Field Blog

North West Cape Dolphin Project

  • Better late than never! by Tim Hunt
    in North West Cape Dolphin Project
    31 Dec 2014  | 0 Comments

     

     


    Better late than never! 

     

    Australian humpback dolphins (Sousa sahulensis) of the North West Cape, Western Australia

     

    The 2014 field season of the North West Cape Dolphin Research Project (NWCDRP) finished up at the end of October 2014, and as with 2013, a very successful season it was indeed. Team Sousa kicked off fieldwork on 9th April 2014 and finished up on 27th October 2014, logging a total of 288 dolphins sightings over 94 survey days (533 hours on water). Our target species, the recently described endemic Australian humpback dolphin, Sousa sahulensis, was frequently sighted, and as seen in 2013, in regular mixed species associations with sympatric Indo-Pacific bottlenose dolphins (Tursiops aduncus). Interestingly, 2014 yielded more humpback dolphin school sightings than bottlenose dolphin school sightings (168 vs. 140 in 2014 compared to 109 vs. 163 in 2013, humpback and bottlenose respectively). 2014 saw numerous resights of the same individuals sighted in 2013, with some new individuals being added to the photo-identification catalogue. As of the end of 2014, there are just over 100 individual humpback dolphins identified, and just over 250 individual bottlenose dolphins identified within the North West Cape study area. With the high re-sighting rates of some individuals in both 2013 and 2014 field seasons, preliminary evidence suggests there is certainly a degree of residency of both species to the study area. I, Tim Hunt, CEBEL PhD Candidate will be spending 2015 in the office at Flinders University analysing both field seasons of data, not only determining abundance, residency and site fidelity, but also habitat use and social structure of Australian humpback dolphins around the North West Cape. Plenty of data to keep me busy!


    Dolphin sightings for 2014 field season of the North West Cape Dolphin Research Project. Total of 288 sightings over 94 survey days (533 hours on water) between 9th April and 27th October 2014

     

    The NWCDRP would certainly not be possible without the volunteer field assistants, who come from all over the globe to gain experience in marine mammal research and further their skills in the field. In no particular order, I would like to shout out a HUGE HUGE thankyou to 2014 Team Sousa members Victoria Pouey-Santalou (France), John Symons (USA), Kate Indeck (USA), Gabi Kowalski (Germany), Kaja Wierucka (Poland), Vicky Stein (USA), Natalie Ashford-Hodges (UK) and Cindy Van Schie (Holland) for their very hard work this field season. We had a lot of fun, a lot of laughs, and some absolutely amazing animal encounters, including killer whales, false killer whales, humpback whales, manta rays, tiger sharks, hammerhead sharks, dwarf minke whales, swarms of schooling fish, flying fish, and plenty of sea turtles, seas snakes and emus. Let’s not also forget all those amazing push-ups ;-). Thanks to all my supervisors for their guidance and support this field season, especially to Dr Guido Parra for coming to Exmouth, imparting his wisdom and showing me the ‘biopsy rifle ropes’. Collecting dolphin skin samples using a PAXARMS biopsy rifle was an element of data collection introduced half way through the 2014 field season, and all samples collected this season and coming seasons will help give insight into population social and genetic structure in the region. Thanks also to honorary Team Sousa members David “Papa” Hunt, Karl Beerenfenger, Daniella Hanf, and all others that came out on the water with us and helped out. I want to give special thanks to my wife Janine and baby daughter Amelia for moving up to Exmouth and supporting me through this field season. It was fantastic to have my girls to come home to at the end of each day. 

