Archive for the ‘Red-eyed Green Tree Frog’ Tag

Mysteries of the Natural World   Leave a comment


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

Frog Chorus

The week has been dry and sunny but with the clouds progressively becoming a more frequent feature.  Increasingly the skies are becoming overcast and the azure blue of the dry season has been replaced by a blanket of grey.  The sun manages to peep through for a while but then is lost once more behind an obscuring haze, only the faint outline of its orange disc visible to the naked eye.

The amphibian population is gathered and ready for the real rains to begin.  There are more male frogs setting up territories at each location around the pond.  The Savage’s Thin-fingered frog and the Marine Toads prefer the pond edge.  The Banana Frogs and the Small-headed Frogs situate themselves on the vegetation floating on the water.  A little higher up the Milky Frogs have taken up their positions on the upper surfaces of the leaves overhanging the water.  Finally the Red-eyed Green Tree Frogs can be heard calling from nearer the tops of the vegetation.  When the rains do arrive, with the typical early May deluges, the activity around the pond will increase exponentially.  More species will arrive, particularly the ones that reproduce directly in the water.  It is just a matter of time.

Red-eyed Green Tree Frog. Hylidae. Phyllomedusinae.

Red-eyed Green Tree Frog, (Agalychnis callidryas). Male. Calling.

Skipping Over Marked Metal

Butterflies exhibit a variety of dimorphisms.  They may be sexually dimorphic, strongly or otherwise, males and females may look like completely different species. They maybe seasonally dimorphic, wet season forms differing from dry season forms.  They may be geographically polymorphic with one species varying in size, color and markings over a wide geographical range to the point where you would once again think you were looking at totally different species.

One of the more commonly seen riodinids, or metalmark butterflies, in the forests of Bosque del Cabo is Metacharis victrix.  I regularly see the fiery orange females but not so often the males which are much more of a deep brick red.  They have the frustrating habit of perching on the underside of leaves so to capture the image you have to get on the ground, lie on your back and point the camera upwards.

Metacharis victrix. Riodinidae. Riodininae

Metacharis victrix. Male.

They are frequently found in bright understory light gaps.  The larval food plant is any one of the Heisteria species of which, Heisteria accuminata, is very abundant in this area.

Heisteria accuminata. Olacacea

Heisteria accuminata. Fruit

The skippers are a difficult family of butterflies to identify too.  A great many of them are very small, sometimes no bigger than an adult human fingernail.  To add to the problem of identity, there are so many of them and they quite often they are muted shades of brown.  It does take a certain level of expertise to identify them to species level.

Last week I had one land close to me and fortunately stay still.  Skippers are prone to taking flight at the slightest disturbance and are also averse to the camera flash going off.  This individual was the Perching Saliana (Saliana esperi).  The earthy brown of the hindwing underside has a contrasting creamy flash.  There are two pale windows in the dark half of the wing.

Perching Saliana. Hesperiidae. Hesperiinae.

Perching Saliana, (Saliana esperi)

It’s a Mystery

As much as I would love to study moths as well as butterflies, time does not allow this luxury.   There are up 14,000 species of butterfly and moth in Costa Rica, the majority being moths.  Many of the moths we have no idea of their life histories.  So when a moth does turn up that I can take a photograph of, if I cannot arrive at an identity then I do not fret over the fact, I just enjoy it for what it is, a beautiful thing to behold.

Unidentified Moth. Philip Davison.

Unidentified Moth

Actually that holds true for many insects.  Costa Rica has an estimated 365,000 named species of insects within its territory, that is 1,000 species for every day of the year, which would require exceptional identification skills.  Identity to species level is best left in the hands of those who specialize in a particular group.  I found a stinkbug sitting on a leaf that made a wonderful subject but I have not been able to name it to species level.

Stinkbug. Hemiptera. Heteroptera.

Unidentified Stinkbug

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

A New Season of Discovery   10 comments


Philip Davison. nature diaries. Osa Peninsula. Costa Rica.

After a five week period away from the Osa Peninsula I am back to carry out another year of research.  For the past sixteen years I have been monitoring populations of both butterflies and amphibians in the forests of Cabo Matapalo on the tip of the Osa Peninsula in South West Costa Rica.  I collect the daily weather data and compare changes in amphibian populations against precipitation and butterflies populations against temperature in an effort to evaluate how or whether climate change effects the fauna of a tropical rain forest.

Marine Toad. Amphibians. Osa Peninsula. Costa Rica.

Marine Toad, (Chaunus marinus)

As I live in the forest and can be found constantly walking the trail systems, camera in hand, it provides ample opportunity to photograph the diversity of life that surrounds me.  I am generally photographically prepared for small things so unless I am going out specifically to capture images of mammals or birds then my photographic galleries generally consist of reptiles, amphibians, all manner of arthropods as well as any plant and fungi features that catch my eye.

Savage's Thin-fingered Frog. Frogs

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

This blog acts as an expanded form of my nature diaries which are simply daily recordings on Excel spreadsheets.  I enjoy sharing my experiences with those who read my blog and over the years the number of subscribers constantly increases.  If you are a first-time reader, then welcome and I hope you enjoy the content and the photos.  I am not a professional photographer but I do try and take the best composed shots I can.

Banana Frog. Wet Season.

Banana Frog, (Dendropsophus ebreccatus)

The blog also allows visitors to the area an insight of what they might expect to see in their absence or when they arrive as well as providing a small amount of information about the natural history of the organisms I feature.  I try to post one blog a week but sometimes time constraints means there may be occasions when this is not possible.

Small-headed Frog. Pond life.

