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!

Costa Rican mammals, part 1 – those similar to our Carolina wildlife neighbors!

While the trip I took this past August to Costa Rica was mainly focused on birding, our guides fortunately were also quite willing to stop and look for mammals, amphibians, reptiles and insects – people after my own heart! Here I’ll focus on some of the mammals we saw, starting in this 2-part blog with those that were familiar.

Fellow traveler Nan especially was drawn to the canines we came across – there wasn’t a dog (Canis) that she was unwilling to pet!

 

And they often were very cute.

 

As we drove from one destination to another, it was not uncommon to see light-colored cattle (Bos taurus) grazing in fields. It turns out that about 75% of the country’s cattle are found in Guanacaste province (where we started our trip) and that the Brahman breed is the one commonly raised for the meat industry.

I saw mostly cows, but during a visit to southern Costa Rica last year, we also saw a laid-back steer.

 

There were horses (Equus caballus) grazing in some fields and mountain valleys.

Everywhere we went, there were squirrels scurrying about on the ground, in trees and at feeding stations. The most commonly seen squirrel in the country is the variegated squirrel (Sciurus variegatoides), which varies in color from gray hues to dark brown colors.

  

This species spends most of its time in trees and does not hoard food.

 

Their main dietary selection consists of various seeds, although they also eat acorns, fruit and insects.

   

Another cute rodent is the red-tailed squirrel (Notosciurus granatensis), which is usually found in the cloud forests and wet/humid areas.

Although in some places, people warn against feeding mammals, we saw a red-tailed squirrel enjoying fruit at a restaurant that attracts tourists with its plants that attract hummingbirds.

 

While we do have wild boars in some mountainous North Carolina counties, as well as feral swine in Eastern coastal areas, we will not see collared peccaries (Pecari tajacu) roaming our forests and woods. They share some characteristics of the pig family but are not classified as pigs.

They are both carnivorous and vegetarian, even eating tulip bulbs, which are poisonous for humans. It’s said they usually ignore humans and that was the case for this peccary, which paid us no mind as it plodded about the gardens in one reserve.

 

Our final, at least partly familiar, mammal was observed near the restaurant of a hotel where we stayed. We were lucky to see it since these animals are both arboreal and nocturnal. Fellow birder Ylva got a nice photo of the visiting Central American woolly opossum (Caluromys derbianus). Not only is this marsupial a real cutie, it is also a nectar feeder, pollinator and seed disperser so that we got to see a species that fulfills multiple roles in its rain forest habitat.

Next up – the mammals we won’t see in North or South Carolina (yet).

Costa Rica – varied landscapes and fabulous flora. Part 1 – gingers and bromeliads

Our trip to Costa Rica in August this year took place during the rainy season, making for some challenging wildlife photography but giving us good views of lush vegetation everywhere we traveled. Our journey went through Guanacaste province with dry scrub, salt flats and mangrove swamps, the Monte Verde tropical cloud forest, the area around the Arenal volcano, and Caribbean lowland rain forests.

We traveled along highways lined with rocky walls featuring drainage pipes to help prevent landslides, as well as some narrow mountain roads with very deep and steep drop-offs alongside our driving lanes – at those times, I wasn’t necessarily looking out the window, especially when we had a nerve-wracking encounter on a narrow road with another vehicle requiring some backwards driving by our well experienced driver!

At one point we visited some salt flats to get a view of some water-loving birds such as plovers and sandpipers.

Other times, it was a pleasure to gaze out at the passing landscapes featuring forests, plantations, small settlements and homesteads, lush valleys, waterfalls and rivers.

 

Our arrival in Costa Rica immediately drew attention to the need to protect plants as the airport had numerous signs warning travelers about bringing in Fusarium wilt, a disease that can wipe out banana plantations within a short period of time. Along roads and in nature reserves, the banana plants (Musa) fortunately looked healthy.

   

While I enjoy gardening and am slowly replacing lawn with native plants around my house, I’m no horticulturist or botanist; identifying plants is a challenge for me. But I hope to show you a little here of the beautiful vegetation we saw in a two-part blog. And perhaps some of my fellow travelers may be able to identify some of the plants pictured (like those below) or correct anything I’ve mis-identified.

