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Image Credits: photo by Steve R. Cannings The Yellow-breasted Chat, a member of the family Emberizidae, is about 18 cm in length (very large for a warbler) with a bright yellow throat and breast and white "spectacles". The two subspecies found in Canada can be distinguished by their appearance. The Western Chat, Icteria virens auricollis, has more greyish upper parts, the white of the malar region in more extended, the yellow of the under parts is deeper, and the wings, tail, and bill are longer than those of the eastern subspecies, Icteria virens virens. The Yellow-breasted Chat is a bird more often heard than seen since it is usually hidden in brushy riparian tangles or hillside thickets. Its loud whistles, chatters and squawks make it easy to identify. It will often sing at night, and the voice is the lowest-pitched of any of the American wood warblers. Besides being much larger than other wood warblers, it also has strikingly unwarbler-like characteristics such as: holding its food with its foot; having a unique song and aerial courtship displays; developing no natal down; and being the only warbler that has a complete post-juvenile moult . The bird that breeds in the Thompson-Okanagan region has a couple of common names. Formerly known as the Long-tailed Chat, it is now referred to as the Western Yellow-breasted Chat (Icteria virens auricollis).
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British Columbia
North America However, despite being the same subspecies as the one on the prairies, the population in British Columbia occupies a separate biogeographic area, and consequently, it is treated separately for the purpose of assigning status designations. The Ontario population is also treated separately, since it is a separate subspecies from the western population. In the United States, the Eastern Chat breeds from North Dakota, southern Minnesota, southern Wisconsin, southern Michigan, central New York, southern Vermont and southern New Hampshire south to south-central Baja California, Jalisco, the state of Mexico, southern Tamaulipas, the Gulf states and northern Florida and winter from Mexico and southern Texas south to western Panama. The Yellow-breasted Chat is a bird of edges of woods, fencerows, dense thickets and brambles in low wet places near streams, pond edges, or swamps and in old overgrown clearings and fields. It also nests in small trees such as trembling aspen, saplings or bushy tangles, favouring wild rose, hawthorn and snowberry thickets. Other shrub species commonly used, include elderberry and saskatoon bushes. What appears to be important for good chat habitat are areas of essentially impenetrable thickets with few small trees; it is not a bird of older forests or woodlands. In fact, it often is typically associated with the early successional stages of forest regeneration, living close to human habitation. The Yellow-breasted Chat habitat is protected in the Vaseux-Bighorn National Wildlife Area, Inkaneep Provincial Park, and the Osoyoos Oxbows Wildlife Management Area. A significant number of territories, however, are located on Indian Reserves, some of which are presently undergoing intense development in British Columbia. Although no data are readily available, the amount of suitable habitat for chats in British Columbia has almost surely declined considerably in this century. The lowland riparian thickets favoured by chats are very vulnerable to clearing for agricultural and residential/industrial developments. There now seem to be only five sites remaining in the province that are suitable for breeding: the south Similkameen Valley, which probably contains the most extensive habitat in the province; Okanagan River oxbows at north end of Osoyoos Lake; Okanagan River between Inkaneep Provincial Park and McIntyre Bluff; Vaseux Lake, primarily at the north end but previously at the south end, as well; and woodlands along the Okanagan River on the Penticton Indian Reserve. Chat territories next to farmlands, particularly orchards, might be affected by pesticide applications either indirectly (through loss of insect food) or directly (through direct contact with pesticides). There are no data on either of these possible problems. Brown-headed Cowbird parasitism occurred in 3 of 14 chat nests found in the Okanagan Valley during one study. Chats may be relatively unaffected by cowbirds however, because they can apparently successfully raise most of their own as well as the cowbird young. Because chats are secretive and shy, nest sites are often difficult to approach; thus direct human disturbance is apparently not a threat. However, indirect disturbance, primarily in the form of habitat destruction, may be a serious threat to the species. The Yellow-breasted Chat's normal behaviour does not expose it to danger, and it is not susceptible to special conditions such as fire, fluctuating water levels, severe winters, or wet or dry seasons, but it is susceptible to cold spells or other conditions that affect insect populations.
Breeding The nests are large and bulky, but well-concealed. Cup-shaped nests composed of coarse materials like leaves, shreds of bark, coarse straws and weed stalks and lined with fine grasses are located low in dense bushes, usually not more than a metre from the ground. Frequently, the nest is impossible to investigate (or locate) due to its frequent placement in thick thorn scrub and dense thickets. Since only thirteen chat nests have been reported from British Columbia, breeding success data are minimal. Hatching success is known for two nests; in both of them one egg of the clutch failed to hatch. Reported fledging brood sizes range from one to two young, so a very rough breeding success rate would be 48%.
Behaviour The Yellow-breasted Chat is usually monogamous. Sometimes they will nest in groups or "colonies" but forms separate territories. A study in Indiana in the late 1960s and early 1970s found that males either formed pair-bonds with a succession of females in one season, remained paired to one female the entire time they were on the study area, or were for a time paired to one female and for a time unpaired; only one male exhibited polygyny. However, nesting success apparently had a profound effect on the stability of the pair bond. Pairs that experienced no nest failure in a particular breeding season remained together throughout the season, about 50% of males that experienced nest failure bred again to new mates. Chats are migratory and usually return to the Okanagan in the third week of May or shortly after. There are a few records after mid-July, when the young birds have fledged; it appears most birds leave by mid-August. The western Yellow-breasted Chat winters from southern Baja California, southern Sinaloa, southern Texas and southern Florida (casually from California, the Great Lakes region, New York and New England) south through Middle America to western Panama (western Bocas del Toro). There is little information regarding the species on its wintering grounds, and it is unknown whether it concentrates in any specific areas during the winter. They leave to return to breeding grounds about the middle of April. Like other small passerine species, the Yellow-breasted Chat matures in one year and generally has a short life span, but the longevity record is eight years, 11 months.
Diet or Growing requirements
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