Category Archives: migration

The maker of spoons – a bird delighting people worldwide

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1 roseate spoonbill P8040500 © Maria de Bruyn card (2)

In different countries, the bird genus Platalea has given rise to similar common names for birds in this group, all based on their unique bills. In Dutch, lepelaar used to mean “maker of spoons” but now the first dictionary definition refers to this type of bird. Spanish speakers gave these avians the moniker “spatula bird” (pájaro espátula), while in many other languages they are called the “spoon birds” (Romanian, Icelandic, Bahasa Indonesia, Shona, etc.). In English, we call this unique animal the spoonbill.

6 roseate spoonbill P8040996© Maria de Bruyn res

Many people find spoonbills fascinating, including me, so it was with happy anticipation that I traveled to see an immature roseate spoonbill (Platalea ajaja) that had decided to forage in our county. When I arrived, I scanned the cow pond where the bird had been seen, but the only animals there were several large cows! I decided not to wait around since the cattle were enjoying the water and it was unlikely any birds were going to join them.

A couple days later, I returned, parked along the road and walked up to the fence to peer down at the pond again. A great egret (Ardea alba, below) was foraging, some barn swallows (Hirundo rustica) were occasionally swooping over the water, and some Canada geese (Branta canadensis) were wandering around but no spoonbill was in sight.

2 great egret P8040974© Maria de Bruyn-sgd res

3 roseate spoonbill P8040309 © Maria de Bruyn resIn contrast to other birds, spoonbills do not vocalize much except for some low grunts made while they are feeding. I didn’t hear any bird sound and after some 20 minutes or so, I thought perhaps the young spoonbill had decided to move on. Then suddenly s/he emerged from grasses bordering the pond and I was able to observe the bird for quite some time.

4 roseate spoonbill P8040325© Maria de Bruyn res

5 roseate spoonbill P8040961© Maria de Bruyn resThere are six spoonbill species worldwide; the roseate spoonbill lives in North, Central and South America. The other five species have white plumage, while the roseate spoonbill adults have a white neck, bare head, bright pink back and rump feathers and a greyish bill. The immature birds have feathered heads their first three years and pale pink feathers. The color on our county’s visitor showed up more brightly when the sky was overcast rather than sunny.

The spoonbills’ coloration comes from their food. Their diet consists of crustaceans, snails, fish and aquatic insects found in both fresh and salt water. Aquatic invertebrates have pigments called carotenoids and when the spoonbills eat them, their feathers turn pink.

7 roseate spoonbill P8041138 © Maria de Bruyn res

Depending on the birds’ age, location and breeding status, the color intensity can vary from a pale pink to very bright magenta or carmine.

8 roseate spoonbill P8040580 © Maria de Bruyn card (2) 9 roseate spoonbill P8040517© Maria de Bruyn res

10 roseate spoonbill P8040340 © Maria de Bruyn resWhen chicks are born, they do not yet have a spoon-shaped bill; it only begins to flatten out when they are 9 days old; the final shape is achieved by 39 days. The bill can be 5.7 to 7.1 inches long (14.5-18 cm). It is about an inch wide just beneath the birds’ eyes and then widens to about 2 inches at the end.

It might seem that these very large bills could make life difficult for the spoonbills but they use these spatula-like appendages efficiently when feeding. Their nostrils are located at the base of the bill so that they can breathe while foraging.

11 roseate spoonbill P8040346 © Maria de Bruyn res

Their technique is to stalk slowly, leaning forward with their bills submerged as they swing their heads from side to side. Israeli scientists discovered that when the bill sways back and forth, it creates tiny whirlpools that suck up prey submerged in the water. When the prey touches the bird’s bill, it snaps shut as nerves at the bill tip are stimulated; the prey is then usually swallowed whole.

12 roseate spoonbill P8040425 © Maria de Bruyn res

13 roseate spoonbill P8040365 © Maria de Bruyn res

Spoonbills prefer to feed in shallow water that is usually less than 5 inches deep. This would account for the fact that the spoonbill I watched was making circuits around the edge of the pond, never going into the center.

14 roseate spoonbill P8040395© Maria de Bruyn res

15 roseate spoonbill P8040566© Maria de Bruyn res

16 roseate spoonbill P8040703 © Maria de Bruyn res

One thing in particular struck me as the cow pond bird walked and stalked. When s/he raised his/her head and opened the bill, it looked to me as if the spoonbill was laughing or at least looking very friendly and smiling!

