Category Archives: Amphibians

Research on Anuran Seconday Production

Msc student from Rio de Janeiro State University, João Souza,  is developing his fieldwork at REGUA for his research project aiming to establish how fragmented areas in the Atlantic Forest could affect secondary production of tadpoles.

One of the fragments chosen to be studied. There are 32 artifitial ponds where students conduct their experimental work (© Micaela Locke).

João also    wishes to    demonstrate    through his    research the    important  role of isolated    mother        trees in helping to maintain natural    ecosystem      processes. As  part of these    ecosystem    processes    he is    specifically    looking at net secondary yeld, however it is important to remember the previous stepraw primary yeld. Terrestrial ecosystems rely on the sun’s energy to support the growth and metabolism of their resident organisms. Plants are known for being biomass factories powered by    sunlightsupplying organisms higher up the food chain with energy and the structural      “building blocks of life”. Autotrophs are terrestrial prime yeld producersorganisms that      manufacturethrough photosynthesis, new organic molecules (carbohydrates and lipidsfrom raw inorganic materials (CO2, water,    mineral nutrients).

The energy from the sun is stored on the newly created chemical bondsbeing then source of energy to heterotroph organismsHeterotrophs are secondary yeld producersrather    consuming than producing organic molecules.   

Captured tadpole to be taken to laboratory (© Micaela Locke).

Net secondary yeld (NSY)    historically represents the    formation of living biomass of a heterotrophic population or group of populations  over some period of time. It’s known    that not all food eaten by an individual is      converted into new animal  biomass (NSY),  onlyfraction of the material ingested is assimilated from the      digestive tractthe remainder passes out as fecesOf the material assimilatedonly a fraction contributes to growth of an individual’s    mass or to reproduction — both of which ultimately represent net yeld. Most    of the rest is consumed by normal methabolims (like respiration). 

Student João Souza collecting tadpoles on one of the artificial ponds (© Micaela Locke).

 

João’s research may supply    important data highlighting the      importance of conserving      vegetation fragments – even      standing trees – to help maintain      essential natural ecosystem    processes like NSY. He    also wishes to understand how the group of anuransone of the      largest vertebrate taxa with many    threatened species, is affected by    the loss of vegetation. 

Anuran community in pasture puddles

Beatriz, Jeferson and Orlando having a look at the Anuran community in one of the studied pasture puddles (© Jeferson Ribeiro Amaral).

Among the few students who visited REGUA last year, a very atypical year in which most universities’ field trips were cancelled due to Covid-19 pandemic, PhD student Beatriz Ferreira proceeded with her research topic of evaluating how pasture management with isolated tree clumps decreases the effect of deforestation and encourages the presence of Anuran tadpoles in pasture puddles.

Anurans use these ponds for reproduction which become fundamental to their existence. Jefferson Ribeiro and Orlando de Marques Vogelbacher accompanied Beatriz on her last 2020 field trip to REGUA. They are both Biology PhD students and have taken beautiful pictures of flora and fauna found at REGUA.

 

Green-headed tanager close to the common area at REGUA (© Jeferson Ribeiro Amaral).

For the last 20 years, REGUA has been encouraging and supporting research carried out by national and foreign universities.

Research at REGUA is one of the main pillars on which we base our conservation mission in the upper Guapiaçu watershed. Ultimately, understanding the dynamics of nature allows us to acknowledge that Mother Earth’s environmental services are paramount to human permanence on the planet.

We hope continuing welcoming researchers and students this year.

A Burrowing owl taking care of her nest (© Jeferson Ribeiro Amaral).

Pans

A pair of Blacksmith Tree Frogs <em>Boana faber</em> in a "pan" (© Rodrigo Fonseca)
A pair of Blacksmith Tree Frogs Boana faber in a “pan” (© Rodrigo Fonseca)
Blacksmith Tree Frog <em>Boana faber</em> in a "pan" (© Rodrigo Fonseca)
Blacksmith Tree Frog Boana faber in a “pan” (© Rodrigo Fonseca)

One of the researchers who is carrying on his fieldwork at REGUA, Rodrigo Fonseca, has been studying the perception and colonization of reproductive habitats (puddles, flooded fields, streams, etc.) by anuran amphibians and the elements of the landscape (trees and shrubs) favouring this dynamic.

His study includes night field work, where he samples temporary and stablished puddles also capturing and identifying amphibian individuals. He is a Master’s student from the Post Graduate Programme in Ecology at the Federal University in Rio (UFRJ).

