Archive for the ‘Philip Davison’ Tag

CUCKOO WASPS:  A DAZZLING PARASITE   2 comments


Wildlife, nature, fauna and flora of Costa Rica.

Now the weather has taken a significant change.  The rains that are expected to fall in September have started in earnest.  The rain is now falling all day and on most days.  This is good news for the frogs and this year the breeding continues on without a drop in intensity.  Every night there are large numbers of calling males.  The females are obviously responding because every morning there are lots of freshly spawned eggs.

After 17 years of data collection for my study, “Using amphibian and butterfly populations as a measure of environmental health”, I have decided to call it a day and now have to sit down and analyze the data.  Essentially I have been collecting data on population dynamics of butterflies and amphibians as well as recording daily weather conditions.  I look at changes in butterfly populations measured against temperature and amphibian populations measured against precipitation.  There are a great many other variables to be taken into consideration but watch this space for news of what the data might be showing us.

Butterflies in the Sun

Due to the constant rain and the trails running like streams, I have not been able to spend as much time outside as I would normally wish.  However, on the one day I did manage to get out and take some photographs I was rewarded with a mixed bag of goodies of which only one was new to me.

One morning the sun was shining and the butterflies were taking advantage of its warming rays.  The Lantana camara bushes are always a big nectar draw for the butterflies and this day proved to be no different.  Although there were nowhere near the number of species found during drier periods of the year there were enough to try and take a few shots.

One very small but distinctive butterfly that I have a particular liking for, (I don’t know why), is the Tropical Checkered Skipper, (Pyrgus oileus).  It is a fairly common skipper with a wide geographical distribution from southern North America and through into Costa Rica.  At a distance the black and white checkered pattern make it stand out against the green of the grass where it is normally found flying close to the ground.  When seen close up the wings and body are covered in a grey/blue fur.  The females tend to be a darker overall color.  The caterpillars feed on plants in the family: Malvaceae, of which there are several species growing in abundance locally.

Rainforests. Butterflies. Costa Rica. Veridion Adventures. Hesperiidae. Pyrginae. Pyrgus oileus.

Tropical Checkered Skipper, (Pyrgus oileus)

They belong in the family: Hesperiidae and the subfamily: Pyrginae or Spreadwing Skippers due to their habit of basking with the wings wide open.  There are approximately 50 species in the genus: Pyrgus and they can be found throughout Europe, Asia, North, Central and South America.  You are more likely to find Tropical Checkered Skippers in open sunny locations which is where I found this one.

Feeding on the nectar of the same patch of Lantana was yet another Spreadwing Skipper but one which looked completely different to the Checkered Skipper.  This was a Long-tailed Skipper, (Urbanus proteus), notable for the two long tail-like extensions of the hind wings.  There are several species of Long-tailed Skippers in the immediate area but each one has distinctive markings to the wings.  The dorsal surface of the abdomen and the wings are covered in metallic green hairs.  Again it is a widespread species ranging from southern North America, down through Central America and into South America.  The larvae feed on leguminous vines of which there are many species growing locally.  In North America it is sometimes considered a pest as it feeds on commercially grown beans.

Rainforests. Butterflies. Costa Rica. Veridion Adventures. Hesperiidae. Pyrginae. Urbanus proteus

Long-tailed Skipper, (Urbanus proteus)

This individual can be seen using its proboscis to probe for and suck nectar from the Lantana blooms.  One of the changes I have documented over the past 17 years is the progressive increase in annual average temperatures. One of the impacts this may have on butterfly populations is with increasing temperatures there will be increasing evaporation of the nectar.  This in turn causes an exponential increase in nectar viscosity.  We could end up with a situation whereby if the temperature increases to the point where the nectar is too viscous for the butterflies to suck up, then they may well not be able to feed, bringing about starvation, death and a collapse in butterfly numbers.  This is one of many variables I have to take into consideration when looking at the fact that we have had a 35% decline in butterfly species over the past 17 years.

Cuckoo Wasps: A Dazzling Parasite

While watching the butterflies flit back and forth, only stopping momentarily to take a feed of nectar, I noticed a tiny metallic green insect, only about 10mm long.  It was on top of a leaf at eye level and not moving.  It was striking in that the green was very reflective, it looked like a piece of metallic foil.  I was looking at a Cuckoo Wasp.  I have only ever photographed one in the past so if this one did not move then here was a second opportunity beckoning.  I slowly lifted the camera and got the shot but as I moved my position for a head on photo it took to the air and disappeared.

Cuckoo wasps are solitary wasps of the order: Hymenoptera, which includes bees, wasps and ants amongst others.  They belong in the family: Chrysididae, after the Greek word Chrysis – golden vessel.  They are also known as Jewel Wasps and they certainly have a jewel-like quality to them.  The refraction of light produces the spectacular metallic coloration, similar to the iridescent blues of the Blue Morpho butterflies.  In this case it is the multi-layered waxy cuticle of the wasp’s exoskeleton that produces the refraction.  There are about 3,000 named species of Cuckoo Wasps and they are found in most parts of the planet.

Rainforest insects. Hymenoptera. Chrysididae. Cuckoo Wasp.

Dazzling parasite, Cuckoo Wasp, (Chrysididae sp)

The name Cuckoo Wasp refers to the fact that, depending on species, they are either parasitoids or kleptoparasites preying upon other wasps.  Like any parasite dealing with a dangerous host it has to have evolved behavioral methods that allow it to get in and get out without being discovered or be killed.  To that end it has a very sneaky strategy.

A female Cuckoo Wasp will case the joint she is about to infiltrate.  She watches and waits for a female Digger Wasp to begin making a burrow.  When the Digger Wasp starts to bring in paralyzed prey on which to lay her eggs, the Cuckoo Wasp either hangs onto the immobilized victim and will be dragged into the burrow, or she waits until the Digger Wasp has left on another foraging trip and she will stealthily slip into the burrow.  If caught in the act, all is not lost.  Some species of Cuckoo Wasp have a concave underside and can roll into a ball.  The sting of the enraged host will not penetrate the heavily pitted exoskeleton of this now globe-like emerald.  The host has to physically carry the Cuckoo in the nest out in its jaws where it will then sit and watch till it can strike again.

Having subverted the hosts defenses, the female Cuckoo Wasp lays its eggs.  Some species are kleptoparasites, once the egg hatches and the larva emerges it will kill and eat the host larva and then consumes the food the host female is providing for it.  It remains undetected by mimicking the chemical signature odor of the host.  Others wait for the host larva to grow and then kill and consume it before it pupates.  Then like its avian namesake, it is the Cuckoo that thrives within the nest of its unwitting host and eventually emerges as a new parasite.  They parasitize a wide variety of hosts from solitary wasps and bees, to sawflies and walking sticks.  Unlike many other wasps where the ovipositor is modified into a lethal sting, the Cuckoo Wasp has a modified ovipositor and reduced venom sac so has no potentially lethal means of attack or defense.

Who would of thought as I photographed this gorgeous glowing emerald insect that it would have such an insidious life history.

A Collection of Queens

Another wasp nest that I have been walking past over the past month or so has been not only gradually increasing in size but is now populated by more adult wasps tending it.  It is the nest of one of the Social Paper Wasps, (Polistes sp).  The original queen had created a few cells beneath a leaf in each of which she laid an egg.  The eggs hatched, the larvae she provided with a food of chewed up insects until they were large enough.  She then capped the cell of the now pupa and waited for it to emerge.  The new wasp is one of the original queen’s offspring and like their mother they are equally capable of mating and reproducing.

Rainforest insects. Paper Wasps. Hymenoptera. Vesperidae. Polistinae. Costa Rica. Veridion Adventures.

Female Paper Wasp, (Polistes sp), guarding her nest.

To begin with they help with the nest, building more cells, tending the larval siblings, foraging for food and helping the nest to increase in size.  The cells are constructed from masticated vegetative material.  Prey is caught and chewed up for the larvae to feed.  The sting is only used defensively.  They will attack any potential predator that approaches too close.  So, my approach was one of great stealth.  I took a few took a few exposures but the flash was beginning to antagonize them and one took flight and started buzzing around my head which was my cue to slowly back off and leave them to their business.

