Doflein’s Salamander

Some salamanders are very strange beasts. None more so than the tropical Central American species in the genus Bolitoglossa. They can shoot their tongues to catch prey like a chameleon, they can shed their tail when threatened just like many lizards, and they breed entirely on land. They belong to the group of salamanders—the Plethodontidae—that have no lungs, relying on gaseous exchange through the skin. The bolitoglossines are sometimes called climbing salamanders because they can and do live in trees and shrubs, a fact difficult to accept when seeing one for the first time since they not only have webbed feet but appear stiff and ungainly. But the fleshy, webbed feet are deceptive. When planted on a leaf and arched they act as suction cups.

I was barely aware of the existence of these salamanders in the years I first became interested in reptiles and amphibians. They do not get a mention in the popular books available in the 1950s and 60s in Britain that were written by Doris M Cochran or Robert Mertens.

About 30 years ago, I was given a few to keep by whom I cannot remember and my records have disappeared. Individuals of one species were beginning to appear on animal dealers’ lists. That species was Bolitoglossa dofleini from Guatemala, Honduras and Belize. At the time there was no commonly used name. Now IUCN list the following: Alta Verapaz Salamander, Doflein's Mushroomtongue Salamander, Doflein's Salamander, Palm Salamander. It was first described and named by Franz Werner (1867-1939) after Franz Theodor Doflein (1873-1924) who collected the salamander on an expedition to Central America in 1898.

Doflein's Salamander
One of the ones I tried to keep 30 years ago

     

Only years later did I learn that my experience of trying to keep this species was the same as everybody else’s. They appeared to live and feed perfectly well but after a few weeks or months they became lethargic, shed their tails and died. I was annoyed and puzzled that I was unable to keep animals that initially had appeared fit and healthy. Had I got something wrong or did they have some disease that developed with time?

In 2004 a note appeared in Veterinary Record. The authors made the general observation that B. dofleini ‘is generally considered notoriously difficult to keep alive; most imported animals do not survive beyond the first two months after importation’. Three males and two females, recently imported into Belgium, became anorexic and apathetic over a one- to two-week period. Then the hands and feet appeared slightly swollen and began to point upwards. Finally, the tail was shed and the salamanders died 2 to 10 days later.

At this time there was growing realisation that the chytrid fungus, Batrachochytrium dendrobatidis, was having devastating effects on amphibian species throughout the world. The authors of the paper found large numbers of chytrid cells in the cornified layer of the skin all over the body. The origin of the infection could not be determined because the salamanders could have been in contact with other animals in transit to Europe or in the dealer’s premises from which they were obtained.

The suggestion the authors made was that proliferation of the chytrid in the skin might have compromised gaseous exchange in these lungless amphibians. Kidney damage in the form of hyaline droplets was also present but whether this was related to the presence of chytrid was not known. A strange finding in three of the animals was the impaction of the stomach with moss and wooden particles.

I remained puzzled after reading the report in Veterinary Record. While clearly demonstrating the presence of chytridiomycosis, I really could not decide if the animals had died OF or WITH the disease.

Around 1990 the only information I could find indicated that Doflein’s Salamander was found in lowland rainforest. I therefore kept them at temperatures appropriate to that low altitude in Central America. However, I began to wonder if the temperature was too high. Later publications showed an altitude range of 50-1500 metres in the wild including premontane to lower montane wet forest. I did not know where the ones I was given had been collected but if they were from, say, an altitude of 1000 metres, I should have tried keeping them 10°C below that of my simulated lowland tropical environment. I have found suggestions in online fora that people attempting to keep and breed these fascinating amphibians had also tried too high a temperature. In this respect, I read there has been controversy in the past over the altitudinal distribution of the largest of the bolitoglossine salamanders, e.g. B. dofleini, that rely on oxygen uptake through the skin. One view was that large lungless salamanders can only occur at relatively high altitude because the oxygen requirements of the tissues at the higher temperatures of lower altitudes cannot be supplied by the relatively small surface area of the skin. Others have contested that view. However, cutaneous oxygen uptake compromised by the presence of chytrid together with a high environmental temperature in captivity might just have created the perfect patho-physiological storm. 

I discovered that from their size the salamanders given to me must all have been females; males are much smaller. Collectors apparently searched the leaf litter and because the females tend to live there while the males prefer to clamber in the trees and bushes it was mostly females that were imported into Europe.

