Celebrate the oceans

 

On World Oceans Day, there are so many reasons to celebrate.  Because this is a natural history blog, I'll mention two reasons related to that topic.  Tonight I'm choosing endless beauty and wonder.  

I'll always be thankful for the wonders of marine life.  I can't imagine ever visiting the ocean without being stirred to ask questions or being presented with a mystery to try to solve.   

And I couldn't be more grateful for the beauty of seascapes.  The oceans provide so many inspirations to carry with us — whether it's a seabird soaring over open ocean waves, colorful invertebrates and seaweeds in tidepools and on beaches, or storms and big surf crashing against the coast.  I'm so thankful for the oceans' gifts!

Singing redstart

A few people have expressed interest in seeing and hearing this American Redstart (Setophaga ruticilla) that appeared on Bodega Head today (7 June 2016).

This isn't a great photo, but it's the best I have under challenging conditions.  You can see the orange patches along the sides and dark gray-black splotches on the face and breast indicating a young male.

 

I managed a couple of song recordings for the record.  Below are two examples.  [If you can't see the audio files in your e-mail, click on the title of the post above to go to the web page.]

Rings around the boulders

We were on our way to do field work in the rocky intertidal zone early this morning, when we noticed this:

 

Can you see the orange coloration along the lower part of the wall and forming rings around the boulders?

Here's a closer view (below).  The boulder is about 2.5 feet across (~76 cm).  Any guess about what's causing the orange color?

 

There are orange sponges in this area that could look like this from a distance, but it didn't seem quite right, so we got down for an even closer view:

 

Spirorbid tubeworms!  Wow, neither of us had seen such dense and expansive aggregations before.  

The next photo is helpful because some of the tubeworms are underwater with their bright orange tentacles expanded, and others are out of the water with their tentacles withdrawn so it's easier to see their white tubes (with just a hint of orange at the entrance).

 

Most spirorbid tubeworms are brooders (brooding their larvae) and once released their larvae have very short planktonic durations — swimming in the water column for a very short time before they settle onto a rock (or other suitable surface).  

Perhaps the surge channel we walked by is a good setting for high retention, where many larvae are released and then settle in close proximity to each other instead of being swept away by waves and currents?

If you're interested in seeing microscope views of these fascinating tubeworms, review the post from 6 February 2012.

A greenish glow

 

It's always exciting to see an octopus.  Eric spotted this one this morning (5 June 2016).  It was in a low tidepool with lots of surfgrass (Phyllospadix sp.).  Perhaps the octopus was matching the greenish background of the surfgrass?  

The green coloration was beautiful.  Below is a closeup of the eye and surrounding skin.

 

Recently, a number of octopus like this one (Octopus rubescens) have been observed in local tidepools.  Perhaps it will be a good year for octopus?

P.S.  This is a bit of a prelude to World Oceans Day on June 8th.  How will you celebrate the oceans?

June Gloom?

 

June Gloom?  I kind of like it.  Fog photographed off Bodega Head on 3 June 2016.

Harbinger?

Just a quick note...

 

Most of the By-the-wind Sailors (Velella velella) we've seen this year have been small (under ~2 cm long).  Today I photographed the largest so far in 2016 at ~6 cm long (above).  Is it a harbinger of things to come?  If the winds shift to the west next week, it'll be interesting to see if larger By-the-wind Sailors are observed washing ashore.

Streaming

Perhaps you've seen this seaweed, either growing on intertidal rocks, or washed up on the beach?

 

Meet Halosaccion glandiforme.  This seaweed is a bit like a water balloon — an inflated oblong sac partially filled with water. 

Halosaccion is streamlined and flexible — designed to withstand currents and waves.  It also has tiny pores near the rounded, distal end (away from where it attaches to the rock).  The tiny pores allow water to flow into the sac when the algae is submerged under water.  Then when exposed to air during low tide, the water inside the sac helps prevents desiccation (drying out), and might also play a role in maintaining a lower temperature.

If you find Halosaccion washed ashore, you can see evidence of the pores for yourself.  Compress one of the sacs between your thumb and finger, and watch powerful jets of water stream out:

 

Some of the information above is from the following paper: Vogel, S. and C. Loudin.  1985.  Fluid mechanics of the thallus of the intertidal red alga, Halosaccion glandiforme.  Biological Bulletin 168: 161-174.