Trumpeters have all black bills; Tundra Swans, formerly called Whistling Swans, have more sloping bills, usually with a small yellow patch in front of the eye. If this patch is missing, it is quite difficult to distinguish between the two birds unless the voice is heard. At close range, an observer should look for a salmon-red line on the lower bill. A third type of swan, the Eurasian Mute Swan, is often seen in Canadian parks and zoos.
The Mute is all white with a black knob on a reddish-orange and black bill. The Trumpeter Swan is the largest of the three species. Signs and sounds Although very similar in appearance, the Trumpeter Swan and the Tundra Swan have quite different voices. The Trumpeter Swan has a deep, resonant, brassy, trumpet-like voice; the voice of the Tundra Swan is softer and more melodious.
During the early part of the winter, when the weather is mild and wet, the swans may be widely dispersed, feeding in freshwater and estuarine wetlands and flooded farm fields along the coast.
When the freshwater areas freeze, the swans congregate on the estuaries, which do not freeze because of the combined influence of tides and salt water. The two dominant activities of Trumpeters on the wintering grounds are feeding and resting.
On the British Columbia coast, feeding is strongly influenced by cycling of tides in the estuaries. The birds feed at times during the day and night when the preferred amount of water covers their plant food. In some parts of the winter range, such as Vancouver Island, more of each hour period is spent resting than feeding, probably thanks to relatively mild temperatures and the availability of foods rich in carbohydrates, which provide ample heat energy.
Unique characteristics Trumpeter Swans are well adapted for the harsh environments in which they sometimes live. Their unusually dense layer of down, which can be up to 5 cm thick, seems to make them almost impervious to the cold. Lawrence River. Large wintering populations were known from the central Atlantic coast of the United States, the Gulf of Mexico, the Ohio and Mississippi river valleys, and parts of the west coast. Heavy hunting by European settlers, for their own use and for the swan skin trade, and possibly habitat changes associated with settlement, combined to eliminate the Trumpeter from all but a small portion of its range.
Two of these populations developed primarily from remnant flocks that survived the historic decline. The third consists of flocks that have been created by transplanting wild birds from established flocks into promising habitat and by breeding swans in captivity and releasing the young to the wild. There are over 1 Trumpeter Swans held in zoos and by private aviculturists, or bird breeders, worldwide. Trumpeter Swans are found in Canada year round.
Birds from the Rocky Mountain Population are in Canada only in the summer, whereas birds from the Pacific Coast Population winter in British Columbia, after spending the summer in Alaska. Trumpeter Swans leave the Grande Prairie region of Alberta, Yukon, and the Northwest Territories in late October, when freeze-up is well advanced, for their journey south to the area where the states of Idaho, Montana, and Wyoming meet Tri-State area.
In the Tri-State area, geothermal activity, such as geysers and hotsprings, warms ponds, rivers, and streams. In addition, fast currents make it possible for small portions of rivers to stay open even under the coldest of temperatures. The Rocky Mountain Population depends on this open water and on supplemental feeding to survive the winter in the area.
Trumpeters from Alaska begin arriving along the British Columbia coast about November 1. Peak numbers are generally not seen until January or early February. Spring migration for the Pacific Coast Population begins in mid- to late February, depending on the weather. By mid-March most Trumpeters have disappeared from the coast, not to appear on the Alaskan breeding grounds until mid- to late April.
After the swans leave the estuaries, they cross the Coast Mountains. Once east of the mountains they fly north, stopping at various large lakes in central British Columbia and southern Yukon on the way. During summer, Trumpeters feed on leaves, tubers, and roots of aquatic plants at depths up to 1 m, which they reach by dipping their heads and necks, or by up-ending. 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. Females lay 4 to 6 eggs, and will keep the eggs warm for 32 to 37 days until the eggs hatch. Baby swans are called "cygnets. They fledge are able to fly and leave the nest after 91 to days but will stay near their parents until they are about a year old.
Both parents participate in nest building which lasts 2 to 5 weeks. The female will perform most of the egg incubation until the young hatch. Unlike most birds, trumpeter swans do not cover the eggs with their stomachs, but instead use their feet to keep the eggs warm. The young are born precocial, meaning they have downy feathers and eyes are almost open. Cygnets are ready to leave the nest within a few days of hatching, but will remain with their parents who care for them through their first year.
The oldest captive trumpeter swan on record was 33 years old. In the wild, the oldest known individual was Krementz, et al. Trumpeter swans live in small flocks, often with members of their own family. Their daily routine varies from season to season. In winter they rest more and eat less, while in spring they consume large amounts of food and are very active during the day. Flock size also varies seasonally. In spring, flock size can be almost half than found in the fall because the young have left and the breeding season is about to begin.
