Zanzibar Humpback Whale Research: Live Whalesongs Bring Goosebumps
It is an exciting time for the project as this year’s funding has finally allowed us to secure a local student’s involvement in our research, something we have been trying to achieve for several years now. Yussuf N Salmin graduates this year from Aquatic Environmental Sciences and Conservation, University of Dar es Salaamand joins us from Stonetown.
In true boaty style he had to pass through a few days of initiation out on the water until he got his boat legs. Joining us during Ramadhan Yussuf had his work cut out! One of the most important aspects of incorporating a local student into the research project is for technology and equipment training, including Camera and GPS.
Yussuf has integrated well into the team and is becoming familiarised with our routine and data collection efforts. His camera skills are improving daily as he becomes more comfortable on the boat with each passing day. It is hoped that once he is familiar and confident with the equipment this knowledge can be passed down to fellow local students. The aim is to have a self-sustainable project, including whale and dolphin research, allowing a year round presence here in Kizimkazi Dimbani, including continuous dolphin research. Such project goals are only achievable with essential funding and wouldn’t be possible without the kind and continuous financial aid from our supporters.
Yussuf’s arrival was also at a time of rough seas and stormy weather (up to Beaufort sea state 5 with 2m swells) but today still we managed to get out and survey the waters until an impromptu downpour ensued and made it impossible to continue. Unfortunately our capi captains don’t yet have waterproofs and had to take shelter under our waterproof sheets that house the equipment. ‘Polesana’ them! This is another area whereby further funding would be mighty useful. As the skies opened Rachael and Kristin donated one waterproof jacket to Foum who had to endure the downpour as he drove the boat and they shared the other between them.
Khamis remained under the sheet and Lucy was on boya watch as we headed back through the maze of nets. This season in addition to having competitive pods and mother/calf pairs we have also once again had singing males around the coastal waters of Zanzibar, all of which are indicative of humpback whale breeding grounds. In order to determine if there are any singing males present in the area opportunistic hydrophone drops remain part of our daily survey efforts, weather permitting. Rough weather, especially at the start of the season, has often hindered acoustic data collection with sea states too rough for safe use of equipment, increasing interference levels of potential recordings.
However from the start of the season (July 2011) to date (September 2011) we have detected thirty incidences of singing whales in the area. The song is continuous and comprised of arrangements of vocalised components, in which units make up phrases and phrases make up themes. In order to inform each other of what we are hearing during a successful hydro drop, common themes heard this year have been fondly named as ‘cow’, ‘crying dog’, ‘engine’ and the well known ‘beautiful song’, one which is always a pleasure to hear and hearing the live version brings goose bumps to your skin. Themes differ from region to region and can in theory be used to identify spatially differing populations of migratory humpbacks although certain favoured themes can also be adopted by passing whales and adapted and incorporated into arrangements. During hydrophone drops and recordings we remain on effort as they whales may surface to breathe between themes, and also other whales may still be present in our survey area.
Although the whales are singing, many have been too distant to record, or weather has made it difficult for recordings; but these unrecorded acoustic detections still indicate that this location is indeed a breeding area, potentially part of a much larger breeding ground for humpback whales. Exciting analysis of the data will being carried out once the season is over as time out in the field is filled fully with data collection efforts and every day village living.
After a busy day out on the water and as Zanzibar tries to address its problematic power supply with now scheduled 1-2 hourly power cuts we again are plummeted into darkness with hamna umeme (no electricity) but still the work must go on, so that day’s data gets entered by candlelight Lucy’s time out in the field is drawing to an end. In addition to heading back to England to catch the end of British summertime and enter her final year at university Lucy will be analysing the behavioural data we have collected and she has lots to work with as it’s been a busy survey season including many competitive pods, surface active singletons and mother calf pairs to name but a few! It’s been a pleasure so tutaonana baadae from us and the whales!
Meal of the week: Lucy’s farewell meals; two of her favourite dishes; Coconut rice (Speciality de Mau) and Samaki (fish) Pilau (Speciality de Foum). Talk about going out in style! -- Rachael - The Zanzibar Humpback Whale Research Team