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 season change from winter to spring. 

Duke University Chapel and campus squirrels

North American Wood duck and Canada goose at Duke

The daffodils and cherry blossoms bloomed in 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.

The study area with transect lines around the city of Bunbury, south west Australia.

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.

“Lunchbox’s” calf , “Chippy”, with a peanut head which is a sign of poor body condition.

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”.

“Shredder’s” calf, “Splinter”, with a shark bite.

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.

“Mrs Iruka” and her calf “Dori” approaching the research vessel

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.

My final field season saw the monthly intensive boat-based photo-identification surveys come to an end after two years of data collection. We now concentrate our efforts on collecting theodolite tracking data in both Kealakekua Bay and Kauhako Bay, increasing our focal follow data and continuing to collect more bioacoustic data from our bottom-mounted loggers.

Theodolite
A theodolite is a surveyors instrument that, when used with a laptop computer running the program Pythagoras, can be used to determine the GPS coordinates of spinner dolphin groups, vessels and swimmers in the bays from land. Every five minutes we record the position of the dolphin group within the bay and the computer saves this information, along with behavioural data, to a database. We can then use these data to determine the movement and behavioural patterns of the dolphin group within the bay. In addition, every 10 minutes, we also record the position of swimmers, kayaks, stand-up paddle boards and boats within 300 m of focal dolphin group.

Kealakekua Bay
To get to our theodolite station in Kealakekua Bay we walk down the path leading to the the Captain Cook monument. It takes about 40 minutes to walk to the theodolite station, however this GOPRO video is speeded up 10X and is a little shorter:
Up until January 2013, we have collected 189 hours of spinner dolphin theodolite tracks in Kealakekua Bay with an average track length of 8 hours 20 minutes. However, this does not include the numerous hours we’ve waited on the cliff top for the dolphins when they didn’t enter they bay.

From 2nd January 2013 the Department of Land and Natural Resources (DLNR) in Hawaii began new management action for Kealakekua Bay by placing a moratorium on kayaks and some other vessels until March 31st 2013. This provided us with the opportunity to collect land based movement and behavioural data on the spinner dolphin groups in Kealakekua Bay with reduced interactions, mainly from kayaks. This 35 second GOPRO time-lapse video shows a day in the life of Kealakekua Bay from the theodolite station, one frame taken every minute over a period of 9 hours 30 mins.

Recently the humpback whales (Megaptera novaeangliae) have migrated from Alaskan waters to the Hawaiian Islands to breed. From our theodolite station we have seen a number of humpback whales in the bay with some spectacular breaching.

Humpback whale (Megaptera novaeangliae) breaching in Kealakekua Bay

Humpback mother and calf below our theodolite station in Kealakekua Bay

Focal Follows
We continue to collect boat-based behavioural and human interaction data from our group focal follows. Leaving Honokohau Harbour, we head north until we encounter a group of spinner dolphins. We then photograph the dorsal fins of the group and then begin collecting behavioural and human interaction data. These data will allow us to provide details on the human interactions on spinner dolphins outside their resting bays. During our group focal follows we have seen some of the individuals that we recognise from photographing them in the resting bays, e.g. Mascot, who we have photographed in Kauhako, Honaunau, Kealakekua and Makako Bays.

Mascot north of Honokohau Harbour

We have seen some individuals with fresh scarring from fishing line and hooks.

Fishing line injury

Fishing hook injury

In addition we have seen spinner dolphins, bottlenose dolphins (Tursiops truncatus) and pantropical spotted dolphins (Stenella attenuata) interacting on a number of occasions.

Pantropical spotted dolphin (Stenella attenuata)

Bottlenose dolphin (Tursiops truncatus) and spinner dolphin (Stenella longirostris)

Acoustic Loggers
This field season we removed two of our bottom mounted acoustic loggers from Honaunau Bay and Makako Bay. However, we are still collecting bioacoustic data from our bottom-mounted acoustic loggers in Kealakekua Bay and Kauhako Bay. Since the loggers were deployed in 2010 we have collected over 4Tb (Terrabytes) of bioacoustic data. Using these data in combination with the theodolite data we will be looking at the types of sounds the spinner dolphins make in different behavioural states. This, in turn, may tell us if the dolphins are being disturbed during human interactions. For example, Ken Norris, who began researching Hawaiian spinner dolphins in the 70s and 80s hypothesized that during rest, the spinner dolphins were acoustically silent.

