Archives for 2020

What our animals are up to this month… December 2020 Edition

November 29, 2020 by Admin

By December, our native reptiles and amphibians should be dormant and sheltering somewhere warm for the winter. Unlike other animals which hibernate through winter, amphibians and reptiles do not undergo true hibernation; instead they enter a state of reduced activity.

Common lizards are one of the opportunistic species that make the most of mild winter weather by coming out of dormancy for brief foraging bouts. They will use these warmer spells to hunt for invertebrates such as worms, spiders and slugs before returning to their overwintering site. This behaviour is becoming more common as we are experiencing warmer winters.

You can encourage common lizards to your own garden by creating piles of rocks or logs for them to shelter in. Growing a variety of plants or building an insect hotel nearby will also attract a range of insects for common lizards to feed on, and they will appreciate having this food source on hand to take advantage of during the warm spells!

*Watch out for opportunistic common lizards foraging during brief periods of mild weather this winter and record sightings on the Dragon Finder app!*

Halloween, Folklore and Myths

October 27, 2020 by Admin

“Fillet of a fenny snake, In the cauldron boil and bake; Eye of newt and toe of frog, Wool of bat and tongue of dog, Adder’s fork and blind-worm’s sting, Lizard’s leg and owlet’s wing, For a charm of powerful trouble, Like a hell-broth boil and bubble.”

For many, the above passage will be familiar as a scene from Shakespeare’s Macbeth. For those who are not familiar, most will at least know that it is in reference to a witch’s brew. Amphibians and reptiles have long been associated with the occult, having deep rooted ties to ancient folklore and mythology. Though these links are not as strong in the present, the negative stigma surrounding these species has pervaded. What better time than Halloween to delve into these stories and perform some much-needed myth busting?

Did witches really go around carving out newt eyes, leaving blind newts to stumble around lost? The answer is no. In Shakespeare’s Elizabethan England, jobs such as midwives, herbalists and healers were easily misunderstood, and deemed witchcraft as a result. In an age predating modern medicine, people had to be more connected with nature to create medicines. They had to understand what was usable and what was not, which combinations worked for which illnesses etcetera. This makes complete sense, as we today still rely on nature for the base ingredients of many of our own medicines. These tradespeople relied on knowledge passed down through generations to create herbal remedies. To protect their livelihoods, their ingredients had to be shrouded in secrecy. This is no different to giant companies today like Coca Cola hiding the ingredients to their “magical brews”.

In order to keep their ingredients secret, they renamed a lot of what they used. This would also deter others from taking up the same practices; as animal body parts hardly sounds appealing and there’s no business in having everyone trained as a healer! If we look at Shakespeare’s cauldron, what was really being used was mustard seeds (eye of newt), buttercup (toe of frog), holly leaves (wool of bat) and houndstongue (tongue of dog). The use of body parts to refer to parts of plants was common within these circles. Eyes would refer to seeds, tongues to petals, guts to roots, tail to stem and so forth. Admittedly, adder’s fork did refer to an adder’s tongue and a blind worm’s sting referred to a slow worm’s tail. That aside, selling potions with mysterious names would prevent customers from simply going off and making their own potions. The witchy aura of it all also may have legitimised the healer and had consumers convinced that they were taking magical cures – not too different to the placebo effect we know of today.

Still, this does not answer the question of why there is such a gravitation towards reptiles and amphibians. Why do they inspire such revulsion? From medieval times, it was believed that all toads and frogs were poisonous. This is the case for some species, but certainly not within the UK. The fear stemmed from the fact that some amphibians can cause sickness or fatality if ingested – in particular, toads, as they release bufotoxin to deter predators when frightened. Furthermore, during breeding season, it is known that these animals can swarm in large numbers. In times past, animals swarming was not seen as a marvel of nature, but instead a precursor of evil. Think of a swarm of locusts for example. They can be found in such quantities that people feared that they were spontaneously multiplying. Their choice of habitat invoked further fear as swamps and stagnant pools of water were the antithesis of consecrated holy water. The list goes on.

