NOTES ON OUR GENETICS PROJECT & MORE
Italian & Balearic Forms of Testudo hermanni hermanni:
As of 2017, the western subspecies of Hermann’s tortoise (Testudo hermanni hermanni) remains poorly understood in the United States despite our efforts to educate the general public. Few have the pleasure of possessing legitimately pure specimens and even fewer can claim they have specific strains or locales. As we already know, the strains making up this subspecies in nature are noted with quite a bit of speculation, particularly on the mainland of Italy. Some simply do not “believe” in the separation of subspecies and certainly not in geographical variants. This of course poses many issues in working to keep this chelonian pure throughout the world. Although genetic findings have revealed differences between them and phenotypic traits often back it up, much of this information continues to be ignored. Hermann’s tortoises are an utter mess in human care with keepers mixing animals from different parts of their range and allowing them to breed. The trouble does not stop there. Even in the wild, bastards, which are clearly the result of T. h. hermanni crossing with its Balkan or eastern cousin Testudo hermanni boettgeri are located. This means great danger for the fate of the western tortoise with impurity being one of its biggest threats. The common eastern tortoise has regrettably been released in some areas where the western historically occurs. They surely survive and inevitably breed with the native tortoises creating wild hybrids. This is particularly disturbing as most cross-bred animals are typically encountered in captivity, not in nature. With the exception of the Valley of the Po in northeastern Italy where the possibility of natural integration may take place, the eastern and western subspecies are disconnected from each other, Vetter et al. 2006. It is at this location that the two meet by the Po River which flows eastward in the northern range of the country. Contradictory conversations I have had with knowledgable sources suggest several possibilities concerning this area. This very well may be the distribution border for the subspecies or the animals found there may be the result of mixing via releases over the course of time. Tortoise keeping is no rarity in Europe, therefore, released pets are a very real threat to otherwise pure populations of T. h. hermanni. Reports suggest that when a bastard Hermann’s tortoise is met anywhere else within its western range, it is the result of human action only. This is a fine example of how once again man is to blame for the decline of a chelonian species. In addition, habitat destruction and over-collection are also factors to survival. The western subspecies is currently recognized by the IUCN Red List as Endangered B1+2abcde ver 2.3 and continues to decline with some forms approaching extinction.This does not mean that all hope is lost. Here at Garden State Tortoise, Testudo hermanni hermanni has long been a passion species with much of my life being dedicated to them. While I may not be able to send tortoises back to nature, I do believe that our efforts in keeping them nothing less than absolutely pure will help to brighten their overall future. Along with actively partaking in other conservation measures concerning them, the practice of maintaining the tortoises under naturalistic conditions and within their designated forms has been a positive experience. This is a summary of the populations I preserve under my care, genetic research and how they have fared in the northeastern United States over the years.
Testudo hermanni hermanni has remained a flagship tortoise for my wife and I with my first encounter dating back to 1991. This is when I received my first pet tortoise from my Italian grandmother, a hatchling specimen from Apulia, Italy. At the young age of nine, this animal captivated me beyond belief and I spent the next two decades allowing myself to become completely consumed by them. I have been able to legally acquire various known strains through Italian and Spanish ministry approval, United States Fish and Wildlife consent and proper CITES documentation. It was a grueling, expensive and exhausting process which took several years to complete. Following the successful importation of these tortoises, I received acceptance from Omaha’s Henry Doorly Zoo’s Genetics Department in 2015 to perform a genetics research experiment on each and every T. h. hermanni in my collection. The purpose of this DNA sampling was to compare them to those sampled by Perez et al. 2013 (the most comprehensive and fluently attainable study on this subject at the time) and to then be able to group them accordingly in the North American Regional Studbook for Testudo hermanni hermanni founded by myself and Steve Enders (Executive Director/Founder of theTurtleRoom.com). Proceeding with DNA sampling would furthermore allow us to either keep them within their assigned strains or remove them as the probability of the animals belonging to a said population in nature would be revealed. This solidification of known origin would thus lead to truly being able to keep the tortoises not only pure to their subspecies but to