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RESEARCH| With its massive concentrations of birds, Whitefish Point ranks among the most significant avian migration sites in North America. The Observatory's research programs are built around the vast biological opportunities of Whitefish Point and the northern Great Lakes ecosystem. The Whitefish Point Bird Observatory conducts a diurnal raptor census, a nocturnal raptor census, a waterbird census, and a daily estimated total of all migrants moving through Whitefish Point. Below are the details of each research program.
OWL RESEARCH |
Lewis Woodpecker,
Spring 2003 |
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DIURNAL RAPTOR CENSUS
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| Whitefish
Point is a phenomenal concentration spot for migrating
owls during both spring and fall. Owls observed at
the Point include Northern Saw-whet (NSWO), Boreal (BOOW),
Long-eared (LEOW), Short-eared (SEOW), Great-Horned (GHOW),
Great Gray (GGOW), and Northern Hawk Owl (NHOW).
Ongoing owl banding research programs are conducted by
the WPBO in spring, summer and fall. The object of this
research is to monitor owl populations over time, and to
gain a better understanding of how these populations
fluctuate and change over the years. This program also
gathers valuable data on little known owls such as
Boreals and Great Grays.
Help support our summer owl research . Download, print, fill out and print form. We need assistance with nest boxes, as well as donations. Owl Banding ProjectThe spring owl banding has run annually since 1988, from 1 April to 31 May. Nets are operated every night (weather permitting). Note: As of 2007, the spring owl banding program has implemented audiolure to increase capture rates. This increases sample size and generates a larger database to use in our research efforts. The start date changed to 15 March, since it has been found that owls (specifically Northern Saw-whets) are migrating during this time period. See WPBO spring owl banding season totals. The fall owl banding has run annually since 1993, from 15 September to 31 October. The fall program uses 2 audiolure sites; a NSWO caller and a BOOW caller. These calls are broadcast to lure the owls into the nets, thus increasing capture rate and sample size. Additionally, passive nets that are not associated with a lure are used. Nets are operated every night (weather permitting). |
Juvenile Northern Saw-whet Owl by Chris Neri |
Juvenile Northern Saw-whet Owl Dispersal
During the summer of 2006, WPBO conducted an exploratory research study to determine if there were juvenile Saw-whet owls dispersing through the Whitefish Point area. Our efforts resulted in banding 200 juvenile Saw-whets in three weeks during July and August.
While the spring and fall migrations of Saw-whets have been well studied both at Whitefish Point and throughout the continent, this exploratory study represents the first ever documentation of an incursion of juvenile Saw-whets during the post-breeding period.
A juvenile Saw-whet is easy to tell from an adult because it has a completely different plumage. When the juveniles leave the nest, they have a dark facial disk and a buffy chest. It may take up to several months for them to molt into the full adult plumage.
Because Saw-whet owl dispersal in these quantities has never been documented before, we are continuing this research during summer 2007, and hope to target a few specific questions in order to learn more about these owls and their summer movements. Our current projects include taking blood samples for DNA analysis, and putting up nest boxes to determine how many Saw-whets are nesting in this area.
Nest Box Project
One key question that arises with this research study is whether or not we have a large local breeding population of Saw-whets. The answer to this question will help us determine how many of the juvenile birds we capture in the summer are local vs. dispersing from other areas. Saw-whets tend to nest in old woodpecker cavities. We plan to put up nest boxes, which simulate a cavity, but are much easier to check and manage each year. In order to do this, we need funding for lumber and/or donations of lumber from local mills. We also need local volunteers to let us put nest boxes on their property. Having breeding owls in your backyard is not only good for owls, but will also help decrease your mouse population!