 

Guanacaste province, where we started out, has dry terrain as this region does not receive much rain and has consistently high temperatures. This contrasted with the tropical cloud forest in the Monte Verde and Santa Elena Cloud Forest Reserves where we spent time. Rain gear and umbrellas are a definite boon when spending many hours walking outdoors in these areas.

These forests may be chilly with temperatures at night sometimes falling to 55°F (13°C). The humidity can be close to 100% and we had to change our itinerary a couple times to avoid slick mountain roads when some storms came inland.

The tropical rain forests see the most rain and the temperatures usually range from 70˚F (21˚C) to 93˚F (+34˚C). We were fortunate to visit the La Selva Research Station owned by the Organization for Tropical Studies which has many species of plants and ants. Less than 10% of our world is (still) covered by tropical rain forests, but scientists have found that the rain and cloud forests are home to about 50% of the earth’s terrestrial species.

The natural areas where we stayed and visited offered up a wealth of wonderful flowers and plants. The gardeners among us especially appreciated the variety of foliage and colors. It wasn’t always easy to figure out which plants we were seeing, especially because many of the gardens and reserves also feature tropical plants from other regions of the world. They did put signs by some plants but not all of them; of course if your area is home to over 2000 plant species, as in La Selva, keeping signage up to date would be an endless task.

African blue butterfly bush (Clerodendrum ugandense)

Bougainvillea

As mentioned, many gardens and reserves in Costa Rica feature plants that originated in other world regions. One of my favorites, true ginger (Zingiber spectabile) is one of these. It is commonly known in the Western hemisphere as beehive ginger. The tubular bracts fill with rainwater and emit a ginger-like fragrance, which attracts bees, butterflies and hummingbirds. The bracts start off yellow in color and eventually achieve a wonderful red hue. The actual flower is a white petal protruding from the bract.

This type of ginger is promoted as a decorative cut flower as the bracts and flowers can survive long after having been cut. It has been used to treat illnesses in Indonesia and an academic study has indicated that this plant has antimicrobial properties; it also contains an enzyme that could possibly be effective in the treatment of colon cancer.

Other ginger plants were also lovely.

 

Red ginger (Alpinia purpurata)

 

Torch ginger (Etlingera elatior) – one of my favorites!

 

 

Indian head ginger (Costos woodsonii) at left.

There are about 2500 species of bromeliads around the world and Costa Rica has its fair share. These plants can use water more efficiently than other plants because they have a specialized form of photosynthesis.

 

 

 

Bromeliads (Tillandea cyanea at the right)

The tank bromeliads feature leaves that hold water at their base in a kind of reservoir; the largest ones can hold up to two gallons of water. We were fortunate to see blue dacnis birds (Dacnis cayana) enjoying baths in a large epiphytic bromeliad. The reservoir in this air plant must have been a nice bathing spot since a line formed of birds awaiting their turn.

 

A flower that is probably familiar to US residents who have visited botanical gardens it the Angel’s trumpet (with white blooms, Datura arborea; with pink and yellow hues, Datura sanguinea). There is also a Brugmansia arborea, a tree with white blooms, that has been declared extinct in the wild. The Costa Ricans call this plant the Reina de la Noche – Queen of the night.

 

One newspaper article touted this plant as a form of aromatherapy because it has a fragrant and “relaxing” scent. However, my Costa Rican friend Esmeralda warned me that it is a highly poisonous plant and this has been confirmed.

The flowers below might have been Anthurium species.

 

                       Next blog – the heliconias!

“Wattle” I do to get a better photo of you?

In mid-August 2019, it was my privilege and good fortune to participate in an interesting, engaging and VERY fun “Birding Plus” tour in Costa Rica thanks to a great roommate, Nan, knowledgeable guide and tour organizer, Steve and Sherry, and group of fellow travelers (Ann, Art, Bill, Gordon, Len, Tom and Ylva). My next blogs will mostly focus on the birds, amphibians, mammals and insects we were fortunate to see there. The photos are not all great as taking shots in the rain and dark cloud/rain forests was challenging for multiple reasons. But they will give you an idea of the fascinating and beautiful sightings we had. (Clicking on photos enlarges them; then back arrow.)

