Ground-dwelling spider community recovery five- and eleven years post harvest in boreal mixedwood forests

Clear-cut logging is extensively used to harvest boreal forest across Canada and its immediate effect on the biota has been well relatively documented (e.g. loss of forest specialists and colonization of early successional species). However, the point at which clear-cut stands begin to recover is unknown. To investigate this, epigaeic spiders were studied in three regenerating spruce stands and three of aspen at five- and 11 years post-harvest. Three mature control stands of each of these stand types were also examined to give a reference to unharvested conditions. Spiders were collected using pitfall traps over a 12 week period during the summer of 2010 in Northern Alberta. Results showed that five year post clear-cut spider assemblages were similar irrespective of pre-harvest forest type, whereas the 11 year post clear-cuts differed: the deciduous stands began to converge with control stands of that type, whereas the conifers remained distinct. Overall, species richness was generally greater in the second sampling year and did appear to be related to treatment (clear-cut or control). Common species of mature deciduous forests were found frequently in both five and 11 years regenerating stands whereas several species common in mature conifer forests had not colonized at five or 11 years post clear-cut. Findings suggest that pre-harvest forest type influences spider fauna recovery after clear-cutting. Deciduous stands respond more quickly, probably because conditions in 11 year regenerating stands are more similar to the mature state. Unique species supported in conifer stands do not colonize as quickly suggesting it will take longer for these forests to recover.