Tuesday, February 18, 2014

Zombie Rodent

Mountain beaver (a.k.a. aplodontia) is one of the unusual mammals you get to practice camera trapping on at this workshop in the Sierra Nevada mountain range of California. It took me several months to realize why this particular camera, Wingscapes Birdcam 2, would occasionally get great close-up nighttime photos with flash but never more than one. Something about the electronics in this model shut the camera down after one or two flash photos. This model is now discontinued. For more info about this unusual burrowing mammal go here and a fellow alumnus has better photos of the zombie rodent here.  
Dr. Chris Wemmer announced his 2014 camera trapping workshop - if you ever wanted to get serious about using trail cameras to understand the mammals on your study site or the back-40 then this five-day adventure is for you. In 2014, it will be July 13-18 at the Sierra Nevada Field Campus in beautiful Yuba Pass, California.

Mountain beaver pushing dirt out of its burrow. At the workshop, three of us students set up several cameras on a mountain beaver burrow to compare the different cameras. Unfortunately, three sets of LED lights were washing out the  entire scene. We learned there could be too much of a good thing but that's when we came up with the moniker "zombie rodent" for the mountain beaver.  
Click the link above to learn more about this year's workshop. The announcement reminded me of how much I learned at the workshop last summer. Get low - that is the major technique I've practiced in the seven months since then. I've deleted many a photo of me crawling around in front of the camera or staring into the sensor to test the aim. But as you can see in the photos I've included in this post, fine-tuning the aim is resulting in better wildlife photos.

In December while testing new cameras for a bobcat project, I placed them near the Dipper Ranch house so I could frequently check on them. Black-tailed deer, gray fox, mountain lion and striped skunk paraded past the camera over six nights. One problem with working with several brands of cameras is that each one operates differently. The date stamp on this photo is wrong because I forgot to reset it after replacing the batteries earlier in the evening.  Fortunately by my field notes and by the time stamped on a subsequent photo of a truck passing by, I could correct this date to December 19, 2013 at 1:30 AM on the photo's metadata. Placing cameras at different locations, even incidentally in this case, is showing us how the lions are traveling from the lower to the upper parts of the ranch.  
Move your cameras around every few weeks to get a good idea of where the animal traffic is. When you find a wildlife hotspot, leave a camera there to assess patterns over a longer period. Go back over each set of photos several times - there's more info in there than you first realize.

The young bucks started losing their antlers in mid-December. Photos of the older bucks show them holding onto their big antlers until early January. I'm sure that fact is in a book somewhere but it's rewarding to witness and learn it myself. Of course, I should probably verify it with a few more years of data.
 It took me months of trying different setups to decide that the best position for a camera at this spring is on the slope above. Over the dry summer, fall and winter, the trail cameras showed that this spring was visited by black-tailed deer (in all their family relationships, seasonal changes to antlers and coat, even signs of disease), cattle, mountain lion, coyote, raccoon, striped skunk, grey squirrel, dusky-footed woodrat, mice, mourning dove, dark-eyed junco, great horned owl, saw-whet owl, a large covey of California quail, Stellar and scrub jay, varied thrush, and somehow the camera also triggered on lizard, banana slug and California newt. This spring is an excellent location to track seasonal and long-term changes of wildlife on the Dipper Ranch. Somehow, I've managed to winnow this collection down to 476 photos for a ten-month period and I still go back and analyze them for patterns.  
On the other hand, the frustrating stuff -  I don't have enough memory on my computer for all these photos and videos. I've purchased six additional trail cameras since then, sent another one back to the manufacturer for testing, still hang onto the old ones just in case I can repair them or steal parts from them one day, and bought/begged/stolen/designed different mounts. Cam trap equipment is starting to take over my living room.

I even used a trail camera to determine what was making all the racket in the attic - a dusky-footed woodrat. After reviewing several nights of photos, I realized where to look for an entry hole and that I had only one rat. With this information, I was able to develop a plan to move this native woodrat to a more suitable location outside and seal up the entry hole.  
I need a better system for organizing photos so we can more quickly and consistently determine relationships between the animals photographed on different dates and at different locations. One of my camera trapping classmates recently pointed me to this free software from the Small Cats Conservation Foundation which systematically relabels photos from your camera traps to help organize and analyze them. Has anyone tried it yet? I may convince a student to test it on our bobcat project.

Rufous hummingbirds nest north of California but by early July the males return to the Sierra Nevada mountain range. The females and immatures will arrive later in the month to nectar on the flowers still blooming at these high elevations (Storer et al, 2004). Because the mountain larkspurs were growing in discrete patches at the field campus, from the top of the hillside you could look down and watch the bright orange male hummingbirds patrol and defend their individual fiefdoms.  (Taken with my Nikon 7000, not a camera trap.)
One afternoon at the workshop, I went to check my Birdcam at a mountain beaver burrow. On the way back, I took a detour past the mountain larkspurs. In their purple glory, I spaced out and spent 2 hours watching the rufous hummingbirds check and recheck the towering 6-foot spires for nectar, and battle each other at their territorial edges. As a result, I missed the afternoon session on camera sensors and security. Yikes, that was a goof! On the other hand, Yuba Pass is such a magic place you can completely forget about everything important and just spend two hours watching nature flow by. That's a sweet moment of forgetfulness in my life.

If you take a class at San Francisco State University's Sierra Nevada field station, you can arrange to arrive a few days early or stay afterwards to explore the nearby alpine trails of the Sierra Buttes and Lakes Basin Recreational Area. Now I just have to decide whether it will be Sierran flora, wildlife photography, or writing that I will study at Yuba Pass this year.

Who says camera trapping can't be art?  
The Camera Trap Codger will publish a camera trapping book one day and then he will be too busy on a world-wide book tour to have time for workshops, so go get your wisdom first-hand from the Codger now.

The Bushnell catches me looking for tracks as I hustle to get home before sunset. All the 'hip' camtrappers wear pink.  
Black-tailed deer, Odocoileus hemionus columbianus
Dusky-footed woodrat, Neotoma fuscipes
Mountain beaver, Aplodontia rufa
Mountain larkspur, Delphinium glaucoma
Mountain lion, Felis concolor
Rufous hummingbird, Selasphorus rufus

Tracy Storer, Robert Usinger and David Lukas, Sierra Nevada Natural History, University of California Press, 2004.

1 comment:

  1. Great post. Terrific cam trapping tips and wonderful pics. Love that Aplo shot - really shows their habitat.


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