     

     

    Members of Team Sousa 2014

     

    Thanks must also go to the Exmouth community, local businesses and local government departments for their support and interest again this field season. The sense of community pride and conservation is very strong in Exmouth, and what you have is truly something special and unique. I had amazing turnouts to the community presentations this season so thank you Exmouth for your interest and support. Special thanks to Cape Conservation Group for their continued support, John Totterdell (MIRG Australia) and NOAA Southwest Fisheries for their contributions of dolphin sightings, and to staff from the tourism industry that contributed dolphin sighting information. Thanks to the Murdoch University Coral Bay Research Station for the use of their boat and vehicle, and to our funding bodies, the Australian Government’s Australian Marine Mammal Centre, and the Winifred Violet Scott Charitable Trust, whom without this research would not be possible. To everyone else that has been involved in the NWCDRP in 2014, thankyou thankyou thankyou.

    As we progress into 2015, plans are being finalised for the 2015 field season of the NWCDRP. Keep your eye on the CEBEL Facebook site (www.facebook.com/CEBELresearch) for updates of this project and for more photos of the 2014 field season and Team Sousa’s adventures on the World Heritage Listed Ningaloo Coast. Sadly, I won’t be back for a full season in 2015 as I must submerse myself in the data collected over 2013 and 2014 and write my PhD thesis. However, I will be aiming for publications this year so keep your eyes out on the CEBEL website and Facebook site for results of humpback dolphin research on the North West Cape. Farewell Exmouth, it’s been an absolute pleasure and I will miss you. I very much hope to continue conservation work in the beautiful part of the world post PhD in 2016.

     

    CEBEL PhD Candidate Tim Hunt with the trusty ‘Sousa’ research vessel

  • Team Sousa wraps up the first field season by Tim Hunt
    in North West Cape Dolphin Project
    24 Jan 2014  | 1 Comment

     

     


    Team Sousa wraps up the first field season!

     

    A “smiling” Sousa

    Well, the first field season for the North West Cape Dolphin Research Project has sadly come to a close (ended 30th October), and what an absolute cracker of a season it has been! Since the last field blog entry in early August the weather has been much more co-operative and we’ve managed to get out on the water a great deal more than the first half of the season. For this first field season we’ve had a total of 84 days (423 hours) on water and over 260 dolphin school sightings, with dolphins sighted on 95% of the days we got on water. That’s an extremely good sighting rate in anyone’s books! We’ve clocked up over 3700 km on water and identified over 200 different individuals so far (both humpback and bottlenose dolphins combined), so it’s fair to say Team Sousa has been very busy with lots of dolphins, and lots of other amazing marine wildlife here at Ningaloo!

     

    2013 field season preliminary results for the North West Cape Dolphin Research Project. Left: all vessel track data (totalling 3711 km). Right: a total of 266 dolphin sightings over 84 days (423 hours) on water.

     

    Since August, Team Sousa underwent some personnel changes. We sadly farewelled our resident maple leaf Katy Gavrilchuk and resident South Floridian Lauren Connor, both of whom had been with us from the beginning of the season and instrumental in the development of field protocols. I thank you Lauren and Katy for your assistance (and patience) with this project as it developed, and for bringing good fun times to hours on the water. You are welcome back anytime and I wish you all the best for your future endeavours. With Katy and Lauren’s departure we saw the arrival of English twitcher Mel Froude (a marine mammal and bird enthusiast), Italian cooking extraordinaire (from Italy in fact!) Micol Montagna, and regular sea lubber Englishman Rob Watson. All three were a fantastic addition to Team Sousa and over the past couple of months and we worked really well together and saw some amazing sights on Ningaloo (see below).  I’d also like to thank my lovely wife Janine Hunt and father David Hunt for helping out on the boat while they were up here visiting in the middle of this season. I’ll make marine biologists out of them yet! This research could not happen without the help of volunteers so I want to publicly thank all Team Sousa members past and present for making this first field season such a success! See below some Team Sousa testimonials from their experience on the project:

    Lauren Connor (Florida, USA):

    “My experience working on the North West Cape Dolphin Research Project (a.k.a Team Sousa), was an amazing experience and a fantastic opportunity to work in paradise! Working on Ningaloo reef is unlike any other place in the world, and my co-workers were just as spectacular! Every day spent on or off the water was a new adventure. Whether we were observing a mixed group of twenty something dolphins, or watching humpback whales breach off in the distance, working here is an invaluable experience for any marine biologist!"

