WPBO Owls

Monday, May 19, 2008

We want to thank all of you who expressed your interest in the Saw-whet nest box project after our presentations at this years Spring Fling and the Paradise Township meeting. For those who were interested in building their own boxes, here's the link to the nest box plans. This company also sells nest boxes on their website.

http://www.shawcreekbirdsupply.com/plans_saw_whet_owl.htm

One study reported that most of the nests occurred at a height of 3.5m-6m, or 11'8"-19'8". They prefer relatively open woods, either coniferous or with a mix of conifers and deciduous trees.

We hope this project will provide insight to our summer owl banding research. Over 3 weeks in 2006 and 2 months in 2007, we banded over 700 juvenile Saw-whets at the Point (above photo: a juvenile Saw-whet at the Point, July 2007). We really have no idea where these birds are coming from. We hope by banding nestlings on the Whitefish Peninsula, we will begin to gain knowledge into what role the local populations play in the summer owl banding at the Point (photo below: nestling Saw-whet being weighed at nest site, summer 2007). The spring owl banding will be taking all of our energy for a few more weeks, but we hope to get going on the nest boxes in mid-June. Any other locals interested in having a Saw-whet nest box installed on their property please let us know, email at wpbostaff@gmail.com

Sunday, May 18, 2008

Here are some more exciting numbers for you dedicated bloggers. We've reached 1,000 owls and still will be banding until May 31st...as long as we don't keel over first. Also, we banded our 100th Long-eared Owl for this spring! The Long-eareds are still migrating, which is unusual. We have had lots of visitors lately, in particular one young lady-Ms. Sarah Toner, who was very excited to release a Long-eared. She had read our article on Aging Saw-whet Owls in our membership newsletter "The Migrant", and aged the first Saw-whet we showed her correctly. A future owl bander, I'm sure!

Please don't forget that our Birdathon is coming up in a week or so. If you haven't pledged, please help us out. The summer owl research depends on you!

Sunday, May 11, 2008

Big Owls.

That is pretty much all we have to say. In the last three nights we have captured 14 long-eareds, 6 Barreds, and 3 Great-Horneds. Over the last 15 spring seasons only 3 Great Horneds have been captured, so banding 3 in 2 nights was very unexpected. While we are still not seeing the numbers of Barreds that Keith and Wendy experienced last fall, they continue to be a nightly presence. Last night we tracked down a screaming Blue Jay, knowing it was being preyed upon. We expected to find a larger owl, but were amazed to find that a Saw-whet had taken a Blue Jay! It's easy to forget what capable hunters those little cuties are.

***The sightings blog is now being updated. Visit www.wpbosightings.blogspot.com

Wednesday, May 7, 2008

It seems that the Barred Owls have increased their presence around the point in the last week or so. We haven't captured very many new ones, but have had some recaptures of banded Barreds from last year and this year. On the same subject, we have captured 30 encounters (already banded) owls this spring. Some are ours from years past. One last week was a juvenile from last summer, which was very exciting. Yay for the summer owl project!

Saturday, May 3, 2008

Well, the owls have slowed down a bit due to the bad weather recently. However, last night we saw our first Great Gray Owl of the season. We saw it only once during our first net check, but it gives us hope for May! Our total numbers for the season thus far are very encouraging, with over 800 owls banded since March 15th. Since we only banded 26 owls in March, April was a very busy month.

For those who would like to visit the Bird Observatory and see the owl banding, here are a couple of pointers.

1.We band starting at dusk. This means that we set up the nets at that time (around 9-9:30pm), and the first net check is usually around 10:30pm. This will become later as the nights get shorter. Visitors can wait behind the WPBO gift shop while we check the nets. If we catch any owls,we will bring them back to be banded. Visitors are welcome to observe the banding and release procedure. No flash photography please.

2.We do not band in high wind or rain. If the lights in the gift shop are off, so are we!

3.The owl banding is a very special activity that is free to the public at Whitefish Point. We really enjoy educating our visitors about owls, and hope that you will consider making a donation to WPBO. Your support is what keeps our research going!

This leads me to one more announcement:

the WPBO Staff Birdathon 2008 is happening in May. This is an event to raise funds for our summer owl banding project that has been going on for 2 seasons. Some of you have read our blogs about this amazing juvenile Saw-whet Owl movement. Anyway, the WPBO staff known as the "Northern Saw-whats" team will record the number of bird species seen in the Whitefish Point Peninsula during a 24 hour time period. We hope to see about 100 species. We are looking for sponsors for this event.

Becoming a sponsor is EASY! All you have to do is email us a pledge amount and your mailing address information. You can choose to pledge per species (ex. 50 cents/species= $50 if we see 100 species) or pledge a fixed amount. After the birdathon, we will contact you for your pledge money, and you will recieve a written account of our day, a species list, and information on our summer owl project. Anyone who donates over $100 will also receive a juvenile Saw-whet adoption package, including a photo of your owl, banding information, and an adoption certificate. Last year's birdathon raised $1,500 for the summer owl research. That money contributed significantly towards funding this new project. We had a great response from those who attended this year's Spring Fling, thanks to all of you who have already sponsored.

You can email us your pledge at: wpbostaff@gmail.com, or send it to:

WPBO-Birdathon
16914 N Whitefish Point Rd
Paradise, MI 49768

Thank You!