Small-headed Frog, (Dendropsophus micracephalus

For me the year does not begin on the January 1st but rather on my return to the area in November.  At this time of year we should be moving out of the main rainy season, which is what caused me to leave for a month or so, and into the dry season.  There is no exact date and sometimes the rains hang on until December while other times the sun has started to shine constantly by mid-November.  Anyway, here we go with the opening blog of the 20016/17 season.

Olive-snouted Treefrog. Philip Davison

Olive-snouted Treefrog, (Scinax elaeochrous)

First things first.  November normally heralds the ending of the rainy season.  Sometimes the wet period may continue into December but by now we are looking towards a drying of the forest.  Not so this year.  This has been, without doubt, the wettest November I have recorded in 17 years, 185 inches of rain fell in that 30-day period.  The area was briefly closed down as bridges were not crossable, roads were not passable and the local town of Puerto Jimenez and its attendant landing strip were closed due to being under water.  This may bode well for the coming dry season when for 4/5 months the area receives little or no rain whatsoever but at the moment the forest floors have rivulets with running water everywhere.

Red-eyed Green Tree Frog. Costa Rica

Red-eyed Green Tree Frog, (Agalychnis callidryas)

The daily torrential downpour has made wildlife spotting rather difficult.  It is neither easy to see or hear anything in those conditions.  In the inter deluge periods I have been out searching for whatever I could find and it may come as no surprise that the amphibians most certainly have enjoyed the excess water.  All the usual members of the pond community have been out calling; Banana Frogs, Small-headed Frogs, Red-eyed Green Tree Frogs, Parachuting Red-eyed Green Tree Frogs, Savage’s Thin-fingered Frog, Marine Toads and Masked Smiliscas.  Even the largest tree frogs in Costa Rica, the Milky Frogs have been coming out, which is unusual this time of year.  Away from the pond the Tink Frogs and Fitzinger’s Rain Frogs call as soon as the sun sets.  Here are some photographs of the amphibians you may be lucky enough to see if you visit the Osa Peninsula now.

Parachuting Red-eyed Green Tree Frog. Torrential Rain.

Parachuting Red-eyed Green Tree Frog (Agalychnis spurrelli)

Tink Frog. Frog chorus.

Tink Frog, (Diasporus diastema)

Gladiator Frog. Mud puddle nest

Gladiator Frog, (Hypsiboas rosenbergi).

Bolivian Frog. Foam nest.

Bolivian Frog, (Leptodactylus bolivianus)

Masked Tree Frog.

Masked Smilisca, (Smilisca phaeota)

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

The Trees Have Eyes   2 comments


Felipe del Bosque Blog August 5th 2013

title copy

Don’t Be Fooled

This week has been something of a mixed bag as far as the weather goes.  We are well into the wet season now and as might be expected it has been raining a lot.  The earlier part of the week was quite pleasant with clear skies, bright sunny days and star filled cloudless skies at night.  It seemed as if we had entered that period known locally as the veranillo or little summer.  At this time of year there is a two week period where the rain stops and it dries up.  It is nice time to visit the Pacific coast of Costa Rica as there are not so many visitors as in the main holiday periods, the weather is conducive to exploration and all the vegetation is lush and green.  If this was the veranillo then it was short-lived because the rain came back.  The latter part of the week has experienced the normal weather pattern for this time of year with days overcast and the rain starting early evening then continuing through the night into the early morning.   Those are perfect conditions for wildlife watching and photography, not too hot to go out and no bright contrasting shadows.

Further into the week the rain became more persistent.  Sometimes it rained all day but with no more than a gentle drizzle followed by more heavy precipitation overnight.  Each day is different.  Some days the sun shines, some it doesn’t but whatever the weather, this is a rainforest, everything is adapted to living in constantly rainy conditions and so at least some wildlife of one sort or another should be guaranteed.

The latter part of the week dispelled the notion that we might still be in the veranillo.  There have been some violent thunderstorms producing spectacular light shows in the sky accompanied with a moderate amount of rain.  The good news is that the creeks are running with a substantial flow rate now after a period of being very dry.

Caught In The Act

It has been another eventful week as far as animal sightings go.  On several separate occasions a Puma, (Puma concolor), and Ocelot, (Leopardus pardalis), have been recorded by the trail cameras that have been set up on the Titi Trail.  This is a trail running through secondary growth.  When the ground is wet, which it tends to be for 7 months of the year, you can see quite readily the tracks of any passing animals.  Most tracks are distinctive enough to allow identification of the creature leaving them.

One day tracks from huge male Puma were found on the approach to the suspension bridge.  The cat then appears to have walked over the bridge as the tracks were readily visible in the mud straight off the lodge side of the bridge and were heading in the direction of the restaurant.  The Spider Monkeys, (Ateles geoffroyi), were most certainly aware of the predators presence as they gave off their loud and distinctive alarm call for a long time.  The tracks then left the main trail and headed off through the forest to the lookout point over the Gulf.  Finally they turned and headed down the Creek Trail to the platform of the zip-line and disappeared into the forest.  We know that the female Puma is around so this may have been a transient male searching for a mate.

Puma Print

Bosque has recently started a project whereby the animals can be seen and photographed without anyone needing to be present.  We have set up 2 trail cameras near both the entrance and exit to the Titi Trail.  The cameras have been placed looking down the trail so that if anything is either walking towards or away from the camera we should get a good 30 seconds of footage.  The cameras are motion sensitive and detect infra red.  They use passive infra red LEDs to illuminate the subject without producing any visible light or flash.