While we have been collecting our acoustic data we came across a group of pygmy killer whales (Feresa attenuata) just north of Kauhako Bay.

Pygmy killer whales (Feresa attenuata)

A little bit of sad news:

The Hawaiian monk seal (Monachus schauinslandi) is one of the rarest marine mammals in the world. As a consequence it is listed as endangered under the endangered species act and on the ICUN Red List. A juvenile male Hawaiian monk seal K68/69, was found lying on a northern beach with breathing difficulties. Alex Abe, one of my volunteers and I, helped the local Marine Mammal Response Network to capture the seal and transport it to the local NOAA office in preparation for a flight to Oahu for treatment. Unfortunately, the young seal had ingested a fishing hook and didn’t survive surgery.

K68/69 juveniile Hawaiian monk seal (Monachus schauinslandi) injured from ingesting a fishing hook

Supervisors
Finally, in early December three of my supervisors, Ken Pollock, Dave Johnston and Lars Bejder paid a visit to Kona. We went out on the boat and saw spinner dolphins in Kealakekua Bay and Makako Bay, in addition to a humpback whale traveling north past Kailua Bay. It was a very productive visit as we were able to sit down and thrash out our initial spinner dolphin abundance estimate paper, which we hope to present at the Pacific SRG meeting in San Diego from April 2-4 2013 and to submit for publication very soon.

It wasn’t all work though…

Ken, Hawaiian shirt and mai tai

Dave and his beer

Lars, Hawaiian shirt and mai tai

Assistance and assistants
I would like to say a big thank you to Justin Viezbicke, Hawaii Island Programs Coordinator for the loan of the theodolite and tripod, to Chris Gabriel, Susan Rickards and Suzanne Yin of the Hawaiian Marine Mammal Consortium for the loan of their thodolite tripod and to McCandless Ranch for letting us setup out theodolite on their land.

And, by no means least, all my assistants that have helped me out during this field season Bob Gladden, Tasha Boerst, Amy Brossard, Nicole Penkowski, Laura Bray, Virginie Wyss, Lonneke Ijsseldijk, Daniella Hanf, Dan Hazel, Laura Cunningham, Sophia Gelibter, Audrey Archer, Stephanie Petrus, Katrina Nikolich, Mariel ten Doeschate, Brigid McKenna, Rosie Blackburn, Alexandrea Abe, Laura McCue, Tory Johnson and Becky Ingram.

The Coastal and Estuarine Dolphin Project (CEDP) collects photo-identification, behavioural, and longitudinal data to support the long-term conservation of bottlenose dolphins in metropolitan waters of Perth, Western Australia.

The beggars

The illegal feeding of dolphins is a key conservation issue for dolphins in the Perth area. Finn et al. (2008) reported 14 dolphins resident in Cockburn Sound exhibiting behaviours indicative of being conditioned to human interaction by food reinforcement (e.g., approaching and remaining in close proximity to the research boat). Analysis of scarring rates found that dolphins that interacted with humans for food (i.e., “beggars”) are at greater risk of entanglement and boat strikes than other dolphins (Donaldson et al. 2010). Donaldson et al. (2012) also found that social learning influenced whether dolphins learned to interact  with humans for food, particularly among male associates.

In our winter 2012 season, the adult male Backpack – not previously known as a beggar – has approached close our research boat on three different occasions (once in Cockburn Sound and twice in the Swan Canning Riverpark).

