Tricolored!

  

We were out in the field briefly this past weekend and I encountered two different hermit crabs in these beautiful snail shells — Three-colored Top Snail (Calliostoma tricolor).  

The snail is generally a more southern species, with most range descriptions describing their distribution from Santa Cruz south to Baja California, Mexico.  Looking online, however, there are quite a few records north of Santa Cruz to at least Bolinas, and one outlier up in Mendocino County (Thanks, Michael!).  So for the record, here's an observation from Sonoma County on 26 January 2024.

Splish, splash!

  

Today's rain filled our bird bath...and then a flock of Bushtits (Psaltriparus minimus) came by and enjoyed a bath.  Bushtits seem to do everything together, so there was lots of splashing!  

Most of the time, foraging Bushtit flocks move through our yard fairly quickly, so it was nice to see them pause, if only for a minute, and enjoying the rain.

 

Focused

  

Wow!  This weekend, Eric looked out the back door and noticed this adult Cooper's Hawk (Accipiter cooperii) sitting on a post in the garden.

The hawk spent quite a bit of time hunting...landing on tomato cages and walking among the plants.  We're assuming it was focused on finding a songbird.  Impressive to see it up close and to watch its behavior!

Here's another view:

 

 

This Cooper's Hawk is on the smaller side, so likely a male.  [You can click on the images for larger versions.]

Ready to settle down

  

Okay, back to these little snails that I posted on 27 January 2024!

This would have been a challenging one to identify unless you've spent some time looking at vermetid gastropods, or tube snails.  These are newly hatched Petaloconchus montereyensis!

And if you haven't heard of tube snails — yes, that's right, these are snails that don't crawl (at least as adults) and instead live in a calcareous tube that's cemented in place.  

This species of tube snail is a brooder — the adults lay egg capsules inside their tubes and the juveniles hatch and crawl away.  They only crawl for a brief time before attaching to the substrate — e.g., a rock surface or the tube of an adult.  (They tend to be gregarious.)

One of these snails settled after only two days.  In the video below you can see the tiny juvenile (only ~2 mm across) with the new tube that it produced.  And if you look very carefully you can see the coiled shell that it started out with at the very base of the tube!  So cool!  

As adults these snails are attached to the substrate, so they feed in a different way than many common marine snails.  Instead of grazing on algae on the rocks or in tidepools, Petaloconchus feeds by casting a mucous net into the water, letting organic material get caught in the net, then pulling the net back into its mouth.  The snail uses its radula (like a tongue with rows of sharp teeth) to retrieve the net.  Eric captured some video of that feeding motion, too, so he included it in this clip.  This is pretty spectacular footage of tube snails, so be sure to check it out!

The video sequence goes something like this:

• First 20 seconds — juveniles crawling on their own
• At ~22 seconds — juveniles exploring the outside of adult tube snails
  
• At ~48 seconds — close-ups of the newly settled juvenile with a coiled tube!
• At ~1:05 minutes — miscellaneous shots of adult tube snails with nice views of their radulas in action
  

Thanks for the terrific video, Eric!

Warming up

   

If you're interested in the identity of the snail I posted about last night, I'm going to delay the answer by one day — mostly because there might be more footage we can share, but it's not quite ready yet.  For now, I hope you enjoy this beautiful Mourning Cloak (Nymphalis antiopa)!

Air temperatures reached 68°F on Cotati today (and I heard that Santa Rosa reached 72°F, tying a record for the date).  Around mid-day Eric spotted a Mourning Cloak in our backyard, but it flew off before I could take a photo.  So I went for a short walk down the street to a spot where I thought it would possible to see another one, and sure enough there were two Mourning Cloaks there sunning in a wet wooded area.

This is one of my favorite butterflies, but I don't see them that often.  I love the deep mahogany color above and the beautiful gold and blue combination along the wing margins.  And they look completely different when the wings are closed, more like a dark leaf or piece of bark:

 

 

Perhaps you also observed indicators of the warm air temperatures today?

A short walk

  

Pretty cute, huh?  Eric filmed these two juvenile marine snails tonight.  They're only ~1 mm long.  He put together a nice video clip of them, too — see below.  [If you're reading this in an e-mail, click on the title of the post to see the video on the NHBH website.]

These snails are a little unusual in that they look quite different in this stage vs. how they look as adults.  

We thought we'd post the footage first to let you explore and wonder about which species this might be.  Any guesses?  I'll share more info about them tomorrow!

First of the year

  

Full moon photographed in the early morning on 25 January 2024.