ALLIANCE BETWEEN BARN SWALLOW HIRUNDO RUSTICA LINNAEUS, 1758 AND INDIAN MUSTARD BRASSICA JUNCEA (L.) CZERNAJEW, 1859: A NEW INTUITION IN BIRD-PLANT ECOLOGICAL NETWORKS

Abstract

The habitat type and food availability always influence the population size of many
organisms. Bird’s feeding pattern should be abstracted to complete avian community structure
data. The agronomy main research farm of Orissa University of Agriculture and Technology
is a well-managed multi-crop agro-ecosystem which provides a suitable ground for ecological
research. In a multi-crop farmland, the association of Barn Swallow Hirundo rustica Linnaeus,
1758, with the Indian mustard Brassica juncea (L.) Czernajew, 1859 crops have been
recorded for the first time while hovering only on this field. A flock of Barn swallows was
recorded in 32 field visits while flying continuously over the Indian mustard field after
flowering to ripening of fruit in the morning and sometimes in afternoon also. The range of
the birds was recorded from 6 to 61 with a mean individual of 36.03 ± 15.37 hovering for
1.83 hr daily. This may be the behaviour for the feeding pattern of these flying insectivorous
birds which was not seen in other crop-fields with same insect diversity describing it as not
the only reason for this behaviour. To reveal this poorly understood behaviour of flying
insectivore birds, a detailed long term behavioural study with gut content analysis is needed to
explain the particular reason behind this behaviour of Barn swallows which will support the
conservation of these birds and control their population decline.