Zanzibar Humpback Whale Research Project 2012

Blog 10: Hydro Buoy, 04/08/2012

Although the lighthouse pilot study is completed we are still very busy especially now that Jake Levenson from our funding agency the International Fund for Animal Welfare (IFAW) has arrived. The team is excited, not only to enjoy Jake’s company, but also because he brought with him an additional tool for the humpback whale research – a recording hydrophone buoy (underwater microphone). The hydrophone will be used for nearly continuous acoustic recordings of all underwater sounds including dolphins, whales, vessel activities and any other sounds occurring in the waters in our study area off southern Zanzibar.

 Jake Levenson preparing the hydrophone buoy for deployment.

The hydrophone buoy will remain deployed for the rest of the 2012 season and, once retrieved, will provide the project with additional data on the day-and-night acoustic presence of humpback whales and other underwater sounds. It was an interesting process deploying the hydrophone buoy; we had to decide on a location, to minimise noise from reefs (reefs are noisy places!) and the coastline, where waves crash onto shore. In the end, the hydrophone buoy was deployed in an area commonly used by Indo-Pacific bottlenose dolphins (Tursiops aduncus) and Indo-Pacific humpback dolphins (Sousa chinensis) and also where we previously have recorded humpback whale song. Humpback whales sing on the breeding and mating grounds and it is believed the males do this either to attract females or to express their breeding fitness to other males. With these recordings, in addition to data we collect during boat-based hydrophone recordings, the project will be able to compare humpback whale songs throughout the season and between seasons.

Captain Foum on our survey vessel on the way to deploy the hydrophone bouy.

The buoy was anchored to the seafloor at a depth of 13 m and will remain there for approximately 6 weeks until the end of the season. Prior to deployment a sampling rate (times throughout the day it will record acoustic data) was chosen to ensure battery life across the full extent of the deployment period – you would not want to discover that the batteries died halfway through the deployment.

Foum preparing the ‘anchor’ which will be used to hold the hydrophone buoy in place.

Abas, a local friend & divemaster, who dove with Jake to deploy the hydrophone

Khamis, our local captain, with the hydrophone buoy.

Abas post-dive: texting while diving?

Many thanks to Jake for bringing the exciting new piece of equipment to the Zanzibar Humpback Whale Project; the data collected from the hydrophone buoy will help us assess the occurrence and singing behaviour of the whales and other noise including vessel traffic, offshore oil and gas activities, dynamite fishing and other human or natural sounds off southern Zanzibar.

Pictures © Zanzibar Humpback Whale Project

Zanzibar Humpback Whale Research Project 2012

Blog 9: A Friendly New Face, 03/08/2012

On the 29^th of July the team was very happy to welcome a new local student to the Zanzibar Humpback Whale Project. Khamis Khamis is a second year undergraduate student at the University of Dar Es Salaam where he is studying for a Bachelor of Science in Aquatic Environmental Science and Conservation. Khamis is happy to join the Project this year and hopes that this experience will give him further knowledge about the whales around Zanzibar. Karibu Zanzibar Humpback Whale Project, Khamis!

Nat, Yussuf, Khamis & Lynne

After an incredibly busy ten days of conducting both lighthouse and boat-based surveys we finished the lighthouse pilot study on Friday the 3^rd of August. Overall, the addition of the lighthouse surveys resulted in more logistics for the team; every day we were busy working in sub-teams for boat and lighthouse surveys so had to organize food for both teams, coordinate timing of boat departures and travel by car to Makunduchi, and established new data collection protocols and their related databases. Despite the additional effort the team was very pleased with the data we collected from the Makunduchi lighthouse!

Makunduchi, on the southeast end of Zanzibar (Unguja) Island, appears to be one of the most popular areas for the whales in our survey area; almost every morning we receive fisher’s reports of whales and we often observe them there while conducting boat-based surveys. It takes about one hour to travel by survey boat from Kizimkazi-Dimbani to Makunduchi and, being more exposed to the open sea of the Indian Ocean, we are often unable to survey in the area due to the less protected, rougher seas that often occur here. The opportunity to conduct land-based surveys at Makunduchi allowed us to collect previously inaccessible data.

View from Makunduchi lighthouse looking up the east coast of Zanzibar

View looking down from the Makunduchi lighthouse

Over the course of the lighthouse pilot study, whales were seen almost every day and their behaviour and respiration rates could be easily recorded…whale blows are easy to spot when you are viewing an expanse of sea from 44 m above sea level! We collected data on their behaviours and respiration rates and were able to do so in a way similar to our boat behaviour surveys. We could time the surface intervals (times the whales were at the surface breathing between dives) and a variety of behaviours including traveling, resting and socializing. It was spectacular watching huge breaches, often multiple ones, from the lighthouse! One day we had a wonderful observation of one animal doing nine pectoral-fin slaps in just over a minute, just off the shelf edge below the lighthouse! In addition to tracking the whales’ movement we performed boat scans at regular intervals with the intention to collect data on interactions between vessels and whales.

Kristin keeping out of the sun while scanning from the lighthouse

By conducting land-based surveys from the lighthouse we could easily track animals in the area and had so much success viewing animals that we had to establish a protocol for tracking multiple groups of whales. We had to decide which, of often many, groups of whales we would track and for how long we would focus on an single group. By the end of the ten day study we had figured out what to do when we had multiple sightings at a time…which was the case most days!

Yussuf scanning from the lighthouse

Due to the success of the land based surveys we intend to collect more of this data next year and for the extent of the research season. It will result in a busy season for the team in 2013 but we will surely get some great data to assess the presence of whales, their behaviours, and their interactions with vessels around southern Zanzibar.

Finally, we would like to extend thanks to the community of Makunduchi for allowing us to work at the lighthouse in their village. Without their willingness to support this research, data collection from the lighthouse would not be possible!

Photographs © Zanzibar Humpback whale Project

Zanzibar Humpback Whale Research Project 2012

Distinct and beautiful songs of the male humpback whales have been making waves in Zanzibar and our research team has been able to take full advantage with some lengthy recordings using a specialised hydrophone to allow for the low frequency sounds to be picked up.

The preliminary results have been very encouraging with the majority of the songs being visible in the analysis.

When the team analyse the songs we use a specialised bioacoustics program. This allows for the song to be viewed on a graph, a spectrogram. Humpback whale songs are relatively complex but they have distinctive patterns that may be used for analysis. Each song is about 20-30 minutes long but may be repeated for several hours. The song is divided into different sections, the largest being themes. These themes can then be further broken down to smaller fragments called phrases and units.

The organisation and structure of the songs is of particular interest to Nat Stephenson (research assistant and Newcastle undergraduate student) who will be analysing the recordings for his dissertation project. Nat will be comparing the songs from this year to recordings from previous years to look for changes within season and also changes over a greater temporal span.

The songs are seen as a crucial ingredient in the mating behaviour of humpback whales and we hope that the song analysis in combination with all other data we are collecting will give us further understanding about the humpback whales off east Africa.

Nat and Kristin deploying the hydrophone to record humpback whale song.

Example of humpback whale song (dark wiggles) as shown in a spectrogram.

Photographs © Zanzibar Humpback whale Project

Zanzibar Humpback Whale Research Project 2012

Blog 7: Risso’s Dolphin Necropsy 21/07/2012

Saturday the 21^st of July was the start of Ramadhan in Zanzibar which, coupled with a rough sea, resulted in the project team enjoying a quiet day off. We used this precious down-time to get some computer based project work done and to do some washing. After a fairly relaxing morning, the team received a call from Pandu (one of our local contacts) who informed us a by-caught dolphin had been landed in our neighbouring village, Kizimkazi-Mkunguni. After quick preparations to bring the necropsy kit and data forms together we were driven straight to Mkunguni to take photos and collect samples from the dolphin.

The “dolphin” found by fishermen from Kizimkazi-Mkunguni

 However, when we arrived, to our surprise we discovered it wasn’t a bottlenose or humpback dolphin but a species we don’t normally see in the waters around southern Zanzibar. We were relieved when we found out the fishers found it dead and floating in the water meaning it was not another by-caught dolphin. At first glance, Kyla thought it might be a pygmy killer whale (Feresa attenuata) or melon-headed whale (Peponocephala electra) based on the body size, shape and colouration but we were baffled as some features, such as the very tall dorsal fin and the teeth (or lack thereof!) didn’t seem right. Of course, after sending photos to the project leader Dr Per Berggrenat Newcastle, he suggested it might be a Risso’s dolphin calf; Risso’s dolphins (Grampus griseus) are very scratched resulting in a greyish colouration but a calf/juvenile is still quite dark and Risso’s dolphins have very few teeth.

Kristin and Kyla looking for the teeth…and only finding two tiny ones at the front!

