Forest

Habitats

Forest

  • 1.1. Boreal
  • 1.2. Subarctic
  • 1.3. Subantarctic
  • 1.4. Temperate
  • 1.5. Subtropical/tropical dry
  • 1.6. Subtropical/tropical moist lowland
  • 1.7. Subtropical/tropical mangrove vegetation above high tide level
  • 1.8. Subtropical/tropical swamp
  • 1.9. Subtropical/tropical moist montane

 

Forest Animals

North America

Continents

North America

 

North American Animals

Savanna

Habitats

Savanna

  • 2.1. Dry
  • 2.2. Moist

 

Savanna Animals

Europe

Continents

Europe

 

European Animals

Asia

Continents

Asia

 

Asian Animals

Shrubland

Habitats

Shrubland

  • 3.1. Subarctic
  • 3.2. Subantarctic
  • 3.3. Boreal
  • 3.4. Temperate
  • 3.5. Subtropical/tropical dry
  • 3.6. Subtropical/tropical moist
  • 3.7. Subtropical/tropical high altitude
  • 3.8. Mediterranean-type shrubby vegetation

 

Shrubland Animals

Grassland

Habitats

Grassland

  • 4.1. Tundra
  • 4.2. Subarctic
  • 4.3. Subantarctic
  • 4.4. Temperate
  • 4.5. Subtropical/tropical dry
  • 4.6. Subtropical/tropical seasonally wet/flooded
  • 4.7. Subtropical/tropical high altitude

 

Grassland Animals

South America

Continents

South America

 

South American Animals

Wetlands

Habitats

Wetlands (Inland)

  • 5.1. Permanent rivers/streams/creeks (includes waterfalls)
  • 5.2. Seasonal/intermittent/irregular rivers/streams/creeks
  • 5.3. Shrub dominated wetlands
  • 5.4. Bogs, marshes, swamps, fens, peatlands
  • 5.5. Permanent freshwater lakes (over 8 ha)
  • 5.6. Seasonal/intermittent freshwater lakes (over 8 ha)
  • 5.7. Permanent freshwater marshes/pools (under 8 ha)
  • 5.8. Seasonal/intermittent freshwater marshes/pools (under 8 ha)
  • 5.9. Freshwater springs and oases
  • 5.10. Tundra wetlands (inc. pools and temporary waters from snowmelt)
  • 5.11. Alpine wetlands (inc. temporary waters from snowmelt)
  • 5.12. Geothermal wetlands
  • 5.13. Permanent inland deltas
  • 5.14. Permanent saline, brackish or alkaline lakes
  • 5.15. Seasonal/intermittent saline, brackish or alkaline lakes and flats
  • 5.16. Permanent saline, brackish or alkaline marshes/pools
  • 5.17. Seasonal/intermittent saline, brackish or alkaline marshes/pools
  • 5.18. Karst and other subterranean hydrological systems (inland)

 

Wetland Animals

Africa

Continents

Africa

 

African Animals

Rocky

Habitats

Rocky

  • Inland Cliffs
  • Mountain Peaks

 

Rocky Area Animals

Australia

Continents

Australia

 

Australian Animals

Antarctica

Continents

Antarctica

 

Antarctic Animals

Caves & Subterranean

Habitats

Caves & Subterranean (Non-Aquatic)

  • 7.1. Caves
  • 7.2. Other subterranean habitats

 

Caves & Subterranean Animals

Desert

Habitats

Desert

  • 8.1. Hot
  • 8.2. Temperate
  • 8.3. Cold

 

Desert Animals

Marine Neritic

Habitats

Marine Neritic

  • 9.1. Pelagic
  • 9.2. Subtidal rock and rocky reefs
  • 9.3. Subtidal loose rock/pebble/gravel
  • 9.4. Subtidal sandy
  • 9.5. Subtidal sandy-mud
  • 9.6. Subtidal muddy
  • 9.7. Macroalgal/kelp
  • 9.8. Coral Reef
    • 9.8.1. Outer reef channel
    • 9.8.2. Back slope
    • 9.8.3. Foreslope (outer reef slope)
    • 9.8.4. Lagoon
    • 9.8.5. Inter-reef soft substrate
    • 9.8.6. Inter-reef rubble substrate
  • 9.9 Seagrass (Submerged)
  • 9.10 Estuaries

 

Marine Neritic Animals

Marine Oceanic

Habitats

Marine Oceanic

  • 10.1 Epipelagic (0–200 m)
  • 10.2 Mesopelagic (200–1,000 m)
  • 10.3 Bathypelagic (1,000–4,000 m)
  • 10.4 Abyssopelagic (4,000–6,000 m)

 

Marine Oceanic Animals

Marine Deep Ocean Floor

Habitats

Marine Deep Ocean Floor (Benthic and Demersal)

  • 11.1 Continental Slope/Bathyl Zone (200–4,000 m)
    • 11.1.1 Hard Substrate
    • 11.1.2 Soft Substrate
  • 11.2 Abyssal Plain (4,000–6,000 m)
  • 11.3 Abyssal Mountain/Hills (4,000–6,000 m)
  • 11.4 Hadal/Deep Sea Trench (>6,000 m)
  • 11.5 Seamount
  • 11.6 Deep Sea Vents (Rifts/Seeps)

 

Marine Deep Ocean Floor Animals

Marine Intertidal

Habitats

Marine Intertidal

  • 12.1 Rocky Shoreline
  • 12.2 Sandy Shoreline and/or Beaches, Sand Bars, Spits, etc.
  • 12.3 Shingle and/or Pebble Shoreline and/or Beaches
  • 12.4 Mud Shoreline and Intertidal Mud Flats
  • 12.5 Salt Marshes (Emergent Grasses)
  • 12.6 Tidepools
  • 12.7 Mangrove Submerged Roots

 

Marine Intertidal Animals

Marine Coastal/Supratidal

Habitats

Marine Coastal/Supratidal

  • 13.1 Sea Cliffs and Rocky Offshore Islands
  • 13.2 Coastal Caves/Karst
  • 13.3 Coastal Sand Dunes
  • 13.4 Coastal Brackish/Saline Lagoons/Marine Lakes
  • 13.5 Coastal Freshwater Lakes

 

Marine Coastal/Supratidal Animals

Artificial Terrestrial

Habitats

Artificial – Terrestrial

  • 14.1 Arable Land
  • 14.2 Pastureland
  • 14.3 Plantations
  • 14.4 Rural Gardens
  • 14.5 Urban Areas
  • 14.6 Subtropical/Tropical Heavily Degraded Former Forest

 

Artificial Terrestrial Animals

Artificial Aquatic

Habitats

Artificial – Aquatic

  • 15.1 Water Storage Areas [over 8 ha]
  • 15.2 Ponds [below 8 ha]
  • 15.3 Aquaculture Ponds
  • 15.4 Salt Exploitation Sites
  • 15.5 Excavations (open)
  • 15.6 Wastewater Treatment Areas
  • 15.7 Irrigated Land [includes irrigation channels]
  • 15.8 Seasonally Flooded Agricultural Land
  • 15.9 Canals and Drainage Channels, Ditches
  • 15.10 Karst and Other Subterranean Hydrological Systems [human-made]
  • 15.11 Marine Anthropogenic Structures
  • 15.12 Mariculture Cages
  • 15.13 Mari/Brackish-culture Pond

 

Artificial Aquatic
Habitats

Introduced Vegetation

 

Introduced Vegetation Animals

Other

Other

 

Other Habitat Animals

Unknown

Unknown

 

Unknown Habitat Animals

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Sea Otter

Sea Otter

Sea otters are one of several species of mammals that undergo delayed implantation that allows for birth under favorable conditions and produces varied gestation times.

Sea otters are one of several species of mammals that undergo delayed implantation in which the embryo does not implant during the immediate period following fertilization, but remains in a state of suspended growth allowing for birth to occur under favorable conditions.

Delayed implantation produces varied gestation times, which has been reported as 4 to 12 months.

Orientation of the fetus may be either caudal or cephalic, although cephalic orientation is more common near birth.


Image |©️ Tony’s Takes, Some Rights Reserved(CC BY-NC-ND 2.0)
Sources | (Allegra & Gunderson 2012; Estes, 1980; McShane, Estes, Riedman, & Staedler, 1995; Nowak, 1999; Riedman, Estes, Staedler, Giles, & Carlson, 1994)br>

 

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Sea Otter

Sea Otter

Because sea otter’s don’t have insulating fat, their reddish brown fur consists of two layers and is the densest of all mammals with about 100,000 hairs/cm².

The sea otter’s pelage is brown or reddish brown.

Sea otter fur is the densest of all mammals, with about 100,000 hairs per square centimeter. Because sea otters do not have any insulating fat, the fur is responsible for heat maintenance. The fur consists of two layers: a dark undercoat and longer, lighter-colored guard hairs, which trap a layer of air next to the skin to keep it dry.

Sea otters diligently groom and clean their fur to maintain its insulating ability. Female sea otters groom their pups extensively for 3 months as their coat develops.


