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 – 2: nest-building

After courtship has taken place, the various bird species get down to the work of constructing nests for their upcoming broods. Even now in July, gray catbirds (Dumetella carolinensis) have been gathering up nesting materials, as have house finches (Haemorhous mexicanus) who have been followed around lately by the members of their first brood.

gray catbird P6147926© Maria de Bruyn res

house finch P7081079© Maria de Bruyn resThe sites they choose can vary considerably. Canada geese (Branta canadensis) tend to locate their nests at the edge of ponds if possible. In one case, a pair built their nest atop a beaver lodge.

Canada goose P4269282© Maria de Bruyn res

Canada goose P4070275 © Maria de Bruyn res

Ospreys (Pandion haliaetus) like to place their nests atop tree snags and will also use special platforms constructed by people for them. A radio tower or stadium lights, such as those at the right, will also do nicely, however.

osprey P5044393 © Maria de Bruyn res              osprey P6126775© Maria de Bruyn res

Northern cardinals (Cardinalis cardinalis) often choose shrubs and bushes; this one built her nest in a Japanese honeysuckle vine that I allowed to grow along the top of a fence surrounding my berry garden.

Northern cardinal 2G0A0652 © Maria de Bruyn res

Northern cardinal 2G0A0001© Maria de Bruyn res

Killdeer (Charadrius vociferous) seem to take the least effort in securing a spot for their nest. It is not uncommon at all to find them scratching out a very shallow depression in a parking lot, pathway or bare bit of ground. This killdeer put her nest on a patch of ground at the edge of a parking lot and, admittedly, it was not very obvious (Look carefully at the center of the photo).

killdeer eggs IMG_2885© Maria de Bruyn res

Nevertheless, people were walking across this patch of ground with their kayaks and canoes that they had just unloaded and the eggs were in danger, even if the parents did their broken wing display to try and lead people away from the area.

killdeer 2G0A8192© Maria de Bruyn res

I found a couple traffic cones and marked off the area, warning someone who had just parked nearby. Then I contacted the park rangers to tell them about it.

killdeer cones IMG_2887© Maria de Bruyn res

Fortunately, the rangers added a third cone and some tape to effectively cordon off the area.

killdeer IMG_5577 © Maria de Bruyn res

Carolina wren eggs IMG_1173© Maria de Bruyn resThe prize for weirdest nest sites will, in my humble opinion, always go to the Carolina wrens (Thryothorus ludovicianus). People in birding groups often post messages about these birds having built a nest under the hood of a car, in an old boot left outside, inside a little-used mailbox or on a door wreath or plant pot. I have a full-sized spare tire atop a tool cabinet and last year, the wrens laid eggs there.

This year, on one of my walks, I discovered wrens who were feeding their babies in a very awkwardly placed nest inside an old cable or wire box on a neighborhood light pole.

Carolina wren P5086279© Maria de Bruyn res     Carolina wren P5181735© Maria de Bruyn res

When I visited some time later, the nest was empty so the babies must have been able to fledge.

Carolina wren P5181745© Maria de Bruyn res

Many birds will use both tree cavities and nest boxes, depending on what is most convenient or available. Sometimes, they make their own new nest holes in snags, like this red-headed woodpecker (Melanerpes erythrocephalus).

red-headed woodpecker 2G0A0033© Maria de Bruyn res    red-headed woodpecker 2G0A0248© Maria de Bruyn res

Northern flicker P4217370© Maria de Bruyn res

This Northern flicker (Colaptes auratus) was very busy working on a new cavity as well. I followed her and her mate for some time but was never able to see them feeding nestlings as our area had several weeks of hard rain and the nearby lake flooded. I didn’t feel like wading through the lake to get to the snag to check up on them, even after the water had receded a bit.

Brown-headed nuthatches (Sitta pusilla) chose a snag that was usually in the water at the edge of Jordan Lake. The hole faced out into the lake so the fledglings were going to have to fly out and veer left or right immediately in order to get to a resting place!

brown-headed nuthatch P4175229 © Maria de Bruyn res

Eastern bluebirds (Sialia sialis) will use nest holes built by themselves or other birds in previous years.

Eastern bluebird P4070231© Maria de Bruyn res

Eastern bluebird P7070899© Maria de Bruyn resThis year, the Eastern bluebird pair who frequent my yard chose not to use their usually preferred nest box. I believe it’s because they could see me watching them and they don’t like that at all! If they see me with my camera, it doesn’t stop them from flying up to the feeder or sitting on a branch near the porch. If I point the camera toward the nest box, however, they stare at me in dismay, remain on branches near the box, and refuse to go in until I shift the camera away. They did come to my feeders multiple times daily to feed their first brood (one of whom is pictured at right), once they had fledged from a nest in someone else’s yard.

Eastern bluebird P7091193 © Maria de Bruyn resTo my surprise, a couple weeks back, the bluebirds chose to use a decorative nest box that I had bought for decoration. It hangs from a pole and sways in the wind and was not really sturdy. The roof began to let loose in the middle and the décor was curling up from the exposure to rain. But when I finally looked in the box when the parents were gone, I found four nestlings inside. They were pretty well grown already and I thought they might be fledging this past week. I didn’t see it, although I did watch a bit. Yesterday, I found one half of the roof on the ground and the nest was empty. I hope that the babies fledged and not that some larger bird plucked them out after the roof came off.

The materials used for nests can differ quite a lot. House wrens (Troglodytes aedon) make loose frameworks of twigs and the nests look pretty messy inside a box.

house wren 2G0A9598© Maria de Bruyn res         house wren P5181711© Maria de Bruyn res

They do seek out some softer materials with which to line the nest.

house wren 2G0A1982 © Maria de Bruyn res

Carolina chickadees (Poecile carolinensis) make beautiful cups of moss and line them with softer materials – plant fluff or hair from mammals that they find.

Carolina chickadee P3285249 © Maria de Bruyn res     Carolina chickadee IMG_8789© Maria de Bruyn res

Cliff swallows (Petrochelidon pyrrhonota) use mud to construct nests, often underneath bridges and rafters in more urban areas.

cliff swallow 2G0A3239© Maria de Bruyn res     cliff swallow 084A3656 © Maria de Bruyn sgd res

It is well-known that hummingbirds use spider web to help hold their nests together. Blue-gray gnatcatchers (Polioptila caerulea) are also known for doing this.

blue-gray gnatcatcher IMG_8085© Maria de Bruyn res

blue-gray gnatcatcher P4027629 © Maria de Bruyn res

I was surprised a couple years ago to find a nest-building Northern parula (Setophaga americana) also collecting spider web – it appears to be a popular construction material for the birds!

Northern parula 2G0A6727© Maria de Bruyn res

I will leave you with a couple photos from one of my favorite types of nests – that of the white-eyed vireo (Vireo griseus). The first time I saw one being built, I was quite surprised as the birds had chosen a low sapling only about 2 feet from a pathway. They weren’t fond of me watching so I took some photos and left. When I returned some days later, they had completed the nest. (The one below is a different bird.)

white-eyed vireo 2G0A5756© Maria de Bruyn res2

The nests are obviously well-made. This year, I came across an empty nest – also in a low shrub right next to a walking path. It has withstood strong winds, heavy rainstorms and other weather. Now it is a lovely decoration for walkers to see as they pass by.

white-eyed vireo P6125921© Maria de Bruyn res

Next up in the blog series: raising babies!

Some previous blogs about nesting can be seen here and here.

Big-beaked birds – lovely or laughable?

I don’t know how many of us would find a human being with an extremely large nose (e.g., even bigger than the face) and multi-colored head, facial and body hair to be beautiful or even attractive. Perhaps it would depend on the nose shape and which color combinations would be in play? But it is certainly a fact that many of us find big-beaked, multi-hued birds to be alluring and enticing, if not just plain gorgeous, magnificent and delightful to say the least.

