It feels like forever since I've checked in on the cormorants at Natural Bridges. I simply haven't had time to mosey down there, take a gajillion photos, and then deal with them on the computer. But today I thought I'd give myself until lunch time to play with photos and such, before I hit the grindstone again and work on a lecture about the natural history of Big Sur.
And for the update: The Brandt's cormorants (Urile penicillatus) chicks are growing up! They're still mostly fluffy but some have a few feathers, and they're getting big now. I watched for about half an hour before realizing that the parents were feeding them; after that it was pretty easy to see when a feeding was imminent.
First, there's the behavior of the chick(s). Most of the time they are flopped like sacks of brown fluff, but when there's possible food they perk up and pay attention. It's funny how long their necks can be when stretched up! The chicks don't seem able to hold their heads up for very long yet. As we all know, however, food is a powerful motivator.
The parent also demonstrates what I think of as an about-to-regurgitate movements. It sort of reminds me of the cats' convulsions right before they hork up a hairball, only not as fast or violent. The parent cormorant stands up and sort of undulates front to back a few times, then bows low. This gets the chicks' attention and they start looking alert and expectant. The parent might go through the whole routine a few times before leaning towards the chick. The chick begins poking at the parent's bill, which seems to stimulate the actual regurgitation. Nom nom nom!
What I want to showcase this time is a series of photos showing a feeding session. The whole thing took about five seconds.
Look at those stubby little wings! These youngsters have some growing to do and have to make real feathers before they can fledge. Maybe they'll have done so by the time I finish up with school for the year.
This week was my spring break, and although I have more than enough work to catch up on, I decided that each day I would spend a few hours doing something fun before or after getting stuck in with adult responsibilities. I didn't set up formal plans, but knew I wanted to collect a plankton sample early in the week. Monday 21 March 2022 was the vernal equinox, which seemed as good a time as any to see what was going on in the plankton.
And the plankton was quite lively! I was very pleased to see a lot of diatoms in the sample. Diatoms are early season bloomers, able to take advantage of nutrient inputs due to coastal upwelling. They are usually the most abundant phytoplankters from about March through July.
All of those button-like round objects are centric diatoms in the genus Coscinodiscus. They can be large cells, getting up to 500 μm in diameter. Coscinodiscus is in some ways the quintessential centric diatom, as you will see below.
Take a look at these objects:
Clearly, one is a circle and one is a rectangle, right? Well, yes, but these two objects are the same type of thing—they are both cells of Coscinodiscus. The easiest way to understand diatom anatomy is to think of the frustule (the outer skeleton of the cell) of Coscinodiscus as being constructed like a petri dish. Because that's actually what it is: an outer casing of silica with two halves, one of which fits over the other exactly the way a petri dish lid fits over the bottom of the petri dish. If you place a petri dish on a table and look down on it, you will see a circle. But if you pick up the petri dish and look at it from a side view, you will see a rectangle. If you don't believe me, go ahead and try it with any canned food item in your pantry. Coscinodiscus is the same. If it lands on the microscope slide lying flat, it will look like a circle; this is called the valve view because you are looking down on the surface of one of the two valves of the frustule. Most of time when we see Coscinodiscus we see it in valve view. Sometimes you get lucky and a cell remains "standing up" even after you drop a cover slip on top of your sample, and you see the cell as a rectangle. This is called the girdle view. So in the photo above, what you see on the left is a Coscinodiscus cell in valve view, and what you see on the right is the same type of cell in girdle view. Same object, two perspectives, and two shapes. By the way, this is the answer to the question posed in the previous post.
And this is what a valve view of Coscinodiscus looks like when you zoom in:
You can see some of the sculpturing on the frustule, and the beautiful golden-brown color of diatoms. The diatoms are related to the brown algae and share the same overall set of photosynthetic pigments, which explains why diatoms are often the same colors as kelps.
Another of the common diatoms around here are those in the genus Chaetoceros. The prefix 'chaet-' means 'bristle', and the cells of Chaetoceros have long bristles. Unlike Coscinodiscus, Chaetoceros forms chains. Some species form straight chains, others form spiraling chains, and still others form a sort of meandering chain that is embedded in a tiny blob of mucilage. The cells below are forming a straight chain.
