Barro Colorado Island, a natural monument for wildlife pictures

About BCI

Barro Colorado Island (BCI) is located in the man-made Gatun Lake in the middle of the Panama Canal. The island was formed when the waters of the Chagres River were dammed to form the lake in 1913. When the waters rose, they covered a significant part of the existing rainforest, and the hilltops remained as islands in the middle of the lake. Today it will be considered an environmental catastrophe.

BCI has an area of 15.6 km2 (6.0 sq mi) and was set aside as a nature reserve on April 17, 1923 by the U.S. Government. Initially administered by the Panama Canal Company, since 1946 Barro Colorado Island has been administered by the Smithsonian Institution, together with five adjacent peninsulas, as the Barro Colorado Nature Monument (BCNM). The BCNM has an area of 54 km2 and it is among the most-studied areas of tropical forest in the world. The Smithsonian Tropical Research Institute (STRI) has a permanent research center on the island, dedicated to studying rainforest ecosystems. Because the Island's diverse ecosystem has been very little altered by humans, Barro Colorado has been studied for over eighty years within a great variety of biological disciplines. Hundreds of scientists conduct research projects on Barro Colorado Island every year.

Visiting Barro Colorado Island

Visitors are allowed on Barro Colorado Island through a visitors program regulated by STRI. To visit BCI, you must make a reservation in http://www.stri.si.edu/formularios/reservations/reservations.php. Tours include transportation to and from the island by boat from Gamboa, a guided hike, and lunch. Hikes through the island offer up the opportunity to spot several creatures, including monkeys, anteaters, coati, agouti, birds, amphibians and insects.

The cost of the visit is US$35 and a private guide costs additional US$90. I recommend taking the private guide if you are like me and want to have a tailor-made experience. My main target was to make macro photography which take a lot of time and patience, and being with a tourist group was going to drag me. 

The last time I visited BCI I was a teen so I didn´t know what to expect from this visit, I was told that large birds like tinamus and guans where not shy or fearful of humans due to the protection they had have for the last 100 years, while in other parts of the country they are heavily hunted. So I prepared my backpack with all the macro stuff (100mm and 180mm lenses, 1.4x, 1.5x and 2x extensions, monopod, brackets, flash and lights) but also packed a 200mm lens just in case I encountered  larger animals or birds.

The photos

 Below I split the pictures in reptiles, birds, mammals, and arthropods.

Reptiles

The Delicate Ameiva or Delicate Whiptail (Ameiva leptophrys), commonly called jungle-runner and locally known as borriguero. It is a species of whiptail lizard found in Costa Rica, Panama and Colombia. As other members of the Teiidae family, have large rectangular scales that form distinct transverse rows ventrally and generally small granular scales dorsally, they have large head scales and a forked, snake-like tongue. They all possess well-developed limbs. All are terrestrial and diurnal, and are primarily carnivorous or insectivorous, although some will include a small amount of plant matter in their diet. They all lay eggs.


The Yellow-headed Gecko or White-throated Gecko (Gonatodes albogularis) is a species of gecko found in warm parts of Central and South America.  The species are also identified by their round pupils and digits without extending lamellae. Male yellow-headed geckos have yellowish heads and blue-black bodies unlike the female which are uniform in color. They feed on insects and are mainly diurnal. A study in Panama found that they may lay eggs on a seasonal basis, laying more eggs during the rainy season.

This gecko was being stalked by a vine snake. After taking the pictures of the gecko, I noticed the snake well camouflaged, pretending to be a vine. Once she notice I was taking pictures of her and that the gecko retreated she started moving to another place, and then I made the picture below with the macro lens.


Commonly known as the Mexican Vine Snake or Brown Vine Snake (Oxybelis aeneus), and locally as bejuquilla, is a species of colubrid snake, occurring only in the Americas. It is found from southern Arizona in the United States, through Mexico, to northern South America and Trinidad and Tobago. This is an extremely slender snake that reaches up to 1.9 metres (6.2 ft) in length. Its color may vary from gray to brown with a yellow underside. It is mostly arboreal and diurnal, and is quite often mistaken for a vine. It is a mildly venomous rear-fanged snake, but it is not considered dangerous to humans. However, a bite can cause an itching sensation. It is oviparous.

The Dactyloidae are a family of lizards commonly known as anoles. Anoles' diets include insects and other invertebrates, with crickets, spiders, and moths being some of the most commonly consumed prey. Anoles are opportunistic feeders, and may attempt to eat any attractive meal that is small enough. These subtropical lizards are semiarboreal. They usually inhabit regions around 3–6 m (10–20 ft) high. Shrubs, bushes, and short trees are common hiding places. 43 species occur in Panama.

We also observed amphibians like Dendrobates auratus, and several other frogs and toads but I didn't get good pictures of them.

Birds

As stated above I left my "bird lense" (400mm f2.8) home, because I was going to focus on macro photography. However, I was wise enough to take my 200mm f2.8 with me, which with a 2x extender converts to a 400mm f5.6, good enough for large birds. We found a flock of Crested Guans (already introduced in this post: http://panama-wildlife.blogspot.com/2014/12/finca-ceriana-2.html). It was impressive that they were not really altered by our presence allowing me to make these great shots. Other birds observed were Great Kiskadee, Western Slaty Antshrike, a nesting pair of Slaty-tailed Trogon and Great Tinamu.

Mammals

I was making a macro shot when we heard a squirrel gnawing a Bactris' fruit. The pose and the moment was great. The boat was about to sail so I had no chance to switch lenses, so with the 180mm f3.5 macro plus a 2x extender, I was at 360mm f7.1, and had no autofocus. Great technique was required and I finally got a sequence of shots, being the one below the one I liked the most. This was the moment when the squirrel was retiring with the "nut" in its jaws.