Well, Costa Rica does not lack for a variety of big-beaked birds and I found them all appealing, each in their own way. Some were not completely colorful but had splashes of color, like the brown-hued Montezuma oropendola (Psarocolius montezuma) with its white bare patch on the cheek with a pink wattle underneath and mostly yellow tail feathers.

An unusual fact about this bird is that the males are generally twice as heavy as the females. They are called “colonial” nesters, meaning that the females build their pendulous nests (24-71 in/60–180 cm long) near one another in “colonies”. Unfortunately, their nest success is not great with only about one-third of colony nests resulting in a fledgling!

 

These oropendolas tend to forage in small groups in the tree canopies, searching for insects and fruit. Their love of fruit also brings them to feeding platforms, like this one set up to not only entice birds but also the tourists who want to see them. They seemed to especially enjoy papayas and watermelon.

The call that the males especially emit from their bi-colored black and red-tipped beaks is said to resemble water being poured from a bottle, bubbling and gurgling.

The chestnut-headed oropendola (Psarocolius wagleri) resembles the Montezuma species but is a bit less colorful with a pale bill. They are a bit smaller than the Montezumas and fly more quickly. Like their cousins, their broods in hanging nests are also threatened by giant cowbirds (nest parasites) and botflies.

 

We were lucky to see two toucans and a toucanet during our trip to Costa Rica this past year. We had a glimpse of a keel-billed toucan (Ramphastos sulfuratus) high up in trees on a cloudy day. Their large bill measures 4.7-5.9 in (12–15 cm), which is about one-third the size of their entire length! Their zygodactyl feet (two toes facing forwards and two facing backwards) help them balance on branches.

 

We got an up-close and personal view of a couple when we visited a hotel with an adjacent bird park and animal displays. A couple of these birds were in a large aviary, accompanied by two attendants who let people pose for photos with them. I just took photos of the birds and did not have a self-portrait done.

The second toucan that we got to see was the yellow-throated toucan (Ramphastos ambiguus), one of whom seemed to be posing for us during an early morning walk. They have an even larger bill than the keel-billed toucan, which ranges in length from 5.1-7.9 in (12.9-20 cm).

 

 

In 2018, I was able to photograph a couple that were flying by over a river.

     

 

The Northern emerald toucanet (Aulacorhynchus prasinus) is a smaller toucan that also sports a large beak in comparison to its head size. We saw one of these birds every morning at one hotel where we stayed as it was hanging out in trees next to our room cabins. It was often overcast, however, and it wasn’t easy to get a good photo; the same situation arose several days later when we saw one on another rainy day.

 

Luckily, that bird came down to a feeding station set up to attract birds for tourists. You can see its beautiful green body set off with a multi-colored bill that has a distinctive white band at the base.

 

Like other toucans, the toucanet will eat insects and lizards but it, too, has a real fondness for fruit meals, especially berries.

 

In contrast to the oropendolas, this bird’s calls resemble frog croaking and barking!

Unfortunately, it appears that these birds are popular as pets and they are taken from the wild to live in cages. They are popular because they can be affectionate and interact with their “owners” and they can learn tricks.

 

Going back to the bigger birds, Costa Rica has two aracaris, which are also members of the toucan group. They differ from other toucans in their sociability, often roosting in groups of several birds.

We did not see the fiery-billed aracari (Pteroglossus frantzii) during our August 2019 trip, but I had seen one flying by during a trip to Costa Rica in 2018.

It looks similar to the collared aracari but is distinguished by a bright red breast band and its bill is somewhat more colorful. It, too, is mainly frugivorous.

 

The collared aracari (Pteroglossus torquatus) was a frequently seen bird during our August trip through Costa Rica.

 

 

 

 

We visited several spots where people were earning tourist dollars by setting up feeding stations with plenty of fruit to attract a variety of birds. The aracaris were enthusiastic and voracious feeder visitors.

