Grant: Discovery Grants Program - Individual

) Feeding breadth in aggressive tree-killing bark beetles has implications to outbreak initiation and duration. An outbreak of mountain pine beetle in western Canada currently covers an area approaching 10 million ha. While the primary host of mountain pine beetle is lodgepole pine, its recent progression into Alberta has raised the prospect of expansion into jack pine of the boreal forest that stretches to the Maritimes. In the interior of British Columbia, a shrinking supply of mature lodgepole pine has led to increased attacks on young lodgepole pine and mature spruce. While phloem in young pine is generally too thin for viable brood development, little is known about potential development in mature spruce. Preliminary studies in spruce indicate that brood development may be as successful as in mature lodgepole pine. Such development, in concert with potential host fidelity (i.e., the propensity of progeny to reattack similar host species) could lead to host race formation, and, pending barriers to gene flow such as developmental asynchrony in different hosts, specialization. The proposed research seeks to study potential costs and benefits to reproduction in a ""novel"" host in an aggressive, tree-killing bark beetle as a possible step in host-race formation and feeding specialization.