Blondie

  

During a field trip to Tomales Bay on 17 August 2023, Melissa spotted this small yellowish-green sea hare crawling on some eelgrass (Zostera marina).  At first I wasn't sure about the identity of this sea hare, but after looking more closely I believe it's a Hedgpeth's Sea Hare (Elysia hedgpethi).  (Those small bright blue spots helped with the i.d.)

I've mostly encountered this species on rocky shores where they are a deep green color (see "Not a flatworm!" on 25 June 2013 and "Magic cape" on 17 August 2022).  So the paler "blonde" color was confusing until I read that this species can be yellowish or brownish, too.  Is the color driven by what they are eating?  Or related to the condition of the chloroplasts they ingest?

Eric was able to get a few nice video clips, too, so check out the video below.  Watch for the rolled rhinophores, the two dark eye spots behind the rhinophores, the wide flaps held upright on either side of the body, and the scattered blue spots.  [If you can't see the video player in your e-mail, click on the title of the post above to watch the video on the NHBH website.]

Many thanks to Melissa for spotting this sea hare and to Eric for putting together the video!

Calming effect

  

The wind picked up this afternoon (9 June 2021), but it remained calm among the Eelgrass (Zostera marina) in Bodega Harbor.

Summer fog and a breeze

 

Thought it would be fun to share a few shots from a recent sail in Tomales Bay.  Above, approaching White Gulch on Tomales Point.

Eelgrass (Zostera marina) meadow in the foreground:

 

Tomales Point shoreline through the fog:

 

The final run before we headed back to Nick's Cove:

 

Among the seagrass and kelp

 

Yesterday (16 August 2019) I noticed a few Red-necked Phalaropes (Phalaropus lobatus) feeding among the rafts of seagrass and kelp near shore, so here are a couple more photos.

 

Clinging to an eelgrass blade near you

Katie had been seeing these small hydromedusae among the eelgrass (Zostera marina) in Bodega Harbor.  We finally looked at some under the microscope together and believe we identified them as Cladonema californicum. 

There are some amazing things about this species and it has some fun connections to wonderful people and local places, too.

Cladonema californicum was first described by Libbie Hyman in 1947.  To describe the species, she used organisms sent to her that were collected in Tomales Bay (near Dillon Beach) by Frank Pitelka in 1941.

Here are two figures modified from Hyman's paper.  The first shows the most obvious features (that you can identify in the next photo!) and the second highlights the unusual branched tentacles — one branch that ends in a sucker and the other with stinging branches.   

  

Both figures modified from Hyman, L. H.  1947.  Two new hydromedusae from the California Coast.  Trans. Am. Microsc. Soc.  66: 262-268.

Now here's a close-up photo of the living hydromedusae.  Look for all of the parts mentioned above.

 

Can you see how the hydromedusa is using the tentacle branches with suckers to cling to the eelgrass blade?  Many of you are probably used to seeing hydromedusae swimming through the water column (like jellyfish).  This species is unusual in that it has adopted a partially benthic lifestyle.  It holds onto the substrate with adhesive pads and then spreads its stinging tentacles to capture prey (e.g., small crustaceans such as copepods).

The next image highlights the fascinating suckers.  The hydromedusa was crawling to the other side of the eelgrass blade when I took this picture.

 

While watching the hydromedusa, we also observed an interesting behavior.  Occasionally it would draw its stinging tentacles and sucker tentacles into the bell and drag them past the oral tentacles (see next photo). This looked like feeding behavior (like wiping your fingers across your lips), although I'll admit that we didn't actually see the hydromedusa catch any prey and I'd feel more comfortable with more observations to say for sure.

P.S.  Libbie Hyman was one of the most influential invertebrate zoologists in North America.  She single-handedly wrote a six-volume treatise called The Invertebrates between 1940 and 1967.  The format of these books was later adopted by other invertebrate textbooks in use today, and her volumes are still consulted and admired for their depth and comprehensiveness.

Here's a nice photo of Libbie Hyman from the American Museum of Natural History's publication about her:

 

From Libbie Henrietta Hyman: life and contributions.  American Museum Novitates no. 3277 (published in 1999, edited by Judith Winston).

What do coots eat?

Sometimes an observation reminds me how easy it is not to ask questions about what's around us.  I've seen American Coots (Fulica americana) frequently in Bodega Harbor, but I hadn't stopped to wonder what they might be eating.  

On 28 January I was watching shorebirds through a spotting scope and heard some unusual sounds — splashing, chuckling, slurping.  I looked up to see a large group of coots in a nearby tidal channel.  I took the photos below to try to see what they were eating (click on the pictures to see larger versions):

 

 

 

The first photo shows bright green pieces of sea lettuce (Ulva sp.) in their bills.  The coots then moved further upstream into a deeper part of the channel.  They became very active, leaping out of the water and diving beneath the surface (second photo).  When they emerged they had long green ribbons of eelgrass (Zostera marina) in their bills (third photo).

I don't know what else coots might be eating in this area (do you?), but these photos document at least two species that make up a portion of their diet on Bodega Head.