Archive for the ‘Costa Rica’ 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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OGRE-FACED SPIDER: STARING YOU DOWN   4 comments


Wildlife, nature, fauna and flora of Costa Rica.

The weather is beginning to change.  There are now more rainy days with brief intervals of sun, generally shining in the morning.  Most of the nights are wet, with the rain beginning in the early hours of the evening then continuing through till dawn.  The rain is not heavy but it is constant.  This will now be the pattern until mid-November.  The opportunities to get out and take photographs is going to become more and more limited as the days and weeks go by.

Ogre-faced Spider

Sometimes you just have to be lucky and find yourself in the right place at the right time.  Many years ago I had taken some photographs of a particular species of spider and since then had been hoping to see this species again to get a close up of one of its startling features, the eyes.  I have come across it several times over the years but, unfortunately, never when I was carrying the camera.  Last week my luck changed and I found one without actually looking for it and I did have my camera in hand.

The spider in question is an Ogre-faced Spider, (Deinopis sp), of the family: Deinopidae.  Once you see the spider in close up then the reason for the name will be revealed.  Those two large, forward-facing eyes give the appearance of a mythical ogre staring at you.

Rainforest animals. Rainforest Spiders. Ogre-faced spider. Deinopidae. Costa Rica.

Ogre-faced Spider, (Deinopis sp), easier to see at an angle

The Ogre-faced spiders are not typical orb-weavers, they belong to a group known as lace-web weavers and have evolved a different means of employing silk to catch prey.  There are only 57 species of Ogre-faced spiders but they are found throughout the tropics.  They have long legs and a long abdomen, (opisthosoma).  If they do move, it is slowly and deliberately.  The coloration matches the tree bark on which they are commonly found hanging in a head down position.  During the day they lie flat against the tree to avoid being seen.  But as the sun sets they move into position and set about constructing the ingenious part of its prey capturing trap which is held between the front two pairs of legs.

These four legs have a dry silk frame strung between them.  Attached to the frame is a net made from sticky elastic silk.  An unsuspecting prey item passing below the spider is in for a nasty surprise.  The spider, connected by a dragline drops and opens the front four legs which extend the net.  It is dropped onto of the victim and when the legs are drawn together again the net closed and ensnares the spiders next meal.  The web is shaken a few times to ensure the prey is completely enmeshed, all the while the spider is wrapping in more silk from the spinnerets and continually biting its prey to inject the venom.  The secured and now deceased prey is held in the palps while the spider feeds and at the same time constructs a new net ready for the next meal to arrive.

Spiders. Rainforests. Costa Rica. Ogre-faced Spider.

The long-legged, long-bodied Ogre-faced Spider

The feature I was interested in were the eyes.  At 1.4mm in diameter, these forward-facing eyes are the largest simple eyes possessed of any land invertebrate.  The eyes have an equivalent camera f/stop of 0.6 which enable them to see very well in dark conditions, the time when the spider hunts.  This, combined with retinal receptors capable of absorbing the smallest amount of ambient light, 2000 x more than other spiders, means they can hunt in, what to you and I, is total darkness.  You can’t see the spider but the spider can see you.  Also, this one was a male as can be seen from the enlarged pedipalps under the front of the head.  These are used during spider mating.

Rainforest animals. Rainforest Spiders. Spiders. Deinopis sp. Ogre-faced Spider. Costa Rica.

Now you can see those eyes and the features that give it the name; Ogre-faced Spider

Weirdness on the Web

It has been a spidery kind of week.  When I was out walking the trails I noticed a small web strung across the path with what I first thought was a small spider removing the papery veil of a Jacaranda seed that had landed there.  In the past I have seen various orb-weavers cutting the silk securing an unrequired piece of material that had land in the web, hold it out with their legs until free of the web and let it drop to the ground.  Not too far down the same trail I saw a similar thing so I decided to take a closer look.  The spider itself was very small and with the naked eye it looked strange, I had not seen this species before and could not quite make out the form.  Something just wasn’t right.

Rainforest animals. Rainforest Spiders. Micrathenidae. Micrathena gracilis. Costa Rica.

Spiny Micrathena hanging from web, viewed from behind

I took several photographs and looked on the camera screen.  The body of the spider was unlike any I had previously seen.  The abdomen, (opisthosoma), was drawn up dorsally and expanded laterally.  It was covered in a series of fleshy, thorn-like protuberances.  I was looking at a Spined Micrathena, (Micrathena gracilis).  During the course of the day I found 3 of these spiders, which is strange because I had never seen this species before.  Later, when back online and researching more information, I learned it is quite common and widespread.  Oh well, new for me and happy to have finally made its acquaintance.

Rainforest animals. Rainforest Spiders. Micrathenidae. Spiny Micrathena. Costa Rica.

Dorsal view of Spiny Micrathena Spider

Only a few meters down the trail from where I photographed the Spined Micrathena I found another web traversing the path at about 6 feet above the ground.  Sitting in the center was yet one more spider that I was unfamiliar with.  I knew it was one of the Spiny-bodied Spiders, of which I have found a variety of different species over the years.  Unlike Micrathena gracilis above, most Spiny-bodied Spiders are brightly colored and elongated with spines and thorns projecting from the body, sometimes giving them an arrow-shape.  I knew this was a Micrathena, the body was long with black centered red spots on a yellow background and with only two more fleshy spines pointing backwards from the abdomen.  Extensive searching failed to produce a name for this species.  So two new spiders in one day and within several feet of each other.

Rainforest animals. Rainforest Spiders. Spiny-bodied Spider. Micrathenidae. Costa Rica.

