nerka), and the pink (O. gorbuscha). The coho’s range extends in the North Pacific from northern Japan up along Russia, across the Aleutians, and down the coast of North America to the northern bit of Monterey Bay. In our area the coho return to their natal streams (Scott Creek, Big Creek, and occasionally the San Lorenzo River) during the winter rains in January and February.

The local population of coho make up an evolutionarily significant unit (ESU). This means that they are locally adapted to the extent that they are biologically and genetically distinct from other populations. For example, coho from Alaska, where they are much more common, cannot be successfully transplanted into our watershed because they are genetically programmed to spawn in the fall, the time of year when our streams are dry or disconnected from the ocean due to sand bars. So these fish aren’t just any old salmon. They have evolved to live in this particular watershed and as such are irreplaceable.

Our first stop of the morning was to the fish trap on Scott Creek. The weir, the structure that extends across the river in the photo below, traps fish that are swimming upstream. Once on the upstream side of the weir, the fish are directed into the cage, from which they can be removed so that fisheries biologists can collect life history data–species, sex, weight, length–before they are released to continue their journey upstream (if they are steelhead) or transported to the hatchery to be spawned (if they are coho).

Students visiting the fish trap on Scott Creek. 19 February 2016 © Allison J. Gong
Students visiting the fish trap on Scott Creek.
19 February 2016
© Allison J. Gong

No fish were in the trap when we got there this morning but our host, a NMFS biologist named Erick, told me that eight coho had been caught yesterday. We did see a pair of steelhead swimming in the water upstream of the weir. Anytime I see a fish out of water, I forget how difficult it is to find them when they’re in their natural habitat. The spots on a steelhead’s back blend in perfectly with the ripples of the water and the gravel of the stream bed.

Pair of steelhead in Scott Creek. 19 February 2016 © Allison J. Gong
Pair of steelhead in Scott Creek.
19 February 2016
© Allison J. Gong

Do you see two faintly reddish blurs in the photo above? Those are the fish. They are facing upstream, to the right. The larger fish on the top is the female.

After the visit to the fish trap on Scott creek we drove up to the hatchery, which is located along Big Creek. The hatchery’s day-to-day operations are run by a couple of people from MBSTP. During the busy seasons staff and interns from the NMFS lab in Santa Cruz work up there, too, so the little hatchery building gets quite crowded. We were fortunate to get to see pretty much all the steps involved in trying to return an endangered species from the brink of extinction.

Male salmon, called bucks, are held in pens outdoors. They can contribute more than one sperm donation in a season, just as in the wild a male can fertilize the eggs of more than one female. A buck is taken from the pen, sedated, and then is milted for his sperm. The milt is collected into a glass test-tube and kept dry; once the sperm make contact with fresh water they become activated, and there is a 30-second window during which they can fertilize eggs. Sperm can also be damaged by exposure to UV radiation, so the test tubes are always held in a closed hand. Back inside the hatchery building Erick takes a look at the sperm under a microscope to make sure they can swim properly.

Female salmon are called hens. Before eggs are taken the hens are anaesthetized and examined by palpation and ultrasound to confirm that their eggs are mature. A sample of ovarian fluid is taken and sent off to be tested for disease. When a hen passes the ripeness test she is sliced open to release her eggs into four metal basins.

Collecting a sample of ovarian fluid from a ripe coho hen. 19 February 2016 © Allison J. Gong
Collecting a sample of ovarian fluid from a ripe coho hen.
19 February 2016
© Allison J. Gong

A single female’s eggs are fertilized by the sperm of four males. The fisheries biologists keep a detailed matrix of who mates with whom, so that they can avoid additional inbreeding in a population of fish that has already undergone a genetic bottleneck. Milt that has been collected from broodstock males is placed over the eggs. Fertilization occurs once fresh water is added to the basin. The egg-sperm combination is swirled (“just like panning for gold,” Erick explained) for two minutes, then the eggs are rinsed and disinfected before being placed into a 100% humidity cold incubator held at 11°C.

The eggs remain in the incubator until the embryos have developed eyes. Then they are transferred into trays through which water flows. When they’ve absorbed most of their yolk sac they get placed into large indoor trays where they will be fed until they are big enough to go into the outdoor tanks. They’ll spend about a year in the outdoor tanks and should then be ready to undergo the process of smoltification, during which their physiology undergoes the alterations necessary for the transition to marine life.

Erick explains hatchery operations, standing next to one of the outdoor pens where smolts are held. 19 February 2016 © Allison J. Gong
Erick explains hatchery operations, standing next to one of the outdoor pens where smolts are held.
19 February 2016
© Allison J. Gong

When I took last year’s class to the hatchery we didn’t get to see much activity because there were so few fish returning due to the prolonged drought and low water in the creek. This year’s El Niño, which has brought rain, has also made it possible for the fish to get into the creeks. Coho are a 3-year species, so the fish returning this year were born in 2013. These fish outmigrated as smolts into drought conditions, and fortunately for them they return during a rainy year. Their progeny will outmigrate in 2017, hopefully into a strong upwelling which will produce lots of food. And when they return in 3-4 years, I hope that there is enough rain for their creek to flow.