March Bird Group meeting report— Northern Bobwhite and Gray Partridge
Our regular Meeting was held on the 2nd Wed of March at Martin Chen’s home. A good turnout enjoyed the light refreshments while chatting before getting down to the business of discussing the two birds for the evening.
Our first bird was the Northern Bobwhite (Colinus Virgianus), a bird of Eastern North American which uses a variety of habitats in different parts of its range. It is also extremely variable in plumage, both within and between the 20+ subspecies (see below). It is a bird which is also raised in significant numbers for hunting, even as its overall numbers decrease in parts of its previous range, due to such things as land-use changes, pesticides, and (in Mexico) overgrazing. Some 20 million birds are shot annually.
In Ontario it used to be fairly widespread, but at present the only native breeding birds seem to be found on Walpole Island, although escaped and released birds can be occasionally found in SW Ontario.
The diet is also quite flexible, depending on the habitat — in farmlands it will go for the dominant seed crop, in Mexico both the seeds of various native plants, and those of cultivated crops. Insects and small invertebrates are important in Summer (especially for new young). Commercial growers have made use of a variety of feeds as well.
Breeding is from early to late Spring, depending on location. Hens usually lay from 12-20 (10-30) eggs in a shallow depression in the ground which is lined with dead vegetation (usually hidden from above). The male may begin calling with its loud and unmistakable “bob-bob-white” call in March, but nesting is later. The adults and young from several nests will gather after breeding into coveys of 20-30 birds, which generally remain hidden unless flushed.
This bird ranges from 130-170 g in weight, 20-25 cm in length, increasing in size from the southern portions of its range to the North.
Here are some typical images (M and F):
Our second bird was the Gray Partridge. This is another bird which can be found in Ontario, although only in a couple of areas for the most part. It is a widespread native in much of central Europe, but has also been introduced in many spots around the world, including Canada and the USA. In Canada it was mainly introduced in the early 1900’s, and is now widespread where suitable habitat is found. It used to be quite widespread in Ontario, but in the last atlas its area had declined markedly, especially in SW Ontario, and it is principally found in the NE part of the Province. Causes of decline here (and worldwide) are probably related to changes in agricultural practices, especially reduction of edge habitat and increases in pesticide use in Spring.
The bird is very variable in plumage, and is generally 29-31 cm in length, 310-455 g in weight. The males tend to bland gray with a rufous neck, and a dark belly patch. They have a distinctive habit of flicking the tail open to show orange-rufous outer feathers. The female is plain gray-brown overall, with cinnamon bars and pale streaks on the flanks running toward the belly. Some typical birds are shown below.
It tends to prefer open grasslands or farm fields, and to make its nest in edge spaces. It is very hard to see in the grass, and tends to walk rather than fly (they do not migrate). The males call with a metallic “kee-uck” in early Spring. They are easier to find in Winter, when their covey’s may show up in snow-covered fields.
Their diet is mostly seeds (many varieties), also leaves (green leaves of grasses in Fall), and insects. Young are dependent on insects for the first couple of weeks.
They tend to pair up in early Spring, nesting late Spring (earlier in South, later in North). Normally monogamous, but occasionally male with two females for up to two weeks. They will renest later. After chicks are grown, pairs break up and join coveys. Nest is typically a shallow depressionleined with leaves and grass, at base of hedge or some similar heavy vegetation. First cluteh typically 15-17 (4-24) eggs, fewer in second nesting; incubation 23-25 days, usually by female alone. Downy chicks have rufous, chestnut and black markings on buff upper parts, creamy6 yellow underparts. They are capable of precocial flight after roughly 2 weeks. They achieve full weight at roughly 100 days. Chick survival to 6 weeks is very variable, as they are vulnerable to many ground predators. The are capable of precocial flight after roughly 2 weeks, and achieve sexual maturity in first year.
Here are some typical birds: