Salamanders are carnivores that aren’t very picky with what they eat. Their generalist diet means salamanders can find food in the variety of habitats they live in
However, despite their diverse diets, salamanders still sometimes find themselves in environments where food sources are scarce. So, how long can a salamander go without eating?
Generally, healthy adult salamanders can go for 3- 4 weeks without food, provided they were well-fed before the period of starvation. Juvenile salamanders and larvae can not survive long without food as they are still growing and have higher energy needs.
However, during hibernation, adult salamanders can go for several months without food.
How long a salamander can survive without food is influenced by several factors, including its health, stage of development, ambient temperatures, and the time of year.
Salamander Larvae Can Not Go Long Without Food
Salamanders begin their lives as tiny embryos inside eggs.
At this stage, the embryos get all their nutrition from the yolk of the egg. It contains enough nutrients to sustain them until they are ready to hatch as larvae – In about 2 -4 weeks, depending on the species.
When the larvae hatch, they have well-developed eyes, mouths, external gills, and broad tails – and will feeding on small aquatic invertebrates.
Salamander larvae develop very rapidly and need to eat very often.
Since the larvae have high energy demands, they can only go without food for about 24 hours to a few days.
Under ideal conditions, salamander larvae need to eat several times a day and have food available at all times.
Juvenile Salamanders Cannot Go Long Without Food
After about 2 to 5 months (depending on the species), the larvae will slowly begin transforming into juveniles through a process known as metamorphosis, which prepares them for a life on land.
During this process,
- Their gills shorten (and are eventually absorbed into the head)
- They develop lungs for breathing air (not all species)
- Their flat tail will thicken and become more rounded
Once this process is fully complete, the larvae will leave the pond to live on land. At this point, their diet will shift away from aquatic prey and toward terrestrial prey.
These juvenile salamanders will grow into adult salamanders over time.
Since Juvenile salamanders are still growing, they have high energy demands and can not survive long without food.
As a generalization, most juvenile salamanders can only go for 3 days to a week without food.
Ideally, juvenile salamanders need to eat once daily or every other day.
Adult Salamanders Can Go 3 – 4 Weeks Without Food
In general, adult salamanders can go for 3 – 4 weeks without food if they are healthy and were previously well-fed before this period.
However, during hibernation (brumation), adult salamanders can survive for several months without food.
This is because their metabolic rate is drastically reduced to a point where all their energy needs can be met without any food intake for extended periods.
It’s important to note that even outside brumation, the ambient temperature will influence how often a salamander needs to eat.
In most cases, salamanders can go without food for longer periods when the ambient temperatures are low.
At warmer temperatures, they will need to eat more frequently to avoid starvation (more information on that is below).
How Long Frogs Can Go Without Food Is Mainly Influenced by 7 Factors
1. Species
Salamanders of some species are genetically programed to be able survive without food for longer periods than those of other species.
Salamanders that are adapted to live in harsh environments with little food can usually go without good for longer periods than other species.
2. Stage of Development
Most salamanders (not all) develop in 4 distinct life stages: Egg, larvae, Juvenile and Adult.
During these different stages of their life cycle, salamanders will have different energy needs.
Salamander larvae grow rapidly and need to eat a lot of food to support their development. Under ideal conditions, larvae need to eat daily and have food available at all times.
Juvenile salamanders, while more developed than the larvae, are still growing and also have high energy demands and need to eat frequently, ideally once daily or every other day.
Adult salamanders are fully developed and do not need as much nourishment as larvae or juveniles.
Most healthy adult salamanders can safely go for 2 weeks, and even as as long a 3 or 4 weeks without food, provided they were well fed before this period.
However, in most cases, adult salamanders should ideally eat at least twice a week to maintain optimal health.
3. The Salamanders Health
Health also plays a role in how long a particular salamander can go without food.
Healthy salamanders can generally survive for longer periods without food than weak or sickly individuals.
For example, a salamander with a broken leg may require more energy than a healthy individual.
4. How Well Fed the Salamander Was Before the Starvation Period
A salamander that was well nourished before the period of starvation may be able to survive without food for longer than an individual that was poorly nourished.
This is because the well-nourished salamander would have built up more energy reserves enabling it to survive longer.
5. Environmental Conditions
The environmental conditions can impact how long a salamander survives without food.
Salamanders may be able to survive for longer periods without food in clean habitats that are free of predators and have plenty of water.