The only success at keeping B. dofleini I have come across is at Fort Worth Zoo. It was reported in 2012 that ten (all females) had been kept for 6 years. On arrival, all had been treated for chytridiomycosis. I have not seen any reference to the environmental temperature in their exhibit. I have been unable to find in the various papers, whether or not those exported for research have been kept successfully for any length of time.

Fortunately, no licences are now issued for the collection of any species of Bolitoglossa (which occur in Central and the north of South America). B. dofleini takes 10-12 years to reach sexual maturity. Thus a breeding population could, by uncontrolled collection of adults, be reduced to dangerously low levels very quickly. IUCN classify the species as Near Threatened.

It does, though, concern me that nobody has a method for breeding any species of Bolitoglossa in captivity—or at least if they have, nothing seems to have been published. The radiation in these salamanders has been so great that they represent 40% of all the tailed amphibians of the world. If—perish the thought—a captive-breeding programme became necessary to ‘lifeboat’ a conservationally important species, there would be very little background knowledge with which to start.

The only consolation of my experience with Herr Doflein’s Salamander was that I did get to see but not to record the remarkable tongue in action. It can be projected up to 31% of body-length in that species in under 20 milliseconds. The maximum velocity achieved was 7 metres per second and  the maximum acceleration 4500 metres per second per second. In other words the sticky tongue hits the prey at a speed of 25 km per hour, less than 0.02 seconds after launch. The performance of the paired tongue projector muscles ‘exceeds the greatest maximum instantaneous power output of vertebrate muscle by more than an order of magnitude’. 

Here is the video made by Stephen Deban, one of the authors of the paper on the high-power tongue projection in another species of Bolitoglossa, B. franklini:

Deban SM, O’Reilly JC, Dicke U, van Leeuwen JL. 2007. Extremely high-power tongue projection in plethodontid salamanders. Journal of Experimental Biology 210, 655-667. doi:10.1242/jeb.02664 

Feder ME, Papenfuss TJ, Wake DB. 1982. Body size and elevation in neotropical salamanders. Copeia 1982, 186-188.

Pasmans F, Zwart P, Hyatt AD. 2004. Chytridiomycosis in the CentraI American bolitoglossine salamander (Bolitoglossus [sic] dofleini). Veterinary Record 153, 153.

Scales JA, O’Donnell MK, Deban SM. 2017. Thermal sensitivity of motor control of muscle-powered versus elastically powered tongue projection in salamanders. Journal of Experimental Biology 220, 938-951. doi:10.1242/jeb.145896 

Wake DB, Dresner IG. 1967. Functional morphology and evolution of tail autotomy in salamanders, Journal of Morphology 122, 265-306.

The Curious Case of Climbing Newts

My eye was drawn to a post in the UK Amphibian and Reptile Groups Discussion Forum on Facebook which reported that as many as 50 Palmate Newts (Lissotriton helveticus) were found in reeds and low vegetation as high a three feet—nearly a metre—from the ground. Various comments followed as to why they may have been doing that when their breeding pond was close by. One of the comments was from Henrik Bringsøe in Denmark pointing out that he had written a paper on similar behaviour he and others had observed in the Smooth or Common Newt these days known as Lissotriton vulgaris, rather than the Triturus vulgaris we grew up with.

Bringsøe reported newts being found on the trunks of trees, on leaves and branches in vegetation about 40-50 cm above the ground and on the top of dead rushes at the edge of a pond. One was found 180 cm above the ground on the branch of an alder. Another, which was possibly attracted to invertebrates around a lamp, was found at a height of 2 metres on the wall of a house.

From Bringsøe, 2013

An obvious question is why this phenomenon has been so rarely observed. I could find no mention in either of the old standard books on British amphibians and reptiles, Smith and Frazer. Has it simply been missed or not reported?

There are all sorts of possible explanations for this little-reported climbing behaviour by amphibians which seem so ill-equipped for any sort of arboreal life. Indeed, there may be more than one reason with seeking food on vertical surfaces an obvious example. One suggestion that has not previously been raised might pertain to the climbing into vegetation near breeding ponds. Newts—both males and females—are known to use pheromones in courtship in their breeding ponds. Could it be that they are using an elevated position to ensure pheromones are further and more widely distributed in the surrounding air currents rather than relying on short-range diffusion close to the ground? Importuning—I’m here, come and get me’—could be what some of the climbing newts are up to, the unpaired ones climbing into reeds and shrubs to advertise their presence. 

