Notes on Swamp Sampling

Fish Pictures here So far 125 individual Banded Kokopu photographed and mapped. Check out the possible Giant Kokopu and the pics of the whitebait.

9 August - Michael, Andrew, Hussain - Determined one point at which the water drains under the sewer pipe. A walk in the swamp on the sea side of this revealed very shallow pools, but a reasonable flow with some endemic fish and Gambusia.

Overnight 15-16 August - Michael, Andrew - checked 5 trap sampling points. All traps 'baited' with lights. 3 floating traps had no catch. One of two bottom set traps had two banded Kokopu in it. One fish c 250 mm, the other c. 190 mm. Larger fish was dark with grey stripes - smaller fish an orange colour.

Overnight 22-23 August - Two bottom set traps baited with light downstream from previous place where Banded Kokopu caught. One trap = one adult Inanga = c. 120 mm long, one banded Kokopu = 50 mm long. Second trap = Banded Kokopu c 200 mm long - dark like the previous large one, but not as big - see photo and one female Gambusia. Water temp at both places 10 C.

Overnight 29-30 August - Four bottom set traps - two with light and two with cat food in pools in the middle of the swamp. One Banded Kokopu (?) caught - it escaped before we could get a good look at it! Light traps 0, baited traps 1. Water temp 13 C. At Gambusia sampling spot 15 C about 1/2 an hour later at 08h30.

Overnight 11-12 Sept - 6 bottom set traps all above the waterfall in large pools, baited with dog food. Water temp 13 C. Two traps with Banded Kokopu, (1)(2) and four without. Unexpected issues with flow pushing the traps out of position.



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Overnight 12-13 Sept - 6 bottom set traps below the waterfall, baited with dog food. Water temp 13.5 C (checked on 13th).
4 traps washed into bad positions and mostly compressed. Two traps in the pool below the falls (above). One trap short-finned eel(?) about 400 mm long. Other trap Banded Kokopu and female RED_FINNED BULLY - picture below
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Overnight 18-19 September - 9 traps set about 80 below the waterfall in suitable pools. Baited with dog food and marmite. Some habitat (gravel stream with reasonable flow over it) not sampled, but it needs to be. Water temp 12 C. Fish caught - 1 Long-finned Eel - difference in fin lengths noticable. 5 Banded Kokopu. No more bullys.

Overnight 25-26 September - 9 traps set in suitable habitat - all about 50 m or so upstream of the confluence of the iron stream tributary. All set in pools. One large fish seen c.15 cm of so - identity not sure. Water temp 14 C. Evidence of flooding at high water levels, with vegetation pushed over. This not seen anywhere else on the stream. Most traps moved by floods due to heavy overnight rain. 6 Banded Kokopu caught in two traps. Water very dirty.

Overnight 1st October - 9 traps set upstream of previous exercise. Water temp 12 C. 20 Banded Kokopu caught. Find the Kokopu in these pics!

Overnight 3rd October - 9 traps set. 3 in main stream and 6 up tributary 5. Lots of rain overnight so issues of movement again. No fish in main stream. 5 Kokopu in tributary 5. Major barriers at confluence of 5a and 5 = concrete/clay drainage pipes which control most flow and divert water away from stream bed. Gap is 15 cm or so = impassable for fish? Water temp 14 C

Overnight 7th October - 9 traps set downstream of trib 5 and main stream confluence. Water temp 11 C. 12 Banded Kokopu caught.

Overnight 8th October - 9 traps set downstream of last nights effort. Water temp 12 C. 1 Banded Kokopu caught - 2 whitebait also caught - check out the photo's page above to see what they looked like. Whitebait now known to be beyond the bifurcation bridge in the main stream and at least 100 m downstream of the Valley road boardwalk. Also some caught during a King tide at the Gambusia sampling site.

Overnight 9th October - 9 traps set below the first sewer line that crosses the stream and the main board walk from Valley road. Banded Kokopu caught and any number of whitebait. Sampling at the boardwalk revealed whitebait/Gambusia (including young of this year) and shrimps with eggs.

Overnight 10th October - 9 traps set downstream of the boardwalk. Banded Kokopu, Long-finned Eel (at last another one), Inanga, whitebait and Gambusia caught.

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