Disease and food shortage may also limit chipmunk populations but, once again, little is known about these factors.
Seed crop failures are likely to have a significant detrimental effect on chipmunks, which depend on stored food to survive the winter. Disease epidemics have not been reported from chipmunks but are known to occur in populations of mice and other rodents. Parasites, such as botfly larvae, tapeworms, fleas, mites, and probably lice, can have a debilitating effect and, on rare occasions, even cause death.
Chipmunks are important in the dispersal of seeds because of their habit of storing the seeds beneath the layer of decaying vegetation on the forest floor. Any buried seeds that are not consumed stand a better chance of germinating than those remaining on the surface litter. In this way, chipmunks assist in the spread of shrubs, trees, and other plants. If chipmunks are very abundant, they can prevent normal reforestation of some trees, especially pines, by eating their seeds. Occasionally chipmunks and other rodents are trapped to ensure adequate germination and growth of seedlings.
Poisoning is not an acceptable means of control because of the harmful effects on other wildlife, including gamebirds and songbirds. Much of the value of chipmunks lies in the pleasure they provide for campers, hikers, and anyone who enjoys the country. Our national and provincial parks and our summer cottages and trailers would be less interesting and less enjoyable without chipmunks dashing across forest trails or boldly helping themselves to food in campgrounds and picnic areas.
CWF's The Chipmunk. Henisch, B. Chipmunk portrait. Carnation Press, State College, Pennsylvania. Wishner, L. Eastern chipmunks.
Secrets of their solitary lives. Smithsonian Institution Press, Washington, D. All rights reserved. Aniskowicz, Photo: Tony Beck. The Northern Leopard Frog Lithobates pipiens is named for its leopard-like spots across its back and sides. Historically, these frogs were harvested for food frog legs and are still used today for dissection practice in biology class.
Northern Leopard Frogs are about the size of a plum, ranging from 7 to 12 centimetres. They have a variety of unique colour morphs, or genetic colour variations.
They can be different shades of green and brown with rounded black spots across its back and legs and can even appear with no spots at all known as a burnsi morph. They have white bellies and two light coloured dorsal back ridges.
Another pale line travels underneath the nostril, eye and tympanum, ending at the shoulder. The tympanum is an external hearing structure just behind and below the eye that looks like a small disk. Black pupils and golden irises make up their eyes. They are often confused with Pickerel Frogs Lithobates palustris ; whose spots are more squared then rounded and have a yellowish underbelly.
Male frogs are typically smaller than the females. Their average life span is two to four years in the wild, but up to nine years in captivity. Tadpoles are dark brown with tan tails. Lampreys are an amazing group of ancient fish species which first appeared around million years ago.
This means they evolved millions of years before the dinosaurs roamed the earth. There are about 39 species of lamprey currently described plus some additional landlocked populations and varieties.
In general, lamprey are one of three different life history types and are a combination of non-parasitic and parasitic species. Non-parasitic lamprey feed on organic material and detritus in the water column. Parasitic lamprey attach to other fish species to feed on their blood and tissues.
Most, 22 of the 39 species, are non-parasitic and spend their entire lives in freshwater. The remainder are either parasitic spending their whole life in freshwater or, parasitic and anadromous.
Anadromous parasitic lampreys grow in freshwater before migrating to the sea where they feed parasitically and then migrate back to freshwater to spawn. The Cowichan Lake lamprey Entosphenus macrostomus is a freshwater parasitic lamprey species. It has a worm or eel-like shape with two distinct dorsal fins and a small tail.
It is a slender fish reaching a maximum length of about mm. When they are getting ready to spawn they shrink in length and their dorsal fins overlap. Unlike many other fish species, when lampreys are getting ready to spawn you can tell the difference between males and females. Females develop fleshy folds on either side of their cloaca and an upturned tail. The males have a downturned tail and no fleshy folds. These seven gill pores are located one after another behind the eye.
There are several characteristics which are normally used to identify lamprey. Many of these are based on morphometrics or measurements, of or between various body parts like width of the eye or, distance between the eye and the snout.
Other identifying characteristics include body colour and the number and type of teeth. Some distinguishing characteristics of this species are the large mouth, called and oral disc and a large eye. This species also has unique dentition.
