River Otters – Holt Hiding, Wiggly Weasel Cousin

River Otters are apex predators like mountain lions, coyotes, sharks, and killer whales. In healthy ecosystems, they maintain balance.

Habitat & History

Before North America’s European colonization and the fur trade (that continued until 1961), River Otters inhabited every fresh waterway on the continent.

For a species greatly impacted by human behavior, they have become a beacon of hope for nature’s resilience. With clean water and air laws, resulting in healthier environments, River Otters are repopulating on their own.



Unlike their sea-faring relatives, River Otters function both on land and in water.

They are crepuscular – active in the early morning and twilight hours – and busy year-round. While River Otters don’t migrate with seasons, they will travel up to 25 miles to search for food sources. Areas, where otters have taken up residence, are those that have all the right ingredients for the good life; plenty of cover vegetation, rock piles, logs, clean water, and an adequate supply of food.

Adults weigh between 10-30 pounds. They can remain underwater for up to 4 minutes, swim up to 7 miles per hour, and dive to 60-foot depths.

They live in social groups, most consist of a mother and her offspring. Males also live together in ‘bachelor pods.’

River Otters hunt and travel together. They share the same den, latrines and groom each other.

Special Adaptations

  • Nictitating membranea third eyelid (like Bald Eagles) covers the eyes when swimming underwater
  • Ears and nostrils close underwater
  • Thick, water-repellant layer of fur
  • Powerful tail for swimming
  • Clawed, flipper feet – able to climb trees

Play Behavior

Known for play, River Otter behavior is similar to teenage cats. Games of chase, wrestling, and pretend fighting are common as young learn hunting skills.



Highly communicative, otter families (aka bevy, lodge, or romp) use scent and sound to convey meaning. Scent can be in the form of urine, feces, anal jelly, and musk from glands located in their back feet. Low-frequency chuckling, bird-like chirps, snorts, purring grunts, and shrill whistles are some of the sounds they make when alarmed, looking for family members, playing, or frightened.

Life Span

In the wild, the North American River Otter life span is between 8 to 12 years. In captivity, they’ve been known to live up to 25 years.

Holt & Reproduction

River Otters are opportunistic home finders like Western Bluebirds. A holt or couch is also known as a den. It must have enough underground interior room for family raising, be near clean water and food sources, above flood level, and have multiple entrances and exitssome above and below water level, often near Beaver dams, in embankments, or under logs.

Mature otters can mate any time between December and April. Unlike their European counterparts, North American River Otters have the ability to delay implantation for up to eight months.

Gestation lasts about two months.

In early spring, pregnant mothers find and prepare holts. This is where they will give birth from one to six kits who will remain with her for up to a year. At birth, otter pups are toothless, fully furred and they weigh about the same as a medium-sized apple. At around a month-and-a-half old, kits open their eyes and begin playing.

At around two-months-old, thick water fur fills in and the mothers begin teaching pups to swim. To do this, she holds them by the scruff, drags them into the water, and dives with them.


Adult River Otters eat between 2 to 3 food per day. Being busy balls of energy with thick coats to maintain, they eat often and prefer protein in the form of fish. Other items river otters consume include;

  • Salamanders
  • Frogs
  • Freshwater clams & mussels
  • Snails
  • Turtles
  • Crayfish
  • Small birds
  • Squirrel 
  • Mice

Elimination Notes

Similar to raccoons, River Otters use latrines (common defecation areas). Latrines are away from living spaces and, in addition to a site for expelling body waste, they serve a function as a location to leave powerful territorial scent markings.


Field biologists search for otter latrines. Scat and anal jelly—a black mucus coating that protects the digestive tract from sharp objects—yield DNA that can be used to track otter movement as well as clues to what the animals are eating.


In the water river otters are generally safe from predation. On land, they are vulnerable to;

Diseases to which River Otters are Susceptible

  • Hepatitis
  • Jaundice
  • Pneumonia
  • Rabies
  • Canine distemper
  • Feline panleukopenia
  • Also susceptible to diseases carried by parasites such as ticks, lice, and fleas

Humans & Otters

River otters were nearly wiped out in the early fur trade era on the North American continent. In recent years, habitat destruction and fragmentation, with dams, roads, and expanding housing developments, as well as water pollution have impacted River Otter populations.

