It spends most of its time in a burrow, in leaf litter or under bark and logs. Diet Adult marbled salamanders eat invertebrates including earthworms, slugs, snails, centipedes and a variety of insects. Larvae eat zooplankton. As they grow larger, they will eat tadpoles, insects and other salamander larvae. Life Cycle The marbled salamander breeds from September to October in the northern part of its range and from October to December in the southern part of its range.
The marbled salamander mates and lays its eggs on land. The female lays eggs, one at a time, in a depression under a log or in a clump of vegetation that will fill with water when it rains. Eggs hatch as soon as they are covered with water, but may delay until spring if rainfall is insufficient to cover them. Larvae are about 0. Their lifespan is about four years. Male marbled salamanders breed near water. They emerge during winter rains and enter shallow pools to deposit sperm packets. The females arrive later, pick up the packets and fertilize their eggs internally, storing them until it is time to lay their clutch group of eggs.
The females select a point between the shallowest and deepest area of the ponds. Then they lay their eggs one at a time in a shallow depression under vegetation, encircling the eggs until the depression fills with water from spring rains. This behavior is called brooding the eggs. Young are generally brown to black with light spots or mottling dorsally on top and laterally on sides. Marbled salamanders darken as they mature. Individuals of some Ambystoma species may return to their summer home range from the previous year Semlitsch, b , and this may be true in marbled salamanders P.
The orientation behavior exhibited by Marbled Salamanders is a necessary precursor to territoriality, although territoriality itself has not been documented. Despite reports that Marbled Salamanders can occur in unusually dry habitats e. Dehydrated salamanders incur substantial metabolic costs, however Sherman and Stadlen, To minimize water loss, Marbled Salamanders likely avoid desiccating conditions; as soils dry in late summer, animals may retreat to deeper burrows P.
Rehydration rates were faster in Marbled Salamanders than in more aquatic species, and faster in severely dehydrated animals than in less dehydrated individuals Spight, a.
Heat stress - Larvae of Marbled Salamanders have less resistance to high temperatures i. Smaller adult salamanders reach their CTM faster than larger adults Hutchison, The possible relationship between CTM in eggs, larvae, and adults, and geographic distribution or timing of breeding sensu Gatz, is unknown. Water stress - In general, post-metamorphic Marbled Salamanders do not appear to respond well to prolonged immersion in water personal observation. Under anoxic conditions, larvae may exhibit anaerobic glycolysis Weigmann and Altig, Metabolic rate.
Lunged salamanders, including Marbled Salamanders, increase levels of oxygen consumption with increasing body size Whitford and Hutchison, ; Krenz, Resting metabolic rate is positively correlated with multi-locus heterozygosity Krenz, ; more heterozygous females with higher metabolic demands allocated less energy to their clutches of eggs Krenz, Seasonal Migrations - Restricted to times of breeding adults; see "Breeding migrations" above and following metamorphosis juvenile; see "Features of metamorphosis" above.
Post-metamorphic dispersal is restricted to rainy nights. The period between metamorphosis and dispersal may be several weeks or more depending on occurrence of nighttime rainfall and is likely a period of high mortality for juveniles personal observation. Hibernation in the southern portions of their range is unknown. Larval Marbled Salamanders will feed on other amphibian eggs and larvae Walters, , including Ambystoma larvae.
Spotted Salamander larvae may be more susceptible than mole salamander larvae to this predation due to increased use of refugia by Mole Salamanders Walls, Consequently, although larval Marbled Salamanders are often predators, they may also be competitors Wilbur, ; Stenhouse, b; Cortwright, ; Semlitsch et al.
Predation by Marbled Salamander larvae may substantially affect community dynamics Cortwright and Nelson, ; Morin, ; Boone et al. Juvenile Marbled Salamanders that were tested under laboratory conditions with conspecifics and with juvenile Mole Salamanders did not show any overt aggression, perhaps indicating that such behavioral interactions are not important for juveniles Smyers et al.
Additional experiments with juvenile Spotted Salamanders indicated that juvenile Marbled Salamanders may defend burrow space by excluding heterospecific salamanders Smyers et al. Males tend to mature at an earlier age than females Scott, ; Pechmann, ; average age at first reproduction for males is 2. The range of age at first reproduction for both sexes is 1—7 yr. Longevity - Survival to first reproduction can be low and is influenced by size at metamorphosis.
