Barn Swallow

Barn Swallow - Widely Distributed

Barn Swallow

The Barn Swallow (Hirundo rustica) used to be one of our most common swallows.  Along with the Tree Swallow we saw them every day in summer flying over fields and other agricultural land.  Recently there has been a huge decline in insectivorous birds including swallows.  We have to search now to see Barn Swallows.  

Barn Swallows are our most widely distributed swallow species.  They are found in summer over most of North America from the tree line southward to Mexico.  They spend their winters in South America with their winter range extending as far south as central Chile and northern Argentina.  Barn Swallows are tremendous fliers and some migrants actually take trans-oceanic routes.  

Barn Swallow - Male and Female

Barn Swallows prefer fields and open areas near water.  They nest in man-made structures like barns and sheds but also bridges.  Areas near water are preferred so that there is an abundance of aerial insects.  I am sure we can all remember the sounds of nesting Barn Swallows as we entered a barn years ago.  It is sad that that is no longer true.  Not all agricultural structures now have nesting Barn Swallows.   For many years we had our regular nesting pairs in our barn which had a pond nearby.  We would often have 3 or 4 nesting pairs.  Upon entry into the barn one would hear the familiar chittering and ‘cheezie’ sound greeting us.  The Barn Swallow nest is made of mud mixed with their saliva and minimal grass fibre and it is usually placed on a beam or ledge high in the barn.  It was common to see the adults gathering mud from a puddle in the barnyard during nest building.  It has been shown that the male and female together make about 1000 trips to collect enough mud for the nest.  In the cup-shaped nest are laid 3-7 white eggs with brown spots which are incubated 13 to 17 days by both adults.  

Almost all modern Barn Swallows nest in man-made structures.  In former times they nested in caves and cliff faces.  I have seen an active Barn Swallow nest on a rocky ledge on the southern shore of Lake Ontario.  That was certainly an uncommon find.

Barn Swallow

Barn Swallows are beautiful and distinctive.  The males are a dark iridescent blue on the crown, back, rump and tail.  The face and throat are a deep rufous brown and the breast is a light orange.  The tail is deeply forked and there are white spots at the base of the tail.  The female is similar but lighter in colour and her tail is shorter and not as deeply forked.  The wings of both are very pointed making them capable of a distinctive low zigzag flight as they hawk for insects.     

Studies of Barn Swallow behaviour have shown that for mates females prefer males with the longest symmetrical tails.  This has undoubtedly led to the beautiful swallow tails we see.  The Barn Swallow has also been important in history.  In times past they were killed in huge numbers for their feathers.  The movement to stop this led to the founding of the Audubon Society and the Migratory Bird Treaty Act.  

The recent decline in their population is very troublesome.  The declines have been 90% in the last 40 years!  That is about as bad as one could imagine.  The causes are the steep decline in agriculture.  This has led to far fewer barns and the modern barns are not amenable to avian inhabitants.  They have no or fewer eaves and surfaces for nesting and usually do not allow avian entry.  Modern barns often do not have the mixture of animals in them that in past times was conducive to swallow habitat.  The crops grown now also affect the swallow populations.  Barn Swallows are aerial feeders and some of our modern crops do not have large populations of aerial insects over them.  And we can add to these bad situations the increased use of insecticides both here and in their wintering grounds and we have a very bleak situation for the Barn Swallow.  

I remember in the 2 or 3 years prior to the demise of the Barn Swallow population in our barn that I would find nestlings on the barn floor.  These were young birds that were not yet ready to fledge.  If we replaced them back into the nest (with great difficulty at such a height) they would be back on the floor the next day.  I believe these young birds either jumped out of the nest themselves or were pushed out because the nestlings were starving.  There were not enough insects to adequately feed the birds in the nest.  After 2 or 3 years of this behaviour, the Barn Swallows left our barn completely.  We no longer had them in our barn.  That was sad.  Our barn was over 100 years old and probably had Barn Swallows nesting in it for most of those years.  Now there were none.  Something was really wrong.  I suspect that story has been repeated over much of North America.  And so, we have a very serious decline in the population of this beautiful avian species.  We have lost one of our best controls of our insect populations around our homes and barnyards.