17 roseate spoonbill P8040521© Maria de Bruyn res

18 roseate spoonbill P8040427© Maria de Bruyn res (2)

19 roseate spoonbill P8040524© Maria de Bruyn

20 roseate spoonbill P8040825 © Maria de Bruyn resIn the USA, spoonbills have traditionally bred in Florida, Louisiana and Texas. After breeding, they disperse. It is especially year-old birds who are increasingly being seen along the Eastern coast. To find them further inland had been more unusual but in recent years they seem to be moving away from the coast as well. This year several spoonbills have been spotted in the Piedmont region in addition to our Orange County visitor.

21 roseate spoonbill P8040483 © Maria de Bruyn res

23 roseate spoonbill P8040502 © Maria de BruynBy the late 1800s, the roseate spoonbill was endangered in North America because the birds were either killed for their feathers (to make decorative screens, fans and hats) or they abandoned their nests because they were near great egrets who were being killed for the millinery trade. When that trade ended, their numbers rebounded but rising sea levels, degradation of water quality and loss of wetlands has now decreased their breeding sites. The spoonbills are still listed as a species of concern in Florida and Louisiana.

22 roseate spoonbill P8040377© Maria de Bruyn res

As climate change progresses, increasing numbers of roseate spoonbills are starting to move north. Protection of wetlands in our and other Eastern states would therefore benefit this species, as well as other animals that depend on this type of habitat. And more of us outside the southernmost states may get the chance to observe these unique birds in the future!

Red-winged, rusty and ravishing – black bird delights!

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Two species of birds that I enjoy seeing during the autumn and winter months in North Carolina (NC) are red-winged blackbirds (Agelaius phoeniceus, above left) and rusty blackbirds (Euphagus carolinus, above right). Both species breed in the northern USA and Canada, traveling to the southern USA during the colder months.

There is also a population of red-winged blackbirds that nest in NC’s Piedmont region. I’ve seen them collecting nesting material at local ponds and wetlands but have never had the pleasure of seeing their nests or watching them feed their young.

The red-winged blackbirds have two avian records to their name: 1) currently perhaps the most numerous land bird in North America, with counts of more than 1 million birds in a flock!! and 2) one of the most researched wild bird species anywhere.

The male red-wings call the attention of females with the red and yellow patches on their wings. It turns out that those with larger patches are more successful in disputes with other males for territory and mates.

     

Some males have been recorded as having up to 15 mates in their territories during a season, but it turned out that 24-50% of the nestlings had another male as a parent!

 

The females look very different from the males with beautiful reddish-brown striping. Their faces are marked by off-white eyebrows.

 

 

They often nest near other red-wings.

             

Doing so means that their nesting area has multiple parents on the alert for predators.

It is interesting that Native American languages also had common names that describe their physical characteristics (red patch, spotted, marked). The longest one that I read about was “memiskondinimaanganeshiinh” (Ojibwa meaning “a bird with a very red damn-little shoulder blade”)!

 

 

During breeding season, the male rusty blackbirds have glossy black plumage with a greenish sheen. At other times, they have rusty tips to their feathers, giving them a mottled look.

The females may also look a bit mottled but have much more light brown and beige coloration.

 

In contrast to the numerous red-winged blackbirds, the rusty blackbirds used to have high numbers but have lost up to 85-99% of their populations during the past 40 years for unknown reasons.

 

The sharp decline is so mystifying that scientists have formed an International Rusty Blackbird Working Group to investigate what is happening.

   

 

One possible explanation is a decline in wetlands, especially in the Southeastern USA where 80% of the birds overwinter. A resurgence in beaver ponds may be helping them, which shows how protecting one wildlife species can also assist another one. I have indeed seen them in areas where beavers have been active.

 

The rusty blackbirds that I spotted were indeed using local wetlands in their search for food, turning over the sodden leaves with their feet and beaks as they searched for sustenance.

The International Working Group is asking people to report their sightings of these birds to eBird to help track the species.

To close this blog, I wanted to share just a few photos of some other birds who are a beautiful black color: my faithful American crow couple (Corvus brachyrhynchos).

They have been visiting with one of their offspring from last year, just as they have done in previous years.

 

 

Unfortunately, it appears that one of the birds has somehow suffered an injury to one leg and foot. S/he has been hopping around on the ground and can fly well, but it is a mystery as to what happened to hurt this large bird. Perhaps a tussle with one of the neighborhood hawks?