    Katy Gavrilchuk (Québec, CANADA):

    “Participating in the North West Cape Dolphin Research Project was a great and unique research experience in a beautiful part of the world. It was gratifying to contribute to the initial stages of this potentially long-term project, which holds important conservation implications for the local cetacean populations. The field work involved a combination of techniques (vessel navigation and dolphin approaches, photo-identification, detailed behavioural sampling), efficient team work and some pretty spectacular encounters.”

    Rob Watson (Isle of Wight, UK):

    “Wow, where do I begin? For me, this was an incredible two months working on the stunning Ningaloo Reef. The amount of research and boat driving experience I gained from this trip was extremely valuable towards my future career prospects. It seemed that every day when we were on the water looking for dolphins, we saw something that made me shout "woah", then we looked at one other with our mouths wide open. If you love Manta Rays, Dugongs, Humpback Whales, Sharks, Flying Fish, Sea Snakes, Bottlenose Dolphins and OF COURSE Humpback Dolphins, you are gunna love this place.”

    Melanie Froude (Hastings, UK):

    "Without wanting to sound like a holiday brochure, Ningaloo Reef really is a paradise. The diversity and abundance of wildlife is unbelievable, every time we thought we had seen it all, something else new would suddenly pop up beside the boat to surprise us! It is honestly one of the most amazing places I have ever been and I feel so privileged to have had the opportunity to work there. This is an important and exciting new project to be involved in; the Sousa always proving to be an intriguing species. An added bonus would be the community spirit of Exmouth, the sun and warmth, and, of course, being a part of the awesome ‘Team Sousa’!!"

    Micol Montagna (Milan, ITALY):

    “My experience on the North West Cape Dolphin Research Project definitely exceeded all expectations, and I felt I learnt a lot. As this is a “live in” position, I felt myself completely involved in the project and all that is related to it. I felt I got a better understanding of the whole program itself, not to mention the Ningaloo Reef area, as there is such an amazing variety of marine wildlife and it is possible to get in contact with many other researchers conducting their studies there. Furthermore, I would say that this interaction with other researchers gave the place a really stimulating atmosphere, and it makes it possible to learn more about different fields, create contacts and get knowledge about different organisations. I really appreciated how the research assistant’s duties have been organized, meaning I could improve my skills in all the different tasks the project involves; either in the field (getting more confident in all the photo ID techniques, swapping the roles every day with the other team members) or in data entering and analysing. I felt it was a really intense and satisfying experience, and also a unique experience to live so close to such a wonderful marine life and environment. "

     

     

    Team Sousa on a break at Mandu Mandu Gorge, Cape Range National Park (Ningaloo Reef in the background)

    (Left - Tim, Katy & Lauren; Right – Rob, Mel, Micol & Tim)

     

     

    Team Sousa hard at work on Ningaloo Reef.

    Dolphin sightings

    As we continued our transect surveys to systematically search for dolphins we got to know the various areas of the North West Cape and the animals that seem to be “regular” to those areas. With ~95% of humpback dolphin sightings analysed thus far we’ve identified over 80 individual humpback dolphins (excluding calves) in waters around the North West Cape. We’ve identified over 100 individual bottlenose dolphins, and that’s with only ~50% of sightings analysed, so it’s safe to say that we will have a lot more individuals in the catalogue once they have all been processed! Of all our humpback dolphin sightings, almost a third have been in mixed groups with bottlenose dolphins. The behavioural interactions between the two species is very interesting to observe, much ‘socialising’ goes on so it will be interesting to look at these sightings over the summer back at the CEBEL office at Flinders Uni and see if it’s the same individuals that are being sighted together. Nevertheless, mixed sightings certainly make for great Sousa photos!

     

    Socialising Sousa on the North West Cape.

