Over the long holiday weekend a little over a week ago we drove up the coast from Morro Bay back to Santa Cruz and stopped at Piedras Blancas to visit the elephant seals. At this time of year the breeding season is over and most of the seals have returned to sea. The adult females gave birth in late December or early January, were mated soon after, fasted for a month while they nursed a growing pup, and then abandoned said pup on the beach to resume the aquatic phase of their life. Same for the adult males, minus the birth and nursing part, of course. Oh, and most of the males didn't get to breed, either. Suffice it to say that the adult elephant seals have more or less abandoned the beach for now.
Although there were still a lot of seals on the beach, much of the real estate was unoccupied. Contrast this to the same beach in November 2015, as the seals were starting to arrive for that breeding season:
Elephant seal pups have a tough life. They are born in the dead of winter, on exposed coasts. While they are very young, one of the pups' greatest mortality risks is being run over and trampled to death by the adult males that are fighting for seniority and the right to mate with a harem of females. The moms do their best to fend off rampaging males, but the alphas are so much larger that they just run over anybody in their way. At this point in their life an elephant seal pup's main priority is to eat. They nurse almost constantly on milk that is about 50% fat. Pups are born wrinkled, with a lot of loose skin, but they soon fill out and take on the stereotypical look of fat sausages.
After four weeks of intensive nursing, a pup's life changes drastically. Its mother abandons it on the beach and returns to the sea to begin feeding again and restoring its much-depleted body stores. Remember, she has been nursing a pup and fasting for about a month and a half! Her pup is thus forcibly weaned, because she just leaves and doesn't come back. Researchers refer to these abandoned pups as weaners.
Most of the seals on the beach in late February are weaners. They will stay on the beach for another two months or so. They have to wait until they molt from their soft baby coat into a more adult coat that will better insulate them in the cold water. And after they molt they have to learn how to swim. They'll make short forays into the surf and paddle around for a bit, learning how to maneuver their bodies in the water, and then return to land to rest. In the meantime they're not feeding. This is why it is crucial for them to pack on as much weight during the four weeks that they get to nurse. Attaining that 'sausage' look is directly related to a weaner's probability of a success launch into the ocean.
But not everybody is a weaner. There are also some subadults on the beach. They, of course, swim perfectly well and can head back out to sea whenever they want. The subadults will also need to molt, but that doesn't happen until the early summer.
Don't they have the dopiest faces?
With the breeding season over, things will be quiet at the seal rookeries at Piedras Blancas and Año Nuevo. Both sites will get frantic again in December, when the adults return to land and the next reproductive cycle begins.
A week ago today, on Valentine's Day, I accompanied two students from the Natural History Club to Seacliff State Beach. Catie and Ryan, on behalf of the NHC, want to take charge of a now-empty glass display case at the visitor center and turn it into an exhibit of some sort. I became an official faculty sponsor of the NHC this semester. During the meeting as we were filling out the paperwork, I had to undergo an initiation rite: the club officers told me I had to present my 5 best bird calls. This is easy enough to do when I'm relaxed at home watching birds, but having to do it on the spot with no warning effectively drove everything I knew about birds right out of my head. Fortunately I was able to pull myself together and give them a California quail, a golden-crowned sparrow, a flicker, a chickadee, and an Anna's hummingbird. The easiest one, the acorn woodpecker ('waka-waka-waka') never even occurred to me.
A few months ago, Joseph, the head interpretive ranger at Seacliff, showed me the display case and asked if I knew of a group of students who would like to do something with it. I told him I'd ask the NHC if they'd be interested in taking on a project like this. It would be good outreach for the club and get their name and branding out into the greater community. Fortunately they jumped at the chance, and Catie and Ryan volunteered to come to Seacliff with me to meet Joseph and discuss his and their plans for the case.
Shortly after our arrival at the visitor center, a woman burst through the door and said, "We can't get out! A tree fell across the road!" And sure enough, a tree had indeed fallen across the road:
Catie, Ryan, and I figured it would be a while before the road was cleared and we could leave, so we might as well take a walk on the beach. It had been a very stormy week, with wind, heavy rain, and even snow in the area. Down at sea level we were fortunate to escape much of the really bad stuff, but the pounding rain and big swell had done some erosion damage to the shoreline and moved tons of sand down the coast, resulting in steep beaches. This is a normal phenomenon that happens during winter storms, but the extent of the sand removal was unusual even for winter.
For one thing, this structure was partially exposed:
We didn't know what this thing was. There were other parts of it poking out of the sand, too. When we got back to the visitor center Joseph told us that this object is part of the original seawall, dating to the 1920s. It was allowed to crumble into disrepair and be reclaimed by the beach, and only rarely ever sees the light of day.
We saw other interesting things on the beach, too. Dead birds are interesting, right? Of course they are!
The removal of so much sand from the beach bared a lot of rocks that had been buried underneath. Many of them were fossil rocks! Catie was pretty excited about them. And she certainly was right, because aren't these super cool?
In addition to things long dead (fossils) and recently dead (murre), we found the results of recent spawning. The Pacific herring (Clupea pallasii) is a small schooling fish with a wide geographic distribution in the North Pacific. It had been an important fishery species but in the 1990s the fishery collapsed. Since then, with managed fishing, the species has been making a slow recovery.
Herring may spawn throughout the year, but the major spawning events occur at the beginning of the calendar year, when adults venture to shallow water in protected bays and estuaries. Females prefer to lay their eggs on eelgrass and other vegetation near the shore. According to The Lost Anchovy, the herring had been spawning in various locations in San Francisco Bay throughout January 2019.
We saw several clusters of what I think are herring eggs washed up on the beach at Seacliff. Some of the clusters were still wet, but without access to my dissecting scope I couldn't determine whether they were alive. Probably not. Herring eggs are heavily preyed on by birds, so in retrospect it was surprisingly to see so many that hadn't been eaten.
All in all it was a great afternoon for Catie, Ryan, and me. We hadn't planned on getting stuck behind a fallen tree, but if you're going to get stuck behind a fallen tree there are many worse places than a state park in California. None of us had to get back to campus at any particular time so we were free to meander as the fancy struck us. While we were at it we also did a mini beach clean-up, picking up as much trash as we could. That is always a depressing endeavor, but every piece picked up is one piece removed from the environment, and that can't be a bad thing. Some leavings were never meant to wind up on the beach.
Over the holiday weekend I was in Morro Bay for a surprise 80th birthday party--not mine! The party on Friday evening was a huge success (none of the guests let the cat out of the bag), the birthday girl was completely taken by surprise, and a good time was had by all. The weather was cold and sporadically stormy the entire weekend, but the clear spells between storm squalls were gorgeous and almost a little warm.
Since it wasn't raining on Saturday morning, we went out to Morro Rock to look for peregrine falcons. There are two (I think) pairs of falcons nesting on the Rock, one of which nests on the side of the rock that is visible to people. This is nesting season, and Morro Rock has a lot of ledges that make good nesting platforms. Peregrines don't make a nest, really. They lay eggs and incubate them on ledge high up on structures--rock cliffs, buildings, bridges--that dominate the landscape. We did see one peregrine way up on the rock, identifiable through binoculars but far enough away that I couldn't get a decent photo. This is the best I could do:
So not much success with the falcons, although I could at least document that they were there. Turning away from the Rock I was able to watch a great blue heron (Ardea herodias) go after and catch and eat a juvenile rockfish! The photos tell the story, so I'll just post them.
And finally, down the hatch it goes:
And there you have it! On a day when it was too blustery for human fishers to venture out of the bay, one avian predator had a successful morning. Way to go, bird!
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.