Blog by Erin Hauge
We were out on the Preserve this morning before it got light. Coyotes were calling as the dark sky began to lighten in the east and rabbits fleetingly crossed our path as we walked along to collect our go packs and equipment to head out into the field.
There was another barn owl kill in the same area where we have found a number of barn owl kill sites over the last few weeks. This one had the scattering of feathers but also a trail, a wing feather on the ground here, a downy underfeather dangling from a grass strand there, over towards a stand of tall oak and cottonwood. It was even possible to see where an animal had moved through the grass bank there as they walked, maybe with the barn owl carcass, into the protective undergrowth beneath those giant oaks.
Kill site where a barn owl died. Left, overview of the site. Right, the ring of feathers created as the owl was likely knocked out of the air by a great horned owl or other large raptor. Erin Hauge
While terrestrial predators like bobcats do prey on barn owls, it’s unlikely that this is the work of a mountain lion. Looking at the consistent display of feather rings, it’s possible most of these kills are being made by a great horned owl or some other large raptor. When a predator bird slams into a prey bird in flight, it knocks out a bunch of feathers, creating the ring of feathers seen on the ground. They’d have to land to finish the kill and then probably carry the carcass off to eat in a safe place, explaining why we don’t find any body parts.
In other news our team found a very large scat today on the Preserve near one of our cameras to the north! Just below are an image of bobcat scat found today for comparison along with the large scat that was found by one of our crew members. We can’t overstate the value of always carrying a ruler because without scale reference, these images would be much harder to interpret. As it is, you can see that the bobcat scat is about 7 inches long and the lion scat is about 11 inches long. Big difference! Bobcat scat can be anywhere from 3 to 9 inches long and 1 inch or less in diameter. Mountain lion scat can be from 6½ to 17 inches long and ¾ to just over 1½ inches in diameter.(1) And the clearly defined segmentation and hard, compact composition could indicate possibly feline scat in both photos. Coyote scat can be large, 5 to 13 inches long, but it might appear as more twisty and squishy and undigested hair from prey and vegetable matter can be easily visible.
Comparison between two different sized scats. The scat on the left may be bobcat. The scat on the right is much larger and could be mountain lion or possibly coyote. Emma Greene image on right. Erin Hauge image on left.
If you see interesting scat or tracks in the field, put a ruler down and take a picture! Then take a larger scale photo of the scat and the surrounding area as well. And take note of the surroundings. Are there other animal signs at the site that could help tell the story of who made the scat and where they might have been heading?
As fall approaches, we’re beginning to think about what kind of rainy season we might have this year. Will it be intense and wet, like last year? If so, the Preserve could flood to historic levels once again and all the wildlife will adjust their travel, sheltering and food searches accordingly. If it’s a drier rainy season, more of the Preserve may remain accessible to wildlife, including mountain lions, through the winter.
The Cosumnes River Preserve in late September. Erin Hauge
Rainfall impacts the lion camera crew because as the water levels rise on the Preserve, we’ll need to pull in cameras so they don’t become submerged. Last season, all cameras were in for a time and we weren’t able to deploy all the cameras again until May, which is late in the season. With any luck, we’ll be able to keep cameras out late into the season this year before flooding requires us to bring them in. We don’t want to miss any kitty action out there!
Mountain lion photo courtesy USFS.
Our current goal has been to get two more cameras out but with the late fire season, we haven’t been able to mow one remote area that could be a promising lion hot spot and we just pulled in a broken camera which means we’re down one! With a mountain lion possibly on the move we just completed a thorough camera audit of the 11 cameras we have deployed. And we were able to replace the misfiring one with a working camera. This means that all formatting and operations functions were carefully checked on each camera to make sure that settings are correct, including date and time, operation mode and other image data. Batteries are juiced and SD cards are formatted and working. There’s no doubt we’re ready for a lion to make an appearance. And we’ll stay at the ready because, while ‘thinking like a lion’ is challenging and every lion is an intelligent individual making decisions on the move, our team is out there every week looking for those lions!
(1) Elbroch, Mark “Mammal Tracks and Sign, A Guide to North American Species” Stackpole Books, 2003
(This is an excellent and comprehensive guide if you’re interested in learning more about tracks and scat!)
View on the Cosumnes River Preserve. Erin Hauge
Coyote and turkey. Courtesy of Bureau of Land Management
Bobcat. Courtesy of Bureau of Land Management
Coyote greeting! Courtesy of Bureau of Land Management
Fawn. Courtesy of Bureau of Land Management
Deer, mouth open - mouth closed. Courtesy of Bureau of Land Management
