Wildlife in parking lots

 

Not great shots, but my first local images of a Beaverpond Baskettail (Epitheca canis).  This dragonfly was flying a beat, probably searching for food, around a parking lot in Occidental on 29 April 2014.

 

I'm grateful for interesting wildlife sightings in parking lots!

Pass it on

This afternoon, we noticed a raven washing a food item in a shallow fountain pool in Occidental:

 

Seconds later, another raven flew in, and the first bird passed the food item to the second bird!

 

They flew off, but returned later, and the same thing happened — the larger individual fed the smaller individual.  Here are two pictures showing that sequence:

 

 

Is this a male feeding a female?  Or an adult feeding a juvenile?  The smaller bird appeared all glossy to me, and I'd expect some duller feathers on a juvenile, but I don't have much experience judging the age of ravens.  Below is one more picture of both birds.  What do you think is going on with this interaction?

 

Cruising the creek

 

Common Mergansers (Mergus merganser) in Salmon Creek, 26 April 2014

Note that the male, with the greenish-black head, lacks a crest.  And the female, with a reddish-brown head, has a distinct white chin patch.

A small group of Common Mergansers was cruising along the creek, occasionally "snorkeling"— visually searching for prey (e.g., small fish) below the surface.

 

Several birds walked up onto a gravel bar and started to preen.  (I was impressed with their substantial legs and feet!  Don't they look strong?)

 

Common Mergansers have been documented nesting along the Russian River and Austin Creek, so perhaps they're starting to think about pairing up.

P.S.  Well, I wondered if it would happen, and now it has.  Life has thrown me a big enough curveball that I don't think I'll be able to keep up with a daily post right now.  It's my intent to keep posting when I can, but I wanted to let everyone know that it might not be as regular as it has been.  For those of you who subscribe to the blog e-mails, you'll still receive one whenever I post.  And of course, if you just check in to the Natural History of Bodega Head website every now and then, you'll see new messages whenever they get posted.  However, if you'd rather not wonder when there's going to be a new post, you can subscribe to the e-mails by scrolling to the bottom of the main page and looking for the section where it says "Follow by Email."  Just be sure to watch for the confirmation e-mail after you submit your address, as I've heard that it sometimes ends up in spam.

 

Lophophores and lace

Here's a nice marine invertebrate that I didn't get to show when I first photographed it in mid-March.

 

This cluster of white tubes was growing within a kelp holdfast.  The entire patch was small, only ~1 cm across.

I'll zoom in a few more times, because when viewed up close these animals are quite intriguing.

The picture below highlights the elongate white tubes on the right and also provides your first glimpse of the animals themselves.  On the left side, look for the rings of tentacles radiating out from the tube entrances.

 

Here's an even better view of those rings of tentacles, also known as lophophores:

 

This is a bryozoan called Tubulipora.  When feeding, the colonial animals extend their lophophores into the water to capture food particles.  But they can also retract their tentacles into their calcareous tubes (see diagram below).  When they do so, sometimes you can just barely see the tips of the tentacles near the tube opening or aperture (see picture following diagram).

 

 Modified from Invertebrates (Kozloff 1990)

 

Tubulipora belongs to the most ancient class of bryozoans known as the Stenolaemata.  They're known for having thin, porous walls (see below), and many, including Tubulipora, lack operculums (trapdoor-like structures that close off the tube entrances).  [For a picture of an operculum in another species, Eurystomella, click here.]

 

Although they just look like tiny white patches of lace growing on kelp when observed in the field, I hope this helps you visualize what these animals look like when they're out and feeding.

See-through

In mid-March, I was trying to photograph a small Sunflower Star (Pycnopodia helianthoides) that we had discovered rafting in a Bull Kelp holdfast.  Eric came along and looked through the microscope.  By the way he was taking a little extra time, I knew he was noticing something interesting.

He turned and said, "Those dark areas are the pyloric caeca!"

We had observed the way these small Sunflower Stars looked dark in the center (see below), but without looking closer, we had assumed it was pigment.  Now with a better view under the microscope, we could see that it wasn't pigment.  The body wall of the sea star was transparent, so we were seeing through to the inside of the sea star and actually viewing the digestive system!

