Persistence pays in Starling control

Reducing Starling numbers on dairy farms is likely to be most effective when several control methods are used and extra effort is made before numbers get out of hand in the autumn, according to a study funded by DairyCo.

A review by Kingshay on the problem on 11 farms in Somerset and their views on the usefulness of various control methods was carried out last winter. The Somerset Levels sees particularly large numbers of Starlings because up to 9 million birds migrate there to roost for the winter months on its wetland, but other parts of the UK have similar problems, says south west DairyCo extension officer Chris Coxon. “It’s a particular problem on farms feeding maize, but with the benefits of maize to cow diets, stopping feeding maize is not a viable option.”

Kingshay’s Duncan Forbes explains that the study saw up to 50,000 birds on one farm on a single day, although 8000-20,000 was a more typical average. On a day with high bird numbers, their measurements suggest they could eat up to 12% of the ration put out for cows, costing £153 for 100 cows in lost production possible from that feed.

Evaluating the information received from farmers on controlling numbers, revealed some useful tips on control. “The more control measures in place, combined with greater diligence in their use, led to lower Starling numbers recorded,” says Mr Forbes.

“Anecdotal evidence suggests being persistent in the early autumn before bird numbers get out of hand will also help.”

While not practical on every farm, netting or sheeting down maize clamps was given a high rating in terms of effectiveness, as was netting buildings if it could be done completely. Humans’ chasing them off is also likely to have some success.

“It’s also likely to be worthwhile feeding twice a day or after dusk, because the birds are selective feeders this means they only have access to half the daily ration,” says Mr Forbes.

Not so highly rated, but offering some degree of usefulness were scarecrows, particularly inflatable ones which were moved regularly, and trained birds of prey.

“This was a short study to understand the problem, the feed losses incurred and review existing control measures farmers had tried,” says Mr Coxon. “DairyCo hopes further research starting this year will come up with even better advice for farmers on controlling Starlings effectively.”

The advantages and disadvantages of various control measures tried can be found in the full report available at www.dairyco.org.uk.

Starling facts

• Starlings are migrant birds, arriving in the UK from early autumn
• Their population has been in decline, but the reasons for this remain unclear
• Wetlands on the Somerset Levels are attractive and popular roosts
• They are habit forming, so early intervention may be beneficial
• Their natural, preferred diet is the grassland pest, leatherjackets
• Maize silage and concentrate feeds in mixed rations are an easy and tasty alternative
• They tend to arrive on dairy farms soon after dawn and leave just before dusk
• Birds can access buildings and clamps faces through the smallest of holes, so physically keeping them out is almost impossible and expensive.