Basking and nectaring

   

Air temperatures reached at least the high 60s in Bodega Bay today (7 March 2026).  I started seeing butterflies zipping by in the morning, so I went out after lunch for a short walk and took a few photos.

California Tortoiseshells (Nymphalis californica) were the most common butterflies I saw today (photo above), but I also noticed quite a few Margined Whites (Pieris marginalis) and at least one Western Pine Elfin (Incisalia eryphon).

Many of the tortoiseshells were nectaring on willow catkins:

 

 

Warm enough for tortoises

  

Wow, hard to believe, but air temperatures reached ~75°F (~24°C) on Bodega Head today.  And yesterday they were only ~5° lower than that.  

There have been lots of California Tortoiseshells (Nymphalis californica) flying by.  Here's one on Claytonia perfoliata.  It was probing the surface of the leaf with its proboscis, but I'm not sure if it was after moisture or salt?

Sunshine corner

  

Air temperatures reached daily record highs today (23 February 2021).  It was in the high 70s and perhaps the low 80s in Cotati this afternoon.  With warmth like that, it's not surprising a few butterflies were out basking in the sun.  Late in the day we found one little sunny corner in our neighborhood with a handful of butterflies — a mixed "flock" of California Tortoiseshells (Nymphalis californica), shown above, and West Coast Ladies (Vanessa annabella).

Fall flights

I know I promised more pictures from the pelagic trip, but there was also an interesting flight of butterflies today that I thought was worth documenting.  So, here's a bit of both.

First, from the pelagic trip.  Here are two views of arcing shearwaters on the horizon taken from the boat on our way back from Cordell Bank on 22 September 2019.  The winds had picked up (probably ~15-20 knots), creating conditions when seabirds are often soaring high above the ocean surface:

 

 

Second, the butterflies.  During the fall, when inland air temperatures are very high, we can see flights of butterflies at the coast.  Today there were quite a few California Tortoiseshells (Nymphalis californica) coming in off the ocean and crossing over Bodega Head.  Most of them rocketed by, but occasionally they landed briefly, either on the ground or on the outer walls of buildings:

 

 

Flights of shearwaters and tortoiseshells — a nice combination!

Fall colors

The large-scale movement of California Tortoiseshells (Nymphalis californica) that I mentioned in last night's post continued this morning.  The butterflies seemed to be enjoying the morning sun on the south-facing walls of the Bodega Marine Laboratory.

Many of them were also probing the surface of the building with their proboscises.  I wondered what they might be interested in — could there be salt on the outside of the building?  Or were they just searching for moisture or nutrients?

They're such beautiful butterflies, and I just love the fall colors in their wings.  I took a few photos for the record:

 

 

 

 

Why did the tortoiseshell cross the road?

Late this afternoon, I was driving south along Highway 1 from Bodega Bay towards Valley Ford, when I noticed a fairly steady stream of butterflies crossing the road.  I thought they might be tortoiseshells, but I wasn't certain without a better view.  So I pulled over in Valley Ford to take a closer look.

The number of butterflies was impressive!  I counted more than 50 individuals in ~10-15 minutes.

They were California Tortoiseshells (Nymphalis californica), and here are two photos for the record.  Both were taken on the outer wall of what is now the Northern Light Surf Shop in Valley Ford.

 

 

Around this time last year, there was also a large movement of California Tortoiseshells.  See the post called "And the answer is..." on 26 September 2017.

 

Warming up

Remarkably, air temperatures reached 70°F (21°C) in Bodega Bay this afternoon.  That's warm for February!  [Daily air temperature records were broken throughout the Bay area today.]

I decided to go for a short walk in the late afternoon to look for butterflies basking in the sun.

I wasn't surprised, but it was interesting to see five species of butterflies today.  I'll show all five below so you can compare them.  (Note: All five species can overwinter as adults in this area, hence their brief appearances on warm days.  In contrast, many other butterfly species overwinter as caterpillars or pupae.)

 

Monarch (Danaus plexippus) 

 

West Coast Lady (Vanessa annabella) 

Satyr Anglewing (Polygonia satyrus)

 

California Tortoiseshell (Nymphalis californica) 

 

Red Admiral (Vanessa atalanta)

 

And the answer is...

Tortoiseshells!

Last night I mentioned butterflies zipping by, and that I wasn't sure if they were Satyr Anglewings (Polygonia satyrus) or California Tortoiseshells (Nymphalis californica).  There were even more butterflies today, and I finally got a few photos.

The first photo was one for documentation, but I like it because the butterfly was perched on a seine net:

 

Then I managed to get a few more photos — here's one from above:

 

Compared to Satyr Anglewings (see last night's post), note that California Tortoiseshells have fewer dark spots on the hind wings, pretty blue spots along the trailing edge, and relatively smoother wing margins (anglewing is an appropriate name for the other species).

Here's the view from below.  I love the coppery tones and the bark-like appearance:

 

You can see how well camouflaged California Tortoiseshells are against background vegetation when their wings are closed:

 

So this is the first time I've seen California Tortoiseshells on Bodega Head.  It was so much fun to see them flying in off the water (most were flying west to east), and to wonder where they were coming from and where they were going!  This species is known to undertake long-distance movements, so it's not necessarily surprising to see large numbers of tortoiseshells flying by.  However, in my experience here during the last 12 years, it's uncommon (rare?) to see this species, and large movements of this species, along the coast.  (Large movements are more common in the mountains.)

I'd love to hear about other tortoiseshell sightings in this area, so let me know if you see them!