Variation in body size at metamorphosis is coupled with variation in lipid stores ranging from 2— Small, lean animals may suffer the highest mortality immediately following metamorphosis Scott, Males may exhibit higher survivorship than females due to their earlier age at first reproduction Scott, Maximum lifespan in the field appears to be 8—10 yr Graham, ; Taylor and Scott, Feeding Behavior.
Stomach contents of juveniles and adults include millipedes, centipedes, spiders, insects, and snails Dundee and Rossman, ; arthropods, annelids, and mollusks Smith, Eggs - Eggs may be preyed upon by beetles, salamanders, frogs Noble and Brady, , and possibly a millipede species Uroblaniulus jerseyi; Mitchell et al. Larvae - Larvae are palatable to fishes Kats et al. Larval Marbled Salamanders are prey for numerous species, especially invertebrates including dragonfly naiads Odonata , spiders Arachnida , dytiscid beetle larvae and adults Coleoptera , and giant water bugs Bellostomatidae.
Often the tails are not eaten personal observation. Newly metamorphosed animals may be susceptible to mammalian predators as well as some snakes; one Banded Watersnake Nerodia fasciata had eaten 34 recently metamorphosed Marbled Salamanders unpublished data. Liner reported ingestion of two recently metamorphosed Marbled Salamanders by a Western Ribbonsnake Thamnophis proximus.
Eggs - Protection of eggs from predators is possibly one function of nest-brooding by females Petranka, Larvae - Limited diurnal movements and hiding in benthic debris may reduce predation Hassinger et al. Hatchlings and small larvae may use the sun as a cue to orient toward deep water Tomson and Ferguson, Larvae do not change behavior i. Such behaviors may draw the attacks toward the tail, which has concentrations of granular glands on dorsum that produce noxious secretions.
Adults are unpalatable to common ribbon snakes Thamnophis s. Mills, personal communication. Secretions generally confer protection from a single attack by shrews Brodie et al. Secretions in marbled salamanders are reduced after multiple attacks by shrews, resulting in increased vulnerability DiGiovanni and Brodie, Diseases - An aquatic fungus Saprolegnia sp.
Marbled salamanders have been used in toxicological tests of hydrazine compounds Slonim, , beryllium sulfate Slonim and Ray, , pesticides Hall and Swineford, , and motor oil Lefcourt et al. Parasites - Rankin reported the following parasites from Marbled Salamander larvae in North Carolina: Protozoa—Cryptobia borreli, Eutrichomastix batrachorum, Hexamitus intestinalis, Prowazekella longifilis, Tritrichomonas augusta; Trematoda—Diplostomulum ambystomae; Acanthocephala—Acanthocephalus acutulus.
Rankin reported the following parasites from Marbled Salamander adults in the same populations: Protozoa—Cryptobia borreli, Cytamoeba bacterifera, Eimeria ranarum, Eutrichomastix batrachorum, Haptophyra michiganensis, Hexamastix batrachorum, Hexamitus intestinalis, Prowazekella longifilis, Tritrichomonas augusta; Trematoda—Brachycoelium hospitale, Diplostomulum ambystomae; Gorgoderina bilobata, Megalodiscus temperatus, Plagitura sp.
The trematode Brachycoelium ambystomae was reported from Marbled Salamanders by Couch , and an unidentified immature trematode by Malewitz In each of these states, permits are required for any activity involving Marbled Salamanders. Given the reliance of Marbled Salamanders on small isolated seasonal wetlands and intact forested floodplain habitats, their abundance presumably has declined as wetland habitats have been destroyed Petranka, Further loss of small wetlands such as Carolina bays will likely be accelerated by the U.
As isolated wetland habitats disappear and remaining wetlands become increasingly separated, the cumulative impact on amphibian populations such as Marbled Salamanders will likely be substantial and perhaps non-linear, as elimination of remaining wetlands results in proportionally larger and larger effects on pond-breeding amphibian populations.
For conservation efforts to succeed it will also be critical that the wetland ecosystem be viewed not solely as the wetland itself, but also the adjacent terrestrial habitat that is essential to the persistence of pond-breeding amphibians Scott, ; Gibbons, Virginia Herpetological Society.
Average Length: 3. Arrangement 1 Sub-arrangement A - Eggs grouped singles, weakly adherent eggs, guarded by parent at semi terrestrial sites before autumnal rains fill pools; jelly layers tough and resilient. Bishop, S.
0コメント