 

 

 

 

Spring weather is beginning in our area, which means some avian species will be leaving us and some new ones will be arriving or passing through in the coming weeks. The next blog will feature a few of our feathered friends who will be leaving.

A third look at our 2020-21 “superflight” irruption – red crossbills

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As mentioned in my last couple blogs, finches that usually reside in Canada and the northern USA have come south this year because of a dearth of food in their usual habitats. One of the factors contributing to the shortage is the varying cycles in which cones, seeds and fruit ripen among different tree species.

Not every tree produces an equal amount of seeds or berries every year; for example, this year my red cedars didn’t have very many juniper berries and by the time the cedar waxwings arrived, the American robins (Turdus migratorius) had already cleaned out the crop. Periodically, many of the different tree species up North have low seed production at the same time, so that birds who eat different kinds of crops all need to go elsewhere for sustenance in the winter.

An interesting speculation from scientists in the Finch Research Network is that this synchronized low seed production evolved as a means of limiting food supplies for seed-eating (red) squirrels who could reproduce greatly and then wipe out all the seeds so that no new trees would grow. Jamie Cornelius, a researcher at Oregon State University, explained that “birds are mobile, and can find cone crops somewhere else,” while the sedentary squirrels then need to curtail their reproduction. In addition, some birds have evolved biological processes that make it easier for them to cope with food scarcity.

Red crossbills (Loxia curvirostra, called common crossbills in Europe) molt quite slowly, losing only a few feathers at one time, which makes it possible for them to fly elsewhere at any time in search of sustenance. They are normally not migratory but will travel for food, so in December 2020, local birders were quite excited when red crossbills were spotted at a state game lands in a neighboring county.

I was not enthusiastic about going to a hunting zone but had heard that the duck hunters were usually only busy early in the morning. So I donned my bright orange vest and ventured out on the two-mile walk to the spot where the crossbills had been seen. I waited around for a couple hours but they didn’t show, although I was looking for the reddish males and yellow females to make an appearance.

I didn’t give up. On my fourth visit to the game lands, I finally saw the crossbills (although I didn’t realize it immediately as they were so far away and my cataracts make seeing anything distinctly at a distance quite difficult. It was only after I enlarged one photo on the camera that I saw what they were! Remember, you can see a photo larger if you click on it and then back arrow to the blog).

I first thought perhaps some grosbeaks had flown in, so I focused as well as I could on the distant trees and took photos. I was thrilled to see that I had finally photographed those elusive birds – giving me a “lifer” for 2021. 😊

Sometimes it’s not easy to understand why a certain bird species has a particular common name. For example, many people would call a red-bellied woodpecker a red-headed woodpecker because the red on the head is much more noticeable than the hue on its belly. But the crossbills exemplify their common name quite accurately with their upper bills that curve down over their lower bills. A good view of their beak can be seen at the All About Birds website.

At first sight, one might think that this beak arrangement would make it difficult for them to eat, but this morphological adaptation means that they can extract seeds from conifer cones that are still closed, which other finches cannot do. Their bill structure makes it possible for them to hold onto a cone, pry it open with their beak and then take out the tightly-packed conifer seeds with their tongue.

This specialized anatomical feature does restrict the crossbills’ diet somewhat. They do eat some other seeds, berries and insects from time to time and they also ingest grit and sand from time to time as having these substances in their crop helps them to digest the conifer seeds.

What also makes these finches very unusual is that there are at least six – and perhaps as many as 11 – sub-species in North America who differ in the size and shape of their beaks and the type of calls they make. Their unique vocalizations has led to each sub-group being designated as a “call type” and each type feeds on a different conifer species. They move about in groups and call to each other while flying from tree to tree. Some scientists think they may be communicating about the feeding possibilities in each cone-laden tree they pass!

Another behavior that is distinctive for the red crossbills is that they breed at any time of the year, whenever sufficient food supplies are available. When a female and male form a breeding pair, they imitate one another’s flight calls so as to keep track of one another.

 

Unfortunately, unlike other irruption species such as evening grosbeaks and pine siskins, the red crossbills are rare visitors to bird feeders.

When I heard that crossbills had been seen at a game lands area much closer to my home, I made a couple more treks in hopes of spotting them. The first day I was incredibly lucky as I was the only person visiting the reserve and could walk at a leisurely pace in quiet fields except for the chittering of multiple bird species, including a hermit thrush.