In addition to all of the diatoms, there were more dinoflagellates than I expected to see. Ceratium was very well represented, often in chains of two cells.
I was even able to capture some video of Ceratium cells swimming in the thin film of water under the coverslip. Dinoflagellates have two flagella: one wrapped in that groove, or "waistline", and one that trails free. Usually it's the trailing flagellum that's easier to see, and if you watch you'll be able to see it in each of the cells.
Protoperidinium was another common dinoflagellate in the sample. Unlike the diatoms and photoautotrophic dinoflagellates, which have that sort of golden-brown color, Protoperidinium is a heterotroph. It eats other unicellular protists by extruding its cytoplasm out of the holes in its cellulose skeletal plates and engulfing prey, similar to the way an amoeba feeds. Because it does not rely on photosynthesis for obtaining fixed carbon, Protoperidinium comes in colors that we typically don't associate with photoautotrophs. Pink, red, and grayish brown are common colors. This time I saw several that were bright red.
So that's a glimpse of springtime in the ocean. Now let's look up!
Legend has it that the swallows return to San Juan Capistrano every year on March 19, which is St. Joseph's day. I don't pay attention to St. Joseph's day, but I do pay attention to the vernal equinox every year and keep an eye out for the return of our swallows to the marine lab. We get both cliff swallows (Petrochelidon pyrrhonota) and barn swallows (Hirundo rustica) building mud nests on our buildings. Last year (2021) the cliff swallows showed up first, with the barn swallows arriving a few weeks later; I remember being worried that they might not show up at all.
This year the swallows returned right on schedule. I saw my first barn swallows on the day of the vernal equinox, 21 March 2022.
They are so pretty! I haven't seen any nest-building yet, but did witness what might have been a territorial spat. The bird in the photo above is the one on the left that is retreating in the photo below
Look at that gorgeous outspread tail! Barn swallows migrate to North America from southern Mexico and Central America. The cliff swallows come all the way from South America; no wonder they're a little late arriving in California! I think they'll show up any day now, and both they and the barn swallows will begin daubing mud above doorways and under the eaves.
Somehow, no matter what else is going on and what the calendar says, it never feels like spring until the swallows are zooming around again. Spring is my favorite season, as there's so much going on, and I begin to feel energized again with the longer days. I have a busy spring teaching schedule and don't know how much time I'll have to do fun things like look at plankton for the hell of it, but will try to slow down often enough to take note of what's happening around me.
Date/time: Saturday 2022-02-19, 08:00-09:30 Location: Natural Bridges State Park Weather: Chilly (8.3C), as sun hadn't yet risen above the roofs of the houses nearby; very light breeze
For Day 2 of the 2022 Great Backyard Bird Count (GBBC) I went to Natural Bridges, not suspecting that I would be able to ID and count so many species literally just inside the park boundaries. I ended up dividing my observation period into three locations and spent about half an hour at each.
Observation spot #1: Just inside the park boundary on Delaware Avenue (see map below)
This weekend, 18-21 February 2022, are the four days of the Great Background Bird Count. This is a global community science project in which people go out and document bird life. The beauty of a project like this is that is available to anyone who has a window to the outside. Of course, anybody can look at birds any time. To participate in the official project, people need to add their observations to eBird, which is similar to iNaturalist only specific to birds.
