To add to my previous post I thought I’d share one of the more impressive series of images from a den thus far;
We believe the Red-tailed Hawk you can see entering and exiting the upper left of frame in this series was attempting to steal the prey item being carried by female 199B9 (center frame) to her natal den in April 2011. Whatever the reason, she survived unscathed and went on to occupy 2 maternal dens through the 2011 season before her VHF transmitter finally failed.
In a somewhat desperate bid to up my posting rate I’m going to revisit old ground in this post and return to a brief email debate from last April.
And so a brief background is in order…
As we build up to this years denning season we have begun the task of collating and analyzing our camera data from the first two denning seasons on Stirling. As many of you may know the season really begins to heat up in early April as we confirm natal dens (a natal den is the den in which a female gives birth to her kits) by performing walk-ins on stationary females. It is usually on the second walk-in to a given tree that we consider the female has indeed denned. At this point we set a series of remote cameras around the den structure in order to passively monitor the females activities. Through the denning season a female Fisher will usually progress from her natal den through a number of maternal dens (a maternal den being any den occupied after the natal den). Thus one of the most exciting things we see on our cameras is the female carrying her kits out of the den, this gives us a great opportunity to count the number of kits.
So here the debate arises. While going through our pictures of female 17582’s natal den from the 2011 season I came across some familiar images, the first image is of 17582 moving her first kit from the natal den to her first maternal den roughly 100 yards away. Nothing too contentious there.
The picture below was taken 20 minutes later and appears to show her moving a second kit, or potentially a second and third kit at the same time, as the wily Roger Powell contended.
We seem to be having a spell of good weather over the district currently which is allowing a little more freedom in the field since our return from the West Coast Fisher Symposium in Sacramento. There is still a little snow on the roads at higher elevations and the peaks of Lassen to the North are finally showing white but skies are clear and most of our access points are open.
Yesterday saw an overdue visit to some of our more Northerly females on the edge of the Ishi Wilderness, we currently know of two females in this area, both of whom were located yesterday.
Today I managed the first walk-in on our most recently collared female (see post January 25th 2012). I found her in a draw high above Big Chico Creek keeping an eye on me from the canopy of a large Douglas Fir. The photo fails to do her justice but you can make her out peering down from a mass of branches some 100 feet from the ground.
This being the first time we’ve had contact with her since she was collared I was pleased to note that she didn’t appear agitated, neither vocalizing nor attempting to move off while I was observing her.
Though the aim of our trapping efforts is to catch fishers, we sometimes find non-target species in the traps. Striped and spotted skunks, ringtails, grey fox, and squirrels are the usual suspects. Some of them even seem to find the wooden cubby of the trap comfortable! Last time I caught a ringtail, I opened the back door of the trap and left to do other work. Upon returning 4 hours later, it was still resting in the box!
With the belated and thus far underwhelming winter storms making an appearance recently a few of us have found ourselves with time on our hands away from the field. In light of this situation the ever industrious Aaron has, among other assignments, set us to work organizing a digitalized mountain of trail camera pictures.
As a (more?) naïve youth I used to quite enjoy going through these pictures, then I came to work in bear country…needless to say, the novelty has worn a little thin. For the uninitiated; it is a favorite pastime of black bears to find, wander around in front of and then try to eat trail cameras, this can become a little tedious to watch the 10th or 100th time you see it. Nonetheless, we do get to see some of the more reclusive local residents going about their business too.
I thought I’d share a few recent favorites to add a little color…then I realized they were all night shots.
Today we captured a new juvenile fisher near Hwy 32! This is the 5th juvenile female fisher captured this year (2011-2012), and the 9th total juvenile. She was collared with a VHF transmitter and we will begin tracking her as much as possible in the near future. This is exciting news because thus far 6 fishers have been documented to have died on our project. Capturing 9 juveniles that are independent of their mother’s and surviving indicates that at the least we have replaced those deaths with fishers born on the study site. This is one indication that the populations may be stable or even growing.
Currently we are tracking 24 animals with VHF transmitters and another 9 with Argos satellite (PTT) transmitters. Capturing, collaring and following many animals is important to improve our understanding of what habitat requirements they have and how that is influencing our incipient population.
The first major winter storm we’ve had since November is upon us. So far we’ve gotten a few inches of snow at the lower elevations of the study site, but maybe quite a bit more up high. This makes the roads and conditions difficult and so not many telemetry points being taken right now. it does allow us to work on data entry and analysis a bit more, and with the upcoming meeting of the The Wildlife Society it is not a bad thing. A positive aspect is that we can do some snow tracking of fishers when the weather is bit nicer. It is always fun to follow fishers for a while.
After three years of much discussion, thinking and hard work we have finally finished moving our target number of fishers (24 females and 16 males). We have taken fishers from many places in Northern California on publicly and privately managed lands. Fishers have been released in Deer Creek, Butte Creek and and the West Branch of the Feather River. These represent 3 distinct and important watersheds that occur on the Stirling district. Our goal in releasing fishers in these diverse and widely distributed areas are to place fishers throughout much of the district, allow them access to varied land cover types, and to avoid placing them in the established home ranges of animals that have already been released (this was primarily a concern in years 2 and 3). Fishers often do not stay in the areas we released them in, but to a large degree they have settled over a large portion of the Stirling district. After 2 years of study we know fishers occur in all the major water sheds located on the Stirling district and in lots of diverse areas and elevations (ranging from 2000 to 6000 feet).
A lot of people and groups have made this happen and it has been an interesting and fun group to work with. It is clear that we could not have gone as far as we have without all those contributions.
Now that the work of moving animals to Stirling is over we will concentrate our efforts on the animals that have been moved and their offspring. In addition, we still have lots to learn about what areas they prefer and how this affects the success of the reintroduction and what that information tells us about what fishers need. It promises to be a lot of fun!
Roger waiting for male F605B to leave the box
Kevin releasing male 18AA5 (fisher is on left side of picture)
It’s that time again! The annual meeting of the Western Section of the Wildlife Society is being held at Woodlake Hotel (formerly the Radisson) in Sacramento, CA from the 1st through the 3rd of February.
As a special bonus, there will also be West Coast Fisher Symposium from the 31st of January – 1st of February (brainchild of our own Scott Yaeger). Link to the symposium flyer can be found here. The format will break from the traditional “project update” and instead invited speakers have been asked to address key questions during a presentation and then join an audience/panel discussion. This is a great opportunity to interact directly with the researchers (besides, we’ll all be there!). We hope you can join us as we present and discuss varying conservation concerns relating to fishers!
We’re 3 years into the project, and we’ve nearly released all our fishers. We attracted a good group, with several dozen participants to help us loose 4 of the final 5 animals to SPI’s Stirling tract in the Northern Seirras east of Chico on the 8th of December, 2011. We have released 39 animals to date. We were fortunate to receive a good bit of attention from the media; take a look!
We were also very happy to have the woodshop class from Anderson High School in Anderson, CA come out to participate. They were kind enough to use some of their time last fall to build cubbies onto 40 live-traps that we put into service late last year. THANKS!