Category Archives: Wildlife

Ruby-Throated Hummingbird – Facts and Information

ruby-throated hummingbird
Picture from FSW taken by: Robert Burton

Ruby-Throated Hummingbird

General:

The Ruby-Throated Hummingbird (Archilochus colubris,) is one of my favorite backyard sightings, due to its brilliant plumage and spirited behavior. Before you can catch a glance, this acrobatic and energetic bird is usually on its way to the next blossom. This hummingbird has the greatest breeding range of all hummingbirds in North America and occupies much of the eastern United States and Canada during the spring and summer months. By providing the right vegetation and features in your backyard, you may be lucky enough to share your yard with this lovely species.

Description:

The Ruby-Throated Hummingbird is named for the metallic ruby-red throat patch found on the throat of the male hummingbirds. Both sexes have iridescent green plumage on their backs and heads and white undersides. This species of hummingbird has the lowest number of feathers ever found on any bird1. Females may be distinguished from males by their dull gray throats. The tails also differ between sexes, with forked tails present on males and white-tipped square tails on females. Young Ruby-Throated Hummingbirds are similar in appearance to adults, except for fewer red feathers on the throats of adolescent males.

Adult hummingbirds reach 3” to 4” in size, averaging 3.5 grams in weight2. Ruby-Throated Hummingbirds have long bills and tongues, used to drink nectar at an average of 13 licks a second. The tongues are grooved to aid in nectar collection and have fringed edges to help collect insects. This acrobatic flyer has short legs relative to their body length, making walking and hopping difficult and inefficient. Possibly the most unique physical attributes of the Ruby-Throated Hummingbird, besides for the red plumage on the males, are the wings. These tiny and delicate appendages are able to beat an average of 53 times per second, creating this bird’s distinctive “humming” noise. During flight the number of beats per second may be 78 times a second and as high as 200 times a second during a dive (a display used in mating)3. Because of these extreme levels of activity and the tendency to ‘hover’ while eating, Ruby-Throated Hummingbirds have very high metabolic rates. The metabolic rate of these birds at rest is estimated to be 20.6 calories per gram per hour. In addition to their signature hovering, these petite birds are able to fly upside-down and backward.

On average, adult male hummingbirds live to 5 years of age and females live to 9 years in the wild. This species experiences a high mortality rate possibly because of the extreme energy demands of behaviors including breeding displays, migration, and defense of territory, leading to extensive weight loss4.

Ruby-Throated Hummingbirds are a solitary species and typically only interact for breeding or territorial purposes. Male hummingbirds are territorial, using vocalizations to ward off intruders. If an intruder enters another male’s territory, the defending male will make a single note, repeating at higher and higher volumes until the intruder retreats. If the vocal warning is not successful, male hummingbirds are known to chase and physically attract other males (using their beaks and feet.)5 In addition to vocalizations, male and female Ruby-Throated Hummingbirds may communicate with and understand olfactory and visual cues. These birds can see the visible light spectrum as well as the blue-violet range. Developed vision along with their sense of smell helps these hummingbirds identify food sources.

Ruby-Throated Hummingbirds are diurnal, most active during the day. When temperatures drop below optimal levels, hummingbirds enter hypothermic torpor in order to conserve energy. Hypothermic torpor is a state similar to hibernation, allowing a hummingbird to conserve energy through a lowered body temperature and slowed body functions6.
Populations of Ruby-Throated Hummingbirds are wide spread and numerous, with an estimated 7.3 million birds worldwide. This species has never experienced any serious threats and is protected under the Migratory Bird Treaty between the U.S. and Canada. As with all hummingbird species, the Ruby-Throated Hummingbird is part of Appendix II of the Convention on International Trade in Endangered Species7.

Habitat:

Ruby-Throated Hummingbirds fulfill an important role in their habitats, pollinating flowers, shrubs and vines. This symbiotic relationship is so strong that some species of plants have adapted to cater specifically to these small birds. Ruby-Throated Hummingbirds are migratory, inhabiting northern habitats during their summer breeding season and tropical habitats after migrating south for the winter. Preferred habitats include deciduous and pine forests, mixed woodlands, orchards, flowering gardens, parks, overgrown pastures, and citrus groves. Ruby-Throated Hummingbirds select habitats that are close in proximity to water sources such as marshes or streams, to ensure abundant insect supplies8.

Males establish territories that offer food supplies, protection and mating opportunities. Some males have been known to establish a breeding territory distinct from their primary territory when food sources in the primary territory were not sufficient to support mating activities. These separate areas may be as far as two miles apart. Males are defensive of their territories and typically locate their territory at least 50’ away from a territory of another male Ruby-Throated Hummingbird. Territories of Ruby-Throated Hummingbirds may overlap with those of other hummingbird species. In these instances, the male Ruby-Throated Hummingbird will become submissive9.

Within their habitats, Ruby-Throated Hummingbirds are vulnerable to birds-of-prey (including blue jays which feed on nestlings) and, most often, house cats.

Location:

Ruby-Throated Hummingbirds are a migratory species. Between February and May these petite birds fly north to their breeding grounds located across the eastern United States and Canada, east of the 100th meridian. Between July and October Ruby-Throated Hummingbirds embark on a southern migration to their winter grounds that extend from southern Florida south to Panama and the West Indies. This species primarily winters in Central America. Ruby-Throated Hummingbirds are capable of a nonstop, 500-mile flight across the Gulf of Mexico and may go so far as to double their body weight in preparation. The migration of this species coordinates with the blooming schedules of flowers.

Diet:

Ruby-Throated Hummingbirds are omnivorous, feeding on flowers and nectar as well as insects. Adult hummingbirds require an immense amount of calories to support their behaviors and must consume approximately twice their body weight a day. They are most often spotted hovering over flowers as they lick the nectar, consuming approximately half their body weight in sugar a day, spread between five to eight feedings10. Preference has been shown for red flowers, but hummingbirds consume a variety of other flowers and nectar from wildflowers and flowers from shrubs and vines, as well as tree sap (collected from wells excavated by tree-boring bird species.) Insects are collected from sap wells and vegetation and include mosquitoes, small bees, gnats, small flies, aphids, spiders, caterpillars and insect eggs11.

If you are looking to attract hummingbirds to your garden, here is a variety of plantings you may consider:

Flowers:

Begonia, Century Plant, Butterfly Weed, Columbine, Delphinium, Fox Glove, Dahlia, Geranium, Impatients, Lilly, Petunia, Phlox, Snapdragons, Verbena, Sweet William

Vines, Trees, Shrubs:

Honeysuckle, Trumpet Vine, Morning Glory, Butterfly Bush, Rose of Sharon, rosemary, Tulip Poplar

Hanging a hummingbird feeder is also a great way to attract these beautiful birds. Fill your feeder with a concentrated sugar solution (roughly 4 parts sugar to 1 part water.) Boil the mixture until the sugar is fully dissolved. Remember to clean your feeder often, especially during extreme heat. The sugar solution should be changed every few days, especially during high temperatures because heat can cause this solution to spoil.
*Do not use artificial sweetener or honey in your feeder. Honey can ferment and cause hummingbirds to become sick and sweeteners contain no nutritional value13.

Reproduction:

Ruby-Throated Hummingbirds breed while in their northern habitats between March and July, the height of breeding occurring in mid-May. This species inhabits a larger breeding range than all other hummingbird species in North America and is the only species of hummingbird that breeds east of the Mississippi14.