Image |©️ Andrew Smarius, Some Rights Reserved Unsplash
Sources | (Allegra & Gunderson 2012; Cohn, 1998; Estes, 1980; Estes, Underwood, & Karmann, 1986; Fisher, 1939; Limbaugh, 1961; Lockwood, 2006; Nowak, 1999; Paine, 1993)br>

 

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Sea Otter

Sea Otter

Starting at 2 months of age, sea otters are capable of diving to depths of at least 45 m., but prefer coastal waters up to 30 m. deep to find food easier.

While sea otters are capable of diving to depths of at least 45 meters, they prefer coastal waters up to 30 meters deep. The shallower the water, the less time is spent diving to reach food.

Pups start diving at 2 months of age.


Image |©️ Abigail Lynn, Some Rights ReservedUnsplash
Sources | (Allegra & Gunderson 2012; Estes, 1980; Lockwood, 2006; Nowak, 1999; Paine, 1993)br>

 

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Sea Otter

Sea Otter

Cat and opossum feces travel to storm drains via runoff and toilet disposal, eventually coming into contact with sea otters and infecting them with deadly apicomplexan protozoan parasites that cause encephalitis.

Parasites and infectious disease contribute to sea otter mortality, specifically Toxoplasma gondii, which infects domestic cats (Felis catus), and Sarcosystis neurona, which infects opossums. These apicomplexan protozoan parasites infect the sea otter and cause encephalitis. It is postulated that cat and opossum feces travel to storm drains via runoff and disposal in toilets, eventually coming into contact with sea otters.

In September 2006, Governor Arnold Schwarzenegger passed a law raising the maximum fine for harming a sea otter to $25,000, and required that all cat litter sold in California display a warning label that advises not to dump cat feces down storm drains or in toilets.

An acanthocephalen worm (Profilicollis) has also been linked to mortality and decline in the sea otter population.


Image |©️ Sab_k, Some Rights ReservedPixabay
Sources | (Allegra & Gunderson 2012; Cohn, 1998; Cray, 2006; Doroff & Burdin, 2011; Estes, 1980; Estes & Duggins, 1995; Estes & Palmisano, 1974; Estes, et al., 1978; Jessup, et al., 2004; Nowak, 1999)
br>

 

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Sea Otter

Sea Otter

Sea otters communicate with 9 vocalizations and each otter has its own distinct scent that convey identity, age, and sex.

Sea otters communicate through body contact, scent, and vocalizations, although they are not overly vocal.

Researchers have recognized nine vocalizations. Pups use squeals to communicate with their mothers. Other calls include coos, whines, distress screams, growls, snarls, and whistles.

Scent is important in recognition and surveying physiological states. Each sea otter has its own distinct scent that conveys identity, age, and sex.


Image |©️ Andrew Reding, Some Rights Reserved(CC BY-NC-ND 2.0)
Sources | (Allegra & Gunderson 2012)br>

 

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Sea Otter

Sea Otter

The maximum estimated lifespan of sea otters is 23 years in the wild.

Sea otters are long-lived. The maximum estimated lifespan of sea otters is 23 years in the wild.


Image |©️ Josh More, Some Rights Reserved(CC BY-NC-ND 2.0)
Sources | (Allegra & Gunderson 2012; Cohn, 1998; Estes, 1980; Estes, Underwood, & Karmann, 1986; Fisher, 1939; Limbaugh, 1961; Nowak, 1999; Paine, 1993)br>

 

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Sea Otter

Sea Otter

Sea otters consume 20-25% of their body weight each day, eating 3-4 times a day, and tend to be specialized in their choice of prey.

Sea otters consume 20 to 25% of their body weight each day and usually eat 3 to 4 times a day. They obtain most of their water from prey but also drink seawater to satisfy thirst.

Sea otter individuals tend to be specialized in their choice of prey. One otter may consume only urchins and crabs while another may eat mostly fish, depending on the abilities of the individual and local food availability.


Image |©️ Ashley_Murphy, Some Rights Reserved(CC BY-NC-ND 2.0)
Sources | (Allegra & Gunderson 2012; Cohn, 1998; Estes, 1980; Estes, Underwood, & Karmann, 1986; Fisher, 1939; Limbaugh, 1961; Nowak, 1999; Paine, 1993)br>

 

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Sea Otter

Sea Otter

Sea otters are polygynous, with males having multiple female partners throughout the year.

Sea otters are polygynous, with males having multiple female partners throughout the year. Males mate with females that inhabit their territory. If no territory is established, they seek out females in estrus.

Females reach sexual maturity at 4 years of age. Males reach sexual maturity at 5 to 6 years, but may not mate until much later.


Image |©️ Anita Ritenour, Some Rights Reserved(CC BY-NC-ND 2.0)
Sources | (Allegra & Gunderson 2012; Estes, 1980; McShane, Estes, Riedman, & Staedler, 1995; Nowak, 1999; Riedman, Estes, Staedler, Giles, & Carlson, 1994)br>

 

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Sea otters are polygynous, with males having multiple female partners throughout the year.

Sea Otter

Sea Otter

Because male sea otters hold the female’s head or nose with their jaws during copulation, many females have visible face scars.

When a male sea otter finds a receptive female, the two bond for the duration of estrus, or 3 days.

The couple engages in playful and sometimes aggressive behavior. The male holds the female’s head or nose with his jaws during copulation. Visible scars are often present on females from this behavior.


Image |©️ Andrew Reding, Some Rights Reserved(CC BY-NC-ND 2.0)
Sources | (Allegra & Gunderson 2012; Estes, 1980; McShane, Estes, Riedman, & Staedler, 1995; Nowak, 1999)br>

 

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Sea Otter

Sea Otter

Sea otters are diurnal with crepuscular peaks in foraging activity and spend 15-55% of their time foraging, depending on food availability.

Sea otters are diurnal with crepuscular peaks in foraging activity.

Sea otters spend 15 to 55% of their time foraging, depending on food availability. Foraging dives usually last 50 to 90 seconds, but otters can remain submerged for nearly 6 minutes.

The sea otter feeding process, including foraging, eating, and cleaning their fur after a meal, lasts 2 to 3 hours and sea otters tend to eat 3 to 4 times a day.


Image |©️ Rich Miller, Some Rights Reserved(CC BY-NC-ND 2.0)
Sources | (Allegra & Gunderson 2012; Cohn, 1998; Estes, 1980; Estes, Underwood, & Karmann, 1986; Fisher, 1939; Limbaugh, 1961; Nowak, 1999; Paine, 1993)br>

 

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Sea Otter

Sea Otter

Although twins occur in 2% of sea otters births, only one pup can be raised successfully.

Twins occur in 2% of sea otter births, but only one pup can be raised successfully.

If a pup does not survive, the mother may experience postpartum estrus.


Image |©️ Tony’s Takes, Some Rights Reserved(CC BY-NC-ND 2.0)
Sources | (Allegra & Gunderson 2012; Estes, 1980; McShane, Estes, Riedman, & Staedler, 1995; Nowak, 1999; Riedman, Estes, Staedler, Giles, & Carlson, 1994)br>

 

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Sea Otter

Sea Otter

Male sea otters don’t provide any care for their offspring while the females nurse, feed, protect, and groom the young for up to 6-8 months.

Male sea otters do not provide any care for their offspring.

While a mother is foraging, she wraps her pup in kelp at the water surface to keep it from drifting away. At any sign of a predator, the female clamps onto her pup’s neck with her mouth and dives.

Female sea otters groom their pups extensively for 3 months as their coat develops. A pup’s coat traps air, which keeps the animal afloat.

Pups start diving at 2 months of age. The pup typically remains dependent on the mother for about 6 to 8 months after birth.


Image |©️ Karen Hall, Some Rights Reserved(CC BY-NC-ND 2.0)
Sources | (Allegra & Gunderson 2012; Estes, 1980; Lockwood, 2006; Nowak, 1999; Paine, 1993)br>

 

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Sea Otter

Sea Otter

Female sea otters carry their pups on their bellies while they nurse, providing their young with 20-25% fat milk for up to 6 months.

Female sea otters carry their pups on their bellies while they nurse. They have two mammae and their milk is 20 to 25% fat. Pups are weaned at around 6 months of age but start to eat solid foods shortly after birth.


Image |©️ Anchor Lee, Some Rights ReservedUnsplash
Sources | (Allegra & Gunderson 2012; Estes, 1980; Lockwood, 2006; Nowak, 1999; Paine, 1993)br>

 

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Sea Otter

Sea Otter

Because sea otter fur is coveted for its density and insulating quality, sea otters were nearly hunted to extinction from the mid 1700’s to 1911 when the International Fur Seal Treaty was enacted.

The fur of sea otters was of great importance in the fur trade from the mid 1700’s to 1911. Hunting during the 18th and 19th centuries has greatly reduced the distribution of sea otters. Sea otters were hunted to near extinction (1,000 to 2,000 individuals worldwide) at until the turn of the 20th century when the United States, Russia, Japan, and Great Britain reached an agreement in 1911 called the International Fur Seal Treaty, banning the hunting of fur-bearing sea mammals. In 1972, the U.S. Marine Mammal Protection Act offered further protection by banning capture and harassment of sea mammals.

Sea otter fur was coveted due to its extreme density and insulating quality. Pelts sold for as much as $1,125 each and were fashioned into hats, coats, and other garments sold in Russia, Canada, and the United States.


