Hummingbird – High-Speed Nectar Sipper

The hummingbird is one of the world’s smallest, oldest, and most adapted living bird species. Part of the Trochilidae family, hummingbirds are in the Apodiforme subfamily, which means ‘unfooted’. Because their wings move them around so well, they don’t need feet for much more than perching.

Between North and South America, over 800 plant species have evolved to rely on hummingbirds for reproduction! Basically, most trumpet flowers are shaped to fit hummingbird beaks.


European hummingbird fossils have been found that are between 40-50 million years old.

Species You’ll See in  Nevada County

Calliope, Black-Chinned, Rufous, Anna’s

Anna’s hummingbirds can be full-time Nevada County residents.


Hummingbirds currently live in both North and South America, but many of them are mobile, spending spring in the north and winter where it’s warmer, between Alaska and Mexico.

Distinctive Characteristics

  • Smallest living vertebrate
  • Fastest wing beats of any bird
  • Fastest metabolism of almost all animals some species hearts beat 1,000/minute
  • Needs to eat frequently during daylight hours

Special Adaptations

  • Small feet used for perching not walking
  • Long hover times (compared to other birds)
  • 49 mph in flight diving speeds
  • Consumes more than its body weight of nectar each day
  • Frequent urinator – Urinates more than its body weight every day (to keep water weight down)
  • Excellent visual memory – enlarged hippocampus to remember visited flowers
  • Specialized nectar sipping tongues – channels along both sides open and close, acting like an ultra-efficient sponge
  • Sleep time is torpor time  – 105 degree body temperature drops to around 50 degrees, heartbeat slows to 36 beats/minute (it beats over 1,000 beats per minute when active)
  • Torpor can also be entered if food becomes scarce
  • Bright feather coloring is the result of pigmentation and prism-like cells in a layer on top of the color
Click here to order this image.


  • Nectar – in the wild, hummingbirds visit flowers for food, extracting nectar, which is 55% sucrose, 24% glucose, and 21% fructose 
  • Insects
  • Aphids
  • Gnats
  • Fruit Flies
  • Mosquitoes
  • Spiders


With such a high-speed metabolism, these tiny birds generate a lot of heat! Instead of sweating, hummingbirds evaporate moisture a and heat on featherless body structures such as around their eyes, feet, and under the wings. Their exhales also expel heat and moisture. 

Hummingbirds are territorial. They’ll defend flower patches and feeders aggressively. Some studies show aggressive behavior increasing with an increased sugar content of feeder water.


Beyond vocalizations, and their unusual ability to remember songs,  hummingbirds also make vibration sounds with their feathers. Some males, such as the Anna’s,  make whistle /chirping noises with outermost tail feathers during courtship displays.

The Male Tail Trill;

  • Announces the sex and presence of a male bird
  • Provides audible aggressive defense of a feeding territory
  • Is an intrusion tactic
  • Enhances threat communication
  • Helps with mate attraction and courtship


The Rufous hummingbird is the most common species you’ll see in Nevada County. Of all the varieties, it makes the longest migration – 3,900 miles – between Mexico and Alaska. Because it spends time in harsher weather conditions, it can survive below-freezing temperatures.

Click on image to visit live migration map (during migrations)

Life Span

While chicks have very high mortality rates, the birds that reach adulthood live between 3-5 years. However, some banded birds were observed living for up to twelve years.


For males, reproduction is about flashy color displays and elaborate dances.

Females are nest builders and egg sitters. A mother will lay two eggs at a time, incubating them between two weeks to 23 days.

In order to sit long enough to keep eggs warm, females go into torpor. Once hatched, newborns hide, hunkering down deep in the nest only reaching out when they feel the breeze from their mother’s wings.

Fledglings remain in the nest for just over two weeks.

Mother’s feed young a nutrient-dense mash of insects, pollen, and nectar.