    Typically, humpback dolphins don’t surface too close the boat and are often difficult to approach closely to get photos (hence a 400mm zoom lens on my camera!). They almost never bow ride the boat and in a second they can be gone never to be seen again! You’re probably asking yourself why on earth I’m doing my PhD on somewhat elusive animals? Well, information available on these animals in WA is scarce and there is not information available to conduct a proper conservation status assessment. So, the only way to build knowledge is to be out there on the water, and when Sousa are spotted, we must approach very slowly, patiently, and cautiously and trust that on at least one surfacing the animals will be close enough to get a decent dorsal fin photo. You win some and you lose some, but that’s the nature of fieldwork. With bottlenose dolphins however, it’s a very different story. This species will go about their daily behaviours as if we weren’t there. They will in fact regularly surface right next to our research vessel and often bow ride. Bottlenose dolphins do make for great photos and we’ve managed to capture some pretty nice shots throughout the season (see photos below).

     

    Boisterous bottlenose dolphins of the North West Cape.

    Safety on the water

    One thing to remember when conducting marine fieldwork - the ocean is the master. Early one morning while conducting transects Team Sousa came across a small capsized vessel on the edge of Ningaloo Reef. We immediately searched the general area for survivors and radioed the authorities. We were advised that a vessel had capsized the afternoon of the day before and that both persons on board had been rescued. However, we radioed through the boat registration to confirm this was in fact the same vessel and a response a number of minutes later advised this was the same vessel. We were less than a couple of miles from the Tantabiddi Boat Ramp so advised authorities we would tow the vessel back to land to be retrieved. Three quarters of the way to the boat ramp the towed vessel took on too much water that it was very difficult to tow any further against the outgoing tide so we navigated directly inshore and took it to the beach. Here we were able to use the small waves rolling in to overturn the vessel the right way up. From there we were easily able to tow the boat back to the boat ramp where the extremely grateful owners (read capsize survivors) met us and we winched their boat on to their trailer. The vessel owners shared with us that they were on the edge of the reef and a couple of sets of rolling waves came in that they could not navigate away from and subsequently their boat was flipped. They were in the water for about two hours before someone came to get them, and although not far from shore where they capsized, it was still far enough that with tides and currents, they weren’t able to make much way and get to the beach. Apart from a few minor fractures, bruises and pretty bad sunburn, they were thankfully ok.

    Seeing this capsized vessel really brought home the message that the ocean can be a dangerous place and that a large rolling swell means waves can break out of nowhere and put vessels at risk. I’m fortunate that I’ve had experience driving boats in coastal waters here in Australia, Canada and Fiji but no matter how much experience a skipper has, the ocean is, and always will be, the master.

     

    Team Sousa boat salvage operation: We radio the capsized vessel in to authorities, tow it to shore and then flip it upright to then be towed to the boat ramp and retrieved by the owners.

    “Whale soup”

    The North West Cape during the months of July-October is, for lack of a better term, whale soup. In July we witnessed what we believe was an immediate post birth of a humpback whale calf. There was splashing off in the distance and as we got closer we could see very small pectoral fins flailing about at the front of an adult. We sighted soo many very small calves with mothers during July/August that it’s likely these animals were less than a few weeks old. It’s possible given the humpback whale population in Western Australia that a number of births are occurring in areas not previously documented before. We had humpback whales on a few occasions breach out of nowhere and scare the begeezuz out of us, the closest being ~20m from the research vessel! Just incredible! During September/October on the Exmouth Gulf side we were literally dodging whales while we were conducting our line transect surveys. Exmouth Gulf is a resting ground for humpback whales and where our transect lines are located is the thoroughfare for mother/calf pairs and escorts as they exit the Gulf around the tip of the NWC and head south to their summer Antarctic feeding grounds. Humpback whale calves appear quite inquisitive and on two separate occasions while with a group of ~20 bottlenose dolphins we were buzzed by a humpback calf that swam right alongside our vessel while mum kept a close watch (see photos). It’s moments like those that you pinch yourself as you can’t believe what you’ve just witnessed.  

