Following on from previous years of foraging studies in the Charleston area, during the 2023 season we carried out a pilot study at Camerons Beach, tracking the foraging paths of three blue penguins at chick guard stage, when one adult remains to guard and the other goes to sea to forage, over four days. We plan to carry out a more extensive study this coming season. This was the first time we have undertaken any study at the Camerons Beach colony and we plan to continue and expand this project during the 2024 season.

We hope this will give us an insight into the foraging areas and patterns of our local penguins in this more residential area of the West Coast.

Two important reasons for carrying out a foraging study are firstly, finding out what determines where the penguins are going to find their food source.  Sea surface temperatures? Chlorophyll amounts? Different marine conditions? And secondly, to understand and map where penguins go, which will help us contribute to marine science and spatial planning, to discuss with fisheries and overall, help us to protect our wildlife and the marine ecosystems they rely on.

We have carried out foraging studies in the past, at the Knoll and Rahui Colonies, close to the Nile River in previous years and it will be interesting to see the results of this year and make comparisons.

Read about these previous studies here.

Here are some maps and findings from the pilot study 2023 season:

Little penguin foraging tracks
Foraging tracks from the Camerons colony


Some key points were the average dive depth of 4.29m and average range from home of 26.02kms.

Just three dives of the several thousand recorded were over 20m.  In ‘ordinary’ foraging conditions, penguins will generally not be diving deeper than 10m.

The furthest point from home reached by these three penguins was 36.4kms.  Other data needs to be interpreted in light of battery failures before the loggers were recovered in 5 out of six trips.

The impact of climate change and marine heatwaves with likely increasingly adverse effects on little penguins is a concern.  The adverse effect is possibly due to intensified stratification resulting in reduced mixing of surface and deeper water.  Thus increases in turbidity after rain events take longer to dissipate because sediments are trapped at the surface.  As a consequence, the penguins have to travel further away from the coast to reach cleaner water where they can see adequately to catch prey.

Stratification can also disrupt the usual vertical nutrient flow potentially resulting in higher productivity and algal blooms at the surface, which may also inhibit visibility.

Key insights from data obtained so far:

  1. West Coast kororā showed very shallow foraging behaviour: mean maximum dive depth 4.29m. This could be due to a high proportion of travelling dives.
  2. Range for trips average 26.02 kms from home, the furthest being 36.4kms. Compared to a similar kororā tracking study that was conducted at the same time out of Port Taranaki, Camerons beach penguins travelled twice as far away from their nest sites to find food. This raises the question whether this is typical behaviour for the West Coast birds or a result of poor foraging conditions closer to the coast. Additional GPS tracking in 2024 will provide crucial insights.
  3. Results are similar to findings from an earlier study from the Charleston study colony with average an range from home of 26kms, some trips up to 36km from home with rare trips up to 60m from the colony, more parallel to coast than perpendicular.
  4. All tracks indicate foraging within 110m bathymetric contour approximately.

We are lucky enough to have some eager high school students wanting to analyse the data for us and make some charts and tables. It is always a really great opportunity for both the Trust and school students to collaborate with these sorts of things. Statistics is a compulsory topic at school and, in year 11, 12 and 13, all exams are statistics based, so what a great collaboration and a worthwhile and interesting topic for the students.

We look forward to some data analysis from the students soon, but we should note this is just year 1!  We won’t be able to read too much into data from three birds performing two foraging trips each though we may be able to review alongside our other foraging study results from Charleston. Our pilot study has however confirmed that this is an excellent study site and we are keeping in close contact with the Guardians of Paroa Taramakau Coastal Area Trust as we go.


Data logger in place