How Human Activity Affects Hummingbirds

  • Pesticides in the garden and on crops poison the birds directly or indirectly through the food supply
  • Habitat loss – reduces the native plant food supply
  • Feeders reduce plant pollination activities
  • Feeders near windows increase bird into glass collisions
  • Some sweeteners contain iron or bacteria that adversely affect hummingbird health

 Sweeteners NOT to Use in Feeders

  • Brown sugar
  • Agave
  • Molasses
  • Stevia 
  • Splenda
  • Equal
  • Any diabetic sweetener
  • Raw sugar
  • Honey
  • Any packaged hummingbird mix that contains red die, artificial flavors, dietary supplements, or vitamins (native flowers provide everything they need!)

If You Do Feed Wild Hummingbirds

Use this mixture – 1 cup of white sugar to 4 cups water

Hummingbird with pollen on beak. Photo credit: Wikimedia commons Kpts44

Rewild Your Garden

The BEST way to attract and support hummingbirds is with native plants.

“Flowers should be chosen for their ability to produce nectar, to grow well in your particular region, and to be in bloom when the hummingbirds need them.”  – Redbud Chapter California Native Plant Society

Click here for a Redbud Chapter CNPS hummingbird attracting plant list PDF

Click on image to purchase or view more Life on the
Creek Art

If you live outside Nevada County California, click here for a list of North American Native Plant Societies.

If you liked this post, you may also like Lichen: Exploring Microecosystems in Your Backyard

Click image to download a FREE coloring sheet

Resource Videos:


BBC News – Oldest Hummingbird Fossils Found (Germany) 

Hummingbird Central – Migration maps

iNaturalist – Hummingbirds

Independent – Found in France, A 30 million-year-old hummingbird fossil

Nature – Behind the Scenes of Hummingbirds

Popular Mechanics – Hummingbirds Can See Colors We Humans Can’t

Redbud Chapter California Native Plant Society – Native Plants for Landscaping (Pollinators)

Science Alert – Hummingbirds Can See Colors We Can’t Even Imagine, Experiment Reveals

Scientific American – Fossils Reveal Hummingbirds Once Flew Farther Afield

Wikipedia – Hummingbirds

Columbia Black-tailed Deer – Crepuscular Cud Chewer 

The word ‘deer’ is an irregular noun. It is used for both single and multiple animals. Deer are also crepuscular, active during twilight hours.

Of the six subspecies of mule deer living in California, Nevada County is home to two; the California mule deer (west side of Sierra Nevadas to the southern coast) and the Columbia black-tailed deer (Northern California through the Pacific Northwest). Since black-tailed deer are the species roaming through my yard, they are the main subject of this article.

History & Range

The Columbia black-tailed deer is also known by the names; Pacific buck, Columbian deer, coast black-tailed buck, and black-tailed deer. It is a subspecies of Mule deer and will cross-breed with the California mule deer and Rocky Mountain mule deer where habitats overlap.

In 1846, an Oregon Trail traveler noted black-tailed deer as far west as Wyoming. Today their range is smaller. It includes northern California, Oregon, Washington, some parts of coastal and interior BC as well as the Alaskan panhandle.

With the 1934 Taylor Grazing Act, the organization that eventually became known as the Bureau of Land Management was tasked with managing public forage lands for cattle and wildlife. It became one of the numerous organizations cooperating across state and county lines to track and manage these wild animals. ( US Forest Service, California Department of Fish and Wildlife and U.S. Department of Agriculture.)


  • large ears, relaxed
  • short, stubby tail
  • loose tail position
  • winter coat color – silver gray
  • cap / patch of fur at top of head
  • thicker stripe of dark fir on tail than Mule deer


Except for breeding season (November – December), does and bucks live in separate groups. 

Female groups of related individuals are led by a dominant (alpha) animal, usually the eldest mother. She chooses foraging and birthing grounds. The alpha female is usually the first to mate during mating season and she generally chooses to stay close to her mother’s territory, leaving it only if forced.


Males leave their mothers between a year-and-a-half and eighteen months old to seek bachelor groups.

New antlers (bone protrusions) are grown each spring and shed every winter. 

Antlers are grown out with a ‘velvet’ covering, a living structure with blood vessels. Once it dries and antlers harden, bucks rub them against trees to remove the velvet. A buck’s age is reflected in the number of forks. Antlers are used for sparring and determining social position as well as for mate competition. 



