Q24: Damage to grapes from bird predation is a serious problem for grape growers. The article "Experimental Method to Investigate and Monitor Bird Behavior and Damage to Vineyards" (Amer. J. of Enology and Viticulture, 2004: 288-291) reported on an experiment involving a bird-feeder table, time-lapse video, and artificial foods. Information was collected for two different bird species at both the experimental location and at a natural vineyard setting. Consider the following data on time (sec) spent on a single visit to the location.
\table[[Species,Location,n,
z
,SE mean],[Blackbirds,Exptl,65,13.4,2.05],[Blackbirds,Natural,50,9.7,1.76],[Silvereyes,Exptl,34,49.4,4.78],[Silvereyes,Natural,46,38.4,5.06]]