their lineage as well. In today’s world, this is of boundless importance as many chelonians continue to be mixed with all history being lost. We began with transporting the tortoises to our trusted veterinarian where we successfully extracted blood from each specimen using a phenol-chloroform isoamyl alcohol procedure. The samples were then sent off to the genetics department immediately. Following Perez’s sampling in 2013, the 12srRNA gene found within the mitochondrial DNA of a specimen was sequenced. Along with this, data was collected via nuclear markers. With individuals possessing an allele from each parent, this nuclear DNA allowed for examination of paternal factors and not just maternal. Four microsatellites were then amplified, originally found in the Galapagos tortoise (Chelonoidis nigra), and also used in the samples of T. h. hermanni, Perez et al. 2013. With these areas having a higher rate of transformation compared to other sections of a genome, greater variability between specimens or populations becomes apparent. However, in Perez’s original work, he used nine microsatellites. Five of these were excluded from our project due to the genetics lab at hand not having the primers yet to amplify those sectors of nuclear DNA. With the dataset available after amplification of the microsatellites, we could then compare to 330 genotypes of wild Hermann’s tortoises belonging to 22 known localities as discovered by Perez in 2013. These numbers are only a fraction of the entire wild population of Testudo hermanni but they are certainly helpful as well as greater than any other accessible data on the subject. Results enabled us to take a closer look at what we were dealing with as we had hoped. For example, our proposed Tuscan, Apulian and Calabrese specimens all aligned with the single Haplotype #5. “H5” is the most regular haplotype encountered in wild Hermann’s tortoise originating from mainland Italy. This strongly suggested that our tortoises did not derive from France because none of the French animals sampled by Perez carried H5. Probabilities were unveiled allowing us to keep tortoises within their proposed locales or remove them and place them in a more probable one. If the probability was less than 50%, a specimen was moved to the next most likely population within the studbook. Using the GeneClass ll population assignment analysis program ,Perez et al. 2013, these probabilities could be compared to Perez’s findings as well as to another keeper’s captive stock. Luckily, the majority of tortoises were already properly placed within their locales or strains in our North American Regional Studbook. Only a small few had to be reevaluated. Tortoises that were already in question based off phenotypic traits like color, size and other factors came to be the ones in question. Up until this point I could only rely on the physical appearance of an animal so it is encouraging that my assumptions based off this were actually quite accurate in their placement. This brings us to a very important subject worth covering which is the understanding of phenotypes. Most of the time we only have physical characteristics to go by when differentiating animals of any kind. It is extremely rare for genetic research to be conducted on captive specimens so relying on phenotypic traits is often paramount. With Hermann’s tortoises, particularly the western subspecies, locales have become somewhat understood by those serious about them. There certainly are factors that set them apart physically and these become quite useful when we do not have the privilege of looking at them internally. Still, it should not go without saying that without DNA, one cannot be absolutely sure of a tortoise’s lineage. This is because variation is present even within a designated population of animals. Nature always surprises us. We have been very fortunate to have been able to conduct such research and back up where our tortoises come from and so, they reside in groups which are isolated by locality. The majority of our collection is made of up tortoises from the Italian mainland, Italian islands and the Balearic Islands. Genetic results could of course not precisely place a tortoise in an exact region such as Crotone (city and comune in Calabria, Italy) for example, but they did allow for us to know the probability of a specimen as hailing from the Italian mainland or the islands. As per more in depth studies, we now know that T. h. hermanni is comprised of some unique genetic groupings so revealing probabilities helps us to maintain them accordingly. Once this was accomplished, we could then rely on phenotypic characteristics to narrow it down even further if need be. The animals were initially received as already being assigned to a designated local form and incredibly, the vast majority seemed to be fittingly grouped based on both genetics and phenotype. Thanks to DNA and history, I am able to describe to the best of my ability the traits that can be typically assigned to each locale/strain we maintain at Garden State Tortoise. The genetics and phenotypes of our specimens help to confirm the existing literature containing descriptions of known Testudo hermanni hermanni populations.