Date/time: Friday 2022-02-18, 09:00-10:00 Location: Younger Lagoon overlook Weather: Sunny, with very slight overcast; no breeze at first, but light breeze after about 09:30
Canada goose (Branta canadensis): 6
Mallard (Anas platyrhynchos): 4 female, 4 male
Bufflehead (Bucephala albeola): 4 female
American wigeon (Mareca americana): 4 female, 5 male
American coot (Fulica americana): 12
Northern harrier (Circus hudsonius): 1
Red-tailed hawk (Buteo jamaicensis): 1
Red-winged blackbird (Agelaius phoeniceus): hard to say, but at least 20 lekking away in the field across the lagoon
Osprey (Pandion haliaetus), carrying a fish!: 1
European starling (Sturnus vulgaris): murmuration of ~100
Bewick's wren (Thryomanes bewickii): 1
Song sparrow (Melospiza melodia): 2
Yellow-rumped warbler (Setophaga coronata): 2 male
In addition to this tally of species, which is fine in and of itself but not all that interesting, I did get to see some interactions. The northern harrier is a perennial resident, and I often see it either perched on a fence post across the lagoon or soaring low over the fields. Today the red-tailed hawk was perched on a fence post, and I didn't see the harrier until it flew in several minutes later. The harrier crossed in front of the hawk, flying low, and flushed out a murmuration of starlings. It chased the starlings around for a little while, obviously not hunting them. And as much as I wish starlings hadn't been introduced to North America, the flow of a murmuration is fascinating to watch. Even a small one of about 100 birds is rather impressive. Anyway, the hawk on the fence post watched all this activity for a few minutes and seemed to be rather peeved by all the kerfuffle. It ruffled its feathers and flew off. The harrier flew away later, and the starlings kept up their murmuration until I left.
Over the past couple of weeks I've rented two super telephoto lenses, to see what all the hype was about. I mean, do I really need 500 or 600mm of reach? I had read up on the specs of such lenses, and one major drawback is the weight—1900 grams or more. Would I be willing to lug a beast like this around, and would I be able to use it effectively? You never know until you try, so I rented them. And, of course, it was foggy both weeks so I didn't have much opportunity to take decent photos. But since the entire point of renting the lenses was to see if I could use them at all, that was fine.
As part of the test-drive for the second lens, I went up to Waddell Beach to see if there would be any birds to photograph. It is migration season, and our winter residents will be arriving soon. Some of them, such as the red-necked phalarope, have shown up at Younger Lagoon over the past four weeks or so. It was really foggy at Waddell, remember, and I didn't have much hope of seeing anything remarkable. There were some gulls and whimbrels off in the distance. But it turned out that the stars of the show were blackbirds!
They were hard to miss, because there were 50-60 of them and they were hopping up and down like jumping beans.
This is a mixed flock of Brewer's blackbirds (Euphagus cyanocephalus) and red-winged blackbirds (Agelaius phoenicius). The glossy greenish-black birds are the male Brewer's blackbirds, and most of the brownish birds are female Brewer's blackbirds. Since both sexes were doing the hopping, I didn't think this behavior had to do with courtship or mating.
So yes, while most of the birds seemed to be Brewer's blackbirds, I did hear the liquid gurgling of the red-winged blackbird's song coming from somewhere in the flock. When I got home and looked at the photos on the big monitor, I did see some red-winged blackbirds. Here's a male, surrounded by other males red-wingeds and both female and male Brewer's blackbirds.
In this photo above the black birds are male Brewer's blackbirds. The brown birds without faint wing bars are female Brewer's blackbirds, and the brown birds with the wing bars are male red-wingeds. There were no female red-winged blackbirds in any of my photos. According to an article from Cornell's Bird Academy, the males spend the weeks leading up to springtime competing for territories, and when the females return from their winter migration they will choose mates based partly on the quality of the territory. Mid-September is too early for this kind of competition, though. We are just about up to the autumn equinox, but not near winter quite yet.
Back to the hopping. There's a clue in this photo about what I think was going on:
See that little fly? There were many such flies, most of which were lower on the beach gathering around the kelps and other wet detritus that had washed up. There were fewer flies up where the driftwood accumulates, though. Once again, it wasn't until I saw the pictures on my big monitor that I could figure out what those blackbirds were doing. They were hopping up to eat flies!
Here's a series of shots showing one of the male red-wingeds in mid-hop.
Looking up, just before the hop:
Up he goes! See the very edge of the red epaulette on his right wing? And all those flies?
Is he going to catch something?
After all that, I'm not at all sure if he actually got anything!
I don't have any hard evidence that the blackbirds (both Brewer's and red-wingeds) are catching flies. And while I was at the beach watching them hopping up and down I had no idea what they were doing. However, now that I've seen the flies in the photos, it makes sense that the birds would be hopping up to catch and eat them, especially since both sexes of the Brewer's blackbirds were doing the same thing.