Over the past month the cameras have produced some very good photos and video of what is around and also when it is around and what it is doing.  The surprising discovery is just how often the Collared Peccaries, (Tayassu tajacu), are walking the trails.  There seem to be large herds that come back and forth.  It would appear at first that they don’t have a large territory but it may well be there are several distinct herds and unless they are somehow marked in a fashion that would allow their identity to be easy verified then we shall just have to enjoy the sight of them walking by.

One of the cameras has a resident Agouti, (Dasyprocta punctata), that seems to come out and mark the trail every hour so we can expect to get to see an endless number of videos featuring that particular individual.  But he could be living a charmed existence.  We have viewed several videos featuring Ocelots, both day and night, and we know there is a female Puma in the area, she just hasn’t been captured on our cameras yet.  She has, however, featured in a cameo role on a trail camera put up not too far from our own by a young boy from England who was staying at the lodge last weekend.

There have been a number of other animals passing by in greater or lesser numbers: White-nosed Coatis, (Nassua narica), White-lipped Peccary, (Tayassu pecari), Tamanduas, (Tamandua mexicana), Nine-banded Armadillos, (Dasypus novemcinctus), Red-tailed Squirrels, (Sciurus granatensis), Tayras, (Eira barbara), Pacas, (Agouti paca), Common Opossum, (Didelphis marsupialis), Striped Hog-nosed Skunk, (Conepatus semistriatus),  Great  Curassow, (Crax rubra), Great Tinamou, (Tinamus major).  But let’s not forget that this is just the activity on the ground in the vicinity of the cameras, there is also a whole load of other activity going on up and above this level in the trees.

M2E38L130-130R407B315         M2E27L54-54R392B294         M2E28L68-68R393B303

M2E1L0-0R350B300         M2E45L47-47R350B300         M2E45L32-32R350B300

M2E45L32-32R350B300         M2E26L49-49R389B305         M2E1L0-0R350B300

Quadruple Vision

It doesn’t take long once the sun has set to go out and find a great many creatures that have been hiding during the day.  My nightly excursions to the pond this week have been rewarded with sightings of Northern Raccoons, (Procyon lotor), Common Opossums and Nine-banded Armadillos.  While looking at these nocturnal mammals your flashlight may catch the diamond sparkles being reflected from the grass, from the plants, from the tree trunks, everywhere in fact.  Follow the sparkles in and you will be amazed to find it is your light being reflected back at you from the eyes of spiders.  Not only might that revelation be somewhat astounding but also the size of the spiders themselves which may be tiny.  Depending upon the angle at which you catch it, the eyeshine may be silver, blue, green or orange but with the spiders always a sparkle.

Have a care though because not all of the spiders are tiny.  Once the sun sets below the horizon, emerging from safe daytime refuges come the Wandering Spiders, (Cupiennius spp) to set up their positions on the leaf tops or stems.  The Wandering Spiders don’t build webs, they are ambush predators.  They sit and wait.  The legs are covered  in hairs of differing types each of which performs a specific function.  There are tactile hairs which are stiff and are sensitive to touch.  A similar hair, the trichobothrium is super sensitive to the slightest touch as well as eddies in air currents.  There are chemosensory hairs that detect changes is the molecular environment around them.  There are slit-like structures called sensillae near the joints of the legs.  These detect vibration and mechanical movement of the substrate.

Cupiennius_sp

Even though the spider has eight eyes they are not necessarily used for hunting but all that other highly receptive sensory apparatus ensures the spider knows whether there is predator or prey close by.  If it is the latter then it is generally goodbye.  I have seen the Wandering Spiders jump and take moths from the air, I have seen then jump on any small passing invertebrate and I have even seen then eating the Red-eyed Green Tree Frogs, (Agalychnis callidryas), at the pond.

Wandering Spiders are not dangerous, they will not kill you but they will give a nasty little ulcerated bite.  And they can jump so don’t get too close.  But if you leave them alone they won’t bother you.

Small Head and bulging Red Eyes.

The rains always bring out the frogs.  June, July and August is the best time to see frogs at Bosque as it is the main breeding season for many of the species to be found on the grounds.  Year by year there is a flux not only in the species to be found but also in the numbers of those species.  The Red-eyed Green Tree Frogs are present all year, every year but in much greater numbers in the wet season when their distinctive “chuck chuck” calls can be heard everywhere around the pond.  Their egg masses can be seen throughout the year too hanging as they do from the underside of leaves overhanging the water where the diligent female has placed them.

Over the past week there have been male Red-eyed Green Tree Frogs calling from every level of vegetation immediately next to or in the close vicinity of the pond.  The males set up their territories once the sun has set and then call to attract a mate.  The female which is much bigger than the male selects a partner for the evening depending on the quality of his call, the deeper the better.  The frogs pair up and visit the pond about 3 times over the course of the evening.  Each time the female absorbs a lot of water through her skin, fills her bladder and then they amplected couple make their way to a leaf overhanging the water.  The female lays a group of about fifty eggs which the male sitting on her back fertilizes as she expels them.

Agalychnis_callidryas

The eggs hang over the water for about a week until the tadpoles have developed enough to wriggle free and drop into the water where they have to complete the aquatic stage before metamorphose into froglets which leave the water and disappear into the vegetation before emerging some time later as adults.

The Small-headed Frog, (Dendropsophus microcephala), on the other hand may or may not be present each year.  Sometimes there are just one or two calling over the course of a season, last year there were none.  This year on the other hand they have arrived in huge numbers.  I was never sure in the years gone by whether they were being outcompeted by the more commonly seen and heard Banana Frog, (Dendropsophus ebraccatus), which are always here in reasonably large numbers.  This year though they haven’t appeared in such profusion as in years past.  I think it is time to start the frog counts again.

