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 Coast Garter Snake (Thamnophis elegans terrestris), 30 June 2019

Morning silk

I wandered into the backyard again this morning to look for spider web strands.  Below are a few close-ups from 29 June 2019.

Strand with satellite:

 

A colorful intersection:

 

Most of the time when I photograph spider web silk, the color order seems random.  However, this morning I captured one strand with colors that were very close to being in "rainbow order" — that is, the colors were almost displayed in the same order you'd expect in a rainbow (starting from the right and running to the left) = red, orange, yellow, green, blue, violet: 

 

Into the sunset

 

Sunset from Cotati, 27 June 2019

 

Too hot -- Part 3

 

Remember the mussel mortality event that I mentioned last week?  (See posts called "Too hot" and "Too hot -- Part 2")  

Eric Simons wrote an informative article about this event for Bay Nature magazine.  You can read the article online here.

The photo above was taken on 18 June 2019 and the photo below was taken on 19 June 2019.  

In the first photo you'll notice that some mussels are empty, but others still have their adductor muscles — the white muscle that holds the two shells together.  In the photo below, the majority of mussels are empty, but in a few you can see the orange internal tissue (before it washed away or was eaten by other animals).  At low tide, healthy mussels are normally closed up tightly, so you can't see the internal tissue or the inside of the shells.

 

 

Resting among the rocks

 

Recently I was checking on some Black Oystercatchers to see if they might be nesting this year.  

Can you spot the small oystercatcher chick in the photo above?

The chick looks just like the surrounding rock, so check carefully.

If you need some help, I've circled the chick in the image below.  It has a short, dark bill and its head is facing left.

 

P.S.  I took this photo with a large lens from far away so as not to disturb the birds.  The original image has been heavily cropped.

Foam studies

 

Interesting patterns in the foam near shore yesterday, 23 June 2019

 

 

Summertime rays

 

A beautiful sculpin in a shallow pool near Pinnacle Gulch, Bodega Bay, 22 June 2019.  [You can click on the image for a larger version.]

Spending the summer?

Mid-June is probably one of the least likely times to see a Whimbrel (Numenius phaeopus) in Bodega Bay.  Most of them are much farther north at this time, nesting in the Arctic.

When you see a Whimbrel in mid-late June, it's probably either a non-breeding individual that didn't migrate north, or one that's returning from the breeding grounds very early.  I'm guessing this is the former, as its feathers are very worn and tattered, as if it didn't complete a molt into breeding plumage.

Photographed in Bodega Bay on 22 June 2019.

 

A light celebration

If you've been reading this blog for the last few years, you might remember previous posts about color patterns in spider web silk.  Since it was the solstice today, I was thinking about light.  So I went out quickly before work to see if I could find a nice spider web strand.  I'm a little out-of-practice, but here are a few examples to help celebrate the summer season.  Pick your favorite!

 

 

 

 

P.S.  Here are links to some past examples:

Celebration of light -- 20 June 2017

Silk Road to Enlightenment -- 22 June 2017

 

Spiderworks -- 3 July 2017

Early evening light -- 5 July 2017

Color combinations -- 9 July 2017

Game of threads -- 17 July 2017

Shifting sun -- 31 July 2017

 

The thread continues -- 13 August 2017

Bands of light -- 14 August 2017

Solstice, silk, and light -- 21 June 2018

 

Question: "Are jellyfish edible?"

 Answer: "Why, yes!" replied the sea anemone.

 

 

This Giant Green Anemone (Anthopleura xanthogrammica) appeared to be ingesting a Pacific Sea Nettle (Chrysaora fuscescens).  Photographed on 20 June 2019.

P.S.  Happy Summer Solstice!

Too hot -- Part 2

For the record, I'm sharing a few more photos of the California Mussel mortality event in the intertidal zone that I mentioned last night.  We think this is the most significant mussel mortality we've seen on Bodega Head during the last 15 years (in terms of number of individuals and the amount of area impacted).

In these patches (photographed on 19 June 2019) you can see that most of the mussels in the top layer of the mussel bed have died.  The light blue color is the inside of the dead, gaping shells.  

Although it's hard to estimate percent mortality throughout the entire mussel bed, many areas across the intertidal zone look like this right now, with some shells gaping wider than others.

 

 

Too hot

Last week's record warm air temperatures (for the date) seem to have impacted some of the local rocky intertidal zone species.  Unfortunately, the high air temperatures coincided with midday low tides.  Sometimes it takes a little while for the effects to show up.  

While doing field work this morning (18 June 2019), we observed quite a bit of bleached algae in the mid-to-high zone (see below).  These seaweeds are usually darker green and brown — the whites and reds are abnormal for these species.  [In this photo, much of the white algae in the foreground is Mazzaella sp., while the reddish looking species is Dwarf Rockweed (Pelvetiopsis limitata).]

 

There has also been a significant die-off of California Mussels (Mytilus californianus).  A large percentage of the mussels were open and gaping, some were empty and some still had tissue inside.  Here's one example:

 

We're curious about how widespread this mussel die-off was.  If you see large patches of open, gaping, dead mussels in the intertidal zone and you'd be willing to share a photo, I'd be interested in hearing about your observations.