Image |©️ Christels, Some Rights ReservedPixabay
Sources | (Allegra & Gunderson 2012; Cray, 2006; Estes, 1980; Lockwood, 2006; Nowak, 1999; Wilson, Bogan, Brownwell, Burdin, & Maminov, 1991)br>

 

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Sea Otter

Sea Otter

Female sea otters usually give birth to a single pup about once a year at any time, though there are peaks of birth in May-June in the Aleutian Islands and in January-March in California.

Sea otters can reproduce year round, though there are peaks of birth in May to June in the Aleutian Islands and in January to March in California.

Females usually give birth about once a year, though many females experience longer breeding intervals, giving birth every 2 years. A single pup is born weighing 1.4 to 2.3 kilograms.


Image |©️ Andrew Reding, Some Rights Reserved/(CC BY-NC-ND 2.0)
Sources | (Allegra & Gunderson 2012; Estes, 1980; McShane, Estes, Riedman, & Staedler, 1995; Nowak, 1999; Riedman, Estes, Staedler, Giles, & Carlson, 1994)br>

 

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Sea Otter

Sea Otter

Sea ice limits the sea otter’s northern range while the distribution of giant kelp forests limits its southern range.

Sea ice limits the sea otter’s northern range to below 57 degrees North latitude, and the distribution of giant kelp (Macrocystis pyrifera) forests limits the southern range to about 22 degrees North latitude.


Image |©️ Tony’s Takes, Some Rights Reserved(CC BY-NC-ND 2.0)
Sources | (Allegra & Gunderson 2012; Estes, 1980; Lockwood, 2006; Nowak, 1999; Wilson, Bogan, Brownwell, Burdin, & Maminov, 1991)br>

 

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Sea Otter

Sea Otter

Sea otters are found in two geographic regions on the Pacific Coast around Canada, the United States, and Mexico in North America and around Russia and Japan in Asia.

Sea otters are found in two geographic regions on the Pacific Coast: along the Kuril and Commander Islands off the coast of Russia, the Aleutian Islands below the Bering Sea, and the coastal waters off the Alaskan Peninsula to Vancouver Island, Canada; and along the central California coast from Ano Nuevo to Point Sur.


Image ©️ 272447, Some Rights Reserved/Pixabay
Sources | (Allegra & Gunderson 2012; Estes, 1980; Lockwood, 2006; Nowak, 1999; Wilson, Bogan, Brownwell, Burdin, & Maminov, 1991)br>

 

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Sea Otter Trivia

Sea Otter

Do you think you know the sea otter? Test your knowledge of sea otter FaunaFacts with this trivia quiz!

Click on an answer choice to receive instant feedback. Red answers are incorrect, but allow you to continue guessing. Green answers are correct and will provide additional explanatory information. Sometimes more than one answer is correct!

Learn More About the Sea Otter | Play on Quizizz


What is the sea otter’s population trend?
Decreasing
According to the Otter Foundation, the California sea otter population declined from July 2008 to July 2011. Estimates suggest a California population of approximately 2,700 individuals.
Increasing
Stable
Unknown

How do sea otters contribute to the ecosystem?
Control Herbivorous Invertebrates
Sea otters are considered a keystone species and play a major role in the community by controlling herbivorous invertebrates. Sea otters prey on sea urchins, thereby preventing sea urchins from overgrazing the kelp forest. This allows the kelp forest to thrive and contributes to an increase in marine diversity.
Prevent Overgrazing of Kelp
Sea otters are considered a keystone species and play a major role in the community by controlling herbivorous invertebrates. Sea otters prey on sea urchins, thereby preventing sea urchins from overgrazing the kelp forest. This allows the kelp forest to thrive and contributes to an increase in marine diversity.
Increase Marine Diversity
Sea otters are considered a keystone species and play a major role in the community by controlling herbivorous invertebrates. Sea otters prey on sea urchins, thereby preventing sea urchins from overgrazing the kelp forest. This allows the kelp forest to thrive and contributes to an increase in marine diversity.
Improve Water Quality

What limits the sea otter’s southern range?
Giant Kelp
The distribution of giant kelp (Macrocystis pyrifera) forests limits the southern range to about 22 degrees North latitude.
Temperature
Great White Sharks
Sea Ice

Sea otters are sexually dimorphic.
True, males are larger.
Sea otters display sexual dimorphism as males are larger than females. Males measure 1.2 to 1.5 meters in length, while females measure 1 to 1.4 meters.
True, females are larger.
False

What continents do sea otters inhabit?
Asia
Sea otters are found in two geographic regions around Canada, the United States, and Mexico in North America and around Russia and Japan in Asia.
North America
Sea otters are found in two geographic regions on the Pacific Coast around Canada, the United States, and Mexico in North America and around Russia and Japan in Asia.
Australia
South America

How deep can sea otters dive?
45 m. / 148 ft.
Sea otters are capable of diving to depths of at least 45 meters.
25 m. / 82 ft.
35 m. / 115 ft.
15 m. / 49 ft.

When are sea otter pups weaned?
6 Months
Pups are weaned at around 6 months of age but start to eat solid foods shortly after birth.
1 Month
1 Year
3 Months

What marine habitats do sea otters inhabit?
Neritic
Sea otters inhabit marine neritic and marine oceanic habitats. They can be found in temperate coastal waters with rocky or soft sediment ocean bottom and live in offshore forests of giant kelp (Macrocystis pyrifera).
Ocenaic
Sea otters inhabit marine neritic and marine oceanic habitats. They can be found in temperate coastal waters with rocky or soft sediment ocean bottom and live in offshore forests of giant kelp (Macrocystis pyrifera).
Intertidal
Coastal/Supratidal

What is the sea otter’s mating system?
Polygyny
Sea otters are polygynous, with males having multiple female partners throughout the year.
Polyandry
Monogamy
Polygynandry

How many vocalizations do sea otters have?
9
Sea otters communicate through body contact, scent, and vocalizations, although they are not overly vocal. Researchers have recognized nine vocalizations. Pups use squeals to communicate with their mothers. Other calls include coos, whines, distress screams, growls, snarls, and whistles.
3
6
12

Why do sea otters wrap themselves in kelp?
Prevent Drifting Away
When resting or sleeping, sea otters float on their backs and wrap themselves in kelp to keep from drifting.
Regulate Body Temperature
Keep Afloat
Deter Predators

Sea otters are one of the few mammals that exhibit tool use.
True
Sea otters are one of few mammals that exhibit tool use.
False

How many subspecies of sea otter are recognized?
3
Three regional subspecies of the sea otter have been confirmed and are recognized with distinct geographical distributions.
0
2
5

What is the sea otter’s social system?
Social
Sea otters are social creatures and congregate in groups when resting.
Solitary

How does a sea otter swim?
Vertical Undulation
Sea otters utilize vertical undulations of the body to swim, tucking in the forelimbs and using the hind limbs and tail to control their motion.
Vertical Oscillation
Horizontal Undulation
Horizontal Oscillation

When is the sea otter breeding season?
Year-Round
Sea otters can reproduce year round, though there are peaks of birth in May to June in the Aleutian Islands and in January to March in California.
May-June
January-March
August-October

Sea otter fur is the densest of all mammals.
True
Sea otter fur is the densest of all mammals, with about 100,000 hairs per square centimeter.
False

How do sea otters defend their territories?
Splashing
Many males actively defend their territories. Disputes are usually settled with splashing and vocal displays, and fighting is rare.
Vocal Displays
Many males actively defend their territories. Disputes are usually settled with splashing and vocal displays, and fighting is rare.
Kelp Perimeter
Raising Body Out of Water

Sea otter individuals tend to have what type of diet?
Specialized
Sea otter individuals tend to be specialized in their choice of prey. One otter may consume only urchins and crabs while another may eat mostly fish, depending on the abilities of the individual and local food availability.
General

How does the Asian sea otter differ from other subspecies?
Wider Skull
The Asian sea otter is the largest subspecies and has a slightly wider skull and shorter nasal bones than both other subspecies. Northern sea otters are slightly larger than Californian otters. Adult male northern sea otters weigh 27 to 39 kilograms, while females weigh 16 to 27 kilograms. Adult male southern sea otters average 29 kilograms in mass, while females average 20 kilograms. Northern sea otters possess longer mandibles (lower jaws) while southern sea otters have longer rostrums and smaller teeth.
Longer Nasal Bones
Shorter
Smaller Teeth

What is the sea otter’s diet?
Carnivorous
Sea otters are carnivorous. They will eat nearly any fish or marine invertebrate they can find in their kelp forest foraging grounds. Their diet consists of marine invertebrate herbivores and filter feeders such as sea urchins (Strongylocentrotus purpuratus and Strongylocentrotus franciscanus), sea stars (Pisaster ochraceus), limpets (Diodora aspera), coast mussels (Mytilus edulis), chitons (Katharina tunicata), and purple-hinged rock scallops (Crassadoma gigantea). Otters also eat crabs, octopus, squid, and fish.
Herbivorous
Omnivorous
Unknown

Sea otter home range size varies by sex.
True, males’ are larger.
Male sea otters have larger home ranges than females. The home range of a male may overlap with that of several females.
True, females’ are larger.
False