However, it did not always use to be that way. Frogs used to symbolise fortune, rebirth, rain, fertility and heightened spirituality. The Egyptian goddess Heqet, occasionally depicted with a frog’s head, was the goddess of fertility and childbirth. Rain was a giver of life, allowing crops to grow and rivers to flow and consequently frogs became predictors of rain as they would gather in large numbers as the heavens showered. This was a trait that was also shared with other amphibians such as our toads and newts. Snakes symbolised immortality with their skin shedding, lizards represented regeneration due to their ability to regrow tails. As we celebrate Halloween, it is perhaps a time to reflect and rediscover the awe of the Ancient Egyptians and Mesopotamians. Rather than perceive the brilliant nature of metamorphosis as these species morph from egg to adult as something to fear, it is time to shift back to the perspective that it is a magic to be revered and protected at all costs.

Emily Robinson, London T.O.A.D Project Trainee

Croaking Science: Amphibians in the ‘Anthropause’

October 27, 2020 by Admin

On damp nights in the spring in temperate regions, amphibians emerge from their winter hideouts to migrate to their breeding pools. Nothing will stop their drive to reach water to spawn and so they brave a barrage of cars and artificial barriers along their route which often results in them getting squashed.

Amphibians have complex, biphasic life histories which makes their conservation challenging. Most species require high quality aquatic and terrestrial habitats which must both be connected by a transition habitat during migrations (Baldwin et al. 2006).

As urbanisation expands around the world, many aspects of wildlife physiology, movement patterns, population genetics and overall health are affected due to anthropogenic stressors such as habitat loss and artificial light pollution. The unprecedented expansion in transport infrastructure in the past century has had massive impacts on amphibian populations around the world (Beebee 2013, Glista et al. 2008). Roads fragment habitats and cause high mortality as well as being a significant source of chemical contaminants (Petrovan and Schmidt 2016, White et al. 2017, Bird et al. 2019).

Roads which bisect migratory routes severely restrict the dispersal of amphibians between their breeding areas and terrestrial habitat. This can have catastrophic impacts on gene flow and metapopulation dynamics potentially leading to population declines, genetic isolation and even extinction (Fahrig and Rytwinski 2009, Marsh and Trenham 2001). Therefore, mitigating road-kill and habitat fragmentation is a conservation priority (Puky 2005, Beebee 2013, Cushman 2005). Genetic bottlenecks as a result of fragmentation reduce the viability of populations and can leave amphibians more vulnerable to other synergistic environmental stressors such as climate change, pollution and emerging wildlife diseases (Cushman 2005, Laurence and Useche 2009). Urban fragmentation is known to decrease species diversity and abundance and coupled with wider habitat degradation such as edge effects and loss of breeding habitats, can make cities particularly challenging for amphibians (Bickford et al. 2011, Scheffers and Paszkowski 2012). At some field sites, mass mortality on roads can cause complete extirpation of anurans and salamanders within years (Cooke 2011, Hels and Buchwald 2000). With more and more cars on the roads, it is increasingly difficult for amphibians to avoid them.

Temperate amphibians such as the common toad have experienced significant and continuous declines. In the UK it is estimated that 20 tonnes of common toads (Bufo bufo) are killed annually as they migrate across roads to reach their breeding ponds, with up to 13,000 annual mortalities being recorded even at manned amphibian crossings. This has contributed to a 68% decline in their population size in the past 50 years at a rate of 2.26% per year. The severity of the population reduction means that these toads are no longer ‘common’ toads and could soon qualify as vulnerable on the IUCN Red List (Petrovan and Schmidt 2016).

