The European bitterling is a small freshwater fish up to 9 centimeters long. It lives in rivers and lakes and lays its eggs inside bivalve mollusks.
The European loach differs from other fish by using mollusks to protect its offspring. It serves as an indicator of clean water because it cannot reproduce successfully without certain mollusks.
Immature form that undergoes metamorphosis before adulthood.
pecking
Worker
birth time
bottom
Dogs, dolphins, lynx hang out for 9-25 years and party on their birthday three times a year
m
Map
will celebrate their {n} birthday
g
t
When your next jubilee falls in {name} life years
Human
detritus, eat dead remains of plants, animals and all kinds of organic debris on the bottom
days
How old you would be if you lived as {name}
crustaceans
Theoretical maximum lifespan estimated from the Dynamic Energy Budget (DEB) mathematical model. This value reflects a biological potential derived from metabolic parameters, not from direct observation — real recorded lifespans are often significantly shorter.
small planktonic crustaceans — copepods, krill
adult
Maturity
organic debris
plant
invertebrates
About health
Searches for food on or among rocks and stony surfaces.
When your next birthday would fall if you lived as {name}
Repro interval
results
Colors
Sex
Upcoming jubilees
Gremllins
mo
Trophic type
all living animals without backbone
Filters
Palearctic realm
Upcoming birthdays
Truly long lives: 40-100 years. Bowhead whales, albatrosses, giant tortoises recall their birthday at most once a year
Lifespan
leaf
Height
Age (juvenile)
insect larvae and caterpillars
Age (from birth to death)
rock
Foraging occurs on the floor of aquatic or terrestrial habitats.
Age (embryo)
most of Europe and Asia, various forests, steppes and tundra
Wanderers
Food items are collected from exposed outer surfaces of substrates.
algae
Jubilee = every 10th birthday
Earliest developmental stage inside an egg or womb.
Business sausages
Lifespan average
leaves
What do they look like?
Maturity
emergence (insects)
end of lifespan
How do they live?
fertilization / egg laying
How do they behave?
birth / hatching
metamorphosis / end of larval stage
end of acceleration
Share
swampy freshwater biotopes — peat bogs, marshes, river mangroves
Find a pet...
Mature, fully developed individual capable of reproduction.
Freshwater
Pets
all rivers and lakes
Primary oral structure used to seize, manipulate, or ingest food.
Repeatedly strikes or probes substrate with beak to obtain food.
Lots of rain and cool summer
Feeding occurs primarily on land or in vegetation.
{name} jubilee
cm
Old-timers
Find an animal or breed...
mouth
turns
Rascals
Flooded grasslands
after fast growth and adult
Litter size
Map data sources: Ecosystem classification — IUCN Global Ecosystem Typology (Keith et al., 2022), indicative distribution maps Keith et al. (2020), https://doi.org/10.5281/zenodo.3546513; Large Marine Ecosystems — NOAA LME Program; Bathymetry — GEBCO Bathymetric Compilation Group (2026), GEBCO_2026 Grid, https://doi.org/10.5285/4f68d5c7-45eb-f999-e063-7086abc036fa; Climate data — Generated using Copernicus Climate Change Service information; Species occurrence data — GBIF.org, Derived dataset "all animals", https://zveriki.com/dataset/dataset.tsv; Terrestrial ecoregions — RESOLVE Ecoregions 2017 (Dinerstein et al., 2017), CC BY 4.0
How to care for them?
Living from 25 to 40 years. Orangutans, bald eagles, African elephants celebrate their birthday twice a year
°C
Not specified
Actively searching habitats to locate food items.
Where are they found?
Species lacks any fixed or lasting shelter structure.
all rivers and lakes
lots of rain, cool summer, snow in winter
Locomotion through water employed while searching for or capturing prey.
Legendary longevity: over 100 years. Galapagos tortoises, Greenland sharks, ocean quahogs celebrate with family once every 4 years
Offspring
Elders
Bro
freshwater marsh and wetlands
Taxons
freshwater pelagic
if born as {name}
omnivore
age
birth date
swimming
no permanent shelter
Palearctic realm
Ovipositor color
Close
water column
was
Career from 7 to 15 months. Dwarf hamsters, voles, field crickets celebrate their birthday twice a month
The basics
climbing
My weight?
Non-stop carnival: they only live a few days. Mayflies, rotifers, midges celebrate their birthday more than twice a day
surface
primary food sources
Potential Habitat
d
In husbandry
Feeds while suspended in open water between surface and bottom.
On the go from 1.3 to 3.5 years. Forest mice, anoles, rainbow fish party on their birthday once a month
Feeding occurs in water bodies such as rivers, lakes, or oceans.
Mass
Ovipositor count
young shoots and leaves of plants
cold winter, lots of coniferous trees: spruce, pine
Mosquitoes, fruit flies, small crustaceans hustle for up to 7 months and throw a birthday party every week
terrestrial
Gestation
Body size
aquatic
{name} birthday
Food is gathered directly from leaf surfaces.
No results found
Ovipositor size
On the map
all life stages
Female ♀
Body color
Map data sources: Ecosystem classification — IUCN Global Ecosystem Typology (Keith et al., 2022), indicative distribution maps Keith et al. (2020), https://doi.org/10.5281/zenodo.3546513; Large Marine Ecosystems — NOAA LME Program; Bathymetry — GEBCO Bathymetric Compilation Group (2026), GEBCO_2026 Grid, https://doi.org/10.5285/4f68d5c7-45eb-f999-e063-7086abc036fa; Climate data — Generated using Copernicus Climate Change Service information; Species occurrence data — GBIF.org, Derived dataset "all animals", https://zveriki.com/dataset/dataset.tsv; Terrestrial ecoregions — RESOLVE Ecoregions 2017 (Dinerstein et al., 2017), CC BY 4.0
Potential habitat modelled from GBIF occurrence data. Map © Zveriki.com, licensed under CC BY 4.0.
open water in the water column of a freshwater body, away from the bottom and shore
birth year
Maturity
sq mm
yr
How similar?
Male ♂
until the celebration
age as {name}
How do they breed?
On the go from 3.5 to 6 years. Hedgehogs, crows, lizards treat themselves to birthday snacks 6 times a year
What if eaten?
Neither
Moving up vertical surfaces like trunks or rocks to reach food.
What do they eat?
insect larvae
Where do they live?
early young
water often floods the land, lots of grass
Freshwater
Temperate mixed forest
Duration
Fins color
This is me
most of Europe and Asia, various forests, steppes and tundra
freshwater
Gamers
aquatic plants and algae
How are they built?
mm
Theoretical lifespan
ml
Stars
Link copied
My age?
wk
My size?
Taiga
Asexual
swap
freshwater environment — rivers, lakes, ponds, swamps
Rabbits, falcons, red-eared turtles hang out for 6-9 years and party on their birthday four times a year
Where do they take shelter?
Warm summer and lots of rain
celebrated their {n} birthday
When you would have been born if you lived as {name}
Daddies
Gills count
Lifespan maximum
foraging
whole life
Hermaphrodite ⚥
Grape
8 to 11 grams, 1.5 – 8 centimeters
embryo
summer warm, many oaks, birches, maples
Length
kg
lots of rain, warm and pleasant summer
Observations
◉{N} more on tap