The birdy breeding cycle 2020 – 3: raising young

This year, most of the birds that visit my yard chose to build their nests in places where I didn’t see them. Only the brown-headed nuthatches, house wrens and Eastern bluebirds chose to use nest boxes. The Carolina wrens (Thryothorus ludovicianus) began to use a nest box but their nest was invaded by ants before I had noticed so they abandoned that site. Still, I was able to watch parents with babies, both at home and out on the nature trails.

There are two major kinds of baby birds. The altricial birds hatch as helpless young who must develop their sight and feathers, requiring parental care until they can fly from the nest. They include the songbirds that you may see often, such as chickadees, nuthatches, cardinals and bluebirds, whose babies are seen below shortly after hatching and after several days of development.

 

In contrast, the precocial bird babies can quickly move about on their own after hatching and are able to begin foraging for food themselves as they follow their parents around. In some cases, the parents may also feed them. Examples of precocial birds include killdeer, ducks and Canada geese (Branta canadensis) as seen below.

The nest I watched most closely this season was built by brown-headed nuthatches (Sitta pusilla) in a nest box. Carolina chickadees were also interested in that spot, but the nuthatches won out. Mama Nuthatch laid six eggs, four of which hatched. She and Papa were very hard workers, flying to and from the box countless times per hour. Like other seed-eating birds, they fed their nestlings insects because the babies need lots of protein for their development.

 

They were devoted parents, flying to and fro with food, carrying away fecal sacs and chasing off other birds who used the nest box as a perch. All their care was no match, however, for a pair of birds who are known to be quite aggressive during nesting season.

 

I first learned of house wrens’ (Troglodytes aedon) intolerance of other nesting birds in their vicinity when they invaded the nest of a banded female Carolina chickadee (Poecile carolinensis), whom I had named Chantal. Her babies were hatching and the wrens went into the nest during her absence and killed them. That experience made me hope they would not return to my yard the next spring, but they seem to like the area. This year they visited all the nest boxes in my yard and the male began nests in several of them to keep away other birds. It is thought they may drive away other nesters in order to reduce competition for food when it comes time to raise their own young.

 

The wrens finally settled on a nest box and I thought they would leave the nuthatches alone. Their young ones got to the brink of fledging and the parents were encouraging them to fly out. Sometimes, they would fly up to the box as a youngster peered out into the big wide world and just hover with the food in their mouth.

 

 

They would perch atop the box and call. Eventually two took the leap (which I didn’t see); I thought the others would follow the next day. The parents were busy in the morning and suddenly all activity ceased. I guessed that the other two had taken flight, so in the afternoon I took a peak in the box. To my utter dismay, I found the remaining two nestlings deceased; the wrens had pecked them to death. ☹ I buried them in my flower garden with a small Buddha statue marking the site.

 

 

The nuthatches continued taking care of their fledged babies. They would follow the parents to the feeder poles, crouch down and flutter their wings rapidly as they begged for a morsel.

 

Eventually, the parents found a nearby branch in a large willow oak where they would crack nuts and feed their offspring. As you can see, the spot got a lot of use and could be easily identified by the shredded bark. The whole family still goes up there to eat their nuts from the feeders!

Many adult birds appreciate bird feeders as “fast-food” stops for themselves while they spend most of their time searching for meals for their nestlings. Even the species who mainly eat seeds feed their babies insects because the young ones need lots of protein as they develop toward maturity. The Eastern bluebirds (Sialia sialis) in my yard and other areas seem to favor caterpillars as a food of choice for their developing youngsters.

 

 

 

The pileated woodpecker parents (Dryocopus pileatus) take turns sitting on eggs and bringing food for their young ones.

The larger raptors bring in heftier meals for their offspring. This red-shouldered hawk grew up alone; those of us watching the nest didn’t know whether only one egg hatched or something happened to a sibling. The parents would bring small mammals for the baby to eat.

 

A pair of great horned owl babies (Buteo lineatus), located by Mary, a locally well-known bird photographer, appeared to be growing well the couple times I went to see them. I never saw the parents bring them food but assume they were well fed as they were venturing out of the nest the last time I saw them (a process called “branching”).