 

Here's a diagram with an explanation (below).  A sea star has two stomachs — the cardiac stomach is the one you might be more familiar with; it's everted (extended outside of the animal) when the sea star is feeding.  The pyloric stomach is located above the cardiac stomach, and it has branches that reach into the arms.  These branches are called pyloric caeca (there are two in each arm).

 

Modified from Biology of the Invertebrates (Pechenik 2010) 

Many sea stars store energy in their pyloric caeca during the spring and summer.  In the fall and winter they transfer that energy to their gonads for reproduction.

When sea stars are older, their body wall is no longer transparent, so the pyloric caeca can't be seen.  It was a treat to be able to see both the polygon-shaped pyloric stomach and the pyloric caeca in this juvenile Sunflower Star!

(Note that the newest arms, the shortest ones, don't yet have pyloric caeca, but they will develop them later.)

 

My, what red feet!

 

 

On 18 April 2014, Eric and I enountered a nice gathering of Pigeon Guillemots (Cepphus columba) — at one point Eric counted 23 individuals.

Some guillemots were displaying in the water.  In the photo below, look for the bird with its head feathers raised (its head looks "puffy" relative to the others) and its tail held upright.

 

Occasionally one or two birds would take off and fly up to an offshore rock where it looked like they were investigating possible nesting sites.

The image below shows one guillemot in flight, with its white wing patches and bright red feet.  But there's another guillemot in the picture that's barely visible because it's tucked away in a crevice.  Can you spot it?

 

The second guillemot is in the upper right corner of the picture (see red circle below, highlighting the bird peeking out of the crevice and looking to the left).

 

A few fun facts: The males probably choose the nest site.  They defend a territory of about 1-4 square meters around the nest entrance. The females lay 1-2 eggs, usually some time between mid-May and mid-June.  Females and males will incubate the eggs for ~30 days.  It will take ~40 days for the young to fledge (after being brought many fish by both parents).  

And if you're wondering about those red feet — it's possible they're used in courtship displays.

[All facts from The Birds of North America account by Peter J. Ewins, 1993.]

It's green

We were walking up the Pinnacle Gulch Trail today, when Eric paused, looked down, and quietly said , "This one's different...it's green."

I couldn't see what his eyes were focused on at first, but then I finally spotted it:

 

We had been seeing quite a bit of butterfly activity along the trail, and then we were very lucky that he noticed this beautiful green hairstreak basking on a Phacelia leaf.

I didn't have a close-up lens on the camera at the time, but I did the best I could to take a few pictures before the butterfly flew off:

 

This is a Coastal Bramble Hairstreak, sometimes called a Coastal Green Hairstreak (Callophrys dumetorum).  [The taxonomy of this species is confusing, so you might encounter different common names and scientific names depending on your source.  I'm just listing what I'm seeing used most frequently right now.]

Coastal Bramble Hairstreaks are known for wonderful blue-green colors on the lower surfaces of their wings.

Their caterpillars feed on perennial buckwheats (Eriogonum spp.) and Deerweed (Acmispon glaber, formerly Lotus scoparius).

The adults fly between February and June, so watch for them if you're in the right habitat at this time of year!

I took one more shot before more hikers came along the trail.  I hope this encourages you to watch for this little jewel of a butterfly!  

 

Early morning flight

 

Just a quick shot of some Pacific Loons (Gavia pacifica), and one Common Murre (Uria aalge), heading north today.  There was an impressive movement of birds this morning, with a steady stream of loons visible off Bodega Head.  Can you spot the murre?

(The murre is the second bird from the left — smaller than the loons, with an all dark head.)

Last April I wrote a little bit above loon movements along the coast, so if you'd like to read that post, click here.

Can you tell it was windy when I took today's picture?  It was blowing about 14 mph out of the northwest, and the wind just kept picking up all day.  By 5:30 p.m., the ocean looked like this:

 

Spring in Blow-dega Bay!

