Overwintering is the process by which some organisms pass through or wait out the winter season, or pass through that period of the year when "winter" conditions (cold or sub-zero temperatures, ice, snow, limited food supplies) make normal activity or even survival difficult or near impossible. In some cases "winter" is characterized not necessarily by cold but by dry conditions; passing through such periods could likewise be called overwintering.
Hibernation and migration are the two major ways in which overwintering is accomplished. Animals may also go into a state of reduced physiological activity known as torpor. [1]
Overwintering occurs in several classes of lifeform.
In entomology, overwintering is how an insect passes the winter season. Many insects overwinter as adults, pupae, or eggs. This can be done inside buildings, under tree bark, or beneath fallen leaves or other plant matter on the ground, among other places. All such overwintering sites shield the insect from adverse conditions associated with winter. Activity almost completely ceases until conditions become more favourable. One example is the mourning cloak butterfly, which experiences advantages to overwintering in its desired locations by being one of the first butterflies to emerge after a cold winter. [2] Another example are the eggs of the forest tent caterpillar moth which overwinter tightly packed on tree branches. [3] Other insects, such as the monarch butterfly, migrate and overwinter in warmer areas. Additionally, the ghost moth overwinters as a larva. The common brimstone, found across a broad geographic range, overwinters for 7 months to wait for the development of their larval host plants. [4] Another unique butterfly, the large white, will only overwinter in southern Eurasia; they are not seen overwintering elsewhere. [5] Some species of parasitic conopid flies, such as P. tibialis, are known to overwinter inside of the corpse of their bee/wasp hosts before emerging in the spring. [6] The queens of the yellow-faced bumblebee (Bombus vosnesenskii) will over-winter, and then emerge early in the flight season to obtain the best available subterranean nests. [7] Lastly, many species of Lasioglossum, including L. hemichalceum (which is a common sweat bee), will overwinter in underground nests before emerging in the spring to start new colonies. [8]
Many birds migrate and then overwinter in regions where temperatures are warmer or food is more readily available, in Europe for example common crane and white storks. Some birds, however, such as black-capped chickadees, Golden-crowned kinglets, woodpeckers, and corvids, instead remain in colder areas throughout the winter, often remaining in groups for warmth. [9]
Plants are sometimes said to overwinter. At such times, growth of vegetative tissues and reproductive structures becomes minimal or ceases completely. For plants, overwintering often involves restricted water supplies and reduced light exposure. In the spring following overwintering many plants will enter their flowering stage. Farmers and gardeners use a process of "overwintering" [10] to achieve early spring harvests of some crops by planting annual or biennial species in fall, often under the protection of high or low tunnels. [11] In plant pathology, overwintering is where a plant pathogen survives the winter, during which its normal crop host species is not growing, by transferring to an alternative host, living freely in the soil or surviving on plant refuse such as discarded potatoes.
People are also described from time to time as overwintering. This was especially true in the past during the exploration of the planet when people had to pass the winter in places not ideally suited for winter survival, and even today in the polar regions. Today people may be said to overwinter when they temporarily move to warmer areas during the months of prevailing cold weather in northern latitudes, such as people from various parts of North America staying in Florida, Arizona, or New Mexico (among other places) for parts of November to March.
Hibernation is a state of minimal activity and metabolic depression undergone by some animal species. Hibernation is a seasonal heterothermy characterized by low body-temperature, slow breathing and heart-rate, and low metabolic rate. It is most commonly used to pass through winter months – called overwintering.
A bumblebee is any of over 250 species in the genus Bombus, part of Apidae, one of the bee families. This genus is the only extant group in the tribe Bombini, though a few extinct related genera are known from fossils. They are found primarily in higher altitudes or latitudes in the Northern Hemisphere, although they are also found in South America, where a few lowland tropical species have been identified. European bumblebees have also been introduced to New Zealand and Tasmania. Female bumblebees can sting repeatedly, but generally ignore humans and other animals.
The small tortoiseshell is a colourful Eurasian butterfly in the family Nymphalidae. Adults feed on nectar and may hibernate over winter; in warmer climates they may have two broods in a season. While the dorsal surface of the wings is vividly marked, the ventral surface is drab, providing camouflage. Eggs are laid on the common nettle, on which the larvae feed.
An ectotherm, more commonly referred to as a "cold-bloodedanimal", is an animal in which internal physiological sources of heat, such as blood, are of relatively small or of quite negligible importance in controlling body temperature. Such organisms rely on environmental heat sources, which permit them to operate at very economical metabolic rates.
Pieris brassicae, the large white, also called cabbage butterfly, cabbage white, cabbage moth (erroneously), or in India the large cabbage white, is a butterfly in the family Pieridae. It is a close relative of the small white, Pieris rapae.
Nymphalis antiopa, known as the mourning cloak in North America and the Camberwell beauty in Britain, is a large butterfly native to Eurasia and North America. The immature form of this species is sometimes known as the spiny elm caterpillar. Other older names for this species include grand surprise and white petticoat. A powerful flier, this species is sometimes found in areas far from its usual range during migration.
