Appendix D_Shorebird_survey_report_Final_Jul20_jans edits

5.       Survey methodology

Weather permitting, surveys were conducted monthly commencing in October 2005 through October,
2019. A total of 151 surveys have been undertaken to date (90% capture). A schedule of surveys
conducted is provided in Appendix 1. Prior to 2005, no systematic survey of shorebirds in the Noosa River
estuary was known to have taken place.

Surveys were generally undertaken 4 - 5 weeks apart to ensure migratory species were not missed due
to those shorebirds having already arrived and departed from the survey area. The only exception were
surveys conducted in December and January which were generally scheduled up to 6 weeks apart to
avoid peak holiday disturbances in the survey area. Surveys were conducted regardless of the specific
lunar cycle (and hence tidal range) at the time.

Most surveys consisted of two “windows” of observations, conducted on the same day 13. The first
commenced approximately 1.5 hours prior to the “day light” high tide at Noosa Heads and ended
approximately 1.5 hours following that high tide. During high tides, shorebirds in the survey area were
more easily observed as they congregated on the elevated sand banks and permanent islands. The
second intra-day survey, for the purpose of more accurately assessing tern numbers in particular, was
made approximately 40 minutes prior to and following sunset. This survey was conducted from an elevated
position on the river mouth training wall. During the period around sunset, terns feeding in Laguna Bay
and further afield were observed to return to the estuary through the river mouth at relatively low elevation
and when observed against the evening light permitted accurate surveying in flight.

By counting terns in this manner, a
practice pioneered in this survey, a
more accurate assessment of overall
population     numbers      of   birds,
particularly migratory tern species, in
the estuary was established.

Appendix 3 provides further detail on
count variations observed for specific
species of terns between day and
evening survey windows.

Observations of individual birds and
flocks were validated by multiple
observers using high magnification
binoculars,    spotting scopes and
digital cameras.
                                                        A mixed flock of terns returning at sunset to the Noosa River estuary as observed
                                                        from the river mouth training wall. Credit: Jill Dening


Where possible, birds were counted
individually, though in the case of larger
flocks or flocks in flight, particularly terns,
other counting techniques were used from
time-to-time to derive more accurate data.
These included grid studies, proportional
counts and time elapse studies.

Notes on roosting, foraging and, where
relevant, breeding behavior were taken as
were records of tide, precipitation, wind
speed and direction and other relevant
climatic conditions.

Counts were conducted in accordance with
relevant survey protocols.
                                                               Survey Group volunteer, Barbara Dickson, conducting a count from Site 2
                                                               opposite Noosa Woods. Where possible, observers use high magnification
                                                               spotting scopes on fixed tripods to assist counts. Credit: Jill Dening.




13
     A total of 128 surveys (85%) including both day and evening counts, of the 151 surveys conducted.

Noosa River – Shorebird Survey Report 2019                                                                                          Page 8