RECOGNITION OF STRAINS
If there is one thing that DNA research has taught us, it’s that the strains belonging to the western Hermann’s tortoise are different. In Italy, strong similarities between each local form offer us the option of simply grouping them altogether as one big cluster but segregation is the route we have chosen to go in our care. If anything, it allows for various unrelated bloodlines to be bred correspondingly. Even when using five less nuclear DNA markers than Perez et al. 2013, our geneticist was able to view probabilities of what populations the tortoises most likely belonged. At the very least, this allows for well-defined division between mainland and island populations which is already well noted in prior genetic research. Testudo hermanni hermanni is found across a very fragmented range in Italy with the islands Sicily and Sardinia, France with the island of Corsica and Spain including the Balearic Islands. There have been a few proposed groupings when trying to minimize the amount of strains into clusters to better understand genetics and how to manage populations. In 2016, population genetic testing showing five continental genetic groups and five insular genetic groups resulted in three evolutionary significant units concerning the western Hermann’s tortoise, Zenboudji et al. 2016. These clusters consist of continental (mainland Italy, southern France, Albera, Spain and northwest Minorca), insular (Sicily, Sardinia and Corsica) and a second insular (eastern Minorca). Robust genetic structure has enabled the recognition of the mentioned groups but they can also be broken up even further to justify conservation initiatives and particular strategies. Management units were then named based on geographic isolation and genetic uniqueness as follows: (1) Albera, Spain & Minorca1; (2) Varoise, France; (3) Peninsular Italy; (4) Sardinia & Sicily; (5) Corsica; and (6) Minorca2, Zenboudji et al. 2016. Aside from genetic revelations, each locality of tortoises varies even within the population when it comes to phenotypic attributes. Some follow a rather strict line of characteristics and can be recognized much easier than others while some exhibit extreme variation. Tortoises appearing as “carbon copies” of each other could be the repercussion of severe homogeny within a population. On the other hand, a wide mix of traits could be the result of the mixing of strains overtime through human interaction or it may simply just be that variation is nature’s way of “stirring the pot”. Big tortoises, little tortoises, some more colorful than others along with other descriptions confuse us on a daily basis when it comes to differentiation. Population testing has also shown us that rich genetic variation occurs more so on the islands home to Testudo hermanni hermanni and introgression with T. h. boettgeri may not happen at all whereas it does occur in some continental forms. When compared to that of mainland groups, the insular tortoises may help to shed some light on the continuing issue of other strains that are in danger of becoming extinct rather quickly such as the tortoises on the French side of the border near Albera which disappeared in the 1960s. Environmental threats to a species including demographic elements have been the most supreme factors for conservation historically but genetic properties are now attaining major recognition as a way to safeguard wild populations from extinction.
When dealing with tortoises in captivity, some believe that maintaining local forms as pure will have no benefit to wild populations. However, the bigger picture may prove otherwise as every positive course of action we take with our own animals is a step in the right direction for conservation, especially when dealing with an endangered taxa facing the immediate threat of bloodline pollution. In fact, maybe captive tortoises are deserving of much more attention and documentation in helping to unveil the genetic complexity of Hermann’s tortoises as a whole. Preserving the genetics of a species, subspecies, type locality, or form demonstrates discipline and a respect for nature. Using nature as a model is something I remain passionate about and this shows in nearly every aspect of how I keep T. h. hermanni. These groups have evolved over time to appear as they do today and I for one find that extremely interesting, intriguing and important. For these reasons and others I’ve maintained each known strain separated as they would be in their homelands. With the previously described genetic testing we accomplished in combination with known history, I will describe the strains of Testudo hermanni hermanni we maintain as follows:
Continental T. h. hermanni can be considered some of the most “textbook” or classic forms. Generally speaking, they exhibit a moderately domed carapace with 50% or more of it covered in black pigment however, very light colored individuals are not uncommon. A vibrant yellow ground color is bordered by jet black bars or blotches appearing nearly symmetrical. Some of the most stunning examples of these tortoises are found here. The quintessential keyhole symbol on the fifth vertebral scute is often well defined and easily noticeable. On the plastron, the pair of tell-tale longitudinal black bands running parallel along the midline are conspicuous and moderately thick. The gular scutes are commonly lacking any black pigment. The suture between the pectoral and humeral scutes usually dips down in a wide “U” which differs from some insular tortoises that may feature a straighter edged suture shaping to look more like a “V” or wavy line. The head is small with regular contours and is either dark or sometimes littered with light green to yellow markings on the top. The subocular spots on each side of the head may be faint or absent in older animals but on every single continental specimen in my collection, they are present to at least some degree. These tortoises may reach lengths of up to 14-15 cm for males and 15-18 cm for females. Overall shape is oval with minimal flaring of the rear marginal scutes on males. In comparison to the other continental groups such as France and Spain, Italy’s tortoises display more genetic diversity. It is imperative to understand that some of the forms that are now noted as accepted locales may actually be a mix from releases. This of course does not necessarily mean they are hybrids between the eastern and western subspecies but rather an introgression of documented forms already belonging to T. h. hermanni. Found in three distant regions but subjected to various localities on the Italian mainland, I will simply describe the main T. h. hermanni populations we care for here.