Dendropsophus_microcephalus

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 

Try Again

Several months ago there was a White-necked Jacobin Hummingbird, (Florisuga mellivora), that had nested right by the path on the Zapatero Trail.  The nest contained 2 eggs but one day both the eggs had disappeared and despite the fact the nest was intact the female was nowhere to be seen.  Then, a couple of weeks ago on a different part of the Zapatero Trail, there appeared another nest looking exactly the same and of the same species.  Although the two nest sites seemed somewhat removed, when looking at the map, the trail curves round at 180º so the second nest in actual fact lay very close to but just uphill of the first.  My guess would be that it is the same female.  She might have chosen a different location but not too far away based on the failure of the prior brood.

Florisuga_mellivora

Every day as I walked the Zapatero Trail the female White-necked Jacobin would sit tight until I approached to passing.  She would then take off and wait for me to go further down the trail before returning to the nest.  As the chick grew progressively larger the female would spend less time on the nest.  The chick now filled the nest and one day as I got closer I could see the nest was empty so I hope on this occasion the chick had managed to take to the air and fly off.

Florisuga_mellivora

There is a low success rate for breeding birds.  The forest is full of predators and parasites.  Certainly around the lodge if there is a nest containing either eggs or chicks it doesn’t take long for an individual of the species Tropical Bird-eating Snake, (Pseustes poecilonotus), to pay visit.  These snakes can reach well over 6 feet in length so can eat birds of most sizes here.  Quite often the birds have to raise 2 or 3 clutches a year to have 1 successful set of fledglings.

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 0.67 ins.  Total Weekly Rainfall 4.70 ins

Average Daily Rainfall 16.8 mm.  Total Weekly Rainfall 117.9 mm

Highest Daily Temp 84°F.  Lowest Daily Temp 74°F.

Highest Daily Temp 28.8°C.  Lowest Daily Temp 23.3°C.

Species List for the Week

Mammals

  • Mantled Howler Monkey
  • Spider Monkey
  • White-faced Capuchin Monkey
  • Nine-banded Armadillo
  • Common Opossum
  • Common Tent-making Bat
  • Western Red Bat
  • Northern Raccoon
  • White-nosed Coati
  • Agouti
  • Red-tailed Squirrel
  • Collared Peccary

Birds

  • Mealy Amazon
  • Orange-chinned Parakeet
  • Red-lored Amazon
  • Scarlet Macaw
  • Great Curassow
  • Laughing Falcon
  • Pale-billed Woodpecker
  • Black-hooded Antshrike
  • Chestnut-backed Antbird
  • Short-billed Pigeon
  • Red-capped Manakin
  • Chestnut-mandibled Toucan
  • Golden-crowned Spadebill
  • Great Tinamou
  • Little Tinamou
  • Black-throated Trogon
  • Black Vulture
  • Turkey Vulture

Reptiles

  • Barred Ameiva
  • Cat-eyed Snake
  • Central American Smooth Gecko
  • Central American Whiptail
  • Common Anolis
  • Common Basilisk
  • Clawless Gecko
  • Four-lined Ameiva
  • Golfo Dulce Anolis
  • Green Iguana
  • Litter Skink
  • Mediterranean House Gecko

Amphibians

  • Banana Frog
  • Black and Green Poison Arrow Frog
  • Fitzinger’s Rain Frog
  • Golfo Dulce Poison Arrow Frog
  • Marine Toad
  • Milky Frog
  • Parachuting Red-eyed Green Tree Frog
  • Red-eyed Green Tree Frog
  • Rough-skinned Dirt Frog
  • Savage’s Thin-fingered Frog
  • Small-headed Frog
  • Tink Frog

Butterflies 

  • Anartia Fatima
  • Anartia jatrophae
  • Colobura dirce
  • Dryas iulia
  • Heliconius erato
  • Heliconius ismenius
  • Heliconius sapho
  • Hermeuptychia hermes
  • Mesosemia zonalis
  • Morpho cypris
  • Morpho menelaus
  • Philaethria dido
  • Phoebis sennae
  • Pierella luna

Plants

  • Alamandra  cathartica Flowering
  • Alpinia purpurata Flowering
  • Apeiba tibourbou Fruiting
  • Arachis pintoi Flowering
  • Arundina graminifolia Flowering
  • Attalea rostrata Fruiting
  • Bauhinia variegata Flowering
  • Cascabella thevetia Flowering and Fruiting
  • Citrus spp  Fruiting
  • Clusia vallerii Fruiting
  • Cocos nucifera Flowering and Fruiting
  • Crestentia alata flowering and Fruiting
  • Costus speciosus Flowering
  • Dypsis lutescens Flowering and Fruiting
  • Etlingera elatior Flowering
  • Ficus insipida Fruiting
  • 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
  • Pachira quinata Flowering
  • Piper auritum Flowering and Fruiting
  • Piper nigrum Fruiting
  • Piper umbellatum Flowering and Fruiting
  • Pleiostachya pruinosa Flowering
  • Plumeria rubra Flowering
  • Stachytarpheta frantzii Flowering
  • Zammia sp Flowering

 

 

Here We Go Again   4 comments


Felipe del Bosque Blog November 12th 2012

Sun Shade

I made an earlier than normal return to Bosque this year.  The wet season had seen its share of rain but now the heavy showers are interspersed with long periods of blue sky and bright sun.  Mammal, bird, reptile, amphibian and butterfly sightings are good.