Gonepteryx rhamni, commonly named the common brimstone, is a butterfly of the family Pieridae. It lives throughout the Palearctic zone and is commonly found across Europe, Asia, and North Africa. Across much of its range, it is the only species of its genus, and is therefore simply known locally as the brimstone. Its wing span size is 60–74 mm (2.4–2.9 in). It should not be confused with the brimstone moth Opisthograptis luteolata.
Bombus fraternus is an endangered species of bumblebee known commonly as the Southern Plains bumblebee. It is native to the United States east of the Rocky Mountains. It is most often encountered in the southern Great Plains and along the Gulf Coastal Plain. This species has been found as far north as New Jersey and North Dakota, and as far south as Florida along the Gulf Coastal Plain into the state of Chihuahua in Mexico. This species was uncommon historically, but having faced declines in population; its estimated abundance is less than 15% of historical numbers.
Insect winter ecology describes the overwinter survival strategies of insects, which are in many respects more similar to those of plants than to many other animals, such as mammals and birds. Unlike those animals, which can generate their own heat internally (endothermic), insects must rely on external sources to provide their heat (ectothermic). Thus, insects persisting in winter weather must tolerate freezing or rely on other mechanisms to avoid freezing. Loss of enzymatic function and eventual freezing due to low temperatures daily threatens the livelihood of these organisms during winter. Not surprisingly, insects have evolved a number of strategies to deal with the rigors of winter temperatures in places where they would otherwise not survive.
A hibernaculum is a place in which an animal seeks refuge, such as a bear using a cave to overwinter. The word can be used to describe a variety of shelters used by many kinds of animals, including insects, toads, lizards, snakes, bats, rodents, and primates of various species.
Bombus polaris is a common Arctic bumblebee species. B. polaris is one of two bumblebees that live above the Arctic Circle. The other is its social parasite Bombus hyperboreus. B. polaris is a social bee that can survive at near freezing temperatures. It has developed multiple adaptations to live in such cold temperatures. B. polaris has a thicker coat of hair than most bees, utilizes thermoregulation, and makes insulated nests.
Bombus suckleyi is a species of bumblebee known commonly as Suckley's cuckoo bumblebee, named after biologist George Suckley. Suckley's bumble bee is a generalist pollinator and represents a rare group of obligate, parasitic bumble bees. Suckley's bumble bee is a social-parasite because it invades the nests of the host bumble bees, including the western bumble bee, and relies on host species workers to provision its larvae. It is native to northwestern North America, including Alaska and parts of western and central Canada and the western United States.
Bombus pensylvanicus, the American bumblebee, is a threatened species of bumblebee native to North America. It occurs in eastern Canada, throughout much of the Eastern United States, and much of Mexico.
The two-spotted bumble bee is a species of social bumble bee found in the eastern half of the United States and the adjacent south-eastern part of Canada. In older literature this bee is often referred to as Bremus bimaculatus, Bremus being a synonym for Bombus. The bee's common name comes from the two yellow spots on its abdomen. Unlike many of the other species of bee in the genus Bombus,B. bimaculatus is not on the decline, but instead is very stable. They are abundant pollinators that forage at a variety of plants.
Bombus vosnesenskii, the yellow-faced bumblebee, is a species of bumblebee native to the west coast of North America, where it is distributed from British Columbia to Baja California. It is the most abundant species of bee in this range, and can be found in both urban and agricultural areas. Additionally, B. vosnesenskii is utilized as an important pollinator in commercial agriculture, especially for greenhouse tomatoes. Though the species is not currently experiencing population decline, urbanization has affected its nesting densities, and early emergence of the B. vosnesenskii has been implicated in the increasing lack of bee diversity on the West coast.
Bombus affinis, commonly known as the rusty patched bumble bee, is a species of bumblebee endemic to North America. Its historical range in North America has been throughout the east and upper Midwest of the United States, north to Ontario, Canada, where it is considered a "species at risk", east to Quebec, south to Georgia, and west to the Dakotas. Its numbers have declined in 87% of its historical habitat range. On January 10, 2017, the United States Fish and Wildlife Service placed B. affinis on the list of endangered species, making the rusty patched bumblebee the first bee to be added to the list in the continental United States.
Halictus ligatus is a species of sweat bee from the family Halictidae, among the species that mine or burrow into the ground to create their nests. H. ligatus, like Lasioglossum zephyrus, is a primitively eusocial bee species, in which aggression is one of the most influential behaviors for establishing hierarchy within the colony, and H. ligatus exhibits both reproductive division of labor and overlapping generations.
Potato leafhopper belongs to family Cicadellidae and genus Empoasca within order Hemiptera. In North America they are a serious agricultural pest. Every year millions of dollars are lost from reduced crop yields and on pest management. Crops that are impacted the most are potatoes, clover, beans, apples and alfalfa.
Lasioglossum sordidum, also referred to as the small native bee, is one of the smallest native bees found in New Zealand.
Bombus lantschouensis is one of many bumblebee species native to China. Like all bumblebee species, they are characterized by their round bodies that are larger than honeybees. They have diverse color patterns. but are known for their eye-catching black and yellow coloring. They are also known for their furry-like appearance due to their body being covered in soft hair which are long branched setae. This hair is referred to as pile.