Strange Spiny-bodied Spider, (Micrathena sp), awaiting identification

Finally I noticed a small web strung not too far above my head in the open garden area.  In the center of the web was a small brightly-colored but very distinctively spider.  The abdomen was vivid lemon yellow with a series of black spots drawn out sideways into an oval shape bearing ferocious looking thorns around the edge.  This was another Spiny-bodied Spider, (Gasteracantha cancriformis).

Rainforest Spiders. Rainforest animals. Gasteracanthinae. Spiny-bodied Spider. Costa Rica.

Spiny-bodied Spider, (Gasteracantha cancriformis)

They are a very common species but are so small that you generally don’t notice them until you walk into the web.  To avoid this situation the silken strands securing the web are flocked with fluffy pieces of silk to make it more obvious to larger creatures.  They come in various color, yellow, white and red being the commonest.  They are very widespread, being found from southern U.S. to northern Brazil and everywhere in-between including the Caribbean Islands.

It is a very short-lived spider; the females die after producing an egg cocoon and the males die a short time after mating.  In certain locations it is another spider that has a reputation it does not deserve.  Some of the native populations regard it as being very venomous.  It is quite harmless.

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

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

Sun and Moon, Bananas and Lichen.   2 comments


Philip Davison. Costa Rica. Blog. Nature Diaries

Sunny September

The clement weather conditions are continuing to prevail.  The rain we are receiving is most certainly intense but by no means prolonged.  If there is one day of rain it is being followed by two days of sun.  This time of year there are very few visitors.  September and October are not big holiday periods.  For anyone who does want to visit Costa Rica at this time of year you can certainly avoid the crowds but you also run the risk of being confined to your cabin unless you want to suffer a constant soaking.  For those of us who do live here then the quiet time and unseasonably dry and sunny conditions give us time to go and explore a little more or in my case catch up with the writing.

I’m Lichen That

One night when I was out doing my nightly frog counts I came across one of the Anolis lizards that I see more often up in the canopy, a Lichen Anole, (Anolis pentaprion).  This individual was sleeping but when I turned the lights on to video the creature in its state of slumber the instant change from night to apparent day woke it.  Not only did the lizard stir but the increase in light levels drew in some of the insects including one of the few species of night-flying wasps, Apoica pallida.  It landed near the lizard’s head so presenting itself as an easy meal the advantage of which it was not going to refuse despite having only just being disturbed from its sleep.  With a quick snap of the jaws the wasp was caught, chewed up and down the body and then swallowed.  The Anolis then soporifically walked up the small branch on which it was clinging, climbed atop a leaf into a darker location than it was now finding itself, closed its eyes and went back to sleep.

Anolis lizards are a very diverse genus with many closely related genera belonging to the family: Polychrotidae.  There are well over 200 species of Anolis and each species quite often is divided into a number of subspecies.  Anolis lizards are similar to geckos in that they have an anatomically specialized structure to the toes, (lamellae), that allow then to climb with ease including smooth vertical walls and even panes of glass.  Anolis lizards are generally small and unless you notice some movement as they jump through the vegetation then they can easily be overlooked.  In terms of ecology smaller species inhabit the lower levels of the forest and conversely larger species the higher levels.

Anolis pentaprion

Lichen Anole

Although the family is species rich, it is not always easy to identify the individuals to species level.  One factor that does help is the males have a loose flap of skin under the chin called a dewlap.  Thankfully each species has a different color dewlap, particularly pronounced in this area.  The loose skin is attached to a rod of cartilage fixed at the jaw over which the lizard has muscular control.  The lowering of the cartilage extends the skin revealing the brightly colored flag which is in stark contrast to the more usual body color and it is used to intimidate and scare rival males from the territory or used to court females.  Certainly if you see that bright flash of color appear as if from nowhere then there will be a second individual you may not be so aware of but it will be somewhere close by in the vicinity.  The dewlap of the Lichen Anole is a deep purple edged with magenta and is not as large as in some other species.  Most females do not possess a dewlap and because there is a strong sexual dimorphism can prove a little more difficult to identify.  Here on the Osa Peninsula there are only seven species of Anole and they are all fairly distinct in appearance both male and females.

Many Moons

There are two particular species that seem to have reacted to this year’s slightly abnormal weather conditions.  One is a butterfly and the other is a frog.  They have both been recorded in numbers in excess of those normally found.

The Luna Satyr, (Pierella luna), is a largish brown butterfly that is normally found throughout the year but for the most part as solitary individuals or in small groups.  It is found flying very close to the forest floor in the dark, dank, shady conditions beneath the forest canopy.  You will quite often only notice it when it momentarily passes by your feet, wings beating slowly, as it moves from one side of the path to the other.  It will disappear under the vegetation and when it settles the muted grays and browns of its now still wings blend it immediately into the background.  It prefers the denser aspect of secondary forest as opposed to the more open situation beneath primary forest.  This may have something to do with the distribution of its larval host plant, species in the family: Heliconiaceae, many of which can be found in secondary forest habitat.

This year when walking along trails through secondary forest Luna Satyr could be found in huge numbers much larger than experienced before.  I am not sure what triggered the population explosion but the adults have not been hard to find, sometimes in groups numbering ten or more.  The slightest disturbance caused by your footfall will have them momentarily take to the air before quickly alighting once more on the ground.

Pierella luna

Luna Satyr

A Big Bunch

The Banana Frog, (Dendropsophus ebreccatus), is one of those small tree frogs that you can more or less guarantee you will see if you go to the pond at night.  They are ever present throughout the year.  At the height of the amphibian breeding season which starts when the rains arrive in April, gets into full swing in May and draws to a close by the end of August, the Banana Frog males can be both seen and heard in reasonably large numbers every night.  Those numbers reduce outside of the breeding season to the point where during the dry season it might only be one forlorn male out calling but there will always be one.

