Tuesday, February 27, 2018

Bow to Your Reptilian Overlords! Oh, Maybe Not Quite Yet...

The desert is filled with creatures that are dangerous and terrifying in their ways. Life is tough, and in short, everything that lives there is eating everything else, and everything else is trying not to be eaten. Life has evolved a huge variety of defensive adaptations, including spikes, spines, tough shells or out layers, poisons, and many others. We were in Death Valley last weekend, and early one morning I seemed to have discovered a terrifying new creature, one whose claws look almost dinosaurian.
Those terrifying claws actually are dinosaurs, although of the avian kind. Few birds were out and about during our visit, but the Common Raven (Corvus corax) was a constant presence. That they thrive in this harsh and barren world is a testament to their versatility and intelligence. If I had to predict the species that would evolve into the dominant organism in terrestrial environments after the humans obliterate themselves, my money is on the raven. Like humans, they are curious, they are opportunistic omnivores, they are toolmakers, and they are problem solvers. And they can live in a shocking range of environments from the icy shores of Arctic Canada, Alaska and Greenland, to the driest and hottest deserts of the American West. Their range extends into the rainforests of Central America.

Their black color sometimes makes them hard to photograph, but in a desert setting like Death Valley, it becomes more of a goal to place them within dramatic landscapes. From our camp at Stovepipe Wells, we had a beautiful morning view of the Cottonwood Mountains. A pair of ravens were flying in the distance.

Our last 24 hours in Death Valley National Park involved a violent windstorm. It briefly subsided while we packed to go home, but the wind started up again, and the dust storm rose over the Mesquite Dunes in the distance. A Raven seemed to be heading out to investigate...because that's just what our future overlords would be doing.

Great Horned Owl Nesting on the Tuolumne River Parkway Trail

I've been a little frustrated that I've never seen an owl on the Tuolumne River Parkway Trail in the three years I've been exploring the pathway. One just knows they have to be there, given the rich food sources along that stretch of river. I finally heard one downstream of the stairwell at the west end of the trail a week or two ago, but still no sightings.
Yesterday, however, was a most extraordinary day, because in two hours I saw 38 bird species, including a few that I identified for the first time ever for the area. And among them, much to my pleasure and surprise was a nesting Great Horned Owl (Bubo virginianus). There isn't much drama in the pictures, and in a nesting situation one doesn't really want drama, but it is neat to know that we'll be seeing some young owls in coming weeks. I'll try to keep you posted on their growth.

UPDATE (3/4/18): Well, drat. I went back to check out the nesting site a week later only to find that it had collapsed and fallen to the ground, I presume during last week's harsh storms. Does anyone know if Great Horned Owls will try nesting again in such circumstances?

Monday, February 26, 2018

Rock Wren at Kern River County Park near Bakersfield

I spent last week in Death Valley National Park, and although logic would seem to dictate that there would be few birds about in the driest place in North America, but there are in fact a few. In fact, in the right circumstance, there are a great many species, many of whom are passing through on their migrations elsewhere. But I didn't see all that many of them.
Before we reached Death Valley, we made a stop at Kern River County Park to look for a few fossils. While I was scouring the hillside, I noticed that there was a bird doing some "people-watching". It turned out to be a Rock Wren (Salpinctes obsoletus). I've seen them a few times back home around Turlock Lake, but that's about it.
The Rock Wrens range across the west from the Canadian border to deep into Mexico and Central America. They eat mostly insects that they glean from spider webs or catch on the fly. They are declining in number because of habitat loss.

Friday, February 23, 2018

Red-tailed Hawk Hovering for Dinner at the San Joaquin River National Wildlife Refuge

I always try, but I rarely get good pictures of hawks or eagles in flight. It's not easy to focus in on a moving target and get much of a picture, but today was a little bit different. There was a Red-tailed Hawk (Buteo jamaicensis) hovering, or kiting, over the empty fields around the viewing platform on Beckwith Road (part of the San Joaquin River National Wildlife Refuge). It was hovering in place long enough to get focused in. It didn't get any dinner while we watched, but it wasn't for lack of trying.
Things were pretty quiet otherwise at the viewing platform. We saw dozens, maybe a hundred or two of the Sandhill Cranes off in the distance, but no geese. It may be that they were out foraging for food, but it is also possible that they have begun the journey north to the Arctic. The viewing platform usually closes in March when the birds are gone.