When humans create monocultures such as fish hatcheries and ponds, River Otters are only too happy to take advantage of them. So-much-so that they become pests. Sadly, nuisance otters pay the price for their ‘misbehavior’ with relocation and death.

An unexpected but encouraging result of the US EPA Clean Water Act (1972) shows evidence of River Otters repopulating fresh waterways on their own. Visit the River Ecology Project Map to watch an ever-growing list of otter sightings throughout California (Zoom in on Nevada County). Or visit the project on iNaturalist.


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A Conclusion

For the writer and editor, this post signifies a conclusion to the multi-year watershed study project. River otters, like Western Bluebirds represent hope. Hope that, collectively, humanity learns to reprioritize its values. No longer can we thoughtlessly sprawl and use up resources. Space for nature and wild animals as well as keeping a clean house (air and water quality) are needed to maintain balance in every ecosystem….and they are all connected.

If anything, 2020 has held before us a harsh microbial mirror that we must spend time examing. The halt in business-as-usual created an opportunity for a significant pivot. I hope we can. And I hope we do!

While I plan to write a few more FDC articles here-and-there, my focus has turned to complete the editing process on a 30-minute Deer Creek centered film – Aerial Views and History of the Deer Creek Watershed.

Thank you for joining along on the Deer Creek journey! I hope you take away information to love and share about your watershed.

Lisa Redfern



Bay Nature Magazine – After Decades Away, River Otters Make a Triumphant Return to the Bay Area (2016)
Bay Nature Magazine – What Do River Otters Do When the River Runs Dry in a Drought?
International Otter Survival Fund – How to build an Otter Holt
National Wildlife Federation – Conservation: An Otterly Amazing Comeback (2011)
North American Nature – How Do Otters Communicate?
Otter Spotter Sigthings Map 2013-2016
Phys.org – What otter droppings can tell us
River Otter Ecology Project
Smithsonian’s National Zoo & Conservation Biology Institute – North American river otter
UC Santa Cruz – River Otters are Back (2016)
UC Santa Cruz – Science Notes PODCASTRiver Otters return to San Francisco Bay Area 
United States Environmental Protection Agency – Clean Water Act (1972)
USFWS – You Otter Know: The Difference Between River and Sea Otters
Wikipedia – North American River Otter

Rescue Otter Oregon Zoo


River Otters in Yellowstone with Coyote Predators (warning: animal violence)


Happy Cavity Nesting Families – Western Bluebird

Bird of Good Cheer and a Hopeful Spring

Throughout history, and within many cultures, bluebirds symbolize happiness, protection, and hope. People may have first taken notice of the birds because of their unusual coloring, or for their behavior; swooping through meadows and open spaces, cheerful song, or large family units raising young each spring.

When the bluebirds start building nests this spring (2021), it will signal a time when COVID quarantines and isolation may begin lifting. For those with creative inclinations, this cheer inspiring avian may, once again, be used to celebrate hope and authentic community freedom in song, writing, painting, filling in blocks of color on a coloring sheet, or building and distributing nest boxes.

Photo Credit: Julio Mulero

Secondary Housing Shortage

Bluebirds lack beak and skull adaptations to bore their own nesting cavities; therefore, they rely on second-hand holes of a certain circumference.

Like many animals highlighted on Following Deer Creek, human-caused environmental alterations – tree management practices and invasive species – have reduced their numbers.

Providing Bluebird nesting boxes (see Bluebird Nest Box Construction below) and replacing exotic plants with California native plants are two ways that individuals can contribute toward repairing California’s diverse natural ecosystems.

“Bluebird conservation is a shining example of a totally grassroots effort that has been tremendously successful. It illustrates the power of individuals and groups to make a difference.” – Elizabeth Zimmerman Smith 2020, Woodstock, CT at Sialas.org


Nevada County Western Bluebirds are year-round residents.

During spring and summer, bluebirds mostly feed on insects. Their hunting grounds are open grasslands where they perch on branches or fence posts to watch for bugs. When they spot prey, they’ll swoop in for the catch. In addition to insect hunting spaces, bluebirds also need reliable sources of fresh water.

