SUMMARY SITE RECORD FORM AND COMMENTARY DATE: 4/9/10

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1 SUMMARY SITE RECORD FORM AND COMMENTARY Where are you? DATE: 4/9/10 What is the weather like? Air temperature Wind direction and speed Cloud cover What is the time, and what stage is the tide? What is the condition of the Leith? Check websites (Met service and Port Otago) Is there anything unusual to report (dead crabs, nasty smell, coloured sheen on the water)? Discharge pipes Any star fish?? Rubbish or litter. Special seaweeds #81 very strong wind, SWs, no cloud cover #82 very strong wind, SWs, no cloud cover #83 very cold, strong southerly, clear skye #84 Strong wind driving into the bay, no clouds cover, very cold #85 Cold strong southerly wind, knots, gusting higher, raising spray cold south westerly coming down the river in gusts, ripples/chop, #86 protected from the swell by shelter #87 Fine conditions, 40 km/hr wind, less than 10% cloud cover fine, 40 km/hr, less than 10% cloud cover #81 10:20, very close to high water #82 10:20, very close to high water #83 10:40, close to HW # # pm, slack water just after HT # , steady tidal outflow #87 9:50 10:10 lot of different algae on the shore, sea lion swimming by, it was difficult to #81 take readings as the water swept in and out. lot of different algae on the shore, sea lion swimming by, it was difficult to #82 take readings as the water swept in and out. strong winds blowing down the harbour, many black backed gulls, sea #83 grass floating on the water #84 Lots of debris being blown into the bay, foam, sea lettuce and an old tyre #85 Rocks/shoreline clear of any obvious organic matter #86 water carrying many organic bits, mainly near the shore #87 choppy choppy What condition is the surface of the water? #81 choppy/ frequent gusts #82 choppy/ frequent gusts #83 Rough and choppy #84 waves and foam #85 very choppy, significant swells with white caps 2-3 cm chop, cm/s flow rate of surface #86 water

2 #87 slight;y frothy slightly frothy Does the water have any real, or apparent colour? Describe any movement of the water. Wind effect Slack/ebb/flood #81 the water is clear with normal green #82 the water is clear with normal green #83 Nothing unusual about the colour #84 dark green with lots of sediment greenish around pier, brown in the channel 100m #85 away #86 greenish #87 grey green brown No data gathered Understanding Estuarine Processes SITE RECORD FORM What is the water temperature? # # #83 8 # # # # What is the salinity and conductivity of the sample? # # # # # # o C

3 #87 Ppt # /42.1 # /42.1 # /44.84 # /40.8 #85 # / #87 What is the ph of the sample? # # # # # # # What is the water clarity? Comment #81 khaki green, clear #82 khaki green, clear #83 murky #84 #85 murky green/ 1 m visibility #86 light green murky, about 1m visibility #87 ms/cm What is the oxygen concentration of your sample? Measure both methods mg/l and % saturation # # # #84 nd # # NTU

4 # mg/l # # # #84 nd # # #87 % saturation What is the chlorophyll a concentration of the sample? Record the volume of water filtered # # # # # # # µg/l What is the concentration of the soluble phosphate in the water sample? ( filtered) # # # # # # # µmol/l What is the concentration of nitrates + nitrites in the water sample? # # #

5 # # # # What is the enterococci count in the sample? #81 5 #82 1 #83 2 #84 6 #85 nd #86 1 # µmol/l colonies indicated /100mL Commentary on our big day out on Otago Harbour Sept 4 th 2010 What was the day like? The day was challenging in the very exposed areas like the lower harbour at Pulling point and Mussel Bay. Cold strong gusty SW/W winds were blowing down the harbour with occasional gusts up to 40 knots around midday. This was sweeping water around and making the reading of instruments tricky. The sky was clear to about 10% cloud cover..the illusions of a clear sunny day! Little rain has fallen over the last two weeks, 20.0mm falling. Waters of Leith was flowing at cumecs. High flow rate on 30 th August, up to 14 cumecs. Last value of the water temperature in the Leith was 5.1 o C. This is lower than the ambient temperature at the mouth of 8.3 o C. Not warm!!! Tide and harbour conditions: All sampling occurred around high tide (2.0m) at am. Sampling carried out between 9:50 and 12:50. Is there anything unusual? The observers needed to be looking hard at their places!! At Pulling point ( #81/2) the tide was high, the wind strong so much debris was being swept on to beach. Instrument readings seemed to fluctuate with the gusts and currents in the water. We were visited by a lolling sea lion who was taking an interest in the work from the channel. Lots of algae ( Hormosira, Sea lettuce and sea grass) Many black backed gulls. Lots of debris being blown into Mussel bay. What are the tyres doing there? Conditions of the water surface

6 Very choppy water, frequent gusts sweeping the surface water before the wind. Lot of foam. Does the water have any real or apparent colour? The water in the lower harbour was clear with a normal green colour. Despite the wind the water in this area is above rock shelves so minimal turbidity present. In Mussel bay the water was dark green with large amounts of sediment and organic material. The colour in the channel some 100m away was brown. At other sites the water varied from green to grey green and brown. Water temperature. Ranged from 7.0 ()-9.1 o C (#81), again a noticeable gradient away from the mouth to the head of the harbour. [August 7 th o C, not much different] Salinity. The salinity was quite uniform as expected from the sites tested. The waters of Leith was slightly lower as the freshwater mixed with the seawater. NOTE on Electrical conductivity. The two conductivity readings are explained below _ Conductivity -- A measurement of the conductive material in the liquid sample without regard to temperature _ Specific Conductance -- Also known as temperature compensated conductivity which automatically adjusts the reading to a calculated value which would have been read if the sample had been at 25o C (or some other reference temperature which you choose). See Advanced Setup ph. 7.7(#87) 8.4 (#83/86), mainly [ August 7 th ] ph values look very similar to August with the exception of one site. Clarity The water was described as khaki green, murky green, visibility in some places limited to about 1m. [Quite different from August 7 th..the water very clear ] What a difference the weather makes to the clarity of the water. The harbour is relatively shallow so strong wind will mix the water quickly with the sediment. Dissolved oxygen (DO) mg L -1 and % saturation. Range 7.92 (#87) (#81) mg L -1 and %. [ August 7 th mg L -1 and %] Water is well oxygenated as expected at these temperatures and water agitation. Chlorophyll a. Range 0.9 (#81) 3.87(#84) µg L -1 [August 7 th no detectable level (#08)-2.50 (#81) µg L -1 Overall the values are higher than August. DRP ( dissolved reactive phosphate) filtered samples. Range from 0.37(#87)- 0.77() µ mol L -1 [August 7 th undetectable -0.79] DRP at a similar level to August, no significant spikes. NNN( total nitrates and nitrites). Range of 0.18 (#83) 25.93(#86) µ mol L -1 [ August 7 th µ mol L -1 ] The pattern is similar to August, the freshwater sources are significantly higher than the marine input as measured at Pulling point (#81/82). Enterococci. Range from 1 (#82/86) 60 (# 88) cell/100ml sample. [ August 7 th 2 (#81)-uncountable ()] Again, Mac bay storm water shows out as a site of concern.

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