The other females usually have reduced ovarian systems but dominance of the original queen is not always assured.  Fights break out and a new queen can become established within the hierarchy taking over the major reproductive role.  When the male wasps emerge, they may stay on the nest for some time before leaving.

Philip Davison Is a Biologist, Writer and Photographer Based in Costa Rica

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BEETLES: HIDING IN CLEAR VIEW   6 comments


Wildlife, nature, fauna and flora of Costa Rica.

It has been another week of sunny days and rainy nights.  Last month the immediate area experienced almost 28 inches, (706 mm), of rain.  That is approximately 1 inch per day.  However, as to be expected, the pattern of precipitation was not that evenly spread.  There were several nights with really heavy downpours which accounted for a third of the total.  There were more nights when it rained hard but not in a deluge and then there were nights when there was no rain.

Atop Cabo Matapalo, at 500 feet, (150 m), above sea level, there is little chance of flooding, all the water is runoff.  This time of year the ground is saturated so when there is a torrential downpour the water may remain on the surface forming large areas of standing water which quickly drains away.  The creek water level is high and rushes down the channels, falling over rapids, cascades and waterfalls and finally flowing into the sea.  After a night of very heavy rainfall, the creek will have turned murky brown with the volume of sediment it is carrying.  Given a few days of sun the water will have returned to its crystal-clear state, inviting you to plunge into its cooling depths as a relief from the hot and humid atmosphere of the forest.

A Typical Rainy Season Day In The Forest

You wake in the morning, opening your eyes but still not fully conscious.  You had a good night’s sleep, restful and undisturbed, but were brought out of your slumber by a distant roaring sound.  It is still dark outside so what time is it?  Early, pre-dawn, and the roar is heard again, this time joined seconds later by a response, louder roaring but much closer to your cabin.  All of a sudden the roars are echoing around the forest.  To many, the first-time visitors to a Central American rainforest, this could only be large ferocious beasts gathering to collectively do you harm.  To the more savvy, seasoned visitor this is a familiar wake-up alarm call, Howler Monkeys, announcing their location to one another so that different troops can keep their distance during the course of the day.

It did its job as far as you are concerned, you are now fully awake.  The first light of dawn starts to brighten the sky, throwing the form of the trees into dark silhouettes.  Here you are only 8⁰ north of the equator so the dawn twilight does not last for long.  The sun rises rapidly and the grey sky turns blue.  The birds are awake now.  Flying overhead are noisy macaws and parrots heading off from their roosts to the feeding grounds.  Their squawking and screeching is not the most melodious of avian calls.  From within the forest the Chestnut-backed Antbird, Black-hooded Antshrike and the Bright-rumped Atilla are some of the first choristers to greet the new day.   The males are vocally drawing up the bounds of their territories.

It is after breakfast and the sun is now high in the azure sky.  The temperatures have rapidly risen from the cool chill from when you opened your eyes.  The air is still.  You grab your camera and head off into the shade of the forest.  The only sound is that of cicadas, their loud calls increasing in intensity, volume and pitch as the morning progresses.  Here and there from different points in the unseen depths of the forest, obscured from your vision by the trunks of the trees are more birds calling.  The familiar “Who cooks for you” of the Short-billed pigeon, the high-pitched squeaky call of the Black-mandibled Toucan, it sounds more like a rusty pulley that needs oiling than the call of a bird.

You see many things close at hand to photograph, flowers, fruit, a beetle, a praying mantis, small frogs and lizards.  Up above you the Spider Monkeys put on an impressive display of acrobatics as they swing through the tree tops.  You can’t miss Spider Monkeys with their high-pitched chattering and high-energy crashing through the tree tops.  This is in complete contrast to the languid slow moving and deeply voiced Howler Monkeys.  You come across a troop of White-faced Monkeys, more leisurely in their pursuit of a meal.  You see them peeling away bark and turning leaves, always gleaning, looking for the small creatures that make up the bulk of their diet.

It is approaching midday.  The sun is directly overhead.  Despite being beneath the shade of the canopy, the temperatures have risen dramatically.  Combined with the high humidity, conditions have become like those in a well stoked sauna.  If the air was still outside the forest, within its confines there is not a breath of air.  The sweat is rolling down your face and your clothes are now soaked.  Thankfully you brought a lot of water with you and a packed lunch.  Time to take a break for some respite in order to recover you waning energy levels.

As you sit, taking in the sounds around you, a rumbling can be heard off in the distance, thunder.  You finish your sandwiches, take a swig of water, pack everything into your bag and head off down the trail once more.  You stop to photograph a line of Leaf-cutter Ants.  You need to get close to the ground and have some patience to capture the individual caste members.  You are rewarded a little later with a swarm of Army Ants, incessant in their drive forward flushing out non-flying arthropods.  They are accompanied by a mixed flock of ant-birds, woodpeckers, woodcreepers and Grey-headed Tanagers, all in a heightened state of excitement as they feed on the flying insects driven out of hiding by the Army Ant assassins.  Lots of photographic opportunities here.

It is now much later; the almost unbearable temperatures have dropped and the sun is sinking fast towards the western horizon.  Also, that rumbling is getting louder and the sky is rapidly darkening in the east.  You have filled your memory card with images so it may be astute to pick up the pace now and head back to base.  Before too long a breeze picks up and the tree crowns begin to sway.  Loose leaves and small twigs come tumbling down from the canopy.  It is rapidly darkening and the breeze becomes a wind.  The trees are now swaying more violently and you can hear branches being snapped and crashing down.  All of the monkeys start to shriek in objection to their homes being shaken in this manner.  The advancing storm has no ears and cares not for their protestations. Light rain begins to fall.

Within a shorter time than you would have liked, the sky above you has turned black.  The rumbling thunder has become loud and explosive, now accompanied by almost instantaneous flashes of lightning.  The rain comes out of the heavens with an ever-increasing intensity.  The canopy is being lashed.  Leaves and branches are torn from the trees by the sheer weight and force of the water being poured upon them.  Lightning is cracking and fissing around you, the storm is immediately overhead, these are thunderflashes and this is not a safe place to be.  The path at your feet which moments earlier was soft and damp is now a running river albeit only a couple of inches in depth.  The question is should you stop and find shelter or should you persevere on.  You chose the latter option.

Your step quickens, not too fast as you don’t want to slip and fall.  You hear a sharp crack above you, then a loud snap and a huge branch comes tumbling with force through the understory.  It hits the ground so hard that it stands upright as if it had been planted.  The flashes are lighting up the whole sky in a blinding white light.  Each boom of thunder causes you to flinch.  It is raining so heavily that you can barely open your eyes due to the stinging pain it causes you.  But you are almost there, the path out of the forest is up some stairs and around a bend on the trail.  The steps are now a series of cascades but the tumbling water does not hinder your stride.  You will soon be back in the dry comfort of your cabin.

Just as you step out of the forest and into the open garden area, the driving rain suddenly subsides to that of a light summer shower.  The black sky starts to lighten and the deep rumbles roll off into the distance.  Each flicker of lightning is still causing flashes but now over on the horizon.  Thankfully you had the foresight to pack all of your equipment into a waterproof camera bag before the deluge descended and it seems to have served its purpose well.  The rain becomes drizzle and finally peters out then stops.  The sky is now pale grey and the sun sinks to the point where the final rays light up the underside of the clouds in a deep orange.  You have just experienced a typical September day in a Costa Rican rainforest.

Beetles Hiding In Clear View

Beetles, there are thousands of species and yet if you go out with the intention of finding them you may become aware very quickly that they are not as obvious as you have thought.  Turning over rocks or peeling rotten bark from fallen trees may produce one or two species but nothing in profusion.  That is why when I head off into the forest it is never with the purpose of photographing anything specific, not unless I have seen something that I wanted to return to.  Some people go out having birds or mammals as their goal, I am always looking for smaller things, as regular readers of the blog will already know.  The camera will have my favorite 105mm macro lens attached and will be set to take photos of all manner of mini beasts in darker conditions.  The shots will be hand held as I only take the tripod if I have a certain subject in mind.

