Here are some basic things to know. There are three species of swans in North America. The Mute Swan Cygnus olor is a Eurasian species that has been introduced and now breeds in the wild in some areas. All three are very large all-white birds. Trumpeters and Tundras are similar looking species that are often difficult to tell apart.
Distinguishing Trumpeters from Tundras is not easy, but it is possible by paying close attention to a few distinctive characteristics. Mute Swans are easily identified by the bright orange bill and distinctive knob on the forehead. Trumpeter Swan head profile with straight black bill and "lipstick red" mandible. Photograph by Richard Sonnen. The male swan is called the Cob.
He typically weighs more and looks slightly larger than the female the Pen , although it is often difficult to tell the male and female apart. The cygnets, or young, feed predominately on insects and other invertebrates for the first few weeks of life but may start feeding on plants before they are two weeks old. On their wintering grounds in coastal British Columbia, the birds eat primarily roots and tubers of emergent plants, or plants rooted in the water but with most of the growth above the water, on tidal flats.
The swans prefer to feed in a shallow covering of water, as the tide floods or recedes. They are pumped up and down over edible roots to create a current of water that frees the roots from the surrounding mud. They also help the bird to maintain its balance when it tips up to feed.
Many of the ponds where they breed are still frozen when they arrive, but some of the larger bodies of water may have open leads, where the swans congregate. Young from previous seasons usually gather in small flocks, remaining together throughout the summer on lakes not occupied by breeding pairs.
Breeding birds select nest sites that are surrounded by water from 10 cm to several metres in depth. They frequently construct their nests on old beaver houses and dams, but they also build on emergent vegetation, either floating or anchored to the bottom. Pairs often begin to build or repair their nest even before a site is completely free of ice. Most nests are used year after year, usually by the same pair. Rebuilding does not usually involve much more than adding plant material to an already substantial mound.
The female, or pen, lays one egg about every two days, until she has produced an average of five or six eggs, or occasionally up to nine. She incubates, or keeps the eggs warm, for 32 days until they hatch while the cob helps to defend the nest from predators and intruders. The peak of the hatching period in the Grande Prairie region is about June 15; in the Yukon and Northwest Territories it is nearer July 1. The cygnets emerge covered in a dense pale grey down and remain in the nest with the pen for at least 24 hours, until they are able to maintain their own body temperature.
The adults moult, or shed, their feathers in summer and are flightless for a month or more. The pen usually loses some of her flight feathers about the time her cygnets hatch and is flightless during their most critical period.
The cob becomes flightless about the time the pen regains her flight. In this way, one flightless parent remains with the cygnets during the brood period. The cygnets grow from approximately g at hatching to approximately 7 kg at fledging, or first flight. Feathers first start to appear at about 28 days, and the cygnets are usually fully feathered in nine or 10 weeks. They start to fly in the second half of September in the Grande Prairie area, and in early October in the Northwest Territories.
Trumpeter Swans have survived in captivity for up to 35 years, but in the wild most swans live for less than 12 years. Upon their arrival, Europeans hunted and harassed the swan to the point where in there were only 77 Trumpeters breeding in Canada and 50 breeding in the United States.
Today, as a result of an intensive international conservation effort, there are about 16 wild Trumpeter Swans, and the species is no longer considered in danger of extinction. Except for people, wild Trumpeters have few natural enemies. Eagles, owls, coyotes, and mink may take swans at certain times but these instances are infrequent and usually affect very young birds or adult birds that have become weakened and unable to fend off predators.
Diseases and parasites, alone or combined with bad weather or local food shortages, may also result in some deaths. The most serious threat to the continued well-being of the Trumpeter Swan is the loss of habitat resulting from expanding human populations. People are also responsible for accidental deaths, although it is rare for these to have a serious effect on populations, except perhaps on a local scale.
The Pacific Coast Population is currently increasing and expanding its range, especially within its Alaskan breeding areas. The settling of Alaska may prove to be as detrimental to Trumpeter Swans as was the settlement of the plains.
This population is vulnerable to catastrophic losses from disease, habitat destruction, or exceptionally cold weather while the birds are concentrated on their Tri-State where the states of Idaho, Montana, and Wyoming meet wintering grounds. Any long-term expansion of this population probably depends on the enhancement of existing wintering habitat and the creation of new wintering traditions. The first official management action that was and still is of great benefit to the Trumpeter Swan population was the inclusion of swans as protected species under the Migratory Birds Convention of These have included winter feeding programs, special sanctuaries and reintroduction programs, population surveys, and federal, provincial, and state land-use guidelines.
The North American Management Plan for Trumpeter Swans calls for the continuation of these actions and outlines many others that are needed to ensure the continued survival and growth of the Trumpeter Swan population.
Although the total population of Trumpeter Swans is still small compared with what it once was, such management efforts, combined with habitat protection and enhancement, and reintroduction programs, should ensure that numbers of this magnificent bird will continue to rise and that it will once again inhabit much of its former range. All About Birds, Trumpeter Swan. Audubon Field Guide, Trumpeter Swan. Ducks Unlimited Canada, Trumpeter Swan. Banko, W. The Trumpeter Swan.
North American Fauna No. Fish and Wildlife Service, Washington. All rights reserved. McKelvey Revision: L. Shandruk, Photo: Tom W. 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. Spring migration begins early, birds often reaching nesting territory before waters are free of ice. The same climate change-driven threats that put birds at risk will affect other wildlife and people, too.
Hover over or tap an area on the map to see specific threats that will affect that area. A recent 5K art run introduced people to birds and the threats they face due to climate change. Can he save this heron rookery before it's too late? Latin: Cygnus columbianus. Latin: Cygnus cygnus. Latin: Cygnus olor. Membership benefits include one year of Audubon magazine and the latest on birds and their habitats.
Your support helps secure a future for birds at risk. Our email newsletter shares the latest programs and initiatives. Largest of the native waterfowl in North America, and one of our heaviest flying birds, the Trumpeter Swan was almost driven to extinction early in the 20th century.
Its healthy comeback is considered a success story for conservationists. Ordinarily the Trumpeter is quite sensitive to human disturbance; in protected areas, such as some parks and refuges, it may become accustomed to humans and allow close approach. Photo gallery. They winter in coastal lakes and rivers from southern Alaska and western British Columbia southward into the United States, to Oregon, Nevada and Wyoming, but also as far east as the state of New York.
Looking for photos? The Canadian Museum of Nature has thousands of unique images reflecting the diversity of the natural world—including the photos and illustrations here in our Natural History Notebooks. Contact us to learn more! Natural History Notebooks. Canadian Museum of Nature. Last updated Web site consulted.
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