Why was sea otter fur coveted?
Density
Sea otter fur was coveted due to its extreme density and insulating quality.
Insulating Quality
Sea otter fur was coveted due to its extreme density and insulating quality.
Color
Softness

What is the sea otter’s evaluation on the IUCN Red List of Threatened Species?
Endangered
As of 2020, the sea otter is considered Endangered by the International Union for Conservation of Nature and Natural Resources (IUCN) Red List of Threatened Species.
Critically Endangered
Extinct in the Wild
Vulnerable

Where do sea otters store their tools and food?
23 years
Sea otters are long-lived. The maximum estimated lifespan of sea otters is 23 years in the wild.
13 Years
33 Years
43 Years

What is the sea otter’s parental care?
Maternal
Male sea otters do not provide any care for their offspring, but females do.
Paternal
None
Both, Maternal & Paternal

What is the sea otter’s rhythm?
Diurnal
Sea otters are diurnal with crepuscular peaks in foraging activity.
Nocturnal
Crepuscular
Cathemeral

The feces of which animals are threatening sea otters?
Domestic Cat
Parasites and infectious disease contribute to sea otter mortality, specifically Toxoplasma gondii, which infects domestic cats (Felis catus), and Sarcosystis neurona, which infects opossums. These apicomplexan protozoan parasites infect the sea otter and cause encephalitis. It is postulated that cat and opossum feces travel to storm drains via runoff and disposal in toilets, eventually coming into contact with sea otters.
Opossum
Parasites and infectious disease contribute to sea otter mortality, specifically Toxoplasma gondii, which infects domestic cats (Felis catus), and Sarcosystis neurona, which infects opossums. These apicomplexan protozoan parasites infect the sea otter and cause encephalitis. It is postulated that cat and opossum feces travel to storm drains via runoff and disposal in toilets, eventually coming into contact with sea otters.
Domestic Dog
Rabbit

How many offspring can a sea otter raise successfully each year?
1
Only one pup can be raised successfully.
3
2
5

What purpose does the sea otter’s whiskers serve?
Find Food
Sea otters have circular, furry faces with short noses, rounded eyes and ears, and long whiskers that assist in foraging for food. Sea otters use their sensitive whiskers to locate small creatures in the dense kelp beds and crevices.
Detect Water Currents
Assist Swimming
Insulate Body Temperature

What preys on sea otters?
Great White Sharks
Great white sharks (Carcharodon carcharias) are one of the primary predators of sea otters. Otters are occasionally eaten by coyotes (Canis lantrans) after taking refuge on the sand during stormy weather. Young pups left alone on the surface while their mothers feed beneath the surface are preyed upon by bald eagles (Haliaeetus leucocephalus). It was once thought that killer whales (Orcinus orca) were responsible for declines in the sea otter population in Alaska, but evidence is inconclusive.
Killer Whales
Great white sharks (Carcharodon carcharias) are one of the primary predators of sea otters. Otters are occasionally eaten by coyotes (Canis lantrans) after taking refuge on the sand during stormy weather. Young pups left alone on the surface while their mothers feed beneath the surface are preyed upon by bald eagles (Haliaeetus leucocephalus). It was once thought that killer whales (Orcinus orca) were responsible for declines in the sea otter population in Alaska, but evidence is inconclusive.
Coyotes
Great white sharks (Carcharodon carcharias) are one of the primary predators of sea otters. Otters are occasionally eaten by coyotes (Canis lantrans) after taking refuge on the sand during stormy weather. Young pups left alone on the surface while their mothers feed beneath the surface are preyed upon by bald eagles (Haliaeetus leucocephalus). It was once thought that killer whales (Orcinus orca) were responsible for declines in the sea otter population in Alaska, but evidence is inconclusive.
Bald Eagles
Great white sharks (Carcharodon carcharias) are one of the primary predators of sea otters. Otters are occasionally eaten by coyotes (Canis lantrans) after taking refuge on the sand during stormy weather. Young pups left alone on the surface while their mothers feed beneath the surface are preyed upon by bald eagles (Haliaeetus leucocephalus). It was once thought that killer whales (Orcinus orca) were responsible for declines in the sea otter population in Alaska, but evidence is inconclusive.

What depth of water does the sea otter prefer?
Shallow
Sea otters prefer coastal waters up to 30 meters deep. The shallower the water, the less time is spent diving to reach food.
Deep

How long is a sea otter’s tail compared to its body?
1/3x
The tail comprises less than a third of the body length, measuring 25 to 35 centimeters, or 10-14 inches.
1x
1/2x
2x

What ocean does the sea otter inhabit?
Pacific
Sea otters are found in two geographic regions on the Pacific Coast.
Indian
Atlantic
Arctic

Sea otter pups can start diving at what age?
2 Months
Pups start diving at 2 months of age.
Birth
2 Weeks
1 Year

How much fat is sea otter milk?
20-25%
Sea otter milk is 20 to 25% fat.
10-15%
30-35%
40-45%

How many mammae does a female sea otter have?
2
Female sea otters have two mammae.
4
6
8

Which sex of sea otter receives face scars from mating?
Female
Sea otter couples engages in playful and sometimes aggressive behavior. The male holds the female’s head or nose with his jaws during copulation. Visible scars are often present on females from this behavior.
Male
Both, Male & Female

A sea otter’s scent can deliver what information?
Identity
Scent is important in recognition and surveying physiological states. Each sea otter has its own distinct scent that conveys identity, age, and sex.
Age
Scent is important in recognition and surveying physiological states. Each sea otter has its own distinct scent that conveys identity, age, and sex.
Sex
Scent is important in recognition and surveying physiological states. Each sea otter has its own distinct scent that conveys identity, age, and sex.
Diet

Sea otters reuse their tools.
True
Sea otters keep the same rock for many dives.
False

How does the sea otter use tools?
Breaks Prey with Rocks
Sea otters break open prey items with hard shells or exoskeletons with a rock. Some otters hold the rock on their chest and drive the prey into the rocks. Others leave the prey on their chests and hit the prey with the rocks.
Covers Face with Sponges
Picks Crevices with Sticks
Exfoliates with Tree Bark

What is the largest subspecies of sea otter?
Asian
The Asian sea otter is the largest subspecies.
Southern
Western
Northern

What is a group of sea otters called?
Bevy
Sea otters congregate in groups known as bevies, families, lodges, rafts, romps, or pods, when resting. Romp is descriptive of their playful nature, while raft is descriptive of their water-floating habits. Sea otters commonly feed in small groups.
Romp
Sea otters congregate in groups known as bevies, families, lodges, rafts, romps, or pods, when resting. Romp is descriptive of their playful nature, while raft is descriptive of their water-floating habits. Sea otters commonly feed in small groups.
Raft
Sea otters congregate in groups known as bevies, families, lodges, rafts, romps, or pods, when resting. Romp is descriptive of their playful nature, while raft is descriptive of their water-floating habits. Sea otters commonly feed in small groups.
Colony

How fast can a sea otter swim underwater?
9 kph / 6 mph
Sea otters can swim as fast as 9 kilometers per hour, or 6 miles per hour, underwater.
6 kph / 4 mph
3 kph / 2 mph
12 kph / 7.5 mph

To how many offspring does a female sea otter typically give birth?
1
A single pup is born weighing 1.4 to 2.3 kilograms.
2
3
5

How many layers does sea otter fur have?
2
The fur consists of two layers: a dark undercoat and longer, lighter-colored guard hairs, which trap a layer of air next to the skin to keep it dry.
1
3
5

Which sex of sea otter reaches sexual maturity first?
Female
Females reach sexual maturity at 4 years of age. Males reach sexual maturity at 5 to 6 years, but may not mate until much later.
Male

What percentage of their body weight do sea otters consume daily?
20-25%
Sea otters consume 20 to 25% of their body weight each day and usually eat 3 to 4 times a day.
10-15%
40-45%
30-35%

Which is the smallest sea otter subspecies?
Southern
Enhydra lutris nereis, the southern sea otter, is the smallest sea otter subspecies.
Asian
Northern
Western

Sea otters are the only carnivores with how many lower incisors?
4
Sea otters are the only carnivores with just four lower incisors.
2
6
8

What is a sea otter’s den called?
Holt
An otter’s den is called a holt or couch.
Couch
An otter’s den is called a holt or couch.
Bevy
Lounge

When was sea otter hunting banned?
1911
Sea otters were hunted to near extinction (1,000 to 2,000 individuals worldwide) at until the turn of the 20th century when the United States, Russia, Japan, and Great Britain reached an agreement in 1911 called the International Fur Seal Treaty, banning the hunting of fur-bearing sea mammals. In 1972, the U.S. Marine Mammal Protection Act offered further protection by banning capture and harassment of sea mammals.
1972
1925
2011

What is the sea otter’s greatest threat?
Oil Spills
Sea otters are vulnerable to large-scale population declines, with oil spills being the greatest anthropogenic threat. The Exxon Valdez oil spill of 1989 had a dramatic effect on the Alaskan sea otter population, killing approximately 5,000 individuals.
Hunting
Climate Change
Invasive Species

What is the sea otter’s lifespan in the wild?
Under Forearms
Sea otters have patches of loose skin under the forearms that they use to help store tools, such as rocks, so they can free up their paws while eating. They also use these loose folds of skin to collect and transport invertebrates during diving.
Under Chin
Between Hind Feet
Entwined in Belly Fur