During his activities, he quite often comes across with the Blacksmith Tree Frog Boana faber, a species known to form small nests called “pans” where males vocalize to attract females, which in return will evaluate the nest condition and decide whether to use it or not. If the female chooses it, the male performs the bridal hug, also called amplexus, where together they release gametes into the water forming around 3,000 eggs inside the nest.

Smooth horned frog

One of the amphibians that we love to show guests that visit REGUA are the smooth horned frogs, Proceratophrys boiei  that are often found within leaf litter along the forest trails.   They sit waiting for passing prey, or hunt for spiders, beetles and other insects, with their wide mouth they can take relatively large prey and have been known to eat small frogs.

Smooth horned frog (©) REGUA

They remain stationary and move very slowly if found and picked up.  This is an Atlantic rainforest endemic species.    Listed as “Least Concern” by the IUCN  in view of its wide distribution along the range of the biomes, only 7% remains of the forest which provides its home.   Current research in our forests indicates that its population is unlikely to be declining, and with the restoration we are carrying out, we hope this situation continues as we increase the suitable habitat.

The smooth horned frog spawns in temporary slow-flowing water within the forest or on the forest edge.   This species is featured on the World Land Trust site and after all these years I would say it is one of my favourite frogs of our 72 species list.

Brazilian Gold frog

Measuring less than one cm in length, the Brazilian Gold frog also known as “Saddleback toad” or “Brachycephalus sp.” are some of the smallest frogs endemic to South East Brazil’s Atlantic rainforest. 

They are found at very high altitude, where they are adapted to low temperature and high humidity. As a result, the populations are isolated and form technically “sky” islands on mountain tops. Over 16 species have been described.   As one can see from the photo, these amphibians have three toes on each foot, and two fingers on each hand, in contrast to the usual five digits of most frogs. 

Brazilian Gold Frog Brachycephalus sp
© Nicholas Locke)

Whilst climbing in search of orchids in the recently purchased Lagoinha area with Helmut Seehawer last December, we came across a large number of these golden frogs in leaf litter.   On taking a photograph, one gave an enormous silent roar in protest and then leapt away a massive distance by our standards to safety. We left them to their lives in this isolated world.

Our thanks to Rainforest Trust who provided funding to purchase this land. It is located at around 1000m above sea level and nestles next to Lagoinha farm.

IUCN states that species here at REGUA are of “least concern” and very well protected from deforestation, but we hope that climate change and pollution won’t affect them adversely.


Dutch herpetologist at REGUA

Masters student Hidde de Graff enrolled at University of Amsterdam has come to stay for three months at REGUA studying amphibians.    Professor Wouter Halfwerk organised Hidde’s stay here with Brazilian Dr. Mauricio Almeida and he has been conscientiously at work in the field.

Hidde in the Forest (© Raquel Locke)

Hidde is been analysing sound tracks from deliberately located microphones recording night sounds in forest fragments as a way to detect and identify the amphibian species present.    Every quarter of an hour those frogs calling will be recorded and later as he studies the sonograms, he will be able to identify the species present.

Dr Mauricio carried out a similar survey a few years ago and Hidde will be able to compare the results and see if there has been any species change and evaluate how accurate his findings are in terms of species identification.

Come and see the amphibians at REGUA

The Atlantic Rainforest at REGUA is well protected and expanding, and one of the prime habitat quality indicator species are amphibians.  Are the populations stable or declining?

Proceratophrys appendiculata (©Nicholas Locke)

Researchers are always interested as their population numbers reflect air quality and air humidity levels, which in turn are affected by forest cover.   There are over seventy amphibian species at REGUA and with programmes in forest protection and expansion, all species appear to be in good shape.

One genus that attracts attention is the Atlantic rainforest endemic Horned frog which we found on the green trail recently.    Both Proceratophrys appendiculata (also known as Guenther’s Horned Frog) and Proceratophrys boiei were seen.   They live in the leaf litter in forests up to an altitude of around 1200m, and spawn in forest streams.

Both species are relatively common at REGUA and all visitors like to pick them up and get a closer look at them. They sit immobile and looking rather glum, patiently waiting to be returned to the ground when they hop off into the leaf litter and are quickly almost impossible to refind.

Proceratophrys boiei (© Nicholas Locke)

 

 

 

 

 

Professor Proudfoot’s Work!

