Notes from the field: guest post from Laura Bogaard

by oceansadminAcoustics, Dolphins, Women in SciencePosted on No Comments
Humpback whale flukes with killer whale rake marks (PC: Laura Bogaard, for Oceans Initiative)
Humpback whale flukes with killer whale rake marks (PC: Laura Bogaard, for Oceans Initiative)

It was another beautiful day in the North Island neighborhood and Team Dolphin was all aboard our trusty research vessel, Wishart. We were cruising up Tribune Channel in search of our study animal, the Pacific white-sided dolphin (Lagenorhynchus obliquidens). The water was a magnificent pale blue—a reflection of the late-summer sky, and an indicator that this channel was once the path of an enormous glacier, which carved out the intricate valleys that make up the channels and inlets of the Broughton Archipelago.

All eyes were squinted against the glare as we scanned the waves for fins or splashes—any indication that there were dolphins in our midst. Off in the distance, three tall columnar blows gave away the position of a group of three humpback whales (Megaptera novaeangliae) making their way down the channel in our direction. We decided to slow our course in order to snap a few ID shots. We waited a few minutes for another surfacing and then, as if on cue, three more blows erupted through the surface almost in unison. One right after the other, each whale turned and dove deep into the blue water, flipping their tails and exposing their flukes as they descended. Armed with rapid reflexes and two spectacular cameras, Rob and I were able to grab ID shots for each whale in the short window of time that their flukes were vertical and above the water.

This is a photo I took from that encounter. The dark parallel lines you see are killer whale (Orcinus orca) rake marks that this whale probably sustained during a run-in with a transient orca. The scars left behind will help lead to an individual identification of this particular whale. Even after seeing them almost everyday this month, the size and agility of these creatures still astounds me.

The humpback’s smaller and speedier cetacean cousins, the Pacific white-sided dolphins, had the spotlight this season for Erin and Rob’s research project. They were quite a bit trickier to photograph than the humpback whales because of their speed and unpredictable behavior. After a month of working with them almost every day and shooting thousands of photos, I feel like I am finally getting the hang of it. Photographing wildlife can be a challenging experience, but with the right amount of patience, persistence, and positivity, the results are incredibly rewarding.

My favorite job on the boat was operating the hydrophone. Like photography, there was a bit of a learning curve. It took quite a few tries to get the hang of wrangling the long wire and recording in time to catch some vocalizations. Sometimes the dolphins would suddenly change their behavior and squall away at high speeds out of the detection range. Sometimes they were just silent. However sometimes, once the engine was off, the hydrophone was in the water, and the recorder and amplifier were switched on (given the batteries were charged and the SD card was in its slot), the voices that came through my headphones were simply breathtaking. This piece of equipment allowed me to access an underwater world that few people are lucky enough to experience. Listening to their whistles and calls as they communicated with each other and to their buzzes and clicks as they echolocated in search of food, added a whole new dimension to observing their behavior at the surface. It gave me a new appreciation for their complex sociality as well as the impact that ocean noise must have on their daily lives.

This is just a taste of a few of the wonderful experiences I have had this month during my Experiential Learning internship working with Oceans Initiative. I’m sad to leave the dolphins behind as this season comes to a close, but I am looking forward to working with Rob and Erin more this winter to help analyze the acoustic data we have been collecting over the last month for my Keystone thesis project at Quest University.

I have learned so much about the many different aspects that are involved in researching cetaceans. I can’t thank Erin, Rob, and Doug enough for being patient mentors and for making my dream come true by bringing me along to Malcolm Island for their field season. Thank you to Clara for the giggles, the sing-along-life-lessons, and for being such a trooper. Thank you MaryAnn for your generosity, warmth, and fabulous suppers. And finally, thank you to the unsinkable Molly Brown Dog for the slobbery kisses, being the best team mascot, and for always being there to keep my hands warm on the boat.

 

Laura Bogaard

September 24, 2016

 

 

Laura deploying a CPOD -- a high-frequency recorder that detects the echolocation clicks of killer whales, dolphins and porpoise.
Laura deploying a CPOD — a high-frequency recorder that detects the echolocation clicks of killer whales, dolphins and porpoise.
Molly Brown
Molly Brown Dog being helpful
Doug searching for dolphins
Doug searching for dolphins

The dolphin days of summer

by oceansadminConservation, Dolphins, Human Impacts, Populations, Wildlife Health, Women in SciencePosted on 2 Comments

Our team has arrived in the Broughton Archipelago and we are poised to carry out our dolphin photo-ID, health assessment, and disturbance studies. This year, we are thrilled to have an amazing team Laura Bogaard and Doug Sandilands. Laura, a student from Quest University, is our newest research assistant. Doug Sandilands has been working with the incredible team at The Center for Coastal Studies in Cape Cod as part of their large whale disentanglement program. As you all know, Doug is one of a kind and we are so happy to have his help.

Our dolphin health and conservation status project monitors health of individual Pacific white-sided dolphins and their population(s) in the Pacific Northwest. Thanks to Alexandra Morton’s pioneering work on this species, we now have a combined >25 years of data. This project is yielding new insights into the biology of the dolphins themselves, and ultimately about the health of the Salish and Great Bear Seas. In 2015, we launched a health study in partnership with Dr. Stephen Raverty to collect dolphin breath samples on petri dishes to screen for pathogens. This year, we plan to look for drug-resistant bacteria (e.g., linked to agricultural and sewage runoff) and how pathogen exposure changes in urban versus wild marine environments.

A second aim of our work this year is to assess the impact of human disturbance on dolphin behavio(u)r and populations. This non-invasive study will merge our past work on the impacts of vessels, noise, and other sources of disturbance (e.g., on resident killer whales) and the long-term demographic study to understand the population consequences of disturbance. We are not playing noise to the dolphins, but we will use their responses to our own boat and to large ships to explore how much harder dolphins may have to work to find food in a quiet versus noisy habitat.

