CRP Mountain Lion Study
Looking for All-Weather Lions!
We know mountain lions are out there but we did not see one on camera today. Our hard-working and excellent crew is in this for the long haul because everyone understands that sometimes it takes time to get the results you’re looking for. And we know that it’s just a matter of time before we capture an image of one of these intelligent and resourceful animals. We know there are lions on the Preserve at various times because we’ve had reputable and reliable sightings this year. We probably don’t have a resident lion but dispersing young adults are likely heading our way as they work hard every day to find a place to call their own. Paws crossed that soon we’ll meet one on camera!
The Sandhill cranes are finding refuge on the Preserve for the winter as the fields flood and the resulting ponds become rich with good foraging opportunities. Cranes are omnivorous and, in addition to fish, amphibians and aquatic invertebrates, they eat grains and seeds left from the year’s earlier agricultural harvests as well as snakes, insects, nestling birds, rodents, and tubers and berries. Cranes use their bill as a probe while they’re foraging for food on the surface and under shallow pond waters and on the levees and dry field areas near wetlands.
Cranes are known for their primordial, mournful trumpeting calls and you can hear them echo through the oak woodlands on the Preserve and across the open ponds. Those calls can be heard for up to two miles as family groups communicate and help to guide individuals in to roosting areas where other cranes are. Cranes have very long tracheas, or windpipes, that reach down into the sternum. This gives their calls a lower pitch with rich harmonics that can project over great distances. You may be watching a group of cranes in the ponds when suddenly one or more will begin to call out. Look to the sky and hark for incoming cranes calling as chances are pretty good that the group on the ground has heard the incoming fliers and is letting them know where they’re hanging out!
Sandhill cranes roost together in large family groups and this not only helps the youngsters with their social development, it gives the group protection against the many predators that are on the lookout for a crane feast. Young cranes that hatched in northern breeding grounds migrate south with their parents and are called colts. They continue to grow and mature here on the Preserve and practice their crane dancing skills that are used for courtship and also for defense against predators. Predators that can present a threat to injured, weak or inattentive cranes include coyotes, mountain lions, bobcats, foxes, raccoons, crows, owls and eagles. Cranes defend against aerial predators such as eagles by leaping and kicking with their feet. Terrestrial predators are discouraged by looking big and threatening with spread wings, hissing and kicking.
Cranes are watchful and wary. It’s important to always give them their space on the Preserve and be mindful of Preserve boundary signs, even when going for that photo op. Any time cranes go air borne because of disturbance or perceived threat on the ground, they’re expending an incredible amount of hard-gotten energy that’s needed to see them through the cold Valley winters and stay healthy and alert.
In the Field:
Today was sunny and cold as we headed out. No frost on the ground but it had rained pretty hard the day and night before so the roads were showing puddles and some mud. We were thinking about how the rain might affect mountain lion movement and behavior in terms of dispersal travel. It would depend on the individual and his or her experience and drive to disperse and probably also what kind of terrain they found themselves navigating in a storm. Would they feel compelled to keep moving in the rain? Would they find a dry spot and wait it out?
We were still able to drive to the cameras because the leaf cover on the ground is so thick that it provided a lot of traction. We’re looking at pulling a few of the farthest cameras closer in to more accessible walking distances but holding for now. With clear skies projected for the coming week, it may be that things will dry out enough for us to continue with cameras as they are for awhile. It will just depend on the weather!
The low flow dam was dry again but still showed signs of recent submersion. And it’s likely that yesterday’s good rain will bring more water down from the foothills and cover the dam again. The Preserve uses a flow gauge located in the foothills that gives the lower Preserve about 24 hours notice for increased flows that may present flooding so usually there’s a little time to prepare for access issues with things like the lion cameras.
The accessible crossing also means that wildlife is still able to use the low flow dam as a corridor to get back and forth from the more remote oak forests to the north over to the wetlands and slough areas farther south. Bobcats, coyotes and yes, mountain lions are still able, at this time, to move across the river using this dam and that is huge. When the low flow dam becomes covered in water for good for the season, wildlife will become aware of this and will have to adjust their travel patterns accordingly. The question of how wildlife, including lions, adjust and where they go when the water rises is a vastly important one that remains foremost in our minds as the rain falls.
