I am now in the third year of my PhD and I am blogging from Duke University, North Carolina. I have been taking post-graduate classes that focus on habitat modelling and geospatial analysis. I will be applying the skills I have learnt here to analyse our dolphin data that we have collected in Bunbury, Western Australia as a part of the South West Marine Research Program. It has been a great opportunity to be a student at Duke and to learn from and work with lead researchers; Associate Prof. Patrick Halpin, Prof. Dean Urban and Dr Dave Johnston. I have enjoyed being in a new environment and watching the seasons change from winter to spring.
Whilst I have been at Duke University, the dolphin research has continued in Bunbury, south west Australia. Dolphin surveys are traversed along zig-zag transect lines covering a study area of 540km2. Interestingly, when our research associate, Krista Nicholson, took over in January, there were several dolphins observed with emaciated body conditions. The calves, “Bana”, “Chippy”, “Milkyway” and “Magic”, displayed post-nuchal depressions on their heads, which is also colloquially known as “peanut heads”. However, the reason for why these calves are in poor body condition is not known.
One of these calves, Chippy, may have a poor body condition because it’s mother “Lunchbox” went missing in early December. Lunchbox was a successful mother and had raised three previous calves, “Popper”, “Bistro” and “Esky”. Lunchbox remained with her calves for around four years before the calves became independent. However, Chippy is less than two years old, so it would still most likely need to rely on Lunchbox. Instead, Chippy has been seen close by with sub adults “Calypso” and “Koomba”. However, in February Chippy was bitten by a shark and has not been re-sighted since.
In addition to Chippy’s shark bite, there have been eight other confirmed shark bites on dolphins over the summer season. There were different degrees of severity of the bites and none were fatal. The bites were on the adults “Star”, “Smiley”, “Frenchy” and an unidentified dolphin; on the juvenile “Enigma” and on the calves “Splinter” and “Len”.
During this birthing season, which coincide with the warmer waters, eight new calves were born; “Diver”, “Vampire”, “Venus”, “Biro”, “Nova”, “Isma”, “Topping” and “Dori”. Dori is the calf of “Mrs Iruka”, which means Japanese for dolphin. Mrs Iruka is a “begging” dolphin that approaches boats in the hope for free food, for example from the off cuts from fisherman. Unfortunately, Mrs Iruka has also been bringing Dori close to boats. This behaviour is not a natural dolphin behavior and can cause that dolphins become conditioned to humans, resulting in heightened risk of boat strike, ingestion of fishhooks and entanglement in fishing lines. To avoid any negative outcomes please do not feed or touch wild dolphins.
Our Austral summer season is now complete (December- February). We were on the water for 154 hours, encountered 81 dolphin groups and collected 45 benthic sampling images. Krista and I would like to thank our assistants that helped during this time; Virginie (Switzerland), Kim (Netherlands), Katrina (Shetlands), Victoria (England), Elena (England), Grainne (Ireland), Lauren (Australia) and Eloisa (Australia). Thank you and good luck to you all in the future. I would also like to thank Krista for all her hard work over the past months which rounds out the data collection portion of my PhD. Now it’s time to analyse and write my thesis!
The research for the South West Marine Research Program is made possible through the support from our funding partners, including, the Bunbury Dolphin Discovery Centre, Bemax Cable Sands, BHP Billiton Worsley Alumina, Bunbury Port Authority, City of Bunbury, Cristal Global, Department of Environment and Conservation, Iluka, Millard Marine, Naturaliste Charters, Newmont Boddington Gold, South West Development Commission and WAPRES.