Both male and female Ruby-Throated Hummingbirds take several breeding partners during a given season, although no long-term breeding pairs are established. After copulation pairs separate and females assume all parental duties.

Male Ruby-Throated Hummingbirds return to breeding areas in the spring to establish their territories prior to females’ arrivals. Upon entering a male’s territory, a female will be courted with an acrobatic display: a showy display of red throat plumage and diving displays with males flying in loops above the females. If a female shows interest by perching, the male will proceed by flying in fast horizontal arcs just feet in front of the female. Females may give their final consent by emitting a “mew” and displaying a posture of cocked tail feathers and lowered wings15.

Females are solely responsible for selecting the site for and building a nest. Nests are typically attached to a down-sloping branch by pine resin, below a shelter of leaves, 5’ to 20’ off the ground or a stream. Common trees to find hummingbird nests in are oak, maple, poplar, birch, beech, spruce and pine. Nests are constructed of thistle, ferns, young leaves, moss, dandelion and milkweed down, spider and caterpillar webs, and bud scales and decorated on the exterior with lichen (possibly to provide camouflage.)

Females lay, on average, 1 to 3 small white eggs. After two weeks of incubation, the young birds are born and will be fed by their mothers in the nest for approximately 3 weeks. The chicks leave the nest about 20 days after hatching and reach sexual maturity at 1 year of age. In a single breeding season a female may have several broods.

Notes of Interest:

While hummingbirds don’t require a source of water for drinking, providing a water feature in your garden may help attract these beautiful birds. Including a fountain, pond, birdbath, waterfall or mister in your garden may increase insect populations and make your space more attractive.

Ruby-Throated Hummingbirds were a prized specimen in the nineteenth century due to their beautiful plumage. Although these birds were commonly hunted and a coveted prize, this species never became threatened and numbers stayed strong and stable16.

Footnotes

1. http://animaldiversity.ummz.umich.edu/accounts/Archilochus_colubris/
2. http://plants.usda.gov/pollinators/Ruby-throated_hummingbird.pdf
3. http://www.wvu.edu/~agexten/wildlife/hummer.htm
4. http://animaldiversity.ummz.umich.edu/accounts/Archilochus_colubris/
5. http://animaldiversity.ummz.umich.edu/accounts/Archilochus_colubris/
6. http://animaldiversity.ummz.umich.edu/accounts/Archilochus_colubris/
7. http://animaldiversity.ummz.umich.edu/accounts/Archilochus_colubris/
8. http://plants.usda.gov/pollinators/Ruby-throated_hummingbird.pdf
9. http://plants.usda.gov/pollinators/Ruby-throated_hummingbird.pdf
10. http://www.wvu.edu/~agexten/wildlife/hummer.htm
11. http://plants.usda.gov/pollinators/Ruby-throated_hummingbird.pdf
12. http://www.wvu.edu/~agexten/wildlife/hummer.htm
13. http://www.wvu.edu/~agexten/wildlife/hummer.htm
14. http://plants.usda.gov/pollinators/Ruby-throated_hummingbird.pdf
15. http://animaldiversity.ummz.umich.edu/accounts/Archilochus_colubris/
16. http://animaldiversity.ummz.umich.edu/accounts/Archilochus_colubris/

http://animals.nationalgeographic.com/animals/birds/ruby-throat-hummingbird/
http://plants.usda.gov/pollinators/Ruby-throated_hummingbird.pdf
http://www.wvu.edu/~agexten/wildlife/hummer.htm
http://animaldiversity.ummz.umich.edu/accounts/Archiloch

Back to Birds page

Rainbow Trout – Oncorhynchus mykiss, facts

Rainbow Trout

rainbow trout are fantastic game fish

General:

Members of the salmon family, Rainbow Trout, Oncorhynchus mykiss, are an anadromous species, migrating up-river to spawn. They are native to cool, fresh water, thriving in habitats that do not exceed 70F. Their preference in habitat makes them indicative of clean, clear waters. Rainbow Trout are one of the most popular sporting fish and as a result, are commonly bred and introduced into non-native regions. Alternate names, associated with this species, include Redband Trout, Coastal Rainbow and Steelheads.

Description:

With an average lifespan in the wild of 4 to 6 years, Rainbow Trout may grow to an adult size of 20” to 30” and reach an average weight of 2 to 8 lbs. However, some Rainbow Trout have been known to grow as large as 48” and weigh up to 30 lbs. in freshwater and 40 lbs. or greater in saltwater1. The body of the Rainbow Trout, like the common Salmon, is torpedo shaped, featuring a squared, forked tail with 10 to 12 anal rays, and an adipose fin. Differences in geographic habitation can result in variations in coloration and increased concentrations in anal rays. Other physical variations may be brought on by season, such as the hooked jaw, or kype, seen on male fish during the spawning season2.
Coloration is determined by geography, age and reproductive activity. Typically, Rainbow Trout display a predominantly blue-green or yellow-green coloring, providing camouflage against river and lakebeds. However, Rainbow Trout may turn silver while they spend time in salt water. Distinguishing features include red/pink markings running lengthwise on the sides, a silvery-white underside, white mouth and gums, and black speckling across the fins and back.

Location:

Rainbow Trout are native to North America, found in waters west of the Rockies, spanning north to Alaska and south to Mexico. Geographic populations are commonly identified by distinct names. The term Redband typically refers to Rainbow Trout living east of the Cascade Mountains in the U.S. and in the Upper Fraser River of British Columbia. Steelheads are Rainbow Trout that migrate to the Pacific as juveniles, spending time in saltwater before returning to freshwater to spawn3.

Due to their popularity as a sport fish and their ability to thrive in hatcheries, the Rainbow trout has been introduced to streams, rivers and lakes one every continent except for Antarctica, gaining this species distinction as invasive in certain locations. In the United States, there are introduced populations in 47 states, extending from the Great Lakes region, to south central Canada to the Great Plains east of the Rockies, and southwestern Mexico4.

Habitat:

Rainbow Trout live in fresh, cool waters and require a temperature not exceeding 70 for survival. These freshwater bodies include headwaters, creeks, rivers, lakes, estuaries, and oceans. Preferred habitats are complex, including features that provide protection, feeding opportunities and habitat stabilization for the trout. This diverse ecosystem is comprised of submerged boulders and wood, overhanging vegetation, root masses, and beds of aquatic plants and clean gravel, interspersed between turbulent runs, slow-flowing pools, and deep water. Because trout are solitary in nature, these features also create barriers between habitats, allowing Rainbow Trout to establish territories within close proximity of other populations.

Adult Steelheads (‘sea-run rainbow trout,’) have been known to follow fresh water routes to the Pacific, spending up to several years in an oceanic habitat before returning to fresh water to spawn.

A large percentage of native Rainbow Trout habitats have been compromised or lost due to many factors, including soil erosion, loss of riparian vegetation (that found growing along banks,) logging, mining, pollution due to agricultural and municipal development, and dam and road construction. In addition to loss of habitats, these factors also damage migratory routes, hindering upstream migration during the spawning season. These factors have lead to a reduction of native Rainbow Trout populations, forcing nine populations of Steelheads to the federal endangered species list.

Diet:

Rainbow trout are opportunistic and migratory feeders5. Their carnivorous diets consist of aquatic and terrestrial items, including Insects, crustaceans, small fish, plankton, leeches, mollusks, and fish eggs. When food supplies are limited, Rainbow Trout have been known to travel long distances in search of new sources.