Communication methods include vocalizations, scent, and pheromones. Glands between the toes, and near the knees (hock) create trail marking and individual recognition signals while glands outside the lower legs produce alarm scents. 

Large, independently moving, ears enable sensitive hearing. 


In California, at higher elevations, some herds of black-tailed deer migrate. Locations of forage food and snow levels determine their movements.

In Nevada County, below Nevada City, seasonal herd movements do not cover great distances.

Life Span

The black-tailed deer life span is approximately 7 years (in the wild), reaching sexual maturity between 1-2 years.


Males are polygynous, they’ll mate with multiple females.

Female gestation lasts between six to seven months, with fawns born May – June.

For the first week after birth, fawns have no scent. This allows the mother to leave her babies to replenish her body weight and produce adequate amounts of milk for her young.

Caution: Mothers with fawns view humans as predators.


Like cattle, sheep, giraffe, goats, and antelope, deer are cud-chewing grazers. With teeth and mouthparts specialized for breaking down cellulose as well as a digestive compartment housing bacteria necessary to turn plant material into protein, volatile fatty acids as well as vitamins B and K, deer spend the early morning and dusk hours grazing and afternoon and evening hours, bedded down, regurgitating, and giving food a second chew. 

Spring and winter diet includes;

  • California Buckeye
  • Douglas-fir
  • Fern
  • Lichen
  • Huckleberry
  • Poison oak
  • Grasses
  • Cedar
  • Bark & buds

Late spring and fall diet includes;

  • Grasses
  • Fruit (blackberry & apple)
  • Fireweed
  • Pearly everlasting
  • Forbs
  • Rosehips
  • Salmonberry
  • Salal
  • Maple trees
  • Acorns

Rumination – Chewing Cud

Grazer gut bacteria often match soil microbes. Eating and defecating perpetuate healthy regeneration cycles for both plants and animals.

Grazing to Heal the Earth – Grasses & Ruminants | 3:14 Chewing Cud


  • Mountain lion
  • Coyote
  • Eagle
  • Bear
  • Humans

Deer Hunting Industry & Income Generation

In California, Deer hunting permit sales generate around $450 million dollars annually, attracting between 165 – 200K hunters. 


Issues Affecting Deer Habitat & Populations

  • Habitat loss & fragmentation
  • Herbicide use on private and public lands
  • Timber & reforestation practices – biomass, hardwood removal, clear-cutting & thinning
  • Livestock grazing
  • Prescribed fire & fire suppression & wildfires
  • Reservoirs
  • Ski areas, golf courses & agricultural land uses
  • Poaching
  • Changing weather patterns including severe winters and drought
  • Highways and roads (1.5 million deer and vehicle collisions/year – Insurance Institute for Highway Safety)

Click image to purchase or see more Life on the Creek art

click image to download FREE coloring sheet



If you liked this post, you may also like Mountain Lion – Fragmented Power Pouncer.



Bay Nature – Are Deer Twins Common?
California Department of Fish and Game – Assessment of Mule and Black-tailed Deer Habitats and Populations in California – 1998 [PDF] California Department of Fish and Wildlife –
Mule Deer
California Department of Fish and Wildlife – Deer Management Documentation
California Department of Fish and Wildlife – Deer Population Estimates
California Department of Fish and Wildlife – Private Lands Management
iNaturalist – Columbian Black-tailed Deer
Journal of Wildlife Disease – Hair-Loss Syndrome in Black-tailed Deer of the Pacific Northwest
Mule Deer Foundation
Mississippi State University | Deer Ecology & Management Lab – Antler Growth Cycle
National Park Service – Pacific Coast Science and Learning Center – Black-tailed Deer Researchers, References & Links
Sierra Club – 
Largest Mule Deer Migration Ever Recorded
Western Hunter – Black-tailed deer of California
Wikipedia – Ruminants

Mule Deer Migrations

Nevada & Texas Deer Herd Management


Bald Eagle – Symbolic Feet Fighting Food Thief

How the Bald Eagle Became the Symbol of the United States 

In 1776, members of the Continental Congress passed a resolution saying the new nation needed a formal seal for official documents.

