Marbled Murrelets, seabirds that use large branches of old trees (>140 yr) for nesting platforms in coastal forests, are listed as a threatened species federally (Committee on the Status of Endangered Wildlife in Canada) because of the perceived rate of population reductions from loss of nesting habitat with a lengthy (e.g. 150 yr.) regeneration time. They are managed under the provincial Forest and Range Practices Act (Identified Wildlife Management Strategy Account) and Federal Species at Risk Act (Recovery Plan produced by Canadian Marbled Murrelet Recovery Team (CMMRT)). Habitat management for murrelets currently focuses on maintenance of acceptable quantities and quality of nesting habitat and follows habitat definitions and habitat assessment methods proposed by the CMMRT (2003). The CMMRT (2003) habitat quality ranking is based heavily on
(1) the availability of large tree branches suitable as nesting platforms (more large branches = better habitat), and
(2) structural stand characteristics related to the birds? ease of access to platforms (more complex stands = easier access).
Nesting habitat is currently identified using three filtering methods: airphoto interpretation, helicopter flyovers, and ground sampling. Airphoto interpretation is least costly, helicopter flyovers more costly and ground assessments most costly, but only the latter two methods provide direct measures of platforms. BC protocols are now defined, but untested, for airphoto and helicopter methods.
Our research will:
(A) better define which stand attributes best predict nesting habitat quality for murrelets for each assessment method,
(B) test the relationships and reliability of three methods and multiple attributes currently used to define habitat, and
(C) detail particular habitat relationships to allow more accurate cost/benefit tradeoffs when defining areas of habitat available and selecting particular areas for conservation.
David B. Lank and F. Louise Waterhouse.
Lank, David B., Waterhouse, F. Louise; Donaldson, A.; Ott, Peter K.; Krebs, Elsie A.; Burger, Alan E.; Parker, N.. 2006. Identification of critical habitat of breeding Marbled Murrelets. Forest Investment Account (FIA) - Forest Science Program. Forest Investment Account Report. FIA2006MR307