Reproduction:

Rainbow Trout typically spawn in the spring and early summer, seeking out stream riffles downstream from pools, lake inlet or outlet streams or main river channels and tributaries. During the spawning season Steelhead trout have been known to migrate from the ocean to the freshwater where they hatched, identifying them as an anadromous or migratory species. Female Rainbow Trout seek out moving water over clean, sediment-free gravel, ranging from ½” to 3” in diameter, to build their nests. The female will use her tail to dig a shallow pit, called a redd, depositing a portion of her eggs to be fertilized by a male. After the first nest has been fertilized and covered with gravel, the female will dig another redd upstream, varying the water depth and velocity of the location to increase the survival rate of the eggs. After fertilization, the eggs require consistent temperatures of around 55F and continuous oxygenation through the clean gravel and hatch within 21 days6. Young trout will remain in the gravel from which they hatched until yolk reserves are depleted, emerging to search for new food sources7.

Rainbow Trout that have been introduced to non-native environments have a diminished rate of reproduction due to improper temperatures, and spawning environments. Because of this, states, including Ohio and Texas, must continually restock trout in their freshwaters to provide fisherman with this species. The Ohio Division of Wildlife introduces young trout into Lake Erie tributaries, where they will live for 1 to 2 years before migrating to the lake. The adult trout will live in the lake for up to several years, if allusive to fisherman, before returning to the tributaries and heading upstream to attempt to spawn8.

Rainbow Trout Fishing: The Rainbow Trout’s history with fisherman has made it one of “the top five sport fishes in North America, and it is considered by many to be the most important game fish west of the Rocky Mountains” 9.

“To catch a rainbow trout, an angler needs to be aware of the fish’s behavior in different water conditions. In streams, rainbow trout tend to select areas with gravel or rocky bottom that have cover such as boulders, logs or deep water nearby. In ponds and lakes, rainbow trout tend to swim around looking for food, especially near cover such as a weed line.

A variety if techniques can be used to catch rainbow trout: bait, artificials and fly fishing. When bait fishing, size 6-10 baitholder hooks and 4-8 lb. test line are best to use to suspend the bait in the water or split shot can be used to keep the bait on the bottom. Baits commonly used are worms, minnows, corn, crickets, salmon eggs or commercially produced baits such as Berkley Power Bait.

Fishing with artificials is a technique that uses a non-food item to imitate a food item. Spinner and spoons 1/32-1/8 oz. are commonly used for trout. They are made of metal and imitate a baitfish. Artificials can either be cast out and retrieved or trolled. A piece of bait can be added to an artificial to enhance its attractiveness” 10.

Notes of Interest:

Symbol of: Washington State

The largest rainbow trout on record weighed 57 lbs (25.8 kg) and was estimated to be 11 years old11.

Footnotes

1. http://www.tpwd.state.tx.us/huntwild/wild/species/rbt/
2. www.dnr.state.oh.us/LinkClick.aspx?link=6733&tabid=6518
3. http://www.fws.gov/northeast/wssnfh/pdfs/RAINBOW1.pdf
4. http://www.tpwd.state.tx.us/huntwild/wild/species/rbt/
5. http://www.fws.gov/northeast/wssnfh/pdfs/RAINBOW1.pdf
6. http://www.tpwd.state.tx.us/huntwild/wild/species/rbt/
7. www.dnr.state.oh.us/LinkClick.aspx?link=6733&tabid=6518
8. www.dnr.state.oh.us/LinkClick.aspx?link=6733&tabid=6518
9. http://www.fws.gov/northeast/wssnfh/pdfs/RAINBOW1.pdf
10. http://www.dec.ny.gov/docs/regions_pdf/rainbowtrout3.pdf
11. http://animals.nationalgeographic.com/animals/fish/rainbow-trout/

“Rainbow Trout.” National Geographic. National Geographic Society, 1996-2013. Web. 26 Feb. 2013.
http://animals.nationalgeographic.com/animals/fish/rainbow-trout/

“Rainbow Trout (Oncorhynchus mykiss).” U.S. Fish and Wildlife Service. Version 13. United States Department of Agrictulture: Natural Resources Conservation Service, May 2000. Web. 26 Feb. 2013.
http://www.fws.gov/northeast/wssnfh/pdfs/RAINBOW1.pdf

“Rainbow Trout.” ODNR Division of Wildlife. Ohio Department of Natural Resources. Web. 26 Feb. 2013.
www.dnr.state.oh.us/LinkClick.aspx?link=6733&tabid=6518

“Rainbow Trout (Oncorhynchus mykiss).” Texas Parks and Wildlife. Texas Parks and Wildlife Department. Web. 26 Feb. 2013.

http://www.tpwd.state.tx.us/huntwild/wild/species/rbt/

“Fishing for Rainbow Trout.” New York Department of Environmental Conservation. Web. 26 Feb 2013.
http://www.dec.ny.gov/docs/regions_pdf/rainbowtrout3.pdf
Current distribution of Rainbow Trout, including native habitats and domesticate populations. Photo Courtesy of http://www.fws.gov/northeast/wssnfh/pdfs/RAINBOW1.pdf

 

Back to wildlife – fish page

Garter snake – Thamnophis sirtalis, Facts

 Common garter snakes are highly variable in color pattern.
Picture taken by steve hillebrand

General: The Common garter snake, Thamnophis sirtalis, is one of the most common species of snake in their native habitats across much of North America. This non-venomous, cold-blooded snake is highly adaptable, thriving in urban and suburban environments and gardens, much to the dismay of the gardeners.

Description: Common garter snakes are an abundant, cold-blooded species exhibiting high levels of variation in coloration and appearance. Dozens of subspecies that have been identified by distinct color variations; however, variation in color has been found within populations, indicating that coloration alone may not be enough to identify a subspecies1.

Common garter snakes grow throughout the duration of their lives and are, on average, 18” to 26” in length but may grow as long as 49”2. Males and females are similar in coloration but males are smaller than females with longer tails relative to their size. The head, compared to the neck and body, is wide. Scales of the Common garter snake are keeled, meaning there is an elevated ridge running the length of each scale3. Body coloration may range from black, red, brown, gray to green.

Populations living in Florida and southern Georgia generally have bluish coloration on their bodies4. The underside, chin and throat (generally similar in color to the stripes on the body) may be green, blue-gray, green, or white, occasionally with black spots. There are typically three stripes running the length of the body on scales 2 and 3 (ranging from yellow, brown, blue, orange, gray, green, or white in color,) the middle stripe running down the center of the back. These stripes may be solid or may become undefined or entirely absent. In some specimens, two rows may join to form a thick bar or may become checkered or spotted in appearance5. Some populations of Common garter snakes exhibit red or orange coloration between the scales. This coloration may extend to the tips of the scales. The top of the head is generally dark with a pair of spots that are light or almost white in color. The eyes are large, relative to the size of the head. Upper lip scales are marked by dark vertical bars and the tongue is red and tipped in black.

Common garter snakes live an average of 2 years in the wild and 6 to 10 years in captivity. One Common garter snake living in captivity survived to 20 years of age6.