From central portions of Italy such as Tuscany down to Calabria in the far south, the western Hermann’s tortoise shows various levels of divergence. Tuscan specimens are sometimes pear shaped with an orange hue to the ground color of the shell. Animals in the eastern portion of this region may be larger and appear more colorful with a more noticeable subocular spot while those in the southern portion may be rounder and much darker. In elderly specimens the subocular may be lacking. A trait worth mentioning when discussing Tuscan specimens is the occasional lack of a central dark spot on the fourth vertebral scute of the carapace. Testudo hermanni hermanni typically features this spot but in tortoises native to Tuscany it may be missing on a small number. We’ve also noticed that the black stripes on the plastron are sometimes slightly separated where the pectoral scutes meet the humerals. Neither of these features should be associated with hybrids with Testudo hermanni boettgeri. DNA testing proved that even with these atypical traits, the tortoises were still pure to the western subspecies exclusively. Our Tuscan tortoises display more variation throughout their colonies than any other locale we maintain but they still easily fall into the western subspecies description. Sadly, introgressions between Testudo hermanni hermanni and Testudo hermanni boettgeri turn up throughout Tuscany from escaped pets or released individuals. However, even more have been documented in Varoise, France, Abruzzo, Italy and the Ebro Delta, Spain, Zenboudji et al. 2016. Described as “dirty” looking with mixed traits, drabber coloration and larger sizes, they have become an ongoing issue in parts within the western subspecies’ natural range. Nevertheless, perfectly pure tortoises do still exist, and it is imperative that they are preserved as such.
In Apulia, the two well-known populations are those of the Taranto Gulf which are small, darker colored specimens and then those deriving from Gargano which are a typical size for the western subspecies and have a flatter carapace with a pastel yellow. This influx of bright yellow in combination with jet black stripes and bars on the shell give the depiction of the abdomen of a bee. Many T. h. hermanni are rather striking from this area and I have clearly noted this in our own from here. In addition, these tortoises are quite “clean” in impression. The colors are bold, gular scutes are free of any dark pigment, subocular is usually prominent, nails are light yellow matching the skin, the keyhole symbol of the fifth vertebral scute is effortlessly recognizable and the plastral stripes are well defined extending from the humeral scutes to the anal scutes. These tortoises are, in my opinion, some of the most splendid examples of T. hermanni hermanni found anywhere.
In Calabria, some believe the tortoises feature a mixture of traits from continental and insular Italy. The only resemblance I have observed in some of our Calabrese animals is a reduced amount of black pigment on the carapace which is often encountered in insular specimens. Nonetheless, genetic results showed a higher probability (above 50%) of them being from continental Italy rather than insular so if there is any mixture, it’s only very weakly expressed, if at all. It has been said that the western Hermann’s tortoises of this region are the smallest, Wegehaupt et al 2009. Surely petite specimens (maybe some of the smallest) do occur in Calabria but regularly sized tortoises absolutely do as well. Our Calabrese T. h. hermanni are certainly on the smaller side but are by no means the smallest. Worth noting is the more lemon yellow ground color unlike the richer sometimes more orange tone of Tuscan animals.
The continental Italian forms we maintain produce on average, two to four eggs per clutch up to three times yearly. An occasional fourth clutch may occur. The clutches of Tuscan specimens may contain more eggs than Apulia or Calabria for example.
