To develop a robust statistical method for assessing bird damage to crops, particularly fruit

In order to estimate the economic impact of damage inflicted by birds the damage inflicted must be measured. This project addressed the need for a technique for a robust, repeatable and accurate damage assessment method, which to date has not been available, or which has been labour-intensive or inconvenient due to other pressures on labour at the time an assessment is needed. The methodology was developed using grapes as a model crop, but it could be used for other assessments such as crop forecasting, and by adjusting the sampling method other crops could equally well use it. The methodology is available in the form of a protocol which consists of a robust sampling design, aids to training of personnel in visual estimation of damage, calibration of estimates with calculation of a correction factor for the subjective element of the assessment, and final calculations of actual damage. Templates in excel accompany the protocol.The contribution of NZ Winegrowers, Lincoln University, and participating vineyards is gratefully acknowledged