The COVID-19 pandemic has caused immense human tragedy as it has spread around the world straining healthcare services and paralysing economic systems. Quarantine restrictions imposed by governments in order to slow the spread of the virus, have caused extraordinary disruption to our globalised society but have created rare opportunities for some wildlife species (Zellmer et al. 2020). As bustling metropolises slowed down they were occupied by usually elusive fauna; wild boars were seen roaming Barcelona’s quiet neighbourhoods, flamingos flocked to New Delhi’s lakes, river otters and puma stalked silent streets in Chile and sea turtles thrived on empty Brazilian beaches. A recent paper by Rutz et al. (2020) coined the term ‘anthropause’ for this rapid and unprecedented “global slowing down of modern human activities, notably travel.” It has resulted in profound short term environmental benefits such as improved air and water quality as well as reduced wildlife disturbance.

Research conducted during the Anthropause has highlighted both known and less known impacts that we are having on the natural world and is providing a unique opportunity to study wildlife populations during a time of reduced human presence all around the world (Forti et al. 2020, Zellmer et al. 2020, Bates et al. 2020). Monitoring the ways wildlife has responded to covid lockdowns in urban areas allows researchers to quantify the impacts human mobility is having on wildlife in the Anthropocene (the term given to our geological age, dominated by human activities) and potentially find strategies to mitigate biodiversity loss (Rutz et al. 2020, Stokstad 2020). This research provides invaluable insight into the mechanisms of human-wildlife interactions that will inform conservation for decades to come.

Lockdowns in spring and summer of 2020 meant fewer vehicles on the road which has significantly decreased road mortality for many species including amphibians. A “roadkill reprieve” this year may have made amphibian migratory journeys much safer according to Goldfarb (2020). A study by Grilo et al. (2020) calculated that 194 million birds and 29 million mammals are killed on European roads each year under normal circumstances while in Brazil, road mortality has superseded hunting to become the “leading cause of direct human caused mortality in terrestrial vertebrates” (Carvalho et al. 2014). This year they may not suffer the same fate. Simply driving less could have been “the biggest conservation action” taken by humanity over the past 50 years according to Fraser Shilling of the Road Ecology Centre at UC Davis and could have potentially saved the lives of 500 million vertebrates (Nguyen et al. 2020).

In March and April as traffic flows dipped by 73% across the US, many creatures received temporary respite from road collisions, with Californian mountain lion fatalities down 58% and a 48% decrease in roadkill deaths in Maine. Although much of the data focuses on large mammals, the same is true for smaller, less mobile animals such as amphibians, snakes and turtles (Katz 2020).

At amphibian crossings this spring in Maine, wood frogs, salamanders and newts were twice as likely to survive than in previous years, which is great news for these sensitive creatures that are very vulnerable to habitat fragmentation. Four amphibians successfully crossed the road for every one squashed this year, half as many as in previous years (Goldfarb 2020, Keim 2020).

Wood frog (Photo Credit: Brian Gratwicke)

A study by Manenti et al. (2020) examined the effects of the COVID-19 lockdown and reduced human disturbance on wildlife in Italy and describes both positive and negative effects on biodiversity conservation. As well as allowing wildlife to explore new habitats and extend their activity periods, species richness and reproductive success increased while roadkill diminished in temporarily quieter areas. Some negative ecological effects included reduced enforcement of regulations, and postponed conservation action such as invasive species management.

A decrease in road traffic led to significantly improved survival of migrating amphibians on Italian roads this spring at eight toad crossings. Data suggests that there was an 80-90% decrease in nocturnal road traffic at these study sites during the anthropause. Four hundred and eight common toads (Bufo bufo) and 16 agile frogs (Rana dalmatina) were recorded as roadkill in 2019, and this dropped to only 38 toads and zero agile frog mortalities in 2020. The median mortality of road killed amphibians at each site decreased from 53 individuals to only one in 2020 (with some sites recording no mortalities) indicating that an increased number of adults made it to their breeding pools this spring giving populations a much needed boost. Manenti et al. (2020) also surveyed transects in Liguria, Northern Italy to quantify the effects of reduced traffic on common wall lizards (Podarcis muralis) and Western green lizards (Lacerta bilineata) and found a similar 10-fold decrease in road mortality.