The Western Hermann’s tortoises occurring on islands throughout their Italian range exhibit an assortment of attributes. Due to the diversification of morphology, it was once thought that some of these populations may have been mixed with T.h. boettgeri. Their general appearance surfaced as atypical for the western subspecies to some thus leading to this assumption. Thanks to genetic population testing, we now know that these insular tortoises can all remain assigned to Testudo hermanni hermanni, and in actuality, hybridization with the Balkan form is quite rare, to be frank, it’s much rarer than on the continental areas. A number of classic attributes can be found throughout their Mediterranean Island range and with the phylogeographic link between Sicilian, Sardinian and some Corse populations already confirmed, it’s no surprise that they share a phenotypic conformity. Having maintained some of these strains myself, I cannot stress enough just how different they are from continental specimens. Even as neonates, they can be recognizable.
Sicily is home to three known populations which can be differentiated. Around the Madonie Mountains a particularly interesting strain of western Hermann’s tortoise occurs. I refer to these as the “Sicilian Spurred”. On each thigh, a tubercle or spur can be found much like that of Testudo graeca. They are in no way a hybrid with T. graeca but instead are a very unique form. I find them to be quite possibly the most idiosyncratic of the Testudo hermanni hermanni locales. These thigh spurs are sometimes even noticeable on juveniles and on adults they can be very prominent. This is not due to age as animals in their prime exhibit them well. Only some 28% of tortoises from the Madonie in our collection do not feature these spurs. They are also trapezoidal in shape. A flatter shell with the highest point situated more toward the back and flaring of the rear marginal scutes in both sexes help to give this overall impression. The carapace features a greenish-yellow ground color giving way to more fragmented black markings on each scute. Altogether lighter in coloration they can sometimes appear as almost fluorescent when wet from rain. The subocluar is usually large and noticeable from a distance on a narrow head with a sharply hooked beak. Small yellow flecks can be found around the nostrils with a greater concentration of them on the top of the head. The plastral stripes are well formed from the humeral scutes to the anal scutes. They may be broken at times where the pectorals meet the humerals but this is usually found on older specimens and probably from wear. On the inner sides of the gular scutes one or two black stripes or spots may be found. Referred to as the “gular mustache”, this trait is often assignable to insular Italian T. h. hermanni. Interestingly, this form is at times lacking one or both (rare) of the inguinal scutes. This is habitually associated with the Dalmatian tortoise (Testudo hermanni hercegovinensis) and not T. h. hermanni, yet these tortoises are genetically allocated to the western subspecies and nothing else at this time. Another facet commonly associated with insular animals which can also be found on these Sicilian Spurred tortoises is the shape of the second vertebral scute on the carapace. It tends to dip forward in a pronounced “U” shape whereas on continental tortoises this is less severe or routinely straight edged. Males of this strain are normal sized for the western subspecies but some of our females slightly surpass 18 cm.
Also found on Sicily are the populations of Nebrodi and Mount Etna. Nebrodi tortoises tend to be large, dark colored animals. Reports have been made of females surpassing 25 cm, a trait more commonly noted in some Sardinian and Corse (France) tortoises, with photos as proof. This locale may be much drabber in coloration with many having an influx of black but lighter specimens do exist. Thick plastral bands are present and the “gular mustache” may be as well. Thigh spurs have also been found on Nebrodi T. h. hermanni so it seems that this characteristic is commonplace for Sicilian examples in general.
In contrast to those found in Nebrodi, the Mount Etna western Hermann’s tortoises are small. Some consider them to be petite and the smallest of all forms with males barely making it to 13 cm and females not surpassing 15.5 cm. It’s possible that this relatively newly described form has simply not been studied enough and larger specimens are in existence. They are typically dark colored and rounded with all other assignable traits for the western subspecies usually present.
