A STARLING CONTROL PROGRAM FOR THE OKANAGAN SIMILKAMEEN
BACKGROUND & INTRODUCTION TO BRITISH COLUMBIA
In 1890 The American Acclimatization Society brought 60 European Starlings (Sturnus vulgaris) to Central Park in New York City in order to be one step closer in achieving their goal to establish all of the birds featured in Shakespeare’s plays into North America. A further 40 Starlings were introduced in 1891. This species is now firmly established across the entire continent and are one of the most common and widespread birds in North America. Starlings are listed on the World Conservation union List of the World’s 100 Worst Invasive Species.
First sightings of Starlings in the Okanagan Valley were reported in Oliver in 1945. First nests were discovered in Vernon in 1952. It is believed that starlings became a successful breeding species in the Okanagan sometime between 1952 and 1956.
Starlings are intelligent and adaptable birds. They exist in almost all habitat types but are most commonly associated with human habitations. Starlings form large flocks in early fall and can be seen flying from roost to field in great numbers. They may fly 30 or more miles from roosting to feeding sites. Flocking is beneficial to individual birds because more time can be spent foraging for food rather than looking out for predators.
In addition to eating and damaging tree fruit, grape and berry crops, starlings also spread diseases such as Salmonellosis, Chlamydiosis, Johne’s Disease, avian tuberculosis and histoplasmosis. Starlings are very aggressive competitors and are relentless in taking over nesting cavities that would otherwise be used by bluebirds and other native songbirds. They will take any suitable site for nesting and evict any previous owner; driving native birds from their territory. They sometimes watch other birds build a complete nest before forcing them to leave. Starlings have two broods a year with four to five eggs in a brood. They average 8 offspring per year. Incubation of the eggs takes 12 days and the fledglings leave the nest after 25 days. The young leave to join other juveniles and form flocks that move on to other territories.
Noise deterrents, such as propane cannons or electronic distress calls, and visual repellents such as reflective tape, have been used to frighten starlings away, but these birds are so tenacious that they quickly learn to ignore noise and visual scare tactics. Additionally, noise devices increase potential neighbor conflicts. Netting of fields can be effective in preventing crop loss, but it is expensive and it isn’t practical for tree fruits.
Some producers hire commercial falconers to assist in the control of starlings in their vineyards and orchards. This is labour intensive and very costly. Native raptor species can be effective in directly preying, or chasing starlings, but consistent presence is difficult to guarantee.
Starlings cause an estimated $800 million in damage to agricultural crops in N. America annually with conservative estimates of damage to vineyards and tree fruits in the Okanagan Similkameen placed at over $4 million annually.
WHY STARLINGS ARE CONSIDERED TO BE PESTS
Starlings are considered to be pests because of the damage they cause, especially to agriculture and in urban roosts.
Starlings are well adapted to urban life, which offers an abundance of nesting & roosting sites. Large flocks are unsightly, noisy and contaminate the area with their droppings.
At livestock operations starlings consume feed and contaminate the feed and water with their droppings. They are particularly attracted to these locations in the winter when the weather is cold and food is scarce. Starlings may also transfer disease among livestock facilities. In winter, flocks of up to 2000 birds can consume 1 to 2 tonnes of feed in a month and can contaminate or spoil an additional 500 to 1000 kg of feed. They also selectively eat the high-protein portion of protein-supplemented livestock feed.
Berry, tree fruit and vineyard operations are a favourite target for these flocks of birds, consuming and/or damaging fruit in quantities that add up to significant losses to farmers and to the local economy.
ACTIVITIES OF THE STARLING CONTROL PROGRAM
A pilot Starling Control Project aimed at reducing starling populations through an aggressive trapping program began in 2003. Various agricultural commodity organizations, environmental funding programs and Regional Districts funded this project. The BC Fruit Growers’ Association provided administration for the program. This pilot project met with particular success in Keremeos and in parts of Oliver and Osoyoos where a more intensive trapping effort took place. The project wrapped up in early 2006 however there were many supporters of the program who were not prepared to see the program’s demise.
With the experience gained from the pilot project, the agriculture commodity groups proposed to take the program to a larger, more intense approach throughout the Okanagan-Similkameen. This group also recognized that in order to evaluate the effectiveness of the trapping program, more information was needed on the structure of the starling populations in British Columbia. With those two issues in mind, the program’s management committee worked to secure funding with the three regional districts in the Okanagan Similkameen. At the same time, a research component was added to determine the origins of the starlings in the Okanagan & Similkameen valleys in order to focus the trapping efforts in the most effective manner and to improve other starling control measures.
This research was under the direction of Dr. Tom Dickinson of Thompson Rivers University (Kamloops). An arrangement was made between Thompson Rivers University and the University of British Columbia Okanagan (UBCO) for the work to be carried out at UBCO by graduate student, Jessi Neuhauser under the direction of Dr. Jeff Curtis.
The research program was funded through an Industrial Post-Graduate Scholarship from the National Science & Engineering Council of Canada (NSERC) as well as partnerships between the two campuses and support from the Agriculture Environment & Wildlife Fund through the British Columbia Agriculture Council.
THE TRAPPING PROGRAM
A team of professional trappers who use ethical and humane practices carries out trapping. Trapping is most successful in feedlots and other cattle operations. Once trapped, the birds are moved to an enclosed box and euthanized using CO2. The carcasses are available for distribution to bird rehab centres and falconries and the remainder are composted.
A team of trappers cover each of the 3 funding Regional Districts.