In Morro Bay, CA, there is a stand of eucalyptus trees that has been designated a natural preserve. In 1973 the Heron Rookery Natural Preserve was established to protect great blue herons (Ardea herodias) as they nested. Since then other bird species have taken to nesting in these same trees. When we were there at the end of May we saw these species with nests in the eucalyptus trees:
Great blue heron (Ardea herodias)
Double-crested cormorant (Phalacrocorax auritus)
Great egret (Ardea alba)
Snowy egret (Egretta thula)
This particular rookery is not at all removed from human activity. It is right across the street from the municipal golf course and next to a hotel, and there is a walking/biking trail that runs directly under the trees. Signs advise people to keep their voices down, but pedestrians are walking under the trees all day, dodging the rainfall of guano from above. The birds don't seem to be bothered.
Unlike the Brandt's cormorants (Phalacrocorax penicillatus), which nest on cliffs and rocks, the double-crested cormorants nest in trees. Birds build nests with local materials, and there is a difference in what I could see making up the nests of these two species. The Brandt's cormorants at Natural Bridges in Santa Cruz were using seaweeds as the main building material; I could see birds flying back with algae in their beaks, and then either handing it off to a mate on the nest or tucking it into the existing structure itself. In some cases I could see the pieces of algae well enough to make a tentative ID.
Those are the Brandt's cormorants. The double-crested cormorants nest in the trees, as we saw at the heron rookery. Here's a pair that have a brood of three chicks:
At Morro Bay, which is an estuary rather than a rocky area, the double-crested cormorants use a lot of eelgrass (Zostera marina) in their nests. Eelgrass is very abundant in the Morro Bay harbor and Estero, whereas the birds would have to fly a bit farther to gather algae. Eelgrass, being a true plant, is less slimy than the algae are, and these cormorants' nests look much drier than the mounds of algae used by the Brandt's cormorants up in Santa Cruz.
A short distance up the coast at San Simeon the double-crested cormorants were nesting in a smaller rookery, also in eucalyptus trees. I liked the pattern of how these four nests were situated in three-dimensional space:
Returning to goings-on at the heron rookery in Morro Bay, the herons and egrets were also raising youngsters in that stand of eucalyptus trees. Remember, this rookery is very easily visited by humans. Here's a view of the trees, taken from the small parking area:
It's difficult to photograph the nests because of all the branches obscuring the view. We were also there near mid-day, with the overhead sun making lighting conditions less than favorable for good photography. I did find one comparatively visible heron nest, containing one parent and one sullen punk-ass teenager of a chick. The nestling had started growing feathers but was still almost half fluff, clearly not ready to fly yet.
Both great egrets (Ardea alba) and snowy egrets (Egretta thula) nest at the heron rookery. Here's a great egret nest with two chicks:
From what I could see, the herons and egrets don't use any marine material at all to build their nests. One factor that determines the suitability of a potential building material is proximity—even if a certain material is fantastic in other ways, birds may not use it (or may use less of it, compared to other materials) if it costs too much energy to fetch and bring back to the nesting site. For the herons at this site, sticks are easy to come by. Another thing to consider is that herons and egrets are not marine birds. Although some populations live and nest in coastal areas, most do not. Thus it is not surprising that their nests are built from materials that are terrestrial rather than marine.
I did not see any snowy egret nests in areas where they could be photographed well. However, there were some adult snowies in their spectacular breeding plumage. There was enough of a breeze to ruffle up those long plumes that used to be harvested to decorate ladies' hats.
Look at these beautiful birds!
For several decades now, the cormorants, herons, and egrets have been nesting in these eucalyptus trees, which brings to mind the consideration of native versus non-native species. The trees themselves, blue gum eucalyptus (Eucalyptus globulus) are non-native, having been imported to California from Australia starting in the 1870s. This introduction was encouraged by calls to replace native trees that had been cleared for fuel and building material, both of which were desperately needed during and after the Gold Rush. Since ecologists began considering the effects of non-native species in the 1980s there has been a backlash against the blue gums. Given their large size, their having been planted in groups to serve as windbreaks, and their propensity for dropping a lot of debris, they are very conspicuous, and it is easy to get all hot and bothered at how in certain places they dominate the landscape.