Our first day on the water was a huge success. We encountered a few hundred Pacific white-sided dolphins foraging in a beautifully coordinated group. Many of the dolphins were well-marked, about 10% of the group were moms with babies, and the dolphins were vocalizing to one another in addition to echolocating. Please check out our Instagram account for more photos.

We look forward to sharing our notes and observations. Thank you to everyone for your support with launching these projects! Please sign up for our newsletter (see sidebar) if you’d like updates when we start generating results from our hard-won field data.

This dolphin has a well-marked dorsal fin, which we will match against thousands of photographs in our database. This photo was taken under research permit with a telephoto lens and cropped.
This dolphin has a well-marked dorsal fin, which we will match against thousands of photographs in our database. This photo was taken under research permit with a telephoto lens and cropped.

Counting and protecting Amazon river dolphins

by oceansadminConservation, Dolphins, Ecosystems, Habitat, PopulationsPosted on One Comment

Did you know two species of river ‪dolphin‬ live in the ‪Amazon‬? The pink one is called ‪boto‬, or Inia; the grey one is called ‪tucuxi‬, or Sotalia. Both are gorgeous, ancient species that have become adapted to live their entire lives in freshwater. They are also incredibly tough to spot in muddy waters, and have a cryptic behaviour that makes them difficult to count.

That’s a problem, because a key task in‪ ‎conservation‬ ‪science‬ is knowing whether a species is increasing or decreasing.

We partnered with scientists at Fundación Omacha, University of St Andrews & NOAA to survey river dolphins in a stretch of the Amazon at the border of‪ Colombia‬ & ‪Peru‬. Using some simple field methods [learn more about our small-boat survey toolkit here] & fairly sophisticated analytical methods, we found that tucuxi is likely to be stable or increasing, but boto are likely to be declining.

Our findings are worrisome, given reports from‪ Brazil‬ that there is a major problem with deliberate killing of boto for bait in a lucrative catfish fishery. Our next steps are to (a) continue surveys withFundación Omacha to improve our understanding of seasonal and annual trends; and (b) work with Dr Fernando Trujillo (founder of Omacha) to identify solutions. If poaching is the problem, we can work toward finding alternative sources of fish bait. Dr Trujillo points out that more than 150 major hydroelectric dams are proposed for Amazonia. These would fragment dolphin habitat, and our research shows that we have very low statistical power to detect declines — possibly until they become irreversible.

Want to learn more?

Please check out our video describing the project and showing the animals swimming through flooded rainforest (underwater footage courtesy BBC Natural History Unit).  Science Magazine wrote a news article describing our work — a first for our team.  And of course, let us know if you’d like to read the original, technical paper published in Biological Conservation. 

Happy Spring!

by oceansadminAcoustics, Dolphins, Ocean NoisePosted on No Comments

“In the spring, at the end of the day, you should smell like dirt.”
― Margaret Atwood, Bluebeard’s Egg

It’s officially spring!  Cherry blossoms are a sure sign that spring has sprung in the Pacific Northwest.  But for Pacific white-sided dolphins, spring means herring.  Each spring, Pacific herring find their way to inlets and coastal areas to spawn, laying tens of thousands of eggs.  This dramatic event attracts birds, sea lions, and dolphins.  We were lucky enough to capture footage of Pacific white-sided dolphins working together to corral herring.  Dolphins require a quiet ocean to both to find their prey and to avoid predators like killer whales.  Stay tuned for the results of our investigation to assess which areas along the BC coast are quietest for dolphins.  Hope you enjoy!

The world’s biggest dolphin eating the world’s coolest dolphin

by oceansadminDolphins, Whales, Women in SciencePosted on 2 Comments

During a seemingly ordinary fall day with dolphins,  I captured killer whales attacking and eating a dolphin on film.  It inspired me to devote a chapter of my PhD to killer whale predation on dolphins and the incredibly dynamic interaction unfolding between an intelligent, efficient predator and its similarly intelligent prey.  I’m hooked.  There is so much to learn about this process.  Our colleagues have written very cool papers describing how mammal-eating killer whales attack and kill their prey:  here’s one and here’s another.  And someone has just posted another cool video of dolphins and killer whales off Hyacinthe Island.  We’ve been trying to track down whoever shot that video so we can compare notes.  If you know who they are, could you please put us in touch?  Thanks!

The Pacific white-sided dolphins we study are engaged in a daily struggle between finding food and avoiding being eaten.  Some days are better than others.  If you look in any field guide to marine mammals, you’ll find that Pacific white-sided dolphins are supposed to be an offshore, open-ocean species.  We think these dolphins are here, in the inshore waters of British Columbia off northeastern Vancouver Island, in part to take advantage of fairly reliable food sources like herring and other small, schooling fish.  We also think that chasing fish in these parts carries a serious risk.  Death.  This area is known for reliably seeing resident, salmon-eating killer whales, but the inlets that the dolphins use are also prime hunting spots for mammal-eating, transient or Bigg’s killer whales.

A lot of the work we do is to understand the choices that these dolphins make between finding food and avoiding predators.  While dolphins may not avoid predation altogether, they might have some behaviors up their sleeves that allow them to survive in habitat where predators could be around every corner.  Maybe they cut their foraging a bit short here and there, or keep quiet to elude detection by the killer whales highly-evolved sensory systems.  But smart as dolphins are, they’re not going to 100% effective at avoiding predators.  And hey:  killer whales (OK, you know that killer whales are the biggest member of the dolphin family, right?) have to eat, too.