For example, these teeth are called inner laterals. Each lateral tooth has cusps and together they always occur in a cusp pattern. At the same time, the Sea Otter is the largest member of its family, the mustelids, which includes River Otters, weasels, badgers, wolverines and martens.
It may come to land to flee from predators if needed, but the rest of its time is spent in the ocean. It varies in colour from rust to black.
Unlike seals and sea lions, the Sea Otter has little body fat to help it survive in the cold ocean water. Instead, it has both guard hairs and a warm undercoat that trap bubbles of air to help insulate it. The otter is often seen at the surface grooming; in fact, it is pushing air to the roots of its fur. Mollusks are invertebrates, meaning they have no bones. They are cold-blooded, like all invertebrates, and have blue, copper-based blood. The octopus is soft-bodied, but it has a very small shell made of two plates in its head and a powerful, parrot-like beak.
The Giant Pacific Octopus is the largest species of octopus in the world. Specimens have weighed as much as kg and measured 9. Studies determined, though, that they are indeed different. While the Western Chorus Frog might have slightly shorter legs than the Boreal Chorus Frog, and that their respective calls have different structures, genetics have proven this.
Chorus Frogs are about the size of large grape, about 2. They are pear-shaped, with a large body compared to their pointed snout. Their smooth although a bit granular skin varies in colour from green-grey to brownish.
They are two of our smallest frogs, but best ways to tell them apart from other frogs is by the three dark stripes down their backs, which can be broken into blotches, by their white upper lip, and by the dark line that runs through each eye.
Their belly is generally yellow-white to light green. Males are slightly smaller than females, but the surest way to tell sexes apart is by the fact that only males call and can inflate their yellow vocal sacs. Adults tend to live only for one year, but some have lived as many as three years. Their tadpoles the life stage between the egg and the adult are grey or brown. Their body is round with a clear tail. The Common Raven Corvus corax is one of the heaviest passerine birds and the largest of all the songbirds.
It is easily recognizable because of its size between 54 and 67 centimetres long, with a wingspan of to cm, and weighing between 0. It has a ruff of feathers on the throat, which are called 'hackles', and a wide, robust bill.
When in flight, it has a wedge-shaped tail, with longer feathers in the middle. While females may be a bit smaller, both sexes are very similar. The size of an adult raven may also vary according to its habitat, as subspecies from colder areas are often larger. A raven may live up to 21 years in the wild, making it one of the species with the longest lifespan in all passerine birds.
Both birds are from the same genus order of passerine birds, corvid family —like jays, magpies and nutcrackers, Corvus genus and have a similar colouring. But the American Crow is smaller with a wingspan of about 75 cm and has a fan-shaped tail when in flight with no longer feathers. Their cries are different: the raven produces a low croaking sound, while the crow has a higher pitched cawing cry.
While adult ravens tend to live alone or in pairs, crows are more often observed in larger groups. The Atlantic Cod Gadus morhua is a medium to large saltwater fish: generally averaging two to three kilograms in weight and about 65 to centimetres in length, the largest cod on record weighed about kg and was more than cm long! Individuals living closer to shore tend to be smaller than their offshore relatives, but male and female cod are not different in size, wherever they live.
The Atlantic Cod shares some of its physical features with the two other species of its genus, or group of species, named Gadus. The Pacific Cod and Alaska Pollock also have three rounded dorsal fins and two anal fins. They also have small pelvic fins right under their gills, and barbels or whiskers on their chins. Both Pacific and Atlantic Cod have a white line on each side of their bodies from the gills to their tails, or pectoral fins. This is followed by a second mating cycle, after which she gives birth to a new litter.
The ability to produce a second litter in a season if the first litter is lost is seen in other chipmunk species like the Least chipmunk. So, when do chipmunks have babies?
Anytime between February and August is possible depending upon which of the 25 species of chipmunks are involved. Home Squirrel Facts! Chipmunk Facts! Bat Facts! Birding Foxes Privacy Policy.
California Chipmunk Breeding Cycle The California chipmunk , found in the mountains of southern California, offers more complexity to the baby making equation. Sonoma Chipmunk Breeding Cycle The Sonoma chipmunk , found in northwest California, is an interesting example of another variable in the chipmunk baby equation.