I keep a daily nature diary of animals and plants, (flowering and fruiting), that I have seen at the lodge.  At the end of the week the lists are added to the bottom of this blog which allows people to see what is going on in advance of their visit to Bosque or to keep in touch when they have left.  Anyone reading but not visiting can gauge the amount of activity taking place in the natural world down on the tip of the Osa Peninsula, Costa Rica.

This year I have decided to add something extra, something a little different.  Birders have their “Big Year” so I thought it might be nice to have a big year but not limiting myself to the avifauna, but rather everything.  It won’t take much more effort over and above what I already record and catalogue.  It is not competitive either, just a bit of fun.  It will enable me to post a weekly update of cumulative numbers across the board of species inventories.  The readers will then be able to see at a glance the amount of fauna and flora that can be experienced and over what period of time at Bosque.

The records will be confined to the 800 acres that constitute the grounds of Bosque del Cabo and will be based on casual observations.  Hopefully I should get some photos to post too.

Doing the Rounds

Around the grounds there are the usual mammal sightings with Agoutis, (Dasyprocta punctata), White-nosed Coatis, (Nasua narica), and Red-tailed Squirrels, (Sciurus granatensis), in the gardened areas in front of the restaurant.  Spider Monkeys, (Ateles geoffroyi), Howler Monkeys, (Allouata palliata), and White-faced Monkeys, (Cebus capucinus), can be seen just about everywhere around the grounds.  The White-faced Monkeys have been up to their usual nasty tricks.  One couple out in the garden was trying to photograph a Chestnut-mandibled Toucan, (Ramphastos swainsoni), when a White-faced Monkey grabbed and dispatched the unfortunate bird.  It wasn’t the photograph they were looking for but it makes for a talking point back home.

One night, just before dinner, a Kinkajou, (Poto flavus), came into the bar, which was full of guests at the time, and made its way up one of the support poles into the roof and disappeared from view.  Kinkajous are not uncommon around the grounds of Bosque and can quite often be heard up in the tree tops at night but this was the first sighting in the bar.

Summer Calling

The Scarlet Macaws can be seen in the morning flying east to the Golfo Dulce beaches where they take up their daily occupancy of the almond trees, the nuts forming a staple part of their diet.  Later in the afternoon they can be flying this time west returning to roost for the evening.  Their strict adherence to a timetable allows guests to position their cameras to frame the sea and the sky then just wait for the macaws to fly by and fill the foreground space between.

I thought I might make it back before the migrant birds returned but they got here before me.  The very distinctive call of the Summer Tanger, (Pingara rubra) can be heard from the vegetation all around the lodge and will continue to be so for the next few months.  The Dusky-capped Flycatcher, (Myriarchus tubiculifer), is another bird with a soft yet unmistakable call which is being heard all around the restaurant area and mango orchard at the minute.

Prior to their visit, bird calls are something that a visitor to the tropics should acquaint themselves with as not only will they allow you to hear what is around, but also where it is which is essential if you want to spot them.  Looking for birds within the depth of the forest is a somewhat difficult task due to the obstructive presence of so much vegetation.  The open areas, gardens and forest edges are your best bet for seeing much of the bird life.

At the moment within the darker confines of the forest beneath the canopy the Red-capped Manakin, (Pipra mentalis), and the Blue-crowned Manakin, (Pipra coronata), are calling as well as the Rufus Piha the call of which sounds like someone giving a wolf whistle.

In front of the restaurant the Roadside Hawk ,(Buteo magnirostris), Crested Caracaras, (Caracara cheriway), and Yellow-headed Caracaras, (Milvago chimachima), are a daily sight along with the ever present Black Vultures and Turkey Vultures.

Spotted Frogs

Agalychnis callidryas

Despite the fact that it is still wet, the Tink Frogs, (Diasporus diastema), have now all but stopped calling.  Down by the pond the Red-eyed Green Tree Frogs, (Agalychnis callidryas), are still present along with the Marine Toads, (Rhinella marinus) and Savage’s Thin-fingered Frog, (Leptodactylus savegei).  There are one or two Banana Frogs, (Dendropsophus ebrecattus), sitting on the Water Hyacinths, (Eichhornia crassipes), and the occasional call of a Parachuting Red-eyed Green Tree Frog, (Agalychnis spurelli), can be heard.  The Gladiator Frogs, (Hypsoboas rosenbergi), that were out in profusion a few months ago have disappeared.  There have been one or two Masked Smiliscas, (Smilisca phaeota), calling too and as the sun sets you can hear the distinctive “Chuck” of Fitzinger’s Rain Frog, (Craugastor fitzingeri).

Leptodactylus savagei

The Red-eyed Green Tree Frogs are still spawning and their eggs can be found in distinctive gelatinous clusters hanging beneath the leaves overhanging the pond which make an easily available food source for the Cat-eyed Snakes, (Leptodeira septentrionalis).  Once the sun sets out come the snakes.  They make their way over the surface of the pond and over the vegetation behind, tongues flicking in and out in search of that protein packed jelly.  One night I found a Terciopelo sitting above head height on a leaf behind the pond.  The occasional sleeping Basilisk, (Basaliscus basaliscus), may also be encountered but they are easily disturbed.  You make get a shot but it doesn’t take much to cause them to fall to the ground and run for cover.  While out at night you cannot fail to see, especially if looking for eyeshine, the tell tale diamond sparkle coming from the eyes of Wandering Spiders, (Cupiennius sp) sitting on top of the leaves.  One night I had fun taking some pictures of a tiny katydid down by the Bosque pond.  I have no idea what species it is but it was quite photogenic.

