We used newer, larger-scale 2007 colour air photos to interpret habitat attributes and classify habitat quality of 14 Marbled Murrelet (Brachyramphus marmoratus) nest sites identified in 1992 (n = 2) and 1999 (n = 12) in Mussel Inlet on the Central Coast of British Columbia. Mussel Inlet is a fjordland environment atypical of other areas for which the air photo interpretation classification has been tested using nest sites (i.e., Haida Gwaii, Vancouver Island, and south coastal British Columbia). Nesting habitat described by 3-ha plots centred on the nest site was characterized in Mussel Inlet as having complex canopies with large trees in mid to low meso slope positions, and as such is comparable to that reported elsewhere in British Columbia. However, comparisons of the nest plot habitat attributes to those at 27 random plots also suggested that interpretations of murrelet habitat selectivity for Mussel Inlet differed from other coastal areas due to differences in characteristics and availability of forest structures. Overall in Mussel Inlet, more nest plots were classed as lower quality (i.e., 50% Low and Very Low) on air photos compared to other British Columbian studies (i.e., ~14% Low and Very Low). Although selectivity testing based on air photo habitat class was inconclusive, particularly for the High and Very High quality habitats for which limited habitat was available (~1 % of the study area), a trend was indicated for higher proportional use of Moderate and Low habitats and lower proportional use of Very Low habitats. We discuss limitations of the samples used for this study and issues in interpretation, resolution, and scale in applying the air photo methods in topographically complex, fjordland landscapes such as Mussel Inlet. Given these limitations and issues, we recommend use of aerial survey methods to confirm occurrence of nest platforms.
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Updated March 31, 2011