Flotilla

  

We were in Monterey yesterday (5 June 2026) for a concert, but we drove down early to spend a little time along the coast.  Here's a nice seascape including a flotilla of sea otters in the kelp offshore from Pacific Grove.  [You can click on the photo for a larger version.]

Tool chest?

  

We had to do some field work in Monterey County yesterday, but we arrived a little early, so had a few minutes to observe a few sea otters while eating lunch in Pacific Grove.  

The first sea otters we saw were actively munching on sea urchins -- above, and next two photos:

 

 

 

But then our attention was drawn to a hard slapping sound, and we turned to see an otter trying to crack open a large mussel against a rock that was balanced on the otter's chest:

 

 

 

Several times we watched this otter dive down, bring up a rock and a mussel (or clump of mussels)...and then use the rock like an anvil -- hammering the mussel against the rock.

 

Sea otters are known to do this, but I hadn't photographed it before, so here are a few more images.  (Tool-use by mammals aside from humans is rare.)  In each picture, look for a rock resting on the otter's chest and a mussel between the otter's paws.
 

 

 

 

 

 

 

 

 

We were reading up on this behavior at the end of the day and came across an interesting research paper about tool use by sea otters just published in May 2024.

 

It turns out that using rocks as tools to access hard-shelled prey might be especially important for female otters in areas where their preferred and easier-to-process prey (e.g., abalone and urchins) aren't as common.  And using the rocks to open hard-shelled prey can prevent tooth damage and give the otters access to an alternative food source that otherwise wouldn't be available by biting alone.

Law et al. 2024. Tool use increases mechanical foraging success and tooth health in southern sea otters (Enhydra lutris nereis).  Science 384: 798-802.

 

Beechey on the beach

 

California Ground Squirrel (Otospermophilus beecheyi) on the beach in Pacific Grove in late July.

Little wonder

 

 

We've been working hard these past few days, but here's a quick shot of one of my favorite marine snails.  This is a pheasant snail, Eulithidium pulloides.  They're tiny!  Compare the shell to the sand grains in the photo.  I've posted about this species before, and I'm fascinated with the variable color patterns of their shells.  If you'd like to see some other designs, check out the post called "Six of a kind" from 21 August 2014.

A hint of purple

  

We're doing some low tide field work in the Monterey area.  During a short beach walk in Pacific Grove tonight (24 July 2021) we spotted this nice shell of a California Cone Snail (Californiconus californicus).  This species is not common in Bodega Bay, but see this post for a little more information: "Connections" from 19 September 2016.

At home in the sand

 

We noticed this small (~5 mm across) sea anemone in the low intertidal zone in Pacific Grove this weekend.  When I zoomed in on the photo on the camera, I realized it wasn't a species I was familiar with.  Later on, after doing a little research, I eventually figured out that this is Cactosoma arenaria — a new species of sea anemone for us!

There are a couple of things to notice about this speciecs.  As mentioned, it's small — typical height is only ~2 cm.  Look for the alternating brown and white bands on the tentacles (they generally have 24 tentacles).  Some of the bands are V-shaped (especially in the last photo of this post, below).  Also look for the brown cuticular sheath on the column (the lower portion of the anemone, see photo above).  The sheath includes embedded sand grains and shell fragments.

 

Cactosoma arenaria can be found around kelp holdfasts, and also among sand-encrusted tunicates (or sea squirts) in the low intertidal zone, which is where we observed these.  The species name, "arenaria", refers to sand.

 

This is a southern species, with known occurrences from about Monterey to San Pedro, CA.  So we're not likely to see it in Bodega Bay, but if you're in Central or Southern California, keep your eyes open for this little beauty.

Mmmm...kelp!

We were in Santa Cruz recently, and while we were there I remembered an encounter with a California Ground Squirrel (Otospermophilus beecheyi) in Pacific Grove several years ago.  I was intrigued to see the ground squirrel eating kelp — in this case, Feather Boa Kelp (Egregia menziesii).

I'm curious about how often mammals eat seaweeds.  Have you observed it before?

Here's a close-up of the ground squirrel:

 

Shell trio

Not much time tonight...we just got home from a class field trip to Monterey.  But here's a quick image from a beach in Pacific Grove today (10 March 2018), thanks to Eric's sharp eyes:

 

 

From the left to right: Red Abalone (Haliotis rufescens), California Trivia (Trivia californiana), California Cone Snail (Conus californicus)

Thinking of Rafe

 

 Pacific Grove, 7 April 2007 

 

Red Octopus (Octopus rubescens)

We're still in shock over the tragic loss of Rafe Sagarin.  Our hearts go out to his family.  Today we thought about places and things that Rafe loved and shared.  There is so much we'll miss about Rafe, especially his great kindness, creativity, and passion for natural history.

Six of a kind

This is one of my favorite marine snails, but they're small (usually less than 4 mm long), so they're often under-appreciated. They occur in Bodega Bay, but I found a few washed up on a beach in Pacific Grove yesterday, so I tried to photograph several of them.  

One of the most fascinating things about this species is the variable color pattern — although there are "themes," almost every shell you find is unique.

Meet Eulithidium pulloides (formerly Tricolia pulloides).  Here are six separate examples.

Sometimes the shells are relatively solid: 

 

Other individuals have large pale splotches:

 

Some have more swirled patterns: 

 

And others have bolts and zigzags of color:

 

Sometimes you have to look closely for the very fine stripes: 

 

Other times there are paisley-like prints: 

 

For comparison, here are all six of these individuals together.  Note the sand grains in the picture.  The largest of these snails was 3 mm long.

 

The Light and Smith Manual (2007) says that Eulithidium pulloides is found "in gravel, under rocks, or associated with surfgrass or algae."  I also located one reference that noted their occurrence with subtidal coralline algae.

I wish I knew more about this species, especially the reason for such variable shell patterns!