Tuesday, August 22, 2017

Golden-hooded Tanager

Golden-hooded Tanagers are in the genus Tanagra, bright and varied tropical birds. About ten species are found in Costa Rica. This species occurs from southern Mexico to Columbia and Ecuador. It favors jungle edges, clearings and gardens. This tanager seemed to be common almost everywhere we visited in Costa Rica.

The closeup photos on the bottom was taken in the eastern part of the country on the last day of our trip. The first picture was taken on 2 August, the first full day of our travels. A pair of Golden-hooded Tanagers hopped about in front of a large, grass, domed nest. The female entered and exited from a hole in the side of the nest. What is strange is that this tanager’s nest is supposed to be an open cup (Cornell). It seems unlikely that these tanagers were using some other bird's nest. Possibly they were foraging for food in another species's nest.

Monday, August 21, 2017

Firetails

Two firetails were stunning dragonflies at the Villa Lapas frog ponds. (I use the word dragonfly to include damselflies.) Hyacinth Firetails (Telebasis levis) were abundant—and well named in English by Dennis Paulson, since water hyacinths clogged the small pools.

I was startled to find a firetail with striped sides. I called to Dennis, who identified the new damselfly as a Striped Firetail (Telebasis filiola). These two, in a “wheel” position—the male grasping the female’s neck and thus guarding her from competitors, while the female collects the male’s sperm—were the only Striped Firetails we saw. Both species range from Mexico to Panama.

Sunday, August 20, 2017

Cherrie's and Passerini’s Tanagers

Walking through the grounds of the Villa Lapas eco-lodge in western Costa Rica, we were delighted when an all-black tanager perched on a tree branch in front of us. Then the tanager spun around and displayed its scarlet rump. Aside from being beautiful, Cherrie’s Tanagers are taxonomically interesting. They used to be named Scarlet-rumped Tanagers. But these birds were split into two species— Cherrie’s along the Pacific coast of Costa Rica and Panama and Passerini’s on the Caribbean cost, from southern Mexico to northeastern Panama. 
The males of the two species are virtually identical. The last photo is of a Passerini’s Tanager taken later in our journey in eastern Costa Rica. The dull female Passerini’s Tanagers are actually easier to tell apart. They are brighter in the east than in the west. The two species, however, have different gene sequences. They do not hybridize, even in the only place where they come into contact in northwestern Costa Rica. (Since the males are so difficult to tell apart, I am not sure how ornithologists’ determined that the species don’t interbreed.) Cherrie’s Tanagers are named after George Cherrie, who explored the Brazilian River of Doubt with Theodore Roosevelt in 1913. Passerini was an Italian entomologist who lived in the early 1800s.

Saturday, August 19, 2017

Black Dasher

So far I am still posting about our first full day in Costa Rica, 2 July 2017. This dragonfly is a male Black Dasher (Micrathyria atra). This species occurs from Mexico to northern Argentina. We found several at the frog ponds at the Villa Lapas eco-lodge. The dasher appeared to watch us leave the ponds as we made our way back across the lodge grounds, searching for dragonflies and birds.

Friday, August 18, 2017

Familiar Bluet

On 11 August, Erika and I attempted a stroll in the St. Olaf College Wildlands. We did not last long before being beaten back by hoards of mosquitos—far worse than anything we experienced in Costa Rica! We managed to take one photograph along the trail—a Familiar Bluet.

Familiar Bluets are common, but local, damselflies across much of North America, south through Central America to northern South America. I have encountered them in south Texas. Curiously, this record is my first from Minnesota. We may be near the northern edge of their range. Others have recorded this species from the campus.

The species is similar to a number of other species. Note the projections on the back end. The little spines are triangular and almost as long as the last abdominal segment. Thanks to Jim Johnson for helping me with my identification.

Thursday, August 17, 2017

Harnessed Tiger Moth

On 11 August 2017, I was strolling dutifully behind Erika in the lumberyard of our local Menard’s when a striking moth caught my eye. I took this photo with my cell phone. It is a tiger moth. According to bugguide.net, at least four species of tiger moths and they are difficult to tell apart. The only way is to dissect and check out the genitalia. Clearly I did not do that, and I wonder if the moths carry microscopes with them when they go out to mate. 

I suspect this moth may be a Harnessed Tiger Moth, found from southern Canada to Florida, and west to Texas and South Dakota. The larvae feed on clover, corn and dandelion (Bugguide).

Wednesday, August 16, 2017

Eastern Kingbird

The local Eastern Kingbirds have brought off this year’s clutches. This first photo was taken on 7 August 2017, in Rice County in the Carleton College arboretum. This young bird seems to be contemplating its upcoming journey to South America. The second photo is of a recently arrived kingbird taken last May in the county. I have been experimenting with a new photo development program, Topaz Studio. I am pleased with the results. The app replaces Adobe Photoshop. If for no other reason, it is worth trying because the basic program is free.

Tuesday, August 15, 2017

Proboscis Bat

More bats in the Villa Lapas belfry. Proboscis Bats live in groups of up to 10, sometimes more. They have regular feeding areas, preferring small ponds like where we searched for dragonflies and frogs. They form harems and breed all year. These bats are found from northern South America north to southeastern Mexico.