Backpack is an old male (first seen in 1993), resident in Cockburn Sound and recently observed up to Freshwater Bay in the Swan Canning Riverpark. He mainly associates with Fingers, another old male (first seen in 1993) who has also shown similar ‘begging’ behaviour. This apparent change in their behaviour has two components:

1- The recent exhibition of ‘begging’ behaviour by both dolphins (neither was reported as a “beggar” dolphins during previous studies dating back to 1993); and

2- The recent expansion of their home range with observations of the two in the middle sections of the Swan Canning Riverpark.

 

Backpack begging

Summary of winter 2012 surveys

Product catching a fish

During our winter 2012 season, we encountered 31 groups of dolphins (compared to 24 during our previous winter season) in 5 cycles (a cycle is completed when the four areas – Cockburn Sound, Owen Anchorage, Gage Road, and the Swan Canning Riverpark – are surveyed). Group encountered doubled in winter 2012 (n = 6 in winter 2011 and n = 13 in winter 2012). However, we identified more individuals in winter 2011 (n = 182) than in winter 2012 (n= 127).

Tupac & her calf Gizmo

In addition, we surveyed the Swan Canning Riverpark 4 more times (i.e., not part of a cycle) and encountered 13 dolphin groups.

Among the dolphin we observed within the Swan Canning Riverpark were: Blackwall; Tworakes & her calf Zari; Print & Extreme (a suspected male alliance); Tupac & her calf Gizmo (who has recovered well from his entanglement); and Resource & her calf Product .

During our spring field season (Sept-Nov) in Bunbury, Western Australia, we were on the water for over 130 hours and encountered 64 groups of dolphins. Spring is an exciting time to conduct fieldwork because humpback whales pass on their southern migration. During this time, mother and calves pass closer to shore than on their northern migration. This spring we came across 12 humpback whale mum and calf pairs on our coastline transects. On two of these occasions the dolphins were associating with the whales. We also saw three mum and calf pairs of southern right whales, which is interesting, as we did not see any last year. Our whale images have been passed on to the SouWest whale research group for addition to their database.

Southern right whale along back beach, Bunbury.

Spring is also an exciting season because the flying fish come back into our study area. When driving along our transect lines searching for dolphins the boat scares the flying fish and they fly out of the water. We have also witnessed dolphins chasing after flying fish and last month we saw a dolphin leap out of the water and caught a flying fish in the air!

Flying fish, Bunbury, Western Australia.

As spring began, the cuttlefish spawning period was ending. The cuttlefish appear to aggregate around Bunbury during the winter and some dolphins take advantage of this. Since 2007, Dr Holly Raudino and myself have seen several dolphins feeding on cuttlefish after popping out the cuttle bone. This is a specialised feeding technique, which has only been reported previously in Adelaide, Australia.

“Comet” feeding on cuttlefish with her calf, “Milky way”, by her side.

Another, specialised feeding technique, which occurs in Bunbury, is octopus tossing. The dolphins repeatedly toss octopus several meters into the air making sure the octopus becomes limp. We have seen this event on multiple occasions even prior to 2007 from Dolphin Discovery Centre volunteers and SWMRP researchers. Our last occasion to witness this event was in October, where an adult male “Quicksilver” was tossing an octopus. Quicksilver did not appear to be concerned by the boat or the fact that he had a large shark bite on his side of his body.

“Quicksilver” an adult male dolphin tossing octopus.

In addition to “Quicksilver’s” shark bite, we have also recently seen “Gem” a juvenile female and “Harvey” an adult male with shark bites. We keep track of these dolphins and record the healing rate of their scars.

“Harvey” an adult male dolphin with a shark bite.

Apart from sharks, dolphins also have to watch out for other dolphins, especially male alliances. In October, we saw a male alliance approach another male alliance. These alliances greeted head on and began intensely interacting. The dolphins were chuffing (forced exhalations that created a loud sound), splashing and blowing bubble rings. “Razor” and “Star” reared up at “Hockey” and “Shaka” appearing to ram them out of the way.

“Star” and “Razor” rearing up out of the water pushing “Hockey” and “Shaka” out of the way.