Last week I found two different species of beetle out in the open aspect of a sunny forest edge.  They were in separate locations but within the same area.  They were both sitting on top of a leaf, in bright sunshine and would not stay still.  I had to keep maneuvering around the subject to try and get a decent image.  Every time I had things set, they would turn their backs to me and wander off along the opposite length of the leaf.  Finally, after much repositioning, I managed to obtain some acceptable photographs.  One of the problems with photographing beetles is the hard, smooth and glossy exoskeleton that many of them have.  It reflects the light from the flash gun.  To obtain the depth of field that I prefer, with a moving subject I have to use very small apertures and by necessity I need to add extra light with flash.

The first beetle is a Pleasing Fungus Beetle, (Cypherotylus asperus), in the family: Erotylidae.  I am not sure why they are pleasing but fungus beetle refers to their main dietary item which may come as no surprise, fungus.  The bright red blotches against a black background is aposematic, or warning coloration.  If molested or attacked, the Pleasing Fungus Beetle emits a foul-smelling odor that would cause most would be predators to back off.

Rainforest animals. Rainforest insects. Rainforest Beetles. Coleoptera. Erotylidae. Cypherotylus asperus.

Pleasing Fungus Beetle, (Cypherotylus asperus)

The second beetle is a Leaf Beetle in the family: Chrysomelidae.  They typically have the domed body, clubbed antennae and are multi-colored.  But as there are almost 50,000 species in this family I have, so far, been stumped as to which species this is.  Should any beetle expert be reading this and would like to provide a name I would be most grateful.  The clue to the diet is once more in the name.  They feed on the leaves of a variety of vegetation.

Rainforest animals. Rainforest Insects. Beetles. Coleoptera. Chrysomelidae.

Leaf Beetle, (Chrysomelidae sp)

The Earth Moved

Walking through the forest you can often have your attention momentarily attracted by some small movement down in the leaf litter.  It may be ants, spiders, lizards, frogs or a myriad of other small creatures that live concealed beneath the carpet of rotting leaves.  It is the tread of your footfall that will disturb them and have them run for cover out of harm’s way.  Depending on the speed of the animal you may lose sight of it very quickly.  Some move from leaf to leaf.  Generally if any of these litter living denizens gets below the leaves it will be gone and unless you are lucky you will just have to imagine what you saw.  Occasionally though one will freeze when exposed to the light.  Last week, my size 13 boot thudding into the ground caused a tiny frog to jump out of the imminent descending disaster.

There are several small frogs that inhabit the dark and damp environment of the forest floor.  The squat body shape of this one revealed its identity almost immediately.  It was one of the rather delightfully named dirt frogs, this one being a Stejneger’s Dirt Frog, (Craugastor stejnegerianus).

Rainforest animals. Rainforest amphibians. Frogs. Anura. Craugastoridae. Craugastor stejnegerianus.

A tiny Stejneger’s Dirt Frog, (Craugastor stejnegerianus)

The dirt frogs are totally terrestrial frogs, they live their whole life on the forest floor and never need to go to water as many amphibians do.  They still have moist skins through which they largely breath and therefore by necessity can’t leave the confines of the damp environment under the trees.   There are several species that live in this area and Stejneger’s Dirt Frog is one of the commonest.

They belong to the family: Craugastoridae or the Fleshbelly Frogs.  Typical of this family is the reproductive habit of direct development which negates the necessity of them having to return to water to reproduce.  The frogs pair up, (I can’t say I have ever heard these frogs calling), and the female lays her eggs amongst the leaf litter on the forest floor.  There are only about 20 – 30 eggs but they are fairly large in comparison to the adults.  The egg is packed with yolk and the tadpole develops within the egg, there is no free-swimming tadpole stage.  After about 8 weeks a tiny copy of the adult emerges.

Rainforest animals. Rainforest amphibians. Rainforest Frogs. Anura. Craugastoridae. Craugastor stejnegerianus. Osa Peninsula. Costa Rica.

Dorsal view of Stejneger’s Dirt Frog, (Craugastor stejnegerianus)

As you are walking through the forest, if you keep your gaze lowered scanning the ground then you will surely see a small piece of the earth move.  Given closer inspection then you will probably find you are looking at a dirt frog.  But take a photograph as they are not always easy to identify.

Fying Dragons.

A few weeks ago I managed to photograph a dragonfly with black bases to the wings, a Black-winged Dragonlet, (Erythrodiplax funerea).  This week I managed to capture another dragonfly but with the inverse situation of having black tips to the wings, the Large Woodskimmer, (Uracis fastigiata).  This one was found in a different area to the previously mentioned species but they had been there for several weeks.  This species was found in secondary forest, in a light gap and always close to the ground.  Once again my attempts to take a picture were always doomed to failure because every time I lifted the camera to my eye, they would fly off.  But as we know with photography patience is a virtue and finally after several weeks I got lucky.  This one stayed still long enough for me to get several pictures.

Rainforest animals. Rainforest Insects. Dragonflies. Odonata. Libellulidae. Uracis fastigiata

Large Woodskimmer, (Uracis fatigiata)

Unlike the dragonflies which can be found in open sunny locations around a body of water that have fast flight and hover, these forest species seem to be more sedentary and perch on low vegetation and only seem to move if disturbed.  Having excellent eyesight adapted to detect movement it does not take much to disturb them.  It could be that they are sit and wait predators just diligently watching for the right sized meal to pass by before taking off to capture it.

Philip Davison Is a Biologist, Writer and Photographer Based in Costa Rica

An Orgy of Green Pain   6 comments


Philip Davison Nature Diaries. Bosque del Cabo Rain Forest Lodge.

Parachuting into an Orgy

The past week has been a mixture of sun and rain.  The days have been gloomy with heavy, brooding overcast skies.  Occasionally the clouds part and the sun has shone down to light up the shadows.  But the menacing grey blanket that covering the area from north to south and east to west always threatened to unleash a downpour.  Sometimes the drizzle filled the air from dawn to dusk but you knew there was more to come.  By late afternoon the light rain would turn to heavy and by the time the sun had set below the horizon then the heavens would open drenching one and all.

The amphibians have been enjoying the onset of the rainy season, their numbers increasing over the last month but these more persistent nightly deluges have had the frogs collecting in huge numbers and rejoicing in a reproductive frenzy.  One frog that responds to torrential rain is the Parachuting Red-eyed Green Tree Frog, (Agalychnis spurrelli).

Agalychnis spurrelli. Hylidae. Pseudomedusinae.

Parachuting Red-eyed Green Tree Frog, (Agalychnis spurrelli)

One evening, just after sunset it started to rain heavily and by next morning we had experienced 11 inches of rain.  That was the trigger that stimulated hundreds of Parachuting Red-eyed Green Tree Frogs to leave the canopy, which is where they reside out of view, and launch themselves into the air.  This frog has a uniformly colored dark mossy green upper side.  Its flanks are a pale lemon yellow.  It has large heavily webbed hands and feet of the same buttery hue and, of course, it has the large red eyes.  As they leap out of the canopy they spread the fingers and toes so the webbing is stretched tight, quite literally into a parachute of living tissue, which allows the frogs to glide down to the vegetation surrounding the pond without ill effect.

Each male quickly establishes a territorial perch from which he begins to call in an attempt to entice an egg-laden female his way.  The call is a short, soft, almost electronically-sounding sound.  Selecting a male on the quality of his call, the deeper the sound the better, the female makes her way over to the chosen chorister, he jumps on her back and they set off to visit the pond.  The female absorbs water through her skin and fills her bladder.  Now the female, not only with a body full of eggs but also carrying the male on her back, makes her way to a deposition site.  She chooses a broad leaf overhanging the surface of the pond and she commences to lay a sheet of eggs across the leaf.  At the same time as she releases the eggs from her body the male fertilizes them.  This normally take place just before daylight.

Parachuting Red-eyed Green Tree Frog. Osa Peninsula. Costa Rica. Philip Davison.

