This project is designed to determine wintering populations of the various species of birds of prey throughout the state of Oregon. Through a collection of preapproved survey routes established in all parts of the state, volunteers completing the once a month surveys from December through March will count the various species that they find and report their findings to the project coordinator.
A survey protocol has been developed to assist the volunteers with collecting the data. It describes how to go about doing a survey, when best to do them, and what to watch out for that might adversely effect their efforts. The protocol is designed to have all of the volunteers attempt to use a standard surveying procedure so that differences can be kept to a minimum.
Volunteers will play an integral part in determining their survey routes. A proposed route will be provided by the project coordinator during the route development stage. The volunteer will then have the opportunity to fine tune the suggested route based on their local knowledge of the area to be surveyed in order to maximize bird numbers observed for their time spent conducting the survey. They will be able to adjust the route size to meet their time restrictions for completing the surveys.
Volunteers are required to provide their own transportation while conducting the surveys. Driving safety is the number one priority so volunteers are instructed not to take unnecessary risks during the surveys. ECAS will not be held accountable for vehicle related or volunteer induced problems that may arise during a survey. Once surveys are completed, data collected will be passed on to the project coordinator via preapproved data collection forms. These forms are designed specifically for each survey route. Data can be transmitted via email through computer or by using the regular mail service.
Volunteers should have good raptor identification skills and be able to have the ability to locate birds while physically driving their survey route. A functional pair of binoculars is mandatory. A spotting scope can be of additional help for identifying birds at long range but is not mandatory to have. Volunteers can conduct these surveys by themselves or with the help of friends and/or family. If driving and looking for birds at the same time is a physical problem, volunteers are encouraged to bring someone else along to help spot birds or to just enjoy the experience with them.
Results and News in Dec 2010
The sixth season of survey work for the East Cascades Audubon Society’s statewide Winter Raptor Survey Project got underway full force the beginning of December. Nearly half of the 134 routes in the project this winter were surveyed during November but the main thrust of this project is surveys during December through February. Some routes will also be covered during March. Last year we had 129 routes in the project. We welcome the new routes this winter: Ridgefield NWR and Butte Valley which are located in WA and CA respectively just over the OR border, Little Valley-Harper and Juntura which are along Hwy 20 between Burns and Ontario, and Alsea which is along Hwy 34 between Corvallis and Waldport.
A total of 106 routes were surveyed during December and it became clearly evident from the results that this was going to be a good year for raptors. The main indicator was the increased number of Red-tailed Hawks, the primary raptor species in this project. Not since December 06 have we seen the numbers of this species that we have found thus far. In December 08, a total of 94 of 126 routes and 7040.8 miles were surveyed. A total of 5,698 total raptors and 2,723 Red-tails were found. Birds per mile density were 0.80 and 0.39 respectively. This December, a total of 106 of 134 routes and 7962.5 miles were surveyed. A total of 7,890 total raptors and 4,004 Red-tails were found. Birds per mile density were 0.99 and 0.51 respectively, both considerable increases over last winter.
For this project, the state is divided into 10 regions. Six of the 10 regions experienced increases in Red-tailed Hawk populations with the biggest increases found in the Central, South Central, and Northeast portions of the state. Red-tails per mile in these 3 areas were 0.64, 0.76, and 0.80 respectively and represented increases of 0.12, 0.37, and 0.20 birds per mile respectively from last winter. These three areas, along with the Willamette Valley region, also had the highest total raptors per mile, all 4 exceeding 1.00. A total of 46 of the 106 routes surveyed exceeded 1.00 total birds per mile.
The 6 routes with over 100 Red-tailed Hawks included Milton-Freewater (239), Baker Valley (203), Klamath Basin South (155), Linn County Unit 3 (121), Butte Valley (CA) (119), and Linn County Unit 4 (104). Together, these routes accounted for 24% of all Red-tails counted this month. The Milton-Freewater route has produced more than 200 Red-tails eight times. The real surprise so far this winter has been the numbers found on the Baker Valley route. In November, a total of 229 were found. Prior to this winter, the highest single survey count was 119 found in March 09 and the average for 23 previous surveys before March 09 was 63 birds. It appears that conditions are pretty good right now in the Baker Valley for Red-tailed Hawks J A total of 25 routes (24%) this month recorded new December highs or new total Red-tailed highs overall. A total of 15 of these 25 routes were located in the above mentioned 3 regions.
As in past winters, the top 5 species found on the December surveys were Red-tailed Hawks, American Kestrels, Northern Harriers, Rough-legged Hawks, and Bald Eagles. Their respective percentages of the total number of raptors found for each of these species was 51, 20, 08, 07, and 05. Together they accounted for 91 % of the total, pretty much the monthly average over the last five winters for these 5 species. The remaining 9% of all raptors counted in December were made up of 18 other species. By far the most welcome species this month was the Gyrfalcon. Single birds were found on the Enterprise and Lower Columbia River routes. In November, one was also found on the Curry County South route. Equally of interest was a single Osprey found on the Richland route in far eastern Oregon. A notable miss was the Snowy Owl that took up residence along the north coast located along the Tillamook West route. We are hoping to catch it out in the open on a future survey to include it in this winters results J
As has been stated many times in the past, this projects success rests squarely on the shoulders of the very dedicated cadre of volunteers that conduct the surveys. I greatly appreciate all of their efforts to make this project what it is! We all have a great love of these special birds and through our collective efforts we get to see how important the state of Oregon really is in the lives of these birds. The more we know about their numbers and distribution, the more we might be able to make their lives a little bit more comfortable during the most difficult months of their lives. I am looking forward to seeing what the rest of this winter has in store for these birds and I want to thank everyone who is helping with this effort!
The first formal presentation of project results was given to the Roseburg Audubon Society chapter in November. A power point presentation of raptor photos and various charts was used to explain how the project works, species that have been seen during survey work, and results of the work that has been done over the first five winters of the project. Twelve chapter members were present and the presentation was well received. I had a good time with this effort :)
The project has been expanded this winter with the addition of at least 5 new routes, with 2 additional routes in the works that will start up in January. Two of the new routes are located in WA and CA just across the Oregon border from existing project routes. This expansion is an experiment to see if we can successfully move into neighboring states for future raptor monitoring. Priority for this expansion will be limited to areas immediately adjacent to the Oregon border so as to dovetail with Oregon raptor populations at a geographical level not limited to politically established boundaries. Contact has been made with additional folks interested in pursuing other WA locations along the Columbia River in the central Oregon area for the 2010-11 survey season.
An effort is underway to statistically analyze the results of the first five winters of the project. In addition to this analysis work, work is going to commence to prepare an article about the project and its results for publication in a professional journal to be selected at a future date. If this is accomplished, an effort will be made to pursue future program presentations to whatever organizations that express interest in project information.