The males emerge as the sun slowly sinks beneath the western horizon.  They set up their territories on the Water Lettuce or Water Hyacinth and call vigorously with a protracted “Eeeack”.  The larger egg bearing females emerge a little later, select a male on the quality of his call, makes her way over to the male of choice, they pair up and later she lays a sheet of small jelly coated eggs on the surface of a leaf which the male fertilizes.  The eggs develop here for 7 or 8 days, the tadpoles wriggle free and slip below the surface of the water from where they will emerge about 8 weeks later as small froglets.

Whereas this time of year when all the other frog species have either disappeared from the breeding pond or are present in only small numbers, the Banana Frog has seen a surge in numbers.  There are presently in the region of 20 calling males every evening.  It could well be that they are taking advantage of the lack of competition from other species, although there are not too many other species that do use the Water lettuce, (Pistia stratiote), and Water Hyacinth, (Eichhornia crassipes).  The tadpoles of other frogs do have to compete for space and food once they have entered the water, some of which may be larger and/or more voracious than D. ebreccatus tadpoles.  It may simply be the fact that there is still a lot of rain which is perfect for the eggs but that is the norm every year.  Whatever the reason if you could down to the pond at the minute after sunset you will be greeted by a vociferous chorus of amorous Banana Frogs.

Dendropsophus ebreccatus

Banana Frog

Seeing You Walk for the First Time

Last week I happened across an insect that has proved to be somewhat difficult to identify.  What initially caught my eye were the colors, most strikingly the bright yellow.  The head was small but the body was long and soft.  The wings too were brightly colored but in green.  My first thoughts were that it was some kind of Phasmid or Walking Stick, more precisely a winged walking stick.  It did not seem to be disturbed when I moved it from the bare white stucco wall where its colors were making it rather conspicuous to some nearby vegetation where it was less obvious.  Not moving is part of a Phasmids game plan though.  I took some photos and headed off to my reference library.

Phasmid

Winged Walking Stick

As with most insects that I see for the first time after 16 years of living here I just know the identification is going to be difficult.  Insects are so prohibitively numerous in number of species, especially tropical insects.  The reference material available is limited and by no means exhaustive.  So after some searching I was not really any further forward than still being confident it was a winged phasmid.  Time to scour that great resource the internet.  Scrutinizing photo after photo all I could conclude that it was a winged phasmid but there was nothing I could see that looked remotely like this individual.  So if there are any phasmid experts that may be reading this and could enlighten me as to a genus or species I would love to hear from you.

Phasmid

Winged Walking Stick

Philip Davison is a biologist, writer and photographer based in Costa Rica.

 

The Dragon Hunters   Leave a comment


Philip Davison. Costa Rica. Blog. Nature Diaries

Monday 18th January 2016

Hair Trigger

Arachnid. Costa Rica.

Spiders are an amazingly diverse group of animals, the eighth most diverse group of animals of the planet in actual fact.  It doesn’t take long while poking around in the undergrowth to come across a spider.  Some build webs and some don’t but they can all spin silk, the orb weavers having the ability to spin upto seven different types of silk.  The non-orb weavers tend to be ambush predators, remaining motionless in a strategic location where potential prey may wander innocently by unaware of the imminent life threatening danger.  The ambush position could be on the side of a wall, atop a leaf or sitting on a flower head.

Arachnid. Costa Rica.

This Wandering Spider, (Cupiennius sp), was sitting perfectly still on a blank white wall at night.  As many spiders are nocturnal predators the eyes play a lesser part in the identification and capture of a meal but that does not imply the spider is without the means by which to locate the exact location of its prey.  The body, which at first sight looks smooth, upon closer examination can be seen to be covered in hairs of different lengths.  These hairs form part of a battery of sensitive sense organs responsive to touch, vibration and moving eddies of air currents that allow the spider to detect a passing meal in the darkness.

Wandering Spider. Araneae. Ctenidae. Costa Rica.

The majority of hairs covering the body, which give most people the heebie-jeebies with regards to spiders, are tactile and touch sensitive, the stimulus of which will cause the spider to attack or run away.  Between the shorter hairs, particularly on the legs are long fine hairs called trichobothria.  These are super sensitive to the slightest movement in air currents which can be a giveaway for any larger creature passing by which could make a nice meal.  The Wandering Spiders can even detect insects such as moths flying overhead which they jump and grab straight out of the air.

For those more stealthy prey items whose movements are too slow to disturb the air, they cannot avoid causing small vibrations of the substrate and the spiders are attuned to this also.  Around the body but more particularly around the leg joints are slit sense organs which allow the spider to detect any vibrations moving through the substrate upon which it is placed.

Whereas the Wandering Spiders rely on their tactile senses at night during the day there are spiders that actively hunt down their prey visually.  The Jumping Spiders prefer to hunt in full sun.  The most obvious feature are the large anterior eyes with which they can locate and subsequently stalk their victims.  They stealthily approach to the point where the potential meal is within striking distance.  The spider braces itself and then pounce.  The fangs are embedded upon impact, pumping venom into the victim which is held in a death grip by the front pair of legs.

Salticidae. Jumping Spider. Costa Rica.

Hunting the Hunters

The spiders may be highly adapted carnivores with specialized hunting techniques but they too in turn have predators specialized to catch and eat them.  Not the least of these are the giant Helicopter Damselflies, (Megaloprepus caerulatus), the largest damselflies on the planet.  They can be seen flying along the sunlit trails through the forest.  The peculiar motion of the blue/black tipped wings gives the impression of rotating helicopter blades.  What may at first seem like a somewhat erratic flight pattern actually has design.  The more astute observer will notice that they have the ability to fly vertically up and down as well as horizontally in and out.  But what are they seeking?  The large eyes and acute vision are scanning spider webs in front of which they momentarily hover scanning for the silken structures builder.  Once located the spider is grabbed in the legs of the damselfly which goes into reverse gear before biting off the spiders head and legs to finally gorge itself on the soft body parts.