Prospecting

As I was getting ready to leave for work this morning, a different sound in our backyard caught my attention. 

First I heard some high-pitched sounds, and then I heard some subtle low-pitched sounds coming from high in the trees.  I looked up to try to locate the source and was a little surprised to see a duck flying between the redwood branches!

I couldn't locate the duck again, but I kept hearing the sounds, so I continued looking.  Eventually my eyes landed on this:

 

If you look carefully in the picture above, I think you'll be able to see two ducks: a male and female Wood Duck (Aix sponsa).  The male is perched above the female.

The male turned, so here's a slightly better view:

 

The male and female separated, and kept flying from branch to branch.  It was dark among these trees, but below is a decent head shot of the male, and the best image I have of the female.  Note the different facial markings — the male with narrow white projections arcing up onto his cheek and neck, and the female with a white tear-drop shape surrounding her eye.

 

 

We've never seen Wood Ducks in our yard before.  I had lots of questions running through my head while watching them.  Were they looking for a place to roost for the day?  Were they evaluating possible nest sites?  Did they actually have a nest already?  Because they were calling the entire time, I even wondered whether they could have young that they were trying to coax out of a nest.  

Somewhat surprisingly, Wood Ducks can nest up to 2 kilometers away from water.  And if you haven't heard about their remarkable nesting strategy, here's a brief summary: They nest in tree cavities.  When the young hatch, the female calls to them, persuading the ducklings to leap out of the cavity.  They free-fall from the nest to the ground!  Once on the ground, the mother will lead the ducklings to a nearby wetland. 

Although I can't be certain, after reading about Wood Duck sounds, I'm wondering if this pair was scouting the area for a nest site.  The Birds of North America account describes nest-searching calls: for males, a multisyllable jibjibjib...and for females, a low-intensity multisyllable tetetetetetet.  The full description is a pretty good match for the two types of sounds I heard.

Here are two more pictures to document my first time seeing possible prospecting behavior in Wood Ducks.

The male peeking out from behind a large redwood trunk:

 

And this is an unexpected shot.  I meant to take a picture of the landscape, just to show the overall setting.  When reviewing the image, I realized that I also captured the male in flight!  This is probably going to be challenging, but perhaps you'd like to try to find him before I tell you where he is.  I'll give you a hint.  His wings are open and his belly is facing towards you (the belly color is buffy).  Look carefully and I bet you can find him!

 

[The male Wood Duck is in the lower left corner of the photo, just below a horizontal tree limb and to the left of the large redwood trunk.]

 

I have no idea if this Wood Duck pair will return, but if they don't, it was fascinating to listen and watch them even for just one morning!

Among the grasses and plantains

 

A juvenile grasshopper on the inflorescence of Plantago erecta.

A slightly different view, this time looking out from a grass blade:

 

Photographed on Bodega Head, 9 April 2014

Just four millimeters!

 

Eric and I continued our exploration of Bull Kelp holdfasts through March.  At the end of the month, we discovered this tiny sea anemone nestled deep inside one of the holdfasts.  It's hard to tell from the picture, but the anemone is only 4 mm across!

We're still looking at all of the characteristics, but at this time we're leaning towards calling this Aulactinia incubans.  If you've been following this blog, that species name might sound familiar.  We found a couple of adults last spring — see the post called "Mesmerizing" on 10 May 2013.

It's fascinating to think about this sea anemone, which broods its young in its tentacles, rafting along the shore in kelp holdfasts and drifting into new habitat. 

Here's one more view of this juvenile as it started to extend its tentacles.  The white stripes on the oral disc are just beginning to form.

 

P.S.  It seemed liked this would be an appropriate post for today — a 4 mm diameter anemone on 4/14/2014.

Appleseed and leopard skin?

On 27 November 2013, I showed a picture of one of my favorite marine snails, an Appleseed Erato (Hespererato vitellina).  To review, below is one of the images from that post:

 

What I didn't reveal at that time was that although I have found shells of this species, I had never found one alive...until now.