     

    Exiting the NWC: A pod of humpback whales ‘making haste’ (top) and what looks like “lochness whale” (bottom).

    An incredible diversity of marine life on the NWC

    In addition to humpback whales, the manta ray and sea turtle sightings appeared to increase the last few months of the field season (August-October). At one point we saw six manta rays together in one single location in the Exmouth Gulf! For turtles the increase in numbers was expected given this time of year it’s turtle mating season, but it often threw us off as you would see an object at the surface of the water which, from a distance, looks like a dorsal fin, when in fact it was turtles on top of each other doing as nature best intended. In late October on the night of the full moon we went to a beach on the tip of the NWC in the hope of seeing turtles nesting. None of us had seen it before and immediately upon arriving at the beach we were all extremely lucky enough to be able to witness not one, but three green turtles come up the beach, dig their nests then lay their eggs. Again, just incredible!

     

    Manta rays of the North West Cape.

                 

     

    Green sea turtles of the North West Cape.

     If dolphins, whales, manta rays and sea turtles aren’t enough marine diversity to tickle your fancy, then fear not, the NWC has got a lot more to offer. We were constantly surprised but what we could come across while looking for dolphins. We were fortunate enough to see sea snakes (say that 10 times really fast!), a leopard shark, a bow mouth guitar fish, shovel-nosed rays, eagle rays, tuna, kingfish and of course plenty of reef fish. Above the water we saw a variety of bird life including shearwaters, ospreys, sea eagles, brown falcons, pelicans, ibises, crested terns, herons, and gulls.

    On the last week of the field season we actually came across a lone whale shark just on the outside edge of Ningaloo Reef. Whale shark season officially ends in August and some tours still run into September, so for us to see a whale shark sighted from a boat (tour operators use spotter planes) in late October is, as best put, extremely bloody lucky! The 6m whale shark didn’t stick around for long, but came right by our boat and we managed to snap a nice pic of it with the GoPro. So in summary, if there’s marine species that can be found in tropical waters, the NWC has probably got it! I’ll say it again, this place is truly amazing.

     

    You never know what marine life you may come across on the North West Cape: Bow mouth guitarfish (top left); crab, species unknown (top middle); leopard shark; (top right); spotted eagle ray (bottom left); olive-headed sea snake (middle bottom); shovel-nosed ray (bottom right).

     

     

    Whale shark on Ningaloo Reef (sighted late October 2013).

     So we’ve got our marine creatures that we regularly observe when out on the water, and then we have their terrestrial counterparts, namely kangaroos and emus. We regularly sight roos and emus on our way to/from the boat ramps, and sometimes you even have to stop on the road to let a family of emus pass by! If you ever get to Exmouth you’ll notice the emu signs on the edges of town. It’s not rare to see an emu cruising on the edge of the road around the township of Exmouth! If you’re on the road at night, I can GUARANTEE you will see kangaroos. The buggers are everywhere!

     

    Emus and red kangaroos are a plenty on the North West Cape.

    Team Sousa wrapped up the field season with a few reconnaissance trips south of the study area on both the Ningaloo and Gulf sides. Both species of dolphin were sighted, new individuals in fact, so it is hoped that in the 2014 season we will be able to run some transects outside the immediate study area and help make our population estimate of the North West Cape more robust at the end of next season. I gave a community presentation at Exmouth High School just before leaving and was well attended and received by locals. I would like to personally thank everyone who attended that presentation, and extend a thank you to the people of the Exmouth region. The township of Exmouth is a vibrant community and I feel privileged to be able to call it home for 6 months of the year. I’ve been made to feel very welcome and I look forward to continue in engaging with groups such as the Department of Parks and Wildlife, Cape Conservation Group, MIRG Australia, local tour operators and other community groups. The information obtained from this research is to better help inform the conservation and management of what is only recently being described as a new, as yet un-named Australian species of humpback dolphin. A paper came out last month explaining that the humpback dolphins found in Australian waters are in fact genetically and morphologically different from those found in the Indo-Pacific region and other parts of the world (see a news article at the following link: http://www.australiangeographic.com.au/journal/new-humpback-dolphin-discovered-off-australia.htm. So essentially we’re looking at a new and potentially endemic species of dolphin in Australia for which little is known of their life history or population status, particularly in WA waters. This goes to show that the North West Cape Dolphin Research Project is now of even greater importance in building the science to understand more about Australian humpback dolphins and in order to better inform their conservation and management.

