Friday, March 25, 2022

Tree Swallow (Hirondelle bicolore)

       As March winds down, and April approaches, our thoughts turn to Tree Swallows (Tachycineta bicolor), soon to return to southern Ontario to dazzle us with their brilliance.


     These entertaining hirundines exhibit enough varied behaviour, with both predictability and the possibility of the unusual, to keep us occupied and entertained all day. 


     There are many aspects of Tree Swallow behaviour that defy immediate explanation, one of which is the preference for white feathers for the nest.
     In a fascinating book, (White Feathers, The Nesting Lives of Tree Swallows) by that most consummate of naturalists and authors, Bernd Heinrich, an interesting hypothesis is advanced.
     It is an established fact that some level of egg dumping occurs with Tree Swallows, meaning that a female not having a nest of her own, or for some other reason, will lay her egg in the nest of another pair. This action can only be successful if the resident female has already started to lay eggs, otherwise a strange egg suddenly appearing would be instantly apparent, and rejected. Furthermore, once the rightful occupant of the nest has laid even one egg, she would no longer be able to differentiate her own egg from the parasite egg since they are identical. It is postulated that a canopy of white feathers camouflages eggs in the nest, so the would-be dumper looking in would be unable to see the existing clutch.
     Francine Gilbert took several pictures of a swallow carrying a white feather, finally angling it to get it into the nest.



     In contrast with the male's fabulous gleaming plumage the female is quite drab, shown here peering from a nest box.


     This nest is amply lined with feathers, but not all are white, or even pale-coloured.


     One must conclude that white feathers are gathered preferentially, but other feathers are used when nothing else is available. Heinrich found that white feathers were so desirable, especially those in the 8 - 10 cm range, that the male swallow would take them right from his hand.
     The base of the nest is always made of dried grass as is shown below.


     The feathers are added at the end, with the point facing downwards and anchored into the substrate forming a canopy over the eggs.


     In addition to functioning as camouflage the covering of feathers probably also has a thermo-regulatory function.
     Here is a female at the lip of the nest hole, with a male flying by.


     It is an accepted fact that cavities are in short supply, with many species competing for them, so it has always been a puzzle to me that every year at SpruceHaven, perfectly good nest boxes remain unused, while others, identical in every way, become home to Tree Swallows, Eastern Bluebirds (Silia sialis), House Wrens (Troglodytes aedon) and Black-capped Chickadees (Poecile atricapillus).
     Heinrich makes the interesting observation, "I now had the hunch that the swallows were protecting sky space rather than one nest box or another." Why this would deter other species, however, remains unclear.
     Males are not usually tolerant of each other during the breeding season, but here is an interesting example of two males seemingly interested in the same nest box, without antagonism - at least none that we observed.


     A mated pair is more to be expected.


     Here are a few more pictures of this delightful bird, the first of a male and the second and third of females.




     The goal of all species is to pass on their genes and here is the result of a successful Tree Swallow season, as recent fledglings gather to practice their flight and food-gathering skills.


     They have a long and arduous journey ahead of them, with many dangers along the way, to winter in Central America, primarily in Honduras, with some birds even going as far as northern South America. 
     Many will not make it, but those who do will set out to return to their place of birth the following spring.
     As always, we will be here to welcome them and provide a snug nest box they can call home. It's the least we can do.  



David M. Gascoigne,
David M. Gascoigne,

I'm a life long birder. My interests are birds, nature, reading, books, outdoors, travel, food and wine.

77 comments:

  1. Hari Om
    Stunning... and interesting insights! YAM xx

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  2. I have never heard of the Tree swallow. What a nice post with beautiful pics.
    Why do you use two scientific names: Hirondelle bicolore - Tachycineta bicolor?
    Lisbeth

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    1. We are a bilingual country, Lisbeth. Hirondelle bicolore is the French name for this species.

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    2. I thought that might be the reason, but on the other hand I thought that the scientific name was the same all over the world. Then I learned something new.

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  3. Thank you, David, for a wonderful post honoring the Tree Swallow. It is a fascinating species. They are beautiful to behold and the male plumage in bright light is simply dazzling.