Bringsøe H. 2013. Height-seeking habits of the Smooth Newt, Lissotriton vulgaris – a neglected behavioural trait. Mertensiella 19, 131-138.

Dusenbery DB. 1992. Sensory Ecology. New York: WH Freeman.

Frazer. D. 1983. Reptiles and Amphibians in Britain. London:Bloomsbury.

Smith M. 1954. The British Amphibians and Reptiles. Revised Edition. London: Collins

Waste Not; Want Not. Do Frogs Recycle Their Antifreeze?

Many advances in the biological sciences have come from what can be classified as—and funded as part of—agricultural research. Reproductive biology is one prime example but there are many others.

One advance the origins of which lie firmly in agricultural production is the recycling of urea. We were all taught at school that excess protein in the diet ends up as urea in urine with the nitrogen contained therein lost forever. But things are not that simple. Now it is known that in many animals, the urea is not simple dumped but can be broken down by bacteria in the gut and the nitrogen it contains recycled into protein.

It was the demonstration that urea, a form of non-protein nitrogen, added to the feed of farm ruminants, can be used within the rumen to make protein for growth or milk production that set off the interest in the recycling of urea under different nutritional and environmental regimes. It is not the ruminant’s tissues that are involved in breaking down the urea but the bacteria of the rumen. The bacteria then produce protein using urea as a source of nitrogen and this protein is digested and absorbed further down the alimentary canal. The history of the use of urea rather than expensive protein nitrogen sources was explained by my predecessor but one as Director of the Hannah Research Institute, James Andrew Buchan Smith (1906-2006), known throughout the world as ‘JABS’. Since those early days the recycling of urea nitrogen has been recognised in more and more organisms that produce urea as a nitrogenous waste product.

Amphibian species use high concentrations of urea in the blood for two main purposes: protection against dehydration and as an antifreeze. Some, notably the famous Crab-eating Frog (Fejervarya cancrivora) which can survive in sea water, build up high concentrations of urea in their body fluids in order to prevent the osmotic loss of water into the surrounding salty water. Other frogs that hibernate on land in sub-zero temperatures build up high concentrations of urea to act as a cryoprotectant. The high concentration lowers the freezing point of body fluids, preventing the formation of ice crystals.

In a paper published last year, a team in the USA produced preliminary evidence that the urea accumulated during hibernation in the Wood Frog, Rana sylvatica or Lithobates sylvaticus from northern North America, can be recycled into protein. Bacteria in the hind gut were found which could produce urease, an enzyme not produced by vertebrate tissues but essential for the recycling of urea nitrogen; more were present in winter than summer. Thus it is possible that as temperatures rise in spring, the bacteria become active, the urea is broken down and the products of that breakdown are converted into amino acids and hence protein.

Wood Frog
Brian Gratwicke [CC BY 2.0 (https://creativecommons.org/licenses/by/2.0)]

The findings on this frog indicate what could happen. However, there are some qualitative and quantitative pieces of evidence that would be more fully convincing of the first demonstration of urea recycling in amphibians. In mammals, specific urea transporters carry urea into the interior of the gut. Are they present in amphibians? Similarly, we do not know the magnitude and, therefore, the quantitative importance of any breakdown of urea to the overall nitrogen metabolism of these frogs at the end of hibernation. However, this could be another case of waste not, want not.  

Wiebler JM, Kohl KD, Lee RE, Costanzo JP. 2018 Urea hydrolysis by gut bacteria in a hibernating frog: evidence for urea-nitrogen recycling in Amphibia. Proceedings of the Royal Society B 285: 20180241. http://dx.doi.org/10.1098/rspb.2018.0241 

Frog Hearts and University Politics in 1950s London

When writing about an article in the famous series, New Biology, published by Penguin between 1945 and 1960, I was reminded of another influential article of the time and how its author came to feature—completely unintentionally—in a London academic promotion battle that turned into a loss to Britain and a win for Australia.

