May 2016 – New publication in Molecular Ecology

Hot on the heels of our recent publication in Frontiers (see: Rankin R, Nicholson K, Allen S, Krützen M, Bejder L, Pollock K (2016). A full-capture Hierarchical Bayesian model of Pollock’s closed robust design and application to dolphins. Frontiers in Marine Science 3: 25. DOI: 10.3389/fmars.2016.00025), we are very pleased to announce the publication (online early view) of our most recent paper in Molecular Ecology:

Title: Genetic isolation between coastal and fishery-impacted, offshore bottlenose dolphin (Tursiops spp.) populations.

Authors: Simon Allen, Kate Bryant, Robert Kraus, Neil Loneragan, Anna Kopps, Alex Brown, Livia Gerber and Michael Krützen.

Abstract: The identification of species and population boundaries is important in both evolutionary and conservation biology. In recent years, new population genetic and computational methods for estimating population parameters and testing hypotheses in a quantitative manner have emerged. Using a Bayesian framework and a quantitative model-testing approach, we evaluated the species status and genetic connectedness of bottlenose dolphin (Tursiops spp.) populations off remote northwestern Australia, with a focus on pelagic ‘offshore’ dolphins subject to incidental capture in a trawl fishery. We analysed 71 dolphin samples from three sites beyond the 50 m depth contour (the inshore boundary of the fishery) and up to 170 km offshore, including incidentally caught and free-ranging individuals associating with trawl vessels, and 273 dolphins sampled at 12 coastal sites inshore of the 50 m depth contour and within 10 km of the coast. Results from 19 nuclear microsatellite markers showed significant population structure between dolphins from within the fishery and coastal sites, but also among dolphins from coastal sites, identifying three coastal populations. Moreover, we found no current or historic gene flow into the offshore population in the region of the fishery, indicating a complete lack of recruitment from coastal sites. Mitochondrial DNA corroborated our findings of genetic isolation between dolphins from the offshore population and coastal sites. Most offshore individuals formed a monophyletic clade with common bottlenose dolphins (T. truncatus), while all 273 individuals sampled coastally formed a well-supported clade of Indo-Pacific bottlenose dolphins (T. aduncus). By including a quantitative modelling approach, our study explicitly took evolutionary processes into account for informing the conservation and management of protected species. As such, it may serve as a template for other, similarly inaccessible study populations.

The full citation is Allen SJ, Bryant K, Kraus R, Loneragan N, Kopps A, Brown A, Gerber L, Krützen M (2016). Genetic isolation between coastal and fishery-impacted, offshore bottlenose dolphin (Tursiops spp.) populations. Molecular Ecology doi: 10.1111/mec.13622

You can find the paper at URL: http://onlinelibrary.wiley.com/doi/10.1111/mec.13622/full

 

 

May 2016 – And so it begins in the West… with wind, William, and a weather balloon (sort of)!

 

The western gulf field season has kicked off with a ba… aad stretch of windy weather. Low-pressure system after low-pressure system in the aptly named roaring 40s to the south of the Land of Oz have meant the infamous ‘sausage highs’ over Shark Bay and the associated howling sou-easters. So much for the magnificent ‘May in the Bay’!

On the positive side though, the team was well and truly ready to roll when the first lull appeared. We scored four days, or part there-of, in a row, and made data collection happen while the sun shone.

We ventured into the Denham Channel just southwest of the ship loader on the first afternoon out. What started as an encounter with a single adult male dolphin soon turned into 26 animals, including members of four different male alliances and a few females. Cameras snapping, hydrophones in, dolphins a-socialisin’!

1 Social dolphins

1. A socialising sub-group of Shark Bay dolphins.

 

Conditions seemed to favour a look in Useless Inlet the following day… we were duly rewarded after a few surveys, finding the famous William the Concherer (yes, yes, we now know they’re not conches, but it sounds a whole lot better than William the Shellerer!). As the Inlet went to a glass out, the first focal follow of the season saw constant foraging, and several shelling events. Some hours later, we returned to the boat ramp at Cosy Corner, the evening sun casting glorious light. There is nothing Useless about this Inlet (unless, of-course, you’re a colonial white fella in desperate need of fresh water).

