IB students join with other Dunedin schools to monitor water quality at Tomahawk Lagoon.
McGlashan students have had a long history with this body of water. It has been the focus of the IB Diploma 3- day science project run in November over many years. Last year however, ECOtago began a longitudinal monitoring study of the lagoon, looking at it's biodiversity and water quality and this provided our students an excellent opportunity to become involved in environmental science in a real-world context.
On a perfect February morning, around 25 students from across Dunedin were trained in a wide range of techniques, enabling them to collect water samples, measure oxygen concentration, water salinity, temperature, depth, nitrogen & phosphate concentration, and eColi contamination. Bird counts, and biodiversity observations of plant and animal life are also made of the lagoon. All data is logged and analysed to help create a meaningful story about the health of this important local waterway.
Students were intrigued to discover that the overall health of the lagoon tends to go in 2-3 year cycles. Currently, there are two different algal blooms occurring in the two arms of the lagoon - one causing a green tinge and the other a reddish tinge (OK - not quite maroon, but I wasn't about to pass up a rhyming opportunity like that!) Hopefully our monitoring will uncover the reasons for this interesting phenomenon.