One of the most difficult birds to “capture” in a good photo was likely the one about which I was most excited, the three-wattled bellbird (Procnias tricarunculatus). This species, which also lives in Honduras, Nicaragua and Panama, only breeds in the mountains of Costa Rica. These bellbirds are known to be shy, secretive and elusive as they remain mostly in the dense, high canopies of the forests. They apparently prefer to perch on uncluttered branches that are 33-72 ft (10-22 m) high and 0.98-2 in (25-50 mm) in diameter.

The males usually sing from March through June, so we were lucky that some of them were calling out in mid-August. Here we see a couple digiscoped photos of a male bird. The females look very different with olive coloring and a streaky yellow breast (we did not see a female). They are quite different in size, with males in one study having a mean wing length of 6.5 in (165.5 mm) compared to 5.7 in (145.1 mm) for the females.

 

 

The common name for these birds comes from the sound they make. In some articles, it is described as a 3-part song. To me, it sounded like they first made a high-pitched brief screech, squeak or whistle sound and then a deeper call.

 

Others have described their calls/songs as a “boink,” “bonk” or “Hee-aahh” sound. In any event, they obviously work at producing the sound. As we watched, “our” bird would open his mouth very wide, so that you could see the white and black lines surrounding the bill.

He seemed to be breathing in plenty of air as he sat there silently for a while. You could see his neck getting ridges, which I assumed was due to the oxygen he was gathering and holding to be expelled in the call. (This turned out to be a correct assumption according to one study!)

Then, he moved his head up and down a bit and you knew the sound was coming. It is unmistakable once you have heard it as in this brief video that fellow traveler Ylva made.

It is said that the bellbird’s sound is one of the loudest avian calls, audible to humans who are more than 0.5 miles (0.80 km) away. The calls and songs are not instinctive – the birds learn the calls and there are different “dialects” among the birds from different areas! One bird studied in Costa Rica could perform the song/call repertoires of Talamanca and Monteverde – in other words, he was bilingual!

 

Research has also shown that immature male bellbirds not only take 6 years to achieve their full adult plumage but also to perfect their entire song repertoire! Kroodsma et al. also note that: “Males appear to be highly attentive to the nuances of songs produced by their competitors, as both immatures and adults visit each others’ display perches, listening there for up to several minutes at a time.”

The other really striking characteristic of this species is the three wattles on the male’s head which begin growing when he is 6-12 months of age. One dangles from each side of the bird’s mouth and one is affixed to the base of the upper bill.

The wattles have been described as “wormlike”. Nan and I thought they looked a bit like hair-braids and on the flight home I sat next to a woman who had three braids ending in a point with interwoven gold thread that immediately made me want to give her the nickname “Bellbird”. (I didn’t tell her that though.)

The wattles are about one-third of the bird’s size (9.5-12 in or 25-30 cm). They cannot be controlled by muscles or made rigid, but they can be extended in length up to 3.9 in (10 cm) when the bird is interacting with others or singing.

The birds are frugivorous (eat only fruit) and prefer wild avocados (Lauraceae). They play an important role in the tree’s seed dispersal.

 

Due to habitat loss and hunting, the numbers of the three-wattled bellbird have declined to about 20,000 individuals and the International Union for Conservation of Nature (IUCN) has declared its conservation status to be vulnerable. They obviously inspire artists in Costa Rica, however, as witnessed by a mural at a restaurant where we stopped for lunch.

 

 

After three blogs in quick succession, I’ll now take a break to process and sort some more photos from Costa Rica to share with you. In the meantime, bye bye from the bellbird!

Further information

Quebec chronicles – brown and white beauties in abundance!

Several years ago, I saw my first chestnut-sided warbler (Setophaga pensylvanica) during breeding season in the mountains of North Carolina. It was a somewhat fleeting sighting but long enough for me to recognize the male’s beauty. My next sighting was a couple years ago when a pair stopped by a local creek during their south-bound migration in the fall. They were still attractive, but I had fallen for their mating season colors. What I didn’t know then was that when they reached their winter destination in some Central American area, they would be likely associating with the same birds with whom they had spent previous winters foraging.

Lucky me, therefore, when I noted that many chestnut-sided warblers were part of the spring migratory crowd in Quebec a couple weeks ago. I saw them in at least five sites and was able to get some nice photos of these beauties.