Benjamin Franklin, John Adams, and Thomas Jefferson comprised the first committee who would work on it.

Secretary of the Continental Congress, Charles Thompson designed the United States Great Seal in 1782. It symbolizes strength, unity, and independence.

Bald Eagle Habitat

According to iNaturalist, there have been four Bald Eagle sightings in the Deer Creek watershed so far this year – mostly concentrated around Lake Wildwood. I was excited to see one flying down the canyon near Newtown this spring, but with no camera in hand, I could only squeal with glee!

This raptor’s habitat includes all of North America, some parts of northern Mexico, and Canada. They prefer large lakes and rivers with plenty of fish and tall trees. Some populations are year-round residents along both coasts, along the Mississippi River, in the Rockey Mountains, and in Alaska. Other bird populations are migratory.


  • large predatory and scavenging birds
  • adult plumage – white head and tail feathers – appears between 4 to 5 years of age
  • females are larger than males
  • feet are adapted to snatching fish out of water
  • beaks are adapted to ripping flesh
  • food storage in crop – after a gorge, birds can go one to two weeks without eating
  • weights between 8 to 14 pounds
  • has a wingspan between 6.5 to 8 feet
  • fierce ‘expression’ is caused by a bony forehead ridge that protects eyes from branches and prey struggles

Eagles have multiple eyelids. The top one blinks up. The inner one – nictitating membrane – sweeps across. Eagle tears protect against saltwater, destroys bacteria, and prevent infections.


  • juvenile birds give way to their elders
  • parents don’t mediate sibling rivalry
  • feet have a ratcheting mechanism that allows them to clamp onto prey


Bald Eagles can travel 40 miles per hour in flight and 100 miles per hour in a dive! They have excellent eyesight, It is said that they have the ability to spot prey up to two miles away.


  • salmon and other fish
  • coots and other small birds
  • rodents
  • they’ll also steal carrion from other animals

Feet Fighting

Bald eagles use their best weapons to ward off attacks and fight for territory – their feet!

Late winter, during the time they’re getting preparing to mate, is when most of the territorial disputes occur. As habitat loss increases, territorial fighting increases in intensity.


Life Span

Twenty-eight years in the wild, 30 years in captivity.


Both males and females participate in sitting on eggs and parenting. A pair, while separating outside mating season, will come together year after year to mate and reproduce.

If one of the pair dies, the survivor will look for a new mate at the beginning of the next mating season.

Beeding season is between January through August.

Platform nests – aeries – are constructed at the tops of trees. They’re about 6’x6′ and can weigh over a ton! Eagle pairs will often return to their nest site.

A clutch consists of two to three eggs. Incubation is approximately one month.

After chicks have hatched, experienced parents ball their feet when entering the nest so as not to injure young with their talons.


  • habitat loss from road and housing developments
  • cars
  • mercury and other heavy metals
  • pesticides (DDT used for mosquito abatement)

Conservation Success Story

Bald eagles were the first animal to be placed on the endangered species list in the late 1960s. At that time, there were only 30 nesting pairs left in northern California. It was discovered that DDT caused thin eggshells. It was banned in 1972.

With conservation and management efforts, eagle populations recovered. The animal was removed from the endangered list in 2007.

Bald Eagles are still protected under the Migratory Bird Treaty Act and the Bald and Golden Eagle Protection Act.



click on image to purchase or see more Life on the Creek art.

click on image to purchase or see more Life on the Creek art.

If you liked this article, you may also like Mountain Lion – Fragmented Power Pouncer


California Department of Fish and Wildlife – Bald Eagles in California
Cornell Lab of Ornithology – Bald Eagle
National Museum of American Diplomacy – Great Seal of the United States
National Wildlife Federation – Bald Eagle
U.S. Fish & Wildlife Service – National Bald Eagle Management Guidelines
USGS – Todd Katzner, Supervisory Research Wildlife Biologist
Wikipedia – Eagle Eye
Wikipedia – Great Seal of the United States



Western Toad – Zot Drought Survivor

Toads don’t cause warts.