Walking the 50km of trails at REGUA is fascinating for birders and naturalists alike. Altitudinal range spans 30 – 2000m and there is a richness of invertebrates and plants to match the diversity of birds that draws the majority of visitors to REGUA.    All classes of arthropod are present in abundance and there are many interesting patterns of distribution waiting to be identified and investigated.

Dobsonfly Corydalidae (©Andrew Proudfoot)

REGUA’s lodge garden has a roofed, whitewashed wall complete with mercury vapour lamp generating many new records of moths for the Reserve and for Rio State.    The wall often reveals a wealth of other interesting invertebrates such as this Dobsonfly (Corydalidae).   Many of these creatures are difficult to see in the forest probably because they are residents of the tree canopy.

In the forest there are chance encounters with exciting species such as the White Witch Moth (Thysania agripina)  Noctuidae with a huge wingspan.

December to Febuary is the Brazilian summer and usually a hot rainy season and time of maximum plant growth.   This is, of course, an excellent time for all insects and amphibians.   Whilst August to November is the Brazilian Spring and busy for birdwatching, it is also good for insects.    Only March to July are a little quieter.

Witch moth Thysania agripina (© Andrew Proudfoot)

There is a profusion of wonderful butterflies.  Some, like the 88, (Diaethria clymena) are very common.   The most famous neotropical butterflies belong to the Genus Heliconia, with their distinctive strap-shaped wings and bright colours.   These insects were shown to have co-evolved with their food plant, the different species of passion-vine (Passiflora). The vines put out new shoots irregularly and the butterflies must live a long time to be able to search out new growth and lay a full complement of eggs.

Another spectacular group of insect are the various species of huge Morpho butterflies which flit through the forest under-storey.

Diptera are interesting and diverse. There are three common sources of food that can provide for a profusion of flies: dung, carrion and some species of freshly emerged fungus. Parasitoid ichneumonids and tachinids search out the larvae of butterflies and moths whose living tissues they will feed on until they finally cause their death.

Ants are predators, roaming leaf and shoot for opportunities or different species will farm leaves with the help of fungus.

Volunteer Researchers (Lee & Peter) in the forest (© Andrew Proudfoot)

Spiders must guard against predatory wasps and some of these are very large indeed.

Beneath the placid exterior of the forest, termites work to undo the conversion of CO2 to sugar; every now and then a crash is heard acr

oss the forest as another giant tree succumbs to their tiny jaws.

There is much work to do to find out how many species of arthropod exist in these rich habitats.   We are only in the earliest of stages investigating how all these myriad species interact in Mata Atlântica.

Andrew Proudfoot
REGUA Volunteer

Frogs enjoy El Niño at REGUA

With the effects of El Niño, the weather here at REGUA has been very humid with much rain received over the last three months. It has been great for the trees which are growing rapidly .

Dendropsophus seniculus (©: Nicholas Locke)

The amphibians at REGUA have also loved the heat and humidity.   This tiny tree frog found in forests is an example of Dendropsophus seniculus, of the Hylidae family, a fairly common species found in the lowlands of the mid-Atlantic Rainforest ranging from Bahia to Sao Paulo.

Though IUCN’s Red list considers them “least concern” the loss of their habitat has affected population numbers and these amphibians are very important in the control of insects, especially mosquitoes and we are very happy to find some many species at REGUA.  Their presence certainly shows that the habitat REGUA has restored is working very well.

New amphibians for REGUA

In the last two years there have been further surveys of amphibians at REGUA by Vitor Borges, Carla Siquera, Thiago Silva-Soares, Mauricio Almeida-Gomes and Michael Patrikeev resulting in the addition of another 5 species to our list. The new species are: Brachycephalus didactylus, Dendrophryniscus brevipollicatus, Gastrotheca albolineata, Phyllomedusa burmeisteri, Scinax cuspidatus and Crossodactylus gaudichaudii. The latest of these was the G.albolineata (see photos) which is apparently very common but only found in the highest trees, so is rarely seen. These take out list to 53 amphibian species so far recorded within the reserve.

Male <em>Gastrotheca albolineata</em> at REGUA (&copy; Michael Patrikeev)
Male Gastrotheca albolineata at REGUA (© Michael Patrikeev)

Male <em>Gastrotheca albolineata</em> at REGUA (&copy; Michael Patrikeev)
Male Gastrotheca albolineata at REGUA (© Michael Patrikeev)