     

    PhD student Tim Hunt sharing information of the 2013 field season to the community at Exmouth High School.

    Many photos of the incredible diversity and landscape were taken throughout the field season, all of which unfortunately cannot be shared in this blog. To see more photos of the wonder that is Ningaloo and our experiences on the North West Cape Dolphin Research Project (NWCDRP) please ‘Like’ the CEBEL Facebook Page at www.facebook.com/CEBELresearch and check out the NWCDRP album, as well as other albums from research conducted by CEBEL.

    Well, that’s it for 2013. It’s been an absolutely incredible experience and what I would deem a very successful first field season. Now to firmly plant myself in the office back at Flinders Uni, look at all this data, do some analyses and plan for the 2014 field season. Team Sousa will be back in Exmouth in early April 2014 for another six month field season and we certainly look forward to bringing you more photos and interesting observations of dolphins (and other marine life!) on the wonder that is the North West Cape and the spectacular World-Heritage listed Ningaloo Reef and Cape Range National Park.

     

    Team Sousa farewells Exmouth. See you again in 2014!

     

  • The North West Cape Dolphin Research Project by Tim Hunt
    in North West Cape Dolphin Project
    18 Aug 2013  | 1 Comment

     

     


    A windy start to the first field season

    An Australian humpback dolphin (Sousa chinensis) at Ningaloo Reef

     The North West Cape Dolphin Research Project (NWCDRP) has begun, kicking off a couple of months ago in late May 2013. The aim of the project over the coming years is to determine the population size, habitat use and social structure of Australian humpback dolphins (Sousa chinensis) around the North West Cape, Western Australia. The dolphin research team (aka “Team Sousa”) is based here in Exmouth, Western Australia for the winter months (May-October), exploring the inshore waters of the World Heritage Listed Ningaloo Marine Park and Exmouth Gulf around the tip of the North West Cape. Very little is known about humpback dolphins in Western Australia and as such there is not enough information available to properly assess the conservation status of the species. From the small amount we do know about the species in Australia, it appears that humpback dolphins live in small, geographically and genetically isolated populations of 50-100 animals in shallow, tropical coastal environments (<15 m water depth). These factors, along with a low reproductive rate (calves born only every few years) suggest that this species is vulnerable to localised impacts such as coastal development, and therefore localised extinction from an area is a real possibility if not managed properly. Information gathered on humpback dolphins (and bottlenose dolphins) during this project is important given it will help inform the conservation and management of this data poor species in waters around the North West Cape from potential current and future impacts, and aid in a better understanding of the species in Western Australia and nationally.

    Study area for the NWCDRP – the inshore waters around the tip of North West Cape

    [Map images courtesy of Google Images & Google Earth]

    The NWCDRP is led by Dr. Guido J. Parra at the Cetacean Ecology, Behaviour and Evolution Lab (CEBEL) Flinders University, South Australia. CEBEL PhD Candidate Tim Hunt is the primary researcher on the project. Also involved in the project and supervising Tim are Associate Professor Lars Bejder and Mr Simon Allen from the Murdoch University Cetacean Research Unit (MUCRU), Western Australia. The project is funded by the Australian Marine Mammal Centre Grants Scheme and supported by the Western Australian Government Department of Parks and Wildlife (formerly Department of Environment and Conservation).