Tuesday, February 13, 2018

Oak Titmouse on the Tuolumne River

Here's a fairly rare visitor to my blog pages. I've only captured semi-decent pictures twice in the past, once at MJC, and once in my backyard (!). On my walk the other day along the Tuolumne River, I saw an Oak Titmouse (Baeolophus inornatus) perched on the Elderberry bower where I've seen a multitude of bird species. I've been able to stand inside the "bower" and have birds landing all around me. Today I was still approaching the shrub when I saw the silhouette of a bird with a crest. That usually means Phainopepla, but this one was too small. Therefore it had to be the Titmouse. It was most polite and remained perched for a dozen or so pictures.
"Be sure to get the left profile; it's my best side"

The Oak Titmouse is essentially a California endemic species, with populations in Baja (which is California, despite the international boundary). They spill over into Oregon a bit on the north end of the state. They are closely associated with the vast oak woodlands that cover the coast ranges and Sierra Nevada foothills. There is a closely related species, the Juniper Titmouse (they were once considered the same species), but there are specific differences, and the two populations are geographically separated by the Sierra Nevada (there is only a small area of overlapping range). Once again, this allows us to see evolution in action: the birds have diverged in part due to the different vegetation in the higher, colder and drier Basin and Range province beyond the Sierra Nevada.

Sunday, February 11, 2018

Bird-Watching in (Semi) Urban Settings: Part 3, the Tuolumne River Parkway Trail

Many people who blog do so from a position of knowledge, i.e. they are already experts at something, and they are deigning to pass their wealth of knowledge to us, the unwashed masses. I might do that over at Geotripper, but here on my "hobby" blog, you are witnessing my education on birding in real time. In no way would I call myself any kind of expert, but I do enjoy photographing these little creatures and sharing with you what I learn (and I know I have gotten things wrong; I keep waiting for an expert to go through my old posts and send me corrections!). In any case, I'm carving out a little niche of the county as my "territory", and that is obviously the Tuolumne Parkway Trail that follows the river through Waterford. Lately I'm trying to be a bit more disciplined about recording bird species and reporting them to eBird. It is one of the less traveled places in the county for birders as the trail only opened in the last two years. Several experts have made a number of reports, most notably Siera Nystrom of the great blog Natural History Journal, but with 85 noted species thus far, I know the potential exists for a great many more discoveries (our county has recorded more than 300 species after all).
The Tuolumne River Parkway Trail follows two miles of the river from Appling Park and the River Pointe housing development west to a stairwell that climbs the bluff to Reinway Park. The trail was dedicated in 2016, and from a birding perspective, it offers a wide variety of environments in a short distance. The stretch of river is part of the transition from the Sierra Nevada foothills and the floor of the Great Valley, and as such provides an avenue for the flow of species from the mountains to the valley and vice versa. The town of Waterford (population around 9,000) lies above on the bluffs over the river, providing a constant flow of urban bird species. The river itself is a rich riparian habitat with occasionally dense thickets of willow, cottonwood, native fig tree, non-native Tree of Heaven, and some tremendous old Valley Oak Trees. Ponds left over from the gold-mining and quarrying days provide a lake environment for geese, duck, and even a couple of swans. And, as gross as it might seem but isn't, the water treatment plant for the town provides another pond-like environment (the richest species habitat in all of Stanislaus County is the sewage treatment plant for Modesto, with more than 200 species). All in all the potential exists for the discovery of the many more species in coming years.
Geologically, the river cuts through a series of layers exposing evidence of ancient rivers and volcanic eruptions, as well as periods of increased water flows during the more recent Pleistocene ice ages. It was the cessation of glaciation that allowed the Tuolumne to carve down through the older sediments producing a series of bluffs as much as 80 feet high. These bluffs protect the city of Waterford from floods.  On the other hand, when floods do happen, the river is constricted and covers the floodplain under many feet of water, sometimes for months, as was the case last year during our record precipitation year. Trees and shrubs were torn out and left in gigantic brush piles. Sediments were redistributed across the valley floor.
The Gold Rush of the 1850s had a profound effect on the river as vegetation was torn out and river sediments were processed for the yellow metal. The natural channels disappeared, and critical fish habitat was destroyed. Later on huge quarrying operations removed vast amounts of sediment leaving behind the ponds mentioned above, fed by groundwater, and often stagnating during hot summer weather.

In the modern era, including most of the nearly thirty years that I've lived here, the river was mostly ignored, hidden behind private property lines. The bluffs were used as a dumping ground, and there was little recognition of the little treasure in the midst of our community. It wasn't until the last decade that the idea grew to construct a public trail along the river and the city sought and received grants to build the pathway. It's been a success, as people can be found fishing and jogging/hiking along the river all the time.
I hike the trail three or four times a week, getting some much needed exercise, and building a list of bird observations as well as the other creatures that call the river home. Officially I've seen 55 species (the ones I've so far reported), but the actual number is more like eighty. I've also seen and photographed Red and Gray Foxes, River Otters, and Raccoons, and I'm waiting to sight the California Golden Beaver that's been chewing up trees at my favorite sitting spot.