Unfortunately, I didn’t manage to see any crossbills flying overhead. Another visit to this nearby game land was shortened considerably when I discovered it was quite noisy with two hunters accompanied by a pack of baying hounds who were yowling very loudly and frequently. I high-tailed it out of the reserve and resolved to be happy with my one and only crossbill sighting (so far). Hopefully, one day I’ll be able to see them more closely – something to which I can look forward with great anticipation!

A “superflight” irruption for North Carolina – the pine siskins

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As mentioned in my previous blog, North Carolina’s Piedmont region is experiencing a spectacular winter irruption of multiple finch species. So many birds have migrated south from the northern USA and Canada that scientists are calling this a “superflight” year. The first to arrive in my yard during this irruption were the pine siskins (Spinus pinus).

Scientists don’t yet know as much about siskin migration as they would like to know. From 1960 to 2011, almost 675,000 siskins were banded but only 2000 of them were ever spotted again.

However, it is known that the siskins enjoy eating many types of seeds. The finches’ usual diets up North center around the fruit and seeds of spruce, pine, hemlocks, maples, and beech trees, among others. Some species favor certain trees, while others enjoy eating a large variety of seeds.

In “mast years,” the forests provide large amounts of seeds that both feed animals (e.g., birds, squirrels) and provide the germination material for new vegetation. In other years, the forests produce very few crops because of fires, drought, and outbreaks of spruce budworms that eat the needles of spruce and balsam firs, which can kill the trees. In 2020, it was noteworthy that authorities in Quebec were unable to completely treat the forest trees for budworms because of the COVID epidemic.

 

Some trees also have slow biological cycles. For example, the Eastern white pine (Pinus strobus), known to the Iroquois as the “tree of peace,” has cone production that peaks every 3 to 5 years.

When mast years have taken place and there are large budworm infestations, the finches have plenty to eat and their numbers increase substantially. When the following seed- and cone-poor years occur, the large populations then need to travel further away to find sufficient food supplies and that is what has now brought them to our area.

The pine siskins arrived in my yard in late autumn. They came in a large crowd, with some 30 birds flocking to the feeders at a time. Most of these little brown and beige birds have a trace of yellow on their wings.

About 1% of the siskins – all males – have more yellow or yellow-green coloring on their backs, heads and under-tail coverts. These so-called “green morphs” also have less streaking on their chests. The siskins above may be in this group. Interestingly, whereas female birds of many species prefer brightly colored males as their mates, female siskins appear to choose males with less yellow to distinguish them.

 

What really distinguishes the siskins for me – in addition to their penchant for visiting in large groups – is their feistiness. They seem to be very troubled by the idea that there may not be enough seeds to satisfy their appetites if many other birds are around.

Below you see them challenging a house finch, a downy woodpecker and cardinals.

 

And this includes not only birds of other species but also their species mates with whom they arrive! They first will open their seed-filled mouths to “yell” at the incoming diners.

Next, they may open their wings in a challenging display.

 

Sometimes they seem to be taking food from another’s mouths! (But perhaps this is not aggressive but a sign of care between family members?)

Finally, they will fly at their food rivals in an effort to drive them off.

Unlike other members of the finch family, the siskins not only eat a very large variety of seeds from conifers, deciduous trees, grasses, weeds and flowers. They also forage for insects and have been seen to drink from sapsucker sapwells in trees.

A group of siskins can clean out a feeder with mixed seeds in my yard in very short order indeed. They have developed body mechanisms to help them survive cold nights: increasing their metabolic rates and gaining body fat for the winter.

 

This is accomplished by eating more seeds than they can process right away; they can store seeds weighing up to 10% of their body mass in their crop (part of the esophagus) for a short period so that they have access to more energy during the night!

 

Some local birders who were delighted to see them at the beginning of the season are now occasionally voicing “regrets” since large groups continue to visit their feeders. They could refrain from putting out seed and hope the flocks move away so they don’t spend so much on bird seed, but many birders would then miss seeing the other species and don’t want to forego that pleasure.

 

 

Fortunately, the siskins have been eating seeds from crepe myrtles and other trees in my yard so their visits to my feeders have been somewhat sporadic when the weather is mild. When it rains or gets very cold, they return in feisty groups!

“My” yard siskins have also refrained from pecking at the cement of my brick house. Other birders have seen them chipping away at chimney and brick cement – they do this get at minerals contained in the cement.

 

While the siskins migrate in very large groups (e.g., flocks numbering up to a few thousand individuals!), they are still considered to be a common bird that is showing a steep decline in numbers. They are vulnerable to predators as well as contagious diseases spread at feeders such as salmonella.