Helicopter Damselfly. Pseudostigmatidae. Costa Rica

The damselflies can be recognized when they alight by the habit of folding the wings together over the body.  Their cousins, the dragonflies keep the wings held out to the sides when at rest. During the day it is not too often that they do rest.  Each individual has a perch from which it frequently takes off to investigate any passing creature that might make a meal or another dragonfly that might prove to be a mate or another dragonfly that might be a rival for that meal or mate.  They make aerial sorties swooping at speed, hovering in place and if unmoved to action return to the perch for a short while before they are off again on another sortie.

Dragonfly. Libellulidae. Costa Rica.

They differ from the more delicate damselflies not only by how they hold their wings but also in the structural placement of the eyes.  Damselflies have two large compound eyes widely separated on either side of the head.  Dragonflies have two large compound eyes that meet together for a greater or lesser part of their margins on top of the head.  However no matter where the eyes are placed they allow for excellent diurnal vision which combined with the unsurpassed aerobatic proficiency make these some of the masterful airborne hunters.

As we move into the dry season the hot and parched conditions stimulate many of the plants into flowering.  This is most certainly true of the orchids.  There are two orchids that can be seen blooming at the moment in the area.  One is a non native terrestrial orchid, the Bamboo Orchid and the other is a native epiphytic orchid.

Orchidaceae. Costa Rica.

The Bamboo Orchid is a native of South East Asia but is planted in many parts of Costa Rica as a beautiful ornamental edging plant.  Bamboo refers to the long erect stalk that resembles that a of a bamboo grass.  The attractive purple flowers appear throughout the year giving a nonstop display of color for the back of a flower border.

Orchidaceae. Costa Rica.

The majority of orchid species in Costa Rica are epiphytic, that is they grow on the outside of trees without harming them.  Generally to see orchids you need to be at the top of the canopy, 88% of Costa Rica’s 1400 orchid species are to be found there.  Many of the orchids flower from December into January but some may be seen flowering at any time of the year.  This particular specimen was found growing close to the ground near the base of a large tree. Due to the diversity of genera and species the identification of orchids, like so many tropical plant and animal taxa, is the realm of specialists.  For most visitors it is enough to see and enjoy the exotic blooms should you be lucky to encounter them.

Philip Davison is a biologist, writer and photographer based in Costa Rica.

 

Mixed Fruit and Nuts   Leave a comment


Felipe del Bosque Blog January 14th 2013

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A Waterless Place

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This has been another week of bright sunny days and rising temperatures.  There has not been a drop of rain this week.  The level of water at the ponds is dropping.  There are fewer species of amphibian out but now the Savage’s Thin-fingered Frogs have started to congregate around the pond simply because it is a damper than the surrounding areas.

At night the Cat-eyed Snakes can be seen lying around the edge of the pond waiting for the froglets to emerge from the water.  You can sometimes see them with their heads beneath the surface of the water picking off the tadpoles which hang motionless in the nighttime shallows.

Colorful Confetti

The sun continues to bring out the butterflies which are increasing on an almost daily basis both in terms of numbers and individuals.  It doesn’t take much to stroll around the grounds with your camera at the ready to get some nice shots, the earlier the better before they warm up.

Last week I got some nice photos of Chlosyne theona which was out in full sun on the side of a hillock.  This week it was in exactly the same place so I took some more shots.  It wasn’t easy being in full sun with a constant breeze blowing against the butterflies wings.  Not too far away, again settled close to the ground thus requiring some awkward but nonetheless stealthy maneuvering to get close was a Pyrisitia nise.  These small yellow butterflies seemingly never settle so here was an opportunity to snap an image.  The problem was the wings being parallel with the bright sun making it difficult to truly capture the bright lemon yellow coloration.  Not so far away was a White Peacock, (Anartia jatrophae).  It refused to land so that I could get the right angle to photograph the spread of its wings but there will be many other days and more opportunities over the coming months to do so.

Chlosyne theona

Pyrisitia nise

Anartia jatrophae

A Bouquet and a Basket of Fruit

As the conditions become progressively drier, the trees begin to flower.  At this point in time as you walk through the forest there are places along the trails where the ground is covered in a carpet of fallen yellow flowers dropped from the overhanging branches of the Garlic Trees, (Caryocar costaricensis).  This is by no means the only flower to be seen but it stands out because of its bright golden color.  Not so intense in color but noticeable due to it strangely shaped blossoms are the flowers of the Hule or Rubber Tree, (Castilla tunu).  The soft gold velvety male inflorescence is shaped like a folded tortilla filled with the stamens. Currently it is possible to see the fruits lying on the ground too.  These come from the pollinated female flowers and resemble a miniature basket filled with green pairs.  When cut into, the trunk of the tree exudes white liquid latex that is processed to produce rubber.

Castilla tunu male flower

Castilla tunu fruit

A Hint of Spice

One of the distinctive fruits decorating the forest floor at the moment is that from the Fruta Dorada, the Golden Fruit Tree better known as nutmegs.  The nutmeg we use in a culinary situation is an Indonesian species belonging to the same Family Myristicaceae.  There are four species of nutmeg, (Virola spp), to be found within the forests of Bosque del Cabo.  The species that is currently fruiting is V. guatemalensis.

