UBC Theses and Dissertations
Evaluation of design, environmental, and sustainability attributes affecting urban fisheries restoration habitat in Vancouver, British Columbia, Canada Slogan, James Randolph
This thesis examines how structural complexity and environmental variability affects biodiversity and species assemblages on an engineered intertidal habitat named the Habitat Skirt, and develops a rapid assessment tool (RESTORE) to evaluate the long-term sustainability of restoration areas based on ecological, social and economic indicators to inform adaptive management. First, I tested how species diversity and assemblages on the Habitat Skirt compares with riprap; and if differences can be explained by environmental factors. Diversity at the Habitat Skirt and rip-rap were similar; however, species assemblages were not (P = 0.021). Species assemblages on the Habitat Skirt were dominated by Mytilus trossulus, while riprap had greater diversity of macroalgae. Both light intensity and water motion accounted for significant variation among species assemblages (P = 0.008; P = 0.019). Light intensity was positively correlated with macroalgal cover (P = 0.014); and both were lower at the Habitat Skirt (P = 0.001) then riprap. When constructing shoreline infrastructure with limited buffers to reduce shading, habitat managers need to determine whether potential differences in species composition meet regional coastal management objectives. Second, I examine intertidal assemblages and diversity among four microhabitats on the Habitat Skirt. Species richness was greatest within tidepools from two to four metres above chart datum (m CD) and vertical habitats at zero and one m CD. Richness decreased with increasing tidal elevation, except in tidepools where richness remained similar irrespective of tidal elevation. Species composition of many microhabitats varied with tidal height, these did not change significantly during the last two years. These results show that the relative effectiveness of microhabitats vary with tidal height. Lastly, I develop a tool, RESTORE, for assessing the sustainability of restoration areas using 25 ecological, social and economic attributes. I use RESTORE in a case study to examine differences in sustainability among marine, estuarine and freshwater ecosystems. Sustainability was significantly higher in marine than estuarine restoration areas (P = 0.029) with no significant relation of area on sustainability after controlling for ecosystem. RESTORE was successful in comparing a 25 attributes to assess the long-term sustainability of restoration areas to inform future adaptive management.
Item Citations and Data
Attribution-NonCommercial-NoDerivs 2.5 Canada