And this is one fancy snail!  Although "appleseed" is a good name for the shell, "leopard skin" might be a better description for the mantle, or the soft parts that extend up over the shell:

 

Here's a close-up of those spots and golden flecks that make your eyes widen.  It's hard not to say, "Wow!"

 

The snail's eyes look just like all of those black spots.  You can see one eye in the image below by following the lowest tentacle from its tip to its base — the eye is the first black spot you come to before you move up onto the rest of the body.

 

Besides black and gold, there were also quite a few orange spots.  They were especially noticeable on the snail's foot:

 

 

Appleseed Eratos are found in the low intertidal and subtidal zones along rocky shores.  Not much is known about their biology, but it's likely that they're associated with compound ascidians (sea squirts) — i.e., they probably live among them, eat them, and lay their eggs in them.  

While their dramatic spotted and flecked mantle stands out to us, especially against a black background, it probably serves as excellent camouflage when the snail is crawling over the surface of an ascidian.

Bodega Bay is the northern range limit for this species, so we're lucky that we get to enjoy this beautiful snail! 

 

P.S.  Appleseed Eratos are in the Triviidae family, sometimes referred to as "false cowries."  This name has been applied to them for a few reasons — not only are some of their shell characteristics similar to those of true cowries, but as you can see in these pictures, they also share an unusual ability to completely cover their shell with their mantle.

Orange and white with falcate tips

Not much time tonight, but here's an interesting moth that appeared at our house in Sebastopol a few nights ago. 

 

The orange coloration was really striking, especially in contrast to the white hindwings.

 

And note the falcate, or sickled-shaped, tips to the forewings.

 

I'm wondering if it could be a species of Drepanulatrix?

Hunting and grasping

I've had a couple of fun encounters with lizards recently.  

One young lizard hunting among the vegetation in the dunes: 

 

And a dramatic view of what I think is probably a male grasping a female with his mouth (see below).  After seeing this, I did a little research and read that males will do this prior to mating.

 

I think these are Northern Alligator Lizards (Elgaria coerulea), but I didn't get a close view of them, so I'm hesitant to say for sure.  [Interesting note: Northern Alligator Lizards will give birth to live young during the summer and early fall.]

Seeds in your socks

In late March, we noticed this object washed up on Salmon Creek Beach:

 

In took a few seconds for us to realize it was a sock! 

The sock was absolutely covered with marine life.  Here's a closer view (below).  It's easy to see that the dominant animals are hydroids (golden in color) and bryozoans (white and encrusting).  

When we were scanning to see what else was there, we were amazed to see a very high number of surfgrass seeds (Phyllospadix sp.).  Surfgrass is a flowering plant found in the low intertidal zone along outer coast rocky shores.  Almost all of the black structures on the sock are either entire or broken surfgrass seeds.  We counted at least 30 seeds on this sock!  

 

If you haven't seen a surfgrass seed before, you're in for a treat.  The following is a view under high magnification.  I didn't record the size at the time, but I'm guessing this seed was ~5 mm across.

 

Note the long barbs on either side with well-developed bristles.  These structures function to hook the seed on something like coralline algae, where the surfgrass seedling can then start to grow by putting down roots and sending up green shoots. 

This process was first illustrated by Robert Gibbs in 1902 (his research took place in Bodega Bay):

 

Modified from Gibbs, R.E. 1902. Phyllospadix as a Beach-Builder.  American Naturalist 36: 101-109.

Here's an example of what this looks like in the field (although it's better for the algae and the surfgrass if they don't wash up on the beach!).

 

I don't know if you noticed, but several of the surfgrass seeds on the sock had started to produce shoots!  In the picture below, look for the seed lying flat at the bottom of the image.  The green shoots are emerging from that seed.

 

Sadly, because this sock and seedling were washed up on the beach, this plant won't survive.  But here's what a nice bed of adult surfgrass plants looks like:

 

I'm sure many of you have experienced walking through grasslands during the summer and finding many grass seeds stuck in your socks...but until now, have you ever considered finding surfgrass seeds in a sock?  ;)

P.S.  If you're missing a sock, let me know.