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Cliff Swallows Building Nests

5-19-15 cliff swallow 719You may have heard of “lining” bees – following one honeybee after another, tracking them to their honey-laden hive. Recently I lined Cliff Swallows. My initial observation was of several swallows on a mud flat in the middle of a river, loading their beaks with mud and taking flight, all in the same direction. Knowing that their nests are made of mud pellets (900-1,200 of them), I knew that they must be nesting somewhere in the vicinity. The length of time between their departure from and return to the mud flat was quite short, so I deduced that the distance they were carrying the mud and depositing it couldn’t be too great. After heading off in the direction that the swallows were flying, I eventually discovered the very beginning of a colony of Cliff Swallow nests under the eaves of a nearby barn.

The building of a nest requires not only finding a source of mud, but also ferrying lumps of it (in their beaks) back to the nest site many, many times. Once a source has been found, its location is made known to all members of the colony, and they all make use of it. Cliff Swallows belonging to the same colony not only use the same source of mud, but gather it together as a group, and return to work on their nests all at the same time. They work in roughly half-hour shifts, after which they all take a break and forage for insects for ten minutes or so before resuming work.

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15 responses

  1. Wow what a great picture! I love it.! Meeze


    May 19, 2015 at 8:44 am

  2. So interesting that they work together and rest together. And thanks for the tip that if I’m ever lucky enough to see swallows gathering mud I just might be lucky enough to see where they are building their nest. Love swallows!

    May 19, 2015 at 8:47 am

  3. Marilyn

    Is there any category for such communal creatures? Bees, ants, and such work together; sea birds often nest in colonies….

    May 19, 2015 at 9:28 am

    • Hi Marilyn,
      Insects that work cooperatively and live together (ants, bees, wasps, termites) are referred to as “social” insects. Birds that nest together (but don’t work together for the common good) are referred to as colonial nesters.

      May 19, 2015 at 11:47 am

  4. May and your readers, if you can help me out here??! Cliff swallows are different, I believe – ? – from barn swallows – ? Up here in Alberta, the cliff swallows turned up two weeks ago Thursday, and they largely seem to nest in a mass of what were built from the 1980s for American bluebirds. And, yes, some cliffs (!). My own barn swallows last year turned up three weeks after their relatives, and three pairs used the old red wooden barn here. So, I am now waiting for that crowd to turn up sometime later this week, I hope. Your thoughts – ?? Many thanks indeed.

    May 19, 2015 at 10:09 am

    • Yes, Pam Cliff and Barn are two different species of swallow. I’m not sure if that is what you are asking!

      May 19, 2015 at 11:41 am

    • Hi Pam,
      After reading Jean’s reply to you, I reread your comment, and I completely agree with Jean – those are probably Tree Swallows in your bluebird boxes! Tree Swallows nest in cavities or nest boxes, Cliff Swallows build s on vertical buildings or cliffs, etc. and Barn Swallows usually build in buildings, with nest sitting on substrate, not attached to a wall…

      May 20, 2015 at 6:56 am

  5. Once in the Canadian Arctic we stood on a cliff above a huge pool at the foot of a rapid, and could see big lake trout finning just below the surface. I tossed an apple-sized rock to scare them, but instead, they chased it down out of sight. Couldn’t figure out why, till we saw that the cliff was solid with swallows’ nests. Those fish were accustomed to tasty treats inside globs of dried mud – rather like polar bears and igloos.

    May 19, 2015 at 10:21 am

    • Willem, your tales provide my blog readers with delightful reading! Many thanks.

      May 19, 2015 at 11:39 am

  6. Fascinating observation and result, Mary. I should try this with the birds that are plucking animal fur from the net bag I hang in the tree in our yard.

    May 19, 2015 at 2:07 pm

  7. Jean Harrison

    To Pam: I am guessing that the swallows that nest in the bluebird houses are tree swallows. Tree swallows have no orange or buff colors, unlike barn swallows and cliff swallows.

    May 19, 2015 at 4:23 pm

  8. Cordelia Merritt

    Hi Mary – Just a quick thank you for how much your wonderful pictures and oh-so-literate prose make my life better. I head for your posts first. – even before my daughters. Gratefully and with much love Cordie

    May 19, 2015 at 9:55 pm

    • Your kind words mean so much, Cordie. You spur me onwards!

      May 20, 2015 at 6:53 am

  9. I have notice a fraction of the number of swallows of all species that I saw only a few years ago. Where once we had as many as 13 pairs of barn swallows nesting in our barn we now are luck to have two. It’s not only bees that are in decline… more needs to be done to protect wildlife. I want, we need, skies filled with birds and bees

    May 20, 2015 at 7:21 am

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