Indigo blue

 

As you can see, I'm still reviewing some photos from field work in northern California and Oregon earlier this month.  This is an example of a Leather Star (Dermasterias imbricata) with very dark coloration.  Usually we encounter individuals with paler gray in the background, but this one featured beautiful indigo blue.

Oregon eye

Well, I'm still having some computer issues (and some catching-up issues), but here's a nice fish from our Oregon trip.  About a week ago, I posted a sculpin that looks quite similar to this individual, but that was from a local site.  This one (below) is from Cape Arago, and it's a much better view of the beautiful eye coloration:

Erosion as art

 

 

Rock formation at Cape Arago, Oregon.  I couldn't decide which view I liked better, so here's a horizontal image (below) so you can choose!

 

Dolphin days of summer?

It was another hot day, so we decided to linger at the coast after work to try to avoid some of the higher temperatures inland.  With a little extra time, I decided it might be a good evening for dolphin spotting.  The ocean has been flat calm recently — good conditions for spotting dolphins near shore.

Bottlenose Dolphins (Tursiops truncatus) aren't easy to predict in the Bodega Bay area, and I wasn't certain I'd find any, so I was a little surprised to spot one right away.

The dolphins were a little distant, and they weren't spending a lot of time at the surface, but here are few pictures for the record.  I'm guessing there were at least three different individuals.

This appeared to be an adult (left) and calf (right):

 

Pretty smooth dorsal fin, but noticeable scratches in front of the fin:

 

 

Notched dorsal fin (I'm wondering if Bill will be able to i.d. this individual?):

 

And two shots of dolphins surfacing.  Sure seemed like a good time to be a dolphin!

 

 

P.S. I'll check in with Bill Keener (Cetacean Field Research Program at The Marine Mammal Center) to see if he has any thoughts about the identification of these individuals. 

P.P.S.  I realize the title of this post isn't quite accurate — the "dog days" of summer don't begin until July 3rd, but I couldn't resist the title, especially given the heatwave we've been experiencing.  Stay cool!

Scorcher

 

Whew.  There were record high daily temperatures throughout the Bay Area today.  I heard that air temperatures reached over 100°F in inland locations.  Even on the coast, temperatures reached ~77°F (25°C) — very warm for Bodega Bay, especially at this time of year.  Let's hope for some cooling soon!  Sunset photo from Cotati on 10 June 2019.

Cooling off at the coast

I've been having some computer issues (sigh), but here are a few photos from a visit to some sandy tidepools in Marin County today (9 June 2019).  It was cooler at the coast this afternoon, but it's still over 80°F (26°C) in Cotati tonight (after 8 p.m.).

 

 

 

I'm not sure about the identification of the sculpins, so if you have any thoughts about them, let me know.  The anemone is a Moonglow Anemone (Anthopleura artemisia).  They're often found at sandy (or gravelly) sites.

Gold with black spots

 

Aldisa cooperi, a wonderful nudibranch at Cape Arago, Oregon, on 5 June 2019

Little green marbles

 

I encountered a small patch of Derbesia marina after field work in Oregon this morning — a fun seaweed sometimes called Green Sea Grape.  It looks like little green marbles (or miniature glass fishing floats?).  [Each "bubble" is less than 10 mm across.]

Here are two more views:

 

 

Derbesia marina is often found fairly low in the intertidal zone emerging from coralline algae (the encrusting pink algae in the background).

I haven't seen Derbesia on Bodega Head that often, but here's one example from 2010:

 

Coastal patterns

 

Wandering Tattler (Tringa incana) near Newport, Oregon, on 4 June 2019.

Also nearby were these amazing Gooseneck Barnacles (Pollicipes polymerus).  They were noticeably large individuals!

 

One more photo — a close-up of the Gooseneck Barnacles highlighting the wonderful patterns created by their plates:

 

High tide roost

 

Pigeon Guillemots (Cepphus columba), Oregon coast, 3 June 2019

ADDENDUM (4 June 2019): Alice mentioned the red feet and red mouth lining of guillemots.  They aren't visible in the roosting birds (shown above), but here's a mating pair that highlights the red feet:

 

A farewell to arms

We were at a rocky intertidal zone site in northern California this morning and started noticing Six-armed Sea Stars (Leptasterias sp.) with fewer than six arms.  Here's one with three arms:

 

We also observed many Six-armed Sea Stars that were regrowing lost arms.  Below is an example of a "comet"— an individual that has one remaining original arm (the longest), with the rest of the arms regenerating:

 

We were curious about the cause of arm loss, when Eric discovered some possible evidence:

 

This Six-armed Sea Star was being ingested by another sea star.  

And the responsible sea star was...

 

...a Leather Star (Dermasterias imbricata)! 

We found at least three examples of Leather Stars eating Six-armed Sea Stars.  In one case, the Six-armed Sea Star had been completely digested.  But in two cases, some of the Six-armed Sea Star's arms had yet to be ingested.  We're wondering if it's possible that sometimes enough of the Six-armed Sea Star survives the predation attempt and escapes to regrow the arms it has lost.

If you're not familiar with Leather Stars, here's a photo from above:

 

Although it doesn't sound like this is the first time Leather Stars have been observed eating Six-armed Sea Stars, we're not sure how common it is.  (Leather Stars often eat sea anemones as well as a variety of other prey.)