If this post seems a bit different than the usual, it's because I realized the margin information on the blog hadn't been updated in a long time. When I started the blog in 2014, I made most observations at school, or in the pastures near my house, since I didn't have access to the river. That's changed now in a big way, and most of the birds I report on are on or near the water.

Saturday, February 10, 2018

Ruby-crowned Kinglet on the Tuolumne River...with a Ruby Crown!

Little birds are hard to photograph. It's just that simple. It seems the smaller they are the more active they are (think hummingbirds). Well, here's a bird that is barely bigger than a hummingbird, and although it is common in the bushes along the Tuolumne River, it's harder than heck to get good shots. It's called a Ruby-crowned Kinglet (Regulus calendula), and I have wasted loads of digital space trying to get decent pictures. I salute anyone who got great pictures of these birds in the days of photographic film!

I got tempted into trying to get a shot once again on my river walk today, and the results were the same as always, blurry or nothing at all. Then the impossible happened...the bird paused. Even though we were in the shadows, I got a few shots in focus and up close. The bonus was that it was a male, and I got a half decent shot of the usually hidden "ruby crown". The red feathers are most often displayed during the breeding season when the male is showing off.

Next time? Let's do this in the sunshine!

Friday, February 9, 2018

Pied-billed Grebe on the Tuolumne River Parkway Trail

If it seems like you've heard of Pied-billed Grebes (Podilymbus podiceps) a lot lately on this blog, you would be right. I've been doing this blog for almost four years now, and I've mentioned Pied billed Grebes just four times, but two of those have been in the last three weeks. And now again today. Why? They've appeared on my section of the Tuolumne River, the Parkway Trail, and they've just been daring me to take pictures. This one was in the slough at the west end of the trail, and the sun angle and ripples on the water combined to make a memorable scene.

They are very shy, but as I walked back towards the stairwell, I was able to get a closer shot of the bird in the willow thickets. I've been watching the river along the trail carefully for two years now, so it seems to me that I would have noticed these birds if they were present, but I never have until last month. The newly arrived Common Goldeneyes are also still hanging out. Today they had moved downstream to the pond across from the stairwell at the west end of the trail.

Wednesday, February 7, 2018

Strange Looking "Geese" at Goose Day on the San Joaquin River National Wildlife Refuge

Um...those don't look like geese to me...
The San Joaquin River National Wildlife Refuge is a marvelous bit of the (almost) original landscape of the Great Valley of California, combining prairie and riparian habitats in support of hundreds of thousands of migratory waterfowl. There is a four mile long hiking trail in one sector of the refuge, but only a viewing platform at the other, at the end of Beckwith Road a few miles of west of the town of Modesto. I have seen incredible sights from the platform and from along the road, but it's always been sort of a mystery as to what lies in distance, the places where the public is not usually allowed to go.
Last month, we were given the chance to find out. The refuge sponsored their first ever Goose Day celebration on January 13, and the festivities included an auto-tour into the interior of the preserve. The managers expected two or three dozen people, but got 100-200 people instead. The group worked out caravanning and dozens of cars motored their way into the refuge.
The ironic part of course is that few geese were in attendance (who could have foreseen that?). I don't think anyone who was there was disappointed. Their interest was in all of the birds who call the refuge home, and the chance to see the interior up close. Aside from a few comments about how cold it was, I heard no complaints. The most visible of the "charismatic" birds were several dozen American White Pelicans (Pelecanus erythrorhynchos) on an island in Page Lake.
The pelicans famously scoop up fish in their bill, although they do not store them there (they swallow them right away). They don't dive like Brown Pelicans, but instead will hunt cooperatively, swimming along in a group herding the fish ahead to where they can scoop them up.
The Pelicans are doing well. Their population crashed in the middle 1900s due to pressure from hunters and fishermen who feared the birds were consuming the valuable fish species (they weren't). DDT had an effect on populations as well, as did wetlands habitat loss. Their numbers are rebounding today.

The auto-tour spent around an hour on the shoreline of the pond in the midst of the refuge. We did see geese flying overhead, and we also saw a Great Horned Owl, Sandhill Cranes, Black-necked Stilts, Yellowlegs, and numerous other shorebirds. The tour continued on the other side of Beckwith Road, following the dike along the Stanislaus River across from Caswell State Park.
One can see why they don't want to have unrestrained public visitation. The road maintenance costs would be prohibitive.

After the tour I did in fact find a couple of geese, some Snow Geese along Beckwith Road a bit west of the viewing platform. There are in fact tens of thousands of geese in residence, but during the day they range across the region looking for food. They gather at dusk in huge flocks.
A few days later, things were back to normal, and I headed out the platform during an afternoon break. There were hundreds of Pelicans on the island, and perhaps several thousand Sandhill Cranes visible from the road.

