Sediment Monitoring Program - Maugean Skate Program

Summary and scope

The Department seeks a suitably qualified Supplier to design and implement a comprehensive Sediment Monitoring Project to: • quantify sediment oxygen demand, from organic and inorganic sources (including known heavy metals contaminants), within Macquarie Harbour • assess sulphur cycling processes within Macquarie Harbour and determine whether sulphur dynamics contribute to oxygen consumption, including characterising sulphur dynamics and their potential influence on benthic oxygen demand • update bathymetric information for key areas, primarily those known to be highly dynamic in nature such as the mouth, of Macquarie Harbour using contemporary multibeam technology to ensure sufficient resolution for environmental modelling and sensitivity analyses, noting that existing data is outdated. • determine appropriate Method(s) (e.g. environmental DNA (eDNA), grab sampling, etc) to monitor the distribution (historic and geographic) and biomass of Maugean skate key prey species, and if feasible and where appropriate, undertake targeted investigations to evaluate prey availability and any changes associated with environmental remediation efforts, and • consolidate environmental datasets relevant to sediment and benthic conditions, by updating the existing datasets with the most recent three years of available information. This Sediment Monitoring Project will support harbour-wide oxygen balance assessments and contribute to understanding the environmental conditions influencing the Maugean skate and its habitat. All work must complement and not duplicate the works being carried under the Oxygenation Offset Program for Macquarie Harbour’s Science Project. Works will be delivered through two stages: a Design Stage and an Implementation Stage. The Design Stage will include: • engagement with relevant stakeholders to capture current sediment monitoring practices and methodologies in Macquarie Harbour into a Draft Methodology; • identification of gaps, areas for alignment with best practice and/or overlaps in current monitoring activities, and capabilities assessment for delivering on the SMP; • refinement of Draft Methodology through alignment of current practices with a statistically representative sampling approach, inclusive of field procedures for collecting sediment cores and associated samples, identifying site distribution, seasonal replication and sampling frequency; validate feasibility of implementation through engagement with end-users and relevant stakeholders and integration of feedback into a draft and Final Methodology; and • preparation of a Consolidated Environmental Dataset Report for consideration by the National Recovery Team for the Maugean skate. The Implementation Stage will include: • operationalising the Final Methodology by establishing logistics, sequencing, safety considerations, and coordination with delivery partners (if required); • identifying any training required and, if applicable delivering training sessions and supporting material to ensure staff/partners can implement monitoring in accordance with the methodology; • conducting sediment coring and sample collection across all designated sites, with repeat sampling of a subset across different seasons; • laboratory analysis of all samples to quantify sediment oxygen demand and characterise organic (including biological) and inorganic sediment properties; • compilation of findings into a final report summarising spatial findings and any seasonal variations identified in sediment oxygen demand and implications for harbour wide oxygen balance; and • preparing a Final Consolidated Environmental Dataset Report that updates and extends the Initial Consolidated Environmental Dataset Report