How can we protect shorebirds foraging habitat near wastewater treatment plants ?

By Liz Morris, David Petch, David May and William Steele.

Sint red neck

Red-necked stint feeding in intertidal mudflats. Credit: Doug Blood.

Monitoring for a specific management objective: protection of shorebird foraging habitat adjacent to a wastewater treatment plant

This article was published online in Environmental Monitoring and Assessment on 6th April 2017 and can be found here http://rdcu.be/qJxO. For more information please contact Liz Morris e.morris@unimelb.edu.au.

Abstract

Intertidal invertebrates are often used in environmental monitoring programs as they are good indicators of water quality and an important food source for many species of fish and birds.  We present data from a monitoring program where the primary aim is to report on the condition of the potential invertebrate prey abundance, biomass and diversity for migrating shorebirds on mudflats adjacent to a waste water treatment plant in a Ramsar listed wetland in Victoria, Australia. A key threat to the foraging habitat at this site has been assessed as a reduction in potential prey items as a result of the changes to the waste water treatment processes. We use control charts, which summarise data from intertidal mudflats across the whole shoreline of the adjacent wastewater treatment plant, to elicit a management response when trigger levels are reached.  We then examine data from replicate discharge and control sites to determine the most appropriate management response. The monitoring program sits within an adaptive management framework where management decisions are reviewed and the data is examined at different scales to evaluate and modify our models of the likely outcomes of management actions.  This study provides a demonstration of the process undertaken in a year when trigger levels were reached and a management decision was required.  This highlights the importance of monitoring data from a range of scales in reducing uncertainty and improving decision making in complex systems.