 

When the young aracaris are born, they are blind, naked and have short bills. Their feet also have specialized heel pads to help protect their feet from the rough nest floor. Not only the parents but also other birds help feed them for six weeks, at which point they fledge. The adults will still feed them for a time after they leave the nest as well.

These aracaris are interesting in that their large colorful bills also have a sawtooth pattern on the cutting edges. It can take up to a year for the young birds to develop the notches and color pattern on their beaks.

Now all these photos might give the impression that all the big-beaked birds are large in size, but this is definitely not the case. There are also medium- and small-sized colorful birds that tote around bills large in size when compared to their heads. Among the middle-sized range are two beautiful motmots.

We saw our first turquoise-browed motmot (Eumomota superciliosa) early one morning when it was still dark. A flashlight showed the bird sitting quietly in a tree as we made our way to breakfast. Oddly (to me at least), it didn’t seem very bothered by the bright light and just watched us as we drew near.

We later saw one sitting in a shady area alongside a road. They often perch on fences and wires as well, scanning the area for their diet of insects and lizards. They use their racketed tails for communication purposes, as part of a mating display or as a “pursuit-deterrent signal” to warn predators that they have been seen and will not be able to capture the aware birds. In Costa Rica, these birds have the nickname pájaro bobo (foolish bird) because they will allow humans to get quite near.

         

The broad-billed motmot (Electron platyrhynchum) is also an insectivore and has not been seen consuming fruit. These motmots are less studied than the turquoise-browed species; for example, it is not known how they use the tail rackets for communication.

 

The smallest bird in this account of the big-beaked avians is the rufous-tailed jacamar (Galbula ruficauda), which I first thought might be a large hummingbird. (Some hummers also have enormously large bills and will feature in a later blog.) They measure only 10 inches long (25 cm) with a 2-inch (5 cm) bill.

They are insectivores who will remove an insect’s wings before they swallow it. A surprising finding for me was that they nest in bare earth burrows. They do not keep the burrows clean and the nestlings do not lie down but remain standing so that they protect their feathers from accumulated debris!

On that surprising note, I wish my blog readers a wonderful start to the next decade and hope you all will have a great 2020 with good health, a comfortable living situation and as many hours enjoying our beautiful natural world as possible!

Costa Rican mammals, part 2 – those quite different from our Carolina wildlife neighbors!

Seeing mammals that we don’t get to enjoy during nature outings in the Carolinas was one of the treats of my Costa Rican trip. Although we spotted spider monkeys during our outings, it was the mantled howler monkey (Alouatta palliata) that we saw – and heard – most often. My first sighting of one was last year, when its white scrotum identified it as a mature male.

These primates eat mostly leaves (50-75% of its food), designating its diet as folivorous (new word for me!).

This low-energy diet means that they sleep and rest a lot – all night and about 75% of the day! They will supplement their leafy meals with fruit and flowers, and they get their water from bromeliads and holes in tree trunks.

Their large hyoid bones amplify the sound coming from their vocal cords so that their calls echo up to 3 miles (5 km) throughout the forest.

Interesting fact: if the howler is disturbed or irritated by humans, it will sometimes urinate or defecate on them, having surprisingly good aim from high in the tree canopy!

Another arboreal mammal that everyone in our group found endearing was the three-toed (brown-throated) sloth (Bradypus variegatus). These animals are apparently quite popular with tourists and often appear in logos and signs. An orphaned sloth was brought to one hotel where we stayed; the staff let the youngster go up in a tree in the courtyard where we could see it.

     

I had seen (and touched) a sloth in a friend’s back yard in Bolivia once (right); seeing another one close-up outside a zoo was a new treat. I love how they move in slow motion. Their sluggish movement is a result of their diet – just like the howler monkeys, they are folivorous and conserve energy as a result of their mostly leafy diet.