Parachuting Red-eyed Green Tree Frog Eggs.

As dawn breaks and the sun rises, the frogs have to get out of the light and into the dark as quickly as possible.  They don’t have time to get back to the canopy, parachuting down was a quick descent but the ascent involves a 100 foot climb and there is little time.  The sun continues to steadfastly climb in the sky.  Hundreds of frogs are now scrambling desperately to escape the skin-drying effects of its harsh rays.  This was the point at which I arrived, just in time to see countless small green goblinesque figures running along branches in a desperate effort to find a not already fully accommodated shelter.  I was not the only one.  A Bare-throated Tiger Heron had found itself an early morning breakfast bonanza and was picking off the unfortunate amphibians one after the other.

The larvae will develop in the eggs for about 7 or 8 days before the gelatinous mass liquidizes and the wiggling tadpoles drop into the pond water.  There they will complete the tadpole stage and if they make it through the aquatic stage will finally emerge after 7 or 8 weeks as a tiny froglet which will eventually have to make its way to the tree tops.  The Parachuting Red-eyed Green Tree Frog is an explosive breeder and these episodes can only be witnessed following those biblical-like rain storms.

Agalychnis spurrelli. Bosque del Cabo.

Parachuting Red-eyed Green Tree Frogs After Sunrise

Showing Off in the Green Room

The forest flora can be flamboyant and gaudy or subtle and subdued.  The blooms may appear abruptly in a visual feast or occur in small numbers isolated and hidden in the dark green depths the subcanopy.  Some plants flower but once a year, a spectacular show drawing the eye like a beacon which is setting the tree tops ablaze and illuminating the forest canopy in a patchwork of color on natures silvian canvas.  It is no wonder that the largest percentage of insect life resides and thrives at the tree tops.  Here you will find a kaleidoscope of dancing butterflies waltzing from bloom to bloom in search of the energy rich nectar, so vital in allowing these ephemeral beauties to complete the final stage of their short adult lives.  Other plants may flower continuously throughout the year but only producing one or two blooms at a time.

It is not just the butterflies that rely upon the flowers.  Many other insects are attracted by their rich colors and evocative scents.  The plants will sometimes target birds or mammals to do their bidding.  The plants offer the animals rewards but there is method to their bribery.  These are windless forests; a zephyr is the strongest a current of air that will move through the trees.  Pollen needs to be transported from one plant to another in order for the plants to reproduce.  It helps if the plant can target and reward a specific agent to enable its pollen to be deposited in the flower of the same species.

The plants cannot rely on wind for seed dispersal either.  Once more they have evolved the means by which to encourage animals into becoming innocent vectors of transfer and movement of the seeds that will potentially give rise to the next generation.

Over the last week as I was walking along the paths through the forest I could see some of those secretive flowers blooming in the shadows as well as some bright vivid forms, their colorful flower heads breaking up the somber borders of the trails.  One of the more subtle blooms was that of the Spiral Ginger,  (Costus scaber).  The flowering head is a rather stout, deep red spike composed of bracts, each of which will produce a bloom.

Costus scaber. Costaceae. Osa Peninsula. Costa Rica.

Spiral Ginger, (Costus scaber)

The fiery orange, yellow-tipped flower sticking out of the bract attracts in hummingbirds which are the principal pollinator of this species.  The colors red, orange and yellow are commonly used by plants to attract hummingbirds, these being the colors in the spectrum that are complementary to the background green of the leaves.  These are also very hot colors whereas green is a cool color and so they readily stand out, particularly to animals that have keen color vision such as birds.  The hummingbirds hover in front of the flowers and probe within searching for the nectaries.  As they do so, the head and bill pick up pollen from the anthers which is transferred to the stigma of the next flower it visits thereby effectively pollinating the plant.

The family Costaceae is closely related to the ginger family: Zingerberaceae.  Most gingers are Asian but there are some gingers native to the Neotropics.  Most costas are American but there are some costas that are native to Asia.  There are 23 species of costa native to Costa Rica, 14 of which are found on the Osa Peninsula.  As they all look similar it is not too hard to identify them as costas but it is a little more difficult to identify them to species level.

Queen of Pain

Insects are fascinating creatures to photograph.  Once you have downloaded the image and zoom in, as long as the picture is in sharp focus, then the body form and colors become compelling.  All of the joints, the body plates and the detail of the head and wings will keep the naturalist mesmerized.  You can conjecture as to the function of all those different hairs and how the body parts articulate.  Not only that but how does the creature live, what is life history and what are the multitudinous, complex interconnected threads that tie it into the ecosystem of its habitat.  Insects complete their lives in almost as many ways as there are species.  Many insect’s lives are a mystery to us, we simply have no idea how they get from egg to adult.  That is not surprising as there are more species of insect on the planet than any other group of animals.  Because we don’t know, then that makes us more eager to study and discover more information to unravel those mysteries.

One groups of animals, the Hymenoptera, bees, wasps and ants, provide an endless source of material for research.  Many of them have well documented life histories and they work to a general pattern but there are variations.  I saw this wasp guarding its brood in a nest under a leaf in the tropical garden.

Although the wasp appeared to be alone, it was one of the social wasps belonging to the family: Vespidae.  The nest is made of carton which is a chewed up fibrous vegetable material, quite often wood, which forms the cells into which the eggs are laid.  The egg hatches and the larva develops, growing rapidly on a diet of chewed up insect prey captured by the queen.  The queen only uses her sting for defense, the prey is caught and chewed-up in the mandibles.  A pale larva lacking in pigment, can be seen in one of the cells.   When the larva pupates, the entrance of the cell is capped by a carton lid from which a new adult will emerge sometime later.

Polistinae sp. Hymenoptera. Vesperidae. Polistinae.

Paper Wasp Queen on Nest, (Polistinae sp)

There were, in fact, two wasps sitting on the nest.  This suggests that they belong to the subfamily: Polistinae.  These colonies consist of one or two queens both of which are responsible for the construction of the nest and raising the offspring without the aid of other workers.

Even if nobody told you, then you would learn very quickly from painful experience to leave wasps alone.  The black and yellow coloration of bees, wasps and hornets is the most visible of all color combinations.  As I have already mentioned, the wasp does not use its sting to subdue prey but rather uses it to defend itself.  But, as in many cases, it is better to use a deterrent rather than become involved in a physical battle where even though you may win, the probability is that you will sustain some damage yourself.  To ward off any potential threat, the wasps use threatening coloration.  It does not take too many painful encounters before most creatures would learn to avoid anything sporting that vividly distinctive black and yellow.

Philip Davison Is a Biologist, Writer and Photographer Based in Costa Rica

The Savage Death of a Velvet Cat   2 comments


Philip Davison Nature Diaries. Bosque del Cabo Rain Forest Lodge.

Sunny Days are Back Again

The weather has most certainly turned a corner.  After the record-breaking deluge that occurred continually over the course of the last five weeks we now have the opposite situation, no rain.  Not a single drop of rain has fallen over the past week.  The skies have been clear and bright blue.  The sun has been shining brightly.  The temperatures are on the rise.  The night skies have been clear and filled with stars.  Just within the space of seven days, the formerly soft muddy trails have started to harden up.  There are, of course areas where the ground is stiff soft and in places water continues to run off but these are now few and far between.  One trail had a new lake form as the water was unable to run off.  Walking along a familiar path I was finding myself waist deep in water.  I imagined that this new water feature may persist for months before the ground was exposed once more.  I was wrong.  Walking the trail a few days ago, all the water had gone.  The path was very muddy but no longer submerged.

Bosque del Cabo Rain Forest Lodge. Osa Peninsula. Costa Rica.

Zapatero Trail at Bosque del Cabo Rain Forest Lodge.

It was fortunate that the heavy rain stopped as the flowering season for many of the trees commences in December.  Should the trees bloom and then become bombarded with persistent downpours, the flowers can be knocked from the trees before they have been pollinated.  The result of this is a lack of fruit later in the dry season as the plants have not set seed.  There are many animals whose lives depend on the bounteous supply of mixed fruits that comprise their diet that should the flowering and fruiting seasons fail then they simply starve to death.  This happened in 2005 when substantial numbers of Spider Monkeys and Toucans were, quite literally, just dropping out of the trees.  Necropsies carried out by veterinarians showed that they were suffering from very low body fat.  They were starving to death.  Everything looks good at the moment for a bumper harvest as I have seen many trees starting to produce blooms.