Trumpeters are known to be very territorial during the mating season. They can become incredibly violent towards competitors, other swans, or any animals that could pose as a threat that invades their space. Trumpeters are migratory birds. When the weather gets colder mid-October to late November they begin a slow migration, with the first stop usually at Yellowstone National Park, and other parts of Wyoming and also parts of North Dakota.
They remain there until the water freezes over and then they move onto scattered places including Utah and Arizona where the winter climate is much warmer. Many trumpeter swans spend the winter on the western coast of Canada, Alaska, and Washington. Earnst, ; Slater, Trumpeter swans are very territorial and rarely leave their nests unguarded. Their nests are built on or near aquatic vegetation, and the adults do not need to wander far from the nest for food. Thus, the home range during the breeding season, though not calculated, is not expected to be substantial.
Trumpeter swans produce a variety of sounds, but they are known for their low bugle call. In addition to the bugle call, they also use motions such as head bobbing to alert others of disturbances or in preparation for flight. Trumpeter swans call to warn the flock of impending danger. Trumpeter swans are very social creatures except for in times of mating, when they become quite territorial.
Breeding pairs perform visual displays together which likely reinforce the pair-bond. Young cygnets eat mostly aquatic insects. At five weeks of age, most cygnets have converted to a nearly herbivorous diet. This diet consists of tubers, roots, stems, and leaves aquatic vegetation as well as occasional insects. In Alaska during mating season, the wetland plants commonly known as horsetail and Lyngbye's sedge are consumed in great quantities.
However, because of the wide distribution of the species there are some variations of their diet such as duck potato, water weeds, pondweeds and sago pondweed tubers. Trumpeter swans attain their food by foraging underwater with their heads underwater and tails bobbing in the air. They also yank plants out of the damp ground, with most of the plant intact.
Although adults aggressively defend their nests, ground nests are easy targets for land predators. Many predators, such as bears , wolves and coyotes , wolverines , raccoons , and common ravens are known to snatch eggs. Young cygnets and adults are prey to fast predators such as coyotes , bobcats , red foxes , and golden eagles. The main predator of adult trumpeter swans is mankind. Humans have hunted more of these swans than anything else. Trumpeter swans are aggressive towards predators, and at 12 kg with a 2 m wingspan, they can potentially inflict serious damage.
Trumpeter swans do exhibit warning behaviors before they attack, including head bobbing and hissing. Kraft, ; Schmidt, et al. Trumpeter swans' main role in the ecosystem is linked to their diet. Trumpeter swans eat many insects when they are young, but as they grow they switch to roots and aquatic plants. Swans use their beaks to dig around plant roots and will yank up whole plants from the ground.
These holes in the ground allow for water and other nutrients to enter the soil and nourish the remaining organisms. Trumpeter swans can also be a host to parasites including tapeworms, trematodes, and heart worms. But my photos show body and bill shape, and also reveal that a couple of the birds appear to be molting their outer primaries.
Does this observation provide a clue to identification, based on the differences in timing of molt that you mention? You can see a few of the best photos in the links below. Any thoughts you can share about these birds would be most appreciated. Thanks for the distinction between the two. We are seeing the most Trumpeter swans ever this year. The population seems like it has greatly increased in the past yrs.
I have seen an occasional pair with babies on the Gull River in the summer, then they switch to the lake just before the ice fills in. There are at least Some juveniles. I think all Trumpeters. Tainter Lake WI, We have had several recent opportunities to observe both together. Trumpeters are larger longer in the body , slower in the water—we have not seen them yet on land—and show more curvature to the neck.
Trumpeter plumage upon observation a bit more white-white, but this may not hold—our lake water is pale brown from pine needles.
Best regards all! I assumed I would be able to listen to some recordings to tell which species they were, so I went inside immediately and listened to my Stokes CDs, only to find that nothing resembling the call I heard is included in the recordings of either species.
So I switched to the Internet and listened to calls of both species, from numerous sources, with the same result.
There are no recordings of the flight call I heard, or anything really close to it. I heard the birds in mid-flight rather than taking off. Perhaps this sound is not included in any of the recordings because it is not regarded as diagnostic.
Any help would be appreciated. Good to hear they are growing in number. For the first time ever, I observed a flock of eight swans on our reservoir here in Upstate South Carolina Oconee County. This was my first time seeing swans, which I believe to be Tundra swans. They flew away in formation much like Canada geese, although not as noisily. This is late migrants either case, they seemed alert in field though not very wary of me stopping my vehicle and getting out on the road to snap a couple photos.
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