The island of Sardinia is home to some “giant” Testudo hermanni hermanni. It is absolutely not uncommon for females to regularly reach or even surpass 24 cm however, as variation would have it, there are normal sized animals too. With regards to our own Sardinian tortoises here, even our males are large at 16-17 cm. The majority of our females rest at around 21 cm. Northern animals are at times less vibrant with frayed markings and a slightly greenish hue to the ground color. Southern specimens are rather colorful with some being just as striking as those from Gargano in Apulia. Bright yellows, large sub ocular patches and high contrast are frequently encountered on Sardinian Giants. The “gular mustache” is once again existent on a number of individuals within this insular strain and so is the strongly “U” shaped first vertebral scute on the carapace. Similar to tortoises on Corsica, they feature a large, lower than usual carapace, Vetter et al. 2006. The head is similar to that of Madonie tortoises in that it is narrow with a recognizably hooked beak. Sardinian specimens bear a close resemblance overall to those of Sicily, particularly from the Madonie. Research does suggest the possibility of a localized extinction of the original tortoises on Sardinia and that the island was then recolonized by Sicilian animals, Zenboudji et al. 2016.
Our Italian insular tortoises produce on average, 3-5 eggs per clutch, two to three times yearly, but up to four clutches are not unheard of. Sardinian tortoises tend to have more eggs per clutch but they may also be smaller in size.
Testudo hermanni hermanni occurring on at least Mallorca have had a limited amount of time to evolve into how they are today. One must always keep in the forefront of their mind that variation persists but I find that some of these tortoises have a comparatively distinct look about them. Despite theories, their lineage is uncertain before being brought to these islands. Perhaps the south of France and continental Spain could be some of the areas they derive from. In my opinion they resemble them more than Italian specimens. The stripes running parallel along the mid suture of the plastron is one similarity. In Italian specimens the bands habitually remain completely separated at all times and while this is the case with really any T. h. hermanni, both continental France, Spain and Balearic Island tortoises feature one small trait worth disclosing that could set them apart. At the suture between the pectoral and abdominal scutes on either side of the midline, there is often a protruding spike of black pigment. These spikes point at each other and in rare cases may just barely meet. Sometimes the same two small spikes may be found where the humerals meet the pectorals as well. I do not witness this being as prominent on any of our multiple Italian tortoises. Whether or not this tool for recognition should be accepted is surely uncertain but I have been able to rely on it for my own tortoises. At this point I feel it wise to remind the reader that through the success of our own genetic testing, the morphological traits I choose to describe have their advantages since we know that these tortoises are correctly assigned to their origins. I can only hope that they may be of at least some assistance when differentiating this difficult taxon. The carapace of some Balearic Island tortoises is often raised in the anterior section creating a saddle shape profile view. The head is round and wide, colored dark on the top and the subocular spots vary with age. On juveniles, the spot may of course be much more observable, as is the case with any young T. h. hermanni. The snout is blunt in comparison to the more pointed and narrow one of the insular Italian specimens.
On Minorca, this blunt shaped snout is not always found. Consequently, it is beneficial to mention that Minorca is home to two conflicting populations. Both genetically and phenotypically, the animals in the northwest are believed to be descendants of continental tortoises while those in the southeastern portion descend from insular tortoises (Corsica, Sardinia & Sicily). In addition to this, around 50% of the representatives from Minorca are the result of introgressions between the two lineages found on the island, Zenboudji et al. 2016. The group maintained here is of the northwestern population (Minorca1), which is reported as originating from a now extinct continental population which was introduced to this island by man, Zenboudji et al. 2016. They exhibit all basic traits allocated to continental tortoises. Their typical size of around 13 cm for males and 16 cm for females along with general shape and pattern line up accordingly. The ground coloration on the carapace is slightly richer pointing to a bit of an orange hue and the nuchal scute is shortened or recessed. The recession gives way to a noticeable “V” shape above the neck as the marginal scutes on either side seem to protrude. An extremely intriguing observation within the Minorca group is the missing nuchal scute on hatchlings. Between 70 and 120 Testudo hermanni hermanni are hatched here yearly and this is the only form that exhibits this missing nuchal scute. Some 50% of babies are born missing it when ironically none of the adults lack it. In any case, it is unknown if these observations are isolated to my particular group of tortoises from Minorca or not, but they are certainly worthy of discussion.
