First Frost for the Camera Checks

The air was cold and misty as we began our lion camera checks today. Driving out to the Preserve in the mist and early light, we were reminded of how important it is to keep an eye out for wildlife trying to cross the road at dawn. Even being mindful, collisions can happen but it’s always good to lower speed limit and be on alert for movement at the sides of the road as you drive, especially in rural areas. Dusk and dawn are high movement times for many animals but the habit of being aware of wildlife at all times is a good one to build!

Driving out to the Preserve on a misty morning, watching for wildlife that might be trying to cross the road. Erin Hauge

On this morning, the road to the Preserve was quiet. We packed up and with some extra layers on, we started out. It was a chilly 37 degrees at 7:00 am – our breath condensed in the air and there was frost on the ground!

Curly dock encrusted with frost in the early morning. Erin Hauge

As the season changes, bringing lower temperatures and heavier jackets for us humans, it’s hard not to think about all the birds and animals who are adapted for colder temperatures in many ways. Fur-bearers grow heavier coats and birds have insulation and thermo-regulation adaptations that allow them to wade and forage in the pond waters even as it gets colder. Admittedly Central Valley winters are milder compared to those at higher elevations, but it gets below freezing here and animals are pretty adept at adapting to whatever conditions they encounter in their own territories.

Northern Pintails near a flooded field pond on the Preserve, three males and a female. Erin Hauge

If the winter brings heavy precipitation, wildlife will be dealing with flooding as well, and their prime directive will be to stay out of the way of rising water – to survive. That will mean finding other shelter and food than the resources they’ve been using all spring, summer and fall.  Those young bobcats and their mom we saw last week on the trail cameras could very likely make use of multiple maternal dens if flood waters rise, changing the landscape of their home territory. Animals must be incredibly adaptable to the changing conditions in their habitat. If they can’t adapt, they must either find other territories or they die.

In the Field:

The roads we drive to the remote camera locations were definitely damp today and we drove carefully and with an eye to coming weeks.  If more rain pans out this week, the crew will likely be doing a lot more walking pretty quickly!

As it was, our crew discovered that the low-flow dam over the Cosumnes River is now under several feet of water.  We pulled the northern-most camera just in time last week!  An impressive 4 or 5 inches of rain fell in the Sierra and foothills last week and with this first big rain, low aquifers will be filling, the ground will absorb much of the rain and the river will fill.  Later in the season, as the landscape recharges with water and the ground becomes saturated, flood events become more likely.

We were able to walk across the Cosumnes River bed on this low-flow dam just last week, but not now! Photo Courtesy of Richard Larson

At our first cameras we heard a chorus of coyotes calling to the northeast, in the direction of our next camera. Coyotes use a variety of vocalizations and will often construct them so it sounds like there are more individuals than there are. So not only are their rich and beautiful songs used to communicate with each other, they can be a defense method that has evolved to let potential predators like wolves and mountain lions think there are more coyotes in the area than there actually are, and could be trouble if messed with. We stood and listened in the pale morning sun as the coyotes sang and called for a good five minutes.

Several members of a healthy pack family of coyotes seen on our cameras. Note the individual in the upper left corner! Photo Courtesy of Bureau of Land Management

We know there are no wolves on the Preserve but there are several healthy pack families in northern California!  The Lassen pack family recently grew with a litter of pups and Department of Fish and Wildlife (DFW) has shared some video from their trail cameras.  Note the cameras here are Brownings, just like the ones we use on the Preserve. The first video shows a wolf inspecting the camera. Watch how he decides to handle this little discovery!

Wolf checking out camera, Courtesy of CDFW:

And another video shows the pups out and exploring their front yard.  Look at those long, gangly puppy legs!

Pups exploring, Courtesy of CDFW:

Back on the Preserve, we headed out to one of our most remote cameras in the Tall Forest area and as we walked the muddy road we saw deer, raccoon and opossum tracks.  Right now there is a thick layer of leaf litter on the ground which also obscures tracks, even on the muddy road.  While we are always on the look out for any sign that could signal presence of a mountain lion, it’s hard to say where we’ll find our first tracks.

Each lion has their own ideas about how to encounter a landscape and also it depends on the day and the conditions that might influence how a lion travels.  Some lions would walk on the edges of roadways on the grassy, vegetated shoulder, still taking advantage of the open, clear travel corridor but close to the cover at the roadside’s edge so tracks might not be discernible.  Other lions might walk right down the middle of the road on one of the tire tracks, making chances of our seeing the tracks much greater.  Vigilance and patience are keys for the crew and we’ve always got our eyes peeled, scanning the roads as we go!

An example of the dense leaf cover on the roadways is illustrated in the photo below. At first we caught our breath as lion scrape can present in a similar way.  But upon closer inspection of the photo it turns out it may likely be turkey scratch. The reason is that if you look closely at the photo, you’ll see that the scratches form a ‘V’ in the center, as the feet move out at angles away from the body, the way a turkey or chicken would scratch in the dirt.  A cat would set scrape with front or back legs moving directly back, so the scrape marks would be parallel.   Based on the shape of this scrape mark, which way do you think this turkey was traveling?  (Hint: try scraping your back legs out at an angle away from your body, the way a turkey would and note the shape of the resulting ‘V.’)

These marks may have been made by a wild turkey, scratching and foraging under the leaf litter for insects and other food. Erin Hauge

We also saw a fun deer track. These tracks were made by two different deer, based on the angles of the tracks. The larger track with the splayed hoof would likely be the front hoof of a buck, as they have more weight distributed generally in the front and especially this time of year, coming in to rut. Bucks are starting to shed their antlers and they also gain bulk in their neck area, increasing power and stature for the competition for does and mating rights. Which deer walked by first?