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  4. ...fabulous shots of these iridescent beauties.

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  5. The Tree Swallows are very beautiful, and the color are so pretty. We neigbour have a big barn, and there lives Hirundo rustica every summer. I like to watch them when they fly.
    Hugs and kisses, Marit

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  6. Beautiful photos David, I never have heard of this swallow. I like swallows.

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  7. What a wonderful post. How I wish that the tree swallows could come past our yard - there are white feathers in plenty for them here...

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    1. That is so true, Sue. I have some and I am not sharing with the swallows!

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  8. They are beautiful, esp. the male one with deep blue colour.

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  9. Thanks for sharing your insight of these beautiful litte birds.

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  10. Elles sont jolies ses hirondelles, on pourrait les observer des heures, les plumes blanches ne sont pas nombreuses ici, je trouve souvent des noires ou celles de rapaces. Bon weekend

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  11. The Tree Swallows and their cousins are passing through and some of the cousins, like the Purple Martin, will be staying with us through the summer. If the swallows have returned, spring must truly have arrived.

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  12. Querido David siempre es una inmensa alegría ver las primeras Golondrinas. No conocía esta Golondrina y es realmente hermosa y su manera de hacer el nido es muy curioso e interesante. Muchas gracias. Feliz fin de semana. Abrazos y besos para ti y para Miriam.

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  13. I know some areas to look for the swallows here. Such beauties. Great post and wonderful photos!

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  14. These are wonderfully photographed.

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  15. Learned a new word today, thanks. I'm enjoying your more in-depth posts on bird groups like this.

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  16. These are fabulous photos of tree swallows. I also learned a lot in this post. I bet a nest layered with feathers is a wonderful place for young featherless babies. The tree swallows will be back sooner than later, and I won't look at them the same way again. I will look at them in a much better way. Happy weekend. hugs-Erika

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  17. I only have seen brown swallows. They make a summer evening a delight, soaring and swooping and eating mosquitos.

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  18. I had never heard of Tree Swallows before but they're obviously fascinating little birds. Your photos are lovely as always.

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  19. Thank you for such beautiful photos, and for the information about this swallow. Such beauty wrapped in blue, is always searching for the white feathers.

    I like your new set-up here. Easier to navigate.

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  20. I've watched tree swallows with great admiration but I did not know about their nesting habits. Very interesting.

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  21. Great to see the photos which are nice and clear. The nest looks intriguing.

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  22. Fascinating! I don't know what kind of swallows we had at the last apartment building I lived in (Fargo. ND) but they were gorgeous multicolored blue but with longer tails. We just called them barn swallows. They made nests on top of the balcony lights--LOL! You couldn't go onto your balcony without being dive bombed and scolded inside. Lovely graceful birds. :)

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    1. Based. In your description, Rita, I am quite sure they were in fact Barn Swallows, so you had it right.

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  23. Fabulous birds, and their nests are always little works of wonder. Have a great weekend, take are, hugs, Valerie

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  24. Oh, they are beautiful! And interesting to see them "at work"! Must make a very welcoming home to "the kids". Sweet.

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  25. Hi David.

    Swallows are also very beautiful birds.
    Nice to see the nests too.
    Beautiful pictures.

    Greetings from Patricia.

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  26. Hi David,
    I know there are many kinds of swallows, but this one is new for me. It doesn't show up in the Netherlands, but maybe I have seen it once abroad. We have got here usually four different kinds of swallows. Spring has begun, so I hope to see them soon again.
    Greetings, Kees

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    1. If ever you visit Ontario in the spring, Kees, I can show you this species, and several others unique to the Americas too.

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  27. Hello David,
    Beautiful post and photos of the Tree Swallows. I am looking forward to seeing them return here for the summer. Thank you for linking up and sharing your post. Take care, enjoy your weekend. PS, thank you for leaving me a comment.

