Bird Research Update - June 2008

To:  Whatcom, Skagit, and B.C. berry growers
From: Karen Steensma, Trinity Western University (TWU) and Steensma Dairy

Most of you are at least aware of, if not actively participating in, our ongoing research projects related to bird control in agriculture.  Thank you for your enthusiastic support of this important work!  This is an update explaining the various facets of the research to date, along with some measures you should be considering in the next few weeks.

I. Kestrel nest project.  In 2007 we placed 10 nest boxes to attract kestrel falcons on Axling Road near Lynden.  Kestrels, the smallest native falcon species in our area, are highly territorial and will chase starlings and other birds away, while also preying on small birds (including starlings), rodents, and large insects.  They have been used successfully to reduce and/or eliminate bird damage in Eastern Washington cherry orchards.  Their natural cavity-nesting habitat (old trees and snags adjacent to open meadows) has disappeared in Western Washington, making them rarer here.

TWU student Katherine Hartline and volunteer biologist Dave Timmer of A Rocha USA (a Christian conservation organization) both contributed to this effort by placing, monitoring, and maintaining the 10 boxes over the nesting season.  At least one kestrel was seen, with anecdotal evidence of fewer starlings feeding on area dairy silage.

This year we have placed boxes and/or begun monitoring boxes placed directly by growers at over 50 locations in Whatcom and Skagit counties.  This work was again accomplished with volunteer efforts, with biologist and A Rocha intern Becky Kern monitoring the boxes and contacting growers through April.  Kestrels were spotted near boxes at Steensma Dairy, Enfield Farms and Sakuma Brothers thus far in 2008.

A jointly funded $4,000 grant from local farmers coordinated by Whatcom Farm Friends and the BC Blueberry Council was obtained beginning in May to allow more detailed kestrel enhancement work through the intensive spring nesting season.  TWU successfully applied for a scientific research permit from the Washington State Department of Fish and Wildlife, to transport orphaned kestrels found elsewhere in the state to Whatcom County for rehabilitation and release.  The goal is to increase the kestrel population more rapidly by providing these "immigrant" birds as a jumpstart. Katherine has been employed under this funding, and has continued monitoring boxes, begun mapping box locations, and has conducted orphan release and tracking.

To date, two kestrels have been released locally.  Early this month we received our first orphan, a female from the Yakima area.  She spent several days in captivity with master falconer Dan Pike, and was subsequently released for her fledgling flight near Axling Road.  She flew well, was tracked closely for approximately 48 hours, and remains in the Jackman and Axling Road area. It is hoped that she will find one of the single male kestrels already known to be in the area and nest here next year.  A male kestrel from Quincy, released mid-June, was last seen north of Lynden. Further orphan kestrels are expected through early- to mid-summer.  Long-term data collection on the success of the boxes and the released orphans, as well as land-use patterns surrounding the boxes, will be helpful in determining which areas provide the best habitat to support these birds.  An ultimate goal is to provide management techniques to area farmers who wish to increase their chances of supporting these helpful birds of prey while also decreasing bird damage.

II. Starling behavior project.  TWU recently received a $20,000 grant from the British Columbia Ministry of Agriculture and the Fraser Valley Regional District to monitor starling populations in agricultural areas east of Abbotsford.  The goal is to establish initial population numbers on the starlings, experimentally introduce deterrent techniques, and then measure the effectiveness of the various techniques.

This pilot project work has begun with three TWU biology and environmental studies students this summer, along with an A Rocha Canada intern.  Comparative effectiveness of propane cannons, taped distress/raptor calls, and hawk kites/balloons should provide growers with tools in making management decisions for bird control on their land.

Bird control measures you can take this summer.  Our extensive literature research and ongoing field research lead us to make the following preliminary recommendations for the current season:

• Encourage kestrels and other birds of prey by minimizing use of insecticides and rodenticides where possible, by leaving trees and snags around edges of fields, and by placing nest boxes for kestrels. Contact Steensma@twu.ca if you suspect a kestrel in your area or would like to place a box
• Monitor and clean out any kestrel boxes on your property so that starlings do not fledge from them. This should be done every 3-4 weeks through August. Any fledgling-sized starlings found can serve as food for orphaned kestrels - contact us for further information or assistance with this work.
• Emphasize hawk kites in combination with audiotapes, changing location frequently so that starlings do not become accustomed to predictable patterns. Randomness in times and frequency are more labor intensive, but much more effective. Consider dedicating part of your workforce to this effort.
• If propane cannons are used, change their location and timing frequently. Published research indicates that cannons are less effective than either natural predators or false predators (such as hawk tapes or distress calls), and effectiveness dwindles further with regular, predictable use.

Future direction.  It is expected that the above recommendations will continue to be refined and improved over time. Much more research is needed to promote helpful predators while also maximizing the profitability of farm operations.  Let us know your ideas and whether you are willing to participate in research trials in the future!

Partners/Sponsors: Maberry Packing, Curt Maberry Farms, Enfield Farms, Sakuma Brothers, Rader Farms, Mike VanWingerden, Steensma Dairy, Jeff Littlejohn, Whatcom Farm Friends, BC Ministry of Agriculture, Fraser Valley Regional District, Washington Dept. of Fish & Wildlife, A Rocha, TWU, WSU Cooperative Extension 

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