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Gestation periods of animals
The Gestation period in a viviparous animal is the length of its gestation. In humans this is 266 days (38 weeks), but varies for other animals. Gestation period is measured from conception to birth. A viviparous animal is an animal employing vivipary: the embryo develops inside the body of the mother, from which it gains nourishment, as opposed to in an egg (ovipary). The mother then gives live birth. Viviparous offspring live independently and require an external food supply from birth. Vivipary is best developed in placental mammals, but also occurs in many reptiles, some amphibians, crustaceans (eg. Daphnia), scorpions, insects (aphids, the tsetse fly, some cockroaches) and a few fish.
In most birds and reptiles, an egg (Latin: ovum) is the zygote, resulting from fertilization of the ovum. It nourishes and protects the embryo. Oviparous animals are animals that lay eggs, with little or no other development within the mother. This is the reproductive method of many fish, amphibians and reptiles, all birds, the monotremes, and most insects and arachnids.
Ovoviviparous animals develop within eggs that remain within the mother's body up until they hatch or are about to hatch. This strategy of birth is known as ovoviviparity. It is similar to vivipary in that the embryo develops within the mother's body. Unlike the embryos of viviparous species, ovoviviparous embryos are nourished by the egg yolk rather than by the mother's body. However, the mother's body also provides for gas exchange.
Ovoviviparity is employed by many fish (including sharks), reptiles, and invertebrates. The young of ovoviviparous amphibians are sometimes born as larvae, and undergo metamorphosis outside the body of the mother.
Photo: BBC
Below you'll find the gestation period of most animals.
Clicking on the animals name will link you to Wikipedia for more information.
Live-bearing
animals
American Black Bear: 7 months
Anteater: 190 days
Arctic Fox: 50 days
Bat: 46 - 70 days
Beaver: 100 - 110 days
Blue whale: 11 - 12 months
Bonobo: 8 months
Brown bear: 255 days
Cat: 63 (58 - 64) days
Cheetah: 90 - 95 days
Chinchilla: 111 (105 - 118) days
Common Chimpanzee: 202 - 261 days
Cow: 9 months (275 - 300 days) >>>
Dog: 63 days
Dolphin: 350 days
Donkey: 275 days (10,5 - 14,4 months)
Elephant (African): 18 - 22 months
Elephant (Asian): 20 - 22 months
Euregian Badger: Female badgers can display delayed implantation: after mating at any time of the year, they keep the fertilised eggs in suspended development until an appropriate time, at which stage the eggs are implanted and begin developing. Badgers have a gestation period of 7 - 8 weeks and give birth to 1 - 5 offspring.
European polecat: 6 weaks
Ferret: 42 (41 - 44 days)
Fallow Deer: 234 (225 - 237) days
Fox: 52 - 53 days
Gerbil: 24 - 26 days
Giant Panda: 5 months
Gibbon: 30 weaks
Giraffe: 475 days
Goat: 150 (146 - 157) days
Gorilla: 9 months
Guinea Pig: 2 - 2,5 months
Guppy: 4 - 5 weaks
Hamster: 15 - 17 days
Harbour porpoise: 11 months
Hedgehog: 31 - 35 days
Hippopotamus: 240 days
Horse: 335 - 342 days (320-370)
Howler monkey: 6 months
Human: 280 days
Hyena: 110 days
Indian Rhino: 16 months
Jaguar: 110 days
Kangaroo: As with all marsupials, the young are born at a very early stage of development after a gestation of 31-36 days. At this stage, only the forelimbs are somewhat developed, to allow the newborn to climb to the pouch and attach to a teat. In comparison, a human embryo at a similar stage of development would be about 7 weeks old, and premature babies born at less than 23 weeks are usually not mature enough to survive. The joey will usually stay in the pouch for about 9 months or (for the Western Grey) 180 to 320 days, before starting to leave the pouch for small periods of time. It is usually fed by its mother until the age of 18 months.
Lemming: 20 - 22 days
Llama: 331 - 367 days
Lion: 105 - 110 days
Moose: 240 - 270 days
Mole: 4 - 6 weeks
Mouse: 19 - 24 days
Muskrat: 25 - 30 days
Mink: 50 (39 - 59) days
Opossum: 13 days
Orangutan: 275 days
Otter: 61 - 63 days
Pale-throated Three-toed Sloth: 170 days
Pig: 115 days
Polar Bear: 240 days
Puma: 91 days
Rabbit: 30 - 31 days
Raccoon: 60 - 73 days
Rat: 18 - 23 days
Red deer: 231 (226 - 238) days
Sheep: 147 (137 - 152) days
Spider Monkey: 7 months
Skunk: 2,5 months
Squirrel: 5 - 6 weaks
Tiger: 104 - 112 days
True Seals: 8 - 8,5 months, though there is an extended gestation: the development of the embryo starts around 1,5 - 3 months after mating.
