Environmental Study Of Lechtenberg Park

[Hill]

OK, I'll change my vote to Opossum after viewing more Raccoon skulls. BTW, a great source of skull photos at Thumbnails images for Mammals and Their Extinct Relatives

[Turtle]

OK, I'll change my vote to Opossum after viewing more Raccoon skulls. BTW, a great source of skull photos at Thumbnails images for Mammals and Their Extinct Relatives

 

 

Roger. I have saved your link to my reference folder & I'll edit the ID into the titles in a bit. Here's my last photo; the front view.

 

There does appear to be alot of chewing on the skull from the back of it forward, but the front part of the skull looks to be in pretty good condition, once its dried out.

 

:eek: Yeah, it's pretty 'juicy' still. :D I washed it in some bleach water and put it outside to dry and then it rained. :Alien:

 

[freeztar]

I read here that opossums have 50 teeth. Can you confirm this with your skull Turtl?

[Turtle]

I read here that opossums have 50 teeth. Can you confirm this with your skull Turtl?

 

When the skull has dried I'll make an accurate count. From the one photo I count about twelve teeth on just one side of the upper jaw, so that's ~48 by extrapolation.

 

Also interesting on the teeth, and particularly the exposed part Cedars drew attention to is that this may be a clear indication of age. I found a series of photos and articles from Hill's link on a different species of opposum that is worth looking at. :Alien:

Development in marsupials is of particular interest because many of the features that originate embryonically in placental mammals do not appear until after birth in marsupials. Thus, development of systems such as the skeleton are easier to study in marsupials making growth series such as this one invaluable to the study of mammalian evolution, and the relationship between ontogeny and phylogeny (Clark and Smith, 1993; Macrini, 2000).

Digimorph - Monodelphis domestica (gray short-tailed opossum)

[Turtle]

Today we hop back to dendrochronology. :hihi: :hihi: I sanded down the endcut from the Ash log I brought back for carving and then scanned it at 1200 dpi. I had a bit of a hump in the middle which kept me from the firm contact with the scanner bed one needs at that resolution, so I made a second scan for the outer rings and inset it in red outline. The thinness of the rings there is indication of some severe drought when the log died. :hihi:

 

The yellow outlined inset is a detail of the end-grain at maximum resolution.

 

Total age of specimen 78 years and diameter ~9". :hihi:

 

 

[freeztar]

That's a pretty big Ash!

The detailed scan of the grain is beneficial and very interesting. What do you suppose those grains are?

[Turtle]

That's a pretty big Ash!

The detailed scan of the grain is beneficial and very interesting. What do you suppose those grains are?

 

There are many Ash even bigger in the forest. Those grains are actually the xylem and/or phloem. I have seen forestry text books which use the pattern of the xylem & phloem as definitive identifiers of the type of wood. The pattern is unique for every species as I recall. Not so sure if there is a specific term referring to this or not. The text contained an index of microphotographs of many different species.

 

Scanning at 1200 dpi is as good (or better) an image than having a low power microscope.

 

I saw at least one wind-felled oak on the previous trip that is at least 2 feet in diameter. Securing a slab from it is no small chore but the information in the rings could be invaluable. Not so sure I'm ready for that much work yet, but I have it in mind. B) :hihi:

[freeztar]

There are many Ash even bigger in the forest. Those grains are actually the xylem and/or phloem. I have seen forestry text books which use the pattern of the xylem & phloem as definitive identifiers of the type of wood.

 

Ah Yes, the memories of plant biology come flooding back.

 

The pattern is unique for every species as I recall. Not so sure if there is a specific term referring to this or not.

 

Interesting, I have never heard this, but it makes complete sense.

 

Scanning at 1200 dpi is as good (or better) an image than having a low power microscope.

 

Not really.

I miss the low powered microscope at the Nisqually Reach Nature Center. I used to experience hours of joy from placing minerals and insects on the microscope. B)

I have a scanner (2400dpi), but it's just not the same.