    Since arriving in May the weather and the winds in the Exmouth region have been ‘abnormal’ to say the least. In order to conduct dolphin surveys it is preferable if the wind is 10 knots (18 km/h) or less, and a sea state without white caps. Any windier than this and it becomes quite difficult to spot dolphins. Even if you were to see dolphins it’s quite tricky to photograph them with the boat bouncing around, and you of course risk getting your camera splashed with seawater. Digital camera equipment and salt do not mix! The two months we’ve been here we’ve had a couple of storms and experienced almost 200mm of rain. This doesn’t sound like much, but considering the region we’re in is relatively dry for the tropics, it’s still technically the ‘dry season’ (i.e. non-cyclone season) and the average annual rainfall of Exmouth is less than 300mm, I think ‘abnormal’ is an appropriate word to describe the weather here of late! Wind over the past couple of months has averaged well above 10 knots and as such we’ve had a number of days off in a row off the water. Nonetheless, although it has been an unusually windy start to the field season, the days we have managed to get out we’ve seen dolphins every time, and there are certainly plenty about which makes for lots of data and solid research.

    In order to collect data and systematically cover the study area, we have 2 x 93km transect lines that zig zag their way from Exmouth, north around the tip and south to Mangrove Bay on the Ningaloo Reef side of the Cape. As we travel along these transects at slow speed (~10 km/h) we search for dolphins.

    Study area outlining transects (red and blue lines), water depth contours, and boat ramps in the area (i.e. Exmouth, Bundegi and Tantabiddi). [Map produced with GARMIN Homeport Software]

    When we spot dolphins we observe behaviour, record group size and composition (i.e. number of adults, juveniles and calves,) take photographs of their dorsal fins (in order to identify each individual), and record environmental variables (i.e. water depth, water temperature, salinity, pH, and turbidity) in the area the dolphins are sighted and throughout the study area. We will repeat these transects as many times as possible throughout each field season (May-Oct) in order to comprehensively cover the inshore waters of the North West Cape with the aim to determine the density and population size of dolphins in the area and how these animals are using different areas around the NWC. As indicated above, the focus species for this research project is humpback dolphins, however the region is also home to bottlenose dolphins (Tursiops aduncus) which we also collect information on. Interestingly, the two species have often been observed socialising in mixed species groups. During these events we will often observe the humpback dolphins exhibiting a behaviour that can best be described as “pirouetting” (where the animal is vertical in the water, its head and rostrum protruding from the surface and the animal will spin with its pectoral fins outstretched). It’s only the humpback dolphins that appear to be doing this while the bottlenose dolphins roll over and around the humpbacks. It certainly appears to be quite “frisky” behaviour between the two species.

    Bottlenose dolphins (front) and humpback dolphins (back) travelling together in the waters of Exmouth Gulf

    Socialising dolphins: A humpback dolphin (left) and a bottlenose dolphin (right)

     

    A bottlenose dolphin rolling over a humpback dolphin

    A “pirouetting” humpback dolphin 

     Since commencing dolphin surveys on 23 May 2013, Team Sousa have been on the water 23 days (or part thereof due to windy weather). An identification catalogue for each species of dolphin sighted within the study area has been developed and to date, a total of 43 humpback dolphins have been identified (not including calves). A large proportion of these animals have been sighted more than once on separate days, suggesting there is a degree of residency of the dolphins to the NWC. Over 50 bottlenose dolphins have been identified thus far (not including calves), a large proportion of which have also been sighted more than once on separate days, again suggesting a degree of residency in the area. These findings are of course only preliminary, but over time as we collect more data throughout this field season and the coming field seasons, we will be able to work out how many animals are regularly sighted and thus determine population size. We can also work out which animals appear to associate with each other on a more than regular basis, and then by collecting genetic material in addition to photographic material, we will be able to paint a picture as to the social structure of the dolphins in the area (i.e. are those groups travelling together related, what is the sex of the individuals that are regularly seen together etc). Social structure in bottlenose dolphins is quite well studied and understood, but in the case of humpback dolphins, this is something that has not been well studied.