 As soon as we arrived at the fish market at the beach in Mkunguni we started taking photos, measurements and collected tissue samples of the dolphin. As mentioned above, no teeth could be seen initially; we thought it might be an older animal with very worn teeth, but on close inspection we found two very small teeth at the front of the jaw. So, a section of the jaw bone with the two teeth was removed as a sample. The cause of death was not identifiable as there were no external signs such as lacerations, or injury from fishing gear, however, the animal looked under nourished. We were not able to conduct a complete necropsy on the animal but we collected the stomach contents for possible dietary analyses.

Yunusu, a friend of the project, helping us collect samples

Members of the research team checking out the Risso’s calf with fishers from Mkunguni watching with curiosity.

One thing we didn’t think about when we collected the bucket of guts to take back with us was the smell we’d have to endure on the drive back to Kizimkazi-Dimbani! We ended up driving the entire way with back of the car open, much to the amusement of all the locals. All in all, it was a very unexpected but interesting day!

Photographs © Zanzibar Humpback whale Project

Blog 6: First whales of the season! 15/07/2012

Early Sunday morning was a very exciting day for the Zanzibar Humpback Whale Research Project team. A local fisher called us reporting two whales in the area outside Makunduchi off the southeast coast of Zanzibar. We eagerly got our equipment together, jumped into our boat and headed in the direction given by the fisher. We were hopeful to find the whales although it takes about an hour to reach Makunduchi from Kizimkazi-Dimbani. And they were! Kristin was the first to spot a blow about 1500m ahead of us. The team sprang into action, with spotters at the bow and behaviour recorders at the stern, all barely able to contain their excitement at finally seeing the first whales of the season! The whales turned out to be a mother, her calf and an escort whale travelling slowly along the south east corner of the island with beautiful tail dives providing excellent opportunities for photo ID. After an hour the whales started travelling faster and were soon too far away so we left them alone to survey for other whales.

It was during our lunch break that Kyla suddenly shouted ‘Whale!!’ She had spotted a breaching whale 2500m, directly ahead of us. Lunch was quickly packed up and replaced by cameras and other equipment. There were two adult whales and a juvenile which were socializing and resting. We followed them until we had collected enough data and then decided to leave them alone. The wind was picking up and we decided to head home, very happy with our two first whale sightings.

On the way back we decided to do some target practise with the crossbow with an old life jacket, with the intention of collecting future small biopsy samples from the whales. Skin and blubber samples will be used for genetic studies to investigate how the whales off Zanzibar are related to those found in other areas off Africa and elsewhere around the world.

Back at the house, we discussed the day’s activities over dinner. After months of preparation we had successfully conducted our first whale survey. It gave our new students Yussuf, Nat and Lynne a great opportunity to practise the data collection and to see what happens when we encounter a whale. We all went to bed happy and excited at the prospect of seeing more whales in the morning.

Zanzibar Humpback Whale Research Project 2012
Blog 5: Elevating our survey approach 13/07/2012

This year the survey methods are being broadened to increase our survey area and the type of data we collect to improve our ability to research the humpback whales off Zanzibar and East Africa. One opportunity to do this has come in the form of Makunduchi Lighthouse which provides a unique, 44m above sea level, platform from which to conduct land based survey of cetaceans and boat traffic. The lighthouse sub-team lead by Dr Per Berggren  assisted by Nat and Yussuf travelled to Makunduchi Lighthouse to calibrate the survey equipment ready for a 10 day pilot study which will start later in the season. It was incredibly hot and we soon valued the shade provided by the light housing and the bottled water we had brought.

Yussuf and Nat at the Makunduchi lighthouse 

We use mounted binoculars to allow for tracking of the whales focusing on positioning but also to study respiration rates and behaviour of the whales and how these may be altered by interactions with vessels also using the area.

The views from the lighthouse will hopefully provide the perfect area to survey the passing whales but unfortunately there were no whales to be seen during this first visit. Instead we utilised our research boat to calibrate the method to estimate distance by knowing the GPS locations of both the lighthouse and the boat and the number of binocular range reticles that this distance was equivalent to.

Yussuf calibrating the binoculars, see the boat?
We will provide an update later from 10-day lighthouse pilot study.

Photographs © Zanzibar Humpback whale Project

Zanzibar Humpback Whale Research Project 2012
Blog 4: Disentanglement and Whale watching 12/07/2012

The humpback whales in Zanzibar coastal waters are being entangled in artisanal drift and bottom set gillnets and in lines to fish traps. This is bad both for the whales that may die unless they can free themselves from the gear and for the fishers that risk losing their equipment and only source of income.