Many of the conservation benefits the Anthropause created are ephemeral, as traffic returned to baseline levels once economic activity restarted. Although breeding booms this spring may bring some respite to struggling populations, alone, they will not be able to counteract the extreme loss of genetic diversity as a result of population bottlenecks in the past.

The information collected over the Anthropause highlights the need to improve the landscape to make it safer for all wildlife and particularly amphibians (Merrow 2007). If we can alter our transport networks to counter the effects of large-scale urban development and increased transport infrastructure we could go some way to mitigating the catastrophic impact of habitat fragmentation. The observed benefits that limiting road traffic can provide for migrating amphibians could inform more decisions about temporary, focused road closures around the world in the future to replicate this effect and to better conserve endangered amphibian and reptile species (Manteni et al. 2020).

Building fauna tunnels and bridges across dangerous roads to link habitat fragments allows animals to cross safely (Dodd et al. 2004, Gonzalez-Gallina 2018, Vartan 2017). Road mortality decreases by up to 85%-95% with animals responding surprisingly quickly to the change as ecosystems are reconnected (Vartan 2019). Wildlife tunnel projects can mitigate the effects of fragmentation and have been shown to allow amphibians to move successfully between sites bisected by roads. Tunnels and drift fences reduce road mortality, promote habitat connectivity, and allow amphibians to colonise new ponds leading to population increases and expansion into reconnected habitat (Jarvis et al. 2019). These movement corridors also allow roads to be permeable to a host of other wildlife species like reptiles and small mammals (Purky 2005, Jarvis et al. 2019).

The incredible work done by volunteers at amphibian crossings who help migrating amphibians make it across roads (Petrovan and Schmidt 2016) could also contribute to sustaining population increases this spring from quieter road traffic.

COVID-19 has also highlighted how explicitly intertwined human and wildlife health are and the catastrophic impacts of the overexploitation of nature. Emerging wildlife diseases such as chytrid fungi and ranaviruses threaten amphibians around the world and their spread has been catalysed by anthropogenic trade in our globalised world (O’Hanlon et al. 2019). A slowdown in global trade and human flows as a result of COVID-19 could also have gone a way to mitigating the spread of the pathogens that imperil amphibians (Forti et al. 2020). Although this benefit may only be short-lived as economies restart, there is hope that better regulation of the wildlife trade, in order to decrease the chances that future novel zoonotic diseases spill over from wildlife reservoirs in the future, could benefit amphibians too. Since the wildlife trade is responsible for the translocation of many amphibian pathogens (Kolby et al. 2014, O’Hanlon et al. 2018) better regulation and enforcement of the trade in live animals could help stem the spread of emerging amphibian diseases and invasive species (Forti et al. 2020).

The Anthropause provides us with an excellent opportunity to reimagine our relationship with nature and our socio-economic systems so that biodiversity can flourish and acts as a reminder that biodiversity is essential for maintaining human health and wellbeing too.

The disruption to the economic status quo that the pandemic has created gives us a pivotal opportunity to consider a greener, more sustainable future where people and wildlife can thrive. In order to effectively stem biodiversity loss in the Anthropocene, we must use this pivotal moment to plan a green recovery which incorporates wildlife conservation into all economic rebound projects. In the UK this means not viewing the protection of great crested newts as a delay to construction (Howard 2020) but valuing them as integral parts of a plan to balance our economic and environmental ambitions. It is also a perfect opportunity to invest in road mitigation measures such as wildlife tunnels and fauna bridges to reduce the detrimental impact they can have on wildlife populations (Merrow 2007), with the added benefit of being excellent economic multipliers.

November 2020 Croaking Science article by Xavier Mahele

Bibliography

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Bickford D, Ng TH, Qie L, Kudavidanage EP and Bradshaw CJA (2010). Forest fragment and breeding habitat characteristics explain frog diversity and abundance in Singapore. Biotropica 42, 119-125.