 

It seems that a young bird’s open mouth is a trigger for parents that they can barely resist. Until they mature, the fledglings have a pale white or yellow area, or in the case of American crows (Corvus brachyrhynchos) reddish, where their beaks join. This becomes very visible when they open their mouths wide to beg for food and parent birds have a hard time resisting the urge to stuff food down their throats.

The Eastern phoebes (Sayornis phoebe) at a local park were following their parents around asking for food.

They exhibited both the crouched wing fluttering and wide-open mouths as cues that they wanted to be fed.

  

The downy woodpecker (Picoides pubescens) juveniles did not seem to beg as much as the other birds in my yard. They just perched close to feeders or their parents and eventually mom or dad gave them a bit of suet.

 

The European starling young (Sturnus vulgaris) are especially demanding to judge by their behavior at my feeders. These are larger birds and the offspring are as large as their parents,

They are capable of feeding themselves but spend a good deal of time with wide open beaks demanding to be fed.

 

 

 

The starling parents usually give in, but you can almost think they look exasperated.

At least the immature starlings can demonstrate well how a bird looks with a full crop (i.e., the enlarged part of the esophagus that forms a muscular pouch in which food can be stored).

In between all the feeding, the parents have one other important nest duty – keeping the nest as clean as possible. They do this by removing fecal sacs, as this prothonotary warbler (Protonotaria citrea) was doing last year.

 

Some adult birds will actually eat the fecal sac. This is because the nestlings do not completely digest their food and the sacs therefore still contain valuable nutrients that the parents can use. I can imagine the parents are glad to be done with this duty once their young have fledged, however.

When you’re out walking or watching bird feeders, it can be entertaining to observe the birds as they nest and raise their demanding children. And it’s good to know that you may even see adult birds begin to drive away their babies, either because they’re tired of feeding them or because they are busy with a second or even third brood for the season.

The birdy breeding cycle 2020 – 1: courtship and mating

Although we in the Northern hemisphere are already a little more than a month into summer, many species among our avian friends have not yet completed their breeding cycle. In my yard, many parents are still feeding begging (sometimes almost adult) children. Others are feeding young ones in the nest and some appear to be busy constructing new nests for a second or third brood. So, after a long hiatus in blogging, I decided to feature some of my bird friends, including the American goldfinch pair below (Spinus tristis) as they have worked on their new family lives in 2020.

American goldfinch P7130178 © Maria de Bruyn resSome of these photos go back to early spring. A series of misfortunes (including a crash of my laptop hard drive, a broken camera, loss of Internet) meant that I had a backlog of photos to process and then suddenly a large gap in photos taken. But I managed to recuperate some of the work and hope you enjoy the coming series of posts about the birds’ breeding and family life!

belted kingfisher

Breeding season is heralded by increasing bird song in the meadows, forests, fields and our yards. Males especially sing to attract mates and establish territories, but females treat us to songs and calls, too. This makes it easier to spot birds as the tree foliage gets thicker, especially if you have good hearing!

pine warbler P4175086© Maria de Bruyn                     white-eyed vireo P4123164 © Maria de Bruyn res

Pine warbler (Setophaga pinus)            White-eyed vireo (Vireo griseus)

Eastern meadowlark P4279816© Maria de Bruyn res            Orchard oriole P4279889© Maria de Bruyn res

Eastern meadowlark (Sturnella magna)     Orchard oriole (Icterus spurius)

Carolina wren P3316544 © Maria de Bruyn res                 blue grosbeak P4291500© Maria de Bruyn res

Carolina wren (Thryothorus ludovicianus)      Blue grosbeak (Passerina caerulea)

summer tanager P4291520© Maria de Bruyn res

Summer tanager (Piranga rubra)

Indigo bunting P6308502© Maria de Bruyn

Indigo bunting (Passerina cyanea)

Courtship is usually a sweet behavior to watch in my view. The male Northern cardinals (Cardinalis cardinalis) are especially devoted suitors, seeking out nice morsels to present to their intended mates, while among the American crows (Corvus brachyrhynchos), it’s the females who loudly call to their mates for some tasty bites.