Our New Summer Owl Study

During the summer of 2006, WPBO conducted an exploratory owl banding research project at the Point. Our project ran 3 weeks, and our efforts resulted in the capture of 208 owls; 206 Northern Saw-whet Owls (NSWO) and 2 Long-eared Owls. Of the 206 NSWO captured, 200 were juvenile birds. While the spring and fall migrations of NSWO have become increasingly well studied across the continent, these results represent the first documentation of a significant concentration of juvenile NSWO during the post-breeding period.

Thanks in large part to generous donations made by two individuals and pledges to the spring staff birdathon, we have been able to continue and expand this study during the summer of 2007. We began on July 1st, and as of August 10th we have banded 542 owls; 539 NSWO and 3 Long-eared Owls. As in 2006, the majority of the NSWO we have banded this summer have been juveniles.

In addition to the regular data we collect on all owls, we are visually accessing fat stores and muscle mass on all of the juveniles. Among North American owls only NSWO and Boreal Owls have a juvenile plumage that is significantly different from adult plumage. The juveniles begin actively molting out of their juvenile plumage and into adult plumage during our study period. Detailed descriptions of the molt progression on each juvenile have been collected.

Owl banding Spring 2007

Several changes were made to the spring owl banding protocol in 2007. These changes were made in an effort to increase our captures, thereby increasing our data base and our knowledge of the owl migration at Whitefish Point. Owl banding data collected by WPBO during previous springs clearly demonstrated that the Saw-whet migration at Whitefish Point was already at its peak during the 1st week of April. Therefore, the start date of the spring owl research was moved up from the previous start date of April 1st to March 15th. Audiolure was also introduced to the spring owl research for the first time. Audiolure is simply the practice of broadcasting a recording of an owl's call to lure them into the research area. This is a technique implemented at every other owl migration banding site that we know of, and has been used during the fall season at Whitefish Point since the fall study began in 1993. It has been documented that this practice increases Saw-whet captures 5-10 fold.
This spring the calls of Northern Saw-whet and Boreal Owls were broadcast. As the data from previous seasons suggested would be the case, Boreals were at the bottom of their irruptive cycle and none were captured. We fully expect that Boreal Owl captures during the next irruption will increase significantly due to the use of audiolure. As for Saw-whets, the changes proved a huge success after just one season. We banded nearly 280 Saw-whets during March alone; the previous high for an entire spring season was 122. Our total captures for all owl species in March was 318, these results are also higher than the total captures of any previous spring season. The chart below demonstrates the effectiveness of the changes implemented in the spring of 2007.

General Information

Whitefish Point Bird Observatory (WPBO) conducts long-term owl migration studies in both spring and fall. WPBO began its oversight of the spring owl research at Whitefish Point (WP) in 1988, and began the fall study in 1993. A summer study was developed during the summer of 2006 when a dispersal of juvenile Northern Saw-whet Owls was discovered within the study area. These WPBO research projects have resulted in the banding of over 7,000 owls of eight species; Great Horned, Northern Hawk, Barred, Great Gray, Long-eared, Short-eared, Boreal, and Northern Saw-whet. This reasearch has established WP as one of the most diverse owl migration sites on the continent.

* Study periods:
Spring: March 15-May 31
Summer: currently July 1-August 31
Fall: September 15- October 31

**During the study periods nets are opened nightly, weather permitting , 1/2 hour after sunset and closed 1/2 hour before sunrise. Nets are not opened during periods of rain or high winds.

FAQs

Why do we band owls?
The owl banding project is the most effective way we have to monitor the number of owls migrating through Whitefish Point. For example, without the owl banding project just 3 Saw-whet Owls would have be documented in the spring of 2007. Through the owl banding project, 750 Saw-whets were banded and 32 that were already banded were caught. Without specific efforts to document the owl migration at Whitefish Point it would go virtually undetected. For more information on bird banding visit the Bird Banding Lab's website, which can be linked out of the WPBO website.

How do we catch and handle the owls?
All of the owls in our studies are captured in mist nets that are made specifically for bird banding. The mist nets we use are 12 meters long andabout 10 feet high. Due to the size difference between species that we catch two different mesh sizes are used. The nets are placed in openings among the trees at Whitefish Point. To help attract the owls into the netlanes audiolure is used. Audiolure is simply the broadcast of an owls call.In spring and fall both Saw-whet and Boreal Owl calls are broadcast, only saw-whet calls are broadcast in the summer. We do not wear gloves while getting extracting owls from the nets or during the banding and measuring proccess. Like many other things, these procedures are more difficult when wearing gloves. Extractions in particular are already difficult and would be virtually impossible while wearing heavy gloves. Yes, we do occasionally get bit or have the birds get us with their talons, and yes it does hurt. To band and weigh the owls they are placed in cans. This is the common practice when banding birds of prey and actually serves to calm the birds down.

What data do we collect?
Each owl is fitted with an individually numbered U.S. Geological Survey band. These bands are issued to federally licensed bird banders by the Bird Banding Lab in Maryland. The main measurments we collect are weight, tail and wing chord length. If the bird has flight feather molt, the molt pattern is recorded. These measurements and the molt patterns help us determine the age and sex of many of the owls that are captured. The data, including the band number is then submitted to the Bird Banding Lab for inclusion in their database.