Year 12 Biology Blue Cod Field Trip

Sunday 2nd April 2023

As part of their NCEA studies the Year 12 Biologists went on a fishing expedition out of Moeraki to collect data for a practical investigation internal and an ecology internal.

Measuring fish for practical investigation internal
Measuring fish for practical investigation internal

 The day started out splendidly with a light sea, awesome sunrise and only a little chill in the air. The first stop yielded mainly only a few Jock Stewarts but catch rates of both them and blue cod picked up a little at subsequent stops. Despite a number of students “feeding the fish” most had a thoroughly enjoyable time. There was an informal competition to “catch” the most data and Georgia Spek won this with 5 blue cod. Overall handline catch rates were down on last year and we were grateful for cod pots which supplied additional data. Even with this only 73 blue cod were caught and measured compared to more than 100 last year. Other highlights included a single terakihi and red gurnard. The most notable catch of the data was easily the 110cm kingfish landed by Harry Willis. The students were looking at head/eye ratio as a predictor of length of blue cod for their practical investigation as a tool for measuring fishery health. As with last year there was no correlation found between the two. This was an interesting finding as a study at Leigh found a strong correlation for six different species. Next year we intend to examine fish weight as well. In terms of ecology we now have two years of data to analyse – students will be writing this report next term. 

Measuring fish for practical investigation internal
Harry and kingfish
Charlie and terakihi
Georgia with the first blue cod of the day
Charlie and Cory with Jock Stewarts