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Otaki College - Dawn Hirschberg

2015 | The Expressway: the upstream effects on Ngā Manu

SchoolOtaki College

HostNgā Manu Nature Reserve


Dawn has taught at Otaki College for 8 years, where she teaches general science and physics. She has an interest in conservation and New Zealand flora and fauna.

She has been hosted by Dave Banks, manager at Nga Manu Nature Reserve, Waikanae. She spent the early part of the programme collecting data about the water ways in Nga Manu Nature Reserve and the nearby Kakariki stream. The data included temperature, pH, electrical conductivity, water clarity, water levels and flow rates. Alongside this, she also recorded the presence of various invertebrates and fish she found in the different areas of interest.

She found that as the water levels within the reserve started to get very low due to the extended dry period that Kapiti coast experienced this summer, the existing weir that had been used for flow rate measurements, was not able to give reliable data during this time. As the water through the weir became lower, the water was moving too slow to get a valid reading. At times, the water took upwards of 30 minutes to move through a distance that during high water levels took a matter of 30 seconds!

The other extreme was also found to exist when the Kapiti Coast experienced very high rainfall. The weir went from being very slow to overflowing and the water no longer flowed through the weir consistently over the entire area.

For these reasons, it was decided to establish another flow rate measurement point. This lead to Dawn learning about measuring land levels and other methods of flow rate such as transparent velocity height recording. This particular method provides many learning opportunities for students, as it involves the concepts of increased height due water flowing around an obstacle.

Other aspects of her placement included:

  • Installation of a remote monitored weather station, for the collection of data for the use of Nga Manu, students and visitors to the reserve.
  • Seeing the mistletoe project that Rhys Mills has been developing over a number of years
  • Water spouts forming on the main pond on a hot summer’s day
  • Kiwi breeding with the new pair producing an egg
  • Visiting birds such as spoonbills and shags
  • Kohekohe being in bud from March until early June when the long dry finally broke and the flowers opened

Dawn would like to thank the staff and volunteers at Nga Manu Nature Reserve for their time and warm welcome during her time there. She also would like to thank the the Science Teaching Leadership Programme for giving her the opportunity to increase her understanding of the Nature of Science and to build her leadership skills. She is looking forward to working with staff at Otaki College as a new science programme is developed.