If your dog tries to eat one, it might foam-at-the-mouth.


With a wide habitat range, western toads can be found from sea level to 11,000 feet elevation and from Baja, Mexico to Alaska.

Like other amphibians, toad numbers have been declining in recent decades, but new field observations give cause for hope. Evidence appears to show that they can adapt to reproducing outside accustomed seasonal cycles and they’ll take advantage of water to breed in, even if it’s not their ‘home water.’

Characteristics & Behavior

Western toads come in a variety of colors – reddish-brown, yellow, green, gray, or white. 

Rough, blotchy bumps can have red centers.  It usually has a light-colored stripe going down the length of its back and large “cheek” glands.

Photo Credit: Spaltedalder

Once a toad leaves its natal water body in spring, they live on the land where they dig shallow burrows, occupy gopher and ground squirrel holes, beaver dams or find protected spaces under rocks or tree roots near water sources such as bogs, streams, meadows, lakes, and rivers. 

Their body temperatures are largely controlled by sun basking and evaporative cooling. In order to avoid drying conditions, they spend the daylight hours on the forest floor in the soil under rocks, logs, stumps, or other surface objects or in rodent burrows.

In June, when temperatures begin to rise, they remain in their burrows, only coming out at dusk or night time to feed.

Like bats, toads have the ability to go into a state of torpor (partial hibernation) during unfavorable living conditions, such as when it’s very hot, cold, or dry. At high elevations, they can go into full hibernation.  (Their blood contains a sugar that acts like antifreeze, protecting organs in extreme cold.)

After waking from winter sleep, western toads migrate back to the water to mate and lay eggs. 

Photo Credit: Steve Collins Valley Conservation

Toads lay eggs in strings, rather than clumps. Hatchlings tend to stay together through metamorphosis.

Tadpole  Diet

  • Suspended plant materials in the water
  • Bottom detritus
  • Carrion

Tadpole Predators

  • Birds
  • Amphibians
  • Mammals
  • Fish

Adult Diet

  • Ants
  • Bees
  • Beetles
  • Butterflies
  • Crayfish
  • Earthworms
  • Fleas
  • Flies
  • Grasshoppers
  • Moths
  • Snails
  • Sowbugs
  • Spiders
  • Slugs
  • Worms

Quick tongue action to catch prey is called a ‘zot’.

*See video in Resources about special saliva.

Adult Predators

  • Ravens, crows, and other birds
  • Snakes
  • Badgers, foxes, bobcats & other mammals

Defense Mechanisms

Peeing and defecating are defense mechanisms. To deter predators, adult toads secrete a mild milky (alkaloid) neurotoxin from glands located on their neck, back, and shoulders. 

Females deposit a small amount of the toxin on newly laid eggs.


 10-11 years


Western toads become sexually mature and able to reproduce between 4 – 6 years old.

Wildlife biologists think toads use smell to travel between breeding territories. They need shallow, open water and tend to return to the same spot each year. 

Unlike other frog species, male western toads do not have vocal sacs. 

Males will compete for a female. Even without a vocal sac, males make a chirping sound as other males approach. He’ll kick competitors away to defend her.

Between March and July, breeding occurs.  Females lay eggs in long strings, up to 17,000 at a time! It takes about three months to complete the metamorphosis from tadpole to toad.

Water temperature regulates metamorphosis speed.


  • Competition with introduced species (not native animals kept as pets and set free)
  • Fungal infection from chytridiomycosis
  • Absorption of fertilizers in water systems
  • Absorption of mineral pollutants from mine water drainage
  • Worm parasites
  • Habitat destruction
  • Warming water temperatures

Toads & Dogs – Tips to Reduce the Possibility of Poisoning

  • Don’t leave pet water (or food) outside. Toads are attracted to it.
  • If a toad has soaked in your pet water, it could make your pet sick.