We also maintain T. h. hermanni from Mallorca at Garden State Tortoise. This form was believed to be introduced some 3,000 years ago but remains found on the island were not precisely dated. Perhaps Mallorca is a form that is in dire need of study for a better understanding of how the Balearic Islands were colonized by the tortoises. The first time I was able to observe this form was in 2009. Immediately the drab colored head with dark green markings (or none at all), blunt snout and pale, lemon yellow ground color with varying degrees of contrast caught my eye. Every group I have come in contact with or viewed photos of seem to portray the same unmistakable look. The keyhole on every individual is well defined and not distorted and the plastral stripes are thick and unbroken extending from the humeral scutes to the anal scutes. Astonishingly, the nails of the front feet are sometimes black. This contrasts the normally light yellow colored nails which match the skin of most Testudo hermanni hermanni. Conceivably, this general appearance of Mallorcan individuals may be the result of the admixture of tortoises from various lineages over the course of many years. I still do find that both Mallorca and Minorca1 T. h. hermanni bear a closer resemblance to French or Spanish animals rather than Italian or insular specimens. In terms of size, our males do not exceed 13 cm and our females do not exceed 15.5 cm, fully grown. They are oval shaped with very minimal flaring of the rear marginal scutes on males.
Both Mallorcan and Minorcan forms produce on average, 1-3 eggs per clutch, twice yearly for us.
NOTES ON CAPTIVE CARE IN NJ
Although various chelonian species are maintained at Garden State Tortoise, those belonging to the genus Testudo have been a major focus and fare quite well here. Our beautiful autumn, cold winter, mild spring and warm to hot summer offer Hermann’s tortoises a chance to behave in a natural manner by following a yearly cycle.Various local forms of Testudo hermanni hermanni, Testudo hermanni boettgeri and Testudo hermanni hercegovinensis are kept in naturalistic outdoor enclosures as are all other Testudo tortoises we breed. They are only housed indoors occasionally in our tortoise building for illness, difficulty in rearing or sudden wake-ups from brumation. The sandy soil with gravel areas and the warm spot our property is located at in the coastal pinelands of southern New Jersey make for a wonderful environment to raise these tortoises.
During spring, summer and autumn, Hermann’s tortoises are maintained in large pens measuring at least 8 feet by 16 feet for no more than 10 adult individuals. Pressure treated wooden planks and posts are used to construct the retaining walls. Large, cedar based cold frames with polycarbonate paneling are situated at the back of each enclosure so the inhabitants can thermoregulate and prepare for brumation in autumn. The cold frames offer them a chance to warm up on less than desirable days throughout their active season as well. Inside the earth is loosened up and mixed with straw and leaves so digging is easily achieved. The pens are exclusively situated in the sunniest portion of the property and receive direct sunlight for nearly the entire day. Heather, spirea, hosta, yarrow and hibiscus along with fountain and maiden grasses are planted. Slightly raised areas of terrain and decor in the form of logs, brush and driftwood help to replicate a wild landscape. Both terra cotta saucers and 5 cm deep stainless steel dishes are provided for drinking and soaking which the tortoises use frequently. Wild, pesticide-free edibles are picked from the yard and surrounding area such as dandelion, catsear, thistle, lance leaf plantain, broad leaf plantain, purple dead nettle, clover, mulberry leaves, strawberry leaves and others. These items make up a large portion of their diet but Mazuri Tortoise Diet (original formula) and some store-bought greens are offered as well. Regardless of strain, the tortoises are active usually from April until November. In autumn, they slow down and begin to enter dormancy. Once winter has set in but before frigid temperatures take hold, the tortoises are removed from their cold frames where we have barricaded them since the end of autumn and placed into the crawl space under the house. They are moved at night so as to prevent any unnecessary awakening and kept in large totes filled with a sand/potting mix substrate with leaves and some straw. The crawl space maintains temperatures in the low 40s most of the time but does warm up to the 50s occasionally. The increase in temperature does not seem to cause any harm unless it persists. At that point, if temperatures are not hovering in the range we need them to in order to promote inactivity, some specimens may need to be overwintered inside our tortoise building. Even in these circumstances we have found that all T. h. hermanni will continue on with the rest of the annual cycle and remain in good health. Males are relentless in pursuing females during the spring and again in autumn but random matings can take place at any time throughout their active duration. Oviposition typically commences in spring between the months of April and June with later clutches being deposited in July. Very occasionally we receive clutches in early autumn. Eggs are removed from