 Summer has now begun and from January onwards, Krista Nicholson will be conducting my field data collection for my PhD. Over the spring quarter, I have been given the opportunity to attend classes on habitat modelling at Duke University. My co-supervisor, Dr David Johnston, is a lecturer at Duke University and my PhD thesis is based on habitat modelling so this is a special opportunity. However, I will miss being on the water each month with the dolphins, whales, hammerhead sharks, flying fish, fur seals, sea lions and little penguins.

I would like to thank my recent assistants for all their help; Kim from the Netherlands, Virginie from Switzerland, Thekla from France and a special thank you to Rene from Denmark who left his computer science job to help me out with my computer problems for a month! The research for the South West Marine Research Program is made possible through the funding partners, including, the Bunbury Dolphin Discovery Centre, Bemax Cable Sands, BHP Billiton Worsley Alumina, Bunbury Dolphin Discovery Centre, 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.

Earlier this year, MUCRU commenced research on the poorly understood Australian snubfin and Indo-Pacific humpback dolphins. This project aims to collect baseline information on their abundance, habitat use and genetic connectivity in the Kimberley region of northwest Australia.

Fieldwork began in April 2012 with a productive first trip to Cygnet Bay (Dampier Peninsula), followed by a successful but quieter month in Wyndham (Cambridge Gulf).

Here, MUCRU PhD candidate Alex Brown reports on a second trip to Cygnet Bay in September 2012…

If someone had said to me a month ago that I’d soon be staring at a photo catalogue of over 50 different snubfin dolphin individuals, and holding tissues samples for almost half of them, I’d have laughed it off as wildly optimistic. However, those numbers are now a reality, and illustrate the success of our recent trip to Cygnet Bay.

Departing Perth at the end of August, I was joined by team members Jenny Smith (USA), Dominic Clarke (UK) and Corinne ‘Coco’ Ackermann (Switzerland). We broke up the 2,500 km journey north with stops in Northampton, Shark Bay, Coral Bay, Cossack and Broome. A week later, we bounced our way up the Cape Leveque road to the pearl farm and research logistics base of Cygnet Bay.

A snubfin in smooth, clear waters – a rare and special sight. [Photo: Jenny Smith]

After just a few days on the water, it had become apparent that considerably more snubfin dolphin activity was being observed in the bay than on our previous visit. On first visit to this location, in April/May, snubfins were only encountered 14 times, were typically very shy of the boat, and not once observed engaging in obvious socialising behaviour. By the end of that trip, we had identified 16 different individuals (excluding calves) from marks on their dorsal fins.

A tightly packed group of snubfins curiously passes our boat. [Photo: Jenny Smith]

Snubfin OH023 being sampled, showing the moment the dart strikes.

Such was our success with biopsy sampling, that we collected tissue samples from 22 different adult individuals over the course of the month. We obtain these tissue samples using a well-established system of a modified rifle and floating plastic dart. The specially designed dart, which is tipped with a small metal coring device, bounces off the flank of the dolphin where the blubber is thickest and retains a few millimetres of skin and blubber**. From this we can analyse the DNA of the animals, revealing important information on the structure and connectivity of populations.

Humpback dolphin SC015, doing the “banana pose”

Humpback dolphins were also seen frequently, albeit in smaller numbers than the other species; we now have 22 different individuals photographed. Several socialising groups were encountered, with a few suspected males getting excited around females with leaps and stretches. Some interesting inter-species interactions were also observed, with what appeared to be an attempted mating event between a male humpback dolphin and a suspected female snubfin.

Humpback dolphin SC011 and her young calf

Many of the humpback dolphins we observed on a regular basis were females with calves, including “SC011” who has given birth since our last visit. With the pearl farm crew photographing this animal alone in July, we know the calf to be less than two months old.

Bottlenose dolphin TA042 sizes us up through calm waters.

We also collect information on any bottlenose dolphins (Tursiops aduncus) that we encounter. On our last visit to Cygnet Bay, bottlenose dolphins were by far the most commonly encountered species, and appeared to be present in the greatest numbers. This time, however, the encounter rate was roughly the same for each of the three species. We observed many of the same individuals as last season, but also some new animals, taking the catalogue to 53 identifiable bottlenose dolphins in total. A further nine tissues samples were obtained for this species.