Monday, August 14, 2017

Tent-making Bat

On 2 July 2017 alongside the Frog Ponds at the Villa Lapas eco-lodge in western Costa Rica, we found a Tent-making Bat hanging in a garden bush, These bats make their own abodes. The bats chew the ribs and veins of plants until the leaves fold over, creating a tent. On the plus side, this behavior means that the bats do not have to search for shelter in caves (which can be uncommon in the jungle) or other cavities in trees or in buildings. The disadvantage is that the leaves wither and die, and the bats have to make new tents every couple of weeks. One consequence is that Tent-making Bats tend to be more nomadic than more typical bats. (Wikipedia).

Look in the bat’s ears. The shiny, brown structure in each ear is not an eye, but a tragus. The tragus is a fleshy structure that aids bats in echolocation. The tragus collects sound from behind the bat. The result is that a bat has enhanced perception of its surroundings. The black eyes are further down the head nearer to the bat’s nose.

Sunday, August 13, 2017

Hourglass Frog

Hourglass Treefrogs, or Dendropsophus ebraccatus, are tiny, yellow frogs. They are Central American amphibians and are tolerant of ecological disturbance. They differ from other frogs (and, perhaps, all other vertebrates)—they can lay their eggs in the water or on land. If little shade exists, they go for the water. With shade, they lay their eggs on land. When in the water, the tadpoles are eaten by dragonfly nymphs. To escape the dragonflies, the frog larvae can change their tail color (Wikipedia).

Saturday, August 12, 2017

Red-eyed Tree Frog

One of the many highlights of our Costa Rican tour were the small, artificial ponds at the Villa Lapas eco-lodge. We visited both during the day and at night. I hoped we would see Red-eyed Tree Frogs. They are often used as icons for rainforest preservation. They are found from Mexico to Colombia. You can find them on both slopes of Costa Rica. Frogs from the Pacific Coast have yellowish sides. Those from the Caribbean side, like the one in the second photo, sport blue sides.
These frogs flash their red eyes to startle predators. The frogs are not poisonous, They depend on their green backs for camouflage. Mating Red-eyed Tree Frogs call during the rainy season and also shake branches to attract their mates.
During amplexus, like in the third photo, the female carries the male on her back, sometimes for several hours, as she lays her eggs. The female glues her eggs on pond leaves (Wikipedia). Finally, the last photo is of frog eggs laid in such a manner. No guarantee, however, that these belong to Red-eyed Tree Frogs.

Friday, August 11, 2017

Carmine Skimmer

Dennis Paulson was disappointed in the relative lack of dragonfly habitat at the Villa Lapas eco-lodge. Enough species, however, flitted about to keep us entertained. This Carmine Slimmer defended a small puddle in a roadside tire track. The dragonfly zipped back and forth, making photography nearly impossible. The species is known to be an aggressive defender of its territory, which can be up to 30 feet long (Paulson).

“You know,” said Dennis, “we could provide it with a perch.” Dennis stuck a stick into the mud. Within a minute, the skimmer landed in front of us.  Carmine Skimmers range into south Texas, where their range is rapidly expanding. A couple of Arizona records also exist. This species ranges south to Argentina.

Thursday, August 10, 2017

Bare-throated Tiger-Heron


After watching the kingfisher of the last post, Erika turned on the Villa Lapas bridge and explained, “That looks like a Tiger-Heron!” A Bare-throated Tiger-Heron to be exact. You can see that the heron’s throat is not feathered. This tiger-heron is the only one with a bare throat.

We encountered Bare-throated Tiger-Herons throughout our Costa Rica trip. They were especially common in the one mangrove swamp we visited. I found their plumage to be remarkably variable. This individual seemed remarkably strikingly plumaged.

Tiger-Herons eat fish, frogs, crustaceans and insects, probably whatever they can catch. Although we saw them during the day, the species by nature is crepuscular or nocturnal. Bare-throated Tiger-Herons are found from the Mexican lowlands south through Central America to northernmost South America. Apparently there is one record from southern Texas (Handbook of Birds of the World).

Wednesday, August 9, 2017

Ringed Kingfisher

A river runs through the grounds of the Villa Lapas eco-lodge. A tall, wide bridge connects two sides of the hotel accommodations.  Here, on 2 July 2017, perched one of our first birds at the lodge. A Ringed Kingfisher patiently watched for fish. At first the bird was hard to identify—it faced away from us. Only when the bird turned sideways could we see this bird’s massive bill. In the last 40 years, Ringed Kingfishers have expanded their range into Texas. Usually they are found from the Mexican lowlands, through Central America, and south across much of South America.

Unlike Belted Kingfishers, Ringed Kingfishers seldom hover before plunging for their prey. Instead they sit patiently, sometimes for hours. They mostly consume fish. On the other hand, like our Belted, Ringed Kingfishers depend on high, dirt banks in which to excavate their nests. The absence of such landmarks can limit these birds’ occurrence (The Birds of North America).

