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  3. Marsh Deer

One of the 12 deer on WAnimals

Marsh Deer (Blastocerus dichotomus)

Mammals · Artiodactyla · Cervidae

Marsh Deer

Blastocerus dichotomus

Vulnerable

At high risk of extinction in the wild over the medium term.

Spotted something wrong?

The marsh deer is the largest deer in South America and is wholly adapted to life in wetlands. Its hooves are long, widely splayed and joined by an elastic membrane that spreads its weight over the mud, and they serve as paddles when it swims. Its legs are black to above the knee, as though it were wearing stockings. It browses aquatic plants and rushes. The draining of wetlands for farming and grazing, together with hunting, has broken it up into isolated populations.

Weight

80 kg – 150 kg

Size

1.5 m – 2 m

Life expectancy

18 years

Diet

Herbivore

Feeds mainly on plants.

Activity

Crepuscular

Active mainly at dawn and dusk.

Social structure

Solitary

Lives and hunts alone, joining others only to breed.

Sighting difficulty

Moderate

FreshwaterGrassland
8countries5parks23same family

AI-generated images: illustrations, not photographs.

Fun facts

  • GeneralThe largest deer in South America; it has webbing between its hooves for walking on mud.
  • Its hooves are joined by an elastic membrane that spreads as it steps on soft mud and works like a snowshoe: it can walk over mats of floating vegetation where any other deer would sink.
  • It is an accomplished swimmer: it crosses wide river channels with only its head and antlers above the water.

Life cycle and biology

Skeleton type
Vertebrate - internal bony skeleton (mammal)
Habitat and environment
Wetlands, marshes, swamps and floodplains with aquatic vegetation in South America
Sexual maturity
2 years
Gestation / incubation
8.9 months
Litter / clutch size
1

Sources consulted: https://es.wikipedia.org/wiki/Blastocerus_dichotomus

Where to find it

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The pins mark the parks where its presence is documented.

Where to see it

Parks and dive sites where this species has been documented.

Related species

Other species in the catalogue with the most in common with Marsh Deer — same habitat, park, country, tags or family.

Same taxonomic family
Same taxonomic family
Shares a park
Shares a park
Same taxonomic family
Same taxonomic family

How to help

The marsh deer is classified as vulnerable. Organisations such as the IUCN, WWF and the Wildlife Conservation Society work specifically on its conservation and that of its habitat; looking into their programmes is a good starting point if you want to get involved.

It's documented in 5 protected areas — one reason why protecting these places matters for its conservation.

Keep exploring

Based on what we already know about marsh deer.

Comments

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See full glossary
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See its range on the interactive map→
IberáArgentina
Pantanal MatogrossenseBrazil
Noel Kempff MercadoBolivia
Bahuaja-SonenePeru
Pre-DeltaArgentina
BrocketsLeast Concern

Brockets

Subulo gouazoubira

Pampas DeerNear Threatened

Pampas Deer

Ozotoceros bezoarticus

Lowland TapirVulnerable

Lowland Tapir

Tapirus terrestris

Hyacinth MacawVulnerable

Hyacinth Macaw

Anodorhynchus hyacinthinus

Vulnerable

Pudus

Pudella mephistophiles

White-Tailed DeerLeast Concern

White-Tailed Deer

Odocoileus virginianus

CountriesArgentina
ParksIberáArgentina
TagsHerbivore
Herbivore
Crepuscular
Solitary
Vulnerable
Freshwater
Grassland
Mammal
Argentina
Bolivia
Brazil
Peru
Chile
Falkland Islands
Paraguay
Uruguay