How insects survive the long, cold winter: University of Delaware
How ants winter — food, diapause, hibernation
- 1 How ants winter — food, diapause, hibernation
- 2 Ant Hibernation (Diapause)
- 3 Do my ants require hibernation?
- 4 How Do I Hibernate My Ants?
- 5 When Is Hibernation Over?
- 6 What Happens If I Don’t Hibernate My Ant Colony?
- 7 Difference Between Diapause and Hibernation
- 8 Key Difference – Diapause vs Hibernation
- 9 What is Diapause?
- 10 What is Hibernation?
- 11 What are the Similarities Between Diapause and Hibernation?
- 12 What is the Difference Between Diapause and Hibernation?
- 13 Summary – Diapause vs Hibernation
- 14 Do Ants Hibernate While It’s Cold?
- 15 Video of the Day
- 16 No Lazy Ants
- 17 Hibernation, Not Starvation
- 18 Warmth in Numbers
- 19 Emergence
- 20 Hibernation? Diapause?
- 21 Hibernation? Diapause?
9:12 a.m., Feb. 3, 2011—-Baby, it’s cold outside. Time to put another log on the fire, wrap up in a thick sweater, or make a steaming mug of tea. These human adaptations to cold weather are quick, easy and get the job done. Even more effective, of course, is the central heating that is ubiquitous in our homes, offices and schools.
It takes a lot more effort for other mammals, birds and insects to make the necessary adaptations to survive harsh weather. Next week, we’ll look at animal and bird strategies; today we’ll see how insects make it through the winter.
In many species, insects adapt to the cold by dying off; it’s the larval stage of the species that goes through winter. Insects that do over-winter as adults usually enter a hibernation-like state called diapause.
“Insects don’t technically hibernate in winter but many go into diapause, a dormant state that allows them to withstand cold temperatures,” says Brian Kunkel, a UD Cooperative Extension entomologist.
The mourning cloak butterfly exists in a type of diapause called freeze susceptible. It avoids freezing in much the way that car owners do — by adding anti-freeze. This butterfly replaces the water in its body with antifreeze compounds — called cryoprotectants — which supercool its bodily fluids and tissues.
The other form of diapause, called freeze tolerant, is used infrequently by North American insects but is a common strategy of Southern Hemisphere insects. In this type of diapause, the insect freezes its bodily fluids.
Not all insects go into diapause in winter. A few, like the stonefly and mayfly, can be seen out and about in their adult form. The best time to look for stoneflies is after a snowfall — these small dark critters are much easier to spot in the snow.
The social insects take a middle-of-the-road approach to winter. They don’t enter diapause, like many butterflies, but they’re not bounding about, full of pep, like stoneflies. Social insects that live through winter in Delaware include honeybees, termites and a number of different ants.
Many of the social insects, including ants, consolidate their living quarters during the winter, says Deborah Delaney, an assistant professor in the Department of Entomology and Wildlife Ecology in UD’s College of Agriculture and Natural Resources. In late fall they move deeper into their nests and close up the exit with soil, leaves and other organic materials.
Honeybees slow down in winter and stick close to the hive. The focus is on eating and huddling close to each other on cold days, notes Delaney.
When the hive temperature drops below 64 degrees, honeybees cluster together into a carefully organized, compact ball. The interior bees generate warmth by vibrating their wing muscles. The outer bees are motionless, acting as an insulation layer. The colder the temperature outside, the tighter the cluster. A single bee can increase heat production 25-fold.
The honeybees take turns enjoying the warmth in the middle of the huddle and then move to the outside. Not surprisingly, the queen bee reigns supreme in the middle and never takes a turn on the outskirts of the huddle.
Despite huddling and other strategies, winter takes a toll on honeybees, says Delaney. Hives that may have had a peak of 60,000 bees in the summer may diminish to 20,000 bees by mid-winter. Some hives are totally lost, due to insufficient food or other factors.
Worker honeybees toiled long hours in the fall, collecting nectar to feed and maintain the colony until spring. If their work wasn’t adequate, there is nothing they — or Delaney — can do about it now, in the depths of winter.
