Sea Cows | Sirenia

Sea Cows | Sirenia

Description
Description

Sea cows, belonging to the order Sirenia, are large, aquatic mammals that include manatees and dugongs. These gentle giants are known for their slow, graceful swimming and are often called "sea cows" due to their herbivorous diet, grazing on sea grasses and algae. Sirenians inhabit warm coastal waters, rivers, and estuaries primarily in the Atlantic Ocean and the Indo-Pacific region. They evolved from four-legged land mammals over 50 million years ago, adapting to a fully aquatic life. Their closest living relatives are elephants. Unfortunately, all sirenian species are currently threatened or endangered, primarily due to habitat loss, entanglement in fishing gear, and collisions with boats.

Anatomy
Anatomy

Sea cows are aquatic mammals with a stout, streamlined body, adapted for their marine existence. They possess a paddle-shaped tail and flippers to help them glide gracefully through the water. Lacking dorsal fins, their skin is thick and wrinkly, often hosting small plants and barnacles. They have a flexible, bristled upper lip aiding in feeding on sea grasses. Their ears are small, eyesight is limited, but they have a good sense of touch and hearing. Sea cows don't have vocal cords, yet they communicate through squeaks, chirps, and whistles, especially between mothers and calves.

Human Interaction
Human Interaction

The relationship between humans and Sirenia, commonly known as sea cows, is a mix of enchantment and impact. Historically, some cultures hunted them for meat and oil, while others revered them, inspiring mermaid myths. Today, they're often featured in documentaries and conservation campaigns, capturing public affection with their gentle demeanor.

Unfortunately, human activities like coastal development, water pollution, and boat traffic pose significant threats to their survival. Conservation efforts, including protected areas, boat speed regulations, and public awareness campaigns, aim to safeguard their habitats. Internationally, they're protected under agreements like the Convention on International Trade in Endangered Species (CITES).

Common Questions
Common Questions
What are the characteristics of Sirenia?

The characteristics of Sirenia include having a robust body form as well as thick skin with very little hair. Sirenia also have 2 nostrils either at the top or front of their muzzle. Sirenia have no ear pinnae as well as no hind limbs and a horizontally flattened tail.

How do Sirenia obtain food?

Sirenians are vegetarians and obtain food by feeding on seagrasses as well as other marine plants. Sirenians gather food by being bottom-feeders and typically eat only what lives on the ocean floor while others feed by swimming from the water’s surface to the bottom of the water’s floor.

What is the greatest threat on Sirenia?

The greatest threats on Sirenia include human activities such as hunting, killing fishers, as well as collisions with boats and ships. Natural factors that are threats to Sirenia include predation, severe climatic events, infectious diseases, and microparasites. All these factors serve as threats to the Sirenian population.

Animals

* Under Development *

1.6’-2’ | 50-62 cm
2.1’-2.7’ | 63-83 cm
8’-10’ | 2.4-3 m
573-1,058 lb | 260-480 kg
15-30 years
Amazonian Manatee
62.000
83.000
300.000
480.000
30.00
3900
GUIDE
3D
Amazonian Manatee
Dugong
302300
1.9’-3.1’ | 58-95 cm
3’-5’ | 93-153 cm
8’-13’ | 2.4-4 m
507-838 lb | 230-380 kg
50-70 years
Dugong
95.000
153.000
400.000
380.000
70.00
302300
GUIDE
3D
Dugong
6.5’-7.4’ | 200-225 cm
6.5’-7.4’ | 200-225 cm
26’-30’ | 7.9-9.1 m
16,000-20,000 lb | 7,260-9,070 kg
50-80 years
Steller's Sea Cow
225.000
225.000
910.000
9070.000
80.00
4700
GUIDE
3D
Steller's Sea Cow
2.1’-2.8’ | 65-85 cm
2.8’-3.6’ | 85-110 cm
10’-13’ | 3-4 m
794-1,653 lb | 360-750 kg
20-30 years
West African Manatee
85.000
110.000
400.000
750.000
30.00
260
GUIDE
3D
West African Manatee
2.3’-3.5’ | 70-107 cm
2.8’-4.3’ | 85-130 cm
10’-14.75’ | 3-4.5 m
794-1,190 lb | 360-540 kg
25-30 years
West Indian Manatee
107.000
130.000
450.000
540.000
30.00
5200
GUIDE
3D
West Indian Manatee
West African Manatee (Trichechus senegalensis)
Dimensioned comparison drawing of the West African Manatee compared to other sea cows and a person

