![]() #Bird expert clipart seriesThis bird came from either the eastern Siberian breeding population or the European breeding population and, through some unusual series of events, came to find a temporary home in B.C. For example, a Eurasian thrush called a Fieldfare ( Turdus pilaris) occurred in Port Coquitlam in B.C.’s Lower Mainland in December of 2003. These individuals, called “vagrants” or “accidentals,” can show up hundreds to thousands of kilometers away from their normal range. ![]() The power of flight, combined with the long distances that many bird species traverse between their breeding and wintering grounds, results in many birds occurring in areas outside of their normal haunts every year. Stellar's Jay, BC's official bird, photo by Rod Innes ![]() ![]() when compared against other jurisdictions. Comparison of the number of bird species recorded in each of Canada’s provinces and territories, illustrating the relatively high number of species for B.C. Of the 510 species recorded from B.C., more than 310 are known to breed or have bred in the province and several others are suspected of breeding. No other jurisdiction in Canada can boast such a diverse assemblage of habitats as B.C. These habitats include marine and pelagic environments, coastal rainforests, dry grasslands and sagebrush, freshwater lakes and wetlands, montane and boreal forests, alpine tundra, agricultural lands, and urban areas. This wealth of birds is due to the province’s location at the junction of several major biogeographic units (Great Basin, western cordilleran, eastern boreal, Pacific coastal, subarctic, etc.) as well as the wide range of habitats that occur. The advent of advanced genetic techniques for determining relatedness of species, such as DNA-DNA hybridization, will continue to challenge some of the taxonomic dogma of the 19th and 20th centuries and, hopefully, result in a clearer picture of the evolution and classification of birds in years to come.Ī total of 510 species of birds (65 families) are known to have occurred in British Columbia over the past 150 years, which is more than any other province or territory in Canada (Table 1). Photo by Diane Williamson.Ī total of 26 orders, 225+ families, and 9,800-10,000+ species of living birds are currently recognized within Class Aves, although there is much flux in these number and some additional orders, families, and (especially) species are often recognized. Other diagnostic features of birds include the laying of hard-shelled eggs, the modification of the front two limbs into wings (even on species which are incapable of flight), a beak with no teeth, a high metabolic rate, and a four-chambered heart (similar to mammals).Ĭedar Waxwing, tail feathers. Furthermore, flight would not be possible in birds without feathers, particularly feathers on the wings and tail known as “flight feathers.” Another characteristic feature of birds is a largely hollow skeleton that dramatically reduces the weight of the bird and increases the efficiency of flight. ![]() First, the presence of feathers is unique to birds and allows for increased thermal regulation. They are considered, along with crocodilians and the dinosaurs themselves, to constitute the reptile clade Archosauria, illustrating the surprisingly close relationship of birds to both dinosaurs as well as modern reptiles.īirds are characterized by a number of features, many of which are designed to facilitate flight. Birds originally evolved from therapod (beast-footed) dinosaurs during the Jurassic period (150-200 million years ago). Photo by Ted Ardley.īirds are classified as the biological class Aves, which encompasses all living species of birds as well as all extinct species that have occurred since Archaeopteryx lithographica(the earliest recognized species of bird). ![]()
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