How long is a young sea otter dependent on its mother?
6-8 Months
The pup typically remains dependent on the mother for about 6 to 8 months after birth.
6-8 Weeks
1 Year
6-8 Days

How long can a sea otter remain submerged?
6 Minutes
Foraging dives usually last 50 to 90 seconds, but otters can remain submerged for nearly 6 minutes.
3 Minutes
30 Minutes
16 Minutes

What is the maximum fine for harming a sea otter?
$25,000
In September 2006, Governor Arnold Schwarzenegger passed a law raising the maximum fine for harming a sea otter to $25,000, and required that all cat litter sold in California display a warning label that advises not to dump cat feces down storm drains or in toilets.
$2,500
$250
$250,000

Sea otters have retractable claws.
True
The sea otter’s hind legs are long and the paws are broad, flat and webbed. The forelimbs are short and have retractable claws, which help with grooming and eating. Sea otters use their small, agile forepaws to capture the prey and rub, roll, twist, and pull the prey apart.
False

Twins occur in how many sea otter births?
2%
Twins occur in 2% of sea otter births.
12%
22%
42%

When do sea otters rest on land?
Stormy Weather
Sea otters spend the majority of their time in the ocean, but rest on land when the population density is high or during stormy weather.
High Population Density
Sea otters spend the majority of their time in the ocean, but rest on land when the population density is high or during stormy weather.
Sleeping
Eating

What advantage does delayed implantation offer the sea otter?
Birth During Favorable Conditions
Sea otters are one of several species of mammals that undergo delayed implantation in which the embryo does not implant during the immediate period following fertilization, but remains in a state of suspended growth allowing for birth to occur under favorable conditions.
Multiple Births per Year
Caudal Fetus Orientation
Larger Genetic Diversity

Which sex of sea otters steals food from the other?
Male
Because males steal food from females if they get a chance, females tend to avoid males except when mating and forage in separate areas.
Female

What limits the sea otter’s northern range?
Sea Ice
Sea ice limits the sea otter’s northern range to below 57 degrees North latitude.
Temperature
Killer Whales
Giant Kelp

How much did you know about the sea otter? Share your results in the comments!

Learn More About the Sea Otter

Sea Otter

Sea Otter

Sea otters are endangered due to large-scale population declines and hunting, but oil spills are their greatest anthropogenic threat.

Sea otters are vulnerable to large-scale population declines, with oil spills being the greatest anthropogenic threat. The Exxon Valdez oil spill of 1989 had a dramatic effect on the Alaskan sea otter population, killing approximately 5,000 individuals.

According to the Otter Foundation, the California sea otter population declined from July 2008 to July 2011. Estimates suggest a California population of approximately 2,700 individuals.

The sea otter was placed under the Endangered Species Act (ESA) in 1973 and is now listed on CITES Appendix I and II. In Canada, sea otters are protected under the Species at Risk Act. As of 2020, the sea otter is considered Endangered by the International Union for Conservation of Nature and Natural Resources (IUCN) Red List of Threatened Species.


Image |©️ Christels, Some Rights ReservedPixabay
Sources | (Allegra & Gunderson 2012; Cohn, 1998; Cray, 2006; Doroff & Burdin, 2011; Jessup, et al., 2004; Nowak, 1999)br>

 

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Sea Otter

Sea Otter

Sea otters are the only carnivores with just 4 lower incisors.

Sea otters are carnivorous. They will eat nearly any fish or marine invertebrate they can find in their kelp forest foraging grounds. Their diet consists of marine invertebrate herbivores and filter feeders such as sea urchins (Strongylocentrotus purpuratus and Strongylocentrotus franciscanus), sea stars (Pisaster ochraceus), limpets (Diodora aspera), coast mussels (Mytilus edulis), chitons (Katharina tunicata), and purple-hinged rock scallops (Crassadoma gigantea). Otters also eat crabs, octopus, squid, and fish.

Sea otters compete with commercial fisheries by feeding on shellfish, sea urchins, and crabs.

Sea otters are the only carnivores with just four lower incisors.


Image |©️ Canopic, Some Rights Reserved(CC BY-NC-ND 2.0)
Sources | (Allegra & Gunderson 2012; Cohn, 1998; Estes, 1980; Estes, Underwood, & Karmann, 1986; Limbaugh, 1961; Nowak, 1999; Paine, 1993)br>

 

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Sea Otter

Sea Otter

Sea otters hunt on the sea floor using their sensitive whiskers to locate prey and their small, agile forepaws to capture the prey and pull it apart.

Sea otter hunting occurs on the sea floor.

Sea otters have circular, furry faces with short noses, rounded eyes and ears, and long whiskers that assist in foraging for food. Sea otters use their sensitive whiskers to locate small creatures in the dense kelp beds and crevices.

The sea otter’s hind legs are long and the paws are broad, flat and webbed. The forelimbs are short and have retractable claws, which help with grooming and eating. Sea otters use their small, agile forepaws to capture the prey and rub, roll, twist, and pull the prey apart.


Image |©️ Sab_k, Some Rights ReservedPixabay
Sources | (Allegra & Gunderson 2012; Cohn, 1998; Estes, 1980; Estes, Underwood, & Karmann, 1986; Fisher, 1939; Limbaugh, 1961; Nowak, 1999; Paine, 1993)br>

 

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Sea Otter

Sea Otter

Great white sharks are one of the primary predators of sea otters, but the otters are also eaten by coyotes, bald eagles, and killer whales.

Great white sharks (Carcharodon carcharias) are one of the primary predators of sea otters. Otters are occasionally eaten by coyotes (Canis lantrans) after taking refuge on the sand during stormy weather. Young pups left alone on the surface while their mothers feed beneath the surface are preyed upon by bald eagles (Haliaeetus leucocephalus).

It was once thought that killer whales (Orcinus orca) were responsible for declines in the sea otter population in Alaska, but evidence is inconclusive.


Image |©️ Tony’s Takes, Some Rights Reserved(CC BY-NC-ND 2.0)
Sources | (Allegra & Gunderson 2012; Estes, 1980; Estes, Tinker, & Doak, 1998; Kuker & Barrett-Lennard, 2010; Limbaugh, 1961; McShane, Estes, Riedman, & Staedler, 1995;)br>

 

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Sea Otter

Sea Otter

The Asian sea otter is the largest subspecies, followed by the northern sea otter, leaving the southern sea otter as the smallest.

The Asian sea otter is the largest subspecies and has a slightly wider skull and shorter nasal bones than both other subspecies.

Northern sea otters are slightly larger than Californian otters. Adult male northern sea otters weigh 27 to 39 kilograms, while females weigh 16 to 27 kilograms. Adult male southern sea otters average 29 kilograms in mass, while females average 20 kilograms. Northern sea otters possess longer mandibles (lower jaws) while southern sea otters have longer rostrums and smaller teeth.


Image |©️ B W, Some Rights Reserved(CC BY-NC-ND 2.0)
Sources | (Allegra & Gunderson 2012; Campbell & Santana, 2017; Cronin, Bodkin, Ballachey, Estes, & Patton, 1996; Doroff & Burdin, 2015; Estes, 1980; Lockwood, 2006; Nowak, 1999; Paine, 1993; The Wikimedia Foundation, 2020b; Wilson, Bogan, Brownwell, Burdin, & Maminov, 1991)br>

 

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Sea Otter

Sea Otter

Three subspecies of the sea otter are recognized with distinct geographical distributions and facial structures.

Three regional subspecies of the sea otter have been confirmed and are recognized with distinct geographical distributions.

Enhydra lutris lutris, the Asian sea otter, is the nominate species and ranges from the Kuril Islands north of Japan to Russia’s Commander Islands and the Kamchatka Peninsula in the western Pacific Ocean. It was first described by Linnaeus in 1758. In the eastern Pacific Ocean, Enhydra lutris kenyoni, the northern sea otter, is found throughout the Aleutian Islands and southern Alaska and was described by Wilson in 1991. It’s been reintroduced to various locations from south of Prince William Sound, Alaska along the Pacific coast of Canada and into Oregon state in the continental USA. Enhydra lutris nereis, the southern sea otter, is native to central and southern California and was described by Merriam in 1904.

The Asian sea otter is the largest subspecies and has a slightly wider skull and shorter nasal bones than both other subspecies. Northern sea otters are slightly larger than Californian otters. Adult male northern sea otters weigh 27 to 39 kilograms, while females weigh 16 to 27 kilograms. Adult male southern sea otters average 29 kilograms in mass, while females average 20 kilograms. Northern sea otters possess longer mandibles (lower jaws) while southern sea otters have longer rostrums and smaller teeth.


Image |©️ Andrew Reding, Some Rights Reserved(CC BY-NC-ND 2.0)
Sources | (Allegra & Gunderson 2012; Campbell & Santana, 2017; Cronin, Bodkin, Ballachey, Estes, & Patton, 1996; Doroff & Burdin, 2015; Estes, 1980; Lockwood, 2006; Nowak, 1999; Paine, 1993; The Wikimedia Foundation, 2020b; Wilson, Bogan, Brownwell, Burdin, & Maminov, 1991)br>

 

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Sea Otter

Sea Otter

Sea otters are one of the few mammals that exhibit tool use, using rocks to break open prey and storing the rocks in the loose skin under their forearms.

