Otago Fish & Game demonstrated electrofishing and trapping to give the students an idea of fish species present in Lagoon Creek.
The pupils are taking part in a wider project to monitor water quality and biodiversity in Tomahawk Lagoon and its catchment.
The multi-school project is facilitated by EC Otago Charitable Trust through its trustees Andrew Innes, Dr Murray Vickers and Dr Jonathan Kim.
Queen’s High School science teacher Tom Clark said the school took a group of 15 year 10 pupils to Tomahawk Lagoon about once a month to carry out water monitoring.
"Students take water samples for E.coli bacteria and look at the nitrogen and phosphorus levels, as well as water temperature, pH, turbidity and conductivity.
"They also sample for fish species and macroinvertebrates."
Mr Clark said, as part of the school’s year 10 botany programme, they were working with EC Otago and BeachCare Trust along with the landowner to carry out riparian planting to try to improve the water quality of the creek and lagoon.
Fish species present in the creek would be monitored over the coming years as the riparian planting developed.
This year all Queen’s High year 10 students also went to the Smaills Beach reserve to collect native seeds with Nicole Bezemer from BeachCare Trust.
"They are now growing the seeds as part of their botany programme," Mr Clark said.
Joining the pupils, Fish & Game officer Steve Dixon caught and released juvenile perch using electrofishing equipment and set Gee’s minnow traps, catching live common bullies and more perch.
Mr Dixon said as urban and rural waterways came under increased strain, he was pleased to see pupils, as the next generation of guardians, learning how to care for their environment.
"Tomahawk Lagoon provides habitat to freshwater fish species including common bully, giant bully, koura, longfin eel [tuna], inanga, brown trout, rainbow trout, perch and invertebrates.
"It’s also home to taonga waterfowl such as paradise shelduck/pūtakitaki, New Zealand shoveler/kuruwhengi, and black swan/kakīānau, and pukeko, as well as introduced mallard, which are all managed by Fish & Game, and New Zealand scaup, Australasian coot and rare marsh crake.
"The upper lagoon is a popular and easily accessible recreational fishery."
Mr Innes said the project data collected would contribute towards a robust picture of how the environmental health of the lagoon and its streams changed as a consequence of restorative riparian planting.
"The planting is proceeding this winter, so watch this space," Mr Innes said.
"The project also encourages the students to appreciate the science behind their observations and develop their own investigations to better understand what is happening at their monitoring sites and the wider ecosystem."
Other schools involved are Tahuna Normal Intermediate, Bayfield High School, Otago Girl’s High School, and King’s High School.
— Otago Fish & Game
