Population and Thermal Ecology of Testudo hermanni hermanni in the Tolfa Mountains of Central Italy

Abstract Long-term ecological studies are important for understanding wild populations’ dynamics and processes and the actual factors that can determine their decline. Here, we report the results of a 28-years-long (1992–2019) monitoring of three distinct populations of a tortoise, Testudo hermanni, in Central Italy, with an emphasis on their population abundance trends and on the eventual variation in their habitat use across years and among the study areas. Samplings were conducted by Visual Encounter Survey (VES) methodology, and using a suite of statistical analyses including correlations and Generalized Linear Models analyses. Our data showed a statistically significant decline in tortoise sightings through time, and concurrently also a variation in habitat use by tortoises. In all the three study areas, we observed a significant increase of tortoise sighting frequency in the habitat type characterized by high (>taller than 200 cm) shrubby and wooded vegetation. Since our analyses revealed no significant change in the habitat type availability by year in each study area, we suggest that T. hermanni was increasingly selecting closed vegetation spots throughout the years. We hypothesize that this observed trend of shift in habitat selection could be due to lowering their body temperatures to prevent overheating. So, the selection of more covered spots would be a thermal ecology adaptive consequence of the ongoing global warming.

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Notes on the thermal ecology of Testudo hermanni hermanni in Menorca (Balearic Islands, Spain)

Amphibia-Reptilia ◽

10.1163/15685381-00003084 ◽

2017 ◽

Vol 38 (1) ◽

pp. 108-112

Author(s):

Zaida Ortega ◽

Abraham Mencía ◽

Valentín Pérez-Mellado

Keyword(s):

Substrate Temperature ◽

Sunlight Exposure ◽

Balearic Islands ◽

Late Spring ◽

Thermal Ecology ◽

Body Temperatures ◽

Air Temperatures ◽

Testudo Hermanni ◽

Substrate Temperatures ◽

Testudo Hermanni Hermanni

We studied the thermal ecology of Testudo hermanni hermanni in Menorca during late spring. We measured body temperatures of adult individuals, together with air and substrate temperatures at points of capture. Sunlight exposure (full sun, filtered sun, or shade) and type of substrate were also recorded. Body temperatures were similar between sexes (mean = 29.95°C) as were air temperatures between gender capture sites (mean = 28.33°C). Conversely, females were found in areas with a higher substrate temperature (31.60°C) than males were (29.15°C). Moreover, the correlation between body and air temperatures was stronger than it was between body and substrate temperatures, as found in other populations of this species. The tortoises were usually found in full sun, and the proportion of animals found in each sunlight category was similar between sexes. Our results contribute to the knowledge of the thermal ecology of the western Hermann’s tortoise.

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Seasonal Changes in the Diet of Testudo hermanni hermanni in Central Italy

Herpetologica ◽

10.1655/herpetologica-d-10-00064.1 ◽

2011 ◽

Vol 67 (3) ◽

pp. 236-249 ◽

Cited By ~ 9

Author(s):

Silvia Del Vecchio ◽

Russell L. Burke ◽

Lorenzo Rugiero ◽

Massimo Capula ◽

Luca Luiselli

Keyword(s):

Seasonal Changes ◽

Central Italy ◽

Testudo Hermanni ◽

Testudo Hermanni Hermanni

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Bioelectric potential profiles in the bladder mucosa of the tortoise Testudo hermanni hermanni Gmelin

Life Sciences ◽

10.1016/0024-3205(71)90129-9 ◽

1971 ◽

Vol 10 (6) ◽

pp. 309-316 ◽

Cited By ~ 2

Author(s):

M. Gilles-Baillien ◽

E. Schoffeniels

Keyword(s):

Bioelectric Potential ◽

Bladder Mucosa ◽

Testudo Hermanni ◽

Testudo Hermanni Hermanni

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Thermal ecology and reproductive cyclicity of the snake Natrix tessellata in south-eastern Austria and central Italy: a comparative study

Amphibia-Reptilia ◽

10.1163/156853897x00431 ◽

1997 ◽

Vol 18 (4) ◽

pp. 383-396 ◽

Cited By ~ 5

Author(s):

Petra Zimmermann ◽

Luca Luiselli

Keyword(s):

Body Temperature ◽

Average Length ◽

Central Italy ◽

Thermal Ecology ◽

Mean Body Temperature ◽

Widespread Species ◽

South Eastern ◽

Eastern Austria ◽

Reproductive Females ◽

Two Populations

AbstractAspects of thermal ecology and reproductive cyclicity are compared in two populations of the dice snake (Natrix tessellata), a semi-aquatic natricine species widely distributed across Europe. One population was studied near Leibnitz, Styria (south-eastern Austria), and the other one was studied in the Mounts of Tolfa near Rome (Latium, central Italy). The climate was strongly colder in the Austrian than in the Italian site. Snakes of both populations were similar in various traits, including average body temperature, higher mean body temperature of gravid than non-gravid individuals, significantly higher substratum temperatures selected by gravid than by non-gravid individuals, trends of relationships between body, air and substratum temperatures, average length of reproductive females, and average preparturition mass of reproductive females. However, Austrian snakes were found in water significantly less often than their Italian conspecifics (although in both populations nearly all individuals occurred close to water bodies), and showed a lower frequency of reproduction (biannual rather than annual) than Italian ones. The presented data are discussed in the light of suboptimal occupation of the colder area by Austrian snakes, and conservative rigidity of natural history and ecological traits of such a widespread species as N. tessellata.

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