Sea otters are one of few mammals that exhibit tool use.

Sea otters have patches of loose skin under the forearms that they use to help store tools, such as rocks, so they can free up their paws while eating. They also use these loose folds of skin to collect and transport invertebrates during diving.

Sea otters break open prey items with hard shells or exoskeletons with a rock. Some otters hold the rock on their chest and drive the prey into the rocks. Others leave the prey on their chests and hit the prey with the rocks. The same rock is kept for many dives.

Otters often wash their prey by holding it against their body and turning in the water.


Image |©️ Andrew Reding, Some Rights Reserved(CC BY-NC-ND 2.0)
Sources | (Allegra & Gunderson 2012; Cohn, 1998; Estes, 1980; Estes, Underwood, & Karmann, 1986; Fisher, 1939; Limbaugh, 1961; Nowak, 1999; Paine, 1993)br>

 

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Sea Otter

Sea Otter

When resting or sleeping, sea otters float on their backs and wrap themselves in kelp to keep from drifting.

Sea otters spend the majority of their time in the ocean, but rest on land when the population density is high or during stormy weather.

When resting or sleeping, sea otters float on their backs and wrap themselves in kelp to keep from drifting. Their hind limbs stick out of the water and their forelimbs are either folded on their chest or used to cover their eyes.

While a mother sea otter is foraging, she also wraps her pup in kelp at the water surface to keep it from drifting away.


Image |©️ Andrew Reding, Some Rights Reserved((CC BY-NC-ND 2.0)
Sources | (Allegra & Gunderson 2012; Cohn, 1998; Estes, 1980; Estes, Underwood, & Karmann, 1986; Fisher, 1939; Limbaugh, 1961; Lockwood, 2006; Nowak, 1999; Paine, 1993)br>

 

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Sea Otter

Sea Otter

Sea otters are a keystone species and are vital to the overall health and diversity of the kelp forest ecosystem by controlling herbivorous invertebrates.

Sea otters are vital to the overall health and diversity of the kelp forest ecosystem. Their presence is believed to be important in the evolution of kelp forest ecosystems.

Sea otters are considered a keystone species and play a major role in the community by controlling herbivorous invertebrates. Sea otters prey on sea urchins, thereby preventing sea urchins from overgrazing the kelp forest. This allows the kelp forest to thrive and contributes to an increase in marine diversity.

The variety in the sea otter diet reduces competition between benthic grazers and supports greater diversity in those species.


Image |©️ Anchor Lee, Some Rights ReservedUnsplash
Sources | (Allegra & Gunderson 2012; Cohn, 1998; Estes, 1980; Estes & Duggins, 1995; Estes & Palmisano, 1974; Estes, Smith, & Palmisano, 1978; Jessup, et al., 2004)br>

 

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Sea Otter

Sea Otter

Sea otters are social creatures and congregate in groups known as rafts or pods, though females tend to avoid males except when mating because males steal their food.

Sea otters are social creatures and congregate in groups known as bevies, families, lodges, rafts, romps, or pods, when resting. Romp is descriptive of their playful nature, while raft is descriptive of their water-floating habits. Sea otters commonly feed in small groups.

Because males steal food from females if they get a chance, females tend to avoid males except when mating and forage in separate areas.

Although many males actively defend their territories with splashing and vocal displays, fighting is rare.


Image |©️ Andrew Reding, Some Rights Reserved(CC BY-NC-ND 2.0)
Sources | (Allegra & Gunderson 2012; Cohn, 1998; Estes, 1980; Estes, Underwood, & Karmann, 1986; Fisher, 1939; Limbaugh, 1961; McShane, Estes, Riedman, & Staedler, 1995; Nowak, 1999; Paine, 1993; Riedman, Estes, Staedler, Giles, & Carlson, 1994; The Wikimedia Foundation, 2020a)br>

 

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Sea Otter

Sea Otter (Enhydra lutris)

Throughout the month of May 2020, FaunaFocus will feature the endangered sea otter!

Sea otters are diurnal mammals that inhabit the Pacific Ocean off the coasts of North America and Asia. These carnivorous creatures are one of the few mammals to exhibit tool use and use rocks to break open prey. As social creatures, sea otters spend much of their time floating on their backs in small groups.

 

GET INVOLVED

Create art inspired by the sea otter and share it in the FaunaFocus Discord Server or on social media with #faunafocus. Learn about more ways to get involved with FaunaFocus!
 

EVENTS
Event Date Time (CDT)
Free-For-All: Deadline May 29 12:00 pm
Free-For-All: Livestream May 30 7:00 pm

 


Image | ©️ Tony’s Takes, Some Rights Reserved(CC BY-NC-ND 2.0)

Sea Otter

Sea Otter

Sea otters typically remain in the same area for years and males have larger home ranges than females.

Sea otters are long-lived and typically remain in the same area for years. An otter’s den is called a holt or couch.

Male sea otters have larger home ranges than females. The home range of a male may overlap with that of several females. Many males actively defend their territories. Disputes are usually settled with splashing and vocal displays, and fighting is rare.

Same-sex territories do not overlap and are defended by their owners.


Image |©️ Christels, Some Rights ReservedPixabay
Sources | (Allegra & Gunderson 2012; Cohn, 1998; Estes, 1980; Estes, Underwood, & Karmann, 1986; Fisher, 1939; Limbaugh, 1961; McShane, Estes, Riedman, & Staedler, 1995; Nowak, 1999; Paine, 1993; Riedman, Estes, Staedler, Giles, & Carlson, 1994; The Wikimedia Foundation, 2020a)

 

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Free-For-All
Judges
Noelle M. Brooks Mister Morgue Robin
Date April 2020 Theme Slender-Snouted Crocodile
Entries 5 Winner Sarah

The month of April 2020 has come to a close and with it, the FaunaFocus Free-For-All featuring the slender-snouted crocodile has concluded. 5 different artists decided to depict this scaly reptile in their own unique styles using both traditional and digital media.

Congratulations to the winner Sarah, who depicted the crocodilian Egyptian god, Sobek, as a slender-snouted crocodile. With a pleasing color scheme and attention to detail, this piece wowed the judges. Sarah’s realistic rendering of the crocodile’s scales echoed the tones of the human-like body and created an impressive looking character.

June 2020’s FaunaFocus has already been selected and will be announced at the end of May 2020’s Free-For-All. OrangeDrawer was last month’s FaunaFocus Free-For-All winner and allowed the FaunaFocus moderation team to select May’s FaunaFocus. For May 2020, FaunaFocus will feature the endangered sea otter!


FaunaFocus Calendar | Free-For-All | Free-For-All Archives

Slender-Snouted Crocodile

Slender-snouted crocodiles do not secrete chitinases, so any chitinous or keratinous substances, such as hair or mollusk shells, accumulate in the gut and are ejected through the mouth.

Slender-snouted crocodilians do not secrete chitinases, so any chitinous or keratinous substances such as hair or mollusk shells accumulate in the gut and are most likely ejected through the mouth (which has been observed many times in captive individuals).


Image |©️ Markus Schroeder, Some Rights Reserved (CC BY-NC-ND 2.0)
Sources | (Grigg & Gans, 1993; Lavinder & Pennington 2012; Pauwels, et al., 2003; Platt, et al., 2002)

 

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Slender-Snouted Crocodile

Do you think you know the slender-snouted-crocodile? Test your knowledge of slender-snouted crocodile FaunaFacts with this trivia quiz!

Click on an answer choice to receive instant feedback. Red answers are incorrect, but allow you to continue guessing. Green answers are correct and will provide additional explanatory information. Sometimes more than one answer is correct!

Learn More About the Slender-Snouted Crocodile | Play on Quizizz


What is the slender-snouted crocodile’s diet?
Carnivorous
Slender-snouted crocodiles have a carnivorous, predatory diet.
Herbivorous
Omnivorous
Unknown

Slender-snouted crocodiles can swim at birth.
True
Young slender-snouted crocodiles are fully capable of feeding and swimming from the moment that they hatch.
False

What are the rocks held in the stomachs of slender-snouted crocodiles?
Gastroliths
The stomachs of slender-snouted crocodiles and other crocodilian species often contain gastroliths (rocks held in the digestive tract) of various sizes.
Ossicones
Plumicorns
Shalites

Slender-snouted crocodiles are sexually dimorphic.
True, males are larger.
As in all crocodilian species, sexual dimorphism is present in slender-snouted crocodiles with males being larger than females of the same age class.
False
True, females are larger.

