A land manager's guide to conserving habitat for forest birds in ...

Logging gap — Photo: Teresa Piraino
11. Manage high deer populations
The sight of a white-tailed deer stops most people in their
tracks. Even to the most seasoned rural resident, deer are
beautiful, interesting, and graceful creatures that represent the
wild. In some parts of southern Ontario, high white-tailed deer
populations are a big problem. Even to the untrained eye, the
absence of plants at lower levels and a razor-straight browse line
(the maximum height at which deer feed) is an obvious sign of
high deer populations. Deer browse on trees and shrubs for food
and can reduce understorey vegetation and limit tree seedling
regeneration. A forest that is over-browsed is open and park like
with an unobstructed view of distant tree trunks, inedible
plants, and hardy exotics. Excess numbers of deer render an
ecosystem’s ability to regenerate virtually impossible.
Wildflowers, native shrubs, and tree seedlings have vanished.
Without the herbaceous (flowers, grasses, ferns, etc.) and woody
plants in the forest’s lower layers, many birds and wildlife are
adversely affected. If your woodland has high deer densities you
could consider installing deer fencing (page wire or electrical) or
allowing deer hunting to reduce deer numbers and provide an
opportunity for your forest vegetation to recover.
White-tailed deer — Photo: Larry Watkins
12. Manage forest edges, fragment
size, and connectivity
Though diversity of plants and animals
typically increases proportionately with the
amount of edge in a stand, these edge species
tend to be habitat generalists. Hard edges, in
particular, such as those between a woodlot
and a cultivated field can be hostile places
for many forest specialists. Various factors
control edge effects, including forest size,
forest shape, surrounding vegetation contrast
(hard vs. soft edges), edge orientation, and
species specific responses. You can moderate
edge effects by a variety of practices,
particularly increasing patch size and
managing for compact (square or circular)
shaped fragments. Small stands, irregularly
shaped, and long, narrow stands with high
edge exposure are most vulnerable to outside
disturbances. We believe edges are
detrimental to some birds because of
reduced reproductive success and increased
rates of nest parasitism and predation,
particularly within 50 m of a forest edge.
Allowing forests to naturally seed into
Naturally seeded field adjacent to forest — Photo: Teresa Piraino
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Guidelines for Forest Management and Maintenance of Forest Bird Diversity