Although we are still in the throes of winter in North Carolina, spring is fast approaching and it’s uncertain how long these irruption birds will stay. I’ll miss these lively little visitors when travel back up North!

A gathering of gorgeous grosbeaks

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If you know birders, you’ve undoubtedly heard that this 2020-21 winter season marks an “irruption” year – a period when large numbers of certain bird species migrate to places where they’re usually not seen. This year is especially notable because it is one of the largest mass migrations that has taken place in about 25 years.

The scientists who study irruptions are calling this season a “superflight,” because all the species in the finch family that breed in the boreal forests of the northern USA and Canada have been moving south. Here in the Piedmont, we’ve been lucky to see several of these species.

The finches that have drawn the most attention from local birders are the evening grosbeaks (Coccothraustes vespertinus) with their eye-catching colors and plumage. They tend to move about in flocks and when they land at feeders, they appear more than willing to share with other birds, like a red-bellied woodpecker (above) or pine siskins (below).

When they land on a feeder, however, they may crowd out others due to their size.

While the evening grosbeaks don’t seem quarrelsome like some other birds, they may still have territorial defense encounters when they are vying for food. Perhaps that is what happened to this female with what appears to be a slight injury below her eye. It is unlikely that it would have come from escaping another type of assault as it has been reported that they have no known predators!

The females are subtly colored in shades of gray-beige with touches of green and yellow on their flanks, neck and near their throat. Their wings are marked with black and white patches.

 

Their coloring may look a bit different depending on the quality of the light and how overcast the day is.

The males are eye-catching due to their vibrant yellow and black plumage, featuring a notable dark yellow stripe over the eyes and a bright white patch on black wings.

Both females and males have the very thick, conical bills characteristic of their species.

Watching them at breeding time would be interesting as it does not involve song but instead features the males dancing for their prospective mates.

In the summer, the evening grosbeaks eat insects, including the spruce budworm, which is a tiny caterpillar. Their winter diet includes large seeds, berries and tree buds; maple samaras (papery winged seeds) and sunflower seeds are favorites (especially the gray-striped kind).

In 2018, a few individual evening grosbeaks were spotted in the Triangle but not many people had the chance to see them. I was fortunate to have three visit my feeders for an afternoon when it was snowy.

This year, none have visited me, but they have been very present in our area, especially at the feeders of bird enthusiasts Bert Fisher and Leto Copeley. This lovely couple welcomed birders to visit their yard by appointment (with limited numbers of visitors wearing masks in the large area).

 

Bert kindly updated everyone on the birds’ comings and goings. Their number increased over time to a high count of over 60 birds seen at one time. They often sit high in the trees of the wooded property and then suddenly descend to sit in groups on platform feeders and to pick up fallen seed on the ground.

Over time, the evening grosbeaks have expanded their “territory” over the Northeastern USA, partly in response to increased planting of boxelders (Acer negundo, a type of maple) as shade trees. The seeds of the box elder are available throughout the winter and are a preferred food for these large finches.

Like numerous other bird species, evening grosbeak populations have declined steeply over time. Between 1966 and 2015, their numbers on the East Coast declined by 97%. Continued logging of forests in northern North America, avian diseases, aerial spraying of insects and climate change may all contribute to further reductions of this group of birds.

Researchers are now collaborating in an Evening Grosbeak Project that aims to compare flight calls, genetics and breeding behaviors of five distinctive sub-groups in this species. They are distinguished by the types of calls that they make and birders are asked to help out by submitting recordings to the eBird website.

It appears that Type 3 (Coccothraustes vespertinus vespertinus, the most irruptive of all five sub-groups) is the call type which has traveled to our area. It has a call that is similar to that of a house sparrow.

Some northeastern grosbeaks are now being tracked by the Project. An avian ecologist with the Pennsylvania Natural Heritage Program recently was able to band 47 birds so that sightings of them elsewhere can be reported. He also put a new model of solar radio tracking tags on 29 of the birds, which can help monitor their movements throughout their lifetime.

Evening grosbeaks can live well into their teens; the oldest banded individual was found when he was 16 years and 3 months. Perhaps some of those visiting us this year have been here before during food-poor periods up North. It will be interesting to see when they next decide to visit our area in the future and hopefully a few will visit me.

 

I’ve added some of the trees that tend to attract them, such as winterberries, maples and crabapples, to complement the junipers, pines and elms in my yard, so the welcome mat will be out!