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Bird Species Causing Damage 



Bird species causing damage to the cultivated blueberry crop are 

 mostly songbirds, including robins, Baltimore orioles, bluejays, cat- 

 birds, towhees and sparrows; and blackbirds including starlings and 

 grackles (5,6). Although species causing the damage varies consider- 

 ably with the area because of behavior patterns, surrounding habitat 

 and food preferences. Smith (8) in 1963, reported that robins were one 

 of the greatest problem species. 



Starlings are the main depredating species in lowbush blueberries 

 in Massachusetts. 



Extent of Damage 



A substantial crop loss occurs each year in non-covered cultivated 

 blueberry plantings. By questionaire and personal contact, it was de- 

 termined that crop losses in cultivated blueberries for the years 1955- 

 1958 were 38 per cent, 20 per cent, 19 per cent and 27 per cent, respec- 

 tively (5). A survey was again conducted by Smith (7,8) in 1960 and 

 1961. Based on a M-1 per cent questionnaire return, 27 per cent of the 

 fruit on 310 acres of cultivated blueberries in Massachusetts were lost 

 to birds in 1960. A 37 per cent crop loss occurred on 121 acres reported 

 in 1961. 



No known survey of bird damage to lowbush blueberries in Massachu- 

 setts has been conducted. 



Control Methods 



Numerous bird damage prevention devices have been used by growers 

 and tested by graduate students working on the bird control project. 

 To date, however, the only totally effective method of preventing bird 

 depredation is by complete enclosure of the planting. Although many of 

 the larger growers still rely on firecrackers and exploders, those with 

 limited acreages now are covering their plantings. 



Nettings of various types are available for exclusion of birds from 

 blueberry plantings; many of which we have field tested: tobacco cloth, 

 used fish net, kraft paper yarn, nylon, polyethylene and acrylic webbing. 



A netting must be durable, economical and easy to handle. Large 

 dimensions also are a desirable feature. Tobacco cloth lacks durabil- 

 ity and tensile strength. The polyethylene net tested (7/15" or 1" mesh) 

 lacked tensile strength and its use was abandoned after one year's test. 

 The net with 7/16" mesh, however, would be of value for protection of 

 strawberries against bird depredation because generally no framework is 

 built over the plants. Some of the nettings require considerable sewing 

 together at the initial installation due to their small width; for ox- 

 ample, kraft paper yarn and nylon. Used cotton fish netting, which is 

 sold by the pound, has small holes that must be patched and is difficult 

 to handle in comparison to nylon net. Although we have not field-tested 

 the net, nylon fish net now is available. The main advantages of fish 

 netting are low initial cost, tensile strength and large dimensions. 