Northern cardinal P4164873© Maria de Bruyn res

American crow P4080661 © Maria de Bruyn res

A fact that perhaps many bird lovers do not know is that few male birds have a penis. Like the female birds, most species’ males have a cloaca, a cavity externally located just under the bird’s tail and internally at the end of the digestive tract. Feces, urine, sperm and ova are all deposited in the cloaca. Birds who reproduce with this organ briefly rub their cloacae together (an activity called the “cloacal kiss”) whereby sperm from the male bird’s testes are transferred into the female’s cavity to unite with her eggs. During breeding season, the cloaca is slightly swollen and protrudes a bit from the bird’s body, facilitating the transfer. In the photo of this Carolina wren, you can see a slightly darker area under the tail indicating where the cloaca is found.

Carolina wren P7059955 © Maria de Bruyn res

red-headed woodpecker P4217162© Maria de Bruyn res

When ready for mating, the red-headed woodpeckers (Melanerpes erythrocephalus) seem to focus mainly on chasing away rivals and then snatching a quick mating session. The female woodpecker then takes a break from the chase to rest and have a bite to eat.

Some cliff swallow males (Petrochelidon pyrrhonota) seem to take advantage of females who are preoccupied with gathering mud for their nests for a quick tryst.

cliff swallows 2G0A3283© Maria de Bruyn res

The brown-headed cowbirds (Molothrus ater) seem to take their time for mating. This pair was occupied for at least 5-10 minutes in preparing for the upcoming production of eggs. At times, it seemed like the male was giving the female instructions on what to do once “the deed” was done!

brown-headed cowbird P5097676 © Maria de Bruyn res   brown-headed cowbird P5097677 © Maria de Bruyn res

Many birders do not like the cowbirds because they are parasitic nesters, i.e., they lay an egg in another bird’s nest so that the other bird will raise the young. Since the cowbird baby usually hatches before the other eggs, they either monopolize the food that the foster parents bring or they may even destroy the eggs laid by their foster mother.

brown-headed cowbird P5097682 © Maria de Bruyn res      brown-headed cowbird P5097686© Maria de Bruyn res

It’s been posited that the cowbirds evolved to use this strategy because they followed the bison in migration and therefore couldn’t stay in one place to raise their young. Others believe, however, that the birds developed the practice because dispersing their eggs over several nests gave their young a better chance of reaching adulthood.

brown-headed cowbird P5097689© Maria de Bruyn res

chipping sparrow P6256620© Maria de Bruyn sgd resThe quickest mating scenario I’ve witnessed came from a pair of sweet little chipping sparrows (Spizella passerina). I’d seen the two fluttering together at the feeders and had noted one sparrow chasing another away – which I now think was the victorious suitor driving away a rival. Then one July afternoon, the two flew to a dying cedar and sat close to one another on a branch. Suddenly, Mr. Victory mounted his mate but for what only seemed a few seconds – really very quick work indeed! She sat there with her rear end elevated for a bit and then the two went back to feeding – and soon after I saw them collecting nesting materials.

chipping sparrow P6256622© Maria de Bruyn res    chipping sparrow P6256623© Maria de Bruyn res

The birds in which the males do have a penis include some duck and swan species, ostriches, cassowaries, kiwi and geese. They differ from other birds in that development of the penis is NOT stopped in the male bird embryos during development (the case in cloacal birds).

The mallard males (Anas platyrhynchos), like some other ducks, unfortunately do not treat their partners well. They may mount the female very roughly. During a mating, she may be dunked underwater repeatedly and at length; occasionally, this results in her drowning. This behavior has been the subject of various studies and some newspaper articles with sensationalistic headlines (e.g., “The horrible thing you never knew about ducks)”.

Mallard duck P1232837 © Maria de Bruyn

Mallard duck P1232839 © Maria de Bruyn     Mallard duck P1232840© Maria de Bruyn

Once the actual mating is over, the birds devote most of their energy toward building a nest. While female ruby-throated hummingbirds (Archilochus colubris) must construct her nest and tend her babies alone, many other birds cooperate in the venture, like the Eastern bluebirds. Their efforts are featured in the next blog. (And if you’d like to see a previous post on courtship, it is here.)

ruby-throated hummingbird 2G0A4084© Maria de Bruyn res

Oh, those ravishing raptors!