DNA Analysis
The current method for determining the sex of Saw-whets uses a discriminant function chart that combines the wing measurement and weight. This function was developed by using DNA analysis on a huge sample of Saw-whets. To help eliminate any regional or seasonal biases, samples from across the continent and in all seasons were used to compile this database. However, the sample birds did not include juveniles. We have found this function for sexing Saw-whets to be less reliable for our juveniles. Our summer research provides the first opportunity to collect DNA samples from juvenile birds during the post-breeding period for incorporation into this analysis. The cost is about $20 per bird. Our goal is for a sample size of 100 juvenile owls.
WPBO spring owl banding season totals
|
1988 |
1989 |
1990 |
1991 |
1992 |
1993 |
1994 |
1995 |
1996 |
1997 |
|
|
NSWO |
59 |
43 |
46 |
62 |
49 |
47 |
19 |
74 |
40 |
15 |
|
BOOW |
163 |
16 |
1 |
15 |
114 |
8 |
0 |
3 |
57 |
73 |
|
LEOW |
36 |
11 |
22 |
48 |
34 |
29 |
9 |
172 |
12 |
4 |
|
BDOW |
7 |
7 |
5 |
12 |
6 |
2 |
5 |
3 |
5 |
0 |
|
GGOW |
0 |
2 |
2 |
1 |
5 |
1 |
0 |
0 |
12 |
5 |
|
GHOW |
1 |
2 |
1 |
4 |
0 |
0 |
0 |
0 |
1 |
0 |
|
NHOW |
0 |
0 |
0 |
0 |
1 |
1 |
0 |
0 |
0 |
0 |
|
SEOW |
0 |
0 |
0 |
1 |
0 |
0 |
0 |
0 |
0 |
0 |
|
1998 |
1999 |
2000 |
2001 |
2002 |
2003 |
2004 |
2005 |
2006 |
|
|
NSWO |
122 |
81 |
114 |
104 |
29 |
35 |
91 |
95 |
66 |
|
BOOW |
0 |
0 |
8 |
64 |
0 |
0 |
11 |
73 |
49 |
|
LEOW |
24 |
162 |
28 |
27 |
44 |
83 |
83 |
31 |
33 |
|
BDOW |
17 |
2 |
5 |
10 |
2 |
2 |
10 |
7 |
8 |
|
GGOW |
5 |
1 |
0 |
2 |
1 |
0 |
0 |
14 |
5 |
|
GHOW |
0 |
0 |
0 |
0 |
0 |
0 |
0 |
1 |
0 |
|
NHOW |
0 |
0 |
2 |
0 |
0 |
0 |
0 |
1 |
0 |
|
SEOW |
0 |
0 |
0 |
0 |
0 |
0 |
0 |
0 |
0 |
WPBO fall owl banding season totals
|
1993 |
1994 |
1995 |
1996 |
1997 |
1998 |
1999 |
2000 |
2001 |
|
|
NSWO |
38 |
168 |
183 |
54 |
170 |
190 |
244 |
83 |
186 |
|
BOOW |
0 |
5 |
26 |
170 |
2 |
2 |
1 |
159 |
3 |
|
LEOW |
0 |
2 |
4 |
1 |
1 |
7 |
3 |
0 |
6 |
|
BDOW |
5 |
1 |
4 |
1 |
16 |
3 |
8 |
4 |
3 |
|
GGOW |
1 |
0 |
0 |
0 |
2 |
0 |
0 |
0 |
1 |
|
GHOW |
0 |
0 |
0 |
0 |
0 |
0 |
0 |
1 |
0 |
|
NHOW |
0 |
0 |
0 |
1 |
0 |
0 |
0 |
0 |
0 |
|
SEOW |
0 |
0 |
0 |
0 |
0 |
0 |
0 |
0 |
0 |
|
1993 |
2002 |
2003 |
2004 |
2005 |
2006 |
|
|
NSWO |
38 |
71 |
163 |
177 |
183 |
339 |
|
BOOW |
0 |
0 |
0 |
42 |
21 |
0 |
|
LEOW |
0 |
4 |
3 |
2 |
3 |
15 |
|
BDOW |
5 |
2 |
18 |
9 |
10 |
4 |
|
GGOW |
1 |
0 |
0 |
0 |
0 |
0 |
|
GHOW |
0 |
0 |
0 |
0 |
0 |
0 |
|
NHOW |
0 |
0 |
0 |
0 |
0 |
0 |
|
SEOW |
0 |
0 |
0 |
0 |
0 |
0 |
* information updated by Nova Mackentley
WATERBIRDS
Whitefish Point is the most important spot for documenting and monitoring waterbird movements in the upper Great Lakes. Spring and fall counts record loons, grebes, ducks, geese, shorebirds and other waterbirds, providing important information on abundance and timing of migration, aiding in regional and international efforts to monitor changes in populations. Before WPBO started documenting the waterbird migration at Whitefish Point, certain species such as red-throated loons, scoters and red-necked grebes, were considered uncommon in Michigan. Spring Jaeger records were unheard of anywhere in the upper Great Lakes until the first documented occurrences at Whitefish Point.
