Oceans Initiative is proud to share that our Executive Director and Senior Scientist Dr. Erin Ashe was featured in a recent issue of Canadian Geographic magazine. The article: “A labour of love: Using photo-identification to track Pacific white-sided dolphins” discusses Erin’s long-term research to better understand this species. In fact, Erin has been studying Pacific white-sided dolphins in Canada’s Broughton Archipelago since 2005 and has devoted much of her work to protecting this population of dolphins. We hope you’ll take a few minutes to enjoy the article.
Dolphins have the ability to draw people in to really appreciate and connect with nature — and I think that’s something we all need right now more than ever.
Exploring Dynamics of Abundant Dolphin Populations Under Uncertainty
Our co-founder Dr. Erin Ashe’s latest publication, Minding the Data-gap Trap, has been published in Frontiers in Marine Science.
Yes, we must focus on endangered species, but we mustn’t lose sight of the apparently common species that are under the radar. We risk losing those species through neglect and apathy. Biodiversity conservation needs to protect the abundant species that hold ecosystems together, and also the rare species we can’t afford to lose. Turns out, you can use what you know about basic life-history of data-poor species, and the threats they face, to prioritize species for research funding and management actions.
This interdisciplinary paper was published with colleagues from IUCN, Curtin University, Cornell University Cornell Lab of Ornithology, University of St Andrews, Arizona State University, Brookfield Zoo, and Smithsonian.
“It’s always such a privilege to study marine wildlife. I am especially grateful to join Oceans Initiative in their research with Pacific white-sided dolphins in truly one of the most beautiful places on Earth.”
— Laura Bogaard
This summer marks our 11th year of Pacific white-sided dolphin research in the Broughton Archipelago of British Columbia, Canada. Since the birth of this project with Dr. Erin Ashe’s PhD research, we have learned so much about this fascinating and under-studied species. The Broughton Archipelago also provides a rare opportunity to study a generally pelagic (open ocean) species in inshore waters. We now think that this habitat may be crucial to their feeding on herring. It also acts as a nursery for rearing their babies. The initial goal of our study was to use dorsal fin photographs for identification to model population level changes from year to year. You can read more about the post-season intricacies of this work from Natalie Mastick’s blog post on our website.
It’s a 3-day trip on our research vessel, Wishart, from Seattle to Malcolm Island in British Columbia. On the way, we stopped briefly at San Juan Island to check in on our Southern Resident killer whale field team. As we navigated up the inside waters between Vancouver Island and the mainland of British Columbia, we spotted a plethora of marine mammal species including humpback whales, transient killer whales, harbor seals, harbor porpoise, Dall’s porpoise, and Steller sea lions.
We were also delighted to be joined for a few days by Ryan Tidman and Chelsea Xavier-Blower of SeaLegacy. They brought lots of creative energy (and of course, their drones) and helped us with building some fun new behind the scenes content that we are very excited to share on social media in the upcoming months.
Photo credit: Ryan Tidman
The two action-packed weeks that followed covered three research aims: investigate the effectiveness of a fishing pinger on dolphin avoidance behavior, collect breath samples in order to better understand their individual health, and capture as many identification photographs as possible. We collected almost 700 GB of identification photos and 17 breath samples, and conducted 30 experimental trials for our pinger study. Satisfied, fulfilled, and exhausted we ended our expedition on a high note.
On our last day in the Broughton, we had a rare opportunity to re-sight my favorite humpback whale, Lucky, whom I wrote about in my first blog post as an intern three summers ago. We even got to watch as she and another humpback were bubble-net feeding! This is where humpback whales blow bubbles in a large circular motion, creating a “net” around a school of fish. Then, they lunge up through the school, mouths open wide, gulping large quantities of prey.
It is always such a privilege to study marine wildlife. I am especially grateful to join the Oceans Initiative team in one of the most beautiful places in the world.
In August, part of our team traveled to the Broughton Archipelago off the coast of northern Vancouver Island to continue our long-term study on Pacific white-sided dolphins. This study is multi-faceted. We are studying the health of the population by taking dorsal fin photos for statistical analysis, but we are also studying the health of individuals by looking for pathogens in exhaled breath. We’ve just celebrated the 10th anniversary of this study, but we made a few changes along the way. This year, with the help of Alimosphere, we were able to look at dolphin pods we encountered from a new perspective through the use of Unmanned Aerial Systems (UAS), also known as drones.
Drone footage collected under permit, by Alicia Amerson.
R/V Wishart
This year, we are sponsoring our research associate, Natalie Mastick, to start an exciting PhD project in marine parasite ecology. As she explains in a recent blog post, taking photos of dorsal fins is a non-invasive way to study the population that allows us to identify individuals that we can use as statistical samples in models to estimate survival rates, and population size and trends. High-resolution dorsal fin photographs show us distinguishable details such as nicks, scars, and markings that help us to recognize individuals from year to year. The Pacific white-sided dolphin study launched by our co-founder, Dr Erin Ashe, has involved taking, processing and matching dorsal fin photos to previous catalogues since 2007. Some individuals have been seen in the study area since the 1990s, and we have seen one pair of dolphins together on two occasions 17 years apart.
Laurel Yruretagoyena, Oceans Initiative research assistant, aiding Dr Erin Ashe in taking dorsal fin photos for her long-term photo ID study. Look closely, like deckhand Molly Brown is doing, and you’ll see some dorsal fins in the distance! Photo credit: Laura Bogaard, 2018.