Butterbutts: Yellow-rumped Warblers at MJC and the Tuolumne River show Evolution in Action

In the days of my ignorance (actually not a thing of the past), all small birds were sparrows of some kind. Imagine my surprise when I started paying attention and discovered the dozens of colorful and interesting birds that weren't sparrows (most of them). Among the most beautiful are the little Yellow-rumped Warblers (Setophaga coronata), apparently also known as...butterbutts.
These are pretty little birds right now, but in a few weeks they will take on even brighter plumage as the breeding season commences. I may not see them as often as they tend to move up into the forests at that time. Right now they are flitting about in the trees in great numbers on my campus (all the following pictures), and along the Tuolumne River below where I live in Waterford (the two pictures above).
There is an interesting story concerning these little birds. Until 1973, they weren't "Yellow-rumped Warblers". They were an eastern species called a Myrtle Warbler, and a western species called the Audubon's Warbler. There are color differences, and differences in their calls. But...in 1973 they were combined into a single species because of a narrow region where the range of the two species overlapped. In that narrow region the two species were observed interbreeding and producing young, a long-term definition of a biological species. So now they are officially considered to be subspecies along with two others, the Black-fronted Warbler in Mexico, and the Goldman's Warbler in an isolated part of Guatemala. They're all Butterbutts, for the time being.
But change is afoot. Genetic research is far more advanced than it was in the 1970s, and DNA evidence indeed suggests that the four butterbutts should be considered species rather than subspecies. Part of the argument involves that fact that while they hybridize in that small zone of range overlap, the area of interbreeding has not expanded over time, as if the hybrids were not really viable.
These birds are a great example of how natural selection and evolution works to change and develop new species. As with the Scrub Jays that I discussed the other day, isolation is the driving force leading to changes. During the ice ages, the original populations of the warblers were separated by glaciers, and they remained isolated in the aftermath. The populations were subjected to different environmental conditions and different food sources, and over time little differences developed. Some of the variations allowed particular individuals to survive and pass on their genes to subsequent generations, and over time, the differences accumulated to the extent that they could no longer successfully interbreed. In other words, they were new species.
Because of the new research results, the North American Classification Committee of the American Ornithologists' Union may very well declare the four subspecies to be species once more. It's arbitrary in one sense, but the fact that there are blurry lines between possible species actually supports the idea of evolutionary change. There are simply not always sharply defined boundaries as divergence takes place.
In any case, these beautiful birds may be right in your own backyard. In ours they stayed away from the feeder and hung out in the Mulberry trees around the corner of the house, so I never thought to search for them. Nowadays, knowing where to look, I see them all the time. Have I mentioned that they aren't sparrows?

Sunday, February 4, 2018

Tundra Swans at the San Luis National Wildlife Refuge

This was a rare event for Mrs. Geotripper and I. The Tundra Swan (Cygnus columbianus) is not a rare bird, but we've only seen them once before, and only for a few moments. Yesterday we saw dozens of them at the San Luis National Wildlife Refuge.

We were following the Waterfowl Auto-Tour at the main part of the refuge north of Los Banos, and while we got a couple of nice photos of birds here and there, overall there wasn't much going on until we approached the end of the loop.
There's a short detour at that point that leads to a trailhead for the Souza Marsh Trail. There were a couple of serious birders stopped on the road with tripods and telescopes deployed. I looked north and saw a large number of white birds in the distance and immediately suspected swans, since Snow Geese and the like wouldn't have captured their interest to that extent. We stopped too and a quick look with the zoom lens revealed dozens of Tundra Swans as well as hundreds of other birds representing at least nine or ten species, including Snow Geese, Greater White-fronted Geese, Northern Shovelers, Northern Pintails, American Coots, Pied-Billed Grebes, Great Egrets, and Mallards.
Tundra Swans, as their name suggests, breed in the far north Arctic lands and migrate south during the winter months. California's Great Valley provides an ideal winter refuge with moderate temperatures and plentiful food supplies.
Although the Tundra Swans are smaller than our other native swan, the Trumpeter (which is never seen in our area), they are huge in comparison to the geese and ducks. I took several videos of the swans, but I like this one because of the Greater White-fronted Geese who came floating by in formation on either side of the swan. It shows the size differential well.

The San Luis National Wildlife Refuge is one of a string of refuges along the river floodplains of the Great Valley that provides a winter home for migrants like the swans and geese, but also a natural habitat for our year-round species. I'm amazed at how little known they are even in our local area. We only saw two other vehicles on the loop when we were there on Saturday. It is a serene place to visit.
The refuge includes a beautiful new visitor center (along with the resident cat named Lucky) that is a good starting point for a visit. There are three auto-tours in the immediate vicinity and several hiking trails.