3. A species of woodpecker inhabits a reserve adjacent to a suburban housing development. The species
nests in cavities that it excavates in large trees, and
rarely crosses roads or areas that do not provide at
least some vegetative cover. The population inside
the reserve is small and relatively isolated from other
larger populations in the region.
(a) Describe ONE density-dependent and ONE
density-independent factor that could affect the
woodpecker population in the reserve. (2 points)
(b) Describe TWO potential problems with the
isolation and lack of gene flow the population
experiences due to the housing development.
(2 points)
(c) The particular species of woodpecker is an
r-selected species. Explain what this is, including
THREE typical characteristics of an r-selected
species. (4 points)
(d) After creating and nesting in a tree cavity, the
woodpeckers abandon the cavity, allowing it to
be used by several other species of cavity-nesting
birds that are unable to excavate their own cav-
ities. Based on this description, identify the role
the woodpecker species plays in its ecosystem.
(2 points)