Virola guatemalensis

When the fruit first falls to the ground it is a green to yellow in color hence the golden fruit.  The shell is closed holding the seed hidden within.  But as it dries, it splits revealing a visceral looking membrane that provides a bright flash of red.  Red is a very important color in the forest.  It is the complimentary color to green.  Whereas green is a very cool color, red is a very hot color.  Birds having acute color vision will see fiery red a long way off standing out vividly against the cold verdant background.

Virola guatemalensis

Particularly with the nutmegs they are attracting the attention of Chestnut-mandibled Toucans, (Ramphastos swainsonii).  Toucans are fruit eating birds that gulp the fruits down whole.  The red covering to the seed is called the aril.  It is very tasty and nutritious.  The toucan digests the aril but is now left with a gut full of big heavy seeds which is not conducive to flight, so the bird regurgitates up the seeds thereby distributing them some distance from the parent tree.  In effect the tree attracted the bird in using the color red, gave it a nice tasty reward in the form of the aril to eat the seed which is then transported away and dispersed.

The Indonesian nutmeg, Myristica fragrans, is used in two ways.  The seed is dried and ground to give the familiar spice nutmeg whereas the aril is dried and ground to give the spice mace.  Certain of the South American nutmegs when tapped give a sap which is used in tribal rituals; the least of its effects being that of one of the most powerful hallucinogens that we know of.

Shady Characters

One other plant that has previously found their way into these pages has been in flower again.  One the Titi Trail you will see many corky vines woven within the fabric of the other plants.  This characteristic texture belongs to the Family Aristolochiaceae.  There are 4 species on the Osa Peninsula all belonging to the Genus Aristolochia.  They are unmistakable when in bloom as the flowers come directly from the side of the vine and stand erect like a Dutchman’s pipe which strangely enough is what they are called.

Aristolochia goudoti

The mottled purple blooms give off the scent of rotten meat which consequently attracts the attention of carrion flies.  The flies land expectantly on what they think will provide a good meal for their larvae.  The inner surface of the flower is slick so the inveigled fly slips down into the interior chamber of the bloom.  Backward pointing spines bar its escape so there the insect remains trapped.  Had it already suffered the same indignant experience it would be carrying the pollen from another bloom which is transferred effecting pollination.  The flower then wilts allowing the fly to go free carrying a fresh batch of its own pollen hoping that the fly can be duped yet again.  Following successful pollination then the fruit capsules are formed holding the seeds which are flat and wind dispersed.

Aristolochia goudoti fruit

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

Figs for All

Another tree that can be seen producing fruit, although in this case there is no specific season, is one of the many species of Fig Tree, (Ficus spp).  Figs are an important food source not the least because within any one population of a fig species at least one individual will be fruiting at some point during the year.  They produce such a copious amount of fruit that they feed so many animals in the forest.

Ficus insipida

Tropical rain forests are generally found to be windless places.  For that reason the plants largely have to rely on animal agents for pollination and seed dispersal.  Due to the fact that there is such a high number of tree species within any given area, not only do the trees have to attract an animal to come to them but also then offer the animal a reward to stop it going to any other species of tree.  The figs have taken this to an absolute extreme.

Every species of fig tree has it own individual species of fig wasp, (Family Agaonidae), to pollinate it and there are approximately 800 different species of fig to be found worldwide. The fig is a synconium and inside each fig there are three types of flower; male flowers, female flowers and sterile flowers called gall flowers.  The gall flowers are the reward, which is where the female wasp will lay her eggs.  The first eggs to hatch are the wingless males.  They move around inside the fig looking for the as yet undeveloped females.  They find them and mate with them.  The male then bores a hole out of the fig and dies.

Later the female fig wasp emerges but her emergence coincides with the male flowers coming into season so as she travels around inside the fig she gets coated with pollen.  She makes her way out of the hole the males bored out and then she has to fly off to find a tree where the female flowers are in season.  This is achieved by following a pheromone trail released by the young fig.  The fig has an opening, the ostiole, which is lined with downward pointing scales that allow entry in one direction only, from the outside to the inside.  The female enters and loses her wings as she does so.  The pollen is transferred from her body to the female flowers thereby pollinating the fig.  The gall flowers are short stalked female flowers into which the ovipositor of the female wasp can reach to lay eggs.  Once she has finished transferring the pollen and laying her eggs, the female wasp dies.  Several weeks later the larvae that have developed within the gall flowers will emerge and the cycle will repeat.

The fig and the fig wasp have become mutually dependent on one another for their very existence.  Due to the fact that so many animals rely on the crop of figs that relationship produces it is known as one of the keystone dependencies of the forest.

One the fig has been pollinated it produces tiny seeds which the tree has to get through the guts of the animals eating them very quickly to stop the digestive juices breaking down the seed coat.  To aid in the rapid passage of the seeds through the alimentary canal of the animals eating them, the pulp of the fig contains a laxative.  But it has relied on large mobile animals such as birds, monkeys and bats that will have moved some distance from the parent tree before they defecate and disperse the seeds.

Sometimes the figs produce more fruit that even all the visiting animals can consume.  As you walk through the forest you may find yourself under a rain of falling figs, each one crashing through the underlying foliage before hitting the ground.  This benefits many ground living creatures such as peccaries, agoutis, pacas, opossums and rodents.  As the figs rot the heavy scent of fermenting fruit attracts in butterflies such as blue morphos which imbibe the liquor.  Ultimately the mould spores germinate and within a short space of time the fig will have become a fuzzy white ball of threadlike mould mycelium.

Ficus insipida

Text and Photographs are taken from the forthcoming book:

The Natural History of Bosque del Cabo by Philip Davison

Temperature and Rainfall

Average Daily Rainfall 0.00 ins.  Total Weekly Rainfall 0.00 ins

Average Daily Rainfall 0.00 mm.  Total Weekly Rainfall 0.00 mm

Highest Daily Temp 90°F.  Lowest Daily Temp 74°F.