The article in New Biology in 1952 was on the working of the frog’s heart which has three chambers, two atria and just one ventricle into which both atria empty. George Eric Howard Foxon (1908-1982*), then Reader in Biology at Guy’s Hospital Medical School, outlined what he called The Old Story, dating from the mid-1800s, of how oxygenated blood from the lungs is preferentially diverted to the rest of the body after it (along with blood from the body) enters the single ventricle. According to this scheme, oxygen-rich and oxygen-poor blood do not mix to an great extent in the ventricle, and blood is pumped sequentially into the three major arteries: blood low in oxygen from the body is the first to leave for oxygenation in the lungs and skin; as the ventricle continues to contract, the next lot goes to the body generally while the blood remaining until the final squeeze of the ventricle, that rich in oxygen having arrived from the lungs, goes to the brain. Mixing of oxygen-rich and oxygen-poor from from the left and right atria was, it was argued, prevented by the trabeculae of the ventricle forming rough compartments.

Over the decades there had been doubt cast on this ‘old story’ notable amongst them the observation that there was no difference in time of movement of the blood into the three main arteries. In other words, the story of a sequential separation of flow into those arteries appeared to be wrong.

Foxon sat himself the task of trying determining if the blood from the right atrium was kept largely separate in the ventricle from that entering from the left atrium. He was following up work published in Paris in 1933 in which it had been found that particles from Indian-ink injected into the pulmonary vein were found in all three arteries; on other words there was mixing. Similar results, using starch grains, from the other side of the heart had also been reported.

This is Foxon's diagram of the frog's heart

Foxon used an X-ray opaque suspension of thorium dioxide to follow its passage through the heart by taking a series of X-ray photographs in rapid succession—pioneering technology in those days. While blood from the lungs via left atrium was found to fill the left side of the ventricle that from the body filled the right side. However, during ventricular contraction the movement was found to be so violent that all the blood was mixed together in the conus arteriosus, from which the major arteries (three on each side of the body) arise, such that there was no separation as the blood was forced into the three arteries.

But that story did not last. Later research using more modern technology showed that deoxygenated blood from the right atrium is directed preferentially to the lungs and skin through the pulmo-cutaneous artery. More and more evidence was produced to indicate Foxon was wrong; the ‘old story’ was right in essence if not in detail. It is that version of events—of partial separation of blood streams from the two atria during ventricular relaxation and contraction and flow through the conus arteriosus—which has entered the textbooks.

However, circulation within the heart and major arteries of the amphibian heart has continued to excite the interest of those exploring what happens in different environmental and physiological conditions, in diving and conditions where concentrations of oxygen in the immediate environment are low for example, as well as in several different species. Technological advances in measuring blood flow and pressures in small blood vessels have meant that physiological measurements can be done in conscious undisturbed animals, in the relatively large Cane Toad^† (Rhinella marina) for example. In Foxon’s day, ‘pithed’ frogs—those in which the brain has been destroyed—were used perforce. Thus physiological control mechanisms affecting pressures in the various blood vessels may have been disrupted compared with an intact animal in the wild.

The story does not end there. More recent research indicates that there are conditions in which there is a high degree of mixing of the two blood streams within the heart, as claimed by Foxon, and others in which there is a high degree of separation. One example will suffice: in the resting Cane Toad at 10°C mixing was 85% complete but at 30°C mixing was only 17%.

So having been dismissed as anomalous results, Foxon’s conclusions have been supported—in some conditions. The great mistake by a number of authors was to assume that what happens under particular experimental conditions happens under all, as an invariant mechanism for operation of the frog’s heart. Variation in the amount of blood directed to various parts of the body through the three major arteries and variations in mixing of the two streams of venous blood, provide a whole host of different tactics that can be be employed by an individual frog, or by different species, to enable them to adapt to the vicissitudes of life amphibian.

It is, it should be noted, misleading to state that blood arriving into the right side of the heart is, as in mammals, deoxygenated after passing through the tissues of the body. This is because some of it has passed through the skin and skin is an important site of oxygen uptake in amphibians. I have read studies in which the skin in resting animals accounts for a third of all oxygen uptake. The lungs provide a greater proportion during activity or if the oxygen content of the water or the water film over the skin falls. The implication is that blood from the right side of the heart recirculated through the body will still be supplying some oxygen to the tissues in frogs but not, of course, in mammals.