Agalychnis callidryas eggs

Fitzinger's Rain Frog

Smilisca phaeota

Wandering Spider

Unidentified Katydid

Only When The Sun Shines

As the weather is reasonably dry and bright, at least on some days, the butterflies take to the wing.  There are neither a huge number of species nor many individuals of each species to be seen this time of year. If you do go for a walk on a sunny day you should get to see some of the more brightly colored species around the grounds, particularly at the Lantana bush where several species of Longwings will be flitting from flower to flower in search of nectar. The earlier you go the better it is to get the photographs before they are fully warmed up and less likely to settle for any great period of time.

Dryas iulia         Heliconius ismenius         Heliconius erato

The same applies to the pond and the dragonflies.  There are very few species around at the moment.  But if you watch them, observing where they land, then you can set up your camera and wait.  With a little patience you should get a fairly good chance of a close-up shot.

Micrathyria ocellata         Micrathyria ocellata        

Fruitless Search

The end of the wet season is not the best time to find either flowers or fruit.  The rain will have ensured that the forests have a deep verdant green aspect to them.  But as we move into that transitional period from wet to dry, many of the plants are stimulated into bearing flowers.  By the time we get into December and January there will be a greater, sometimes subtle and at other times garish, display of color throughout the forest.  For now though you just have to enjoy the deep greens.  If you thought green was green you were very much mistaken.  Find a vantage point and look out over the forest.  You will see emerald, jade, olives, lime, bottle green, sea greens, pea green in fact green in every shade and hue you could imagine.

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

 A Small Problem

One of the most compelling sites of the rainforest is ubiquitous presence of the industrious Leaf-cutter Ants, (Atta sp) which seemingly never rest.  When they are not active their trails can be seen as clear cut paths that run through lawns and across the forest floor.  When they are active, the trails resemble rivers of green moving leaf fragments, which the majority of the workers heading back towards the nest are carrying in their mandibles above their bodies.

Atta cephalotes         Atta cephalotes         Atta cephalotes

Once the leaf is taken into the nest it is dropped and then the work of another caste begins.  It chops the leaf into smaller fragments.  Descending down into the depths of the nest the workers get smaller and smaller progressively cutting the leaf into ever finer fragments which by the time they reach the nest gardens are processed into a grey chewed up mulch.  The ants defecate on this which adds amino acids and enzymes.  This is now the compost on which they grow a very specific fungus that ultimately provides food and sustenance for all the ants in the colony, (upto 8 million of which exist in a mature colony).

Atta cephalotes

This last week there has been a tremendous amount of leaf-cutter activity on all of the Bosque trails and also by my cabin.  Here was a perfect opportunity to try and get some pictures.  This is never an easy task.   You have to get the camera in a position where you can see the ants passing through a plane of view.  Due to the close proximity of the lens to the subject when an ant does pass by it does so very quickly so the shutter speed has to be high.  The distance from the lens means you have a shallow field of view, so to increase your chances of getting one or two in the right plane; you have to close the aperture right down.  A fast shutter speed and a minute aperture allow very little natural light to enter so you have to provide a lot of light by way of flash.  I use 5 separate flash units.  Even then, the chances of getting one at the right exposure filing the frame are slim, most of the ants are entering or exiting the frame or are too far away or are too close.  But due to the number of them all moving in the same direction, then you should get one or two keepers, it depends on how much time and patience you have.

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 0.23 ins.  Total Weekly Rainfall 1.63 ins

Average Daily Rainfall 5.9 mm.  Total Weekly Rainfall 41.4 mm

Highest Daily Temp 91°F.  Lowest Daily Temp 75°F.

Highest Daily Temp 32.5°C.  Lowest Daily Temp 23.9°C.

Species List for the Week

Mammals

  • Howler Monkey
  • Spider Monkey
  • White-faced Monkey
  • Nine-banded Armadillo
  • White-nosed Coati
  • Agouti
  • Red-tailed Squirrel
  • Vesper Rat

Birds

  • Mealy Amazon
  • Red-lored Amazon
  • Scarlet Macaws
  • Great Curassow
  • Crested Caracara
  • Laughing Falcon
  • Roadside Hawk
  • Yellow-headed Caracara
  • Pale-billed Woodpecker
  • Belted Kingfisher
  • Dusky-capped Flycatcher
  • Chestnut-backed Antbird
  • Black-hooded Antshrike
  • Rufus Piha
  • Short-billed Pigeon
  • White-tipped Dove
  • Rufus-tailed Hummingbird
  • Stripe-throated Hermit
  • Blue-crowned Manakin
  • Red-capped Manakin
  • Chestnut-mandibled Toucan
  • Grey-headed Tanager
  • Summer Tanager
  • Tawney-winged Woodcreeper
  • Golden-crowned Spadebill
  • Great Kiskadee
  • Black Vulture
  • Turkey Vulture

Reptiles

  • Cat-eyed Snake
  • Clawless Gecko
  • Common Basilisk
  • Four-lined Ameiva
  • Golfo Dulce Anolis
  • Green Iguana
  • Litter Skink
  • Terciopelo

 Amphibians

  • Banana Frog
  • Black and Green Poison Arrow Frog
  • Fitzinger’s Rain Frog
  • Marine Toad
  • Masked Smilisca
  • Parachuting Red-eyed Green Tree Frog
  • Red-eyed Green Tree Frog
  • Smoky Jungle Frog
  • Stejneger’s Dirt Frog