The West African Manatee, known scientifically as Trichechus senegalensis, is the least well-known Trichechus manatee and can live in salt, brackish, or fresh waters along the western coast of Africa. The West African Manatee prefers calm waters and can usually be found grazing on sea grass in mangroves and lagoons. The West African Manatee is regarded as vulnerable by the IUCN due largely to human effects on the species. The West African Manatee is frequently killed as bycatch or hunted as a pest as it will sometimes steal fish out of nets or rice from fields. The West African Manatee is one of three manatee species that make up the family Trichechus, along with the Amazonian Manatee and the West Indian Manatee.

West African Manatees have a total length between 10’-13’ (3-4 m), body height of 2.1’-2.8’ (65-85 cm), and width of 2.8’-3.6’ (85-110 cm). The typical weight of the West African Manatee is in the range of 794-1,653 lb (360-750 kg). West African Manatee have lifespans between 20-30 years.

Set of scaled elevation drawings of the West African Manatee viewed from the front and side
The West African Manatee, known scientifically as Trichechus senegalensis, is the least well-known Trichechus manatee and can live in salt, brackish, or fresh waters along the western coast of Africa. The West African Manatee prefers calm waters and can usually be found grazing on sea grass.

West African Manatees have a total length between 10’-13’ (3-4 m), body height of 2.1’-2.8’ (65-85 cm), and width of 2.8’-3.6’ (85-110 cm). The typical weight of the West African Manatee is in the range of 794-1,653 lb (360-750 kg). West African Manatee have lifespans between 20-30 years.

Set of scaled elevation drawings of the West African Manatee viewed from the front and side
West African Manatee (Trichechus senegalensis)
Height:
2.1’-2.8’ | 65-85 cm
Width:
2.8’-3.6’ | 85-110 cm
Length:
10’-13’ | 3-4 m
Depth:
Weight:
794-1,653 lb | 360-750 kg
Area:
Scientific Name
Trichechus senegalensis
Lifespan
20-30 years

Drawings include:

West African Manatee side elevation, front, top

Downloads

2D Downloads

3D Downloads

Steller's Sea Cow (Hydrodamalis gigas)
Dimensioned comparison drawing of the Steller's Sea Cow compared to other sea cows and a person

Steller’s Sea Cow, known scientifically as Hydrodamalis gigas, was a large, slow-moving, marine mammal that was hunted to extinction for its hide, meat, and blubber in the 18th century. Much of what is known about Steller’s Sea Cow is from observations made by Georg Wilhelm Steller when an sea expedition he was on shipwrecked on Bering Island giving him time to observe this creature in its natural habitat, the Bering Sea. Before modern times, the Steller’s Sea Cow is believed to have lived all across the Pacific ocean, but then had its habitat constricted due to the glacial cycle. The Steller’s Sea Cow’s only living relative is the much smaller dugong, which is considered vulnerable to extinction by the IUCN.

Steller's Sea Cows had a total length between 26’-30’ (7.9-9.1 m), body height of 6.5’-7.4’ (200-225 cm), and width of 6.5’-7.4’ (200-225 cm). The typical weight of the Steller's Sea Cow was in the range of 16,000-20,000 lb (7,260-9,070 kg). Steller's Sea Cow had lifespans between 50-80 years.

