All My Blogs

Main:  A blow fly feeding on a dead Steller's jay chick.  Inset:  Maggot showing a pair of mouth hooks. Blow flies - if you watch forensic shows like Bones , you are probably familiar with the idea that the flies' larvae are used to help determine how long someone has been dead for.  The TOD (time of death) is determined in days, not hours, as the corpse has to be old enough that blow flies would find the body, lay eggs on it, and the maggots would hatch, grow, and moult.  The time between moults is an instar; each instar (3 in all) takes a certain length of time, with growth occurring along the way.  You can tell how long a body has been in place by the presence of blow fly maggots and how big they are. However, it is a bit more difficult than that.  There are different varieties of blow fly, each of them reproduces at specific rates relative to that species.  Another factor is the temperature associated with the body.  Flies develop more sl...

Four different insects that are important detritivores. What's a detritivore?  An organism that feeds on dead matter, plant or animal.  There is a long list of detritivores, including most fungi, bacteria, and a plethora of invertebrates.  I came across a dead Steller's jay chick a few weeks ago and discovered quite a population of scavenging insects.   Nothing in nature goes to waste.  Every atom in every living thing has been used before, again and again and again.  Plants extract nutrients from air, water, and soil.  Animals eat plants and other animals.  And all of them, when they die and their remains are left to the elements, are consumed by detritivores. Every.     Last.    Atom. The food web wouldn't be complete without detritivores.  Nutrients would make a one-way trip and not return to the environment.  Even fecal and metabolic waste is recycled.  Although we may feel gross or get a bad case o...

Does the bright yellow colour of goldfinch males make them easier prey for predators? The phrase "Sticking out like a sore thumb" could be applied to male goldfinches.  Not only are they a bright dandelion yellow, but they have dark, black contrasting feathers that make them stand out even more.  What evolutionary pressures would shape such a creature? Birds of prey and predatory mammals such as cats have colour vision and sharp eyes that pick up not only the colour of the male goldfinch birds but their strong contrast too.  Female goldfinches (see below) have more subdued yellows, less black, and do not have a stark black cap.  Of the two birds, the male is more likely to be seen and hunted.  This gives the female a better chance at incubating the eggs and rearing the young. Male (left) and female (right) American goldfinches. The bright yellow of the male also acts as a signal to females of his fitness for breeding.  The bright yellow colour comes from pi...

 Left:  Western conifer seed bug on the siding of my house in Kelowna. Right:  Box elder bug. The western conifer seed bug is a member of the leaf-footed bugs. Leaf-footed bugs can be identified by the widened tibia seen on their hind legs.  It is common to find them around your home in the fall as they will gather by the hundreds looking for a warm place to overwinter.  Another insect that you may find with a similar MO is the box elder bug.   Western conifer seed bugs are mild pests to Douglas fir trees, although they may also feed on other conifers such as pine, hemlock, and spruce.  They do not eat cedars.  The bugs are specifically interested in the young cones and their developing seeds, although they will also feed on the needles and flowers of conifer trees.   I commonly find both species of insects at home.  They start to arrive in the fall.  It is not uncommon to find several of them each day scampering about the...

Top:  Common goldeneye ducks.        Bottom:  Barrow's goldeneye ducks. I have taken the above images from photos I have shot over the years, some taken this year (the female common goldeneye) and some taken years ago (the male common goldeneye).  I used to wonder what I was going to do with the mass of photos I have collected; it seems now that they have been useful in my blogs. There are only two species of goldeneye ducks.  Common goldeneyes are found throughout North America and Eurasia.  In the Western Hemisphere, they breed in Canada and reside throughout most of the US and some of Mexico in the winter.  They also winter in parts of southern Canada; I have seen them overwinter here in Kelowna.  Barrow's goldeneye, on the other hand, has a very narrow range along the western coast of North America with some populations around the St. Lawrence River.  Barrow's goldeneyes overwinter along the Pacific coast and parts of south...

I photographed this in Leduc, Alberta, after a day of heavy rain. At the ripe old age of 66, I can say that I have seen some odd things in my time.  But I was unprepared for the truly strange sight of a coot walking along a flooded sidewalk, eating drowning worms as it went. It has been a wet summer in Alberta this year.  Rain, thunderstorms, tornadoes, and hail the size of baseballs have plagued the province.  And as each of us knows, worms come out of the soil when it gets saturated in order to breathe.  That's because an earthworm gets its oxygen directly through the skin, and water tends not to hold much oxygen.   And so, as I was walking around the Leduc reservoir, I noted a plethora of earthworms.  They were on the sidewalk, they were on the lawn, in dirt, underfoot, and in puddles.  There was a group of boys, armed with a tin can and fishing gear, collecting the largest ones they could find. The excitement in their raised voices was proport...