The Cornell Lab’s All About Birds website advises: “Stay around clearings, road edges, or other disturbed sites with young deciduous trees to find Chestnut-sided Warblers.” They did indeed appear in such places, looking for insects.

 

They appear to really like early successional deciduous habitats, e.g., terrains affected by logging, fire, storms and flooding. Clearing of people’s land around their houses may also qualify as a habitat-forming place for these little birds. We also discovered that these colorful warblers look for food among stones, rocks and boulders along bodies of water.

 

At a small park alongside an inlet of the St. Lawrence Seaway, a chestnut-sided warbler was hopping along the rocky shore seeking caterpillars.

 

  

He also flew out over the water from time to time in order to catch insects on the fly.

At the St. Irénée quay, a species mate was popping in and out among the large boulders on either side of the pier.

Seeing these beautifully colored birds as they hunted for insects was quite enjoyable. The Rev. Leander S. Keyser, who attended the 1896 World Congress on Ornithology, remarked that the chestnut-sided and blackburnian warblers were like “a sonnet in feathers – lightness of air and sunshine embodied – rhythm caught in a living form” – what a beautiful way of describing them!

 

 

Besides the chestnut-sided warbler, I saw another species which I’d seen with more muted colors in North Carolina – the bay-breasted warbler (Setophaga castanea). In the autumn, they have a yellow-green head and only slight chestnut-colored wash on their flanks; they look very similar to blackpoll warblers during that season and winter.

 

 

When I saw their breeding plumage in Quebec, it was a real surprise – and a most pleasant one! The bay-breasted warblers immediately became one of the birds I’ve most enjoyed seeing. And as I saw more and more during the week, I never tired of watching (and photographing) them!

 

During breeding season, these birds eat many more insects than fruit and they were very busy gleaning in the conifers.

In the spring, they specialize in seeking out spruce budworm moth (Choristoneura fumiferana) caterpillars. It was shown in one study that the bay-breasted warblers ate more than 13,000 budworms per 2.5 acres (one hectare) in a period of 41 days. These moths produce larvae that can decimate spruce and fir forests in Canada when their numbers increase greatly. The populations of bay-breasted warblers then fluctuate in conjunction with those of the budworms, which have an “outbreak” every 30-40 years.

In 2004, Boulanger and Arseneault studied this phenomenon and concluded that: “data suggest that outbreak frequency has remained quite stable, with a mean interval of about 40 years between the midpoint of successive outbreaks since the mid-16th century.” It would be interesting if another study could be done to see if the outbreak frequency is changing with climate change. The current population explosion of the budworms began in 2006 and could last until 2021; the government of Quebec is spending $30 million this year to eradicate the moth so the warblers may lose a food source. Their numbers may therefore also decline as a result.

While the fluctuations in their numbers have risen and fallen together with the spruce budworms, their summer habitats may be affected by human interventions. It is estimated that only 4% of these areas are stable so conservation efforts should take this into consideration, especially because their global population numbers have fallen about 74% since 1966.

As these birds forage on tree branches, they tend to move more slowly than some of the other warbler species, taking their time to seek out juicy tidbits. In addition to caterpillars, they eat beetles, flies, moths, leafhoppers and grasshoppers.

The female bay-breasted warblers can be distinguished from their male counterparts by the fact that they lack the black face mask and have lighter bay coloring.

Both sexes seemed to be fairly comfortable with me watching them. They seemed much less shy than some other species of birds. To my complete delight, of course!

 

An interesting observation is that they tend to like foraging on lichen-covered branches.

In contrast to some of the other warblers, they tend to build their nests in the mid-level tree canopy; that is also where they do a lot of their food hunting. However, as my walks in St. Irénée showed, they are not averse to foraging on the ground!

 

   

Since they mostly breed in Canada and spend their winters in Central and South America, seeing them in North Carolina during migration is a treat. Interestingly, the adults tend to migrate along routes west of the Appalachian mountain range and immature birds often migrate along the Eastern US seaboard and coastal areas.

 

These birds of waxing and waning populations have inspired poets and I can see why. Seeing them in their breeding plumage in Quebec was a wonderful gift. I hope to see them there again one day as they have joined my list of special species that I love. 😊