Leanne Fernandes

Designing Marine Reserves for Fisheries Management, Biodiversity Conservation, and Climate Change Adaptation

Overfishing and habitat destruction due to local and global threats are undermining fisheries, biodiversity, and the long-term sustainability of tropical marine ecosystems worldwide, including in the Coral Triangle. Well-designed and effectively managed marine reserve networks can reduce local threats, and contribute to achieving multiple objectives regarding fisheries management, biodiversity conservation and adaptation to changes in climate and ocean chemistry. Previous studies provided advice regarding ecological guidelines for designing marine reserves to achieve one or two of these objectives. While there are many similarities in these guidelines, there are key differences that provide conflicting advice. Thus, there is a need to provide integrated guidelines for practitioners who wish to design marine reserves to achieve all three objectives simultaneously. Scientific advances regarding fish connectivity and recovery rates, and climate and ocean change vulnerability, also necessitate refining advice for marine reserve design. Here we review ecological considerations for marine reserve design, and provide guidelines to achieve all three objectives simultaneously regarding: habitat representation; risk spreading; protecting critical, special and unique areas; reserve size, spacing, location, and duration; protecting climate resilient areas; and minimizing and avoiding threats. In addition to applying ecological guidelines, reserves must be designed to address social and governance considerations, and be integrated within broader fisheries and coastal management regimes.

Spatiotemporal variability and environmental determinants of invertebrate assemblage structure in an Australian dry-tropical river

We described invertebrate assemblage composition over a range of spatial and temporal scales in the Burdekin River, one of northern Australia’s large and variable dry-tropical river systems. Invertebrates were abundant but not diverse, and the assemblage structure exhibited considerable variability in space and time. Substratum and historical flow characteristics were important environmental factors influencing assemblage structure. The effect of substratum on invertebrate assemblage composition appears to be complex and operates over multiple spatial scales within the riverine habitat hierarchy. The fauna differed significantly among the major mesohabitat types (cobble, bedrock, and sand substrata), but divergent microhabitat-scale preferences of some taxa for finer or coarser sandy sediments demonstrated the importance of small-scale local factors in structuring invertebrate assemblages. The significant influence of antecedent hydrology coupled with pronounced spatial variation in site assemblage composition between qualitatively similar mesohabitats suggest that biomonitoring in variable, sand-bed rivers will benefit from standardization of sampling in relation to explicit flow and substratum characteristics to assess spatial and temporal changes in assemblages adequately.