As a continuation of a study started by Erin in 2015, we also spent much of our time collecting exhaled breath samples from these dolphins. We collect breath samples by positioning a long pole with a petri dish attached to one end over a dolphin as it surfaces and exhales. This is a tricky activity that involves a knowledge of dolphin surfacing patterns, careful boat handling, precise timing, and skillful maneuvering on the bow of the boat. Despite the difficulty, our team was able to collect many breath samples that we will use to assess the pathogens (e.g., viruses, bacteria and fungi) this population has been exposed to. Ultimately, we aim to let the health of the dolphins tell us something about the health of their environment. Understanding how pollutants impact marine mammals and their habitat is essential to informing recovery efforts and monitoring ecosystem health.
A beautiful crisp morning spent with energetic Pacific white-sided dolphins off Vancouver Island. Photo credit: Dr Erin Ashe, 2018.
Next year, we are hoping to invite Alicia Amerson from Alimosphere to the Pacific Northwest to join us in the field again for a workshop on using UAS for noninvasive marine mammal research. We aim to offer this opportunity to other women in marine mammal science, and to our entire staff. We hope this will provide us with a new tool for collecting breath samples in the future, in a continuation of our efforts to use minimally invasive field research techniques. As we close out our field season, we are so thankful for the support we have received to do this important work.
Guest post from our newest team member, Natalie Mastick
“I look at pictures of dolphins all day,” is my most common answer when asked what I do for work.
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.
It’s an over-simplified statement, albeit accurate, and it usually leads to many follow-up questions. The most frequent being “Why?” That’s a fair question. I then proceed to explain how by looking at photos of the dorsal fins of dolphins, I can identify individuals, which can be used in calculating population estimates and survival rates. I am usually surprised by the awe that this explanation inspires, as I am somewhat numb to the task after several months of photo analysis. “You can really tell dolphins apart like that?” They have a point; photo-identification is quite remarkable when you think about it.
Photo-identification (photo-ID for short) is a non-invasive way to study marine mammal populations. It’s been used for both cetaceans (dolphins and whales) and pinnipeds (seals and sea lions), and requires a high-resolution photo of each individual. Photo-ID is an effective way to determine individuals based on coloration, markings, scars, fin shape, nicks and notches. For humpback whales, the underside of the fluke is the most recognizable feature, which is can be photographed as the whale dives. For dolphins, one of the most recognizable features is an individual’s dorsal fin, visible as the dolphin breathes at the surface.
I have worked on several projects that use photo-ID, including a long-term study of bottlenose dolphins in Florida, humpback whale population analysis in Antarctica, and currently, a long-term study of Pacific white-sided dolphins in British Columbia with Oceans Initiative. To accomplish this work takes three major steps: photographing wild dolphins, processing the photos, and then looking for matches between the photos.
Oceans Initiative has been taking photos of these dolphins since 2007, which is not an easy feat. Pacific white-sided dolphin are fast and can often travel in large pods of hundreds of animals. Erin, Rob, and their dedicated field team have a ton of experience taking photos of these animals, which provided me with a hearty collection of over 10,000 photos to process. One by one, I went through and determined the quality of each photo. Obviously when photographing hundreds of dolphins quickly surfacing and diving, not every photo will be useable for a photo-ID catalog. I found the photos in which fins were in focus, parallel with the camera, and mostly visible (not partly submerged or covered by water or other dolphins) and then looked carefully at each fin to determine its distinctiveness.
It never ceases to amaze me how different dolphin fins can look. A dolphin can have a single little notch at the base of its fin that makes it completely distinct from the rest of the dolphins seen that day. The combination of scarring, nicks from other dolphins, entanglements, killer whales, and normal wear and tear provide an endless permutation of unique fins. I visually assessed each high-quality photo and determined if the fin was not distinctive, somewhat distinctive by temporary marking or discoloration, moderately distinctive, or highly distinctive. Moderately and highly distinctive fins can be used to identify an individual over longer temporal scales.
Once the fins were scored for distinctiveness, it was then my job to match them to other fins within that encounter, and lastly between encounters from that season. When matching between a single encounter, it’s a lot like a game of memory. You know you’ve seen that fin before, you just need to remember where in order to match them. Once the fins are matched within an encounter, I compile a “best of” folder with all of the identifiable individuals observed in that area to match to the other encounters.
When you include the variable of time, then it becomes more like a game of 6 differences, in which you need to spot what’s changed in a fin over time. Except instead of having two fins that you know are just slightly different versions of the same fin that you’re comparing side-by-side, you need to look through the entire catalog to determine if a fin has actually changed since last identified or if it’s a new individual. Though that’s a fun challenge, it is unlikely that a fin changes much over the course of a few weeks, which means matching fins across encounters is a little easier than across years.
To match fins across encounters, I compile all of the moderately and highly distinctive fins from each encounter and look for individuals seen more than once. The 2016 field season provided over 1000 identifiable photos, which were then compared to each other to determine if there were matches. This is where your imagination comes into play. Looking at these fins enough, you start to see shapes in the nicks and notches and fin shape. There was a fin with a distinctive nick towards the top that looked like the profile of a person yelling. There was another that looked remarkably like a bicep. There was one photo in which a fin caught the light just right and looked like it was reflecting back the shape of a storm trooper.
Reading that back sounds like I’ve kind of lost it. Looking at fins enough might do that to you! But overall, being able to put a minimum number to the dolphins seen last season (think about all the dolphins we couldn’t photograph and the fins that weren’t distinctive enough to match!) is incredibly rewarding, and completing each step of the processing myself was oddly satisfying. I’m hoping we can get a comparable number of photos in 2017, and look forward to seeing some familiar fins in the field.