 

I saw at least one wind-felled oak on the previous trip that is at least 2 feet in diameter. Securing a slab from it is no small chore but the information in the rings could be invaluable. Not so sure I'm ready for that much work yet, but I have it in mind. B) :hihi:

 

Waste not, want not. Go and get yourself a slab or two Turtl. B)

I'd come and help you if it didn't cost $400 to get to WA and back! B)

[Turtle]

Ah Yes, the memories of plant biology come flooding back.

:hihi:

 

Interesting, I have never heard this, but it makes complete sense.

I have looked casually for a similar reference online with no luck. I had a friend studying forestry and I read the books. As I recall there was a test showing the photomicrographs & the student had to ID them all. :Guns:

 

 

 

Scanning at 1200 dpi is as good (or better) an image than having a low power microscope.

Not really. ;)

I miss the low powered microscope at the Nisqually Reach Nature Center. I used to experience hours of joy from placing minerals and insects on the microscope. :)

I have a scanner (2400dpi), but it's just not the same.

B) Ok...different. ... in a better way. :doh:B) A valuable adjunct? It'll do in a pinch? Ever try to take a photograph through one of those microscopes? Of a wide field? I'm just sayin' is all.

 

 

Waste not, want not. Go and get yourself a slab or two Turtl. :)

I'd come and help you if it didn't cost $400 to get to WA and back! :)

 

Your enthusiasm at a distance is more help than you know. Priceless. :)This is a massive tree and taking the required size of slab from the required spot is so fraught with danger that nothing short of careful planning is going to bring home the bacon. I have lost pieces of limb cutting wood and it's no laughing matter; just ask Mr. Stumpy.

 

Here's a bonus high-res crop of the rings. No annotation except Mother Nature's B) B)

 

 

 

[Turtle]

I read here that opossums have 50 teeth. Can you confirm this with your skull Turtl?

 

Opossums are omnivorous and though their lack of speed keeps them from being an efficient predator, they are very capable of decimating a family of nesting pheasants, ducks, or quail at night when the birds are helpless. They have 50 teeth, more teeth than any other living mammal.

 

I counted the teeth in the found opposum skull today. The upper jaw has 11 per side, 22 total teeth, and no apparent room for more. The lower jaw has 11 per side, 22 total, and possibly an emerging tooth in the very back on each side. I can see just a hint of enamel tips but an otherwise complete covering of bone.

 

If we count the 'possibles' this is still only 22+24=46 teeth. The source may be mistaken or perhaps this is a young opposum and so not reached its full dentition.

 

Equally interesting from your link is that opposums are not native to the Pacific Northwest. :evil: This means war. :Alien: :eek:

 

One of the most interesting of Oregon's mammals was not even found in the state as little as 100 years ago. The opossum is North America's only member of the marsupials, a family which also includes the kangaroo of Australia.

 

Opossums may have been introduced into Oregon by immigrants who brought captive opossums along as future dinners. Some were released or escaped and have populated the Northwest with their descendants.

[Cedars]

I counted the teeth in the found opposum skull today. The upper jaw has 11 per side, 22 total teeth, and no apparent room for more. The lower jaw has 11 per side, 22 total, and possibly an emerging tooth in the very back on each side. I can see just a hint of enamel tips but an otherwise complete covering of bone.

 

If we count the 'possibles' this is still only 22+24=46 teeth. The source may be mistaken or perhaps this is a young opposum and so not reached its full dentition.

 

Equally interesting from your link is that opposums are not native to the Pacific Northwest. :evil: This means war. :Alien: :eek:

 

Looking at this link:

Order Carnivora

 

coyote has varied numbers of teeth, up to 44.

Raccoon has 40

Red fox has 42

 

Opossum page at above site:

Virginia Opossum (Didelphis virginiana)

 

An audubon site said up to 50 teeth on the opossum. Other DNR type sites list 50.

 

How long and wide are the skull? Looking at the graph paper, and assuming 2 squares = 1 inch it would appear to be 4.5 - 5 inches long as is.

[Turtle]

Looking at this link:

Order Carnivora

 

...

Opossum page at above site:

Virginia Opossum (Didelphis virginiana)

 

An audubon site said up to 50 teeth on the opossum. Other DNR type sites list 50.