Signs of Toad Poisoning

Signs that your dog has tried to eat a toad include;

  • Foaming-at-the-mouth is a sign that your pet may have tried to eat a toad.
  • Pawing at the mouth
  • Excessive drooling
  • Pet might vomit it swallowed a whole toad

If you saw where it happened, it’s a good idea to – carefully – retrace your animal’s steps to verify the cause. (Always be aware that rattlesnakes can also be a possibility!)

 Most U.S. toads are only mildly toxic (highly toxic varieties live in Hawaii, Southern California, Arizona, New Mexico and along the Colorado River). 

Poisoning First Aid  

If your pet is conscious;

  • Rinse mouth with a hose pointing from the back of the mouth out, nose tipped down.
  • If possible, don’t let your animal swallow the flush water.
  • Don’t induce vomiting unless instructed by your vet.
  • Continue rinsing for 5 to 10 minutes

Call your vet.

Five dollars from every sale goes to support non-profit creek stewardship organizations. Click on the image to purchase or see more Life on the Creek art.


Click image to download a free coloring sheet.

If you liked this article, you may also like Sierra Newt – Powerful Water Drive & Deadly Skin or Sierran Tree Frog with Chemical Sensitivities 

Resources: – Anaxyrus boreas 
ASPCA – The Trouble with Toads: Getting to the Bottom of this Toxic Threat – Boreal Toad – Anaxyrus boreas
California Herps – Identifying Toads in California
Canadian – Western Toads 

Core.AC.UK – Late-season Reproduction in Western Toads (Bufo boreas) PDF [2017] 
Global News – Hop to it: Whistler park closed as 40K baby toads hit the road in mass migration
Habitat Conservation Trust Foundation – Toadlet Migration 2018 Update (Canada)
National Geographic Education – Conserve Western Toad (Canada) 
National Park Service – Amphibian Monitoring 
National Park Service – Drought Uncovers New Facts About West Coast Toads 
National Park Service – A Need to Breed: California Toads in the Santa Monica Mountains

The University of British Columbia – Roseanna Gamlen-Greene Western Toad Ecology
USDA Forest Service – Anaxyrus boreas – fire effects information –

Mountain Lion – Fragmented Power Pouncer


Wikipedia commons

Since the late 1850’s, North America’s big cat has been known as the mountain lion. Early Spanish explorers called it ‘gato monte‘ which means cat of the mountain.

Latin America calls it puma (powerful) which comes from the 16th century Peruvian Quechua language.

Because of its wide range, diverse habitats, and the span of human cultural locations, this animal is known by many other names including; cougar, panther, and catamount.

Geographic Habitat

California’s current mountain lion population is between 4,000 – 6,000 animals.

Closely related to the house cat, these big cats are adaptable to a large variety of ecosystems. In the Nevada County portion of the Sierra Nevadas, they like dense underbrush and rocky outcropping habitats.

Highly territorial, males generally claim a 150 square mile area that may vary depending on terrain and prey availability. Females have smaller territories, about half the size, and they stay in the general proximity of their mothers.


“Wherever you see deer in the state, there’s also going to be cougars.”  – Chris Wilmers, Wildlife Ecologist, UC Santa Cruz


  • Mountain lions are the world’s fourth-largest big cat weighing between 150 – 200 lbs. (1. Siberian Tiger | 900 lbs. 2. African Lion | 600 lbs. 3. Jaguar | 300 lbs.)
  • While the mountain lion is an apex predator, it will sometimes give ground to black bears.
  • These cats can swim, although this is not a favorite activity.
  • Hunting mostly during twilight hours and at night, mountain lions are ambush predators. They sit-and-wait, often in concealment, before launching a fast surprise attack.
  • With large paws and powerful hind legs, they’re sprinters that can run between 40 – 50 miles per hour.

Jumping Adaptation

Mountain lions can jump as high as seven queen-sized beds, stacked length-wise, end-to-end. This makes getting into trees easy and is an ambush asset.