Since Common garter snakes are cold blooded, they must use thermoregulation to maintain an appropriate body temperature of 28° to 32° C7. To do this, snakes bask in sunlight during the morning and as body temperatures fall during the day, snakes become less active. Despite Common garter snakes being a solitary species, they are known to gather at night to sleep in groups to avoid becoming too cold. Common garter snakes can be active throughout the year and may be seen basking atop snow on warm winter days. This particular species is active across a greater temperature range than many other species of snakes due to a greater tolerance of cold, enabling one of the shortest hibernation periods of all snake species in nearctic habitats. Common garter snakes hibernate in large numbers during the winter, from October to early April, in natural cavities (such as crayfish or mammal burrows or ant mounds,) under debris such as rocks or tree stumps, in dams, or on hillsides. Sleeping in tightly coiled groups allows snakes to maintain body temperatures. Hibernation sites are different from summer grounds (used for feeding and breeding,) and snakes have been known to travel great distances from one site to the other.
Common garter snakes use touch and smell to communicate with one another, generally for reproductive purposes. Before mating, males secrete pheromones to attract females coming out of hibernation. Snakes use their tongues to sample chemicals from the air (including these pheromones,) using a specialized organ located on the roof of the mouth to decipher these chemicals. Common garter snakes are also able to sense vibrations and have developed vision8.

Habitat: Common garter snakes inhabit a variety of moist environments, such as woodlands, marshes and meadows. They prefer maintaining close proximity to water and cover under grass or brush, opting for pond or lake edges, streams, or ditches. In the case that water is not readily available, Common garter snakes have been known to travel long distances to locate a new source.

A highly adaptable species, Common garter snakes can survive extreme conditions9. Their adaptability allows them to thrive in urban and suburban settings.

Within their native habitats, Common garter snakes fall prey to many predators, including snapping turtles, foxes, squirrels, great blue herons, hawks, larger snakes, skunks, raccoons, opossum, American crows, bullfrogs and large fish. To avoid predators, Common garter snakes may hide in grass stripes (using their strips as camouflage,) or flee to water, but when attacked, they tend to coil to appear larger, strike and bite10. When caught, Common garter snakes release an unpleasant secretion from glands located at the base of the tail.

Threats: Common garter snakes are considered a low risk species; however, certain threats exist that are detrimental to population numbers. Urbanization has lead to a loss of the Common garter snake’s native habitats. Pesticides and chemicals also damage habitats. Common garter snakes have also experienced a decrease in food supplies, due to disease and competition by invasive species. Snakes living in developed areas often fall prey to dogs, cats, automobiles or lawnmowers and face the risk of being captured for domestication.

Location: Common garter snakes reside in the nearctic region, and may be found in a variety of habitats across much of North America, including woodlands, marshes, meadows, and hillsides. Populations may be found as far south as Florida’s western coast on the Gulf of Mexico, north to British Columbia, and west to California. The Common garter snake is generally absent from arid environments like the American Southwest, although several isolated populations exist in New Mexico and northern areas of Mexico11.

Diet: Common garter snakes are low-level predators, feeding mainly on earthworms and amphibians. Their diets also include insects, frogs, toads, salamanders, snails, leeches, slugs, crayfish, fish, tadpoles, snakes, baby birds and bird eggs, small lizards, and small mammals (such as mice.) These snakes are skilled swimmers, swimming slowly and locating prey with their highly developed senses of smell and sight. They capture prey using a variety of hunting methods, including craning, peering, and ambushing12. The saliva of the Common garter snake is slightly toxic, partially immobilizing their small prey, making it easier for the snake to swallow their meal whole. The quick reflexes and sharp teeth of the Common garter snake make them a well-honed predator in their habitats.

Toads and some other amphibians emit toxic chemicals to ward off predators; however, the Common garter snake is one of the few species able to consume these animals, unaffected by the chemicals.

Reproduction: The Common garter snake is a viviparous species, meaning that it bears live young. Mating occurs in the spring, immediately after snakes emerge from hibernation dens. The males exit first, surrounding the females as they emerge, secreting pheromones that will attract them. The females select their mate and as mating begins, snakes coil together, forming a breeding ball. After mating, females return to their summer habitats to feed and locate appropriate birthing areas. The males stay near the hibernation den to try and mate again with remaining females. Some females may chose not to mate in a particular season since they have the ability to store sperm from previous mating13.

Gestation lasts for 8 to 12 weeks, as young snakes are incubated in the female’s lower abdomen. Females typically give birth to litters containing 10 to 80 young snakes that are 5” to 9” in length14. Young snakes, similar in appearance to adults, are born between late July and October and are immediately independent, responsible for finding their own food and survival. The young tend to remain in close proximity to their mothers for up to a few days despite the mother offering no care15. Common garter snakes grow quickly and reach sexual maturity in 1.5 to 2 years (males generally reaching sexual maturity first.)

Notes of Interest

Despite often being feared, Common garter snakes should be a welcomed part of any garden as they aid in controlling insect and pest populations.

Common garter snakes may be tamed with appropriate handling, resulting in their popularity as pets.

The saliva of the Common garter snake may cause an allergic reaction in individuals who have handled a snake or been bitten16.

The San Francisco garter snake (Thamnophis sirtalis tetrataenia,) a subspecies of the Common garter snake, is an endangered species and in 1967 was placed on the U.S. and California Endangered Species lists.

Footnotes

1. http://www.arkive.org/common-garter-snake/thamnophis-sirtalis/
2. http://srelherp.uga.edu/snakes/thasir.htm
3. http://animaldiversity.ummz.umich.edu/accounts/Thamnophis_sirtalis/
4. http://srelherp.uga.edu/snakes/thasir.htm
5. http://www.arkive.org/common-garter-snake/thamnophis-sirtalis/
6. http://animaldiversity.ummz.umich.edu/accounts/Thamnophis_sirtalis/
7. http://animaldiversity.ummz.umich.edu/accounts/Thamnophis_sirtalis/
8. http://animaldiversity.ummz.umich.edu/accounts/Thamnophis_sirtalis/
9. http://animaldiversity.ummz.umich.edu/accounts/Thamnophis_sirtalis/
10. http://animaldiversity.ummz.umich.edu/accounts/Thamnophis_sirtalis/
11. http://animaldiversity.ummz.umich.edu/accounts/Thamnophis_sirtalis/
12. http://animaldiversity.ummz.umich.edu/accounts/Thamnophis_sirtalis/
13. http://animaldiversity.ummz.umich.edu/accounts/Thamnophis_sirtalis/
14. http://animaldiversity.ummz.umich.edu/accounts/Thamnophis_sirtalis/
15. http://animaldiversity.ummz.umich.edu/accounts/Thamnophis_sirtalis/
16. http://animaldiversity.ummz.umich.edu/accounts/Thamnophis_sirtalis/

http://srelherp.uga.edu/snakes/thasir.htm
http://animaldiversity.ummz.umich.edu/accounts/Thamnophis_sirtalis/
http://www.inhs.illinois.edu/animals_plants/herps/species/th_sirtali.html
http://www.arkive.org/common-garter-snake/thamnophis-sirtalis/
http://www.fcps.edu/islandcreekes/ecology/eastern_garter_snake.htm

Striped Skunk – Mephitis mephitis, Information

General: The Striped Skunk (Mephitis mephitis) is an easily identifiable member of the STRIPED SKUNK: a common North American skunk (Mephitis mephitis) usually with white on the top of the head that extends posteriorlyweasel family, known for its graphic coloration and extreme odor used for defensive purposes (mephitis meaning “noxious vapor” in Latin.) This shy nocturnal animal is an opportunistic feeder that can often be spotted in backyards searching for its next meal. This is an abundant species with populations across much of North America and is listed as Least Concern on the IUCN Red List.