Set of scaled elevation drawings of the Steller's Sea Cow viewed from the front and side
Steller’s Sea Cow, known scientifically as Hydrodamalis gigas, was a large, slow-moving, marine mammal that was hunted to extinction for its hide, meat, and blubber in the 18th century. Much of what is known about Steller’s Sea Cow is from observations made by Georg Wilhelm Steller.

Steller's Sea Cows had a total length between 26’-30’ (7.9-9.1 m), body height of 6.5’-7.4’ (200-225 cm), and width of 6.5’-7.4’ (200-225 cm). The typical weight of the Steller's Sea Cow was in the range of 16,000-20,000 lb (7,260-9,070 kg). Steller's Sea Cow had lifespans between 50-80 years.

Set of scaled elevation drawings of the Steller's Sea Cow viewed from the front and side
Steller's Sea Cow (Hydrodamalis gigas)
Height:
6.5’-7.4’ | 200-225 cm
Width:
6.5’-7.4’ | 200-225 cm
Length:
26’-30’ | 7.9-9.1 m
Depth:
Weight:
16,000-20,000 lb | 7,260-9,070 kg
Area:
Scientific Name
Hydrodamalis gigas
Lifespan
50-80 years

Drawings include:

Steller's Sea Cow side elevation, front, top

Downloads

2D Downloads

3D Downloads

Amazonian Manatee (Trichechus inunguis)
Measured comparison illustration of the size of a Amazonian Manatee to a typical person and sea cows

The Amazonian Manatee, known as Trichechus inunguis, is the smallest manatee and the only manatee that lives solely in freshwater tributaries. The Amazonian Manatee also has smoother, rubber-like skin when compared to the other, hairier manatees. The Amazonian Manatee is considered vulnerable by the IUCN as its population is believed to be decreasing due mainly to illegal hunting by local communities and natural predators, such as jaguars, sharks, and crocodiles. The Amazonian Manatee, like other manatees, grazes on sea grass for food, and similarly to the West Indian Manatee, communicates by vocalizing. The Amazonian Manatee has an average life span of 30 years.

Amazonian Manatees have a total length between 8’-10’ (2.4-3 m), body height of 1.6’-2’ (50-62 cm), and width of 2.1’-2.7’ (63-83 cm). The typical weight of the Amazonian Manatee is in the range of 573-1,058 lb (260-480 kg). Amazonian Manatee have lifespans between 15-30 years.

Scaled collection of drawings of Amazonian Manatee in front and side poses
The Amazonian Manatee, known as Trichechus inunguis, is the smallest manatee and the only manatee that lives solely in freshwater tributaries. The Amazonian Manatee also has smoother, rubber-like skin when compared to the other, hairier manatees. The Amazonian Manatee is considered vulnerable.

Amazonian Manatees have a total length between 8’-10’ (2.4-3 m), body height of 1.6’-2’ (50-62 cm), and width of 2.1’-2.7’ (63-83 cm). The typical weight of the Amazonian Manatee is in the range of 573-1,058 lb (260-480 kg). Amazonian Manatee have lifespans between 15-30 years.

Scaled collection of drawings of Amazonian Manatee in front and side poses
Amazonian Manatee (Trichechus inunguis)
Height:
1.6’-2’ | 50-62 cm
Width:
2.1’-2.7’ | 63-83 cm
Length:
8’-10’ | 2.4-3 m
Depth:
Weight:
573-1,058 lb | 260-480 kg
Area:
Scientific Name
Trichechus inunguis
Lifespan
15-30 years

Drawings include:

Amazonian Manatee side elevation, front, top

Downloads

2D Downloads

3D Downloads

West Indian Manatee (Trichechus manatus)
Scale illustration of an average West Indian Manatee with dimensions length compared to a human and sea cows

The West Indian Manatee, known scientifically as Trichechus manatus, is a grey and brown marine mammal with a paddle shaped tail and front flippers found in the warm salt waters between southeastern United States, Mexico, and Central America. The West Indian Manatee is considered threatened by the IUCN, but has increased its recorded population numbers from 1,267 manatees in Florida in 1991 to 6,300 currently, showing that recovery plans for this species are working. The West Indian Manatee grazes on seagrass and prefers waters above 68 degrees Fahrenheit, thus confining them to warm Floridan waters in the winter. However, during the summer the manatee has been seen as far north as Massachusetts and as far west as Texas.