Red-tailed Chipmunk Breeding Cycle The Red-tailed chipmunk , found in the central Rocky Mountains, adds another piece to the baby puzzle. To Sum It Up So, when do chipmunks have babies? If the weather stays warm enough in early fall, some eastern chipmunks mate a second time, then go into semi-hibernation during the winter months. The West Virginia Division of Natural Resources reports females can begin breeding less than one year after they're born.
If born in the summer, most will breed for the first time during the spring of the following year. A few begin breeding as early as three months after their own birth. When mating season begins, according to West Virginia's Division of Natural Resources, several males compete for a female, who makes a chipping sound to signal her readiness to mate. The mating call is the reason chipmunks got their name. The gestation period for both western and eastern chipmunks lasts 31 days.
When the baby chipmunks first come out of their den, they explore the ground near the entrance. At first they are unafraid, but after a few days above ground they are more wary and escape quickly if disturbed. Their mothers keep a close watch on them.
The young grow rapidly during the late summer and reach adult size before the end of September. The mothers and the babies remain together for about three months and then begin to separate. Most breed in their first spring, but some may wait until their second year.
The time of separation is difficult for the young chipmunks. The young must quickly find new homes. Most of the young try to find empty burrows close to where they were born. The other chipmunks in the area make a chip-chip-chip sound. This lets the young know which areas or territories are already taken. Some of the young must travel to new areas to locate a home. Like most small rodents, this chipmunk is subjected to heavy predation. In the boreal forest it is hunted by hawks, owls, ermine, mink, marten and fishers.
In suburban environments, it often falls prey to cats and dogs and a fair number are killed by automobiles. Despite these many enemies, there are not enough of these tiny rodents for any predator to depend on a steady diet of chipmunk. It makes more sense for a predator to specialize in mice, which are more abundant and more easily caught. However, its numbers are high. A female will produce a litter of 2 to 7 offspring each year.
Chipmunk numbers usually do not vary much from year to year, but local declines and disappearances have been recorded. These declines have never been satisfactorily explained. Chipmunks can be seriously wounded when they compete among themselves or with large animals such as red squirrels for food and space.
In addition, some may die as a result of wounds received in fights during the breeding season. Males fight among themselves when competing for females, and females have been observed defending their nests and young against other chipmunks.
Disease and food shortage may also limit chipmunk populations but, once again, little is known about these factors. Seed crop failures are likely to have a significant detrimental effect on chipmunks, which depend on stored food to survive the winter.
Disease epidemics have not been reported from chipmunks, but are known to occur in populations of mice and other rodents.
Parasites, such as botfly larvae, tapeworms, fleas, mites, and probably lice, can have a debilitating effect and, on rare occasions, even cause death. In the wild, the chipmunk's life span is from two to five years. Chipmunks are important in the dispersal of seeds because of their habit of storing them beneath the layer of decaying vegetation on the forest floor. Any buried seeds that are not consumed stand a better chance of germinating than those remaining on the surface litter.
In this way, chipmunks assist in the spread of shrubs, trees, and other plants. If chipmunks are very abundant, they can prevent normal reforestation of some trees, especially pines, by eating their seeds. Occasionally chipmunks and other rodents are trapped to ensure adequate germination and growth of seedlings. Poisoning is not an acceptable means of control because of the harmful effects on other wildlife including gamebirds and songbirds. Much of the value of chipmunks lies in the pleasure they provide for campers, hikers, and anyone who enjoys the country.
Our national and provincial parks and our summer cottages and trailers would be less interesting and less enjoyable without chipmunks dashing across forest trails or boldly helping themselves to food in campgrounds and picnic areas. Twenty-one chipmunk species occur in North America, including one in eastern Canada and four in western Canada. All these species belong to the genus Tamias, which is divided into two main groups. The first subgenus, also called Tamias, contains the eastern chipmunk T.
It also contains the only species of chipmunk from outside North America, T. The other subgenus, Neotamias, contains 20 species, all of which are native to western North America. Four Neotamias species are found in western Canada. The least chipmunk T. Chipmunks are so light that their prints rarely show details.
Forefoot has four toes, hind foot has five. These chipmunks run on their toes, therfore the forefoot pads do not show, the hind feet have no pads. Hind prints register ahead of the fore prints and tracks are erratic. Trails usually lead to a burrow.
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