This section is from the book "The Balance Of Nature And Modern Conditions Of Cultivation", by George Abbey. Also available from Amazon: The Balance Of Nature And Modern Conditions Of Cultivation.
These live solely upon insects, taking flies of all kinds and many species of gnats, small moths and beetles on the wing, and beetles and other insects upon the ground. The swarms of winged aphides that migrate from ligneous to herbaceous plants, and from one plant to another in early summer in woods to late September, afford a fine harvest for swallows, and the crane flies that fly over the marshes, fields, pastures and lawns towards the end of the summer, are eagerly seized by the swallows flying low. Harming no one, swallows should be strictly protected internationally, their slaughter in the South of Europe and everywhere interdicted, even as food, and above all for purposes of fashion. Probably every swallow worn as millinery represents a decrease of useful vegetation equal to the weight of the person wearing it, in consequence of damage inflicted by pests as result of its destruction, and it equally applies to the food furnished to the killer by the swallow, this being out of all proportion to the food that would be available were it allowed to live and render incalculable service to humanity.
Birds, eggs and free-breeding should be a national and international concern as regards protection, no interference with these being tolerated in any part of the world, not even by a sparrow, much less by a person for ladies' headgear.