Bird RJ, Paterson E, Downie JR and Mable BK (2018). Linking water quality with amphibian breeding and development: A case study comparing natural ponds and Sustainable Drainage Systems (SuDS) in East Kilbride, Scotland.The Glasgow Naturalist 27.

Carvalho NC de, Bordignon MO and Shapiro JT (2014). Fast and furious: a look at the death of animals on the highway MS-080, Southwestern Brazil Iheringia. Série Zoologia 104 (1).

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Dodd C, Barichivich WJ and Smith LL (2004). Effectiveness of a barrier wall and culverts in reducing wildlife mortality on a heavily travelled highway in Florida. Biological Conservation 118, 619-631.

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Keim B (2020). With the World on Pause, Salamanders Own the Road: Traffic is down thanks to the pandemic. That’s good news for amphibians looking to migrate safely The New York Times

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What our animals are doing this month… November 2020

October 27, 2020 by Admin

We’ve recently covered what our amphibians and reptiles are up to over the autumn months, the differences in their overwintering behaviour and where they may spend the colder seasons in structures such as hibernacula.

It might surprise many however to hear that November can be a month for sighting Common Frogspawn in the south of England. Common frogs usually begin breeding and laying spawn as spring commences – often with sightings in January and February into spring depending on their location in the UK. But areas in Cornwall do report sightings of frogspawn before winter even fully commences.

This behaviour could be due to confusion during mild autumn and winter months that we can experience now in the UK or might be a strategy to get ahead of the game in terms of breeding times – albeit it with a huge risk of freezing temperatures affecting the survivability of the spawn.

This could be one sign of more to come in terms of our amphibians adapting to the effects of climate change and seasonal differences their behaviour isn’t quite adapted to. It’s so important that we can monitor these yearly trends in our amphibian and reptile species to help inform our work at Froglife and you can help by submitting your sightings using the Dragon Finder App – available for free on Android and iPhone devices!

*Frogspawn in November? Surely not! But this sighting can occur in mild autumns in the south of England*

What our animals are doing this month… October 2020

September 23, 2020 by Admin

October is truly a season of change for our native flora and fauna. As the temperature drops, vegetation starts to die back and our days get shorter, our native amphibians and reptiles start to get ready to face the challenge of winter.

Why is winter so challenging for our native Dragons?! Amphibians and reptiles are both ectotherms, meaning that they rely on external sources of body heat compared to endotherms, such as mammals, which are capable and dependent on internal generation of heat. This means that amphibians and reptiles have to find a way to navigate through the drop in external temperature, frozen watery homes, reduction in water oxygen levels and, often unforgiving, winter weather.

Each species has clever adaptions and behavioural changes that they go through each year between September and November for them to survive this wintery challenge.

It is a common misconsception that all amphibians and reptiles hibernate over winter, even though they will all be seeking hibernacula at a similar time, the type they need can differ from species to species as well as if they hibernate or overwinter. For example, the common lizard will be spending October feeding on invertebrates in preparation for winter before hibernating, often in groups, amongst rocks or dead wood.

Whereas, our newt species overwinter and go dormant under rocks or buried in mud, but take advantage of milder weather to forage.

For more info on what individual species do over winter have a look at our fatastic amphibian and reptile fact files! Click here!

By early October most of our reptile species will have entered their winter hibernation. The majority of the UKs reptile species will have favoured hibernating sites, such as the Adder who will return to their wintering sites that they use each year. With Adders often basking in the last of the autumnal sunshine until the end of October when they become dormant for the colder months.

Some species, particularly slow-worms, common lizards and grass snakes, will make use of piles of dead logs, leaves or compost for the winter. It is important that reptiles are not disturbed during their hibernation period since it takes them longer to recover if they have to become active.

An amazing way to help our fantastic amphibians and reptiles is to consider them when planning your wildlife garden. One of my favourite things to do is create a hibernaculum, an amazing space for all amphibians and reptiles to hunt, forage and of course over winter. They are so simple to do and can make such a difference! If you are short on space you could also make a ‘toad home’!