Highest Daily Temp 32.0°C.  Lowest Daily Temp 23.2°C.

Species List for the Week

Mammals

  • Howler Monkey
  • Spider Monkey
  • White-faced Monkey
  • Kinkajou
  • White-nosed Coati
  • Nine-banded Armadillo
  • Alfaro’s Pygmy Squirrel

Birds

  • Red-lored Amazon
  • Scarlet Macaw
  • Brown Pelican
  • Great Curassow
  • Crested Caracara
  • Mangrove Black Hawk
  • Pale-billed Woodpecker
  • Chestnut-backed Antbird
  • Short-billed Pigeon
  • White-tipped Dove
  • Rufus Piha
  • Blue-crowned Motmot
  • Stripe-throated Hermit
  • Red-capped Manakin
  • Chestnut-mandibled Toucan
  • Bright-rumped Atilla
  • Dusky-capped Flycatcher
  • Great Kiskadee
  • Green Honeycreeper
  • House Wren
  • Great Tinamou
  • Black Vulture
  • Turkey Vulture

Reptiles

  • Barred Ameiva
  • Basilisk
  • Cat-eyed Snake
  • Central American Smooth Gecko
  • Central American Whiptail
  • Common Anole
  • Dwarf Boa
  • Four-lined Ameiva
  • Golfo Dulce Anolis
  • Litter Skink
  • Mediterranean House Gecko
  • Tiger Rat Snake

Amphibians

  • Fitzinger’s Rain Frog
  • Marine Toad
  • Masked Smilisca
  • Milky Frog
  • Red-eyed Green Tree Frog
  • Rough-skinned Dirt Frog
  • Savage’s Thin-fingered Frog
  • Stejneger’s Dirt Frog

Butterflies

  • Adelpha heraclera
  • Anartia Fatima
  • Anartia jatrophae
  • Archaeoprepona demophon
  • Battus belus
  • Calycopis isobeon
  • Chlosyne theona
  • Consul fabius
  • Dryas iulia
  • Eueides aliphera
  • Eueides lybia
  • Glutophrissa drusilla
  • Heliconius erato
  • Heliconius hecale
  • Heliconius ismenius
  • Heliconius sapho
  • Heraclides cresphontes
  • Hermeuptychia hermes
  • Morpho helenor
  • Morpho Menelaus
  • Pareuptychia ocirrhoe
  • Parides erithalion
  • Pierella helvina
  • Philaethria dido
  • Phoebis sennae
  • Pyrgus oileus
  • Pyrisitia nise
  • Pyrrhogyra crameri

Plants

  • Alamandra  cathartica Flowering
  • Alpinia purpurata Flowering
  • Apeiba tibourbou Flowering
  • Arachis pintoi Flowering
  • Aristolochia gouldi Flowering and Fruiting
  • Arundina graminifolia Flowering
  • Attalea rostrata Fruiting
  • Bauhinia variegata Flowering
  • Cascabella thevetia Flowering and Fruiting
  • Citrus spp  Fruiting
  • Clusia rosea Flowering and Fruiting
  • Clusia vallerii Flowering and Fruiting
  • Cocos nucifera Flowering and Fruiting
  • Crestentia alata flowering and Fruiting
  • Costus speciosus Flowering
  • Couroupita guianensis Flowering and Fruiting
  • Dypsis lutescens Flowering and Fruiting
  • Etlingera elatior Flowering
  • Ficus citrifolia Fruiting
  • Ficus insipida Fruiting
  • Jacaranda mimosifolia Flowering
  • Heliconia chartacea Flowering
  • Heliconia latispatha Flowering
  • Heliconia pogonantha Flowering
  • Heliconia psittacorum Flowering
  • Heliconia rostrata Flowering
  • Hibiscus rosa-sinensis Flowering
  • Hymenaea coubaril Fruiting
  • Hymenocallis littoralis Flowering
  • Ixora coccinea Flowering
  • Lantana camara Flowering and Flowering
  • Lagerstroemia speciosa Fruiting
  • Morinda citrifolia Fruiting
  • Musa acuminate Flowering and Fruiting
  • Nephelium lappaceum Fruiting
  • Piper auritum Flowering and Fruiting
  • Piper nigrum Fruiting
  • Piper umbellatum Flowering and Fruiting
  • Pleiostachya pruinosa Flowering
  • Plumeria rubra Flowering
  • Psychotria sp Fruiting
  • Stachytarpheta frantzii Flowering
  • Virola guatemalensis Fruiting
  • Zammia sp Flowering

 

 

New Ways of Falling from Grace   3 comments


Felipe del Bosque Blog July 16th 2012

How The Mighty Have Fallen

So far the wet season has proved to be a little unpredictable.  Up until the beginning of the week we still had not had a great deal of rain.  The days were bright and sunny followed by 2 or 3 days of heavy cloud cover but still no rain.  Towards the end of week that all changed.  There were 3 or 4 nights in a row where the visitors were treated to the most spectacular thunderstorms.  The storms came straight in off the sea and so the thunder and lightning were simultaneous.   The rain was subsequently measured in several inches for the period of one cloud burst.