At which point, however, does a species cease to be considered non-native? Having been established in California for 150 years, what is the role of E. globulus in the ecology of the Golden State? There are many people and organizations that would like to see the blue gums eradicated, or at least their populations greatly reduced. On the other side of the argument, groups such the San Francisco Forest Alliance posit that blue gums should be treasured as heritage trees.
At the Heron Rookery, some of the eucalyptus trees are dying. One reason is sheer old age. Another is the several decades' accumulation of bird wastes onto the soil, which is slowly killing the trees. As the blue gums die, the birds will have to find other places to nest. One of the pro-eucalyptus arguments is that many species of native birds—not just these here but other species such as red-tailed hawks, red-shouldered hawks, and a whole host of songbirds—nest in eucalyptus trees throughout the state. If the blue gums are removed, then where will these undoubtedly native birds nest? Especially if the native trees have long been gone?
Taking the long view, my guess is that the birds will figure it out. Ecological communities evolve over thousands of years. The 150 years of the eucalyptus trees' presence in California seems like a long time, but in terms of ecological time they are merely a blink of the eye. The herons, egrets, and cormorants have been nesting at the Heron Rookery for an even shorter period of time. When this stand of blue gums is gone, due to either natural attrition or removal by humans, the birds will find another place to nest. They might not choose a place that is so easily visited and observed by people, though.
It never really feels like springtime until the swallows have returned to the marine lab. This year the barn swallows (Hirundo rustica) came back right on schedule in the last week of March. They have been flying around ever since. I've seen them gathering mud on the banks of Younger Lagoon, but they haven't been very serious about nest building. The cliff swallows (Petrochelidon pyrrhonota), on the other hand, were late arrivals, and I was beginning to worry about them. I didn't see the first cliff swallow until the 1st of May.
Unlike the barn swallows, the cliff swallows immediately started spackling mud on the buildings. There have been a few aborted attempts, but overall they have been very busy little birds. I've been keeping an eye on one nest in particular, as it seems to be the one progressing most rapidly. This nest is located on a building that has been used every year, by both barn swallows and cliff swallows. In previous years I've seen and photographed the nests side-by-side. There isn't any reason to expect them not to nest together again.
So here's what has been going on so far.
The first stage is a simple shelf of mud. The birds are building on vertical walls, but corners where they can use two walls are prime locations. Even a tiny ledge can be used to support those first splats of mud, and once the mud dries it becomes foundation for additional layers. See the mud in the swallow's beak?
Sometimes the birds get this far and then decide to abandon the nest. And sometimes they keep going. Here's what's going on less than a meter away from this nest.
Notice how the birds use their tails as braces so they can cling onto vertical walls. Woodpeckers do the same thing. Of the four birds in the photo above, the two outer ones look like they're just starting to build. I've seen two birds flying in and out of that larger nest, but have no idea whether or not they're the same two birds every time. I suspect they are a mated pair.
The cliff swallow's nest is the gourd-shaped one, with a body that narrows to a much smaller opening just big enough for one bird to pass through. When the nest I was watching got to the stage in the photo above, I thought the opening would be on the left, since there's already a nice curve along that side of the front edge.
I might be kind of right. Today the opening is much narrower, and located off-center towards the left.
This nest may be finished tomorrow or the next day. It will have taken the birds about a week from start to finish.
Why are there no birds near the nest, you may ask? Well, when I walked out of the building I noticed that all of the swallows were in the air, and nobody was at the nest site. The birds were making alarm calls and flying around, but it didn't look like they were feeding, and none were returning to the nests even for short visits. I looked around and up and found the reason for the swallows' unrest.
The hawk was perched directly across from the swallows' nest site, and the swallows were not happy about it.
(For some reason the embedded video isn't working right now. You can watch it from YouTube directly by clicking on that link in the lower left corner.)
Some of the swallows flying around the hawk were barn swallows. I think they are nesting in the breezeway of the building under the hawk. Anyway, the hawk's presence was obviously upsetting to all of the swallows. It hung out for about 10 minutes and then flew away over the field. And immediately, the cliff swallows got right back down to the important business of building a home for the next generation.
