Purpose and Background

• Commissioned by OPW: Mayfly Ecology developed a rapid survey method for arterial drainage schemes (ADSs) to assess river and habitat conditions effectively over extensive networks (11,500 km).
• Pilot Survey: Initially tested on Brickey ADS, highlighting the need for efficiency without compromising on the quality of baseline ecological data.
• Objective: Provide an overview of hydrology, habitats, and environmental conditions to identify key features and areas requiring further assessment.

Key Features of the Methodology

1. Scope and Application
   • Designed for large-scale surveys across ADSs.
   • Assesses hydrology, habitat quality, and potential habitats for sensitive species like otters, kingfishers, and Annex I habitats (EU Habitats Directive).
   • Not a substitute for detailed species-specific assessments but indicates areas for further investigation.
2. Desktop Review
   • Preliminary analysis using GIS tools (QGIS, ArcGIS).
   • Data sources include EPA, NPWS, NBDC, and OPW databases.
   • Targets habitat mapping, invasive species distribution, and Water Framework Directive (WFD) data.
3. Field Survey Methodology
   • Survey Approach: Covers riverbanks, channels, and adjacent land; subdivides river sections (~500–1000m) for focused assessment.
   • Spot Checks: A minimum of 5 to 10 per section to identify habitat diversity and potential features.
   • Seasonality: Optimal period is May-June, but surveys can extend from April to September based on local conditions.
   • Physio-Chemical Parameters: Measures dissolved oxygen, pH, conductivity, and temperature at key points.

Data Collection Parameters

1. General Information
   • Records site-specific details, including GPS coordinates, habitat classification (using Fossitt codes), shading, substrate composition, and water depth.
2. Photographs
   • Captures typical habitats and significant features (e.g., spawning grounds, otter holts, invasive species).
3. Species and Habitat Assessment
   • Salmonids: Evaluates spawning, juvenile, and adult habitats based on substrate quality, water depth, and riparian cover.
   • Lamprey: Focuses on spawning sites, nursery areas, and barriers affecting migration.
   • Otters and Kingfishers: Notes field signs (spraints, nests) and habitat suitability.
   • Bats: Highlights potential roosting sites (trees, structures).
   • Terrestrial and Aquatic Vegetation: Identifies dominant vegetation and potential Annex I habitats.
4. Invasive Species Biosecurity
   • Implements the “Check-Clean-Dry” protocol to prevent pathogen transfer.
   • Prioritizes upstream-to-downstream surveys to minimize contamination risks.

Survey Equipment

• Includes waders, waterproof notebooks, cameras, GPS devices, meters (DO, pH), and personal safety gear.
• Ensures preparedness for challenging terrains and seasonal variations.

Rating System

1. Habitat Suitability Ratings
   • A 5-point scale evaluates conditions (1 = Bad to 5 = Excellent) for species at various life stages.
   • Factors include substrate quality, habitat heterogeneity, and accessibility.
2. Specific Challenges
   • Barriers: Assesses the impact of weirs, culverts, and dams on species migration.
   • Water Quality: Correlates biological and chemical parameters with habitat suitability.

Output and Reporting

• Provides baseline ecological data for management decisions.
• Summarizes findings at the section and overall channel level to guide conservation efforts.
• Identifies critical habitats and areas requiring remedial measures or detailed studies.

Applications and Limitations

• Applications: Suitable for ADS assessments, WFD monitoring, and preliminary conservation studies.
• Limitations: Not comprehensive for species-specific requirements or population studies; further investigation recommended for significant findings.

This methodology balances efficiency and ecological detail, ensuring it is feasible for extensive networks while identifying conservation priorities. Let me know if you need further analysis of specific sections or habitat details.

Source

https://www.etenders.gov.ie/epps/cft/listContractDocuments.do?resourceId=4705304