Golfo Dulce. Cabo Matapalo. Osa Peninsula. Costa Rica.

The Sun is Shining Over the Golfo Dulce Once More.

Caught in the Eye of a Cat

The frogs are still out in numbers but those numbers will start to dwindle as we head into the dry season.  There are creatures that feed on frogs and they too have been out and about at night, the snakes.  One of the commoner snakes around the pond after sunset is the Cat-eyed Snake, (Leptodeira septentrionalis).  It feeds on frogs at all stages of their life history.  More particularly it searches out clumps of Red-eyed Green Tree Frog eggs which it finds suspended beneath the leaves overhanging the water.  The gelatinous masses are stuck in position and when the tadpoles reach about 7 or 8 days in age, the jelly liquidizes allowing the tadpoles to drop into the water where they complete the initial stage of their life history before emerging as froglets.  Frogs eggs make a perfect meal for the snake, they don’t run away or fight back and are packed with protein.  At the height of the amphibian breeding season, May, June and July, there are so many egg masses that the snakes start to look well fed and bloated.  Now, because there is little amphibian reproduction taking place, the snakes also fish for the tadpoles from beneath the water surface, take froglets as the emerge from the water and if they get the opportunity they will eat the adults too.

Red-eyed Green Tree Frog.

Red-eyed Green Tree Frog, (Agalychnis callidryas)

Agalychnis callidryas eggs

Red-eyed Green Tree Frog Eggs

Cat-eyed Snake

Cat-eyed Snake, (Leptodeira septentrionalis)

Leptodeira septentrionalis

Cat-eyed Snake. Close up.

The Fatal Velvet Kiss

Whereas the Cat-eyed Snakes feed on the smaller frogs, there is a much larger snake which feeds on the larger frogs.  One of the largest frogs in Costa Rica is the Savage’s Thin-fingered Frog, (Leptodactylus savagei).  A huge amphibian might make a satisfying for meal for any number of creatures.  To lower the risk of being predated upon Savage’s Thin-fingered Frog has several defenses.  It has a toxic skin secretion that can cause intense irritation of mucus membranes.  Should this prove ineffective it has a secondary defensive measure.  When it is caught, it issues a loud cry not dissimilar to a crying baby.  More importantly the call resembles the distress call of young caiman.  If there any adult female caiman in the area they charge in to defend their young, which means hopefully as far as the frog is concerned, it can then make its escape as its attacker is attacked.

Savage's Thin-fingered Frog

Savage’s Thin-fingered Frog, (Leptodactylus savagei)

But there are predators from which there is generally no escape.  It is not uncommon to see by the pond at night some substantially large sized Terciopelos, (Bothrops asper).  They are large pit-vipers in the same subfamily as rattlesnakes.  Like rattlesnakes they have a venomous bite that spells certain death for any prey victim it strikes.  An adult female can reach up to 6 feet, (2 meters), in length.  A snake that size demands a big meal and the Savage’s Thin-fingered Frog fits the bill.

Once the sun sets out come the Terciopelos.  They place themselves around the pond where an encounter with a frog is likely.  They are ambush predators; the cryptic coloration of muted browns and greys camouflage them perfectly against the background.  They remain motionless, camouflage works best if it is still.  Frogs, being mostly nocturnal, have large light gathering eyes.  They rely on movement to find food which is usually anything smaller than themselves, particularly arthropods, but sometimes smaller frogs too.  But the only movement they will detect from a hungry coiled Terciopelo will be one that is over in a flash.

Terciopelo. Crotalinae.

Terciopelo, (Bothrops asper)

The pit-viper is not so visually acute especially at night although its eyes will detect close movement.  Once the feeding response has been stimulated then the tongue comes into play, slowly flicking out then in again, each time tasting the air.  The tongue can detect parts per million of scent particles in the air and because it is forked it can pick up the gradient of a scent plume.  You and I may not know what a frog smells like but the snake does.  Then there are the pits that give it the sinister name pit viper.  These lie one on either side of the head between the eye and the nostril.  They are lined with cells that detect minute differences in background infra-red radiation.  They work best at responding to the presence of warm blooded prey such as rodents but their efficiency could also differentiate the small difference in body heat of even a cold-blooded creature such as a frog against the background temperature.

The unsuspecting frog passes by.  The snake has already drawn its head and neck into tightly sprung S-shaped.  The strike happened so fast that it would probably have been unaware, there would have been no time to react, no chance of escape.  As the snake’s head shoots forward and the jaws open, two long hinged fangs that lie flat against the upper part of the mouth now swing down.  They are simply two hypodermic syringes attached to glands that contain virulent life-ending cytotoxic venom.  The fangs puncture the skin like two needles, the force of the bite pushes them deep into internal tissues and organs.  The snake quickly recoils to avoid any retaliatory action by the victim in its final moments, not that a frog could inflict any damage but the bite of a rodent might.  The quantity of venom injected will spell doom and instant death for the unfortunate amphibian.  It probably would not feel anything from this lethal injection, the effects of which would most certainly be instantaneous.

The frog takes one or two steps forward then collapses dead in its tracks.  The snake is in no hurry.  The meal is ready whenever it would care to dine.  Lying patiently in the shadows the Terciopelo begins to smell the air with its tongue once more.  Once it is feels secure in the demise of its victim it slips forward, the tongue constantly flicking in and out over the cadaver.  It is searching for the head.  Snakes have no way of rendering a meal into small pieces and must swallow the prey whole.  Savage’s Thin-fingered Frog is a giant among amphibians, its body larger than the snakes head.  To deal with this inconvenience the snakes lower jaw disengages at the midpoint as do the upper and lower jaws where they hinge together at the side of the head.  Now the snakes gape can accommodate the huge frog body.  The snakes skin is highly elastic allowing it to stretch as it moves forward over the meal and with continuous backward moving S-shaped waves the feast is delivered finally to the stomach.  The snake moves away back into the shadow of the undergrowth where it will lie motionless for some time until it has digested the hearty dinner.

Terciopelo. Leptodactylus savagei

Terciopelo eating a Savage’s Thin-fingered Frog

Payback Time

There are times when even the top predators can become prey.  Where there are snakes then there might be snakes that eat snakes.  Sure enough on occasion by the pond where the Terciopelos lie in wait there is a hunter that actively seeks them out.  A hunter that is immune to the deadly venom.  A hunter that can overpower with impunity its adversary.  That hunter is the Mussurana, (Clelia Clelia)..

The Mussurana is a snake with a solidly muscled body.  It has a beautiful deep gloss grey color which radiates a fabulous deep blue iridescence.  The underside is a soft eggshell cream.  It is a powerful constrictor.  The teeth at the back of the jaws are strong and allow it to hold onto its writhing victim while it throws around it those ever-tightening coils.  This is a non-contest, the Terciopelo has little or no chance.  Finally, it succumbs and expires.  The hunter has become the hunted and the frogs have one less problem in their territory.

Mussurana.

Mussurana, (Clelia clelia)

Philip Davison is a Biologist, Writer and Photographer Based In Costa Rica

Cracking New Nymphs and Dwarves   2 comments


Philip Davison. Costa Rica. Blog. Nature Diaries

Wet Nights

The heavy rains have continued through into this week.  The heavens generally open later in the evening which is an ideal situation as the next morning the sun rises with a blue sky which leaves the day free to explore and take photographs. Well that happens on some days but progressively it has been raining late afternoon and sometimes continuing over night into breakfast time.  The creek is running with water again, at least in the upper and lower stretches but it will take a little longer for the full flow to resume.