Numerous people who attract birds with feeders feel regret and sadness when one of their avian visitors is captured to serve as a meal for a raptor in the neighborhood. I, too, feel that pity and discomfort when I see one of the hawks or owls capture a bird or animal because my thoughts go to the pain and fear that the prey must feel. But of course all wildlife has to eat and I want members of the predator species to survive as well. And the beautiful predators can be really interesting to observe.

 

A Cooper’s hawk (Accipiter cooperii, left) sometimes frequents my yard looking for a bird to take. This particular day in November last year, the hawk flew to the front-yard feeders but came up empty-taloned. Raptors, also known as birds of prey, are not the only birds that eat something other than seed. Some smaller birds, like the shrike, do so and many songbirds eat insects. The raptors, however, often go after prey that is fairly large in comparison to their own body size. In January this year, I came across another Cooper’s hawk at a nature reserve. The bird flew soundlessly past me to land in a tree downslope and paused for a bit before flying on, providing time for me to get a gorgeous portrait.

I’ve been lucky lately in seeing barred owls (Strix varia) at the Brumley Nature Preserve North. This owl was sitting silently next to a walking path, looking out over the adjacent field.

A couple weeks ago, I was startled by this barred owl who suddenly flew in front of me from behind my right shoulder. I hadn’t noticed him/her in a tree behind me. I tried to follow its flight but lost it. I thanked the owl for letting me glimpse it and said it would be nice if s/he came back so I could get another look. Sure enough, after I had turned back to the vicinity where I originally was surprised by the silent predator, it flew in and perched on a branch. The bird had a snooze, keeping one eye partially open to keep me in view.

  

Lately, I’ve been seeing many red-shouldered hawks (Buteo lineatus). They have been flying overhead at the nature reserves. The other day, two flew by calling raucously and then they alighted at the top of a far distant tree. I couldn’t get a photo but did see them mating in silhouette against the late afternoon sky.

  

 

A few weeks ago, a pair of red-shouldered hawks began constructing a nest just down the street from where I live. One afternoon, I happened to see them and one was collecting twigs to build or refurbish a nest.

 

 

   

This pair roams our neighborhood looking for prey; sometimes, one or both will perch in my back-yard tree for a little rest.

    

When one of the red-shouldered or Cooper’s hawks pauses for some time in the tree over the small pond, I figure it is watching for frogs or one of the chipmunks that live in the rocks surrounding the pond. The chipmunks appear to be very good at eluding capture.

 

 

A couple weeks ago, our neighborhood family of American crows (Corvus brachyrhynchos) was making a racket in my yard and when I looked out the window, I could see them harassing a hawk. I couldn’t make out why they were so angry but grabbed my camera for some shots through the window.

 

  

It turned out that the Cooper’s hawk had caught one of the numerous Eastern gray squirrels that live here. The squirrels sometimes annoy me but on the whole, I enjoy watching their antics, so I felt badly for this squirrel, who obviously was not going down without some struggle.

What made it easier for me to watch was that I didn’t really see the squirrel’s head and it was not making a sound. I think the hawk had silenced it early on when it had its claws around its neck and chest.

The hawk was determined and kept hold of the rodent, eventually subduing it.

The hawk as not unscathed, however, as you can see from the wound on its leg.

When the raptor flew off suddenly with the squirrel hanging from its talons, the three crows chased it in hot pursuit. I don’t know if they were just upset that the hawk was present or if they wanted to steal the squirrel away. On walks through the neighborhood, I am now regularly seeing the hawks in trees and on power lines. They are not too shy and seem to be adapted to the human presence in their territory.

  

While I may be feeling a bit wary for the other animals and birds when the stunning raptors appear, it still is a thrill to see one up close. Only about half of the red-shouldered chicks make it through their first year of life, so I hope the hawks keep coming by. And who knows, maybe we will have some of the long-lived birds who can reach an age of 15-19 years!