What factor of the slender-snouted crocodile’s nest determines the sex of its hatchlings?
Temperature
All crocodilian species, including the slender-snouted crocodile, lay eggs, with the temperature of nesting conditions determining the sex of hatchlings.
Humidity
Hemisphere
Depth

What is the slender-snouted crocodile’s parental investment?
Both, Maternal & Paternal
Newborn slender-snouted crocodiles are defended and cared for by both parents for some time after hatching.
Maternal
Paternal
None

What body part is short relative to the size of the slender-snouted crocodile’s body?
Limbs
Due to their limbs being short relative to the size of the rest of their body, slender-snouted crocodiles move somewhat awkwardly outside of the water.
Snout
Tail
Teeth

What habitats do slender-snouted crocodiles inhabit?
Forest
Slender-snouted crocodiles inhabit forest, savanna, inland wetlands, marine neritic, and marine coastal/supratidal habitats.
Savanna
Slender-snouted crocodiles inhabit forest, savanna, inland wetlands, marine neritic, and marine coastal/supratidal habitats.
Wetlands
Slender-snouted crocodiles inhabit forest, savanna, inland wetlands, marine neritic, and marine coastal/supratidal habitats.
Marine Neritic
Slender-snouted crocodiles inhabit forest, savanna, inland wetlands, marine neritic, and marine coastal/supratidal habitats.

For what are slender-snouted crocodiles hunted?
Skin
Slender-snouted crocodiles provide two major economic benefits, skin and meat.
Meat
Slender-snouted crocodiles provide two major economic benefits, skin and meat.
Teeth
Claws

What is the slender-snouted crocodile’s mating system?
Polygyny
Slender-snouted crocodiles are polygynous. Males will only live near females during mating seasons, passing from female to female within their territory. Dominant males will breed with all of the females within their territory.
Polygynandry
Monogamy
Polyandry

To what continent are slender-snouted crocodiles endemic?
Africa
Slender-snouted crocodiles are native to central Africa, from as far west as Senegal, to Tanzania in the east, as far north as Chad, Mali, and Mauritania, and as far south as Zambia and Angola. The Saint Paul, Mafa, and Saint John Rivers are all Liberian rivers in which this species occurs. Slender-snouted crocodiles have also been reported in areas of Cameroon and Gabon.
Asia
South America
Australia

What is a group of slender-snouted crocodiles called?
Bask
A group of slender-snouted crocodiles is called a bask or congregation.
Congregation
A group of slender-snouted crocodiles is called a bask or congregation.
Colony
Siege

What are the slender-snouted crocodile’s primary senses when underwater?
Touch
Touch receptors and the ears are likely to be the primary sense organs used while crocodilians are underwater.
Hearing
Touch receptors and the ears are likely to be the primary sense organs used while crocodilians are underwater.
Vision
Smell

Slender-snouted crocodiles produce the ___ average number of eggs per clutch among species in the genus.
Lowest
Among species in the genus Crocodylus, slender-snouted crocodiles produce the lowest average number of eggs per clutch.
Highest

How do slender-snouted crocodiles show dominance?
Raising Body Out of Water
Vision plays an integral role in crocodilian communication, with males showing their dominance to intruders using different rituals, including raising their bodies out of the water to try to appear larger to intimidate their intruders.
Tail Whipping
Combat Dance
Gaping Mouth

As with all crocodilian species, adult slender-snouted crocodiles are capable of severely injuring or killing humans.
True
As with all crocodilian species, adult slender-snouted crocodiles are capable of severely injuring or killing humans.
False

What are young slender-snouted crocodiles called?
Crocklet
Young slender-snouted crocodiles are called crocklets.
Calf
Chick
Codling

How does the slender-snouted crocodile differ from other crocodiles?
Slender Snout
As the common name suggests, the slender-snouted crocodile can be distinguished from other crocodile species by its extremely long, slender snout which lacks any bony ridges. It can also be distinguished by its dark, olive-colored back and bright yellow-colored ventral surface, which also shows several dark patches.
Darker Back
As the common name suggests, the slender-snouted crocodile can be distinguished from other crocodile species by its extremely long, slender snout which lacks any bony ridges. It can also be distinguished by its dark, olive-colored back and bright yellow-colored ventral surface, which also shows several dark patches.
Dark Patches
As the common name suggests, the slender-snouted crocodile can be distinguished from other crocodile species by its extremely long, slender snout which lacks any bony ridges. It can also be distinguished by its dark, olive-colored back and bright yellow-colored ventral surface, which also shows several dark patches.
Darker Ventral Surface

What type of predator is the slender-snouted crocodile?
Ambush
As with all other crocodilians, the head of the slender-snouted crocodile is well-suited for its ambush predatory lifestyle.
Ballistic
Pursuit
Forager

Which sex of slender-snouted crocodile begins the courtship ritual?
Female
Females approach males in the water and begin the courtship ritual.
Male

When is the slender-snouted crocodile breeding season?
Early Rainy Season
Reproduction generally takes place at the start of the rainy season, oogenesis in females and spermatogenesis in males beginning in January and February.
Late Rainy Season
Late Dry Season
Early Dry Season

What triggers mother slender-snouted crocodiles to uncover their nests?
Baby Squeaking
Soon after the slender-snouted crocodile offspring hatch, they begin to make squeaking noises, triggering the female to uncover the nest.
Baby Scent
Lower Humidity
Colder Temperature

Slender-snouted crocodiles are cannibalistic.
True
Recent hatchlings face many of the same predators, as well as potential cannibalism by larger conspecifics.
False

What is the slender-snouted crocodile’s status on the IUCN Red List of Threatened Species?
Critically Endangered
The slender-snouted crocodile is listed as “Critically Endangered”.
Endangered
Vulnerable
Near Threatened

What is the slender-snouted crocodile’s scientific name?
Mecistops cataphractus
The slender-snouted crocodile’s scientific name is Mecistops cataphractus.
Mecistops eptorhynchus
Tomistoma schlegelii
Crocodylus niloticus

Which sex of the slender-snouted crocodile constructs the nest?
Female
Slender-snouted crocodile nests are made by the female. They are typically 50 to 80 centimeters high, 130 to 220 centimeters long, and 120 to 200 centimeters wide.
Male
Both, Male & Female

Slender-snouted crocodile’s have a semi-transparent third eyelid.
True
When hunting underwater, a semi-transparent third eyelid closes over the eye, likely limiting vision to light/dark differentiation.
False

What is the slender-snouted crocodile’s population trend?
Decreasing
Based on the current estimated subpopulation declines and local extinctions throughout the Sahel, Lake Mweru, and Lake Tanganyika it is anticipated that slender-snouted crocodile subpopulations will become extinct.
Increasing
Unknown
Stable

What threatens the slender-snouted crocodile?
Exploitation
The slender-snouted crocodile is threatened by explotation, habitat alteration, human encroachment, invasive species, and population reductions.
Habitat Alteration
The slender-snouted crocodile is threatened by explotation, habitat alteration, human encroachment, invasive species, and population reductions.
Invasive Species
The slender-snouted crocodile is threatened by explotation, habitat alteration, human encroachment, invasive species, and population reductions.
Human Encroachment
The slender-snouted crocodile is threatened by explotation, habitat alteration, human encroachment, invasive species, and population reductions.

What do slender-snouted crocodiles eat?
Fish
When young, the slender-snouted crocodile’s diet consists mainly of aquatic species, particularly fish and small crustaceans. At larger sizes they feed on terrestrial mammals that drink from the rivers and lakes where the crocodiles live, such as water chevrotains (Hyemoschus aquaticus).
Ungulates
When young, the slender-snouted crocodile’s diet consists mainly of aquatic species, particularly fish and small crustaceans. At larger sizes they feed on terrestrial mammals that drink from the rivers and lakes where the crocodiles live, such as water chevrotains (Hyemoschus aquaticus).
Crustaceans
When young, the slender-snouted crocodile’s diet consists mainly of aquatic species, particularly fish and small crustaceans. At larger sizes they feed on terrestrial mammals that drink from the rivers and lakes where the crocodiles live, such as water chevrotains (Hyemoschus aquaticus).
Seagrass

How long are slender-snouted crocodiles at birth?
28-35 cm. / 11-14 in.
Newly emerged hatchlings measure 28 to 35 centimeters long. Young slender-snouted crocodilian hatchlings resemble mature adults, except smaller.
18-25 cm. / 7-10 in.
38-45 cm. / 15-18 in.
8-15 cm. / 3-6 in.

Why do slender-snouted crocodiles eat rocks?
Break Down Food
Although the purpose of the stones in slender-snouted crocodiles’ stomachs has yet to be confirmed, it appears likely that they serve to grind and break down food in the digestive tract, as is the case in other groups, such as herbivorous birds, seals, and sea lions, where they have been found.
Clean Teeth
Absorb Nutrients
Sharpen Teeth

What is the maximum recorded length of a slender-snouted crocodile?
4 m. / 13 ft.
Slender-snouted crocodiles are small to medium-sized crocodilians, with a maximum recorded length of approximately 4 meters. Individuals over 3-3.5 meters are now rare, however.
2 m. / 6.5 ft.
3 m. / 10 ft.
5 m. / 16 ft.

