Saturday, October 13, 2018

A NSWO BAND RECOVERY- A FIRST FOR THE BCCER!

At CSU Chico Reserve's we have banded almost 900 owls since we first opened the monitoring station in 2005. This is the very first time another station has recaptured one of the banded owls from our site. And look at the traveling this little lady did~ approximately 800 miles straight line distance! Of course that probably was not her flight itinerary, maybe making stops in Oregon and Washington? You can see by the banding certificate and map below sent to the "finder" by the Bird Banding Laboratory that we at the BCCER site captured the bird as a Hatch Year (she was hatched in 2017) during fall migration.

Information and points where this female HY bird
was banded (blue, 2017) and recaptured (yellow, 2018)
Then, this October 2018, Rocky Point Bird Observatory in Canada, netted her again during fall migration. It's been a full year since her original band date. Where has she been?  We can only guess between point A and B but I assume she flew north in the winter/spring 2017 to breed, maybe somewhere in Canada. Then she flew south through the tip of Vancouver Island at the RPBO. Here her information was input into the BBL's "report a band site" by Rebecca and she received the certificate of appreciation showing the owl's information.

The certificate banders receive from the Bird Banding Lab
when they report a banded bird
Foreign Recoveries (a recapture of another stations bird), are much more common where the NSWO banding stations are denser, like back east and Canada. They are valuable to determine timing, direction and distance of migrating owls, and longevity. Check out the map below for active owl stations across the country
Map of active NSWO banding stations (red dots) in 2010

2018 NSWO MONITORING OFF TO A GREAT START!

Ken and banders Wyatt and Dawn, plus a great group of veteran and seasoned volunteers will be running the NSWO station at the BCCER again, for the 16th season! We had a training for new assistants to show the banding process, the data we collect, and the value of long term monitoring. Ken and Wyatt conducted their first banding on October 8 and were surprised with an evening of 10 new owls! Eight of the owls were hatched in 2018 (HY) and 2 were second year, SY, hatched in 2017.  It appears that it could be another great year for owl reproduction from this population of owls. If you want to learn about the owls, contact Program Director Ken Sobon, ksobon@thermalito.org.

The owls are curious and often look at you before take off.
Photo by Ken Sobon

Friday, April 20, 2018

NSWO CSI; Murder on the BCCER

Banding an owl tells us many things including age, longevity,  movement, residency and death.  In late February, Jon Aull, Outdoor Education Coordinator at the Reserve contacted us about a saw-whet he had found predated, band number 1104-43252.
Predated Saw-whet Owl at the BCCER
Note the band on the right leg. (Jon Aull photo)
I looked it up in our database and found that this individual was banded on October 28, 2017 during fall migration on the Reserve. We could not sex the bird due to overlapping measures of wing chord and mass (84 grams), but we did age it as a hatch year. So this owl did not survive a full year. If a bird makes it out of the nest, the first year becomes the most vulnerable period in their lives. There are predators, disease, and man-made obstacles in the wild, and young birds learn through experiences that they don't often survive.

I think that maybe a great horned owl caught this owl at night and had half a meal, or maybe a mammal plucked the saw-whet from a low perch during the day. I don't believe it was killed by a diurnal raptor like a cooper's hawk, because the owl would have been surrounded by plucked feathers. 

If you find a banded bird contact the bird banding laboratory (BBL) and you will receive information about that bird  AND a certificate of appreciation. Thank you!






Thursday, April 19, 2018

BEST YEAR EVER 2017, 162 NEW OWLS!

Fall 2017 migration season kept the BCCER owl banders very busy, and very happy! We had 175 total captures including 162 new owls and 13 same season recaptures. The owls consisted of 121 females, 11 males and 30 of unknown sex. We had a whopping 120 hatch year owls (owls hatched in summer 2017) and 40 owls were two years and older (17 were three+ years!). See the previous post for more details: http://birdbling.blogspot.com/2017/11/one-hundred-and-twenty-nine-owls.html


Friday, November 3, 2017

ONE HUNDRED AND TWENTY NINE OWLS!!!

Yep, that's how many owls we have banded since our first night of owls on October 12, with an opening night of 13 owls! Now on November 3rd, we still have a couple of weeks of migration (October 15-November 15, with sampling on either end). It is our highest number of migrating owls since we have run the station annually in 2005. VERY exciting! The majority >80% have been Hatch Year (HY) owls, hatched sometime this summer in 2017. All these youngsters are easy to age. Here's how. We look at the dorsal side of their wings to see what their molt pattern looks like. And we use descriptions like chocolate to describe the color differences between new and old feathers. We look at the remiges; the primaries (10) and secondaries (13).
Hatch Year, all feathers one age (uniform molt pattern)

Second Year, outer primaries and inner (closest to body) secondaries have been replaced,the new feathers are darker(dark chocolate) and of higher quality then the old,
retained (milk chocolate) feathers. 

After Second Year, (over 2 years old) has three generations of feathers
fresh (dark chocolate), old (milk chocolate) and very old (old milk chocolate!)
And then, there is the magic trick to confirm our age determination. We look at the ventral wing and turn on a black light and like a black light poster, the feathers glow! It's actually a pigment called porphyrin. If you like chemistry, go here to learn more about porphyrins.

Notice the difference in porphyrin glow? As the feather ages, the pigment ages too;
the older feathers don't glow as brightly as the fresh feathers. How old is this bird?



Friday, October 20, 2017

OH, AND THAT SPIDER....


The wolf spider! Volunteer Mary Muchowski found this lady on our way down to check the nets. Guest Dan Roskopf was with us to meet a NSWO, and took the spider's photo. She's a protective mother, carrying tens of babies on her back. Apparently this is rare spider behavior, only wolf spiders do it, so I feel very excited that we got to see her! Watch this video to see a live version of active young wolf spiders: 


Wolf spider mother and hitch-hiking babies, Dan's photo
there is always something interesting in the night.... Come join us and see for yourself!
Dan and Mary with NSWO, Dan's first!

OWLS, BATS AND SPIDERS, OH MY!

Owl season was off and running on October 13, 2017 when program directors Ken and Julie and volunteer Mary, banded a whopping 13 owls!! Since then, we have been out six more nights and have banded 5, 5, 2, 7 and 6 owls, = 38 owls, averaging 6 owls a night. A great surprise, we had one recapture from our Snow Goose Festival event from January 2017, showing migration site fidelity. Recapture information is always valuable.
  • NSWO profile. They are amazing tiny predators, and captivate all that meet them!

Lucky guests, meet and release a NSWO

Volunteer Carol Anderson with saw-whet owl.
Volunteers help drive our program, thank you!

All our other owls are new owls without bands and most are hatch year birds, meaning owls were hatched in summer 2017, and it was a great summer for saw-whet owl breeding! We have also captured and released 3 pallid bats, a flying squirrel and a katydid!