 

That slow movement and the fact that they cannot walk on all fours, unfortunately can also be the cause of their undoing. Their movement on the ground consists of dragging themselves forward by their forearms and claws. Our guide told us that when they cross roadways in that position, drivers may not notice them on the pavement until it’s too late to avoid them. ☹

An interesting fact is that their rough hair eventually comes to harbor various organisms, including cockroaches, beetles, moths and algae. So picking them up and holding them is perhaps not advisable – both for the human who can get insects all over them and for the sloth, who can get upset by being held. (The sloth I touched in Bolivia, below, was at the base of a tree and when I put my hand on its chest, it made no movement but I could feel its heart rate suddenly increase rapidly, so I backed off!)

 

Another interesting behavior – once a week, the sloths leave their trees to defecate on the ground. At this time, they become vulnerable to predators. (The sloth in my friends’ yard unfortunately did this and was killed by a neighborhood dog.)

 

On the ground, a slender dark mammal that frequents hotel gardens, people’s yards and nature reserves is the white-nosed coatimundi (Nasua narica). These mammals are related to raccoons and people in Costa Rica will tell you that they are Costa Rican raccoons.

 

Coatis, as they are popularly known, travel both on the ground and in trees, although I only saw one arboreal individual. They usually spend the nights in trees and then come down to look for food, which includes small vertebrates such as mice and lizards, eggs, snakes, insects, carrion and fruit – a varied diet, for sure!

The coati below was busy at the side of a mountain road we walked; it was unclear to me what it was doing. There was obviously another animal there and at first, I thought it was a young coati, but I don’t think that was the case. I now wonder if another mammal had died and the coati was investigating it as a food source.

 

They do not appear to be very wary of humans; this one passed by fairly close in a wooded area. Apparently, people will feed coatis strawberries along roadsides, which will undoubtedly make them less wary of humans. This coati might have been a male as they are solitary except for mating season when they will join a female group for a time.

Another ground-dwelling mammal we saw on multiple occasions in different areas was the Central American agouti (Dasyprocta punctata). This rodent plays an important role in the forest as it is a seed disperser. Like squirrels, the agoutis bury caches of seeds and nuts for lean times; when they do not re-visit a storage area, the seeds and nuts may germinate to create new trees.

 

The agoutis eat other foods as well, including leaves, roots and fruit. They will sit on their hind legs and hold the food in their front paws to dine.

These cute animals mate for life; the young are unusual in that they are active right after birth. The mother takes them to nest sites dug by other animals so they can claim their own home burrows! The young then line their home with leaves and twigs.

It is worth noting here that the Costa Ricans are protecting their ground mammals and all other wildlife. The country was the first in Latin America to ban sport hunting in 2012; it is also forbidden to keep, import or export wildlife for the pet trade.

And finally we get to the smallest mammals we viewed during our August trip. Last year, our group had been surprised to find that a group of bats was flying into a hotel’s outdoor restaurant to roost each night. The staff accommodated the creatures, which they listed as two-lined bats. After reading about Costa Rican bats, I think these might be lesser white-lined bats (Saccopteryx leptura). It was interesting to see how they would hang by one leg as they engaged in some grooming.

This year, we came across a small group of similar-looking bats roosting under a bridge. They had white lines down their backs but appeared to be long-nosed proboscis bats (Rhynchonyceteris naso). Their colonies often number 5-10 individuals.

One of our most interesting walks took place the day after our bridge sighting. We were visiting a self-taught local artist named Cope, in La Union, Guapiles. He created a wildlife viewing site around his home where he welcomes tourists to see hummingbirds and other avians. He offered to take us into the nearby forest to find a particular owl (coming blog!), as well as a couple species of bats and some interesting amphibians.

While we may be used to thinking of bats living in caverns, various species in the rain forest have found other roosting sites. The tent-making bats (Uroderma bilobatum) create a home by biting through the middle vein of a large leaf so that the sides droop down and form a hanging shelter. The structure is recognizable and after Cope found us a couple tents, members of our group knelt or hunkered down so we could peer upwards at the sheltering mammals.