Would you like to create more overwintering ad hibernating homes for wildlife? Create new habitats for emerging amphibians and reptiles in Spring?

Download our FREE Wildlife Pond Visualizer App, learn what you can do for nature and try out the fantastic Augmented Reality Feature!

For more information click here. Download here

We would love to see pictures of all your hard work! Send in your before and after photos or gardening selifes to info@froglife.org

Croaking Science: Red Alert! The alarming state of marsupial frogs

September 22, 2020 by Admin

Amphibians have evolved a fascinating variety of ways to produce and look after their young. Parental care occurs in many families, with either the mother or the father, or occasionally both, spending time and effort to give their young a better chance in life. Recent Croaking Science articles have described the glass frogs (July), where fathers guard incubating eggs on leaves above streams; Phyllomedusa tree frogs (August) where the parents enclose the eggs in folded leaves above water; Mannophryne stream frogs (September), where fathers guard their eggs on land, then transport the hatched tadpoles on their backs to safe water. This month, we look at the marsupial frogs, where mothers carry their developing eggs on their backs. As well as considering their reproductive arrangements, we look at their conservation status: overall, an alarming picture.

The Hemiphractidae are a family of New World frogs, composed of 118 species in six genera. They are distributed across Central and South America, as well as some Caribbean islands. They are very small arboreal frogs, with a primarily nocturnal lifestyle. The main distinguishing feature of the family is the storage and development of eggs on the backs of females, either externally or within a pouch (which has earned some the nickname of marsupial frogs). They also have unusually large embryonic external gills compared to other frogs.

Males of several species have been seen to actively place the eggs on the backs of females during amplexus, during which time they are assumed to contribute their half of the required gametes. They have mostly been seen to breed during wet seasons in tropical areas, as most frogs do. In northern parts of South America there are two wet seasons, a long one lasting from April until August and a shorter one lasting from November until January. Hemiphractid frogs have been seen carrying eggs during both of these, suggesting that they do not possess a strict reproductive timetable but carry out opportunistic breeding when conditions suit.

You can see a range of specialisations between hemiphractid genera, none more apparent than the egg-carrying strategy (to pouch or not to pouch). The genera that utilise enclosed dorsal pouches include Gastrotheca, Flectonotus and Fritziana. Cryptobatrachus, Stefania and Hemiphractus don’t have pouches, instead using mucosal secretions to keep the eggs in place.

Within the pouchless genera, Stefania stand out due to the development of young. In this genus there is no free-swimming tadpole stage, resulting in the hatching of froglets directly from the eggs carried on the female’s back. Female Stefania individuals have been found carrying up to 25 eggs on their back! With a gestation period of around 3 months, those kids are one heck of a burden. Within the pouched or “marsupial” species, the two belonging to the genus Flectonotus stand out due to their mysterious nature, with little research being conducted on either. It is known, however, that hatching occurs within the pouch and that individuals are then deposited into small bodies of water, such as in the ‘tanks’ enclosed by bromeliad leaves; they are at the stage of being well developed tadpoles, which soon metamorphose, without feeding. It is not clear why Flectonotus retains this requirement for a brief aquatic phase, rather than progressing to the froglet stage in the pouch.

Conservation status

Analysis of IUCN’s Red List status for the family Hemiphractidae shows 32% of species in the four threatened categories (critically endangered to near threatened), similar to the figure for amphibians as a whole. However, only 25% of species are in the least concern category, which provides a much more alarming picture. This is because 24% of species are listed as data deficient, and 20% more have yet to be assessed. This is the reality behind some of the global figures for the state of nature. In some parts of the world, especially the tropics, the state of our knowledge of many groups and individual species is very poor. Because of the continuing loss and alteration of natural habitats around the world, the expectation is that species whose status is poorly known are unlikely to be doing well. However, this is not always the case, as we show below for one species of hemiphractid frog.