Humpback whales entangled in gillnets off Zanzibar

To address this problem and to assist in the development of sustainable whale watching as a potential new source of income to the local communities we arranged a 2-day Workshop 10-11 July 2012 at Kizimkazi-Dimbani on the south coast of Zanzibar. The Workshop built on two previous Workshops held in 2010 and 2011. The first day of the Workshop was dedicated to bycatch mitigation using “weak-links” as a possible mitigation measure which was introduced during the previous years’ Workshops and to assess the effectiveness of the disentanglement teams that was trained in 2010. The second day of the Workshop was dedicated to developing guidelines for sustainable whale watching. Each day was introduced by presentations for each Workshop topic by Dr Omar Amir (Zanzibar Ministry of Livestock and Fisheries) and Dr Per Berggren (Newcastle University) followed by discussions and recommendations from the Workshop.

Bycatch mitigation and whale watching Workshop participants

“Weak-links” make the nets break into smaller panels of nets if a whale swims into the net and can thus prevent entanglement which saves both whales and the fishers’ nets. Two “weak-link” nets were made in 2011 and have been trialled during the past year. Mr Pandu, the fisher responsible for the “weak-link” nets, reported that the nets have worked very well and had similar target fish catch as non-modified nets. No whales had been entangled in the “weak-link” nets during the trial year so it was not possible to assess their effectiveness to prevent whale entanglements. Mr Pandu still encouraged all fishers to introduce “weak-links” in their bottom set and drift gillnets. After some discussion all present fishers agreed that they would implement “weak-links” in their nets. Last year fishers were provided with the materials to make “weak-links” and arrangements were made at the Workshop for distribution of the materials.

Example of “weak-link” made using hogrings (metal clamps)
©Jamison Smith

The disentanglement teams that were trained in 2010 and 2011 respond to whales that get entangled in nets and use specialised gear provided to free whales from the nets.  The teams gave a demonstration at the Workshop of the gear and procedures for how to disentangle whales. There is currently one set of specialised gear and the disentanglement teams expressed the need for a second set so that there would be one available in the south and one in the north of the Island facilitating response in the two main fishing and likely entanglement areas. The Workshop agreed that it would be beneficial to demonstrate the use of the existing gear as an argument when seeking funds for a second set.

 
Humpback whale by catch entanglement team in action
©Jake Levenson

The second day of the Workshop was dedicated to developing guidelines for sustainable whale watching. The introductory presentations have information about current dolphin tourism in Zanzibar and plans for development of whale watching activities. Further, information was presented on whale watching in other countries and the guidelines and regulations used in e.g. Australia and USA. This information was used as a starting point for discussion and Dr. Berggren further presented suggested guidelines for whale watching that was then discussed. The socio-economy of both dolphin tourism and whale watching was discussed and how the income for the local operators could be improved. Further, the current conflict between gillnet fishers that accidentally kill dolphins as bycatch and dolphin tourism operators was also debated. It was decided that these discussions would continue and be resolved in a meeting following the Workshop.

Humpback whale watching off Zanzibar

 Overall the Workshop was very successful with participants agreeing to use “weak-links” to mitigate whale bycatch in gillnets and agreement on the need to adopt guidelines for best practice for dolphin tourism and whale watching. Dr. Amir informed the Workshop that the Ministry of Livestock and Fisheries are preparing regulations for both fisheries and tourism activities within the Menai Bay and Mnemba Island Conservation areas. The Workshop was organised jointly by the Zanzibar Ministry of Livestock and Fisheries, the Institute of Marine Sciences, University of Dar es Salaam, with support from the Zanzibar Humpback Whale Research Project, the University of Newcastle, the US National Oceanic and Atmospheric Administration (NOAA) and the International Fund for Animal Welfare (IFAW). There were over 40 participants with representation from most stakeholders including: Government, fishers and their organisations, Kizimkazi Dolphin Tourism Operators Association (KIDOTOA) and the Menai Bay Conservation Area representatives and Researchers.

Photographs © Zanzibar Humpback whale Project

Zanzibar Humpback Whale Research Project 2012

Blog 2: Lighthouse visit 07/07/2012

Just before arriving to the project, we received news that we had permission to conduct surveys from the Makunduchi lighthouse located on the southeast tip of Zanzibar Island! In addition to the vessel based surveys we would like to add a land-based component to the research this year. Land-based surveys are useful because they are less restricted by weather conditions and do not affect the data collection by disturbing the animals. Prior to initiating land-based surveys we wanted to visit the lighthouse to check if it would be suitable for binocular and theodolite surveys; if it was suitable the pilot study would be initiated over the next couple of weeks to collect additional data on humpback whale occurrence and behavior.