Nonetheless, Delaney checks on the hives at UD’s Apiary about two to three times a week this time of year. “I hold my ear to each hive and if I hear buzzing inside, I know everything is good,” she says.
“The hives are kind of like my fourth child,” admits Delaney, who is the mother of three small children.
Article by Margo McDonough
Photo by Danielle Quigley
Ant Hibernation (Diapause)
As ant keepers, we frequently observe our small inhabitants looking for changes and just inspecting them to ensure the health and growth of the colony. A frequent observation that most ant-keepers notice during winter months their colonies activity starts to slow down, or the amount of new brood growth appears to have slowed or egg-laying has even ended. This is generally because you ants have an internal biological clock and it has triggered their hibernation period.
Do my ants require hibernation?
In colonies that are native to areas that have cold winters, your ants will likely require hibernation. In a natural setting winter is a yearly event that gives the colony a break from the constant food collection and brood rearing duties that accompany a healthy colony. Winter also traditionally will provide fewer opportunities for the scavaging of food required to keep up brood production.
Yes – Your ants require hibernation and may even hibernate if you don’t encourage it.
During hibernation ants still, require a moist nest and water but will likely stop consuming any food or sugars offered. Many hobbyists use the 3-4 month hibernation period as a great way to take a break from the duties required for keeping colonies and enjoy the short break.
How Do I Hibernate My Ants?
When you local temperatures outside begin to drop below freezing for a few days in a row you should start the process of setting your colonies up for hibernation. Many times the observant ant-keeper will notice a change in their colonies behavior, less feeding and less activity being the most common. When this happens around November to December in Ohio, the only thing you need to do is to move the entire colony, including the outworld into a cool dark place in your home.
Popular locations include cool basements, warmer attics, garages that do not freeze, and even fridges set on their warmest setting. If possible, removing the outworld may make storing and relocating you colony easier, but it is not a requirement. During hibernation, there are only two things you need to monitor…
- Ensure your ant colony is not exposed to any prolong temps below freezing. 40F-50F is a great range to shoot for.
- Maintain proper hydration for your colony.
Because your nest is cooler, the humidity on your colony should not require as frequent monitoring but you do want to ensure it is not drying out. Colonies still found in test-tubes should be maintained in the same fashion as they have been maintained, but you should still keep them slightly cooler.
I also prefer to keep my hibernated ants covered and in the dark, I place a towel over the colony if it’s in my basement or attic to keep it dark and the temperature more stable in case of drafts or fast temperature swings.
Do I Feed Ants During Hibernation?
In most cases, ants will eat very little if anything during their hibernation period. You are welcome to offer food items, but ensure they do not mold if the food is not taken. It’s important to note as mentioned that you must continue to provide humidity AND drinking water during the hibernation period.
When Is Hibernation Over?
This is a pretty easy task, once your local environment begins to warm up you should be able to remove your colonies from hibernation. in Ohio, this is around Late February to early March. If the temperature is not an indication, be on the lookout for insects emerging outside and it will be safe to remove your colony from hibernation.
You may also attempt to artificially remove your colony from hibernation by increasing the temperature and re-introducing food to your colony. It does appear that most ant colonies have some internal biological clock that keeps them in hibernation and it might not be possible to remove them from hibernation until they are ready. If you intend to remove a colony from hibernation I would suggest giving your colony at least two months of solid hibernation time before beginning the transition out of hibernation.
What Happens If I Don’t Hibernate My Ant Colony?
While this is a possibility most myrmecologists agree that it will likely reduce the lifespan of the colony dramatically as it doesn’t give the queens and the colony as a whole a break from the massive amount of energy required to keep the colony growing and reproducing constantly.
Many hobbyists argue their ants a native to an area that doesn’t experience cold winters and colonies remain active throughout the year. There are arguments and some examples of colonies that have skipped hibernation. Generally speaking, even colonies that skip hibernation will still show signs of decreased activity during their normal hibernation time.
