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.

Characteristics

  • 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.

Behavior

  • 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

Hunting

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.

Diet

  • 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.

Reproduction

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.

Threats

  • 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

Resources:

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.

Habitat

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.

Lifespan

 10-11 years

Reproduction

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.

Threats

  • 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:

Anphibiaweb.org – Anaxyrus boreas 
ASPCA – The Trouble with Toads: Getting to the Bottom of this Toxic Threat
CaliforniaHerps.com – 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

Savethefrogs.com

The University of British Columbia – Roseanna Gamlen-Greene Western Toad Ecology
USDA Forest Service – Anaxyrus boreas – fire effects information 
Wikdipedia.org – https://en.wikipedia.org/wiki/Western_toad

Mountain Lion – Fragmented Power Pouncer

History

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

Characteristics

  • 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.

Behavior

  • 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 pray 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.

Diet

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.

Reproduction

  • 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 | mountainlion.org

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.

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click image to download coloring sheet

 

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

 

Resources:

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 
Wikipedia.org – Cougar

Predator Proofing for Livestock & Pets:

Preditor Proof Pens

Wildlife Rescue | Sonoma County | Puma Proof Pen

Tail Flashing Cache Faker – Western Gray Squirrel

Habitat

The Western Gray Squirrel is a tree (arboreal) rodent and is the largest of its kind in the Sierra Nevada Mountains weighing between one-half to two pounds. Tree squirrels like dense cover in which to travel across branches, build several kinds of nests, and seek safety. They live at nearly every elevation in Nevada County. Favorite trees are the black oak.

Characteristics

Like crows and ravens, tree squirrels are keen people watchers. If you live in their territory, chances are they know a lot more about you than you do about them. Active during the day, squirrels understand human activity patterns and they can recognize the people who feed them and the people who thwart them.

In spring they undergo a full body molt and in fall a neck to rump molt.  

Behavior

As with the North American Beaver, Porcupine, and other rodents, a squirrel’s teeth grow continuously. They must gnaw and chew to keep them from getting too long.

When a Wester Gray Squirrel finds a nut, it will roll it for approximately twenty seconds. Biologists think the animal is evaluating the quality of the nut -if it should be eaten immediately or cached away for winter. 

Twenty-second nut roll. Behavior thought to be nut quality evaluation. Eat now or cache for later.

The cache fake-out happens when a squirrel pretends to bury a nut – with other squirrels watching – then moves to another place to actually burry it. Another impressive aspect of squirrel behavior is their ability to memorize the location of their caches. 

(Eastern Gray Squirrel - identified by brown fur around eyes - shown in video)


Many tail uses;

  • blanket
  • blood coolant
  • climbing counterbalance
  • raincoat
  • communication

If a squirrel holds its tail in an S shape, it’s feeling threatened. It waves it to look larger.

Another special skill is leaping up trees, all four paws raise at the same time, but it happens so quickly it’s difficult to see. When going down a tree, their back feet rotate so claws act as anchors. 

Leaping. Photo Credit: Dan Johnson

When traveling long distances, a squirrel’s preferred travel mode is from branch to branch, high off the ground. When foraging for food, or hurrying between caches, they will scamper on the ground, but at the first sign of danger, back to tree safety they go! 

Native Western Gray Squirrels need a continuous stretch of mature oak trees for survival. 

‘Sleep rough’ is thought to be a method of temperature control. This is when a squirrel lays on its belly, spread out as much as possible. Often they’ll do this on branches but it’s also been observed on the ground, on the picnic tables, or anywhere that is squirrel appealing.

Sleeping rough is thought to be a behavior that helps regulate body temperature.

Defense Behavior

Western Gray Squirrels work cooperatively like many prey animals to sound alarm warnings. 

 

(Fox Squirrel shown in video)

In the winter, squirrels don’t hibernate but they do slow down. This is when nut caches are consumed.

Diet

  • acorns
  • pine nuts
  • new leaf buds
  • fruit
  • bird eggs
  • seeds
  • small birts
  • fungi
  • bark
  • sap
  • insects

Raiding bird feeders is summer fast-food. As winter approaches, they devote more time to scatter-hoarding.

*Forgotten caches help trees grow in new locations. 

Western Gray Squirrels compete for the same food sources as the acorn woodpecker, ground squirrels, and other introduced squirrel species (S carolinensis and S. niger).

Life Span

7-8 years

Reproduction

Breeding happens in late spring starting at about a year old. A female signals readiness with enlarged, pink vulva and a male with a scrotum that turns from pink to black. The act of mating is vigorous and taxing.

Nesting mothers use their own molted hair to line the nest (drey). She’ll also use shredded bark, moss, and lichens.

Gestation is about 43 days. Younger females will have smaller litters compared to more mature breeding females who average between 3 – 5 hairless kits. Babies nurse for about two months but stay in the nest for about six months total. Tails don’t fill out until babies are out of the nest.

The second type of nest build by Wester Gray Squirrels is a sleeping platform, it is not as enclosed as the birthing nest and is for temporary use.  