What is the ideal temperature of a slender-snouted crocodile nest?
27-34º C / 81-93º F
During incubation, mother slender-snouted crocodiles try to keep egg temperatures between 27.4º Celsius and 34º Celsius by keeping them in the nest.
22-27º C / 71-83º F
33-39º C / 91-103º F
16-23º C / 61-73º F

How long is slender-snouted crocodile incubation?
90-100 Days
Slender-snouted crocodile nests house incubating eggs for 90 to 100 days.
119-130 Days
19-20 Days
9-10 Days

Which sex of slender-snouted crocodile guards the nest?
Female
After a nest has been made and a clutch has been laid, slender-snouted crocodilian mothers guard their nests regularly throughout the incubation period.
Male
Both, Male & Female
None

What waters does the slender-snouted crocodile inhabit?
Freshwater
They are most frequently found in freshwater environments and occasionally in brackish waters of coastal lagoons.
Brackish Water
They are most frequently found in freshwater environments and occasionally in brackish waters of coastal lagoons.
Saltwater

How do slender-snouted crocodiles traverse?
Belly Crawl
Mainly, slender-snouted crocodiles will belly crawl through mud or on the banks of a river. They may also high walk by standing straight up on all four legs to move around on rougher, rockier terrain. While swimming, slender-snouted crocodiles move in a very graceful, serpentine motion through the water.
Quadrapedal Walking
Mainly, slender-snouted crocodiles will belly crawl through mud or on the banks of a river. They may also high walk by standing straight up on all four legs to move around on rougher, rockier terrain. While swimming, slender-snouted crocodiles move in a very graceful, serpentine motion through the water.
Swimming
Mainly, slender-snouted crocodiles will belly crawl through mud or on the banks of a river. They may also high walk by standing straight up on all four legs to move around on rougher, rockier terrain. While swimming, slender-snouted crocodiles move in a very graceful, serpentine motion through the water.
Bipedal Walking

Which part of the slender-snouted crocodile lacks bony ridges?
Snout
Protective scales cover the slender-snouted crocodile’s skin, some of which are reinforced by bony plates to provide extra support. The snout lacks bony ridges, however.
Back
Tail
Stomach

Slender-snouted crocodiles are territorial.
True
Male slender-snouted crocodilians are very territorial and will not tolerate other males or intruders in their territories.
False

What is the slender-snouted crocodile’s alternate name?
West African Slender-Snouted Crocodile
The slender-snouted crocodile is also known as the West-African slender-snouted crocodile. The Central African slender-snouted crocodile is a different species.
Central African Slender-Snouted Crocodile
North African Slender-Snouted Crocodile
South African Slender-Snouted Crocodile

How long have captive slender-snouted crocodiles lived?
38 Years
No reliable information is available regarding the average lifespan of wild slender-snouted crocodiles, but captive individuals have been documented to live for at least 38 years.
18 Years
28 Years
48 Years

Slender-snouted crocodiles can see in color.
True
It’s assumed that crocodilians can see in color because their eyes have both rods and cones.
False

Slender-snouted crocodiles produce the ___ average egg size among species in the genus.
Largest
Among species in the genus Crocodylus, slender-snouted crocodiles exhibit the largest average egg size.
Smallest

Slender-snouted crocodiles perform visual displays to attract potential mates.
True
During mating season, crocodilian species perform visual displays to attract potential mates.
False

What are the sexes of slender-snouted crocodile called?
Bull & Cow
Male slender-snouted crocodiles are called bulls, while females are called sows.
Jack & Jenny
Buck & Doe
Boar & Sow

Slender-snouted crocodiles secrete chitinases.
False
Slender-snouted crocodilians do not secrete chitinases, so any chitinous or keratinous substances such as hair or mollusk shells accumulate in the gut and are most likely ejected through the mouth (which has been observed many times in captive individuals).
True

Efforts to protect which species are also protecting the slender-snouted crocodile?
Chimpanzee
While the Sene-Gambia subpopulation is currently well protected, any loss of will to continually protect the chimpanzee (Pan troglodytes) colonies will result in near instantaneous extinction of this subpopulation.
Ring-Tailed Lemur
Western Gorilla
African Wild Dog

What features suit the slender-snouted crocodile’s predatory lifestyle?
Forward-Facing Eyes
As with all other crocodilians, the head of the slender-snouted crocodile is well-suited for its ambush predatory lifestyle, with nostrils that sit high on the tip of the snout and eyes that face forward at the top of its head. This allows it to lie in wait at the edge of the water and stalk its prey while the rest of the body is almost completely submerged underwater, sit-and-wait style. Their eyes also contain a tapetum lucidum, a layer of guanine-rich retinal cells that amplify incoming light and greatly improve night vision.
Facial Features on Top of Head
As with all other crocodilians, the head of the slender-snouted crocodile is well-suited for its ambush predatory lifestyle, with nostrils that sit high on the tip of the snout and eyes that face forward at the top of its head. This allows it to lie in wait at the edge of the water and stalk its prey while the rest of the body is almost completely submerged underwater, sit-and-wait style. Their eyes also contain a tapetum lucidum, a layer of guanine-rich retinal cells that amplify incoming light and greatly improve night vision.
Camouflage
As with all other crocodilians, the head of the slender-snouted crocodile is well-suited for its ambush predatory lifestyle, with nostrils that sit high on the tip of the snout and eyes that face forward at the top of its head. This allows it to lie in wait at the edge of the water and stalk its prey while the rest of the body is almost completely submerged underwater, sit-and-wait style. Their eyes also contain a tapetum lucidum, a layer of guanine-rich retinal cells that amplify incoming light and greatly improve night vision.
Night Vision
As with all other crocodilians, the head of the slender-snouted crocodile is well-suited for its ambush predatory lifestyle, with nostrils that sit high on the tip of the snout and eyes that face forward at the top of its head. This allows it to lie in wait at the edge of the water and stalk its prey while the rest of the body is almost completely submerged underwater, sit-and-wait style. Their eyes also contain a tapetum lucidum, a layer of guanine-rich retinal cells that amplify incoming light and greatly improve night vision.

What activities do slender-snouted crocodiles partake in courting?
Chasing
During this courtship, crocodilians perform several activities involving swimming around each other and bodily contact. The female may even briefly swim away to encourage the male to chase her before continuing to circle.
Circling
During this courtship, crocodilians perform several activities involving swimming around each other and bodily contact. The female may even briefly swim away to encourage the male to chase her before continuing to circle.
Biting
Tail Whipping

When do slender-snouted crocodiles lay eggs?
April
Around April, egg-laying occurs.
January
October
July

What preys on young slender-snouted crocodiles?
Otters
Predation on crocodilians occurs mainly at the egg or hatchling stage. Various animals feed on the eggs of slender-snouted crocodiles, including spotted-necked otters (Hydrictis maculicollis), leopards (Panthera pardus), and various bird and rodent species.
Leopards
Predation on crocodilians occurs mainly at the egg or hatchling stage. Various animals feed on the eggs of slender-snouted crocodiles, including spotted-necked otters (Hydrictis maculicollis), leopards (Panthera pardus), and various bird and rodent species.
Birds
Predation on crocodilians occurs mainly at the egg or hatchling stage. Various animals feed on the eggs of slender-snouted crocodiles, including spotted-necked otters (Hydrictis maculicollis), leopards (Panthera pardus), and various bird and rodent species.
Rodents
Predation on crocodilians occurs mainly at the egg or hatchling stage. Various animals feed on the eggs of slender-snouted crocodiles, including spotted-necked otters (Hydrictis maculicollis), leopards (Panthera pardus), and various bird and rodent species.

What percentage have slender-snouted crocodile populations declined?
50-80%
The slender-snouted crocodile is inferred to have undergone a past population reduction of between 50-80% based on direct observation, loss of range and suitable habitat, direct exploitation and the impacts of introduced species. The reduction is closer to 50–60% for Central Africa and 70–90% for West Africa.
10-40%
20-50%
60-90%

What provides the slender-snouted crocodile’s forward propulsion?
Tail
Power for forward propulsion is provided by the tail, with the limbs providing very little, if any, aid in swimming.
Fore Feet
Hind Feet
Bony Ridges

In what genus was the slender-snouted crocodile originally categorized?
Crocodylus
The slender-snouted crocodile’s genus reclassifcation has not yet been adopted by the International Code for Zoological Nomenclature (ICZN), and most authors continue to use the genus name Crocodylus when referring to this species.
Mecistops
Tomistoma
Osteolaemus

With what do slender-snouted crocodiles construct nests?
Hind Legs
Slender-snouted crocodile nests are made primarily of dead vegetation and mud by the hind legs. They are typically 50 to 80 centimeters high, 130 to 220 centimeters long, and 120 to 200 centimeters wide.
Fore Legs
Snout
Tail

How does the slender-snouted crocodile’s hearing compare to other reptiles?
More Sensitive
Hearing is very well-developed in crocodilians and is more sensitive than in other reptiles.
Less Sensitive

Why do slender-snouted crocodiles share nests?
Deter Predators
Female crocodilians of various species, included slender-snouted crocodiles, have shown evidence that the nests of some species may be shared between multiple females. It’s believed that these species share nests to allow better deterrence of predators.
Cooperative Breeding
Limited Resources
Increase Temperature

It is anticipated that slender-snouted crocodile subpopulations will become extinct within how many generations into the future?
1
Based on the current estimated subpopulation declines and local extinctions throughout the Sahel, Lake Mweru, and Lake Tanganyika it is anticipated that slender-snouted crocodile subpopulations will become extinct within one generation into the future.
2
3
5

Slender-snouted crocodiles continuously grow new teeth.
True
They continuously grow new teeth to replace any that are lost through fighting or feeding.
False

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