the earth and placed into artificial incubation. Deli cups with perforated holes are used for each individual clutch. No two strains of T. h. hermanni eggs are placed in the same container. This is to avoid the mixture of forms since neonates from some locales tend to look virtually identical. Vermiculite and water in a 1:1 ration by weight is used as an incubation medium. The clutches are incubated in two separate units. One is set to 82-86F to produce males and the other at 89.6-91F to produce females. Anything in between these ranges may result in a mix of sexes. The eggs begin to pip between 55 and 70 days with those subjected to higher temperatures hatching first. Hatchlings do vary in size with Mallorcan, Apulian and Calabrese forms being smaller. Sardinian, Sicilian, Tuscan and Minorcan babies are larger on average. Interestingly, both Sardinian and Sicilian neonates are usually more colorful and exhibit morphological traits normally associated with their insular lineages right at hatching. Even the gular mustache is visible at such a young stage of life. Once the yolk sac has been absorbed, the newly hatched tortoises are moved to rearing units. If the time of year is still unfavorable, they are raised inside for the time being. Rubbermaid containers or totes with a deep substrate of organic potting mix, sand and cypress mulch are used. Small terra cotta saucers offer water and full spectrum lighting is provided. Outdoors, they thrive in mini versions of the adult enclosures that are fully protected from predation. The hatchlings are fed the same diet as the adults.
There does not appear to be too many differences in the captive care of these T. h. hermanni forms here. All the adults exhibit a hardiness and are able to withstand the natural elements of southern New Jersey. The only real differences in terms of captive management seem to be isolated to reproduction. The Balearic Island forms in my collection produce particularly sensitive offspring and fertility is on average lower than Italian strains. They also produce less eggs per clutch and nest less frequently. Still, hatchlings do thrive and make it to adulthood. Above all, it is our Italian insular tortoises that produce the most with regards to clutch size and frequency.
There is much to be written about the genetic situation involving the western Hermann’s tortoise. Populations facing extinction are just a reminder of the sad state many chelonians face today. In conclusion, these literary works are not intended to sway an opinion or force one to believe in something they do not. They are written to promote awareness for the impending doom the animals will inevitably meet if action is not taken. Weak gene flow is associated with Testudo hermanni hermanni in its natural range and conducting genetic studies to find a way to avoid inbreeding depression and introgression between lineages ranks high for conservation measures. The management units (MU) proposed for conservation help to showcase the isolation of the populations and their demographic independence. In-situ work being done can then hopefully focus on strategies based on each MU. In captivity, my research of course has its limitations. Although the largest collection of Testudo hermanni hermanni in the United States may reside with us here, it is still merely a fraction of the entire wild population. Still, it was utterly flooring to be offered the chance to perform a genetic analysis of any kind on my own specimens. This is something one usually only dreams of. Our study may have been small in the grand scheme of things but it without a doubt unveiled some extremely interesting points.
On this site, I very passionately and enthusiastically give an account of what T. h. hermanni means to me. I also describe each form in my care thoroughly while keeping a close attachment to the fact that variation is paramount and should always be taken into consideration. In the United States, much more attention is given to chelonians from continents such as Asia and most pet turtles and tortoises belong to common types normally linked with the large pet trade. A tortoise such as the western Hermann’s is therefore sadly overlooked and certainly misunderstood. The purpose of my work and the construction of my website are in place to educate deeply because this kind of research regarding captive tortoises in my country is very rare. I truly admire the services accomplished by individuals around the world who have dedicated so much to the understanding of Testudo hermanni ssp in nature. I will never grow tired of hearing more about this taxon and in fact I am always learning more from you all. I can only hope that my small contributions to this subject will be of some interest and I am thankful for the overwhelming positive response so far. With evidence of Testudo hermanni hermanni being present in Western Europe since Plio-Pleistocene limit, we know we are dealing with an ancient animal well-worthy of attention. Today, we know that population genetic uniqueness found in each geographical region indicates strong genetic structure. Now endangered, the evolutionary legacy of the species must be represented through the utmost means of conservation, preservation and responsible captive propagation.
Director of Animal Husbandry, theTurtleRoom
Project Coordinator, njterrapin.org