Planet Zoo 2 animal breeding guide

What breeding depends on

Frontier's official "Animals" guide gives a simple rule: healthy adult animals mate during their mating season, as long as they are not already nurturing offspring.

Some species are simply more fertile than others, and some become sterile after a certain age. You will find both in the Zoopedia.

Steps according to Frontier:

1. Check the breeding requirements and mating season in the Zoopedia or the Info Panel (for example Spring or Winter; some species breed all year round).
2. You will see whether a nest is needed on the Overview screen of the Info Panel, under Social needs as "Nesting Sites".
3. On the Genetics screen, compare candidates with Compare Mates. The screen also shows obstacles such as Low Welfare or Illness: fix them before the season.
4. A healthy pair in comfortable surroundings will breed during the season if it has no juvenile to look after.

Seasons and seasonal fertility

This is new compared to the first game. Some animals now have seasonal fertility: they can only breed at specific times of the year. If they are not feeling well during that time, you will have to wait a year for the next attempt.

Species that breed all year round give you a steady stream of young instead. Frontier suggests considering contraception for them.

The Zoopedia does not list the mating season in its stats. According to the Wikily fan wiki, Summer is the season for the Aardvark, Shoebill and Common Ostrich, and Spring for the Golden Eagle. We have not verified this in game.

Nests for birds and egg-laying animals

A mixed-sex group of egg-laying animals needs at least one nest per pair in the Habitat. Only pairs with access to a nest can mate. This also applies to flying birds in aviaries.

Each species has its own Nest Type. You will find it under Browser → Habitats → Bedding, Shelters, and Nests → Nests (with the species filter), or by clicking the "Nesting Sites" need in the Info Panel: the browser will show matching nests.

Some species incubate their eggs and raise chicks in the nest, others bury the eggs and leave, and the young fend for themselves after hatching.

Genetics: Vitality, Longevity, Fertility and Immunity

Every animal has its own DNA inherited from both parents. The official guide lists four genes in two groups.

Each gene is 6 pairs of letters A, B, C and D. The offspring gets one letter from each parent, and a letter has a low chance to mutate. Inbreeding creates doubled pairs and lowers Fertility and Immunity over successive generations. Offspring can turn out better or worse than their parents.

There is no Size gene in Planet Zoo 2: in the first game the additive genes were Size and Longevity, while the official guide for the sequel lists Vitality in that pair. Young usually look similar to their parents; colourmorphs do exist, for example the Zoopedia lists Leucistic for the Common Ostrich.

How to raise the Genetic Rating according to Frontier:

1. Compare the candidates' genes on the Genetics screen before breeding.
2. Pair animals with different genetic traits.
3. Give the pair good welfare and research the species (Fertility boost).
4. Adopt animals with a good Genetic Rating from the Trade Centre and breed them with your own.

Genetics matter later too. Release group requirements can include a certain level of longevity, fertility or genetic diversity, and animals with high-rated genes in their prime earn more Conservation Credits (CC). More: accreditation and Conservation Credits.

Compare Mates and Animal Genealogy

Compare Mates on the Genetics screen shows the "likely genetic outcomes" for a pair. The Animal Genealogy screen brings together an animal's parents, siblings, partners and offspring along with their genes, so avoiding inbreeding is easy. Since launch, Compare Mates is sometimes broken (see the issues below).

Contraception and separation

You control numbers by separating animals into different Habitats or by applying contraception. Animals on contraception do not breed.

1. Select the animal → Info Panel → Overview screen → Apply Contraceptives toggle (On/Off).
2. Or open Management > Animals and switch Contraceptives for any animal in your zoo.

Contraception also stops shoals and colonies from splitting. These animals do not breed in pairs and have no genetics: the group refills itself. More in the aquariums and fish guide.

Ageing and time: a year lasts 60 minutes

Frontier confirmed that a year in the original Planet Zoo lasted 18 minutes of real time, while in Planet Zoo 2 it lasts 60 minutes. That means about a quarter of an hour per season. Patch 1.0.4 from October 14, 2026 improved "Animal breeding frequency and success rate", without giving numbers.

We have not confirmed a slow ageing slider in Planet Zoo 2 like the one the first game got in update 1.1 (Slow Animal Aging). Frontier describes the longer year as a feature of the game, not an option.

According to the Wikily fan wiki, Sandbox mode has an Enable Animal Ageing and Birth toggle (Lifecycle category): on in the Default and Challenge presets, off in Creative. When it is off, animals do not age and pregnancies do not advance. Officially, Frontier only says that Sandbox settings include Economy and Animal Welfare among others; we have not checked the toggle in game.

About growing young:

• Juveniles do not increase space requirements, but a maturing male can cause discomfort to adult males.
• In some species, young become Outsiders when they mature: the group rejects them and you have to move them.
• Siblings in the same Habitat are Bonded by default and do not fight each other.

Reproduction stats from the Zoopedia

Data from the official Zoopedia, checked October 18, 2026. Frontier notes that the stats are not final.

"Death" is the value the Zoopedia gives for sterility: the animal does not lose fertility with age. The Zoopedia also shows numbers next to the Juvenile, Adult and Elderly stages, but Frontier does not explain what they mean, so we do not list them.

The Common Ostrich in the Zoopedia: a group of 1-8 animals, at most 1 male and 7 females. Other species: all animals list.

What to do with offspring

Only healthy, stable adults can be traded. You cannot sell an animal while it is Juvenile, Gestating, Elderly, Sick or Injured. So you have to raise the young and plan a new Habitat for them, a move to another zoo or a release to the wild.

Animal Storage is shared by all your zoos, and its capacity grows with your Accreditation Tier. Send an animal there with the "Send animal to Storage in Trade Centre" button in the Info Panel or via Move → Animal Trading Centre (the Trade Centre must be connected to paths).

Release groups (from single animals, through breeding pairs, to larger herds) raise their young in the wild in Wildlife Reserves. Players warn that a group does not come back to your zoo after "Finalize Release Group". Details: Wildlife Reserves. Quick sell and release for exhibit animals do not work correctly yet: Frontier listed this among its priorities in the 1.0.5 notes.

Known breeding issues

Patch 1.0.4 also fixed juvenile birds in Wildlife Reserves staying stuck in their nest when their group migrated.