As an aside, a dangerous side effect of the study of ‘types’ as the main part of courses in biology was the impression created in the student that as one moved from the type fish to the type amphibian and so on to the type mammal, there was a progress from a primitive to an advanced organism. It was, therefore, easy to get the impression or to be told that the poor old frog having just three chambers in its heart was in some way inferior to the mammal or bird which had evolved four and had achieved the perfect double circulation, i.e. complete separation of blood streams through the body and through the lungs. Foxon was quick to dispel this line of thinking:

..the heart of the frog does not represent an unsuccessful attempt at the division of the heart into arterial and venous sides. It seems we must regard the frog not as any form of intermediate stage between fish and higher vertebrates but as an animal suited par excellence for a true amphibious made of life…

Foxon appeared in the biography A.J. ‘Jock’ Marshall (1911-1967), his opposite number at St Bartholomew’s Hospital School. Both schools fell under the aegis of the University of London. Foxon and Marshall were Readers and heads of their respective departments. The biology departments within the old medical school were, even by the standards of the day, very small with formally a lowly rôle; their teaching consisted of instilling a knowledge of elementary biology in very junior medical students who had taken on the study of medicine never having studied a biological subject at school. They had no honours students but could ,of course, do research and supervise postgraduate students. Through the latter route they could be promoted to Professor. Indeed Mr Foxon (he did not have a Ph.D. just like many British academics of the time) became Professor Foxon in 1955.

In 1957 Jock Marshall was put forward to the University by his medical school for promotion. Foxon encouraged Marshall, thinking the whole matter a formality for one so clearly qualified. But Marshall’s case was blocked by one external member and one internal member of the committee, as explained in detail by his widow here. Marshall was incandescent with anger at his treatment. The Cambridge mafia he blamed; the formerly supportive internal member was reliant on the external member for supporting his candidature for the Royal Society. The treatment Marshall received in London appears to have been the main reason for his looking for a job in his native Australia. He left to become the first Professor of Zoology at Monash University in Melbourne in 1960. However, he managed a parting shot at the internal member of the committee (who was elected FRS in 1958) who later approached him in a friendly manner: 'I told him to "Piss off you little bastard". He pissed off.’

Foxon, a Cambridge graduate who had previously worked in Glasgow University in the unenviable job of Assistant in Zoology (essentially the Professor’s dogsbody in a Scottish university) and at University College, Cardiff before, being appointed to Guy’s, continued his research on the heart and circulation in vertebrates.

Günther's Golden-backed Frog (Indosylvirana temporalis)
Sri Lanka, 2013
How was its heart working?

*Date of death is incorrect in the archives here

†The world seems to have adopted the Australian name for this South American species, introduced into the cane fields with a devastating impact on the wildlife. Until recently it was also and inaccurately called the Marine Toad (Bufo marinus).

Foxon GEH. 1952. The mode of action of the heart in the frog. New Biology 12, 113-126

The following can be referred to for some idea of the amount of work that has gone into determining how the frog heart and circulation work:

Gamperl AK, Milsom WK, Farrell AP, Wang T. 1999. Cardiorespiratory responses of the toad (Bufo marinus) to hypoxia at two different temperatures.

Graaf AR de. 1957. Investigations into the distribution of blood in the hear and aortic arches of Xenopus laevis (Daud.). Journal of Experimental Biology 34 143-172

Hedrick MS, Palioca WB, Hillman SS. 1999. Effects of temperature and physical activity of blood flow shunts and intracardiac mixing in the toad Bufo marinus. Physiological and Biochemical Zoology 72, 509-519

Hillman SS, Hedrick MS, Kohl ZF. 2014. Net cardiac shunts in anuran amphibians: physiology or physics? Journal of Experimental Biology 217, 2844-2847

Langille BL, Jones DR. 1977. Dynamics of blood flow through the hearts and arterial systems of anuran amphibians. Journal of Experimental Biology 68, 1-17

Pinder AW, Burggren WW. 1986. Ventilation and partitioning of oxygen uptake in the frog Rana pipiens: effects of hypoxia and activity. Journal of Experimental Biology 126, 453-468

Spring in Hong Kong: Brown Tree Frog

April is the height of the breeding season for many Hong Kong amphibians. Our correspondent found this Brown Tree Frog (Polypedates megacephalus) in the bushes of a garden in Kowloon Tong earlier this week.

This species is a foam nester positioning the nest of foam whipped up by the hind legs above the water line on a branch or on the side of a tank or a well.

Captive breeding of water frogs

There have been enormous advances since I started to keep amphibians sixty years ago. Recently, I was pleased to see further evidence of progress in a paper describing scientifically-based methods for the captive breeding of water frogs.