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  28. We love to watch the swooping flight of all swallows. Your notes about the birds’ behavior are really fascinating, especially the white-feather mystery.
    best… mae at maefood.blogspot.com

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  29. Buenos días, estimado David, preciosa entrada, esa golondrina azul de árbol no la conocía y he quedado prendado de su belleza. Que gusto saber que funcionan esos nidos y que bien trabajados están. Gran labor la realizada.
    Gracias siempre por mostrarnos tanta belleza estimado profesor.
    Un gran abrazo amigo y compadre naturalista y gracias de nuevo por mostrarnos tanto interés, cuidados y respeto con todas las bellas criaturas que pueblan nuestro planeta.

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  30. There are so many varieties of swallows. Ours nest under the dock or bridges and build mud nests.

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  31. Hi David - wonderful photos from both of you ... thank you - in fact fun ones! Amazing how thoughtful facts, studied over years, are uncovered ... and there's always wonderment ... gorgeous - our feathered friends here are enjoying the weather now, next week - we'll be back shivering ... how those little tiny pots of life survive the extremes is beyond me. Cheers and enjoy more of Spring - Hilary

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  32. Beautiful photos and interesting information!
    Have a wonderful weekend!

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  33. You take such amazing photos! We see a lot of Swallows here but it sure is hard to get a good photo when they are swooping overhead. Love seeing these nesting!

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  34. What beautiful birds! That is really fascinating about the feathers in the nest -- brings new meaning to the term "feathering the nest" that I never thought about. Wonderful photos and isn't it nice to see them back!

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  35. Hello David,:=) Miriam's photos are truly exceptional. The male is a beauty, as his feathers take on a blueish colour in bright lighting, but the grey female is also lovely. The information about their nests is curious.The way they place the white feather stalk downwards so that they curl over, and camouflage the eggs and chicks is interesting. I wonder if this behaviour is used by other nesting species! Barn Swallows which are the only ones I see, sometimes nest in our outhouses, but they are very protective of their nests and dive bomb anyone getting too near. Thank you for another brilliant post David.
    Hugs from Portugal.

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  36. Thank you, David, for yet another informative, and beautifully illustrated, post. The plumage of the males is wonderful!

    The discussion on the collection of white feathers I found particularly interesting, but it also caused me to reflect on feather collecting here. We often see House Sparrows collecting feathers, and they are nearly always white ones! I shall pay particular attention now to see if this trait appears with other birds.

    Best wishes to you and Miriam - - - Richard

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    1. I am starting to collect white feathers in anticipation of the breeding season!

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  37. Las golondrinas son las anunciadoras de que la primavera ha llegado, su presencia da alegría a nuestros tejados, por aquí son muy bien recibidas.
    Las fotografías son preciosas!
    También me gusta mucho el cambio de plantilla que le has dado a tu blog.
    Muchos besos!

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  38. Extraordinary images David. They ARE beautiful. I find the nest boxes you captured in photo of great interest.

    Thanks for taking time to share these with us!!

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  39. Esta golondrina no se encuentran por aquí. Pero sí la común, un ave que siempre me ha gustado, desde que era una niña. Me encantaba oirlas cantar al amanecer, antes había muchísimas, ahora quedan pocas. Las fotografías están preciosas. Abrazos fuertes para Miriam y para ti.

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    1. Demasiados pájaros están en declive, Teresa. Besos.

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  40. Un gusto leerte amigo por la buena información que nos dejas siempre.El plumaje de esta especie es una maravilla. Por aquí se ve la golondrina común. Pronto empezaremos a verlas.
    Os deseo un buen domingo a Miriam y a David.
    Un abrazos.

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  41. Wonderful post. I have now signed up to follow along.

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  42. So many interesting things about swallows. I love to watch them fly and snatch insects out of the air. Great photos!

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  43. Nest building is such a delicate and scientific process. I love to see the swallows dive and scoop water on the go, all in one motion.

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  44. I found it fascinating,to learn about the way they build their nests and lay eggs. Pictures were spectacular!

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  45. I've never seen one, though the map at Wikipedia gives me hope :)

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  46. first of all my compliments for your beautiful headere with kingfishers :-)))))))) Just beautiful!
    There is quite a change on your blog I see and it looks really beautiful. You even have a "read more". I wouldn't know how to do that.