Weasel: 34 - 37 days
Whale: 1 year
Wolf: 63 days
Zebra: 12 - 13 months
American Black Bear: 7 months
Anteater: 190 days
Arctic Fox: 50 days
Bat: 46 - 70 days
Beaver: 100 - 110 days
Blue whale: 11 - 12 months
Bonobo: 8 months
Brown bear: 255 days
Cat: 63 (58 - 64) days
Cheetah: 90 - 95 days
Chinchilla: 111 (105 - 118) days
Common Chimpanzee: 202 - 261 days
Cow: 9 months (275 - 300 days) >>>
Dog: 63 days
Dolphin: 350 days
Donkey: 275 days (10,5 - 14,4 months)
Elephant (African): 18 - 22 months
Elephant (Asian): 20 - 22 months
Euregian Badger: Female badgers can display delayed implantation: after mating at any time of the year, they keep the fertilised eggs in suspended development until an appropriate time, at which stage the eggs are implanted and begin developing. Badgers have a gestation period of 7 - 8 weeks and give birth to 1 - 5 offspring.
European polecat: 6 weaks
Ferret: 42 (41 - 44 days)
Fallow Deer: 234 (225 - 237) days
Fox: 52 - 53 days
Gerbil: 24 - 26 days
Giant Panda: 5 months
Gibbon: 30 weaks
Giraffe: 475 days
Goat: 150 (146 - 157) days
Gorilla: 9 months
Guinea Pig: 2 - 2,5 months
Guppy: 4 - 5 weaks
Hamster: 15 - 17 days
Harbour porpoise: 11 months
Hedgehog: 31 - 35 days
Hippopotamus: 240 days
Horse: 335 - 342 days (320-370)
Howler monkey: 6 months
Human: 280 days
Hyena: 110 days
Indian Rhino: 16 months
Jaguar: 110 days
Kangaroo: As with all marsupials, the young are born at a very early stage of development after a gestation of 31-36 days. At this stage, only the forelimbs are somewhat developed, to allow the newborn to climb to the pouch and attach to a teat. In comparison, a human embryo at a similar stage of development would be about 7 weeks old, and premature babies born at less than 23 weeks are usually not mature enough to survive. The joey will usually stay in the pouch for about 9 months or (for the Western Grey) 180 to 320 days, before starting to leave the pouch for small periods of time. It is usually fed by its mother until the age of 18 months.
Lemming: 20 - 22 days
Llama: 331 - 367 days
Lion: 105 - 110 days
Moose: 240 - 270 days
Mole: 4 - 6 weeks
Mouse: 19 - 24 days
Muskrat: 25 - 30 days
Mink: 50 (39 - 59) days
Opossum: 13 days
Orangutan: 275 days
Otter: 61 - 63 days
Pale-throated Three-toed Sloth: 170 days
Pig: 115 days
Polar Bear: 240 days
Puma: 91 days
Rabbit: 30 - 31 days
Raccoon: 60 - 73 days
Rat: 18 - 23 days
Red deer: 231 (226 - 238) days
Sheep: 147 (137 - 152) days
Spider Monkey: 7 months
Skunk: 2,5 months
Squirrel: 5 - 6 weaks
Tiger: 104 - 112 days
True Seals: 8 - 8,5 months, though there is an extended gestation: the development of the embryo starts around 1,5 - 3 months after mating.
Weasel: 34 - 37 days
Whale: 1 year
Wolf: 63 days
Zebra: 12 - 13 months
Egg-laying
animals
Bald Eagle: 45 days
Bearded Dragon: 70 days
Canary: 12 - 14 days
Chicken: 21 days
Common Kestrel: 27 days
Dove: 17 - 18 days
Duck: 23 - 24 days
Emperor Penguin: 67 days
Emu: 50 days
European Starling: 12 days
Goose: 30 days
House Sparrow: 12 - 15 days
Komodo Dragon: 8 - 9 months
Nile Crocodile: 96 days
Ostrich: 40 - 44 days
Parakeet: 16 - 31 days
Peafowl: 31 days
Pheasant: 24 days
Platypus: 10 days (the Platypus is actually a mammal, she does lay eggs but she feeds her offspring with milk from her mammary glands).
Robin: 12 - 15 days
Snake: 2 - 3 months
Swan: 30 days
Turtle: 100 days
Young turtle
Baby kangaroo in pouch
Baby orangutan with mother
Baby crocodile
Bald Eagle: 45 days
Bearded Dragon: 70 days
Canary: 12 - 14 days
Chicken: 21 days
Common Kestrel: 27 days
Dove: 17 - 18 days
Duck: 23 - 24 days
Emperor Penguin: 67 days
Emu: 50 days
European Starling: 12 days
Goose: 30 days
House Sparrow: 12 - 15 days
Komodo Dragon: 8 - 9 months
Nile Crocodile: 96 days
Ostrich: 40 - 44 days
Parakeet: 16 - 31 days
Peafowl: 31 days
Pheasant: 24 days
Platypus: 10 days (the Platypus is actually a mammal, she does lay eggs but she feeds her offspring with milk from her mammary glands).
Robin: 12 - 15 days
Snake: 2 - 3 months
Swan: 30 days
Turtle: 100 days
Young turtle
Baby kangaroo in pouch
Baby orangutan with mother
Baby crocodile