 

 

 

Not a white Xmas but some snowy portraits – part 1

Some of my friends really enjoy having a white Christmas holiday. When I was a child, I enjoyed it as well. Our town would usually have very snowy winters and I remember many times playing in snow piled a couple feet high. From my parents’ second-floor apartment, I liked looking out the window at the icicles, which could grow to 3 or more feet in length. It was disappointing when my mother broke them off, but she didn’t want one to fall and stab a passerby. Now, I think it is nice to see everything covered in freshly fallen snow; melting icicles and frosty dew can be pretty, but one day of this weather is enough for me. (As an adult, I now tend to think of low-income and homeless people who suffer from the cold and the dangers of icy roads.)

Still, seeing the wildlife in the yard and birds at my feeders during our very early Southern winter snowstorm in the first half of December was enjoyable. So in lieu of a white Xmas season, here is a two-part series of snowy portraits. (Remember that you can see a photo larger if you click on it; then just go back to the blog if you want to read more.) First up are the “larger” birds and a couple of the mammals who visited.

It did not take long for the Eastern gray squirrels (Sciurus carolinensis) to begin foraging in the snow; they were already busy on the first gray, darkish morning of our 2-day snowstorm.

 Lately, a family of 5 American crows (Corvus brachyrhynchos) has been visiting my yard often, the parents and three offspring who decided to stick around for a while. Although feeding bread to birds is not recommended, I admittedly do give the crows some whole-wheat pieces now and again as they seem to love them so much. So they come looking for that and occasional pieces of apple that I put out for them.

 

The brown thrashers (Toxostoma rufum) often feed on the ground but occasionally visit the feeders as well. They sometimes come as a pair but more often arrive as solitary visitors.

 

 

 

The European starlings (Sturnus vulgaris) are very beautiful birds with their winter plumage speckles. They do tend to be ill-tempered birds, however, creating havoc when they alight on feeders, chasing away other species as well as their own family members. Even the evening grosbeaks (Coccothraustes vespertinus), who visited my yard for the first time ever, gave way to the grouchy starlings.

 

The starlings look nice and peaceful when they sit still on a branch or rest on the snow-covered ground. When they fly up to the feeders, however, I sometimes chase them off. They used to only eat a bit of seed but now have also developed a taste for dried meal-worms and even suet. When a gang of 8-12 come, they can empty feeders in about 20 minutes. ANNOYING! (Both for me and the other birds!)

The blue jays (Cyanocitta cristata) often announce their arrival with loud squawking but tend to settle down fairly quickly. Their blue colors look beautiful against white snow.

  

The mourning doves are rather placid, slow and amiable birds, not minding if they have to share feeding space with other species, like the Eastern towhee (Pipilo erythrophthalmus). They do sometimes crowd out smaller birds when they alight on a feeder simply because their large bodies leave little extra space.

One dove was happy to sit a while in the snow; another took advantage of my bird bath de-icer to have a drink. I enjoy watching and hearing them, with their harmonious cooing – even their scientific name has a beautiful, melodic sound to it: Zenaida macroura!

 

The white-tailed deer (Odocoileus virginianus) came to see how much seed had fallen to the ground as their acorns and beech nuts were covered in white stuff.

 

 

The snow was so heavy that it cracked off the tops of some trees into my yard. It also crushed down the Japanese rose (Kerria japonica), which I will have to prune in warmer weather. The fallen branches of both trees and rose did provide the deer with some cold-weather snacks.

And my favorite snow portraits of the “big feeder birds” – the common grackle (Quiscalus quiscula)! The grackles at my feeders don’t really bother other birds, so I don’t dislike them as some other people do.

Those iridescent colors are just gorgeous and some of the bird’s expressions mirror my feelings in facing some recent challenges. But we both move on looking forward to brighter times! 😊

  

I hope the weather where you live causes you no problems the rest of 2018!

 

Avian generations in the making – part 3A: raising and feeding babies

So here in North America, it’s approaching winter and it may seem a bit weird to have another blog at this time on birds raising their young. But I wanted to complete the series even though it has been delayed because of my volunteer activities and commitments the past month. Also, it is now late spring in the Southern hemisphere so for some people this is seasonal and there are other birds around them that are getting ready for babies, though different species than these American robins (Turdus migratorius). Because this part kept growing longer as I worked on it, I’ve divided it into two parts – this one on raising the babies until fledging and the next one on fledging and post-fledgling care. I hope all of you who read this will enjoy it no matter where you live.