Butterflies

  • Anartia Fatima
  • Anartia jatrophae
  • Dryas iulia
  • Eurybia lycisca
  • Glutophrissa Drusilla
  • Heliconius erato
  • Heliconius hecale
  • Heliconius ismenius
  • Heliconius sapho
  • Hermeuptychia hermes
  • Heraclides cresphontes
  • Magneuptychia libye
  • Morpho helenor
  • Morpho Menelaus
  • Opsiphanes tamarindi
  • Pareuptychia ocirrhoe
  • Philaethria dido
  • Pierella helvina
  • Pierella luna
  • Pyrgus oileus
  • Pyrrhogyra crameri
  • Taygetis Andromeda
  • Urbanus simplicius

 Plants

  • Alamandra  cathartica Flowering
  • Alpinia purpurata Flowering
  • Apeiba tibourbou Flowering
  • Arachis pintoi Flowering
  • Arundina graminifolia Flowering
  • Bauhinia variegata Flowering
  • Cananga odorata Flowering and Fruiting
  • Cascabella thevetia Flowering
  • Citrus spp  Fruiting
  • Clusia rosea Flowering andFruiting
  • Clusia vallerii Flowering and Fruiting
  • Cocos nucifera Flowering andFruiting
  • Crestentia alata flowering and Fruiting
  • Costus speciosus Flowering
  • Couroupita guianensis Fruiting
  • Dypsis lutescens Flowering and Fruiting
  • Etlingera elatior Flowering
  • Ficus insipida Fruiting
  • Heisteria accuminata Fruiting
  • 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 andFlowering
  • Lagerstroemia speciosa Fruiting
  • Morinda citrifolia Fruiting
  • Musa acuminate Flowering andFruiting
  • Naucleopsis ulei 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
  • Thunbergia grandiflora Flowering
  • Virola guatemalena Fruiting
  • Virola sebifera Fruiting
  • Zammia sp Flowering

Profile of a Killing Crew   Leave a comment


Felipe del Bosque Blog Dec 12th 2011

Almost But Not Quite

The days are becoming drier, the sun is shining longer but there are still intermittent spells of cloud and light rain.  Although I wouldn’t put money on the fact, I think we have all but seen the back of the rainy season.  It won’t be too long though before everything becomes dry and dusty at which point everyone will bemoan the lack of water, except, of course, the visitors to the lodge.

As You Were

We had Roy Toft’s annual Photographic Workshop taking place at the lodge this past week.  The sun normally follows Roy to the Osa Peninsula and this year was no exception.  The guests arrived before breakfast and before they had time to unpack their bags, the Chestnut-mandibled Toucans landed in a palm tree in front of the restaurant to feed on the fruit. Breakfast was delayed as 8 happy photographers snapped away.  Not a bad start to the workshop.  The rest of the day continued in the same vein with troupes of Capuchin and Spider Monkeys making their way through the grounds.

The next day it was to be more birds in the grounds, and once again breakfast was put on hold as nature in action played itself out in front of the novice wildlife photographers.  The toucans were back in force, as were the Capuchin Monkeys, but what happened next was a once in a life time, if somewhat gruesome, opportunity for the photographers.  We at the lodge are used to the spectacle, but it is a surprise to most.  Some of the Capuchin Monkeys have learned how to catch the toucans and the photographers were treated to the scene of a massacre.  Held in morbid fascination, the photographers captured images of the demise of two toucans that were rendered apart by the monkeys, only the beaks remained to fall and hit the ground.

The next day they were practicing the art of macro photography and once again the wildlife complied.  Black and Green Poison Arrow Frogs were the subject of the morning shoot and in the evening it was the turn of the Red-eyed Green Tree Frogs.  They had a very successful day as the frogs appeared in abundance for the first time in many months.

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

Welcome Visitors

The rainfall has been encouraging a lot of insects to shelter in my cabin at night, especially when I am working with the lights on.  I have found a variety of moths on the window screens.  As the rain has been somewhat prohibitive in photographing anything outside, I just took advantage the fact that outside was coming to me.

Unidentified Katydid

Moths are frequent visitors but moths are not easy to identify.  This is one of the Automeris moths.  There are many Automeris species and they all have a common distinguishing feature.  The dorsal surface is muted in color but if something was to disturb the moth, it opens its wings to reveal two large orange eyes spots on the dorsal surface of the hind wings which serves to startle the would be attacker.  However when I tried to solicit a response from this individual, I only succeeded in causing to fly off.

Automeris sp

With some moths I just have to admit defeat for the present moment when it comes to identifications.  Rather I am  happy to enjoy their beauty and the fact that they chose to make an uninvited overnight stay on the screens of my cabin.

Unidentified Moth

Unidentified Moth

I have posted photos of the Rough-skinned Dirt Frog, (Craugastor rugosus), before, but juveniles.  One night as I went back to my cabin I found an adult sitting in the path.  I don’t find the adults that often so I managed to add that image to those of the young ones.

Rough-skinned Dirt Frog

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 83°F.  Average Daily Temp Low 72°F.

Average Daily Rainfall 0.46 ins.  Total Weekly Rainfall 3.23 ins

Average Daily Temp High 27.9°C.  Average Daily Temp Low 22.2°C.

