There are many and varied bird species that will infiltrate your crop. Specifically looking at grapes, in Orange NSW forty three vignerons, representing 595 ha of producing vineyards responded to a survey in 2000.
Although this data is 18 years old it is still the only relevant document available and we all know that bird control really hasn't come past the use of nets, gas guns and real guns.
During the season of 2000, the majority of vineyards experienced between 1 and 30 percent crop damage.
Some experienced zero damage and others experienced complete loss of production. There was an obvious increase in birds during the ripening season, taking into consideration many factors including migration, seasonal changes and natural food source abundance and lack there of, this information is crucial to how bird deterrent techniques are applied. A ‘prolonged ripening period’ and ‘adjacent trees and vegetation’ were deemed as features that increased bird damage.
FYI the Agrilaser is specifically programmed to point over at the tree line surrounding a crop, especially at Eucalypts which are the main perching, roosting and nesting for our main pests. Flowering gums are a favorite for Silvereyes.
Outside the grape ripening period the number of birds ranged from less than 10 up to 100 birds seen per day. During the grape ripening period the number of birds ranged from 11 up to 500 birds seen per day.
Silvereyes (also known as Wax-eye, White-eye, Grey-breasted white-eye, Ring-eye) were perceived to contribute almost 25% of total bird damage. Further, Silvereyes, Starlings, Pied Currawongs and Noisy friarbirds, combined, are believed to contribute approximately 75% of total bird damage. Bearing in mind that each property has a different composition of bird issues, Silvereyes are regarded as the number one threat to wine grape production, contributing almost one quarter (24.27%) of total bird damage.
Starlings only remove berries and Silvereyes only peck berries, and the majority of damage is a result of pecking, It is generally understood that most honeyeater species (feathery tongues) are peckers and others species, such as Starlings, Pied currawongs and Black faced cuckoo shrikes are berry removers. Non the less, peckers or takers, it is almost and weirdly acceptable that there are crop losses within the property.
Silvereyes are generalist feeders, favouring insects, nectar and fruit. Extremely large flocks can arrive at feeding sites. For example, 20,000 silvereyes have been shot in a single orchard during a growing season. Although flock sizes vary with latitude, largest flocks usually occur following the influx of juvenile birds after January (when ripening is upon you).
So, the best way to future plan is to have your Autonomic in place well before ripening. As the saying goes "the early bird catches the worm"