  • Traditionally thought to be solitary predators, biologists are currently studying complex family structures.
  • Mountain lions will reciprocally share kills within small communities controlled by dominant males.
  • Mountain lions can kill prey with a single bite to the neck, positioning teeth into the spinal cord between vertebrae.
  • These animals cache their meals. After a kill, they’ll bury the prey and continue visiting the carcass for up to a week. 
  • Males use feces and urine to scent-mark a territory, often scraping leaves and grass into a pile and urinating on it.
  • Young males searching for territory are more likely to fight and cause livestock problems.
  • Mountain lion relocation causes territory disruption, resulting in aggressive behaviors, and conflicts with established males.

Vocalizations are Mostly for Family

Humans may never know about lion neighbors, partly because we don’t recognize their vocalizations.

With other animals, scent marking is the main mode of mountain lion communication.  Within family units, mothers and kittens make a variety of noncat-like sounds.

Mothers make sounds to call for and locate kittens and kittens make distress calls that are answered by their mothers.

Purring may be sibling competition for food.

Caterwauling is used by females mostly in heat.


Mountain lions are obligate carnivores, they must eat meat to survive. Generally, they need to make one large kill (deer) every two weeks.  However, females raising kittens may need to make more frequent kills – every three days.

For an adult, average daily meat consumption is up to 10 lbs.

Food sources include;

  • deer
  • fox
  • skunk
  • rabbits
  • coyote
  • raccoons
  • river Otter
  • bobcat
  • squirrels
  • woodrats
  • rats and other rodents
  • any animal it can catch including livestock and housepets

In a Sonoma County study,

75% of mountain lion diet was deer,

10% livestock, 10% feral and house cats,

and 5% small mammals.


  • Females reach reproduction age between one-and-a-half and three years. Occasionally couples are monogamous, but more often mountain lions mate with multiple partners. During mating, a couple will remain together for about a week. After mating, the males go back to their own territory.
  • Gestation is approximately 3 months.
  • Females will have litters of 1-6 cubs, with an average of about 2. They’ll give birth every 2-3 years.
  • Cubs are born blind.
  • Nursing lasts up to 3 months.
  • Cub survival rate is slightly over kitten one per litter.
  • Kittens have spots for up to about 2 1/2 years.
  • Females raise their kittens alone.
  • Only mothers and offspring spend time together in social groups.
  • Juveniles remain with their mother from 1 1/2 – 2 years, until she’s ready for her next litter.

Photo credit: Eric Kilby

When kittens are nursed, the mother will bring meat to them. As they get older, she takes them to kill sites. Older still, they begin hunting small mammals on their own.

Photo credit: National Parks Service

Causes of Kitten Mortality

  • coyote
  • bear
  • hypothermia
  • wildfires
  • male mountain lions

Habitat Fragmentation A Breeding Problem

Southern California mountain lion studies reveal that male lions must have the ability to safely move between wide swaths of land to access and breed with diverse female populations.

With movement constricted by busy freeways, inbreeding occurs. This genetically weakens populations.

Mountain lion inbreeding tail deformities

Crooked tails are a genetic defect from inbreeding. Article: Genetic Connectivity Threatens a Southern California Puma Population by Ernst, Vickers, Morrison & Boyce

Experts believe if inbreeding continues, the Southern California mountain lions will go extinct within in the next 50 or 60 years.

Mountain lion inbreeding tail deformities

Ten genetic populations of California mountain lions (marked by color) Mountain Lion Foundation |

Life Span

In the wild, the average mountain lion life span is between 8-13 years. In captivity, they’ve been known to live up to 21 years.

Predators & Threats

  • Genetic isolation & inbreeding (habitat fragmentation).
  • Rodenticides (rat and mouse poisons) traveling up through the food chain.  (In a study of 400 mountain lion necropsies, 95% showed some degree of poisoning.)
  • As habitats are encroached upon by humans, mountain lions are coming in contact with and susceptible to feline leukemia, rabies, and other infections.
  • Cars (roadkill).
  • Man and kill permits.

Nevada County Mountain Lion Kill Permits 2011-2019

Nevada County Mountain Lion Depredation Statistics 2011-2019 PDF

What Humans Can Do to Successfully Live in Lion Territory

Since we live in mountain lion territory, we should always assume we have an invisible mountain lion in our backyard and behave accordingly.