 

How long and wide are the skull? Looking at the graph paper, and assuming 2 squares = 1 inch it would appear to be 4.5 - 5 inches long as is.

 

My bad...again. :Alien: The squares on the graph paper are 1/4". By the photos I count ~12 squares for a measure of 3". I would guess about 1/2" of the back of the skull has been chewed off.

 

[Turtle]

:shrug: Found some golden nuggets on Lechtenberg and Clark County eco-stuff. The black-crowned night heron is one of the birds I phtographed on the first expedition. :(

YouTube - Black-Crowned Night Heron - Nycticorax nycticorax http://www.youtube.com/watch?v=FmouaHmnVqk

Birds: Clark County provides habitat for more than 240 species of birds. These include relatively common species such as European starling, California gull, barn swallow, great-horned owl, and American wigeon, as well as relatively rare species such as great egret, purple martin, snipe, green or green-backed heron, and black-crowned night heron.

 

:D :eek:

 

>> http://www.ci.vancouver.wa.us/parks-recreation/parks_trails/planning/pdf/regional.pdf

[Cedars]

My bad...again. :eek::D The squares on the graph paper are 1/4". By the photos I count ~12 squares for a measure of 3". I would guess about 1/2" of the back of the skull has been chewed off. :shrug:

 

 

I think we have ruled out raccoon as a skull, the tooth count alone seems to be too high.

 

Fox and coyote are still possible based on tooth count alone. The shape of the skull tends to lead me to exclude coyote but because of the size, if it was a young animal, everything changes. I dont know that we will find a pic of a young coyote (+/- 6 months), which is the age I would look at.

 

I lost my fox skull years ago but via erroded memory, I am not leaning towards that animal.

 

If I have enough time this week, I will attempt to get some pics of the opossum skull I have. I am going over to where it is in storage, and I am pretty sure I know which box I put it in. But its a busy week I have coming up.

 

Did you find other bones in the area where the skull was, or was it just the head there?

[Turtle]

I think we have ruled out raccoon as a skull, the tooth count alone seems to be too high.

 

Fox and coyote are still possible based on tooth count alone. The shape of the skull tends to lead me to exclude coyote but because of the size, if it was a young animal, everything changes. I dont know that we will find a pic of a young coyote (+/- 6 months), which is the age I would look at.

 

I lost my fox skull years ago but via erroded memory, I am not leaning towards that animal.

 

If I have enough time this week, I will attempt to get some pics of the opossum skull I have. I am going over to where it is in storage, and I am pretty sure I know which box I put it in. But its a busy week I have coming up.

 

Did you find other bones in the area where the skull was, or was it just the head there?

 

Thanks Cedars; you rock! :shrug: Most of the other bones were nearby with the skull & jaw, but I didn't collect them. :eek: All were laying on top of the ground in an open area. :skeleton:

[Turtle]

I received a comment on one of the short bird videos I took in April. The commenter identifies the bird as a Tree Swallow.

 

Here's the clip and related info; if everyone concurs with the Tree Swallow ID I will edit the titles and my record. Takk!

 

YouTube - Tree Swallow - Tachycineta bicolor http://www.youtube.com/watch?v=7cZxBcN7Ac4

 

Look at the small beak, clean white throat and long primaries. It's a Tree Swallow. the date also backs up the ID.

 

Tree Swallow - BirdWeb

[Cedars]

I received a comment on one of the short bird videos I took in April. The commenter identifies the bird as a Tree Swallow.

 

Here's the clip and related info; if everyone concurs with the Tree Swallow ID I will edit the titles and my record. Takk! :D ;)

 

YouTube - Flycatcher ?

 

 

 

Tree Swallow - BirdWeb

 

Back in post #62 Cedars wrote:

 

The Flycatcher...

 

Have you considered Tree Swallow or Violet-green Swallow? They can appear dark when not lit well. The Flycatchers listed for your area dont seem to have the pronounced white throat and breast area this bird shows. Another possiblity is the Bank Swallow, at times the bird in the video seems to have a band across it breast, and other points it seems white.

/past Post

 

We dont have the Violet-green Swallow here so I could only suggest it via book information.