One evening at the normal 6:00 pm downpour time, a terrible roaring sound started low down near the cliff edge.  The sound intensified until it sounded like a freight train was heading straight for the bar.  Wind of this ferocity is normally a portent of exceptionally heavy rain that is following in behind.  It did rain but not with the deluge we were expecting, the wind too eventually died down.  We thought we had been spared what potentially could have been a serious ravaging.  It wasn’t until a few days later when I went for a walk on the Zapatero Trail that I could see that had not been the full story.  The main event had hit the forest and as I made my way around the trail, every 100 yards or so my path was blocked by a fallen tree.  Between the fallen trees the path was littered with dead branches.  Off the trail yet more massive arboreal giants had tumbled, their huge forms now laid prone by the force of the short lived squall.  In 12 years of walking the trails on an almost daily basis I had never seen so much sylvan devastation.

The trail maintenance teams went to work clearing out all the fallen timber.  These occasional catastrophic events are all part of the cycle in the forest.  Now there are large gaps in the canopy so the microclimate at the forest floor will have changed; temperature goes up, light levels increase and humidity drops.  All of this acts as a spur for the germination of a lot of the pioneering species of tree which are lying as dormant seeds in the ground just waiting for this situation to occur before rapidly growing to fill the gap which they do within in a very few years.

All the saplings of those shade tolerant tree species have, over many years, stored a lot of energy in their roots systems and then waited patiently in that state of suspended animation for this kind of event to take place.  They are spurred into re-growth, eventually overshadowing the pioneering species as they make their way up to the uppermost level of the forest where their crowns spread and to block the light from penetrating to the forest floor.  There they will stand in statuesque grandeur until perhaps 100 years from now they will ultimately suffer the same fate as those forest giants that preceded them.

Something New

This week there have been no actual Puma sightings but that does not mean there are not around.  The alarm call of the Spider Monkeys has been heard echoing around the grounds at various different locations so even if we haven’t seen them from the ground, the monkeys have certainly been able to see them from the tree tops.

This week a new bird turned up and that was not hard to see.  Standing in the restaurant one morning I could hear a call that I was not familiar with and it was coming from just outside in a Guava Tree.  I went out to take a look and there was one of the Euphonia species but this one was strangely unfamiliar.  Looking through the binoculars I could see it had a small yellow cap but the most distinctive feature was that the whole of the neck was yellow, there was no continuous purple collar.  This limited the choice and I was pretty sure I was looking at a Yellow-throated Euphonia, (Euphonia hyrundinacea), which is exactly what is was.  From the day of its arrival it has been in the same location in the Guava Tree every morning.  It is not alone; there is a female companion who has a slightly different call.  In fact they appear to have made a nest in a palm tree next to their perch.  It is described as very rare in Pacific Lowlands so we are lucky to have it take up temporary residence within earshot of the restaurant.

The Euphonia was not the only new record for the lodge this week.  One night when I went back to my cabin, I proceeded to open up the laptop and do a little more writing before going to bed.  I noticed on the wall to my left a small roosting butterfly that had settled for the night.  Just the same as the Euphonia, I did not immediately recognize the tiny nocturnal squatter, I could see it was one of the Riodinids or Metalmarks but not one I had ever seen before.  As it was motionless no more than 2 feet from my arm it made an easy photographic opportunity.  So I picked up the camera, took the shots, put the camera away and continued my writing.

Calospila martia

Next day the butterfly was flying up and down against the screen of my window so held out my hand and let it settle on my finger whereupon I took it outside and liberated it to fly off into the forest.  Later I looked at the photos with the intention of making an identification.  The butterfly, although small, was distinctly marked with large orange bars traversing the forewings.  It didn’t take long to arrive at the species name, Calospila martia.  The interesting thing is that, according to Philip J. DeVries in his book “The Butterflies of Costa Rica Volume II the Riodinidae”, this butterfly has only ever been recorded from one location on the Atlantic lowland rainforest of Costa Rica, never from the Pacific.  It is found in Panama and its distribution suggests it should be found in this area too, but there are no records.  It could well be that Bosque del Cabo has the first recorded sighting of this species for Costa Rica outside of its only other previous known location.  I await confirmation.

Calospila martia

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

 Fighting For Attention

Activity at the pond at night is cyclic in its intensity.  Some evenings the area and vegetation around the water’s edge is full of calling frogs.  If a lot of spawning has taken place, over the following nights the amphibian activity may die down but they their presence has been replaced by large numbers of Cat-eyed Snakes which venture forth to feed on the now freely available food source.  Generally on a nightly basis you can still find Marine Toads, Red-eyed Green Tree Frogs, Banana Frogs and Smoky Jungle Frogs.  One or two other species may be thrown into the mix; Olive Tree Frogs and more particularly Gladiator Frogs.  The predators of the frogs and their eggs will be around in greater or lesser numbers too; the already mentioned snakes but also large Wandering Spiders.

Last week when I was out and about on one of my nocturnal walks I found a Salmon-bellied Racer settling down for the night on top of a leaf.  Young Basilisks are always found sleeping on vegetation over the water.  My mission on this particular evening was to photograph some of the Amblypygids or Tailless Whip Scorpions.  Once the sun has gone down there are normally a good few sitting on the exposed banks on the side of the road.  I duly arrived at the spot where I thought I might find the subjects and sure enough there they were, grotesque denizens of the dark world, ominously hanging around the entrances of holes in the sheer walls waiting for their supper to arrive in the form of unsuspecting insects.  Unfortunately the ground where I would have to stand and set up the tripod was alive with swarming masses of Army Ants.  So my dilemma was to suffer the painful bites of a myriad enraged ronchadores or come back on another night.  I decided on the latter.

Gladiator Frog

While walking past the pond on my way back to the restaurant I could hear several male Gladiator Frogs calling.  I didn’t want to go back with no results for my efforts so decided to go and take a look.  As luck would have, there was one male sitting on a palm leaf stem at eye level 6 feet off the ground, (my eye level).  It duly obliged by posing perfectly for its profile.  So even if the shot you want is not always available, there is always something else you can get if you look.