    Team Sousa work hard both on and off the water. If the weather is good we can sometimes be out all day on the water (7am-5pm), in the heat, constantly on the lookout for dolphins and regularly collecting data. We have to work together as a team and communicate well in order for things to run smoothly when out on the water. A full day’s worth of data sheets and photographs means almost as long in the ‘office’ downloading and entering data onto the computer, and processing photos ready for matching. In addition to data entering and processing, all the equipment needs to be cleaned, boat fuelled and rinsed, and food prepped ready for the next day of fieldwork. Field work is quite involved, but very rewarding when you’re out there on the water studying dolphins, knowing that the information you are collecting will be used to better understand the species and used to better inform their conservation and management, particularly in an area with the potential to undergo increased development and exploration in the near future.

    Team Sousa hard at work!

     Team Sousa is of an international flavour, and to date has consisted of Tim Hunt (Australia), Dr. Guido Parra (Australia via Colombia), Katharina Peters (Australia via Germany), Lauren Connor (USA) and Katy Gavrilchuk (Canada). Tim would very much like to thank Team Sousa thus far for their efforts both on and off the water in getting this project ‘fine-tuned’ and running smoothly.

    Conducting fieldwork in the waters of the World-Heritage Listed Ningaloo Marine Park, with the red cliffs of Cape Range National Park as a backdrop is, for lack of a better word, amazing. There are more than just dolphins in this beautiful part of the world, and we’ve managed to capture a few snapshots of humpback whales, manta rays, marine turtles, dugongs, and even a whale shark. Our GoPro3 has certainly been put to work under the water and we’ve been fortunate enough to capture images of these wondrous animals as they go about their daily business under the surfaces of this picturesque turquoise ocean.

    A humpback whale surfacing at Ningaloo Reef, with the edge of the reef and the backdrop of Cape Range National Park in the background

    A giant manta ray feeding at the surface

    “Frolicking” green turtles

    Underwater photos of a dugong (left) and bottlenose dolphin (right) as they swam by the research vessel.

    [NB. These photos were taken using a GoPro3 camera attached to a pole]

    Team Sousa would like to thank the staff at the Department of Parks and Wildlife (DPaW) - Exmouth Office (formerly Department of Environment and Conservation or DEC) for their support this field season thus far. DPaW have shared their knowledge of the area which was imperative in finalising our transect lines. Their marine mammal sighting data has also given us an insight to areas for possible future investigation outside our current study site. Team Sousa would also like to thank John Totterdell (MIRG Australia) and the research team from the NOAA Southwest Fisheries Science Centre USA (Robert Pitman, Lisa Ballance and Holly Fearnbach) for sharing their dolphin sighting information with us while they were in Exmouth over the past month searching for killer whales off the Ningaloo Coast. Unfortunately we can’t be everywhere at once so getting dolphin sighting information in areas where we are not is extremely valuable.

    Team Sousa is very keen to engage with local tourism operators, businesses, conservation and community groups. If you live in the Exmouth region Tim will be giving a couple of presentations on the dolphin research during the month of August (details below) and will also be providing details on how people can get involved in this research simply by reporting dolphin sightings using their smart phone and an app called ‘Coastal Walkabout’. Presentation details are as follows:

    -          5pm Friday August 9th as part of the Australian Institute of Marine Science (AIMS) Open Day and 2nd Ningaloo Marine Research Exposition. Presentations start from 5pm at the Exmouth Game Fishing Club (at the Exmouth Marina).

    -          6:30pm Tuesday 13th August at the monthly Cape Conservation Group meeting in the Science Room of Exmouth High School. All welcome.

    That pretty much wraps up the first blog for this season. The team is certainly hoping for an improvement in the weather for the next three months and is very much looking forward to some great days on the water in this beautiful part of Australia. It is anticipated a blog will be posted once a month, so expect a few stories and a lot more pictures from our experiences around the North West Cape.

    Now let’s go find some dolphins! See you on the water!

     

                  

     

 
 

Cebel

School of Biological Sciences, Flinders University

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