    Beautiful pictures of the swallows and also in the Netherlands they will soon return from the winter. Your photo series is fantastic with a beautiful litter too :-)
    A big hug from the Netherlands xo

    Helma

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  47. Very interesting about the egg dropping. I need to look up and see if we get those birds here in my area. I'm not familiar with them. As always such wonderful photo's. Odd too isn't it that the male is less colorful...typically aren't the males in many species the more colorful?
    Sandy's Space

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    1. Hi Sandy: I have just read through the text and I am not quite sure how you have concluded that the female is more brightly coloured. That is certainly not the case.

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  48. The male is more beautiful than the female. Love the gleaming feathers. Thanks for showing how they build their nest.

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  49. Reading about how these swallows build their nests is interesting. I know dogs are colour blind but definitely not swallows since they so prefer white. Amazing also how they arrange the feathers in a particular orientation. They have better house keeping skills than me! Egg dumping sounds like a free ride to get one's kids raised by another parent bird. I think we have only 2 types of swallows here - barn and pacific swallow

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  50. I really enjoyed your informative post about these swallows. Your photos are amazing too.

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  51. I still have a lot of pain and tears sometimes when I think about the birds that don't make it to the end of the migration. So much effort on the part of the parents that life is sometimes cruel.
    I hope there will be many pairs this year David, your photos are wonderful and I am waiting for this year's. Congratulations to both of you and thank you :-)
    Big kisses

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    1. Life is often cruel, Nathalie. I am quite sure that most Ukrainians would agree with you.....and Yemenis......and Syrians......and women and girls in Afghanistan.....and wolves in the American West.....and all the creatures of the Amazon rainforest......and so it goes. At heart, we humans are quite despicable.

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  52. The presented swallows on your blog are fascinating birds. I've never heard of this swallow. I am delighted with your perfect photos.
    David, thank you so much for your kind words in these difficult times.
    Kisses and greetings:)
    Łucja

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  53. I have a great love of swallows. In New Zealand when I played croquet they were for ever flying by and taking insets that I couldn't see from within a few feet of me - often of my face. We occasionally get them o the Island here but I rarely see them.

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    1. They doubtless were Welcome Swallows there, Graham. A fitting name, don't you think?

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    2. They were, indeed, Welcome Swallows. I always thought that it was a wonderful name to give a bird and a very appropriate one.

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  54. Hello David, at first the new look of your blog is wonderful. Than this story of this birds is amazing and not known to me that these birds nest in nestboxes. Than the behaviour of the egg dropping is very special as well. If it helps the species why not. Great photos as well.
    All the best from Belgium,
    Regards,
    Roos

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  55. Dla mnie to bardzo ciekawe ponieważ nie widziałam jaskółki, która gniazduje w budce. Nasze jaskółki lepią gniazda z błota lub robią je w norkach na brzegach rzek.

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    1. You will have to visit us, Ludmila, and we will show them to you!

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  56. Buenísima tu publicación sobre las golondrinas, se ve que la primavera ya está progreso y arribaron las aves más icónicas de esta estación del año. Las fotos me gustan, muy buena calidad; esta golondrina es bastante parecida a unas de por aquí, en mi pueblo llegan dos de este género, una en primavera y la otra a fines de otoño; luego vi otra pero más al norte del país... es que tenemos 11 especies para ver, y solo en mi pueblo con suerte se ven 7 u 8 o quizás 9, pero normalmente 5 siempre se ven. Un gran abrazo

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  57. I have seen this one on my trips. It is a beautiful swallow :)

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  58. My goodness, how do you have time to read and respond to all of your comments ... and this is just one bird of many. I love the Tree Swallow. They are beautiful and we have them in our forest preserves where the little houses are provided for them. When we lived on the lake we had Barn Swallows that built their nests in the corners of the boat canopes on the piers. They were a wonderful addition as they spent their evenings eating the mosquitos which, I am sure, reduced the number of irritating bites we had to deal with. Anyway, that is the first I knew of the lining the nest with white feathers ... nature never ceases to amaze ...

    Andrea @ From the Sol

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