Photo Credit: Becky Matsubara

In the winter, they feed on berries.


Females and juveniles have muted feather colors compared to mature males. Both males and females have straight beaks and rusty-colored chest feathers. Mature males have bright blue heads, wings, and tails.


Female left, male right | Photo Credit: Becky Matsubara

Social Behavior


Life Span

3-5 years

Life cycle

Reproduction & Family Chick Raising

Spring begins with nest building. Bluebirds choose existing cavities in which to nest.

Feb/March/April – males and females pair bond.

Females lay one egg a day for a clutch between 4 – 6 days.

After a fourteen-day incubation, with the male bringing her food and standing guard, all eggs hatch on the same day.

After hatching, both parents feed chicks for approximately two weeks.

Photo Credit: Shirley Binn

Once the young have fledged and begin traveling from the nest box to hearby branches, the female leaves to begin building a second nest while the male finishes caring for the first brood.

Bluebirds remain in family groups. First brood siblings may help raise the second brood. Inexperienced parents with failed nests may participate in helping raise their parents’ subsequent hatchlings.


Spring / Summer

  • grasshoppers
  • caterpillars
  • beetles
  • ants
  • butterflies

Fall / Winter

  • small fruit & berries
  • mistletoe
  • juniper berries
  • elderberry



domestic & wild cats




Nesting Box Chick Predators

  • bees
  • ants
  • earwigs
  • wasps

Undernourished chicks are also susceptible to parasitic infections.

Cavity Competitors

House Sparrows and Starlings are aggressive cavity-nesting competitors that were imported into New York between 1853 and 1890. The first to deal with inchworms and the second to introduce Shakespeare’s play birds into Central Park.

Other Birds that Compete for Cavity Nest Sites

  • Nuthatch
  • Chickadee
  • Swallow
  • House Wren


Detrimental Human Effects on Bluebird Populations

  • Introduction of competitive invasive species – House Sparrow & Starling
  • Tree & Forest Management practices
  • Herbicide & pesticide use
  • Wood fence post replacement with angle iron posts
  • Development of open spaces

The Bluebird Man – One Idaho Man’s Retiremet Conservation Legacy

Bluebird Restoration Project – Near Victoria, British Columbia

Bluebird Nesting Box Construction

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or view more Life on the Creek Art


click image to download FREE coloring sheet

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Audubon – How to Build a Bluebird Nest Box
Audubon – Western Bluebird
BBC – The birds of Shakspeare cause US trouble
Bear Yuba Land Trust – Bird Banding with Allison Nelson
California Bluebird Recovery Program
Cornell Lab of Ornithology – Educators Guide to Next Boxes
Cornell Lab of Ornithology – Nest Watch – national nest monitoring program
Cornell Lab of Ornithology – Western Bluebird
Ebird – Western Bluebird Identification & Call recording
Ebird – Western Bluebird Range Map
The Hatching Cat – 1853: The English House Sparrows Who Took Up House and Hotel in Manhattan
iNaturalist – About Western Bluebird
iNaturalist – Nevada County Western Bluebird Observations
North American Bluebird Society
North American Bluebird Society – Getting Started with Bluebirds PDF
San Diego Tribune – Bluebirds of Happiness keep local resident enchanted
Sailas.org – Bluebird Nest Box Style Pros & Cons
Wild Birds Unlimited (Grass Valley, CA)
Wikipedia – Bluebird of Happiness
Wikipedia – Western Bluebird

More Bluebird Videos:

Male Song

Eastern Bluebird – Brain Study – Male/Female Song Area

Making of Bluebirdman

Bluebirds in Popular Culture:

From Red Dead Redemption 2 to the Wizard of Oz, Sesame Street’s Big Bird, Niel Young, and Native American folklore the bluebird makes consistent appearances in American popular culture. It has also shown up in  as well as in ancient Chinese, Japanese, Native American and European folklore, the bluebird has symbolized hope, happiness, protection and change.
The symbol of a bluebird as the harbinger of happiness is found in many cultures and may date back thousands of years.


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
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  • 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

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Creek Art

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

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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. 


California Department of Fish and Wildlife Twenty-five Year Dear Population Estimates

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)

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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



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