Even developing the methodology for common species to breed under controlled conditions gives a pretty good idea of where to start with the rescue of an endangered related species should that be necessary. In addition, of course, it tells you a lot about the physiological requirements and the conditions that trigger reproduction or, if conditions are not right, that inhibit it. 

This paper in the BHS’s Herpetological Bulletin by Christopher Michaels (now at the Zoological Society of London) and Kristofer Försäter working in England and Sweden describes the breeding of four species of water frog, Pelophylax. This is how they began the Discussion section of the paper:

Pelophylax sp. rely on well warmed, sunny areas of relatively still water with rafts of  floating vegetation and rarely stray far from water. They are heliophiles and actively bask, exposing themselves to the heat and UVB irradiation of direct sunlight (Michaels & Preziosi, 2013). Historically, indoors enclosures for amphibians were typically lacking in UVB provision and thermal gradients. With increasing understanding of amphibian lighting requirements and the availability of technology to meet them, indoors husbandry for water frogs is now much more easily achievable. Our captive enclosures were designed to recreate the UVB rich, brightly lit and warm environments inhabited by water frogs in nature and these conditions proved successful in maintaining and breeding this genus indoors.

Michaels CJ, Försäter K. 2017. Captive breeding of Pelophylax water frogs under controlled conditions indoors. Herpetological Bulletin  142, 29-34.

The University of Hong Kong was a site for more than birds in the 1960s

In the 1960s, the University Compound’s pathways teemed at night with the toad, Duttaphrynus melanostictus (formerly Bufo melanostictus), along with introduced Giant African Snail, Achatina fulica.

Duttaphyrnus melanostictus

The lily pond had large numbers of Guenther’s Frogs (Sylvirana, previously Hylarana guentheri).

Lily pond, University of Hong Kong, constructed in the early 1950s. The trees

were non-native. From Mellor, B. The University of Hong Kong, An Informal

History.  Hong Kong University Press, 1980

After heavy rain, the gardeners disturbed a couple of the microhylid, Kaloula pulchra, outside our lab building, the old Building 15 of the medical school (which by 1965 had moved to its new quarters on Sassoon Road).

Kaloula pulchra

The same location revealed a couple of Brahminy Blind Snakes under an old flowerpot. This species, now going under the name of Indotyphlops braminus, has been introduced into many parts of the world in...flowerpots.

This photograph from 1950 shows a University Congregation processing along
Pokfulam Road. I found Kaloula pulchra over the wall to the right, 17 years later
All the building in view have been demolished. From Mellor 1980

Street lamps and flats had the Oriental Leaf-toed Gecko, Hemidactylus bowringii. They often looked thin and underfed like the one I photographed.

Hemidactylus bowringii

A squad of gardeners looked after the compound and cleared fallen leaves. Snakes were, therefore, not to be expected. However, we did one spot a couple of times an Indo-Chinese Rat Snake, Ptyas korros, on the ground at the base of a tree directly below our balcony at 3 University Drive.

The only other snake seen took me by surprise. I opened a lab drawer containing glassware one morning to find a White-spotted Slug Snake (Pareas margaritophorus) less than happy at being disturbed.

If only digital camera traps had been invented in the 60s, we might have got an idea what, if any, mammals, other than rats, mice and domestic cats and watchmen were living in or visiting the Compound. A Chinese Ferret Badger (Melogale moschata) or two would be my bet.

Oliver LA, Prendini E, Kraus F, Raxworthy CJ. 2015. Systematics and biogeography of the Hylarana frog (Anura: Ranidae) radiation across tropical Australasia, Southeast Asia, and Africa. Molecular Phylogenetics and Evolution 90, 176-192. http://dx.doi.org/10.1016/j.ympev.2015.05.001 

Hedges SB, Marion AB, Lipp KM, Marin J, Vidal N.  2014. A taxonomic framework for typhlopid snakes from the Caribbean and other regions (Reptilia, Squamata). Caribbean Herpetology 49, 1–61.

European Amphibians and Reptiles: A New Field Guide

Field Guide to the Amphibians and Reptiles of Britain and Europe by Jeroen Speybroek, Wouter Beukema, Bobby Bok and Jan Van Der Voort and illustrated by Ilian Velikov. London: Bloomsbury.