West Indian Manatees have a total length between 10’-14.75’ (3-4.5 m), body height of 2.3’-3.5’ (70-107 cm), and width of 2.8’-4.3’ (85-130 cm). The typical weight of the West Indian Manatee is in the range of 794-1,190 lb (360-540 kg). West Indian Manatee have lifespans between 25-30 years.

Pair of elevation illustrations of the West Indian Manatee seen from the side and front
The West Indian Manatee, known scientifically as Trichechus manatus, is a grey and brown marine mammal with a paddle shaped tail and front flippers found in the warm salt waters between southeastern United States, Mexico, and Central America. The West Indian Manatee is considered threatened.

West Indian Manatees have a total length between 10’-14.75’ (3-4.5 m), body height of 2.3’-3.5’ (70-107 cm), and width of 2.8’-4.3’ (85-130 cm). The typical weight of the West Indian Manatee is in the range of 794-1,190 lb (360-540 kg). West Indian Manatee have lifespans between 25-30 years.

Pair of elevation illustrations of the West Indian Manatee seen from the side and front
West Indian Manatee (Trichechus manatus)
Height:
2.3’-3.5’ | 70-107 cm
Width:
2.8’-4.3’ | 85-130 cm
Length:
10’-14.75’ | 3-4.5 m
Depth:
Weight:
794-1,190 lb | 360-540 kg
Area:
Scientific Name
Trichechus manatus
Lifespan
25-30 years

Drawings include:

West Indian Manatee side elevation, front, top

Downloads

2D Downloads

3D Downloads

Dugong (Dugong dugon)
Measured comparison illustration of the size of a Dugong to a typical person and sea cows

The Dugong, known scientifically as Dugong dugon, is a marine mammal that is part of the order Sirenia, which includes three other types of manatees. Due to anthropogenic causes, the Dugong is considered a vulnerable species by the IUCN and is the last remaining member of the Dugongidae family. The Dugong’s most recent relative was the Steller’s sea cow, which was declared extinct in the 18th century. The Dugong can be found throughout the waters of the Indo-Pacific ocean grazing on seagrass. The Dugong, similar in body shape to other manatees, has no dorsal fins or hind limbs and has paddle shaped flippers; however, the Dugong has a fluked tail, which is more similar to a dolphin.

Dugongs have a total length between 8’-13’ (2.4-4 m), body height of 1.9’-3.1’ (58-95 cm), and width of 3’-5’ (93-153 cm). The typical weight of the Dugong is in the range of 507-838 lb (230-380 kg). Dugong have lifespans between 50-70 years.

Scaled collection of drawings of Dugong in front and side poses
The Dugong, known scientifically as Dugong dugon, is a marine mammal that is part of the order Sirenia, which includes three other types of manatees. Due to anthropogenic causes, the Dugong is considered a vulnerable species by the IUCN and is the last remaining member of the Dugongidae family.

Dugongs have a total length between 8’-13’ (2.4-4 m), body height of 1.9’-3.1’ (58-95 cm), and width of 3’-5’ (93-153 cm). The typical weight of the Dugong is in the range of 507-838 lb (230-380 kg). Dugong have lifespans between 50-70 years.

Scaled collection of drawings of Dugong in front and side poses
Dugong (Dugong dugon)
Height:
1.9’-3.1’ | 58-95 cm
Width:
3’-5’ | 93-153 cm
Length:
8’-13’ | 2.4-4 m
Depth:
Weight:
507-838 lb | 230-380 kg
Area:
Scientific Name
Dugong dugon
Lifespan
50-70 years

Drawings include:

Dugong side elevation, front, top

Downloads

2D Downloads

3D Downloads