The other day I was on a field trip with a couple of students in the Natural History Club, at Younger Lagoon. We had permission to go down into the lagoon itself, where we chased tiny red mites around rocks in the intertidal without getting caught by waves, observed a very interesting interaction between a coyote and assorted water fowl, and witnessed killdeer mating. Did you know that in killdeer the actual copulation is preceded by about half a minute of massage? Neither did we! The purpose of the field trip, other than merely to be outdoors looking at cool stuff, was to spend some time doing focused nature journaling. As a result I didn't have my big camera with me. But I did have the good binoculars, and got to watch all of the action closely.
Nature journaling should be part of any natural history club. Over the years I have seen an increase in the tendency to equate nature journaling with science illustration or other types of art. This conflation is what causes people to believe that they can't keep a nature journal because they don't produce museum-quality works of art. While I appreciate a beautiful science illustration as much as anybody else, a nature journal serves a completely different purpose. A nature journal's job isn't to be beautiful. Its job is to be informative.
If you were to compare my nature journal entry with a photograph of the site, you would see that my sketch is nowhere near realistic in the sense of looking exactly like the real thing. I've compressed the entire lagoon into a short stretch that I could fit in these two pages. But I think the sketches and notes do convey the fascinating things what we saw that day. And even if I were not familiar with Younger Lagoon, I would be able to look at these pages and remember them. That's the job of a nature journal.
I returned to Younger Lagoon two days later with the camera in tow, hoping that some of the birds we'd seen on Monday would still be there on Wednesday. In addition to the usual Canada geese and mallards, I hoped to shoot a couple of water birds that I didn't recognize.
Let's start with the obvious:
All told, there were a couple dozen Canada geese, in the water, in the air, and on the sand. They were a noisy bunch, as usual. Except for when the coyote showed up. Read that little story in my nature journal.
Now take a look at these geese:
See the one goose that doesn't belong? That was the mystery goose I saw on Monday, and was fortunate enough to see again on Wednesday. From the photos in my bird field guide—National Geographic Field Guide to the Birds of North America—I thought it might be a greater white-fronted goose (Anser albifrons), although I couldn't be entirely certain. I knew I hadn't seen one before, but a consultation with Cornell's All About Birds verified the ID. iNaturalist shows only a handful of observations of A. albifrons in the Monterey Bay region. The greater white-fronted goose is a long-distance migrator, breeding on the tundra of the high Arctic and overwintering in California's Sacramento and San Joaquin Valleys and the Gulf coast of Texas and Louisiana.
A third goose, and another winter-only bird, is the snow goose. It is a little bigger than the greater white-fronted goose. While the word "snow" implies white plumage, snow geese also come in a blue form, which is a dark blueish gray with a white head. The blue coloration is due to a single gene, and the allele for blue is incompletely dominant over the allele for white. The blue and white morphs are the same species and interbreed freely. The offspring of a pure blue bird and a pure white bird will be dark, but may have a white belly. Goslings from pure white parents will be white, and those from pure dark parents will be mostly dark but may have some white.
Of the two snow geese in the photo, the one in the front is all white except for the black wing tips of the species, while the one in the back has more dark coloration. In the photo the beak looks dark, but in better light it's as pink as on the bird in the front.
So that's three species of geese. Now whose butts are these?
These tails belong to American wigeons (Mareca americana), a male and female pair in the background and a lone male in the foreground. As you might guess from the behavior, wigeons are dabbling ducks, foraging on aquatic vegetation. Like the greater white-fronted goose and snow goose, these are also winter visitors to California's waterways, and will soon be headed north.
In their winter plumage, the wigeons are rather dull. The breeding male has a brilliant green patch extending backwards from his eye and a broad white streak from the top of the bill over his head. During the winter the green patch becomes is much less conspicuous, although the white streak remains.
Three species of waterfowl. I couldn't get the snow geese to cooperate and make up the quartet.
Living as we do along the Pacific flyway, we find that spring and autumn are great times for watching birds as they migrate between summer breeding grounds and wherever they overwinter. Sometimes I think it's rather unfortunate that I don't get to see these birds in the glory of their breeding plumage, but that's okay because I get to see them in the winter. And the birds that left here for the winter are returning: I saw the first barn swallow of the season right after the vernal equinox! Soon they and the cliff swallows will be building their nests on the buildings at the marine lab. At home, the first of the season's hooded orioles flew past the back deck. He may have been on his way to a nesting site in a palm tree down the street. There is so much going on right now. I do love the spring!
