Temperature at field sites
Daily maximum temperature at the four monitoring sites fluctuated
considerably, and the largest variation in temperature
occurred on days when spring low tides expose the meadows to
either hot day time temperatures and/or cool night time temperatures
(Fig. 1). There were 16 (Low Isles), 25 (Green Island), 10
(Dunk island) and 23 days (Magnetic Island) where water temperature
reached more than 35 C, which was 0.6–1.5% of days in the
5-year measuring period. There were no days above 40 C at three
of the sites, with just 3 days reaching 40 C at Dunk Island (two in a
row in May 2008 and one day later in September 2008), and there
was just one day reaching 43 C at Dunk Island in June 2008. On
this day, temperature ranged from a minimum of 23 C (data not
shown) to 43 C (20 C variation).