Difference Between Diapause and Hibernation
March 30, 2018 Posted by Samanthi
Key Difference – Diapause vs Hibernation
Hibernation is an adaptation that mammals possess in winter that makes them inactive and metabolically depressed. Diapause is another adaption that creates a temporary pause in the processes of growth and development of animals. Diapause takes place in adverse conditions during both winter and summer while hibernation takes place only during winter. This is the key difference between hibernation and diapause.
In the context of zoology, different animals possess different mechanisms to adapt to adverse environmental conditions. Unlike humans, most of the animals of the animal kingdom interact with the natural environment for their habitats in a close relationship. Seasonal changes and changes in weather patterns cause adverse effects on animals. So these animals naturally adapt to withstand these environmental changes. These adaptations include states of hibernation and diapause.
What is Diapause?
Diapause is defined as a state in which animals undergo to protect themselves from adverse environmental conditions. During this stage, animals undergo a temporary pause in the processes of growth and development. Diapause takes place in animal groups such as insects, mites, and crustaceans. It also includes embryos of oviparous species of fish in the order Cyprinodontiformes. The main intention of diapause is to protect from adverse environmental conditions such as extreme temperature conditions like winter, droughts and low food availability.
It takes place during both summer and winter. The occurrence of diapause could take place at any stage of life. But it was found out that, the most prominent stage of diapause takes place during the immobile stage of pupae. The level of diapause changes with species. Diapause could also occur at active stages of life that undergo extensive migration (example: adult monarch butterfly). Diapause is initiated with a decrement of bodily concentrations of growth and molting hormones.
Figure 01: Diapause
These fluctuations coincide with physical changes such as a change in temperature, day length and the availability of food. Unlike hibernation, diapause is a temporary effect for a short period of time. Diapause could be determined genetically. But a slight deviation occurs to this theory if the animal is raised under environmental conditions that are constant and favourable.
What is Hibernation?
Hibernation is defined as a state where the metabolic activity of animals reduce to a greater extent and lowers the body temperature that creates metabolically depressed conditions in them as an adaptation to withstand adverse environmental conditions during winter. This term, hibernation could be applied commonly to all types of dormant conditions develop by vertebrate animals. Therefore, hibernators include different types of fish, amphibians, reptiles and mammals like bears. These mammals use dens as hibernating habitats during winter.
Reptiles and mammals do not lower their body temperatures greatly, and they are not considered as true hibernators. A true hibernator spends most of the time period of winter in a state, which is close to death. Unless close observations are made, the animal may appear dead. Their body temperature is close to 0 0 C. The rate of respiration becomes low where it becomes almost very few breaths per minute. The heart rate becomes barely perceptible with slow and gradual beats. The animal slowly awakes only when it is exposed a considerable amount of heat. Once it receives the needed warmth, it requires additional 1-2 hours to reach the alert state.
Figure 02: Hibernation
True hibernators are present in all types of animal groups. In mammals, they are only found in the groups such as Chiroptera, Insectivora and Rodentia. Chiroptera including bats, Insectivora including hedgehogs, and Rodentia including marmots and ground squirrels. The food sources for hibernating animals include reserved body fat and stored food. The den protects the animal from physical harms.
What are the Similarities Between Diapause and Hibernation?
- Both Diapause and Hibernation occur in different species mammals and insects.
- Both Diapause and Hibernation result in adapting the animal to withstand extreme environmental conditions.
- Both Diapause and Hibernation prevent the death of animals due to adverse effects on the environment.
- Both Diapause and Hibernation takes place during winter.
What is the Difference Between Diapause and Hibernation?
Diapause vs Hibernation
Summary – Diapause vs Hibernation
Animal kingdom possesses different adaptations to withstand extreme environmental conditions. Diapause and hibernation are such states that protect the animals from the adverse effects of the environment. Dispose is defined as a state in which animals undergo to protect themselves from adverse environmental conditions where they undergo a temporary pause in the processes of growth and development. It is a temporary effect. It takes place during both winter and summer. Hibernation is defined as a state in which that reduces the metabolic activity of animals to a greater extent and lowers the body temperature that creates metabolically depressed conditions as an adaptation to withstand adverse environmental conditions during winter. True hibernators only lower their body temperature up to 0 0 C. This is the difference between diapauses and hibernation.