During what has become my daily check to see what's going on in Younger Lagoon, I got totally lucky and was able to see and photograph lots of birds. A morning with mostly cloudy skies meant good light for picture-taking. So I took lots of pictures! Some of these are series and need to be viewed in order to see the action. Sure, I could have just shot videos, but where's the fun in that? Sometimes still photos show a lot more than video.
It was a great day to watch wading birds! Legs and beaks come in varying lengths, and a particular species' combination of beak length and leg length determine where and how the bird forages.
While the long-billed curlew (N. americanus) has the longest beak-length-to-head ratio of any bird, the marbled godwit and whimbrel also have impressively long bills. In the photo below, the three birds with slightly downcurved beaks are whimbrels (Numenius phaeopus) and the one bird with the two-toned straight beak is the godwit (Limosa fedoa). Most of the godwits I've seen have beaks that are a smidge upturned, but this one looks pretty straight to me.
All of these birds forage by probing the sand with their beaks. All sorts of infaunal invertebrates are taken, and the mole crab Emerita analoga is a favored prey item. Obviously a longer beak allows for deeper probing in the sand, and the variation in beak lengths among the shorebird species may allow for niche partitioning. In other words, a long-billed curlew can reach down for prey items that are unavailable for birds with shorter beaks. The flip side of this equation is that birds with the "short" beaks might be better at picking up prey buried that are buried at shallow depths.
Prey are also distributed patchily along the beach itself, from the surf zone to the dunes, and these birds forage in the entire range. The length of the legs determines how far down into the surf zone they can go. When the beach is steep, as it is now at Younger Lagoon, the birds don't have much time to dig around in the surf zone before the next wave comes up. Click through the slide show to see this group of godwits, curlews, whimbrels, and a snowy egret react to an oncoming wave. It's important to note that while these birds do have some waterproofing in their feathers, they do not swim. Nor can they take flight if their feet aren't on the ground. Getting swept up by a wave and carried off the beach would likely be deadly for them.
The long-billed curlew is a favorite of mine, because I can't imagine what it would be like to go through life with a 2-meter beak sticking out of my face. They are fun to watch, and can probe remarkably fast with that long beak. This is one of the phenomena that is best shown by video.
You can watch how the birds forage within the surf zone, as in the slide show above, and also how long-billed curlews probe the sand higher up the beach.
These long-legged wading birds also feed in protected bodies of water and estuaries. All of these species can be seen at Elkhorn Slough as well as on the open coast, as one would expect from the Slough's position along the Pacific Flyway. Some birds migrate to California from far away. Marbled godwits, for example, spend the summer breeding season in the interior regions of North America, and winter along the Pacific, Gulf of Mexico, and Atlantic coasts. The long-billed curlew also breeds in the interior of the continent. Snowy egrets, on the other hand, are year-round residents.
I am grateful to have access to places like Younger Lagoon, where I can spend time outdoors without other people around, remove my mask, and take pictures of birds. I love that the Younger Lagoon Reserve has so many different habitats to explore, from ocean to beach to dunes to coastal scrub, in a small area. Fingers crossed that sooner rather than later, we'll be able to once again bring students there to study the natural world in the Reserve's outdoor classrooms.
Still more or less under quarantine shutdown due to COVID19, I haven't been doing much outdoor stuff over the past several months. What with the pandemic and horrid air quality due to wildfires throughout the state, spending time in places I would normally like to hang out simply hasn't been possible. We're still getting too many out-of-the-area visitors for me to feel comfortable being around people, and weekends are especially bad. But last weekend I went to Moss Landing to take pictures of birds and other wildlife—I needed visual aids for a virtual lab my students will be doing in a few weeks.
It's the time of year for birdwatchers to get excited about winter visitors. I've had golden-crowned sparrows in the canyon behind the house for almost a month now, but I hadn't been down to a beach in a while. Moss Landing is a great place for birdwatching, because you can explore the estuarine habitat of Elkhorn Slough, the sandy beach, and the harbor during a 2-mile walk. That's three distinct habitats for very little effort!