There is no greater delight for those of us who live in a country with few species of reptiles and amphibians than seeing active lizards, amphibians and chelonians in southern Europe. With the thought of a Naturetrek trip to Albania in a little under three weeks, I wondered if there was anything more suitable to take with us than the 2002—and latest—edition of Collins Field Guide to the Reptiles and Amphibians of Britain and Europe that was written by Nick Arnold. As a field guide I find that book extremely irritating in that descriptions, illustrations and distribution maps of a species are in different sections of the book. I also thought I should be au fait with the inevitable taxonomic inflation that must have occurred. Hence, I found the almost identically titled but differently authored book from a different publisher that appeared last year.

I do not envy anybody the task of producing a field guide or even a check list. What does one do when a paper is published that splits a species on the basis of the phylogenetic species concept or genetic species concept rather than the biological species concept? And how does one then present that evidence in relation to the morphological semi-splitters of the past who created a new subspecies for virtually every locality specimens were collected from? 

Molecular systematists have had a whale of a time generating data on European reptiles and amphibians but you can take it from the preceding paragraph that I am by no means convinced that many of the species being described on the basis of differences in a few genes are ‘good species’ that hold up to the scrutiny of the biological species concept. Returning to the writing of field guides, authors tend to fall into the trap of having to appear modern by including every ‘split’ and, therefore, every change in taxonomy proposed. I will return to this question later.

The new book is clearly written as the herpetological equivalent of the area or country guide for birdwatchers (who come in many different guises and with different interests). The authors, before moving on to the description of individual species, devote chapters to: the diversity and origin of the European species, including the retreat to the separate refuges in the south during the Ice Ages and then re-colonisation as the ice melted; advice on how to, and where to, watch the European species; the identification of amphibian eggs and larvae. The diversity chapter includes a section on threats, such as the spreading of disease by herpetologists themselves, and conservation efforts. There is also complete checklist of species.

How does it compare with Arnold’s book of fourteen years earlier? For that comparison, I will divide this review into four parts.

Firstly, as a field guide, Speybroek et al. is much better. Descriptions, maps, illustrations and photographs are close together. However, it is not perfect because each species (or closely related groups of species) does not start at the top of a page. The publishers seem to have been trying to ensure that the book fitted into a set number of pages, in this case 432. However, in doing so, they have been wasteful of space. The illustrations are too big for the amount of information they convey. The whole design could have been much ‘tighter’ and the book, therefore, lighter in the pocket or backpack. The book weighs 740 g covering 219 species. The Collins Bird Guide for Europe covers over 700 species but weighs just 700 g.

The illustrations are more extensive and, ignoring the excessive white space, are good but no better than those of Denys Ovenden who illustrated Arnold’s book. There are some oddities. For example, the main illustration of the Ibiza Wall Lizard is captioned ‘brightly coloured individual’ and looks nothing like any of the lizards I have seen on Ibiza (although there are photographs of this form on a few websites). The photograph on the next page, from an introduced population on Mallorca, is however typical of those usually seen. Perhaps some of the species needed several illustrations to display the range of local variation in coloration.

Secondly, as a guide to the taxonomic changes or the authority on which changes have been made, this book falls short. The description of what happened during and after the Ice Ages is not linked to possible speciation and taxonomy The explanation under the heading ‘New species, new names’ is superficial. I have touched on the difficulties in drawing up a definitive list of species. It seems to me that the authors—and they are not alone—have adopted as species whatever those proponents of species concepts other than the biological species concept have proposed as species. But they do not say so or comment in any way on which species concept(s) they consider valid. The authors conclude the section: ‘Luckily, the majority of European amphibian or reptile species has nowadays been studied from a genetic viewpoint, making future name changes increasingly less likely, but never entirely out of the question’. Wanna bet?

Thirdly, In terms of biology, there are some serious omissions. It is mentioned that the two Bombina species hybridise but there is no mention of the narrow hybrid zones that have been studied extensively and which have contributed so much to knowledge of speciation and introgression. There is also no mention of the special place of the Edible Frog in biology; there is not even an explanation of the ‘kl.’ in its modern scientific name. Given its and other European forms’ key status as examples of hybridogenesis, in this case between the Pool Frog and the Marsh Frog, it does seem odd that the phenomenon is not even given a mention. Compounding this omission is the appearance of the distribution of the Pool and the Edible frogs together on one map and of the Marsh Frog on another. And yet the authors found lots of space for the itemisation and description of subspecies rather than simply the extent and nature of geographical variation. And, yes, you can take it that I regard the whole concept of subspecies and formal trinomials as deeply flawed.