Description: Striped skunks are known for their graphic black and white coloration. Their all-black bodies are marked with two bold white stripes running the length of the back, originating on the head where they meet in a triangular shape to form a ‘white cap.’ A third white stripe runs between the eyes, from the forehead to the base of the snout. Bushy tails are 6” to 12” in length and are usually a mottled combination of black and white hairs, although the solid stripes may extend onto the tail. Stripe width and length are determined on an individual basis. Color patterns may vary, resulting in the identification of four subspecies. These subspecies typically occur because of geographic barriers1.

Adults grow to an average length of 22” to 32” and a weight of 2.5lbs. to 10lbs., comparable to a housecat, males reaching a larger mature size than females. Striped skunks have small heads with small features and short legs with plantigrade feet and five partially webbed toes2. The front toes have long claws that aid in digging. Their short legs do not allow for running, instead Striped skunks move with distinctive waddles3.
Wild Striped skunks have a life expectancy of 2 to 3 years. In some regions, nearly 90% of skunks perish during their first year. Striped skunks living in captivity have survived as long as 15 years4.

Striped skunks are nocturnal, emerging from their burrows at dusk to search for food. During the day they reside in protective dens, often built using another animal’s abandoned burrow, such as a fox or woodchuck. Striped skunks may also build their own den in the ground or a hollow log or under a building, using their long claws to excavate5. These dens may contain up to five entrances and multiple chambers.
Striped skunks enter a period of inactivity from the late fall to March. Communal winter dens accommodate several females with their young and, on occasion, a male (although males usually live in a separate, solitary den.) Males tend to emerge on mild winter days in search of food, while females remain inactive throughout this period.

Skunks are notorious for their mechanism of defense. Because their coloration offers them no camouflage in their native habitats, they require a physical defense that develops when they are just a few weeks old. When facing an extreme or mortal threat, these animals use two glands located on either side of the anus to accurately spray an intense-smelling compound up to 15’ (the smell can travel for up to a mile.) This foul oily spray is directed at threats or predators and may cause extreme discomfort in the eyes or respiratory system, and nausea. Before spraying, Striped skunks display a series of warning behaviors to ward off predators, including hissing, stomping, arching the back, and erecting the tail.
Striped skunks use scent to announce their presence and/or reproductive status to other individuals, since they have excellent senses of smell. They may also use changes in posture and a variety of sounds to communicate (their good sense of hearing allows them to register hisses, screams, squeals, and chattering made by other skunks6). Skunks are known to have poor vision, resulting in many collisions with automobiles.

Habitat: Striped skunks prefer open areas in close proximity to water. Habitats include woods, grassy fields, agricultural clearings, parks and suburban areas. In their native habitats Striped skunks have several predators, including owls, hawks, bobcats, foxes, coyotes, and dogs.

Location: Striped skunks are native to the nearctic region, found across most of North American, from central Canada to northern Mexico7.

Diet: Striped skunks are opportunistic feeders, scavenging for a diet that varies based on season. As omnivores, skunks’ diets include insects (with beetles and beetle larvae, caterpillars, ants, wasps, grasshoppers, crickets, bees, millipedes and centipedes making up roughly 70% of their diets8,) worms, snails, salamanders, crustaceans, turtle eggs, ground-nesting birds and their eggs, slugs, frogs, mice, squirrels, shrews, small rabbits and snakes, fish and fruits and vegetation (including berries, grass, leaves, buds, carrion and nuts)9. Striped skunks commonly dig in search of food (such as grubs,) leaving shallow divots in a lawn that resemble those dug by squirrels.

Reproduction: Striped skunks are a solitary species and typically only interact when mating in the late winter or early spring. Female skunks are monestrous but may have a second estrus in the case of a failed initial pregnancy and males are polygamous, usually seeking out several partners in one mating season. Females build a nest of dried leaves, grass, and weeds usually located in one of the chambers in her den. The nest may also be located under a thicket of dense vegetation, under a rock, or in a burrow. Females nurture the unborn internally, with gestation lasting between 60 and 77 days. Litters contain anywhere from 1 to 10 young (but on average contain 4 or 5,) that are born blind, deaf, and immature, weighing only 33g10. Females provide the helpless young with milk for a month after birth while males provide no care. After about 6 weeks in the den, the young will begin following their mother out hunting and will continue doing so until fully grown, reaching sexual maturity in 10 months11.

Encounters of the Skunk Kind…

It is important to remember that skunks use their spray defense as a last resort, when they feel they or their young are being gravely threatened. Avoiding these animals and knowing the warning signs are your best defenses against you or your pets getting sprayed. The first step is being aware of your surroundings, especially at night when these animals are most active. Keep your pets on a leash or restrained in a fenced-in yard away from areas where skunks may have dens or be feeding. Limit pets’ outdoor-time at night and make sure to supervise them. Also consider eliminating areas that may attract skunks, such as abandoned animal dens or cavities in the ground, open-access to sheds or garages, and animal food storage. If a skunk is encountered, try and remain calm. These generally easy-going animals may ignore humans and other animals all together if they don’t feel threatened. If you stand still and passive, the skunk may wander away from the area. Calmly walk away and remove pets from the area.

You can tell if a skunk feels threatened by looking for these signs:

• Hissing
• Stamping feet and forward lunges
• Raised tail
• Turning of the posterior in your direction

If you or your pets are unfortunate enough to be sprayed, several steps should be taken to avoid physical discomfort and ease the potency of the smell. If the sulfur-alcohol compound12 emitted by the skunk has gotten into your or your pet’s face, immediate flushing with clean water or a saline solution is necessary (making sure to flush your pet’s eyes, nose, and mouth.) This compound may cause severe discomfort and possibly temporary blindness. If your pet continues to rub his/her eyes after rinsing, contact your veterinarian and try to prevent additional rubbing (as this may cause more trauma to the eyes.) If this compound is inhaled (at close range,) it may cause respiratory inflammation and discomfort and extreme nausea13. Proper attention should be sought from medical professionals for you or your pet if symptoms persist or are severe.

In order to eliminate the strong odor, the chemicals emitted by the skunk must be neutralized. The following mixture may be applied to your skin, hair, some clothing, and your pet:

1 quart 3% hydrogen peroxide
¼ cup baking soda
1-2 tsp. liquid dish soap

Combine these ingredients and apply immediately using rubber gloves, avoiding your or your pets’ eyes. Keep in mind this mixture will bubble. Rinse, and repeat. For external use only. Keep in mind, hydrogen peroxide is a bleaching agent and should not be left on for more than 2 minutes.

Discard any remaining mixture. Do not store in a closed container because oxygen released will cause the container to explode14.

If possible, discard any contaminated clothing since this oily mixture soaks in to many fabrics. The above mixture may be applied to some clothing but could bleach colors. Contact your local dry cleaner regarding garments you wish to have washed.
If clothing, your home, or other items have absorbed the smell indirectly, you may wash using a solution of household bleach to neutralize odors (1 cup bleach per gallon of water.)
Commercial cleaning solutions, shampoos, or sprays (containing neutroleum alpha) may be available at your veterinarian’s office or your local store that specifically target skunk odors15.