2 William the trumpeter 3 Inlet magic

2. William forages in Useless Inlet; 3. Bellefin and Heirisson Prongs float atop a horizonless bay.

 

The next day saw some surveys of the usual suspects in the shallows north of Heirisson Prong, before we again found ourselves in the Inlet. Plenty of action followed, including foraging dolphins (and cormorants), a male alliance moving in on some females and calves, and the satisfaction of lengthy focal follows with cameras, hydrophone array and the helikite deployed.

4 Dolphin breakfast5 Corm breakfast

4. Not cat and mouse, but dolphin and fish; 5. A cormorant tastes success too.

 

8 Five for fighting

6. Five for fighting

 

6 Team in action7 Phileas Fog

7. The team at work (Helen Hiley, Sonja Wild and Dr. Stephanie King), not fishing but ballooning; 8. Our trusty helikite/balloon (“Phileas Fogg”) with GoPro attached.

 

The last of our four data days involved more Shark Bay magic: dolphins, turtles, dugongs, cormorants, pelicans, a couple of hammerhead sharks… having now been off the water due to another five days of wind though… well, tomorrow is a new day.

9 When allies approach10 Floppy and Hartog

9. The stuff that prompts action stations when we’re on a follow – the approach of potential allies; 10. Said allies travel south with Dirk Hartog Island as the backdrop.

 

Stay tuned for more updates!

Feb 2016 – Natural born killers!? …or just another big, smart, social mammal?

Happy 2016!
The BBC website recently published an article that discusses some of our research. It’s quite a nice article, even if the title is a little over the top (the author did a great job, but did not select the title!). It should not surprise us that an animal that is so intelligent engages in some violent behaviour – something Shark Bay’s dolphins do in incredibly complex alliances; we only have to look in the mirror for that.

See also Richard’s post on the Dolphin Alliance’s Facebook page: https://www.facebook.com/dolphinallianceproject/?fref=ts

Dec 2015 – The Shark Bay Dolphin Research Alliance at the 21st Biennial Conference on the Biology of Marine Mammals in San Francisco

The Dolphin Innovation Project and Dolphin Alliance Project were well represented at the recent biennial conference of the Society for Marine Mammalogy held in beautiful San Francisco, California. Richard gave a presentation on yet another fascinating finding from the long-running research into male alliances, and special congrats go to PhD students Whitney and Sonja, who gave their first international conference presentations. Stephanie’s earlier research on signature whistles in dolphins also got covered in Professor Peter Tyack’s plenary talk.

Following are the presentation titles and authors (Shark Bay Dolphin Research Alliance members in bold and those who presented underlined). As well as these four(*) presentations specifically by members of the SBDRA, we contributed to numerous other posters, speed talks and full presentations by our friends, colleagues and associates at other labs/research groups:

 

*1. “Consortship rate and alliance structure vary with habitat in a large bottlenose dolphin (Tursiops cf. aduncus) social network.” Talk by Richard Connor, William Cioffi, Srdan Randic, Jana Watson-Capps, Simon Allen, William Sherwin and Michael Krützen

*2. “Social complexity among bottlenose dolphins (Tursiops aduncus): Dynamic third-order relationships and processes of mediation.” Talk by Whitney Friedman, Richard Connor, Michael Krützen and Edwin Hutchins

*3. “Female dolphins who are heterozygous for MHC do not produce more offspring, but their offspring are more viable.” Talk by Oliver Manlik, Janet Mann, Michael Krützen, Anna M Kopps, Holly C Smith, Kate R Sprogis, Lars Bejder; Simon Allen, Richard C Connor, William B Sherwin.

*4. “Shelling out for dinner: Evidence for horizontal social transmission of a remarkable foraging strategy in a wild dolphin population.” Poster by Sonja Wild, William JE Hoppitt, Simon J Allen and Michael Krützen

 

5. “Estimating the proportion of unmarked individuals in delphinid populations”. Poster by Krista Nicholson, Michael Krützen, Simon J Allen and Kenneth H Pollock

6. “Sexual dimorphism and geographic variation in dorsal fin features of Australian humpback dolphins.” Poster by Alexander M Brown, Lars Bejder, Guido J Parra, Daniele Cagnazzi, Tim Hunt, Jennifer L Smith and Simon J Allen

7. “Bite me: Inferring predation risk from the prevalence of shark bites among three tropical inshore dolphin species in north-western Australia.” Poster by Felix Smith, Simon J Allen, Lars Bejder and Alexander M Brown

8. “Australian humpback dolphins (Sousa sahulensis) of the North West Cape, Western Australia: An important habitat toward the south western limit of their range” Speed talk by Tim Hunt, Lars Bejder, Simon J Allen and Guido J Parra

9. “Introducing the Australian humpback dolphin (Sousa sahulensis): Biology and status of the World’s ‘newest’ dolphin species.” Poster by Thomas A Jefferson, Guido J Parra, Simon J Allen, Isabel Beasley, Alex Brown, Daniele Cagnazzi, Tim Hunt and Carol Palmer

We look forward to presenting more of our research and catching up with friends and colleagues in Halifax for the 2017 conference.

 

Oct 2015 – Epic endings and new beginnings: Summary of the Dolphin Alliance Project’s (Monkey Mia) field season

The 2015 field season was incredibly successful thanks largely to our amazing crew (Teresa Borcuch and Giulia Donati), without whom this success would not have been possible. In four months, we conducted hundreds of behavioural surveys across our entire study area and collected more than one hundred tissue samples.

We are sad to report that several dolphins, whom we have known for decades, have no longer been sighted in recent times. The most prominent among those missing is Real Notch, an old Red Cliff Bay male who had an impressive record spanning three decades – both when it comes to consortships and also paternities. He will be sorely missed, but will live on in our memories, in scientific papers and in legend!

Another loss this year was Nicky, one of the regular visitors to Monkey Mia beach. She was probably one of the most well-known and most frequently photographed wild dolphins in the world. Her disappearance in June, just short of 40 years of age, has made international headlines and thousands of people have expressed their condolences over social media. She left behind her two and a half year old calf, Missel. While we were hopeful at first, she was last sighted a couple weeks after Nicky’s disappearance and has, unfortunately, not been sighted again since.

The dolphin society is changing! Many of the male alliances who have dominated the eastern gulf in recent years are slowly disappearing, existing alliances are changing, and we have identified several potential new alliances, with young male dolphins who might take the old alliances’ place in the years to come. Only time and continued survey effort will tell if they succeed. The 2016 season is just around the corner and we aim to make it as successful as 2015 has been.

Sam and Team East

 

DAP season 3 DAP season 4 DAP season 2

 

 

Oct 2015 – Done, but not forgotten… summary of the Dolphin Innovation Project’s (Useless Loop) field season

The four-month field season out of Useless Loop in 2015 is (relatively speaking) ancient history… but it won’t be forgotten: hundreds of surveys were completed, thousands of photos and videos collected, association data on shellers and spongers collected, and lots of new samples obtained. It’s all in the (data)bank!

Now in the midst of data analysis, we happily remember our days in the field… the group of more than 30 males (several 2nd-order / nested alliances) competing for a female, LEI the dolphin carrying a huge sponge that nearly covered her eyes, the shovelnose ray nearly as large as our beloved little boat, seeing Oakley the female dolphin getting larger and larger and then, finally (!), with her 3-day old calf, and, of-course, living and working in one of the world’s most remote and fascinating places.

We are excited to gain further insights into the complex cooperative and foraging behaviours of Shark Bay’s bottlenose dolphins from the data collected during this and previous seasons… but, at the same time, we can’t wait to go back to the Bay in 2016!

Team West (Livia Gerber, Sonja Wild, Manuela Bizzozzero and Felix Smith)

 

1 copy

Aug 2015 – Some Mothers Do ‘Ave ‘Em

3e Nicky 2005

One of the most famous of the Monkey Mia beach dolphins, Nicky (pictured above in 2005) died last month. She was just shy of her 40th birthday. Only a small percentage of dolphins in Shark Bay are lucky enough to live past 40 years of age. Nicky’s mother, Holey-fin, died this same month 20 years ago.

This video clip shows Nicky interacting with her first infant, Nipper, in 1988, when Nipper was just one year old. The interactions were filmed by Scott Crane, who was helping us out that year. Although the interaction appears very “cute”, with Nipper in “baby position” and nuzzling and rubbing against her mother, it reflects an infant trying to get attention from a mother who was more focused on the free fish available at Monkey Mia.

Nicky certainly wasn’t the best mother in the bay, and her only surviving offspring (pictured with her below as a youngster in 2012), now a juvenile, remains her only opportunity to leave a lasting legacy. 

4e Nicky and calf 2012

Her poor performance stands in stark contrast to other Monkey Mia females, like Puck and Surprise, who have been very successful and are now grandmothers. Nicky and Puck were born a year apart. Nicky was originally thought to be a male and was named Nick based on the large nick in her dorsal fin. Following the naming of Nick, A Midsummer Night’s Dream was the inspiration for Puck. The dolphin versions of Nick and Puck could not have had more different personalities, but in ways different from the play! Nicky was quite aggressive, while Puck (whose daughter and granddolphin are pictured below in 2012) has always had a sweet, gentle disposition.

Puck's daughter and grandaughter

See also Richard’s posting at https://www.facebook.com/dolphinallianceproject?fref=ts

17 Jun 2015 – The 2015 field season kicks off in Shark Bay!

sponge

The 2015 field season, with researchers Sam Wittwer and Teresa Borcuch on the Monkey Mia side (Dolphin Alliance Project) and Livia Gerber and Sonja Wild on the Useless Loop side (Dolphin Innovation Project), has been successfully kicked off.

Both teams (including PhD students, Masters students and volunteers from four different countries) will stay in the field until mid-October, collecting photo-identification, behavioural and genetic data. They’ll see oh-so-many dolphins, fascinating foraging and complex cooperation and competition… not to mention flying fish, sharks, rays, dugongs, turtles, birds, sea snakes, sun rises, sunsets and so on.

Interested in joining as a volunteer in future years? If so, please contact Michael, Richard or Simon.

May 2015 – New Publication in Animal Behaviour

ESBDolphin BB flank female

We are pleased to announce the publication of “Male dolphin alliances in Shark Bay: changing perspectives in a 30-year study” in Animal Behaviour

Authors: Richard Connor and Michael Krützen

Abstract: Bottlenose dolphins, Tursiops cf. aduncus, in Shark Bay, Western Australia exhibit the most complex alliances known outside of humans. Advances in our understanding of these alliances have occurred with expansions of our study area each decade. In the 1980s, we discovered that males cooperated in stable trios and pairs (first-order alliances) to herd individual oestrous females, and that two such alliances of four to six, sometimes related, individuals (second-order alliances) cooperated against other males in contests over females. The 1990s saw the discovery of a large 14-member second-order alliance whose members exhibited labile first-order alliance formation among nonrelatives. Partner preferences as well as a relationship between first-order alliance stability and consortship rate in this ‘super-alliance’ indicated differentiated relationships. The contrast between the super-alliance and the 1980s alliances suggested two alliance tactics. An expansion of the study area in the 2000s revealed a continuum of second-order alliance sizes in an open social network and no simple relationship between second-order alliance size and alliance stability, but generalized the relationship between first-order alliance stability and consortship rate within second-order alliances. Association preferences and contests involving three second-order alliances indicated the presence of third-order alliances. Second-order alliances may persist for 20 years with stability thwarted by gradual attrition, but underlying flexibility is indicated by observations of individuals joining other alliances, including old males joining young or old second-order alliances. The dolphin research has informed us on the evolution of complex social relationships and large brain evolution in mammals and the ecology of alliance formation. Variation in odontocete brain size and the large radiation of delphinids into a range of habitats holds great promise that further effort to describe their societies will be rewarded with similar advances in our understanding of these important issues.

You can access the article at: http://www.sciencedirect.com/science/article/pii/S0003347215000810