An Explosion of Nymphs

One noticeable feature of this week has been an explosion in butterfly numbers both in terms of species and individuals.  More particular this has been the case with three particular species of butterfly in the Nymphalid family; the White-banded Peacock, (Anartia fatima), the White Peacock, (Anartia jatrophae), and the Tropical Buckeye, (Junonia evarete).  Not one of these three species is rare or uncommon and they can be found in greater or lesser numbers throughout the year depending upon season.  They do have cyclic emergences which suggest two broods may occur over the course of a year but over the last week significantly all three have suddenly emerged in huge numbers.

Anartia fatima

White-banded Peacock, (Anartia fatima)

Anartia jatrophae

White Peacock, (Anartia jatrophae)

It may well be that the rains arriving in April along with high temperatures have meant that the larval food plant of these three species has been able to produce a lot of vegetative growth which in turn has provided a sufficiently adequate amount of food to support a greater number of caterpillars.  The White-banded Peacock and the White Peacock caterpillars both feed on similar plants, namely those in the family Acanthaceae.  The Tropical Buckeye feeds on plants in the family Verbenaceae but in Costa Rica it is not known of which species.  Significantly all three species are found in open habitat such as grasslands rather than within the forest.  For that reason their presence is more obvious in the gardens around the lodge.

Junonia evarete

Tropical Buckeye, (Junonia evarete)

A New Cracker

As well as all of the peacock and buckeye butterflies flying around there are also large numbers of the Green Urania moths still residing in the locality.  But they are not the only lepidoptera to be observed.  This wet season seems to have been favorable to many other species, some of which live in the forest and others at the top of the canopy.  I have lived in the area for sixteen years and part of my research is the monitoring of butterfly populations.  In that time I have recorded 380 species at ground level in the area.  Some of those species occur regularly but there are others that I have only seen once and then never again.

There are several species of cracker in this locality.  They most certainly are not a commonly observed butterfly.  Last week I was returning to the lodge after photographing some other butterflies when I noticed on the side of a tree a species of cracker that I had not previously recorded from this area, the Red Cracker, (Hamadryas amphinome).  It is always sod’s law that if I see a new butterfly species that I am generally not carrying the camera.  This time I was.  The lighting was good and the subject was in the perfect position so I got a good shot.

Hamadryas amphinome

Red Cracker, (Hamadryas amphinome)

The male crackers typically perch on the side of tree trunks with the head facing down.  The name refers to their habit of emitting an audible cracking sound.  Research has shown that the cracking sound is made following the upsweep of the wings which make contact at high speed at the top of the stroke.  One of the wing veins is expanded which acts as a resonating chamber to amplify the sound of the crack.  It is assumed that the cracking is made by the males as part of the territorial or mating behavior but results are not as yet conclusive.

Sleeping Sulfur

One butterfly commonly seen flying around the garden areas is the Cloudedless Sulfur, (Phoebis sennae).  It bright lemon yellow coloration is immediately catches your attention as it flutters its way across the lawns.  But despite the fact that it is reasonably common it is extremely difficult to photograph.  The adult rarely seems to land and when it does it is only for fleeting moment before it is off again.  You have to be fortunate enough to be in the right place at the right time.

Phoebis sennae

Cloudless Sulfur, (Phoebis sennae)

At night however they sleep, for the most part under wide leaves close to the ground.  As long as you work without too much disturbance this then provides an ideal opportunity to capture its image as it is not moving at all.  Too much light will cause it to wake and it may fly off in a very bewildered fashion.

Confusing Swallowtails

There are two species of butterfly to be commonly found in this area which are almost impossible to tell apart.  They are both commonly known as Giant Swallowtails.  The two species in question are Heraclides thoas and Heraclides cresphontes.  The males can be distinguished under close scrutiny but the females provide more of a challenge.  In fact the best way to distinguish the females is to watch and see which plants they visit to lay their eggs; H. thoas only uses plants in the pepper family; Piperaceae whereas H. cresphontes uses a whole variety of genera in the family; Rutaceae.

Heraclides thoas

Giant Swallowtail, (Heraclides thoas)

The caterpillars are quite distinct and the fact that they feed on different food plants makes identification easier.  They both resemble bird droppings being shiny and brown with creamy patches.  H. thoas has one creamy patch while H. cresphontes has two.  I found this group of H. cresphontes caterpillars quite low to the ground on a small shrub which within a day or two they had consumed and the caterpillars themselves had disappeared.  A bird dropping is not going to appeal as a food source to many animals so the caterpillars can feed in the open without too much concern of being preyed upon by larger predators such as birds and lizards.  The deception might not prove successful against parasites and parasitoids though.

Heraclides cresphontes

Giant Swallowtail, (Heraclides cresphontes), caterpillars

Galling Sight

A close look at some of the plants as you walk around the trails will reveal various oddly shaped structures which suggest something has gone wrong with the leaf development.  To a certain degree this is true.  These weird, and to some people, ugly growths are leaf galls.

Leaf galls are the plants reaction to the invasion of another organism and there are many organisms that can induce gall development including bacteria, fungi, nematodes insects and arachnids.  The appearance of the gall is host specific so for those who study galls, cecidologists, the organism causing the gall can be identified very quickly.  Sometimes an infestation may occur but for the most part the gall producers do not harm the host.

Plant Gall

Unidentified Plant Galls

With insect induced “closed” galls, the adult lays an egg within the leaf tissue.  The egg hatches and when the larva emerges contact between the larva and the meristematic vegetative tissue causes excess cell multiplication thereby forming the gall.  The larva develops within the gall protected by its walls and feeding from the underlying starch and sugar rich tissue.

Because the gall causing agents are so numerous it requires the eye and the knowledge of an expert to be able to effect an identification.  My guess is that these galls were caused by an insect possibly in the Order: Diptera.  I would welcome any input from a gall expert who may be browsing these pages to help reveal the causal organism of these galls.

Lying Low

Bird nests are one of those things that can generally only be found serendipitously.  Hummingbird nests despite their small size are the most commonly seen of the nests as they tend to be built in more open locations either secured to a small branch or fastened with spider web beneath the tip of a Heliconia or palm leaf.

However on occasion something will catch your eye that isn’t all that it seems.  Only about eight feet off the ground just to the side of the trail I found what looked like a tangle of fallen vegetation.  But there was something about the way it was lying in the fork of a small tree that did not appear random.  A look with the binoculars I could see that top of a birds head poking out above a moss-lined cup on top of the tangle.  There was not much to see but I was reasonably sure it was a female Golden-crowned Spadebill.  I returned several times to hopefully get a picture of her sitting on the nest but with no luck.  I didn’t want to cause any disturbance so I just photographed the nest without its owner.

Platyrinchus coronatus

Golden-crowned Spadebill, (Platyrinchus coronatus), nest

Raining Dwarves

One evening in the restaurant following the nightly deluge a small distinctively patterned  snake was found lying on the wall, a Dwarf Boa, (Ungaliophis panamensis).  It is not a snake that is frequently seen as it inhabits the canopy where it can be found occupying the inner recesses of larger bromeliads.  I have found them around the lodge several times over the years.  This one may have been knocked out of the tree tops by the torrential downpour that had just occurred.

Ungaliophis panamensis

Panamanian Dwarf Boa, (Ungaliophis panamensis)

They are called Dwarf Boas because they never grow to a size larger than 2 feet in length.  Due to the small size the adults probably prey upon frogs and lizards found amongst the epiphytic growth at the top of the trees.

Philip Davison is a Biologist, Writer and Photographer based in Costa Rica.

A Poisonous Tropical Tiger   1 comment


Felipe del Bosque Blog July 3rd 2011

 

No Change

The wet season continues with overcast days and nightly rain.  The rain hasn’t been too heavy this week and towards the end of the week we had some nice sunny days with the rain falling at night.  The temperatures continue as expected for this time of year, reaching a maximum in the day of the lower nineties and at night consistently dropping to the lower seventies.

A Walk in the Woods

While I was walking on the Titi Trail last week, at one point I had a Collared Peccary, (Tayassu tajacu), standing right on the path in front of me.  It simply looked at me and then walked into the forest, but only just off the trail.  As I continued on my way, the peccary walked without too much concern slightly in front and to my right.  When I first arrived at Bosque 11 years ago, this situation would never have happened.  As soon as the peccaries caught drift of your presence they would scatter with great speed, teeth clacking and grunting, in the opposite direction.  Now they seemingly couldn’t care less about your being there.