It’s fascinating to me to watch the birds during their reproductive cycle; I always learn something new. Once parent birds have completed a nest to their liking, the female lays her eggs and proceeds to brood them, with some species sitting on the eggs almost full time right away and others taking breaks.

           

Carolina wren (Thryothorus ludovicianus)              Eastern bluebird (Sialia sialis)

An acquaintance recently told me about a friend of hers who commented that she had seen a very pregnant goose that was so fat, she was waddling. The acquaintance proceeded to give an avian reproduction lesson to her friend – a woman in her 80s – who apparently did not know all birds lay eggs! Even after babies hatch, the Canada goose (Branta canadensis) may still look well-fed!

Some bird species have young who are “precocial”, that is, they are covered with downy feathers and have open eyes when they hatch and are soon able to feed themselves. These species include turkeys and ducks, like these mallards (Anas platyrhynchos), and the young often leave the nest soon after birth (which makes them “nidifugous” – good Scrabble word!). The newborns may look fuzzy but it’s not long before they start to take after their parents’ looks.

Other birds, such as songbirds, are altricial (as are human beings) – they are naked and helpless at birth and require considerable care before they can walk, fly and feed themselves. If you have some in a nest that is easily observable (and you can take photos when parents are not there so you don’t distress them), it’s interesting to see how the babies develop.

               

Carolina chickadees (Poecile carolinensis) on 18 and 22 April           

Brown-headed nuthatches (Sitta pusilla) on 13, 25 and 29 April

 

 

Eastern bluebirds (below)

     

As the mother incubates the eggs, her mate will often feed her so she doesn’t have to leave the nest. This young osprey (Pandion haliaetus) was assiduous in bringing his female life companion fish. Then as the babies hatch, in many species both the male and female parents get busy bringing the young frequent meals.  It’s estimated that Carolina chickadees, for example, will bring over 5000 insects to their brood before fledging!

Northern mockingbird (Mimus polyglottos)

     

House finch (Haemorhous mexicanus)  and Red-headed woodpecker                (Melanerpes erythrocephalus)

              

Orchard oriole (Icterus spurius)                  Blue grosbeak (Passerina caerulea

  

Eastern phoebe (Sayornis phoebe)

In some species, the previous year’s young will help their parents with the new brood. Brown-headed nuthatches and American crows are examples of this. A pair of Canada geese that I observed this past spring seemed to have a domestic goose helping them out.

The parents have other chores, too. They must keep the babies safe from predators – Both American crows (Corvus brachyrhynchos) and common grackles (Quiscalus quiscula) will be chased away by songbirds, for example, because these birds will raid nests to eat eggs and babies. But the grackles must also protect their own young against the crows, pursuing them non-stop to drive them away.

 

For other birds, protecting the young can be more difficult. This mother wood duck (Aix sponsa) was raising her brood in a pond that was home to at least three large snapping turtles (Chelydra serpentina). Ultimately, another birder and I thought she only had two ducklings survive.   

Keeping the nest reasonably clean is another chore. The babies make this task a little easier than you might think because they defecate into a mucous membrane that forms a sac. When you watch a nest box, especially when it gets closer to fledging time, you can periodically see the parents flying out of the box with a white blob in their mouth, which turns out to be a fecal sac. They either discard it elsewhere or sometimes eat it for some nutritional benefit.

        

Brown-headed nuthatches

This year, I was surprised to have caught a female blue grosbeak during the cleaning – it appeared that she was actually pulling the fecal sac from the baby! Later, I read that some species stimulate defecation by prodding the babies’ cloaca so they can get on with the chore. I also caught a photo in which a baby bluebird had just presented its rear end to the parent for removal of a sac. I could imagine that some human parents might think a fecal sac would be a cool avian adaptation for their babies to have – no more dirty diapers and expense for diapers either! (An idea for an SF short story?)

     

 

After all their efforts, the parents are usually ready for those babies to fledge – the subject of the upcoming last blog in the series.

 

 

* Not all the photos in this blog are of great quality, I know, but my intention was first to show behaviors and secondarily to have some nice shots in the blog.