1.Britannica, The Editors of Encyclopaedia. “Hibernation.” Encyclopædia Britannica, Encyclopædia Britannica, Inc., 5 Jan. 2018. Available here
2.Britannica, The Editors of Encyclopaedia. “Diapause.” Encyclopædia Britannica, Encyclopædia Britannica, Inc., 31 May 2017. Available here
1.’DaphniaMagna LifeCycle DVizoso’By Dita Vizoso – Own work, (CC BY-SA 3.0) via Commons Wikimedia
2.’16202836808’by Global Panorama (CC BY-SA 2.0) via Flickr
Do Ants Hibernate While It’s Cold?
Video of the Day
According to AntWeb.org, more than 15,000 ant species are known. A University of Michigan website says the number’s between 8,800 and 20,000. Other sources put the number higher. In warm climates, these hard workers may stay busy year-round. But in colder climates, a winter break gives them an opportunity to slow down and regroup.
No Lazy Ants
Though you may not like seeing a trail of ants lining up on your kitchen counter, you have to appreciate ants’ industriousness. If the weather’s cooperating, these fellows are always busy, foraging for food, building or repairing the nest or caring for the colony’s young. However, when temperatures drop, the ants’ activity drops, too. The ants will gather as a colony to hibernate for the winter.
Hibernation, Not Starvation
As the air temperature drops, so do ants’ body temperatures — so much that they become sluggish. When the temperature drops to around 50 degrees Fahrenheit, ants may take sanctuary in nests under the soil or beneath tree bark. You wouldn’t find these spots particularly warm, but they’re warm enough for ants, particularly when they’re with their colony. They also prepare for their hibernation by eating more than usual during the autumn, fattening themselves up and storing food in their crops so they don’t have to worry about eating during the winter. Some ant colonies keep food on hand to help sustain them through the winter months.
Warmth in Numbers
The ant in an underground nest stays quite warm. The underground temperature can be much warmer than the outside cold air, and ants often capitalize on this by going deeper underground in the winter. They’re also smart enough to group together to share body heat. There’s not a lot of activity in the colony during the winter, as the members conserve energy for the coming months. By doing what comes naturally to them, ants are able to survive underground even when the outside temperature dips below zero.
An ant colony springs to life in early spring when the weather warms up. The ants will emerge from their nest, on the lookout for food. If they find something valuable, they’ll either return to the colony with it or, if it’s too large, get assistance for carrying the prize home. By late spring, the colony is fully active, repairing and maintaining the nest, foraging for food, and getting ready to mate in early summer. As summer progresses, ants assume their different roles in the colony; some ants gather food, other ants maintain the nest, and others feed and clean larvae. As the weather begins to cool, work turns to securing the nest for the coming winter.
Hello ant keepers of reddit, I have a problem. Recently someone on this reddit advised me that my l. Niger ants may be in diapause, not hibernation. I live in the uk and keep they at around 12c during the day and 5c at night. They are kept in a tubs and tubes setup buried in sand, which means their temperatures dont fluctuate quickly
The ants have completely blocked their test tube entrance with substrate.
They had 4 nurses at the start of hibernation and now have
12 workers, and larva and brood. This means their colony have been developing over winter.
They are all alive, definitely
They haven’t left the test tube at all since they began hibernation.
Their water is running low, and has a mold spot in their water chamber. They have had access to a fresher test tube but haven’t seemed interested. I can think of three options- they to lower the temperature further incase they truly are in diapause , which could kill them if I’m not careful. Pull them away from where they are, let them heat up slowly and try differently next year. This could also kill them unless I’m careful. Leave them as they are and hope they are somehow in hibernation. If they are in diapause they could starve to death, both workers and larva. If anyone has a different idea, their experience or thoughts please share them. I have researched thoroughly but I have little experience. This is the third time I’ve wrote this out as the browser keeps refreshing, sorry if there are any grammatical errors.