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Wetlands,
Biodiversity and Salt
Wetland Birds and Salinity
August 2006
Overview
Findings
Non-riverine wetlands provide important
habitat for birds, which are a prominent part of
the biodiversity of many ecosystems. Birds
perform important functional roles, such as
predation and grazing, in wetland ecosystems
and are very popular with a broad part of the
community. Consequently, it is important to
understand how birds respond to the
secondary salinisation of non-riverine
wetlands. Unlike other taxa, many bird species
can move relatively easily around the
landscape and may be able to respond quickly
to changes in their environment. It is these
attributes that may make some bird species
appropriate indicators of secondary
salinisation.
•
Several species, including Australian
Shelduck, Masked Lapwing and RedCapped Plover were positively associated
with wetland salinity.
•
Other species, like the White-faced Heron,
White-necked Heron and Latham’s Snipe were
negatively associated with wetland salinity.
•
Species number was typically highest in
the wetlands with intermediate salinities
(Figure 1).
•
Many of the wetlands with high species
number were secondary salinised
Aims and Methods
We examined the patterns of wetland use by
common bird species in association with
changes in conductivity, our proxy for salinity.
We surveyed wetlands in the Wimmera region
of western Victoria that varied in their salinity
regime and examined wetland use bird species
in each of the wetlands.
Many of the study wetlands were secondary
salinised and accordingly, we were also able to
determine whether the birds utilised these
wetlands.
A Victorian
Government
initiative
• Species such as the Red-Capped Plover that
are easily identifiable and were believed to
prefer more saline wetlands may be
candidate indicator species. The RedCapped Plover clearly inhabits secondary
salinised wetlands and, in our study, was
not readily detected in the fresh wetlands.
• We will continue to analyse our data and to
improve our understanding of the effects of
secondary salinisation on wetland birds.
Figure 1: Predicted relationship between wetland salinity and
species number. Solid line depicts relationship and dashed
lines show the degree of uncertainty. Top axis indicated
percentage of seawater.
Outcomes
• Several bird species were positively
associated with wetland conductivity,
suggesting that these species will
commonly utilise the more saline wetlands.
Red-capped Plover, Charadrius ruficapillus
Photo: Ian McCann
• Many used the secondary salinised
wetlands, indicating that increased salinity
is not a deterrent for some wetland bird
species.
• Some, like White-faced Heron, were not
readily detected in highly saline wetlands.
Published by the Victorian Government Department of Sustainability and Environment Melbourne, August 2006
© The State of Victoria Department of Sustainability and Environment 2006
This publication is copyright. No part may be reproduced by any process except in accordance with the provisions of the Copyright Act 1968.
Authorised by the Victorian Government, 8 Nicholson Street, East Melbourne.
ISBN 1 74152 657 4
For more information contact the DSE Customer Service Centre 136 186 or Dr Michael Smith on (03) 9450 8612 or [email protected], Arthur Rylah Institute, Department of
Sustainability and Environment, PO Box 137, Heidelberg 3084.
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particular purposes and therefore disclaims all liability for any error, loss or other consequence which may arise from you relying on any information in this publication.
www.dse.vic.gov.au/ari/
the Wetlands, Biodiversity and Salt project can be found by following ‘Research Themes’ to ‘Salinity and Climate change’