  • Don’t use anticoagulant rodenticides.
  • Value and support local and state policies aimed toward mountain lion conservation.
  • Never feed deer or other wild animals and encourage neighbors to do the same. (Wild animals who’ve lost natural fear of humans become a public safety issue, resulting in animal extermination.)
  • Fire safety – removing dense, low-lying vegetation close to your house – is identical for mountain lion safety.
  • Plant deer-resistant plants.
  • Consider outdoor automatic lighting.
  • Reduce driving speeds in wildlife zones, being especially from dawn to dusk.
  • Don’t litter and/or pick up roadside litter.
  • Don’t leave pet food outside.
  • Secure garbage on pick-up days.
  • Don’t let pets roam free.
  • Train guard dogs to watch-over livestock.
  • Build mountain lion resistant (very tall) livestock shelters.
  • Don’t put meat in compost piles.
  • Establish wildlife passage corridors to accommodate animal migration and movement.

Prevent Mountain Lion Encounters

  • Hike in groups.
  • Carry sticks.
  • Don’t bend down to tie shoes.
  • Make lots of noise.
  • Keep children walking in front of adults and within sight.
  • Carry pepper spray.
  • Keep dogs leashed. (A loose, running dog stimulates mountain lion chase behavior. If under pursuit, your pet will bring the chase straight to you!)

Attacks on Humans are Rare

Attacks on humans are very rare! The natural behavior for a mountain lion is to run away.

If a lion doesn’t run immediately;

  • Make sure it isn’t cornered.
  • Be big and loud.
  • Pull your jacket above your head.
  • Don’t crouch down or run.
  • Pick up children and back away.
  • Don’t make intense eye contact.

If it comes to a physical encounter, attempt to;

  • Fight back with rocks and sticks.
  • Stay on your feet.
  • Yell.
  • Protect your neck.

click image to purchase or see more Life on the Creek art

click image to download coloring sheet


If you like this article, you may also like Coyote the Ultimate Adaptor.



Audubon Canyon Ranch – Living with Lions: ACR’s mountain lion research and education project
Bay Area Puma Project
BBC – What it’s like living in California’s mountain lion country [2017] – When a kill permit is issued
California Department of Fish and Wildlife – Commonly Asked Questions about Mountain Lions
California Department of Fish and Wildlife – Mountain Lion
California Department of Fish and Wildlife – Mountain Lion Depredation Statistics Summary
California Department of Fish and Wildlife – Verified Mountain Lion-Human Attack in California [ Two fatalities statewide in 34 years] California Mountain Lions – film & miniseries
CBS Denver – Dog Owner Says Lesson Learned After Encouonger with Moutain Lion [2016]

Conserving Connectivity: Some Lessons from Mountain Lions in Southern California, Morrison, Scott A. and Boyce
Conservation Society of California – Oakland Zoo – Mountain Lion Initiative The Cougar Conundrum: Sharing the World with a Successful Predator by Mark Elbroch | Revelator Article – What’s the Value of a Mountain Lion?
Los Angeles Times – After a nuisance mountain lion was killed, two L.A. city leaders wan to end the practice [2020] Los Angeles Times – Southern California mountain lions get temporary endangered status [2020] Mercury News – Mountain lions get endangered species protections in California
Mountain Lion Foundation
The Nature Conservancy – Animal Tracks 
National Geographic – Exploring the use of five type os puma vocalizations
NPR – The Secret, Social Lives of Mountain Lions | radio program 3:49
Sacramento Bee – California voters banned mountain lion hunting three decades ago, but the killing never stopped [2017] Smithsonian Magazine – California Will Build the Largest Wildlife Crossing in the World [2019] Liberty Canyon Wildlife Crossing PDF

Sonoma West – Living with mountain lions [2019] UC Davis Puma Project – New Study Details the Double Lives of Surburban Pumas [2004] UC Santa Cruz – Power of the pounce – Cougar

Predator Proofing for Livestock & Pets:

Preditor Proof Pens

Wildlife Rescue | Sonoma County | Puma Proof Pen