*If you encounter a skunk during the day it is important to contact the appropriate authorities. Skunks are primarily a nocturnal species and abnormal activity during the day could indicate a rabid animal. If you or your pet is bitten (which is uncommon but can happen,) you should immediately contact your doctor or veterinarian, as well as your local health department.

Notes of Interest:

Skunks are one of the four primary carriers of the Rabies virus. Other primary carriers include bats, raccoons, and foxes16.

Before writing skunks off completely, consider their positive attributes, including their tendency to aid in pest control, feeding on mice, squirrels, moles, caterpillars and grubs.

While skunks secrete a very undesirable smell when threatened, their regular musk is a common ingredient in perfumes17.

A member of the weasel family (along with minks, and ermines,) the skunk has a thick coat of glossy fur. Historically, their hides were sought after by the fur industry. In recent decades, this fur has seen a decline in value18.

Skunks may be domesticated and some households choose to keep skunks as pets (having the scent glands removed.) This practice, however, is illegal in many states due to this species’ tendency to carry the rabies virus.

Footnotes

1. http://animaldiversity.ummz.umich.edu/accounts/Mephitis_mephitis/
2. http://animaldiversity.ummz.umich.edu/accounts/Mephitis_mephitis/
3. http://www.fcps.edu/islandcreekes/ecology/striped_skunk.htm
4. http://animaldiversity.ummz.umich.edu/accounts/Mephitis_mephitis/
5. http://www.fcps.edu/islandcreekes/ecology/striped_skunk.htm
6. http://animaldiversity.ummz.umich.edu/accounts/Mephitis_mephitis/
7. http://animaldiversity.ummz.umich.edu/accounts/Mephitis_mephitis/
8. http://animaldiversity.ummz.umich.edu/accounts/Mephitis_mephitis/
9. http://www.fcps.edu/islandcreekes/ecology/striped_skunk.htm
10. http://animaldiversity.ummz.umich.edu/accounts/Mephitis_mephitis/
11. http://www.fcps.edu/islandcreekes/ecology/striped_skunk.htm
12. http://www.humanesociety.org/animals/skunks/tips/solving_problems_skunks.html
13. http://www.weather.com/outlook/homeandgarden/pets/articles/d82
14. http://www.humanesociety.org/animals/skunks/tips/solving_problems_skunks.html
15. http://www.humanesociety.org/animals/skunks/tips/solving_problems_skunks.html
16. http://www.humanesociety.org/animals/skunks/tips/solving_problems_skunks.html
17. http://www.fcps.edu/islandcreekes/ecology/striped_skunk.htm
18. http://animaldiversity.ummz.umich.edu/accounts/Mephitis_mephitis/

http://www.fcps.edu/islandcreekes/ecology/striped_skunk.htm
http://animaldiversity.ummz.umich.edu/accounts/Mephitis_mephitis/
http://www.tpwd.state.tx.us/huntwild/wild/species/skunk/
http://www.weather.com/outlook/homeandgarden/pets/articles/d82
http://voices.yahoo.com/what-if-re-sprayed-skunk-6299072.html
http://www.humanesociety.org/animals/skunks/tips/solving_problems_skunks.html
http://animals.howstuffworks.com/animal-facts/10-things-to-do-if-youve-been-skunked10.htm
http://www.psu.edu/dept/nkbiology/naturetrail/speciespages/stripedskunk.htm

Red Squirrel – Tamiasciurus hudsonicus Information

General: The Red Squirrel (Tamiasciurus hudsonicus) may be distinguished by its small size The red squirrel is most active in the early morning and its extreme territorial behavior, relative to other species of squirrels. Classified by the IUCN Red List as Least Concern, this widespread species is a common staple in ecosystems across North America. Spending its time hoarding massive amounts of cones and seeds for cold winter months, these squirrels are territorial of their nests and stockpiles and play an important role in seed distribution in their forest habitats.

Description: The Red Squirrel may be identified from other squirrels by their color, territorial behavior, and small size. Male and female squirrels are of a similar size and coloration, although regional variations can include color and size differences. The dorsal coloration can range from dark reddish brown, to brown or reddish-grey, contrasted by white or cream undersides. Unique markings include dark lateral lines on the body (which turn nearly black in the summer, separating the light underside from the dark upper,) white eye- rings, and tufted ears (evident during the winter.) The tail, flatter and 30% smaller than that of gray squirrels, may be yellowish-grey or deep red, with white or yellow tips on the hair and banded by black the length of the entire tail. Red Squirrels may weigh 197 to 282 grams, and be 6.5” to 9” long less than half the size of a fox squirrel. The tail makes up most of the body length, ranging from 3.5” to 6.5” in length. The Red Squirrel molts twice a year, once in the spring (between March and August, starting at the nose and ending at the posterior,) and once in the fall between August and December (starting at the tail and ending at the front legs)1. The tail of the Red Squirrel only molts in the fall. The body of the Red Squirrel is suited for climbing, with powerful rear legs and curved front claws used to grip bark.

In the wild, the Red Squirrel may live up to ten years; however, fewer than 25% of Red Squirrels live past the first year. The average lifespan of the Red Squirrel is three to seven years2 in the wild and five years in captivity.

The Red Squirrel has highly developed senses of smell, hearing and sight, making them well suited for foraging, climbing, and alluding predators.

Health: Red Squirrels are susceptible to a number of physical ailments, including parasites, fungal diseases, and viruses. Endoparasites (internal) include nematodes, tapeworms, tularemia bacteria, and sarocysts. Ectoparasties (external) include mites, ticks, fleas, and botfly larvae. They may develop a fungal lung disease infection by hosting adiaspiromycosis3. They are also prone to a number of viruses, including the silverwater virus, California encephalitis virus and Powassan virus4.

Behavior: Red Squirrels are a primarily diurnal species, most active during the early morning and in the late afternoon. During the fall red squirrels are generally more active in preparation of the winter.

During the winter, squirrels take advantage of mid-day temperature spikes, using this time to forage. These squirrels do not hibernate, despite common belief. Instead, they slow their activity levels according to temperatures. During the winter it is uncommon for a squirrel to stay inside a nest for more than one day without leaving to search for food. As temperatures dip below freezing, Red Squirrels become relatively inactive, taking refuge in a tree cavity, underground, or in a loosely constructed nest in a tree5.

The Red Squirrel is one of the most territorial squirrels of North America, using a variety of noises to defend their territory and food or fend off threats from predators. They are also very agile making them difficult to capture, but if cornered, they will defend themselves6. The Red Squirrel is known for its communication abilities, with noises ranging from rattles, chirps, screeches, and growls, to buzzes7. During mating season, males will use low aggressive, territorial calls to fend off other males. In response to threats, squirrels will give-off specific calls depending on the type of predator, a high frequency call for aerial attackers, or a sharp, bark for predators on the ground8.

In addition to vocal communication, Red Squirrels also use scent marking to aid in protection of territory or defense from predators, including snakes, birds of prey, and a variety of mammals9.

Habitat: Red Squirrels are primarily an arboreal species, inhabiting boreal coniferous, deciduous, or mixed northern forests. They may also reside in temperate or polar environments, in second-growth forests, suburban or urban areas, assuming coniferous trees are present with interlocking canopies and fungal resources10. Red Squirrels are found in a variety of ecosystems, with some populations living in mountainous regions up to 2500’. Territories, on average, are 2400 to 48000 square meters and are fiercely defended11.