Tuesday, August 8, 2017

Villa Lapas

We spent the next three nights near the Pacific Coast of central Costa Rica at Villa Lapas. This eco-lodge is a cluster of cabins in the rain forest adjacent to Carara National Park. The forest here is the northernmost extension of the Pacific rainforest remaining in Costa Rica. The rooms are comfortable, despite the forest attempting to colonize the cabin roofs. The cabins were air-conditioned. Not that I am complaining, but air-conditioning caused our camera equipment to fog over for a half-hour as we emerged every morning. I am sitting on our porch waiting for my lenses to clear.
The grounds were gorgeous, and full of birdlife. A clear stream—at least until a night of torrential rains— runs through the grounds, and the hotel maintains a couple of small pools, ideal for searching for frogs and dragonflies. Dennis was disappointed that previous floods had taken out other pools. Overall, we felt that the hotel offered a good introduction to Costa Rican dragonflies and birds. The nearby National Park allowed us to venture deep into the jungle. Lapas, by the way, is a word for macaw. We saw Scarlet Macaws every day.

Monday, August 7, 2017

Dusky Dasher

On the far side of the Rio Tarcoles bridge, on 2 July 2017, we found a female Dusky Dasher (Micrathyria schumanni). This species is found from Mexico south to Venezuela, and not in the United States. We got excited because our fearless leader, Dennis Paulson, did not immediately provide us with a name. After our return home, Dennis researched and concluded that this dasher is the only one whose females have an almost pain, brown abdomens.

Sunday, August 6, 2017

Square-spotted Dasher

Despite the Tourist Police attempts to keep our being devoured by crocodiles on the Rio Tarcoles bridge (Puntarenas, Costa Rica), we managed to photograph a few dragonflies. The first is a Square-spotted Dasher (Micrathyria ocellata). This species ranges from central Mexico well into northern South America. I am aware of no records from the United States.

This dragonfly has no common name. Our intrepid guide and soon to be author of the Dragonflies of Costa Rica, suggests the name Square-spotted Dasher. Note, however, that English or Spanish names for Costa Rican dragonflies and damselflies found outside the United States are not officially sanctioned by anyone.

Saturday, August 5, 2017

American Crocodile

Our second stop on 2 July during our Costa Rica dragonfly tour was one I shall not soon forget. The highway (Route 34) crosses the Rio Tarcoles. The bridge is two-laned, with heavy traffic. Sidewalks, basically only wide enough for one person, run on both sides of the bridge. Tourist activity abounds. To think that this experience was free of charge! We parked and walked across where we rejoined our bus. We wondered what attracts the crocodiles. Undoubtedly they are fed. Pedestrian fatalities? Dragonfly hunters who venture down the river banks? We were scolded by tourist police when we tried to search for dragonflies.

American Crocodiles have “catholic diets” (Scientific American Blogs). They are tolerant of salt water, which has allowed them to inhabit many areas of the Caribbean. They range from northern South America up both coasts of Central America and Mexico. They are also found in Florida. The bump on their slender snout in front of their eyes is distinctive. Modern crocodiles grow up to 4 meters in length. Old records exist of animals almost twice that long.

Friday, August 4, 2017

Brilliant Blue Skipper

Several of our companions on our Costa Rican dragonfly tour knew their butterflies. This butterfly is a Brilliant Blue Skipper, Paches loxus. I knew North American skippers tend to be black and brown and difficult to identify. We saw several species of azure skippers during our trip. Surprisingly the Brilliant Blue Skipper appears to have little Internet presence, aside from a few photographs and specimens. Thus, I can’t tell you much about it. Perhaps a butterfly expert would care to comment.

Thursday, August 3, 2017

Lineated Woodpecker

While we watched the grassquit of my previous post, Erika heard a woodpecker drumming. She spied the bird working in a distant, large tree. Lineated Woodpeckers are common from the Mexican lowlands south across much of northern South America. This large woodpecker inhabits both humid and moderately dry forests. It prefers open woodland near clearings and forest edges, and even big trees in pastures or gardens

Lineated Woodpeckers eat a wide variety of wood-boring arthropods. They also take fruits, seeds, ants and other arthropods. They feed at all levels of the forest, including on the ground. They may feed at one location for 15 minutes before flying long distances to new feeding areas. They tend to be wary (Handbook of Birds of the World).

Wednesday, August 2, 2017

Blue-black Grassquit

Blue-black Grassquits fed on the Calle Loro roadside weeds as we came out from our dragonfly creek. This photo is of a female. Their streaky flanks are good field marks. Central American males are black. Some controversy exists on just how to classify grassquits. I thought they are small sparrows. The Handbook of Birds of the World considers them to be tanagers.

Grassquits are common from Mexico south across much of South America. Blue-black grassquits are found in weedy fields and roadsides. They  eat seeds and a few insects or berries. The forage on the ground or from weed-tops. They often form large flocks.

Tuesday, August 1, 2017

Black-winged Dragonet

Back up from the creek, we found a Black-winged Dragonlet along the Calle Loro roadside. This species is an uncommon stray into the south-central United States. Its main range is from Mexico and Central America south to Colombia and Ecuador. Adult Black-winged Dragonlets aestivate during the dry season. With the rains, they move from forests to open ponds (Odonata Central).