Generally, salamanders will be able to preserve their energy if they do not have to escape predators, or travel long distances to find water, or suitable hiding spots.
6. Temperature
Like all amphibians, salamanders are cold-blooded (ectothermic) animals.
This means they cannot internally regulate their body temperature. Instead, their body temperature changes with the temperature in their surroundings.
In other, their environment is the main influence on their body temperature.
For example, a salamander in an environment with an ambient temperature of 30°C (86°F) has a body temperature very close to 30°C. In an environment with a temperature of 15°C (59°F), the body temperature of the same salamander is around 15°C.
Being ectothermic means salamanders will have a varied rate of metabolism, depending on the temperature.
Warmer water temperatures increase metabolic rates. This means salamanders have to eat more often to meet all their energy needs.
On the opposite end, cooler temperatures allow salamanders to conserve oxygen. This extends the time they can go without food.
7. Time of the Year
- Winter
During the winter, salamanders enter a state of hibernation (brumation) to protect themselves from freezing temperatures in the winter.
During hibernation, their metabolic rates fall and frogs can survive for several months without food.
That said, salamanders need to “bulk up” to prepare for hibernation,
During this period, they will start to eat more than normal to put on good body weight and create energy reserves to maintain important bodily functions during hibernation.
If a salamander does not adequately prepare for hibernation and create sufficient energy reserves, it may not make it through the winter.
- Summer
Freezing temperatures aren’t the only thing salamanders have to worry about.
High summer temperatures are just as undesirable as the cold. This is where estivation (also spelled as aestivation) comes in.
Estivation is when an animal enters a state of dormancy to conserve energy when the environmental conditions are very hot and dry.
The breathing rate, heart rate, and general metabolic rate all decrease, just as they do in hibernation. Think of it as some sort of summer hibernation.
If the summer weather gets too harsh, salamanders will find a cool moist place and estivate as they wait for the rain to come and the temperatures to drop.
During estivation, salamanders can survive for several weeks without food.
If the rain comes, but the temperatures remain high, salamanders will not emerge until the temperatures are cooler.
The Salamander That Can Survive a Decade Without Food
A European cave-dwelling salamander called the olm (Proteus anguinus) is known to be able to survive for up to 10 years without food.
Fun fact: Olms can live for over 100 years, which makes them longest-lived amphibians. They also reach adulthood after 12 years, making them one of the slowest growing salamanders.
How can they go that long without food? Simply put, they consume large amounts of food at once and store large deposits of nutrients in their bodies. They can also drastically reduce their activity and metabolism when food is scarce.
Scientists from Eötvös Loránd University in Budapest studied Olms living within a limestone cave in eastern Bosnia-Herzegovina.
The researchers found that over 8 years, many of the animals didn’t seem to move more than 10 meters (33 feet) from their original spot.
One olm even appeared to stay in roughly the same spot for seven years!
These salamanders do not have any predators in the underground cravens they live in. Moving very little enables them to conserve as much energy as possible.
Olms live in dark underground caves with little available food. Their extreme resistance to long-term starvation is an adaptation that is necessary for their survival. In severe cases, these animals can also reabsorb their own tissues.
How Long Can Salamanders Go Without Water?
In general, most highly aquatic salamanders can only survive for a few hours without water, outside of hibernation or estivation.
Terrestrial salamanders, on the other hand, can survive without water from 24 hours to a few days, depending on the species, and environmental conditions.
That said, some salamander species, such as the Red-backed salamander (Plethodon cinereus) are entirely land-dwelling and do not need standing water of any kind.
These salamanders usually will not go to water, even to breed. They re-hydrate entirely by absorbing moisture from moist soil, or any other moist material, such as damp leaf litter.
This adaption allows Red-backed salamanders to live in fragmented forests, and even in urban areas – without the limitation of a direct dependency on water.
Sources:
Balázs, G., Lewarne, B. and Herczeg, G. (2020), Extreme site fidelity of the olm (Proteus anguinus) revealed by a long-term capture–mark–recapture study. J Zool, 311: 99-105. https://doi.org/10.1111/jzo.12760
Bulog, B. (1994). “Dve desetletji funkcionalno-morfoloških raziskav pri močerilu (Proteus anguinus, Amphibia, Caudata)” [Two decades of functional-morphological research on the olm (Proteus anguinus, Amphibia, Caudata)]. Acta Carsologica.