Location: The Red Squirrel can be found across North America, with populations widely spread in Canada, Alaska, and parts of the United States, including the Rocky and Appalachian Mountains, and the Eastern United States as far south as northern Georgia12. 25 subspecies of the Red Squirrel have been identified. Isolated populations of the Red Squirrel include a subspecies in Arizona’s Pinaleño Mountains and an introduced population on the island of Newfoundland13.

Diet: Because the Red Squirrel inhabits areas with resource pulse systems (habitats with extreme seasonal variation in food supplies)14, they are opportunistic feeders who have been known to migrate in search of sustenance. These squirrels are primarily granivorous15, consuming a diet consisting mainly of conifer cones and seeds, and nuts. Their diets also include fruit, flowers, fungi, and buds, and when food supplies are low, will expand to include insects, bird eggs and hatchlings, and small vertebrates such as mice. Red Squirrels have also been observed feeding on sap, bark, and underlying tree tissue16.
Red Squirrels systematically harvest cones and seeds from pine trees and other conifers, collecting those with the highest energy density per cone first. The cones and seeds are cut from trees and stored in huge stockpiles, called middens. These food stores contain, on average, 2,000 to 4,000 cones and can be found in hollow stumps, at the bases of trees, underground, or under logs. Middens may contain upwards of 18,000 cones and be used by several generations of squirrels17. A typical sized midden holds enough food to last at least one or two seasons. Red Squirrels have also been known to use a process called scatter hoarding, hiding several small stockpiles of food rather than one large midden18. Because of their tendency to scatter food stores, Red Squirrels play an important part in seed distribution in their habitats.

Reproduction: Red Squirrels reach sexual maturity in one year and typically breed annually, following the cyclical production of conifer seeds and cones19. The breeding season lasts about 100 days, occurring in the spring. In warmer climates a second breeding season may occur in the late summer or early fall. Regional distribution causes variations in breeding times. For example, a second breeding season is common in the eastern United States, occurring in late July. Red Squirrels tend to be characterized as promiscuous in their mating but mating pairs do exist. Because of this behavior, an estrus female (in her period of ovulation) will be pursued by and mate with several males, participating in mating chases that can last up to several hours20. The dominant male will fend off the other males in the chase with physical displays of dominance or through audible communication. Estrus only lasts one day during the breeding season,21 and females will initiate copulation, which will occur several times during that afternoon. Gestation lasts, on average, 35 days. Litters may contain 1 to 8 offspring weighing just over 7 grams each22. The young are born naked and are weaned by 8 weeks old, although lactation occurs for 70 days23. By 18 weeks old the young are independent, moving away to establish their own territories. Sometimes, the mother will allot some or all of her territory to one or more of her young, moving away herself to establish a new territory. This act increases the success rate of her young.

Nests may be built in a number of locations, including tree hollows, cavities in the ground, in fallen logs or in tree limb junctions, although Red Squirrels prefer natural cavities. Nests are located within 100’ of food storage and are constructed of leaves, grass, moss, feathers, fur, or bark, depending on geographic location and available materials. When constructed in a tree, nests can be built from 6’ to 60’ off the ground.

Notes of Interest

Alternate names for the Red Squirrel include the North American Red Squirrel, Pine Squirrel, chickaree, and the Mount Graham Red Squirrel24.

The Mount Graham Red Squirrel is an isolated subspecies of the Red Squirrel consisting of one small population of approximately 250 squirrels. This subspecies was thought to be extinct in the 1950’s, but was rediscovered in the 1970’s25. This subspecies is endangered, according to the U.S. Fish and Wildlife Service.

The Red Squirrel faces a number of threats and certain populations and subspecies have experienced a decline in numbers due to harvesting for fur (the Red Squirrel is the third most harvested furbearer in Canada,) fragmentation of habitats due to forestry, construction of roads and civic development, forest fires, drought, and invasive species26.

Red Squirrels are a destructive species and may affect tree species as well as property. By stripping the bark and removing cones and buds from trees, these squirrels may inhibit the healthy growth of individual trees and tree populations. It has been determined that this species consumes 60% to 100% of cone crops in certain locations27. However, they also contribute to the distribution of seeds, leaving neglected stockpiles to germinate. Squirrels may also cause damage to property by nesting in homes or gnawing on items.

Red Squirrels have been known to bite humans when provoked28.

Footnotes

1. http://animaldiversity.ummz.umich.edu/accounts/Tamiasciurus_hudsonicus/
2. http://www.arkive.org/american-red-squirrel/tamiasciurus-hudsonicus/image-G99592.html
3. http://animaldiversity.ummz.umich.edu/accounts/Tamiasciurus_hudsonicus/
4. http://animaldiversity.ummz.umich.edu/accounts/Tamiasciurus_hudsonicus/
5. http://www.arkive.org/american-red-squirrel/tamiasciurus-hudsonicus/image-G99592.html
6. http://animaldiversity.ummz.umich.edu/accounts/Tamiasciurus_hudsonicus/
7. http://www.arkive.org/american-red-squirrel/tamiasciurus-hudsonicus/image-G99592.html
8. http://animaldiversity.ummz.umich.edu/accounts/Tamiasciurus_hudsonicus/
9. http://animaldiversity.ummz.umich.edu/accounts/Tamiasciurus_hudsonicus/
10. http://animaldiversity.ummz.umich.edu/accounts/Tamiasciurus_hudsonicus/
11. http://animaldiversity.ummz.umich.edu/accounts/Tamiasciurus_hudsonicus/
12. http://www.arkive.org/american-red-squirrel/tamiasciurus-hudsonicus/image-G99592.html
13. http://www.arkive.org/american-red-squirrel/tamiasciurus-hudsonicus/image-G99592.html
14. http://animaldiversity.ummz.umich.edu/accounts/Tamiasciurus_hudsonicus/
15. http://animaldiversity.ummz.umich.edu/accounts/Tamiasciurus_hudsonicus/
16. http://www.arkive.org/american-red-squirrel/tamiasciurus-hudsonicus/image-G99592.html
17. http://www.arkive.org/american-red-squirrel/tamiasciurus-hudsonicus/image-G99592.html
18. http://animaldiversity.ummz.umich.edu/accounts/Tamiasciurus_hudsonicus/
19. http://animaldiversity.ummz.umich.edu/accounts/Tamiasciurus_hudsonicus/
20. http://www.arkive.org/american-red-squirrel/tamiasciurus-hudsonicus/image-G99592.html
21. http://animaldiversity.ummz.umich.edu/accounts/Tamiasciurus_hudsonicus/
22. http://animaldiversity.ummz.umich.edu/accounts/Tamiasciurus_hudsonicus/
23. http://animaldiversity.ummz.umich.edu/accounts/Tamiasciurus_hudsonicus/
24. http://www.arkive.org/american-red-squirrel/tamiasciurus-hudsonicus/image-G99592.html
25. http://www.arkive.org/american-red-squirrel/tamiasciurus-hudsonicus/image-G99592.html
26. http://www.arkive.org/american-red-squirrel/tamiasciurus-hudsonicus/image-G99592.html
27. http://animaldiversity.ummz.umich.edu/accounts/Tamiasciurus_hudsonicus/
28. http://animaldiversity.ummz.umich.edu/accounts/Tamiasciurus_hudsonicus/

http://www.arkive.org/american-red-squirrel/tamiasciurus-hudsonicus/image-G99592.html
http://www.nhptv.org/natureworks/redsquirrel.htm
http://animaldiversity.ummz.umich.edu/accounts/Tamiasciurus_hudsonicus/

House Sparrow – Passer domesticus Information and Description

General: The House Sparrow (Passer domesticus) is one of the most common bird species in North America, although it is a non-native species. These sociable and tame birds can be The House Sparrow (Passer domesticus) is a bird of the sparrow family Passeridae, found in most parts of the worldspotted in backyards hopping along the ground pecking at seed as well as on city streets feeding on crumbs. This species has a long running relationship with humans and has come to rely heavily on human populations for survival. House Sparrows have healthy and stable populations across a wide geographic range and are listed as Least Concern on the IUCN Red List.