There are two species of peccary on the Osa Peninsula, the Collared Peccary, which we find on the grounds of Bosque del Cabo and the White-lipped Peccary, which inhabits the forests of the the National Park, Corcovado.  Only once in 11 years have I seen the White-lipped Peccaries at Bosque.  That was a herd that had migrated east along the coast from the park and passed by my cabin while doing so.

The Collared Peccary is normally found on the Titi Trail in numbers of 7 or 8, but occasionally as many as 20 have been seen together.  They are generalist feeders, taking lots of fruit and seeds but they will feed on animals as well, grubbing up arthropods from the ground and even rodents and birds.  In the damper areas of Bosque, grows a plant that we are familiar with as a common house plant, Dumb Cane, (Dieffenbachia sp).  These are deadly poisonous plants, the leaves of which contain crystals of Calcium Oxalate, which doesn’t do your kidneys any good.  Collared Peccaries are particularly fond of Dumb Cane and eat large quantities without suffering any ill effects, the digestive systems obviously having evolved to safely metabolize the Calcium Oxalate.

Not that much further along the trail, I could hear the soft whistles of a group of ground living birds, the Great Curassow, (Crax rubra).  It was a group of turkey sized females sporting plumage of mottled creams and browns.  Just like the peccary, they were in no particular hurry.

That has not been the case at night though when I leave the office late.  For the past week, as soon as I step down from the office steps, some startled creature has gone crashing underneath the deck.  I had an inkling of what it might be; we only have one nocturnal animal that will make that kind of noise, somewhat like a tank crashing through the undergrowth, a Nine-banded Armadillo, (Dasypus novemcinctus).  Sure enough, one night, just after the crashing, I could see the armadillo on the other side of the deck where it emerged.  Armadillos have a short term memory of little more than a nanosecond and recommence their noisy activities regardless of whether or not the potential danger has passed.

Cracks are Forming

The Milky Tree that fell last month has now started showing signs of drying out.  All the milky resinous sap that initially leaked out has gone, mostly taken by bees of various species for nest construction.  Now we have the first level of obvious decomposers moving in, the beetles.  Rather than the adults, it is the larvae that feed on the dead wood, hastening its decomposition.  At the minute though lots of species of beetle are pairing up on the face of the now exposed heartwood which is where they will lay their eggs.

Broad-nosed Weevil          Weevils

In the Comfort Zone

The Long-billed Hermit, (Phaethornis longirostris), that had started to construct her nest by the kitchen entrance last week has completed her task and is now incubating eggs.  She is completely unperturbed by the constant comings and goings of the lodge staff in the area, and the traffic is constant all day long.  It could well be that is why she opted to build the nest in that particular location.  The human non-predators may well be seen as keeping any potential predators of her, the eggs or her chicks at bay.  Having said that though, many of the birds’ nests that are built in or around the restaurant area, sooner or later attract the attention of the Tropical Bird-eating Snakes, and they too have little regard for the big pink monkeys wandering around the concrete and stucco jungle.

Long-billed Hermit

Philip is a biologist, writer and photographer as well as the onsite naturalist guide at Bosque del Cabo Rainforest lodge on the Osa Peninsula, Costa Rica.

www.bosquedelcabo.com

Photo Feature

Flying Tigers

One night when I went back to my cabin I was greeted by an unexpected by pleasant surprise.  Two brilliantly colored Tropical Tiger Moths, (Belemnia inaurata), were resting on the screen of my door.  The next day those colors, that the night before had been so bright, now became even more scintillatingly beautiful.  So I had to get a photograph.

Nature tends to produce bright colors for a reason, generally that of communication, either within the species or between species.  Most species of butterfly and moth that exhibit bright and flashy colors are suggesting that you give them a wide berth.  These colors are warning colors and in the case of butterflies or moths you are normally being warned that the insect is packed with poisons.  Some of the brightly colored butterflies we found around the grounds of Bosque, the Heliconiids, contain cyanide.  The Tropical Tiger Moth in the larval stage feeds on plants containing pyrrolizidines, (which damage the liver), and cardenolides, (which cause heart failure).  These are stored in the body and passed through to the adult stage where they serve to make the moth unpalatable.  If a bird or a lizard ignore the warning coloration and feed on the moth, they are rewarded, not with a tasty treat but rather with a foul tasting shock that will have them think twice before taking something sporting those colors again in the future.

Tropical Tiger Moth

Text and Photographs are taken from the forthcoming book:

The Natural History of Bosque del Cabo by Philip Davison

Temperature and Rainfall

Average Daily Temp High 89°F.  Average Daily Temp Low 73°F.

Average Daily Rainfall 0.53 ins.  Total Weekly Rainfall 3.71 ins

Average Daily Temp High 31.1°C.  Average Daily Temp Low 22.7°C.

Average Daily Rainfall 13.3 mm.  Total Weekly Rainfall 93.0 mm

Species List for the Week

Mammals

  • Howler Monkey
  • Spider Monkey
  • Capuchin Monkey
  • Virginia Opossum
  • Nine-banded Armadillo
  • Agouti
  • Red-tailed Squirrel
  • Collared Peccary

Birds

  • Red-lored Amazons
  • Scarlet Macaw
  • Long-billed Hermit
  • Rufus-tailed Hummingbird
  • Stripe-throated Hermit
  • Great Currasow
  • Crested Caracara
  • Laughing Falcon
  • Black-hooded Antshrike
  • Chestnut-backed Antbird
  • Common Paureque
  • Rufus Piha
  • Short-billed Pigeon
  • White-tipped Dove
  • Red-capped Manakin
  • Chestnut-mandibled Toucan
  • Cherrie’s Tanager
  • Great Tinamou
  • Riverside Wren
  • King Vulture
  • Black Vulture
  • Turkey Vulture

Reptiles

  • Barred Ameiva
  • Four-lined Ameiva
  • Golfo Dulce Anolis
  • Clawless Gecko
  • Mediterranean House Gecko
  • Cat-eyed Snake
  • Litter Snake
  • Tropical Bird-eating Snake

Amphibians

  • Marine Toad
  • Red-eyed Green Tree Frog
  • Banana Frog
  • Smokey Jungle Frog
  • Black and Green Poison Arrow Frog
  • Fitzinger’s Rain Frog
  • Stejneger’s Dirt Frog
  • Tink Frog

Butterflies

  • Anartia Fatima
  • Astraptes fulgerator
  • Battus belus
  • Callimormus radiola
  • Cithaerias pireta
  • Colobura dirce
  • Euphyes vestries
  • Eurema albula
  • Eurybia lycisca
  • Glutophrissa drusilla
  • Heliconius erato
  • Heliconius hecale
  • Heliconius ismenius
  • Heliconius sapho
  • Heraclides cresphontes
  • Hermeuptychia hermes
  • Laparus doris
  • Marpesia berania
  • Morpho menelaus
  • Pareuptychia ocirrhoe
  • Phoebis argante
  • Phoebis sennae
  • Pierella luna
  • Pyrgus oileus
  • Saliana esperi
  • Siproeta stelenes
  • Urbanus tanna

 

Plants

  • Black Alligator Tree Flowering and Fruiting
  • Calabash flowering and fruiting
  • Cedrillo Fruiting
  • Clusia Vine Fruiting
  • Dinner on a Plate Fruiting
  • Monkey Comb Tree Flowering and Fruiting
  • Candlestick Plant Flowering and Flowering.
  • Figs Fruiting
  • Lechoso Fruiting
  • May Tree Fruiting
  • Manglillo Fruiting
  • Nutmeg Fruiting
  • Santa Maria Flowering and Fruiting
  • Yayito Fruiting

Smelling a Rat   2 comments


Felipe del Bosque Blog Feb 7th 2011

Boa constrictor

A Light Sprinkling

The temperatures continue to rise with daily highs in the region of 94 °f (23°C).  The rains have all but stopped, any precipitation now being negligible, a result of early morning condensation.  This is regular dry season weather; hot, dry and sunny.  It also means that the forest floor is rapidly drying up.  In the gardens around the Bosque restaurant, the gardening team has set up the water sprinklers which come on at night providing a little light refreshment for the thirsty plant life.