Since it’s still pretty early in the rain season, aquifers and dry landscapes are still absorbing much of the precipitation but that will change if it turns out we have another really wet winter.
We visited the first camera this morning and got another great view of how the river is rising. We stood at the same spot where we’d taken the second photo below of the Cosumnes River two weeks ago and it was easy then to still see the sandy river bottom and the tracks where animals had walked along the dry bed. Today, you can no longer see the bottom of the river and there’s a perceptible current!
We tended to the camera and battery level was good. We let camera batteries run down to 25% before we change them to get best value. The cameras take 8 AA lithium batteries and when all conditions are ‘go,’ the batteries can last for up to four months or so. We had just over 250 images, which is a pretty good average for a week’s worth of camera captures.
One of the things we expect as the weather turns cold and wet is more spiders who like to take refuge behind the cameras in the casings! Our crew was not disappointed today! Each of us had stories to tell of spiders large and small popping out of the casings and camera covers as we opened the cameras up to retrieve SD cards. Spiders seem to find the casings particularly appealing shelter from the Preserve’s winter weather. They’re pretty harmless and I’m sure just as surprised to see us as we are them. They always just jump off and go about their way but they definitely get our attention!
This camera is located on a levee just above the Cosumnes River and overlooks some active game trails. The rain has greened everything up and this camera may require some vegetation trimming of the low grasses and weeds in the coming weeks.
It turned out that most of those 250 or so images were turkeys! No doubt giving thanks for living through another Thanksgiving feast without being on the table!
We saw lots of great tracks back near the low flow dam, including coyote and great blue heron! And we found some very large scat, likely coyote.
There’s a healthy coyote pack family currently running on the route covered by this camera. The scat pictured above is hairy, twisty and loose and collapsible when you squeeze it, qualities of coyote scat. Coyotes can’t digest hair the way lions and bobcats can so you actually see animal hair strands twined in the scat. And instead of straight, defined fecal segments with blunt ends, the way you’d see in a cat scat, these segments are twisty and end in points. Cat scat is solid when you squeeze it and breaks apart to a felt-like quality inside because cats have evolved to do a better job of digesting all the hair they consume with prey.
Learning scats and tracks takes perseverance, repetition of knowledge and lots of practice with ‘dirt time!’ And even then, sometimes you’re just making a best guess based on the information you have. Regardless, keep your eyes open and your awareness on the dirt as well as the landscape around you – think details plus ‘big picture!’
Meet the Crew
Our amazing crew is out in the field looking for mountain lions and other wildlife rain or shine!
Meet Kristin Harrisberger, Cosumnes River Preserve Volunteer Naturalist, Citizen Scientist and Grounds Supervisor at the Sacramento Zoo.
We asked Kristin What do you like best about being on the mountain lion camera crew?
“My favorite part of working on the mountain lion project has to be the crew. I love being able to get out and enjoy the beauty of nature with like minded individuals. We each have different background but share the same goal. I have been inspired by each member of the crew to continue forward with out search. I look forward to my daughter growing up and being able to eventually volunteer as well. It’s essential for our youth to understand and respect nature… and I know that she’ll find it at the Preserve.”
The Sacramento Zoo has generously given a grant to the Mountain Lion Foundation that is currently supplying some trail cameras to the Cosumnes River Preserve for the mountain lion project.
Here are three ‘mystery’ photos from this week’s cameras! Take a look and before you peek at the answers, take your best guess as to what’s going on in the photos!
We get photos every week that give us a double take for a variety of reasons. We look to the image sequences and time/date stamps to help us sort it out. And we have the support of BLM biologists and knowledgeable trackers to help us consider options when we just aren’t sure. Okay, take your best guess and look below for the answers!
Be sure to check in next week as we continue our search for a Mountain lion on the Preserve!
Critter Camera Captures