Following the birds

If you grow up fishing, with an eye on the birds to show you where the fish are, will there always be something inside of you watching out of the corner of your eye for bird activity?  

I grew up lobstering on the East Coast, but if there were a lot of birds feeding nearby, sometimes my dad would let us follow the birds and go fishing for stripers or bluefish for the day instead.

On 21 June, a flock of Western Gulls caught my eye.  And I couldn't help wondering what they were being drawn to. They were finding something on the beach.

 

Curiosity got the best of me and I went down to see if I could find out what they were eating.  This is what I discovered in the wrack line (next image).  Can you tell what they are?

 

It turns out that the gulls were after krill.  I collected a few and took some quick photos under the microscope for the record.  (The third image is a close-up of the eye.)

 

 

 

You may recall that I photographed ravens eating krill on the beach in March (review that post here).  It looks like this is a different species of krill.

Later in the day we went back to see if the gulls and krill were still there.  Sure enough, the gulls were still picking through the seaweed looking for krill.  The Western Gulls had now been joined by a few Heermann's Gulls (see below).  

 

Many of the krill that had washed ashore earlier in the day were now dried, but the gulls still seemed interested.

 

If you follow the birds, you never know what you'll find!

A delicate touch

Today I was watching a pair of ravens foraging on Salmon Creek Beach.  They were delicately picking along the drift line left behind by the receding waves.

 

The ravens were very focused and were spending a lot of time searching for and apparently finding quite a few small food items.  

 

 

At first I thought they might be eating beachhoppers.  But their method of feeding didn't match the abundance or behavior of beachhoppers.  They seemed to be picking up prey quite regularly and in a narrow search area.  If they had been feeding on beachhoppers, I would have expected them to find fewer and to be more sporadic and random in how they caught them.

Also, the ravens would lean down and pick up the food from the surface of the sand with the very tip of the bill (see next images). 

 

  

Unfortunately, even with binoculars, I couldn't see what they were finding.  But eventually I had been watching long enough that I was really wondering what could be so interesting to the ravens.  So I walked up to a similar tide height, knelt down, and started looking at the sand.  Here's what I saw:

 

Can you see the small pinkish shrimp-like animals?  It's the best I could do in the field, as most of these animals were very small (less than 1 cm long).  Below is another example.  Note also the very large dark eyes.

 

I didn't have much time, but decided to bring a few back to look at them under the microscope.  This is the animal that the ravens were spending so much time looking for and eating on the beach:

 

I'm not an expert, but I'm pretty sure this is a type of euphausiid, or krill.  The ravens were feeding on krill!  [I know there are other people out there who have a lot more experience with these crustaceans, so if you can identify the species (or genus), or tell us anything more about them, please do.]

Here's one more picture of a different individual:

 

And I can't resist showing a close-up of the compound eye.  Although I've known about krill for a long time, I've never looked at their eyes under a microscope until today.  Beautiful!

 

I'm so thankful to the ravens for leading me to the krill on the beach.  It's made me realize that there's a lot I don't know about krill in this area, so I have some research to do.  And who knew that ravens ate krill!