Predators

  • bobcats
  • coyote
  • foxes
  • owls
  • hawks
  • house cats

Habitat Threats

  • urbanization habitat loss
  • roadkill
  • wildfires
  • fire suppression management
  • overgrazing
  • scotch broom invasive species
  • mite diseases
  • competition with introduced squirrel species and wild turkeys

If you liked this post, you may also like Einstein Corvidae – Crows and Ravens

 

click image to see more Life on the Creek art

 

Resources:

Agility test

Bay Nature – Are Fox Squirrels Replacing Gray Squirrels in California?

iNaturalist – Western Gray Squirrel

Phys.org – Squirrels have a long memory for problem solving

U.S. Fish & Wildlife Service – Conboy Lake (WA) – Western Gray Squirrel

Wikipedia – Western Gray Squirrel

 

 

 

 

Three-eyed Push-Up Tyrant with Break-Away Body Parts

The western fence lizard is also known as a blue-belly because of the brightly colored scales under its throat and at the outer edges of the underbelly. It is a fossorial (burrowing) poikilotherm (an animal that regulates body temperature by sun basking or dirt burrowing).

In females and youngsters, the blue markings are faint or not there at all.

Characteristics

This lizard measures 2 inches to 3.5 from nose to snout. Eight inches total, including the tail.

Because of its pointed, overlapping scales, it’s a member of the spiny lizard genus –  Sceloporus.

Colors range from sandy, black, brown to green. Some may have back stripes. Under the arms may be yellowish. Western fence lizards have the ability to change colors. Biologists think this adaptation relates to maintaining body temperature rather than for camouflage.

Third Eye

The third or parietal eye is located at the top of the lizard’s head. It’s covered by a translucent scale. Its purpose is to sense light throughout the year, signal the onset of reproduction and it helps control body temperature.

Behavior

The length of winter hibernation is dependent on climate conditions.

Defenses

  •  Fast, biting, and defecating on predators
  • Dropping tail – caudal autotomy or self-amputation (Scientists measure from snout to vent because of the break-away tail)

 

Push-Ups

Functions of the Push-ups;

  • courtship – fitness demonstration – the more brilliant colors, the healthier the male (low parasite load)
  • territorial defense display – in mating season, males defend an approximate 25-foot radius from a high perch
  • may also relate to food availability within the territory
  • a dominant male guarding at the highest point in the territory is known as a tyrant 

Diet

A blue-belly’s favorite food is insects. It will eat beetles, grasshoppers, ants, wasps, aphids, mosquitoes, ticks, scorpions, centipedes, and spiders. It will also eat other western fence lizards! 

Shedding

As they grow, lizards shed skin in pieces. Sometimes, it becomes a snack. Successful shedding depends on diet, health status, and environmental conditions.

Life Span

5-7 years

Predators

Birds, snakes, alligator lizards, and cats.

Male Identification 

Like birds, male western lizards are more brightly colored and showy than females. Where the tail meets the body, males have two large scales near the vent, a single opening used for waste elimination and reproduction.

While copulating, the male’s blue color is at its most brilliant.

Reproduction

Male identification at 2:17


Western fence lizards begin breeding after one year.

Mating Season – March – June

Egg size is largest with the first clutch. The number of clutches laid in a season depends on temperature and elevation. At lower elevations, females will lay between 1-4 clutches. At higher elevations, they’ll lay between 1-3 clutches. Each clutch can contain between 3-17 eggs.

Eggs and Hatching

Eggs incubate for approximately 2 months. Once hatched, babies fend for themselves.

 

Disease Benefits to Humans

Western fence lizards have a protein in their blood that filters out the spirochete bacterium in Deer Ticks that cause Lyme disease. After a tick feeds on a lizard it will not spread Lyme disease to its next, larger, host during its life cycle.

 

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

 

If you liked this post, you may also like Deer Tick, A Questing Blood Sucker

 

Resources:

Bay Nature – How You Can Tell Male from Female Lizards? 

In Tech Open – Reptilian Skin and Its Special Histological Structures

John Muir Laws – Lizards, Ticks, and Lyme oh my! (audio)

MonkeySee – How to Care for Pet Lizards (video)

Natural History Museum of Los Angeles – ‘Tis the Season fo Baby Lizards

Purdue University – Shedding Reptiles (PDF)

Reptilian Third Eye

San Francisco State University – Department of Geography –   The Biogeography of  Sceloporus occidentalis

Sci Show – How Do Animals Re-Grow Limbs (And Why Can’t We?)

UC Berkeley News – Tick population plummets in absence of lizard hosts

University of California Agriculture & Natural Resources – Pests in Gardens and Landscapes – Lizards
Lizards cause no measurable damage to plants in gardens and may be beneficial by eating pest insects and should be left alone.”

BioWeb – Western Fence Lizard

WIRED – Lizards Use Third Eye to Steer by the Sun

Wikipedia – Western Fence Lizard