The team at work – biopsy sampling [Photo: Simon Allen]

Despite the latter mechanical gremlins, it was a remarkable and very successful month. Was the striking difference in snubfin activity between Apr/May and Sep/Oct a genuine seasonal change, or are there other factors at play? With just two months for comparison, we don’t have enough information to answer such questions at this stage. It will be very interesting to see if a similar difference in activity is observed next year…

My thanks goes out to the team, who pushed through the heat, ailments, and a distinct lack of time off, to gather and process a mountain of valuable data. Once again, the Kimberley Marine Research Station at Cygnet Bay were fantastic hosts – their logistical support and subsidised accommodation continue to provide a valuable contribution to this research.

Here is a selection of images from various encounters over the month.

**Note: the aforementioned activities were conducted under the following permissions/licences: Department of Agriculture and Food U6/2012-2014; Department of Environment and Conservation, WA, SF008480; WA Police 9990071; Murdoch University Animal Ethics Committee W2342/10.

We were back in Shark Bay, WA, in August/September to conduct the ultimate trial of the UAV, and it was a showdown between two teams: the UAV team – six staff from Insitu Pacific, and the Human team – five aerial survey observers and a pilot flying in the Partenavia. Both teams flew the same survey lines (transects) at the same time, so we can finally test whether the UAV images can detect the same number of dugongs that human observers can.

Rest assured both teams took this challenge very seriously. The very experienced team of observers and the pilot love their job, particularly when you get to see places as beautiful and fauna rich as Shark Bay, from the air. But the UAV team were very determined to show the capabilities of their drone and were quick to point out all of its advantages.

The UAV and Partenavia (with the human observer team on board) in flight

My grand plan was to survey all of Shark Bay, using the same survey plan that has been flown during the 5 previous surveys conducted in the Bay since the 1980s (see map below). We had 8 days of flying to achieve this mission, and needed good weather (low winds). To our enormous relief, the weather was kind most of the time.

The most challenging task was for the pilot and the UAV operators to actually start each survey line at the same time. The two were flying at different altitudes and at different speeds (the UAV is a bit slower). The pilot of the Partenavia did an amazing job of accounting for that in timing his holding patterns at the end of each transect. Hats off to both teams – I honestly wasn’t convinced it could be done but through excellent radio communication and planning, they nailed it.

Ultimately I wanted to survey areas where there were a lot of dugongs, because I needed a large sample size in order to compare the sightings of the two teams. The human observers spotted a lot of dugongs in blocks 3, 4 and 5 (see map below), so I although we could have surveyed the remainder of Bay, I decided to survey some of these blocks twice. This means I can investigate the effects of different survey conditions (cloud, wind, glare) on detection rates of dugongs in images versus by humans.

Another member of our field team was Gwénaël, who is developing computer software that will detect the dugongs in the images automatically. This is a vital part of the project – during this field trial we collected 73,000 images, and that is large number of images to manually review! His work is continuing, but he was able to test his algorithms on these new images and advise me on matters such as camera settings and image resolution, so that the images we were collecting would work well with his software.

So who won the showdown? To answer that question I now need to use a combination of manual review and the detection software to find all the dugongs in the thousands of images. This will take quite some time, and I will need to enlist the help of some willing helpers…

Shark Bay survey plane flown by both the UAV and unmanned plane

For my PhD, I am carrying out year-round surveys of Indo-Pacific bottlenose dolphins in Bunbury, Western Australia. Last year we expanded our study area by adding on two offshore transects that extend 10km from shore to the 20m depth contour (view transect lines here).

We hypothesised that in winter adult males would move offshore, helping to explain their larger home ranges. As winter approached we were looking forward to what we would find.

June was the first month of our winter season and right there and then we came across the first adult male group, which just happened to be a male alliance. “Rocky” and “Triton” were in 15.3m depth of water at 18°C and they were travelling further offshore. The Leeuwin current is a warm water current which flows southwards along the coast and is strongest in the winter time. The current flows offshore from Bunbury and this warm water and the associated prey species could be reasons to why dolphins venture into the deeper waters. Whilst offshore, we documented several feeding events, including dolphins tossing octopus and snacking on bait fish (see picture above).

