I recently visited a number of Salamandra salamandra terrestris deposition sites in the Limousine/Berry region of central France. S. s. terrestris were the dominant caudate in the area, utilising a full range of small water bodies for larval deposition. Water bodies considered suitable ranged from very small puddles (12 inches x 6 inches) to large permanent pools (20ft diameter). Sites were shared with other amphibians; Rana esculenta, Lissotriton helveticus, Rana dalmatina, Rana temporaria, Rana lessonae, Bufo bufo, Hyla arborea and Bombina variegata. S. s. terrestris tolerated the widest range of water bodies and were the only species found in small, shallow puddles. Other amphibian species all favoured larger permanent water.
Pool in livestock field:
Forest edge pool:
Track-side ditches:
Shallow puddles containing larvae (note helpful wife searching for next available log to flip).
By late May S. s. terrestris larvae in this region are between 5-7cm in length and nearing metamorphosis. Larger specimens already display black and yellow pigments with reduced gills. Larval size varied between sites. The largest and nearest to metamorphosis were found in permanent water bodies with a rich diversity of aquatic invertebrates and hence the greatest food supply. The smallest/thinnest larvae were found in shallow temporary water bodies presumably for the opposite reason – no permanent aquatic prey items were evident.
Advanced larvae found in permanent pools:
Some starting to show colour pigments:
Typical net haul:
Adult S. s. terrestris are particularly elusive at this time of year and as the summer approaches hide themselves deep into the forest floor, under rotting logs and bases of trees etc. Nocturnal searches around deposition sites, even on wet days proved fruitless. Adults were only found by turning logs. Near roadside sites dead adults were often seen flattened on the tarmac. Day time air temperatures ranged from 22C – 34C, although much cooler on the forest floor (sadly the only thermometer I had was on my car). Evening temperatures seen ranged between 11C – 19C.
In forest habitats small shallow puddles (created by tyre tracks and even footprints) were utilized. Anything over 1cm in depth and out of full sunlight was considered appropriate. Slow running, shallow water was also used.
Adult S.s.terrestris:
Forest habitat:
Larval density varied between pools; some containing single larva and others containing 100+. Pools closest to the forest edge tended to be the most densely populated, pools in open spaces with little or no surrounding vegetation were least popular. My initial thought was that larvae in such shallow pools must surely die as water evaporated. None were particularly young however and some quick experiments showed that if removed from the water their well developed limbs were strong enough to carry them quite a distance at considerable speed. It is conceivable to me that advanced larvae can make short journeys to neighbouring puddles rather than perish. This is just supposition though. Recent rainfall would suggest that the small pools were not created by evaporation of larger pools. Larvae were found in puddles containing around half a litre of water, not much more than a cup full – either they were deposited there or have somehow moved there during the course of their development.
Tiny puddle (foot print size) containing single larvae:
The larva from above puddle:
Count the larvae - example of larval density. This water is approximately 1cm deep.
Whilst population size, based on larval numbers, was far greater in forest habitats, S. s. terrestris was also found in good numbers on agricultural lands and within the built environment. Livestock pools, water troughs and roadside drainage ditches were all used for larval deposition often within close proximity of human habitation. Some roadside water bodies had thick films of oil sitting on them - pretty undesirable for amphibians, and yet the larvae still appeared to be thriving.
Livestock trough:
Larva within:
Near roadside sites roadkill was often observed:
In deeper water bodies S. s. terrestris close to metamorphosis were observed to float at the water surface, possibly due to gill reduction (?). It appeared to me that they become somewhat more buoyant and struggled to dive when frightened.
Some other animals sharing S.s.terrestris habitat:-
Podarcis muralis - Wall lizard
Bufo bufo - Common toad
Rana temporaria - Common frog
Juvenile Rana esculenta - edible frog
Female Lissotriton helveticus - Palmate newt
Same female with S.s.terrestris larvae
Male Lissotriton helveticus:
Larval Lissotriton helveticus
Tadpoles - not sure of species
This one was a giant:
Anguis fragilis - Slow worm
And finally the patient herper himself:
Pool in livestock field:
Forest edge pool:
Track-side ditches:
Shallow puddles containing larvae (note helpful wife searching for next available log to flip).
By late May S. s. terrestris larvae in this region are between 5-7cm in length and nearing metamorphosis. Larger specimens already display black and yellow pigments with reduced gills. Larval size varied between sites. The largest and nearest to metamorphosis were found in permanent water bodies with a rich diversity of aquatic invertebrates and hence the greatest food supply. The smallest/thinnest larvae were found in shallow temporary water bodies presumably for the opposite reason – no permanent aquatic prey items were evident.
Advanced larvae found in permanent pools:
Some starting to show colour pigments:
Typical net haul:
Adult S. s. terrestris are particularly elusive at this time of year and as the summer approaches hide themselves deep into the forest floor, under rotting logs and bases of trees etc. Nocturnal searches around deposition sites, even on wet days proved fruitless. Adults were only found by turning logs. Near roadside sites dead adults were often seen flattened on the tarmac. Day time air temperatures ranged from 22C – 34C, although much cooler on the forest floor (sadly the only thermometer I had was on my car). Evening temperatures seen ranged between 11C – 19C.
In forest habitats small shallow puddles (created by tyre tracks and even footprints) were utilized. Anything over 1cm in depth and out of full sunlight was considered appropriate. Slow running, shallow water was also used.
Adult S.s.terrestris:
Forest habitat:
Larval density varied between pools; some containing single larva and others containing 100+. Pools closest to the forest edge tended to be the most densely populated, pools in open spaces with little or no surrounding vegetation were least popular. My initial thought was that larvae in such shallow pools must surely die as water evaporated. None were particularly young however and some quick experiments showed that if removed from the water their well developed limbs were strong enough to carry them quite a distance at considerable speed. It is conceivable to me that advanced larvae can make short journeys to neighbouring puddles rather than perish. This is just supposition though. Recent rainfall would suggest that the small pools were not created by evaporation of larger pools. Larvae were found in puddles containing around half a litre of water, not much more than a cup full – either they were deposited there or have somehow moved there during the course of their development.
Tiny puddle (foot print size) containing single larvae:
The larva from above puddle:
Count the larvae - example of larval density. This water is approximately 1cm deep.
Whilst population size, based on larval numbers, was far greater in forest habitats, S. s. terrestris was also found in good numbers on agricultural lands and within the built environment. Livestock pools, water troughs and roadside drainage ditches were all used for larval deposition often within close proximity of human habitation. Some roadside water bodies had thick films of oil sitting on them - pretty undesirable for amphibians, and yet the larvae still appeared to be thriving.
Livestock trough:
Larva within:
Near roadside sites roadkill was often observed:
In deeper water bodies S. s. terrestris close to metamorphosis were observed to float at the water surface, possibly due to gill reduction (?). It appeared to me that they become somewhat more buoyant and struggled to dive when frightened.
Some other animals sharing S.s.terrestris habitat:-
Podarcis muralis - Wall lizard
Bufo bufo - Common toad
Rana temporaria - Common frog
Juvenile Rana esculenta - edible frog
Female Lissotriton helveticus - Palmate newt
Same female with S.s.terrestris larvae
Male Lissotriton helveticus:
Larval Lissotriton helveticus
Tadpoles - not sure of species
This one was a giant:
Anguis fragilis - Slow worm
And finally the patient herper himself: