Feeding the young, part two.

As there will be an unknown number of feeding the young posts I decided to number them rather than trying to come up with different titles for each one.

In this photo one of the adults is feeding a green caterpillar to the young.

Here the young are a few days old. I can now see 9 young, there will be more.

Feeding the young.

Land, mate, preen.

A sequence of photos taken on the Lake Huron shoreline in the spring.

I was photographing a Common Tern on a rock in the water when a second bird flew in.

Two Common Terns

The second bird landed and approached the one on the rock. By the front birds wing position it was fairly obvious what was going to happen next.

Ready to mate.

The birds mate. I’m guessing that they were a well established pair as the male didn’t bring a fish as a courtship offering.

mating Common Terns

After mating both birds started preening.

Preening Common Terns

Polarized light photomicroscopy.

In the early 1980s I was running the photo department at a scientific research establishment. This involved a wide variety photo techniques to record a range of subjects.

However, polarized light photomicroscopy wasn’t used for anything work related. Having seen the results of other people I decided to investigate the technique. In those days that meant researching in literature rather than simply Googling as you would these days.

Now I will admit that I am writing this from memory, I have googled the subject and what I have found matches my memories of the technique.

I applied drops of a Sodium Thiosulfate solution to some microscope slides and left the solution to evaporate so that crystals would form.

I mounted a polarizing filter between the light source of the microscope and the slide stage. Once the Sodium Thiosulfate had crystallized I put one of the microscope slides on the stage and put a second polarizing filter above the slide. When you rotated one of the polarizing filters the colour of the crystals changed.

The first photo shows what I found to be a fairly typical example of the crystals.

polarized light microscopy

This photo shows small patches of colour against a mostly dark background. I’m guessing that this is a result of the orientation of the polarizing filters.

polarized light microscopy