Unlike the hawk count the hawk count, the waterbird count is conducted in both research seasons. The spring count commences on April 15th and runs to May 31, and August 15 to November 15, although in some years it has been extended. In both cases, it is conducted from the beach near the tip of the Point about 50 yards from the shore. The exact location varies slightly as the beach changes due to erosion. The count begins at sunrise and continues for 8 hours.
Counting waterbirds is rather straightforward in comparison to counting other birds at Whitefish Point. Waterbirds tend to migrate directly and rarely linger like so many hawks and songbirds. There are exception including shorebirds, red-breasted merganser, ring-billed gulls, and herring gulls, some grebes, and some loons. Regardless, most birds tend to migrate from southeast to northwest in spring and the opposite direction in the fall. Therefore, any birds seen migrating in the appropriate direction are counted. Individuals are not subtracted from the count if migrating in the wrong direction.
The goal of the census is to quantify the chronology and volume of migrating waterbirds in the Whitefish Point Migratory Corridor. Interpreting the waterbird data, like all bird censuses, must be done in the long term. Unlike the hawk count, in which weather can have tremendous effect on the ability of the birds to reach the Point, visibility is the prime concern during waterbird counts. Some of the most inclement days have had some of the highest numbers of migrating waterbirds, but if it is foggy the ability to detect the passing migrants is impossible.
SONGBIRDS
Daily Estimated Totals
One of the first things birders learn when visiting Whitefish Point is that counting birds can be difficult. There are just too many of them, and they act in an erratic pattern, moving incessantly about the Point.
Scarlet Tananger By Ken Jacobsen, Jr.
The difficulty of devising a DET methodology for WPBO is deciding which species are migrating and which are lingering. Two basic methods are used to determine a species DET. This methodology is very similar to the method used to count migrating hawks. Species such as chickadees, blue jays, and evening grosbeaks, which tend to linger at the Point, are recorded only as the maximum totals seen at one time for that individual species. Other species such as American Robins which tend to pass directly through the Point are individually counted.
The goal of the DET is to quantify the chronology and volume of the bird migration at the Point. Interpreting the DET is not easy. Bird migration at the Point has many variables, such as weather, that complicate our data analysis. In addition, this methodology is not designed to count all individual birds, which would be impossible. Instead, it is designed to count species and their totals each year, in order to provide data on long term population trends.
Canadian Migration Monitoring Network
Whitefish Point Bird Observatory is the only US based bird observatory in the Canadian Migration Monitoring Network. This network of observatories operates studies across the continent, from the Atlantic to the Pacific, tracking the numbers and movements of migrating birds. Each of these stations share and process enormous volumes of data, painting the "big picture" of what bird populations are doing across the northern half of North America.
The network is supported by Bird Studies Canada, but involves the cooperation of many bird observatories. Bird Studies Canada is developing standards for data collection, preparing computer software to aid with data entry for migration counts, and developing analysis programs to calculate trends automatically using the data from each station. Whitefish Point