Description: House Sparrows are unrelated to other species of sparrows that are native to North America and, therefore, differ in appearance. They may be identified by their shorter, stockier appearances, accentuated by full chests, shorter tails and legs, large round heads and shorter, thicker beaks. House Sparrows reach a mature size of 5.9” to 6.7” in length and 27g to 29g in weight. Their wingspan, when full grown, is 7.5” to 9.8”1. Geographic variations exist due to the House Sparrows immense range. Colder climates tend to produce larger birds with shorter wings and legs, whereas populations with darker plumage tend to be found in humid climates2.

Coloration may differ between sexes and during different seasons. Both sexes generally have buff, brown and black stripes on their backs, although males tend to be more brightly colored, with gray heads, black patches or “bibs” on their necks and white cheeks. Females are generally dull tan-gray, with gray undersides, buff eye-stripes, and a bill that is more yellow than males. During the summer, breeding males will display a black bill, mask, throat and chest, a gray cap, and a white stripe on their shoulders. Their main coloring is a reddish-brown with black streaks. Non-breeding males lack the vibrant reddish-brown coloration because those feathers become obscured by gray feather tips. Non-breeding males also have less black on their throats and chests, and yellow at the base of their bills3. This seasonal variation is due to an annual molt. Juveniles are plain in color, in appearance to females.

House Sparrows are generally tame and sociable birds, within their flocks and with people, especially during the winter. Because these birds live in social communities, methods of communication have been developed to relay dominance, submissiveness, nervousness, courting and aggression. They often feed together to minimize predation and their flocks have social structures that are similar to that of chickens. Male House Sparrows with larger black throat patches tend to be dominant over males with smaller bibs. During the courting and breeding season females tend to be more assertive, but males are the dominant sex in the flock throughout the rest of the year. Nervousness is indicated by a flick of the tail. Aggression is communicated by a crouched posture with thrust-forward head, spread wings, erect tails and ruffled feathers (in extreme situations.) In a courting display, a male will puff up his chest and open his wings and tail, hopping stiffly and bowing up and down in front of the female4. In addition to social dominance and behavioral communication, House Sparrows are a noisy species that uses a number of simple vocalizations to verbalize warnings, threats and defense, or to attract a mate. The most common sounds include a chatter (often used by females toward her mate or to chase away competing females,) a cheep (used in a series to attract mates and in a flock to communicate submissiveness,) wheezy calls, and chirps.
House Sparrows tend to have more direct and higher flight than native species of sparrows. Their flight is continuous and lacks periods of gliding5. Because of their stature and short legs, House Sparrows can most often be seen hopping on the ground rather than walking.
House Sparrows tend to have life spans of just a few years. However, there are recorded instances of wild House Sparrows living as long as 13 to 15 years.

Habitat: House Sparrows tend to be found in areas inhabited or affected by humans, including cities, towns, suburbs, farms, and parks. Because of their dependency on humans, House Sparrows are unable to survive in areas such as uninhabited woodlands, alpine forests, grasslands, or deserts. In extreme climates House Sparrows must maintain a close proximity to human populations for survival.

In their habitats House Sparrows (and their eggs and young) are vulnerable to a number of predators, such as hawks, owls, cats, dogs, raccoons and snakes. House Sparrows tendency to forage in flocks increases their awareness and survival rates.

Location: House Sparrows are year round residents of their native environments of Eurasia and North Africa. Introduced, invasive populations are also non-migratory and thrive in South Africa, South America, New Zealand, Australia, and North America. Their lack of migration increases survival rates because of a diminished demand for energy and exposure to predators.
The House Sparrow was introduced to Brooklyn, New York in 1851, when 100 birds from England were released. This may have been done to control certain insect populations or to make the area more familiar to European immigrants. By the turn of the century, House Sparrow populations had spread to the Rocky Mountains. Additional populations were released in San Francisco and Salt Lake City in the 1870’s, expanding this species range across North America (excluding Alaska and northern parts of Canada6.)

Diet: House Sparrows are omnivorous ground foragers that spend much of their time hopping along the ground pecking at food. House Sparrows have also been known to steal food from larger species of birds and drink nectar from flowers. Their diets consist mainly of grain and seed (corn, oats, sorghum, wheat,) crumbs and food waste, ragweed, grasses, buckwheat, commercial birdseed, and insects.

Reproduction: House Sparrows are monogamous and form breeding pairs each season, with nesting beginning in late winter and courtship occurring in early spring. Nesting may begin only a few days before the first egg is laid. House Sparrows prefer to build their nests in manmade structures such as the walls of buildings, on streetlights, in nest boxes or in the eaves of houses. They have been known to evict other birds from their nests, destroying existing eggs and physically attacking the opposing birds. House Sparrows tend to reuse their nests. And have been known to aggressively defend their nesting areas.

Both males and females construct the nests by stuffing their nesting cavities with dry vegetation until the hole is nearly full and then lining the interior with softer materials such as string, paper, and feathers. House Sparrows often nest in close proximity to each other, the nests sometimes sharing a common wall.

House Sparrows may lay up to 4 broods in a year, each containing between 1 and 8 white/light-green/blue-white eggs, speckled with gray or brown and approximately 7/8” in length. Parents alternate incubating the eggs for a period of 10 to 14 days. Young chicks are born naked and uncoordinated, with closed eyes. During the nestling period of 10 to 14 days both parents feed the chicks through regurgitation. House Sparrows reach sexual maturity by around 9 months of age.

Notes of Interest:

House Sparrows enjoy dust baths and can often be spotted coating their bodies with dust and dirt. They also take baths in puddles or shallow water, using a similar flicking motion to coat their feathers.

Because House Sparrows are so numerous and tame, they are often the subject of avian biological studies and have been the subject of nearly 5,000 scientific papers7.

Although House Sparrows are common and numbers are stable, some populations have experienced a sharp decline, possibly due to farming practices, and changes in land-use. Despite this, they are not considered threatened and are not protected under any laws or regulations.

Footnotes

1. http://www.allaboutbirds.org/guide/house_sparrow/id
2. http://animals.nationalgeographic.com/animals/birding/house-sparrow/
3. http://www.allaboutbirds.org/guide/house_sparrow/id
4. http://www.allaboutbirds.org/guide/house_sparrow/id
5. http://animaldiversity.ummz.umich.edu/accounts/Passer_domesticus/
6. http://www.allaboutbirds.org/guide/house_sparrow/id
7. http://www.allaboutbirds.org/guide/house_sparrow/id

http://www.allaboutbirds.org/guide/house_sparrow/id
http://animals.nationalgeographic.com/animals/birding/house-sparrow/
http://animaldiversity.ummz.umich.edu/accounts/Passer_domesticus/
http://www.thepoultrysite.com/articles/848/understanding-and-control-of-house-sparrows