Starting at the tidal marsh, I always keep an eye out for the long-billed curlew (Numenius americanus). They have the largest beak-to-head ratio of any bird.
One of my favorite winter visitors to the marsh area is the willet (Tringa semipalmata). Unlike most shorebirds that are speckled or mottled, willets in winter plumage are a beautiful soft gray-ish brown color. Every time I see a willet I ask myself, "Willet, or won't it?"
And when they take off in flight, willets show these striking black and white wing patterns. They always take me by surprise, even though I know to expect it.
A whole flock of willets taking off at once is quite an impressive sight!
From the marsh it's a short walk over the dune and onto the beach.
I always look forward to walking this beach because of the dead things. Don't get me wrong, the living things are fun to see, but in some ways the dead critters can be more informative. For every species there is always some baseline level of mortality in the ocean, so you expect a certain number of dead things to wash up. However, an unusually high number of corpses could indicate that something is going on at sea. This trip I didn't see very many dead critters: just a few grebes that had been there for a while, nothing out of the ordinary.
Oh, and an otter pup. At least, I'm pretty certain it was an otter.
Yes, we came across a dead sea otter pup, my first ever.
The body was missing a head, but the parts that remain were a bit longer than my booted foot. Although most of the soft tissue had been scavenged, the carcass had distinct paws, meaning it wasn't any kind of pinniped (seal or sea lion). Also, pinnipeds don't have fur like this, as they rely on blubber for thermoregulation. Sea otters, on the other hand, have the densest fur of all mammals, with the oft-cited 1 million hairs/in2.
But let's be honest. I like the beach because I like photographing birds, and there is always interesting bird life at this beach. I'm not one of the crazy bird people who keep a life list and need to be the first person to spot a particular something-or-other. And, unlike the idiots I saw tramping through the pickleweed in pursuit of a Say's phoebe that day, I don't climb over fences and trespass where I'm not supposed to be. Besides, even the everyday backyard birds are fun to watch. Whoever says that familiarity breeds contempt certainly is not a naturalist!
And who doesn't love a snowy plover or two?
The snowies aren't nesting at this time of year so the upper part of the beach isn't roped off. They do still get disturbed by people wandering around, who probably don't even know the birds are there. They (the snowies, that is) are so tiny that when they hunker down behind a divot in the sand they disappear completely. If you sit or stand quietly, they will pop up and make short dashes from hillock to pile of beach wrack and back again, feeding on the insects and crustaceans they find.
In addition to the snowy plovers, another tiny "peep" bird runs around on the beaches, often in large groups. These are the sanderlings, Calidris alba. I've only ever seen them in nonbreeding plumage, as they nest in the high Arctic.
Sanderlings are the little birds that run back and forth from the waves. As a wave recedes the sanderlings frantically stab their stout beaks into the sand, grabbing up small mole crabs and other crustaceans that are right at the surface. When the next wave arrives the sanderlings run back up the beach. They have short legs and don't swim, so getting swept out to sea would be a very bad thing for them.
Sometimes even the long-legged shorebirds forage on the beach. I've seen the curlew there, as well as whimbrels and godwits. This day the godwits were stealing the show.
The godwits, with their longer legs, are able to stand their ground when the waves wash up. They can catch food that is buried more deeply into the sand. On mudflats they pick their way over the flat at low tide, digging for worms, clams, and crustaceans. They can feed on a mudflat only at low tide. But on the beach they can feed at any time, just moving with the tide as it floods and ebbs.
And my friend the long-billed curlew was there on the beach, too!
The curlews are not as eager to forage in the waves themselves as the godwits seem to be. The curlews might wander down to where their ankles are swashed by the waves, but do not seem to like getting wetter than that. But that bill can probe very deeply into the sand or mud. I've watched them feeding on mole crabs on the beach, and on worms on the mudflats.
Autumn and winter are good times to watch birds around here. There's a bit of a lull in bird activity once the swallows leave depart for the south and before the winter residents show up. For me, autumn begins when the golden-crowned sparrows arrive in the neighborhood, which this year was September 25. I'm listening to them now as I write this! Being located on the Pacific Flyway means we get lots of birds resting for a bit on their migration even if they don't winter here. I'll try to get out to Moss Landing during the winter months, to keep track of the avian comings and going.