 

At one site, after photographing the bats, I unfortunately stumbled backwards after taking a photo; I startled the bats, who took off in haste. Apparently, it is known that they spook easily since the slightest movement of their leaf could indicate that a predator is approaching. Cope fortunately located another tent so that the other group members could peer upwards at the creatures.

Our guide was kind enough to use people’s cell phones to take photos of the little bats.

At another tent, it turned out that adorable Honduran white bats (Ectophylla alba) were roosting. Of the approximately 1300 known bat species, only six have entirely white fur.

These bats are frugivorous, with one fig species being a preferred food.

The Honduran white bats are unique in being able to convert lutein into a form that better helps protect the retina and it is speculated that understanding how they do this could be helpful in the treatment of macular degeneration.

Our final bat species had a different type of residence – a termite mound, which may be abandoned or actively harboring termites. I believe that the species we saw was the pygmy round-eared bat (Lophostoma brasiliense), an insectivore although it will also eat fruit. Their daytime roosting site is maintained by a resident male bat, who prevents termites from repairing the cavity made by the bats. Seeing these nocturnal mammals in an unexpected home was truly an interesting way to conclude our bat-watching outing.

 

Many thanks to Nan DeWire and Ylva Byars for letting me include photos they took in this blog. After a foray into North Carolinian wildlife in the next posting, it will be back to Costa Rica to take a look at the woodpeckers there – and elsewhere!

Summer hummers – entertainment for free: part 1

 

When a hummingbird other than a ruby-throated hummingbird (Archilochus colubris) is seen in the Triangle area of North Carolina, it is listed as a rare bird on the Cornell Lab of Ornithology listserv. One year, I did have a chance to see a buff-bellied hummer visiting in a nearby town though; another year a rufous hummer frequented my own feeders in the winter. Mostly, however, it is the ruby-throats who take up residence at my address, which is just fine as these feisty tiny birds provide loads of entertainment.

 

During a trip to Quebec earlier this year, we also saw ruby-throated hummingbirds there – early arrivals during the spring migration.

 

A few years ago, one of my blogs focused on their preening and cleaning, so this time I’ll mostly feature some of my favorite photos of them taken this summer in various places. (When looking through the shots, I had a LOT I liked, so this is now going to be a 2-part blog!)

At Sandy Creek Park in Durham, one female hummer had made a coral honeysuckle (Lonicera sempervirens) one of her preferred dining spots.

 

 

A butterfly garden featuring blue-black sage (Salvia guaranitica) and bee balm (Monarda) also attracted her and some other hummers.

 

One female found the bee balm to be a good place to rest, understandable since these bundles of energy have a high metabolic rate. Their hearts beat up 1260 times per minute and they take about 250 breaths per minute even when they are resting! Taking a few sips while remaining perched has to be a welcome luxury.

 

 

 

 

The hummers’ main wing bone, the humerus, is adapted to hovering flight and they have very large deltoid pectoral muscles relative to their size.

 

 

Male birds produce sperm that flows through the vas deferens (sperm duct) to the cloaca. When they mate with a female, they transfer sperm by touching the tip of their cloaca to that of the female; they do not have a penis. Females only have a functional left ovary; the right one atrophies early in her development, which allows her to avoid the extra weight of a second ovary and makes her lighter for long migratory flights.

One big treat for me this year was finding two ruby-throated hummingbird females tending a nest, the first time I had been able to spot this.

 

Later, I was able to take a quick photo of one female collecting cattail fluff with which to line her nest.

Even when several ruby-throats are frequenting an area, the (temporary) coloring of their feathers can help distinguish them. This young male had a few olive-green dots under his eye and a bit of white on the crown of his head.

 

A somewhat more mature male has a little white patch behind his red gorget.

 

They are all little beauties! Second part of this blog is coming up and then on to Costa Rica!