Pacific white-sided dolphin dorsal fin photos and breath samples

by oceansadminDolphins, Populations, Wildlife Health, Women in SciencePosted on No Comments

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.

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.

Please help us keep orca habitats clean, quiet, and full of fish

by oceansadminAcoustics, Conservation, Habitat, Killer Whale Conservation, Ocean Noise, Populations, Protecting Species, WhalesPosted on No Comments

 

 

The critically endangered southern resident killer whale population now numbers 74 individuals. The ability of the population to recover is hindered by a perfect storm of threats—not enough salmon, too much noise, and toxic chemicals affecting calf survival—but lack of access to salmon is at the eye of that storm.

We need to recover Chinook salmon stocks throughout the whales’ range. 

We support all efforts to do so. We support dam removal, where this will get more salmon into the environment. We applaud the recent announcement to reduce salmon fishing quotas until the whales recovery, which will reduce our competition with the whales. While we wait for those measures to take effect, we need your help to give the whales a fighting chance to find as many of those salmon as possible in a noisy ocean.

We need to give the whales a quiet place to hunt for salmon

Our work has shown that killer whales spend 18-25% less time feeding on salmon when boats are around than when they are undisturbed. We have found that the southern resident killer whale population needs 662 big, fat Chinook salmon each day. We have found that mothers with calves need 43% more calories, more salmon, than adult females without calves.

A protected area can help the whales if we put it in the right place. 

We have found that killer whales are more vulnerable to disturbance when they are feeding than when they are travelling from A to B. They also need more salmon. We have identified areas that whales use preferentially for feeding. (One is called Salmon Bank. We have a feeling the whales knew this before people did.) We need to bring together all dedicated datasets we can use to identify areas where the whales are finding salmon, so we can prioritize those for protection. Protecting key feeding areas is essential to protecting the whales.

Please support our efforts to keep orca habitat clean, quiet, and full of fat, wild salmon.

PS Thanks to our team, especially Toby Hall, for the great footage, and to our friends at SeaLegacy for help editing this video.

One fish, two fish

by oceansadminAnimal Counting Toolkit, PopulationsPosted on No Comments
Our Animal Counting Toolkit offers open-access data and tools to guide low-cost, small-boat surveys for marine wildlife
Our Animal Counting Toolkit offers open-access data and tools to guide low-cost, small-boat surveys for marine wildlife

Knowing how many animals are in a population is at the cornerstone of many conservation and management decisions. For whales, dolphins & porpoises, ship time to estimate abundance can be prohibitively expensive — often running into the tens of thousands of dollars each day.

We’ve just launched our Animal Counting Toolkit to share some of the lessons we’ve learned over the years in conducting low-cost, small boat surveys for marine mammals in coastal waters. It was a lot of fun to publish this work with our colleagues at University of St Andrews, NOAA, IUCN, CyberTracker, BlueWater GIS, and other NGOs and consulting companies. This is a gentle introduction to designing and conducting a survey to estimate abundance of marine wildlife. It is not a substitute for statistical training, but it should provide a good background for data collection. For data analysis, we strongly recommend joining the Distance Sampling web community and taking the Distance workshops at University of St Andrews. 

We published an open access paper introducing our Animal Counting Toolkit approach. Wherever possible, the approach prioritizes free software and tools. Our audience is the community of marine naturalists and scientists who may need a bit of guidance to ensure that their observations could be turned into a useful biodiversity monitoring program. We hope the Toolkit finds an audience among NGOs, grad students, coastal communities, and researchers working in countries where funding is severely limited. The US just passed a rule requiring countries to demonstrate that their fisheries are sustainable in terms of marine mammal bycatch. This rule affects $20 billion/year in seafood trade. It is driven in part by a need to level the playing field for US fisheries that have to comply with the Marine Mammal Protection Act and are competing with fisheries that are not MMPA-compliant. Used wisely, the new trade rule will use the purchasing power of the US market to create incentives to improve fisheries sustainability and transparency. But if it is imposed too harshly, and without funding for low-income countries to comply, the US risks penalizing countries that can least afford to take an economic hit. Our Animal Counting Toolkit was motivated in part by this new rule. We want to fill in important data gaps around the world, but we also see value in using this toolkit to help build local and regional capacity for countries to begin to do the kind of surveys that will be needed to demonstrate compliance with this new seafood trade rule. Our hope is to see countries actually improve sustainability of their fisheries, so that we reduce the number of marine mammals killed in fisheries while improving economic opportunities for people who earn their living from the sea.

Telling stories about wildlife populations, one photograph at a time

by oceansadminDolphins, Populations, Women in SciencePosted on One Comment

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.
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.

Natalie Mastick

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.