Fourthly, in terms of geographical coverage, Arnold includes the Canary Islands and Madeira; Speybroeck et al. does not. I cannot understand why Britain was included in the title or included in the publisher’s British Wild Life Field Guides series. Yes, the maps include the distribution in Britain, but anybody seeking information on British reptiles and amphibians would be better looking elsewhere. 

In conclusion, while I found myself disappointed by the lack of coverage of some topics, as a field guide, the new book wins simply on the grounds of better arrangement of descriptive text, illustrations and maps. It is the one I will pack.

Writing such a book as this cannot have been an easy task, with decisions on what to leave out being a lot harder than what to keep in, but throughout the enthusiasm of the authors and illustrator shines through. For example, Jan van der Voort, a civil servant whose photographs appear throughout the book, has photographed every species in Europe. Who can resist the end of the Preface by Jeroen Speybroeck:

There is nothing quite like the the enchantment offered by a sizeable frog chorus in a Bulgarian swamp comprising a mixture of tree frogs, fire-bellied toads, green toads, spadefoot toads and water frogs. Reptilian thrills are plentiful, such as finding your first chameleon, bumping into mating tortoises, or experiencing the thrill of chasing down a feisty whip snake. I hope this book will foster the fascination in many more people, albeit always with respect for the animals and the conservation of them and their natural environment.

Amen to that.

Keeping Reptiles and Amphibians: Enthusing Young Zoologists

Keeping reptiles and amphibians, small mammals and birds in captivity was the accepted way of finding out about animals and many professional biologists who have made major contributions to their fields were enthused during their schooldays by the animals in their aquaria, vivaria, cages and aviaries.

Since the 1950s, knowledge of how to keep and breed small animals has advanced by leaps and bounds. From statements in books of the time that reptiles do not breed in captivity, breeding is now routine to the extent that captive-bred reptiles rather than birds abound in pet shops in Britain. Much, if not most, of that increase in knowledge came from amateur keepers, not from those working in zoos.

The general public is now far more sympathetic to reptiles and amphibians than they were since they have the opportunity to see and handle specimens at school and in zoos or specialist collections, or at home. The health and welfare of captive specimens has increased alongside an increase in veterinary participation (unheard of in the 1950s and 60s). Captive animals have increasingly become ambassadors for conservation, as well as temporary repositories for endangered species. That is all on the plus side.

On the minus side, the fancier mentality has taken hold, joining aviculture and fish-keeping in undermining the good reasons for keeping animals in captivity. The many colour forms of species forged by natural selection, are a sad travesty of the real thing being produced by a psychological state (plus a desire for profit) that I neither understand nor condone.

I have started another blog to cover the history of keeping small vertebrates in relation to the advances that have been made in the past century. In other words, some of the many things that interest me and have kept me interested as a sideline to my professional research interests for the past fifty-six years. At that site, you can download the only books we had available in Britain then and see just how limited our knowledge was as on how to keep and breed reptiles and amphibians, in particular.

The new site which will run in parallel with this one is at:
http://waicblog.wordpress.com

Donors of Reptiles to London Zoo 1915: 4. Harold Duncan Foster

The first example of an amateur reptile keeper I have found so far from the list given by Clin Keeling of those individuals who donated specimens to London Zoo around the time of the beginning of the First World War is Harold Duncan Foster. He gave two Slow Worms, a Delande's Gecko†, a Green Lizard, two European Tree-frogs, a Fire-bellied Toad, a Yellow-bellied Toad and two Great Crested Newts.

In the 1911 Census he is shown at the same address, namely, 43 Queen's Grove, St John's Wood — only a short walk from the Zoo. Born in Marylebone, he was a colliery owner, single, and employed a parlourmaid, another servant and a cook.

He married Alice G Anderson at Marylebone in 1913. Was it a coincidence that his reptiles and amphibians went to the Zoo in 1914? Or was it a case of me or those creatures? Alice died in Hampstead in 1934 aged 52.

Harold Duncan Foster died, a widower, in Hampstead in 1955, aged 71.

There is information on his family history at:
http://www.dannebrog.biz/whieldon/furley.pdf

†Delaland's Gecko?