Dark-eyed Junco (Junco hyemalis) (2)
Dark-eyed Junco looking for seeds on the lawn at our friends cottage on Kenogamissi Lake in the Township of Doyle in Northeastern Ontario Canada
Most (including all northern) populations are migratory. The peaks of migration are in October and March/April. The winter range extends across southern Canada and virtually all of the lower 48 states into northern Mexico. Juncos are found year-round throughout much of the West, Great Lakes region, Northeast, and Appalachians, though these areas experience complete or partial turnover of individuals. Adults, especially females, tend to migrate farther (and begin migration earlier) in eastern populations. For example, winter junco flocks are 20 percent female in Michigan and 72 percent female in Alabama. Western flocks are less segregated due to greater mixing of populations. Some montane populations exhibit altitudinal migration, with age and sex differential mirroring that of latitudinal migration. Female mortality is probably higher than that of males during migration due to the greater distance but lower in winter because of milder weather; thus, net survivorship and sex ratios on the breeding grounds are about equal. Migration is typically at night. Flock composition probably changes from day to day during migration; individuals apparently seek one another out for group foraging and roosting during the day and may depart en masse at night but do not stay together during flight.
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This photograph and all those within my photostream are protected by copyright. They may not be reproduced, copied, transmitted or manipulated without my written permission.
Dark-eyed Junco (Junco hyemalis) (2)
Dark-eyed Junco looking for seeds on the lawn at our friends cottage on Kenogamissi Lake in the Township of Doyle in Northeastern Ontario Canada
Most (including all northern) populations are migratory. The peaks of migration are in October and March/April. The winter range extends across southern Canada and virtually all of the lower 48 states into northern Mexico. Juncos are found year-round throughout much of the West, Great Lakes region, Northeast, and Appalachians, though these areas experience complete or partial turnover of individuals. Adults, especially females, tend to migrate farther (and begin migration earlier) in eastern populations. For example, winter junco flocks are 20 percent female in Michigan and 72 percent female in Alabama. Western flocks are less segregated due to greater mixing of populations. Some montane populations exhibit altitudinal migration, with age and sex differential mirroring that of latitudinal migration. Female mortality is probably higher than that of males during migration due to the greater distance but lower in winter because of milder weather; thus, net survivorship and sex ratios on the breeding grounds are about equal. Migration is typically at night. Flock composition probably changes from day to day during migration; individuals apparently seek one another out for group foraging and roosting during the day and may depart en masse at night but do not stay together during flight.
©Copyright Notice
This photograph and all those within my photostream are protected by copyright. They may not be reproduced, copied, transmitted or manipulated without my written permission.