The clear waters on our offshore transects (extending up to 9.26km offshore)

In total for the winter season, we completed nine offshore transects where we encountered dolphins on four occasions. We followed dolphins 10km offshore in >23m depth of water. Group sizes ranged from three to thirty and amazingly in each sighting there was at least one male alliance. This is interesting, as it is helping to explain the ranging patterns of adult males. Overall, nine male alliances were sighted, including a re-sighting of Rocky and Triton three times.

A male alliance synchronising thier movements

Rocky and Triton have been in an alliance since at least 2007 and during the winter they were found escorting an adult female dolphin named “Cracker”. Cracker was first sighted in the middle of three male alliances in July and then again two weeks later in the middle of the same three alliances. Perhaps these males had formed a ‘super alliance’ like they do in Shark Bay. Cracker is the mother of “Gouda” and unfortunately the calf was not seen during this time. We have been suspecting that Gouda could be the dolphin that was found floating dead in Koombana Bay. Volunteers from the Bunbury Dolphin Discovery Centre helped to retrieve the carcass and a necropsy by MUCRU vets was performed. However, the cause of death is not confirmed due to the high level of decomposition.

Another necropsy that MUCRU vets carried out was on an adult male dolphin named “Fold”. Fold was in a male alliance with “Fuji” and “Star”. By the state of the body it had not been dead for long, so we drove it straight to Murdoch University for a necropsy. It was determined that Fold (2.52m long) died due to severe blunt force trauma; perhaps from being rammed by another dolphin or a vessel. Now that Fold has passed and Fuji has also disappeared, the last alliance member, Star, may find new alliance partners. We will be keeping a close eye on any new associations with Star.

Although we have witnessed two deaths we have also recorded several winter births! Births in winter are unusual as the water temperature is lower than the peak birthing seasons (Summer-Autumn), reducing the calf’s chance of survival. We will be keeping an eye on these calves, including “Lumpy’s” baby “Limpet” and “Iona’s” baby “Tiree”.

“Lumpy and her winter neonate “Limpet”

During the winter we were on the water for over 130 hours (with 64 dolphin group sightings). I would like to thank my assistants who braved the cold, wet winter days. A special thank you to my current interns Hannah from Germany and Charlotte from France, who are here for three months and have helped out substantially; especially with going through the thousands of photographs we have of dolphins dorsal fins.

A Bunbury winter sunrise

The research for the South West Marine Research Program is made possible through the funding partners, including, the Bunbury Dolphin Discovery Centre, Bemax Cable Sands, BHP Billiton Worsley Alumina, Bunbury Dolphin Discovery Centre, 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.

In the middle of May, MUCRU’s Kimberley inshore dolphin team left the blue waters of the Dampier Peninsula to travel deep into the eastern Kimberley.

With sealed road access to the coast entirely absent for over 900 km east of Derby, our options for launching a vessel in this area were somewhat limited. So we chose Wyndham as our base for the month, giving us access to the Cambridge Gulf – where we had heard reports of humpback, snubfin and bottlenose dolphins occurring.

The Kimberley, courtesy of Google Maps. Wyndham is marked ‘A’.

After departing Broome, we passed through Derby, Fitzroy Crossing then Halls Creek, before the scenery changed dramatically. Wild grassy plains dotted with thick old boab trees and ancient lumps of red rock, numerous tree-lined creek beds, and a backdrop of hills capped by ochre sandstone cliffs.

The grassy plains of Parry Lagoons in the dry season.

Unlike our previous more coastal study site, Wyndham sits some 100 km inland of the open coastline. Its adjacent waters are therefore more estuarine in nature, with lower salinity and much reduced water clarity. The Pentecost, Durack, King, Ord, Forrest and several other rivers converge into this estuary system to form a vast swirling mass of crocodile-infested muddy water – collectively referred to as the Cambridge Gulf.

Passing beneath the cliffs of “The Gorge”

Much of the gulf and its rivers are bordered by expansive mangrove-fringed mudflats – bleached and cracked by the sun in the dry season, and flooded in the wet. In many places, however, the underlying geology juts spectacularly into the air, leaving sheer red cliffs and rocky hills towering out of the water to several hundred metres high. Below the surface, the seabed plummets to depths of up to 60 m between narrow gorges, where any uneven bathymetry sends the strong tidal currents into a maelstrom of boiling eddies and whirlpools.

Unfortunately, our arrived coincided with a prolonged period of windy weather. For two weeks, the entire north-west cost was buffeted by strong easterlies. Such conditions made the chance of spotting dolphins extremely low, and we were unfortunately fruitless in our searches over this period. We did, however, observe a few other interesting creatures through our endeavours.

Saltwater croc up the King River

Black flying foxes, roosting among the mangroves

We tried to utilise local knowledge of these waters as much as possible, speaking to those who spent much time on the water. Most were in agreement that they do occasionally see dolphins, but only in small numbers and they generally keep their distance from boats. The locations of where they had seen dolphins were widespread, ranging from offshore sandbanks in the outer gulf to 35 km up the King River. Unexpectedly, reports suggested that most frequently encountered dolphins in the deeper, narrow sections of the inlet where the currents were at their strongest.

And, when the winds finally eased, small numbers of very shy dolphins was exactly what we observed. Over the latter 2.5 weeks at the site, better conditions enabled us to complete our 5 pre-determined transects, and explore a little further north of our core study area towards the more open coastline. Over this period we sighted snubfin dolphins on 10 occasions, and humpback dolphins on 7. We did not observe any bottlenose dolphins.

Can you see the snubfin?

While the number of encounters was low, it was interesting to observe them in such different habitats to our previous study site on the Dampier Peninsula. The majority of our sightings here occurred in the deeper, narrow sections where the currents were at their strongest. With such fleeting glimpses of snubfins in these areas, it is not possible to say much on their behaviour in these areas – were they foraging, or just passing through?

Snubfin mother and calf

Our last two days on the water were more productive, in terms of animals sighted, than the previous 4 weeks. When further north into the wider body of the Cambridge Gulf, where the Lynne and Helby Rivers feed in from the west, we observed several groups of snubfins, including a group of 3-4 foraging over shallower flats and our first confirmed mother-calf pair in this area.

With a low number of unapproachable animals encountered, our objectives of photo-ID-derived abundance estimates and biopsy sampling seem unlikely to be achieved in the waters around Wyndham. Despite this, our efforts represent the first structured investigations of dolphins in this area, and provide valuable information on the relative encounter rates of animals and the habitats in which they occur. We’ll now consider alternative sites for next season which may yield sufficient numbers of animals to suit our techniques and objectives.

Thanks goes to my two assistants Jo and Kelsey, who were brilliant throughout and kept up the enthusiasm even on consecutive 10 hour days without dolphins. We are grateful to all the people of Wyndham who welcomed us and took the time to share their dolphin encounters with us, including all the managers and friendly inhabitants of the caravan park. Particular thanks goes to Alan of the East Kimberley Sea Rescue for his radio coverage over this large and remote area, not to mention all the edible pickings from his garden. Thanks also to Cat and David of Save the Gouldian Fund for taking us birding, and the guys from Stop the Toad for the reptile encounters at El Questro.

More photos from the trip can be viewed here.

Sunset over El Questro wilderness park

Over the past 1.5 years, I have been carrying out dolphin surveys for my PhD in Bunbury, Western Australia, as part of the South West Marine Research Program. During this time my assistants and I have been boating for over 550 hours. Spending this much time on the water allows us to experience some amazing dolphin behaviour, such as feeding (see video below courtesy of Seadog Films)!

Over the summer season we commonly encountered large groups of dolphins (>20 individuals) herding schools of fish, such as whiting. Seagulls, terns and cormorants would also join in the excitement (see pictures below and click to enlarge).

Other feeding events have occurred by chance, for example, we recorded the dolphins “Darwin” and “Rio”, who are suspected males, feeding in clear shallow waters last Autumn. Darwin came right up to the boat teasing a small Western Butterfish, whilst Rio chased an Australian Herring.

In the winter time many of the adult female dolphins and their calves congregate in the inlet where the salt water mixes with the fresh water from the river. The dolphins are commonly foraging in this area and we recently found an adult female dolphin “Tipex”, repeatedly whacking a cobbler fish on the water’s surface.

We have also witnessed several dolphins feeding on cuttlefish and tossing octopus into the air. The giant cuttlefish have occurred in Bunbury during the winter season, whilst the octopus can be found year round. To date, we have recorded the dolphins Dane, Lunchbox, Boomer and Trio tossing octopus several times in a row high into the air making sure the octopus is dead.

I would like to thank my volunteer assistants and the sponsors for the  South West Marine Research Program who make our research possible; the Bunbury Dolphin Discovery Centre, Bemax Cable Sands, BHP Billiton Worsley Alumina, Bunbury Dolphin Discovery Centre, 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.

Megafauna-galore in Hawai’i !!

This month (June 2012) concluded the 21^st month of photographic identification effort of Hawaiian spinner dolphins along the Kona coast of Hawai’i Island.The SAPPHIRE dolphin catalogue now includes 620 distinctive individuals.   Over the past three months (April-June), we have been on the water for 42 days (365 hours). Of these, 36 days were spent photo-identifying spinner dolphins. In this time period, we took more than 25,000 images of spinner dolphins. We spent six days retrieving and deploying our acoustic loggers.  Since we commenced the SAPPHIRE project in September of 2010, we have spent a total of 252 days on the water carrying out photographic identification, amounting to 182,000 images. Furthermore, we have in excess of 6,000 hours of acoustics recordings from four resting bays along the Kona coast.

Click here to listen to spinner dolphin vocalisations

Spinner dolphin (Stenella longirostris) mother, calf and remora

False killer whales (Pseudorca crassidens)

Makako Bay (our northern most study site) has been featuring large spinner dolphin groups on a regular basis since January 2012. Here, dolphin group sizes typically range in the hundreds, and this month was no exception.  Each encounter is unique with group sizes fluctuating from month to month, day to day, and even hour to hour. During a survey in Makako Bay on the 18th of March we were conducting an approach towards a group of spinner dolphins for photo-identification.Suddenly, the group of dolphins changed direction and we observed an increase in surface and aerial behaviours. To our surprise we then noticed several false killer whales where the group of spinners had been only moments earlier.

False killer whale (Pseudorca crassidens) in Makako Bay

Rough-toothed dolphins (Steno bredanensis) and hammerhead sharks

Furthermore, since March 2012, we have sighted several other marine species during our spinner dolphin research, including hammerhead sharks ,  bottlenose dolphins, spotted dolphins, and most recently, a sighting of two oceanic white tip sharks following a group of rough-toothed dolphins.

Rough toothed dolphins (Steno bredanensis) along the Kona coast, Hawai’i

Focal follow, from left to right Laura Ceyrac, Miriam Battye and Tasha Boerst

In June, we have undertaken two focal follows; during focal follows we run transect either north or south out of Keauhou Bay (our primary boat launch point) and look for spinner dolphin groups.

When a dolphin group is encountered, we collect photographic identification data before conducting behavioural surveys. Behavioural surveys record the general group behavioral state, position, potential sources of anthropogenic influence (including our own boat), and the continuous recording of 13 conspicuous behaviour events for the duration of time with the focal dolphin group.

The SAPPHIRE project would like to say a big thank you to John Symons, who has been helping out on the project since April 2011. Since the end of January 2012, John has been running the field season for Julian until he returns to Kona in July for another six months.  It is with great pleasure that we can inform you that John has been accepted into a postgraduate Masters program at University of Aberdeen, Scotland, and we wish him the very best of luck in his endeavours.