 The lighthouse at Makunduchi

Dr. Per, Nat and Lynne landed in the Stonetown airport, Zanzibar on the morning of Saturday July 7^th. Kristin and Kyla had arrived some days earlier and taken care of the first weekly food shopping in Stone town before meeting up with Per, Nat and Lynne at “our” house in the village Kizimkazi-Dimbani (on the southwest coast of the Island). Almost immediately after arriving to the house Juma, the owner of our house, a local friend and working partner through IMS, drove us to Makunduchi to see the lighthouse. The drive from Kizimkazi-Dimbani to Makunduchi is only 20 minutes but from the village to the lighthouse the track was not good at all; we bounced over sharp coral rag and sharp bushes scratched and squeaked along the sides of the car! We cringed with each squeak and hoped Juma’s car was not too damaged by the trip.

The lighthouse looming above us!

When we arrived we piled out of the car and looked up at a beautiful red and white (but peeling and somewhat faded!) stone lighthouse looming above us. Two local men (Mr. Abdallah and Mr. Maneno), responsible for the upkeep and maintenance of the lighthouse, were there to meet us and show us around. After a brief exchange of greetings in Swahili we were soon climbing the 165 steps to the top of the 27 m building (44 m above sea level). The climb was definitely worth it…views of the sea along the east and south coasts and the villages and low, scrubby forests of the island stretched out before us. It was quite peaceful at the top of the lighthouse with the sound of sea breezes and goats bleating in the shrubbery below.

We were keen to spot whales and immediately began scanning with our binoculars but, unfortunately for us, there were no whales this time. It is early in the season so we anticipate whales soon and after seeing the lighthouse decided it will be a feasible location for a pilot study.

Zanzibar Port Corporation sign inside the 27m lighthouse (44 m above sea level!)

Views from the top!

Nat scanning for whales

Humpback Whale Research Project

Blog 1: Touch down in paradise…the team arrives in Zanzibar!

It’s hard to believe it’s been eight months since Zanzibar Humpback Whale Research Project team last conducted surveys in the waters of southern Zanzibar but, after much anticipation and planning, the team is back in Kizimkazi-Dimbani! Most of us arrived a week ago and from the get-go have been busy, busy sorting out permits, stocking the house with food and supplies, organizing research equipment, training new team members and looking at a site for land-based surveys for a pilot study we will conduct this year. This has been a very productive week and we even completed four boat surveys. The boat surveys are conducted to study the occurrence and behaviour of the humpback whales arriving here, for breeding and mating, from the waters of the Antarctic where they spent the winter feeding!

This year’s Zanzibar Humpback Whale Research Team
(missing: Jessica and Khamis Khamis)

This year the research team consists of three returning and three new research staff and students: Kristin, will once again be the Field Principle Investigator (her fourth season!); Kyla, will be a research assistant (her second season) and will take over for Kristin when she leaves in August, and Yussuf, is returning as one of our local Zanzibarian research assistants (his second season). Yussuf graduated from the University of Dar Es Salaam last year and currently works with the Institute of Marine Sciences in Stonetown and we are very happy to have him back!  In addition to the returning staff, we welcome four new assistants for 2012 including: Nat (Nathaniel Stephenson) and Lynne Payne, two, undergraduate 3^rd year students from Newcastle University; Khamis, another Zanzibarian student from IMS; and, in mid-August, Jessica, will be joining us as a research assistant until the end of the season. In addition to the research team we will be working with our local captains, Khamis and Foum, again. Khamis has been working with the project for 15 years now and Foum 5 years and we are lucky to have them with us for another humpback whale research season!

Institute of Marine Sciences, Stonetown – One of our working partners in Zanzibar

The project’s Principle Investigator, Dr Per Berggren of Newcastle University, also arrived last week to help with project start-up, help the new students settle in and to organise and participate in a workshop on whale fisheries by-catch mitigation and development of best practice for whale watching activities at the Menai Bay Conservation Area offices here in Kizimkazi-Dimbani. The workshop ran for two days and included presentations and discussion on increasing the use of weak links on fishing nets (to reduce whale by-catch), developing a commercial whale watch industry in addition to dolphin watching, and the development of regulations for both whale and dolphin watching activities. Overall, Per was very pleased with the workshop and felt the issues discussed were heading in a positive direction.

Participants in the humpback whale workshop at the Menai Bay Centre, Kizimkazi-Dimbani

The beautiful beach at Kizimkazi-Dimbani – our home away from home!