The Red-tailed Squirrel (Sciurus granatensis) is a tree squirrel found in Colombia, Costa Rica, Ecuador, Panama, Trinidad and Tobago, and Venezuela.

Bactris is a genus of spiny palms (you can see some spines at the bottom left of the picture) which is native to Mexico, South and Central America and the Caribbean. Most species are small trees  but some are large trees while others are shrubs with subterranean stems. They have simple or pinnately compound leaves and yellow, orange, red or purple-black fruit. The fruit of several species is edible, most notably B. gasipaes (locally known as pixbae), while others are used medicinally or for construction. The pixbaes are very nutritious but need to be cooked for 3–5 hours, they are boiled in water with salt and little vegetable oil. Bactris' fruits also benefit many animals in the wild, like these squirrels that pick ripe fruits from the ground, gnaw the exterior layer (exocarp) and all the fibrous flesh (mesocarp), and then eat the inner layer (endocarp), which resembles a small peeled coconut, and contains the edible seed inside.

Other mammals we observed were Coatis and Howler Monkeys.

 

Arthropods

Emesinae, or Thread-legged Bugs, are a subfamily of the Reduviidae (assassin bugs). They are conspicuously different from the other reduviids by their very slender body form. They are stalking, predaceous insects. They walk on their mid and hind legs; the front pair is raptorial, used to catch prey. Very little is known about emesines, they are worldwide in distribution; however, they are most abundant in the tropics.

Ant carrying a drop of water.


Dictyopharidae, identified by the antennae arising on the side of the head below the compound eye and elongated frons.

Aztec Ants (Azteca sp), workers. They measure between 1 and 1.5 mm and build arboreal nests like the one shown below.

 Photo taken from the Internet


Golden Carpenter Ants (Camponotus sericeiventri) are 1/2 inch long ants that live in colonies in the tropical rainforests of Central and South America.  They dig their nests in the wood of dead trees or soft-wood living trees.  They use their strong serrated mandibles (jaws) to burrow into the wood, building tunnels and rooms for storing food and raising larva. One of the most fascinating things about golden carpenter ants is that they are farmers too, they look after "herds" of aphids to eat the sweet excretions the aphids leave behind when they eat leaves. However, their main food sources are collecting seeds, scavenging dead animals and hunting other insects.





Millipedes are arthropods in the class Diplopoda characterised by having two pairs of jointed legs on most body segments. Each double-legged segment is a result of two single segments fused together as one. Most millipedes have very elongated cylindrical or flattened bodies with more than 20 segments.


A very small caterpillar


Turtle Gliding Ant (Cephalotes atratus)
Cephalotes is a Neotropical genus of tree-dwelling ant species, commonly known as turtle ants. All appear to be gliding ants. Gliding ants are arboreal ants of several different genera that are able to control the direction of their descent when falling from a tree. Living in the rainforest canopy like many other gliders, gliding ants use their gliding to return to the trunk of the tree they live on should they fall or be knocked off a branch. Gliding was first discovered for Cephalotes atratus in the Peruvian rainforest.


Then I found this insect which I have never seen before. I told the guide this was not a dragonfly, it seemed so different than all the dragonflies I know, specially because of the long antennae and the eyes. He insisted it was a dragonfly (Odonata order) due to the elongated body. Finally, after some research done later at home, I was proven right.

It was an Owlfly, a dragonfly-like insect with large bulging eyes and strongly knobbed antennae. They are in the Neuroptera order in the family Ascalaphidae; they are only distantly related to the true flies (Diptera), and actually even more distant from the dragonflies and damselflies (Odonata). They are diurnal or crepuscular predators of other flying insects, and are typically 5 cm (2.0 in) long. Many owlflies even hold their wings spread at rest like dragonflies; perhaps this is a form of mimicry to benefit from the fact that dragonflies are aggressive predators which smaller predatory insects would be better to avoid.

Specifically a member of the Ascalaphinae subfamily that is found in the tropics. Their characteristic apomorphy is the ridge which divides each of their huge compound eyes; they are thus known as split-eyed owlflies.


The Micropezidae are a moderate-sized family of acalyptrate muscoid flies in the insect order Diptera, comprising about 500 species. They are most diverse in tropical and subtropical habitats, especially in the Neotropical Region. Insects in this family are commonly called stilt-legged flies, after their characteristically long legs. The fore legs are markedly smaller than the other pairs. Mostly they are long-bodied, often black flies, usually with infuscated (darkened) wings.


Synoeca is a genus of eusocial paper wasps found in the Americas. Commonly known as warrior wasps or drumming wasps, these insects are known for aggressive behavior, a threat display consisting of multiple insects guarding a nest beating their wings in a synchronized fashion, and an extremely painful sting. Synoeca is one of only three insect types (the others being the bullet ant and the tarantula hawk) to receive a rating of 4 or higher on insect sting pain indices such as the Schmidt sting pain index.


The large and diverse insect family Miridae contains the plant bugs, leaf bugs, and grass bugs. It is the largest family of true bugs belonging to the suborder Heteroptera, with over 10,000 known species and new ones constantly being described.

Conclusion

I went to BCI on a weekend day which cut me 2 hours of regular visitor hours that are offered during the week days, and honestly it was not enough time to do all I wanted. I would like to stay at least for two days. There is a lot of wildlife on every corner just waiting to be discovered by my lenses, I didn't find the place to be special for birds, although they proved to be very tolerant to human presence, the birds found there can be found in other places. The little human intervention in the island favors wildlife photography as much as favors scientific investigation. I'm glad I was not mistaken choosing my macro lenses for this adventure and I will repeat it any time. However, now I have another destination in my list, soon I'll go to another island, this time in the Pacific Ocean.