Otter and Skunk

the beginning of the month, generally finds me making that once a month trip into town to purchase another 30 days supplies of non comestibles.  On this occasion, while approaching a small river that we have to cross, we noticed something running upstream in the shallow water.  This time of year the water level is low and therefore too shallow for anything of great size to swim.  This particular creature despite having its head beneath the surface, we could make out as an otter, a Neotropical Otter.  It was running against the current and more than likely chasing small fish.  It came out of the water, turned around, walked back and entered the water again, repeating the cycle of activity.  I have lived here for eleven years and this was my first ever sighting of an otter.

A few days later, while lying in my bed, having just retired for the evening, I could hear something snuffling around outside my cabin.  As I was not quite asleep, I got out of bed, took my flashlight and went outside to see what it could be.  The stems of the heliconias were shaking as whatever it was moved through, so I just stood and waited.  Emerging from the vegetation in front of me was a Striped Hog-nosed Skunk.  It paid me no heed whatsoever and continued on its nocturnal perambulations into the forest.

The Boa Bar – Quite Literally

One night in the restaurant, halfway through the evening meal, a group of seated diners became distracted by movement in the roof above their heads.  Moving sinuously and furtively from the dry leaves of the thatch was a juvenile boa, (Boa constrictor).  It provided not a little consternation and a great photographic opportunity.

Two days later the boa turned up in the aptly named “Boa Bar”.  We had some Danish visitors staying at the lodge who had previously visited us ten years earlier.  On the occasion of their first visit, I had found a large boa with which the two young girls had been photographed, me holding its head.  Now ten years later and in their late teens, they could recreate the scene but with a decade of difference between.

A Profusion of Biodiversity

On one morning tour as the group I was leading exited the Zapatero Trail into the Tropical Garden, we had a big monkey performance.  Spider Monkeys manically made their way swinging through the tree tops, psychotically screaming and screeching as they went, in typical Spider Monkey fashion.  A troupe of Howler Monkeys languidly sat at the top of a large fig tree, tolerant of the Spider Monkey antics, so long as they didn’t get too close.  At a lower level, at the where the forest edge borders the garden, a large troupe of Squirrel Monkeys searched for insect prey.

As the group were watching the monkey display, a beautiful Double-tooth Kite, flew in and snatched from the air a katydid that had been flushed by the monkey activity.  Down on the beach some our visitors had been watching a Mangrove Black Hawk fish a large eel from a pool which it then proceeded to consume.

Dry season activity continues unabated.  Mammals, birds and butterflies are out in abundance.  With every week, the butterfly numbers continue to increase, almost doubling in individual numbers every seven days.  During this week’s butterfly transect count, I recorded 374 butterflies of 40 species in the morning, 225 butterflies of 33 species in the afternoon, giving a total species count for the day of 52 different butterflies.  We have yet to reach the zenith of butterfly activity, so I am expecting those numbers, as incredible as it may seem, to increase substantially over the next few weeks.

Philip is a biologist, writer and photographer as well as the onsite naturalist guide at Bosque del Cabo Rainforest lodge on the Osa Peninsula, Costa Rica.

www.bosquedelcabo.com

Photo Feature

Boa constrictor

Boa constrictors are not uncommonly found around the grounds of Bosque del Cabo.  Smaller juveniles are quite often encountered in and around human habitation where they find small rodents which constitute the bulk of their prey.

Larger individuals are normally found in the forest or in the gardens.  They attain an adult length normally in the region of 6 – 9 feet and a weight of 40 – 60 lbs.  The adults will feed on Agoutis, opossums and the occasional coati.

Although when seen out of context, the coloration of a boa are rich in hue and pattern, when placed on the forest floor amongst dead leaves, it would take a very keen eye to pick out the camouflaged serpentine form which blends perfectly with the background.

Boa constrictor

Text and Photographs are taken from the forthcoming book:

The Natural History of Bosque del Cabo by Philip Davison

Temperature and Rainfall

Average Daily Temp High 93°F.  Average Daily Temp Low 72°F.

Average Daily Rainfall 0.00 ins.  Total Weekly Rainfall 0.02 ins

Average Daily Temp High 33.5 °C.  Average Daily Temp Low 22.3 °C.

Average Daily Rainfall 0.1 mm.  Total Weekly Rainfall 0.5 mm

Species List for the Week

Mammals

  • Howler Monkey
  • Spider Monkey
  • Capuchin Monkey
  • Central American Squirrel Monkey
  • Agouti
  • Neotropical Otter
  • Stripe Hog-nosed Skunk
  • Virginia Opossum
  • White-nosed Coati
  • Red-tailed Squirrel

Birds

  • Red-lored Amazon
  • Scarlet Macaw
  • Great Currasow
  • Lineated Woodpecker
  • Pale-billed Woodpecker
  • Crested Caracara
  • Double-tooth Kite
  • Laughing Falcon
  • Roadside Hawk
  • Rufus Piha
  • Chestnut-backed Antbirds
  • Black-hooded Antshrike
  • Common Paureque
  • Crested Owl
  • Short-billed Pigeon
  • White-tipped Dove
  • Rufus-tailed Hummingbird
  • Fiery-billed Aracari
  • Chestnut-mandibled Toucan
  • Cherrie’s Tanager
  • Bright-rumped Atilla
  • Great Kiskadee
  • Great Tinamou
  • Black Vulture
  • Turkey Vulture

Reptiles

  • Basilisk
  • Four-lined Ameiva
  • Central American Whiptail
  • Golfo Dulce Anolis
  • Clawless Gecko
  • Mediterranean House Gecko
  • Cat-eyed Snake
  • Boa Constrictor
  • Tropical Bird-eating Snake

Amphibians

  • Marine Toad
  • Red-eyed Green Tree Frog
  • Banana Frog
  • Smokey Jungle Frog
  • Milky Frog
  • Black and Green Poison Arrow Frog
  • Fitzinger’s Rain Frog
  • Rough-skinned Dirt Frog
  • Stejneger’s Dirt Frog

Butterflies

  • Adepha basiloides
  • Adelpha cytherea
  • Anartia Fatima
  • Anthanassa ardys
  • Arawacus lincoides
  • Battus polydamus
  • Caligo eurilochus
  • Callimormus radiola
  • Calycopis isobeon
  • Cissia confuse
  • Colobura dirce
  • Dione juno
  • Dryas iulia
  • Eueides aliphera
  • Eueides lybia
  • Eueides procula
  • Euptychia westwoodi
  • Eurema albula
  • Eurema daira
  • Glutophrissa Drusilla
  • Gorgythion begga
  • Heliconius erato
  • Heliconius hecale
  • Heliconius ismenius
  • Heliconius sapho
  • Heraclides cresphontes
  • Hermeuptychia hermes
  • Hyalthyrus neleus
  • Junonia everete
  • Magneuptychia libye
  • Marpesia berania
  • Mechanitis polymnia
  • Morpho helenor
  • Morpho menelaus
  • Morpho theseus
  • Nastra julia
  • Pareuptychia ocirrhoe
  • Parides erithalion
  • Perophthalma lassus
  • Philaethria dido
  • Phoebis agarithe
  • Phoebis argante
  • Phoebis sennae
  • Pierella luna
  • Polites vibex
  • Pyrgus oileus
  • Pyrisitia nise
  • Pyrisitia proterpia
  • Pyrrhogyra crameri
  • Siproeta stelenes
  • Staphylus mazans
  • Temenis laothoe
  • Urbanus simplicius
  • Urbanus tanna

Plants

  • Golden Cortez flowering
  • Calabash flowering and fruiting
  • Monkey Comb Tree flowering and fruiting
  • Black Alligator Tree Fruiting
  • Garlic Tree Flowering
  • Candlestick Plant Flowering.
  • Cannonball Tree Flowering
  • Heisteria fruiting

 

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