The dwarf marsupial frog (Flectonotus fitgeraldi) was brought into the spotlight by a recent piece of collaborative research between researchers in Scotland, Trinidad, the USA, Portugal and Venezuela. This study aimed to clarify the conservation status of the species, by establishing an accurate picture of their distribution. Currently, IUCN lists the species as Endangered, but this status appeared to be based on no published original research. Finding these frogs is easier said than done, since they are sized between 2 and 3cm (roughly the size of a 2 pence coin). They have been reported to exist across the islands of Trinidad and Tobago, as well as northern parts of Venezuela. However, there was uncertainty as to whether these three populations fit within a single species, since there had been several cases previously when close examination of widely distributed amphibian species revealed the different populations to be divergent enough to merit description as separate species.

A frog sitting on a wooden surface

Description automatically generated — **Pictured:** *F. fitzgeraldi* male perched on a leaf, caught mid-croak by Paul Hoskisson

F. fitzgeraldi are most reliably found by identification of the plant species they use as homes and tadpole deposition sites. These are commonly bromeliads, heliconias and aroids. The larval young of F. fitzgeraldi are deposited in phytotelmata, small pools of water contained within plant structures. The hatching tadpoles are at a late non-feeding stage, having been nourished by yolk content of the egg. In the days following deposition in a bromeliad tank, tadpoles develop limbs and emerge from the water as froglets. Metamorphosis is normally complete within 5 days, during which the tail is reabsorbed and froglets graduate to become fully-fledged frogs.

In order to review the Endangered classification of F. fitzgeraldi, the study made use of molecular techniques as well as surveys over the course of several years. Genomic DNA samples were compared for sequence similarity to determine whether the populations in Trinidad, Tobago and Venezuela all belonged to the same species. Surveys were initially conducted to determine the hours of peak activity in F. fitzgeraldi and found that they exclusively call between 6pm and 8pm, roughly an hour either side of sunset. Based on this information, presence/absence surveys were carried out using the call to determine presence (seeing the frogs is difficult, and moving vegetation to attempt to see them disturbs the frogs) at locations across Trinidad, Tobago and Venezuela. These took the form of transects through forested areas, either on foot or in vehicles, while listening for the raspy calls of F. fitzgeraldi, which sound like running your finger along a comb. This presence/absence data was used to build up a map of their distribution.

**Pictured:** *F. fitzgeraldi* perched on a leaf

Results from the study showed the three populations belong to the same species, with no taxonomic changes needed. It was also shown that F. fitzgeraldi was distributed more widely across Trinidad, Tobago and Venezuela than previously thought. This, combined with the lack of evidence showing deforestation on these two islands, was sufficient to demonstrate that ‘Endangered’ is too extreme a label for the species. However, deforestation in Venezuela, mainly for cattle farming, was found to threaten the habitat quality of F. fitzgeraldi, so the study concluded that a categorisation of the species as ‘Vulnerable’ was appropriate.

**Pictured:** Female *F. fitzgeraldi*: left- showing slit on the back, entrance to the brood pouch; right- ‘pregnant’ female. Each bump is a developing embryo in the brood pouch.

Although F. fitzgeraldi is sheltered from mainland deforestation by the island refuges provided by Trinidad and Tobago, many other hemiphractid frogs do not share the same luxury. This means that habitat loss caused by deforestation poses a threat to species whose distribution is restricted to northern areas of the South American continent, such as Venezuela and Guyana. For this reason, species of the hemiphractid family must be monitored closely in these areas over the following decade.

The work on F. fitzgeraldi that we summarise here shows that detailed fieldwork can sometimes reveal that the status of a species is better than previously thought. It also shows the value of student expeditions, which can deploy significant numbers of enthusiastic young people to carry out detailed field research which would be prohibitively expensive otherwise.

Acknowledgements

We thank Paul Hoskisson and Joanna Smith for permission to use their photographs.

Further reading

Our account of the conservation status of F. fitzgeraldi is based on a research paper currently under review.

Cameron Boyle and Roger Downie
University of Glasgow

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