The top track is likely the front hoof of a large buck, notice how the hoof splays under the greater weight that would be at the front end of his body. The smaller track may be a doe and for sure a smaller deer. Which deer came by first? Erin Hauge
Here’s a fun view of our camera, mounted on a post near a recently flooded pond, and the view the camera gets. We’ve recorded coyotes, skunk, raccoon, egrets and cranes on this camera so far. Now that the cottonwood grove that is good for wildlife traveling on the other side of the road is flooding up, we may consider moving this camera as the water level will continue to rise in this area as the rain falls, making it more difficult to access.
One of our cameras, mounted on a post at the turn of a roadway on the Preserve. Erin Hauge


Here’s the view the above camera gets. Wildlife passes on the roadway but there is also a well-traveled ditch that crosses the road at the telephone pole and to the left is a broad cottonwood grove that is now flooding up from the rains. To the right is an agricultural field that hosts lots of cranes right now! Erin Hauge

Our mountain lion camera project, supported with oversight by the Bureau of Land Management and the Preserve, is working to capture a lion this year on camera.  When that happens, the next step will be to involve the Department of Fish and Wildlife for the tracking, trapping and collaring of the individual.  There would also be DNA collection to determine where the lion came from and the general health of the lion. This will be an historic opportunity for the Preserve to document a mountain lion within its boundaries and to also expand a public awareness campaign about mountain lions and their role in the ecosystem.

Because of growing human development and because mountain lions are big and noticeable, Valley travel corridors are limited for lions. The Central Valley averages about 50 miles wide.  That’s a lot of miles to be on the Valley floor, trying to stick to cover and go unnoticed while looking for food and maneuvering the many obstacles that are constantly presented. The Preserve could be a prime transit opportunity to travel a good way across the Valley from the Sierra to the Coast Ranges and vice versa.  And if this is happening, it would mean that there would be genetic dispersal between Sierra Nevada lions and Coast Range lions and this is very, very good!  As seen in some lion populations, such as those in Southern California who are even further isolated by development, highways and disappearing travel corridors, a lack of genetic diversity can create in-breeding and threaten the survival of local populations.

View of the Sierra, to the east of the Preserve. Note the foothills on the left side of the photo, where mountain lions look for ways to enter the Valley as they disperse. Cranes foraging in the foreground. Erin Hauge


Mt. Diablo in the Coast Ranges to the west of the Preserve. Lots of agricultural land and major highways present large challenges for navigating mountain lions trying to cross the Valley. Erin Hauge

The volunteer mountain lion study now taking place on the Preserve is a key to finding out, through DNA information and a tracking collar, if lions to the east of the Preserve in the Sierra are managing to disperse through the Preserve and beyond. If this is happening, they may actually be breeding with lions from other populations to the west.  With our dedicated and motivated crew, it’s just a matter of time before we document a lion on camera, and that may set the ball rolling for further research on mountain lion dispersal in the Valley!

Mountain Lion 411:

Mountain lions are intelligent, stealthy and resourceful.  And we’re finding out through invaluable research that they are much more sociable than previously thought.  Here, for example, is a video of a lion group coming in for a drink at a water source during the recent drought in Colorado.  This is likely a family group, yearling siblings and mom or maybe just siblings.  By their size, they look like they’re getting close to dispersal age (1 ½ to 2 years old) so they’d soon be kicked out of the family group to go find their own territories and mates.  Check out this cool video from The Cougar Fund!

Meet the crew

Our amazing crew is out in the field looking for mountain lions and other wildlife rain or shine!

Meet Tom Palmer, Cosumnes River Preserve Volunteer Naturalist, Aerial Photographer, Amateur Astronomer and Citizen Scientist.

Crew Member Tom Palmer

We asked Tom: What do you like best about being on the mountain lion camera crew?

“I enjoy the camaraderie of working with other volunteers that have similar interest. Hiking to remote parts of the Preserve, the route to the tower pump camera seems a bit like Jurassic Park! Viewing and processing the images, always interesting often surprising. It’s a privilege to observe the wildlife and the ever changing seasons at the Preserve.”

Critter Camera Captures

Bobcat looking up! Maybe an owl or other night activity taking place just above. Notice the fur ruff or ‘beard’ under his or her chin. Photo Courtesy of Bureau of Land Management


Big buck crosses the camera range and gives it the ‘eyeball.’ Photo Courtesy of Bureau of Land Management


Skunk parade! Likely a family of three, mom and two kits. Photo Courtesy of Bureau of Land Management



Coyote catching a good whiff of something. Courtesy of Bureau of Land Management


All good coyotes have to stop and have a good scratch now and then. Photo Courtesy of Bureau of Land Management


Cranes stepping over from the agricultural field to the right, checking out the paparazzi? Photo Courtesy of Bureau of Land Management


Doe startling on our trail camera’s infrared flash. The cameras give off a red flash when firing in low or no light. These three does startled several times in the same sequence and ultimately passed by, continuing on their route. Photo Courtesy of Bureau of Land Management


Beavers are a keystone species for pond and river areas, helping with flood control and water filtration, and providing habitat for other wildlife that depends on aquatic food resources. Photo Courtesy of Bureau of Land Management


Three does walking. The first one notices the camera, even in the daytime. Photo Courtesy of Bureau of Land Management
CRP Mountain Lion Study

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