Average Daily Rainfall 11.72 mm.  Total Weekly Rainfall 82.04 mm

Species List for the Week

Mammals

  • Howler Monkey
  • Spider Monkey
  • White-faced Monkey
  • White-nosed Coati
  • Agouti
  • Red-tailed Squirrel

Birds

  • Orange-chinned Parakeets
  • Red-lored Amazon
  • Pale-billed Woodpecker
  • Laughing Falcon
  • Black-hooded Antshrike
  • Chestnut-backed Antbird
  • Common Paureque
  • Wedge-billed Woodcreeper
  • Short-billed Pigeon
  • Long-billed Hermit
  • Stripe-throated Hermit
  • Spectacled Owl
  • Chestnut-mandibled Toucan
  • Blue-crowned Manakin
  • Cherrie’s Tanager
  • Golden-hooded Tanager
  • Palm Tanager
  • Summer Tanager
  • Bright-rumped Atilla
  • Dusky-capped Flycatcher
  • Golden-crowned Spadebill
  • Great Tinamou
  • Black-throated Trogon
  • House Wren
  • Black Vulture
  • Turkey Vulture

Reptiles

  • Cat-eyed Snake
  • Common Basilisk
  • Clawless Gecko
  • Golfo Dulce Anolis

Amphibians

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

Butterflies

  • Anartia Fatima
  • Glutophrissa drusilla
  • Heliconius erato
  • Heliconius sapho
  • Heliconius sapho
  • Hermeuptychia hermes
  • Magneuptychia libye
  • Marpesia furcula
  • Metacharis victrix
  • Morpho helenor
  • Morpho Menelaus
  • Philaetria dido
  • Phoebis argante
  • Pierella helvina
  • Pierella luna
  • Pyrgus oileus

 Plants

  • Aphelandra golfodulcensis Flowering
  • Bamboo Orchid Flowering
  • Black Alligator Tree Fruiting
  • Calabash flowering and fruiting
  • Cannonball Tree Flowering and Fruiting
  • Clusia rosea Flowering
  • Golden Trumpet Vine Flowering
  • Heisteria fruiting
  • Inga Flowering
  • Monkey Comb Tree Flowering
  • Figs Fruiting
  • Mountain Rose Flowering
  • Ox Eye Vine Fruit
  • Stinky Toe Fruiting

Capuchin Monkeys Eating Toucans   Leave a comment


Wildlife, nature, fauna and flora of Costa Rica.

A Typically Tropical Day

A typically tropical day here at Bosque del Cabo, on the Osa Peninsula in Costa Rica; warm and sunny during the day but later in the afternoon, the clouds started to gather and by the early evening it was grey and overcast.  Every night, almost on schedule, at six o’clock the rain comes down.  This year has been slightly wetter than normal for the wet season.  That makes it a good year for the frogs though.  The main amphibian breeding season is over and the numbers of individuals are starting to decline but there are still more than during the dry season.  It only takes a few rainless days followed by a torrential downpour to have some species rekindle their ardor

.Many of the trees are in fruit at the moment so flocks of tanager species can be seen in and around the grounds accompanied with cotingas, tityras, manikins and euphonias.  Some, like the frogs are resident and commonly seen on a daily basis, others, more elusive, make a rare but welcome sighting.  This week has seen a flock of Turquoise Cotingas, (Cotinga ridgwayi), both male and female feeding in the fig trees.

The ever present Capuchin Monkeys have been entertaining and horrifying everyone at the same time recently.  There have been sizable flocks of Black-mandibled Toucans, (Ramphastos ambiguus), feeding on figs.  Many of the visitors have gone out to get that once in a lifetime close up photo only to be confronted by the bloody spectacle of a pair of monkey paws throttling the life out of the bird then rendering it apart, consuming the flesh and finally dropping the large and distinctive beak to the ground.

Red-eyed Green Tree Frog Feature

Agalychnis callidryas. Hylidae. Phyllomedusinae. Osa Peninsula. Costa Rica.

Male Red-eyed Tree Frog, (Agalychnis callidryas), calling for a mate.

Red-eyed Green Treefrog literally describes the picture poster child of Costa Rica.  Anything that features the name Costa Rica will generally be accompanied by an image of this beautiful frog.  It is fairly widespread throughout the country in areas of wet or rainforest.  It is not easily going to be mistaken for any other frog, despite there being several different species of Red-eyed Green Treefrogs, they are all very distinctive.  The most popular tour by far at Bosque del Cabo is the “Sunset Tour”, which I lead every night at six.  Of course visitors have seen monkeys, sloths, macaws and toucans during the day, but for many the star of the daily nature show does not emerge until the sun has set.  As they breed all year round, more so in the wet season, I can almost guarantee that at least one male of this very popular wildlife sighting will be sitting calling, green bodied, blue and yellow barred sides with those bulging red-eyes simply inviting a photograph.

Red-eyed Green Tree Frogs are widespread throughout the moist forests of Costa Rica.  Here they can be found year-round, the males calling every night, but more particularly in the wet season.  During the day they tuck themselves away under the leaves at the top of the trees to escape the skin-drying effects of the tropical sun’s rays.  At dusk, as darkness descends, they awaken and begin the nighttime activities of feeding and reproducing.

They breed in still water so the pond is the best place to find them.  The males make their way to a perch at a lower level from which they will begin their amorous serenade.  If you stand and listen then you will hear the “Chuck, chuck” sound that many people mistake for a nocturnal bird.  During the dry season the calls will probably be in vain, the females are not interested at that time of year.  However, when the rains begin the situation changes.

The females are much larger than the males, their bodies have to accommodate all of the eggs.  They select a breeding partner for the evening depending on the bass of the male’s call, the lower the better.  She makes her way to the chosen mate who then climbs on her back.  She carries him to the water where she proceeds to absorb water through her skin which in turn fills her bladder.  With the male still holding on tight she then locates a suitable leaf overhanging the pond and will commences to lay her eggs.  As the eggs leave her body the male fertilizes them externally.  The 50 – 100 eggs are contained within a protective, clear gelatinous coating.

The larvae develop for approximately 7 or 8 days and eventually the egg mass liquidizes and the tiny tadpoles drop into the water.  Here they will grow and finally metamorphose into a miniature copies of the adult, leaving the water to face the challenges they have to overcome before reaching breeding status themselves.

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