Monday, January 31, 2011

Coyotes Are Omnivores

Rib bones still attached to the steer carcass with their surface shredded
By the three-week mark of finding the steer carcass at the Dipper Ranch, the skeletal frame is becoming exposed.  All the major bones are still attached yet something is scraping their surface.  I assume this is from gnawing or scratching by the coyotes since they are frequently caught by the wildlife cameras at the carcass, and their teeth and claws are more capable of shredding hard surfaces than the beaks of the other common visitors - ravens and vultures.

Sunday, January 23, 2011

Beefeaters of the Santa Cruz Mountains

Two coyotes working the carcass on the night of Day 2.
After finding both canine and feline tracks around the dead steer, we decided to rig up a wildlife camera to see what predators returned. Wildlife cameras can be placed securely in the field to record wildlife activity over an extended period of time, at night, and in situations where wildlife would avoid locations or modify their behavior if a human observer was present.

On Day 2 of my dead-steer observations, I watched from the backyard with binoculars as ravens landed on the carcass and frequently flew off again throughout the morning.  By high noon, the cattle were peacefully grazing in the Golf Tee pasture near the carcass so I decided it was safe to check the wildlife camera.  When I opened the sheep gate to the Golf Tee, the living cattle looked up and trotted out of view.

Please note:  the remainder of this blog post contains graphic descriptions and photos of a carcass and predators feeding on it.  Do not select "Read More" below if you do not want to see these.  If your curiosity is greater than your gag reflex, press on.

Tuesday, January 18, 2011

The Bone Yard

Deer skull in the Bone Yard
The ground is covered with bright green grass which germinated in the fall rains.  Most days have been cool, so the new grass is still short.  The Roper taught me the cattleman's 100-degree rule:  if the sum of the daytime maximum temperature and the nighttime minimum temperature is more than 100 degrees Fahrenheit, then the grass keeps growing.  Conversely, if the sum is less than 100, the grass stops growing.  For example, last week the nighttime lows were in the 30s and the daytime highs were in the 50s, which adds up to the 80s.  No prolonged freezing weather, so the grass didn't die, it just stayed short.  For the next few weeks, any bones lying about the grasslands stand out in stark contrast to the bold green turf alluding to prior struggles between predator and prey.

There's a field below the house I call the Bone Yard.  On the edge of a dark oak forest, it is littered with a collection of white-grey bones old enough to have been separated and scattered into what I imagine are chewing piles.  Bones of a large cow, several deer and even a coyote skull suggest that this is some type of wildlife 'killing zone'.

Please note:  the remainder of this blog post contains some graphic descriptions and photos of a carcass.  Do not select "Read More" below if you do not want to see these. If you are interested in amateur wildlife detective challenges, press on.