Modern agriculture, whose development has been driven by the goal of increasing productivity and meeting the growing need for food and textile fibres, has led to considerable simplification of cropping systems in terms of the diversity of the species grown and cultural practices in agricultural landscapes (Altieri, 1999; Altieri and Nicholls, 2004). Today, agricultural environments are the most striking example of the consequences of the massive loss of biodiversity (Altieri and Nicholls, 2004). In Canada, the development of intensive agriculture has been accompanied by the steady loss of natural habitats. More than half of the wetlands in southern Canada have been lost, 70% of which were located in southern Ontario (Mineau and McLaughlin, 1996).