Text and Photographs are taken from the forthcoming book:

The Natural History of Bosque del Cabo by Philip Davison

Temperature and Rainfall

Average Daily Rainfall 0.14 ins.  Total Weekly Rainfall 1.00 ins

Average Daily Rainfall 1.0 mm.  Total Weekly Rainfall 7.1 mm

Highest Daily Temp 89°F.  Lowest Daily Temp 74°F.

Highest Daily Temp 31.4°C.  Lowest Daily Temp 23.4°C.

Species List for the Week

Mammals

  • Howler Monkey
  • Spider Monkey
  • White-faced Monkey
  • Kinkajou
  • White-nosed Coati
  • Agouti
  • Alfaro’s Pygmy Squirrel
  • Nine-banded Armadillo

Birds

  • Red-lored Amazons
  • Scarlet Macaws
  • Grey-necked Woodrail
  • Great Curassow
  • Roadside Hawk
  • Pale-billed Woodpecker
  • Chestnut-backed Antbird
  • Black-hooded Antshrike
  • Common Paureque
  • Short-billed Pigeon
  • Magnificent Frigatebird
  • Long-billed Hermit
  • Rufous-tailed Hummingbird
  • Blue-crowned Manakin
  • Red-capped Manakin
  • Fiery-billed Aracari
  • Chestnut-mandibled Toucan
  • Blue Dacnis
  • Cherrie’s Tanager
  • Golden-hooded Tanager
  • Red-legged Honeycreeper
  • Wedge-billed Woodcreeper
  • Great Kiskadee
  • Tropical King Bird
  • Masked Tityra
  • Black-throated Trogon
  • Great Tinamou
  • House Wren
  • Riverside Wren
  • Yellow-throated Euphonia
  • Black Vulture
  • Turkey Vulture

Reptiles

  • Basilisk
  • Boa Constrictor
  • Central American Smooth Gecko
  • Clawless Gecko
  • Five-lined Ameiva
  • Golfo Dulce Anole
  • Mediterranean House Gecko
  • Northern Cat-eyed Snake
  • Pug-nosed Anole
  • Salmon-bellied Racer
  • Tiger Rat Snake
  • Tropical Bird-eating Snake

Amphibians

  • Banana Frog
  • Black and Green Poison Arrow Frog
  • Golfo Dulce Poison Arrow Frog
  • Marine Toad
  • Olive Tree Frog
  • Parachuting Red-eyed Green Tree Frog
  • Red-eyed Green Tree Frog
  • Smoky Jungle Frog
  • Tink Frog

Butterflies

  • Anartia Fatima
  • Anartia jatrophae
  • Archaeoprepona demophon
  • Caligo eurilochus
  • Colobura dirce
  • Dryas iulia
  • Eurema daira
  • Euptoieta hegesia
  • Euselasia
  • Eurybia lysisca
  • Glutophrissa Drusilla
  • Heliconius erato
  • Heliconius hecale
  • Heliconius ismenius
  • Heliconius sapho
  • Heraclides cresphontes
  • Hermeuptychia hermes
  • Morpho helenor
  • Morpho menelaus
  • Opsiphanes tamarindi
  • Parides erithalion
  • Philaethria dido
  • Phoebis argante
  • Phoebis sennae
  • Pyrgus oileus
  • Saliana longirostris
  • Siproeta stelenes
  • Staphylus mazans
  • Strymon megarus
  • Urbanus simplicius

 Plants

  • Alamandra  cathartica Flowering
  • Alpinia purpurata Flowering
  • Anthurium salvinii Flowering
  • Apeiba tibourbou Flowering
  • Arachis pintoi Flowering
  • Arundina graminifolia Flowering
  • Aspidosperma spruceanum Fruiting
  • Astrocaryum standelyarum Fruiting
  • Atrocarpus heterophyllus Fruiting
  • Averrhoa carambola Fruiting
  • Brownea macrophylla Flowering
  • Cascabella thevetia Flowering
  • Chamaedorea costaricana Fruiting
  • Cocos nucifera Flowering and Fruiting
  • Crestentia alata flowering and Fruiting
  • Costus speciosus Flowering
  • Couroupita guianensis Flowering and Fruiting
  • Dipsis lutescens Fruiting
  • Ficus citrifolia Fruiting
  • Ficus insipida Fruiting
  • Gustavia brachycarpa Flowering
  • Hedychium coronarium Flowering
  • Heliconia chartacea Flowering
  • Heliconia latispatha Flowering
  • Heliconia pogonantha Flowering
  • Heliconia psittacorum Flowering
  • Heliconia rostrata Flowering
  • Hibiscus rosa-sinensis Flowering
  • Hymenaea coubaril Fruiting
  • Ixora coccinea Flowering
  • Lacistema aggregatum Fruiting
  • Lacmellea panamensis Flowering and Fruiting
  • Lantana camara Flowering and Flowering
  • Lagerstroemia speciosa Flowering and Fruiting
  • Mangifera indica Fruiting
  • Miconia argentia Flowering
  • Morinda citrifolia Fruiting
  • Musa acuminate Flowering and Fruiting
  • Naucleopsis uliae Fruiting
  • Pandanus tectonus Fruiting
  • Piper auritum Flowering and Fruiting
  • Piper umbellatum Flowering and Fruiting
  • Pleiostachya pruinosa Flowering
  • Psidium guajava Flowering and Fruiting
  • Stachytapheta frantzii Flowering
  • Terminalia catappa Flowering
  • Tocoyena pittieri Flowering and Fruiting
  • Virola koschnyi Fruiting
  • Vochysia ferruginea Fruiting

 

 

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