Zebrafish (Zebra Danio)
Scientific name: Danio rerio
Tireless schooling swimmer that needs horizontal space to move.
Quick facts
- Approximate size3–5 cm
- Average weight1–2 g
- Life expectancy3–5 years (captivity)
- ActivityDiurnal
Basic information
- Habitat: streams, canals, and rice paddies with slight current in South Asia.
- Diet: small invertebrates, plankton, and finely ground prepared food.
- Sexual dimorphism: females more rounded and males more slender and somewhat more intense in color.
- Predators: larger fish, birds, and other vertebrates that hunt in shallow waters.
Life in the wild
How this species lives in its natural environment, with the waters, shelters and resources it needs.
Species overview
The zebrafish is both a popular aquarium fish and a key piece in biomedical research.
Natural habitat
It occupies clear and shallow waters with some current and scattered vegetation.
Behavior
It swims constantly in the middle and upper zone of the aquarium, following the group.
Special features
Its transparent embryos facilitate the study of organ and tissue development.
Conservation and threats
In the wild it remains relatively common; the main threat is the alteration of rivers and canals.
Curiosities
Striking details about this species that help better understand its biology and role in aquatic ecosystems.
- It is one of the most used model organisms in developmental biology and genetics.
- It likes to live in schools of at least 6–8 individuals.
- It tolerates a wide range of conditions, making it hardy.
- Its horizontal stripes help the group stay cohesive.
Welfare profile
Summary of the most critical points if this species is kept in aquariums, ponds or specialized facilities.
Space and facilitiesMedium
It needs aquariums with horizontal space to swim in groups, not just vertical.
Water quality and parametersLow
It is very hardy and tolerates a wide range of water parameters.
Handling and stressLow
It is an active fish that adapts well to human presence when in a group.
Zebrafish (Zebra Danio) in captivity
General information aimed at professional facilities, public aquariums and educational projects. It does not intend to promote capture or impulsive keeping of aquatic fauna.
⚠️ Before keeping fish like this species, it is essential to review local regulations, ensure adequate facilities and minimize impact on wild populations.
Suitable facilities
Ideal for community aquariums with calm and similarly sized companions.
Feeding in responsible centers
The diet includes fine food, small live prey, and frozen food.
Handling and welfare
It is essential to keep them in groups of at least 6–8 individuals so they show their natural behavior.
Ethical message
In education it can be used to talk about animal models in research and schooling behavior.
Many aquatic species suffer from massive captures, uncontrolled trade and irresponsible releases. The priority should always be to protect rivers, lakes and seas, reduce pollution and consume seafood responsibly.