Leigh Torres – Page 5 – Geospatial Ecology of Marine Megafauna Laboratory

GEMM Lab 2019: A Year in the Life

By Lisa Hildebrand, MSc student, OSU Department of Fisheries & Wildlife, Geospatial Ecology of Marine Megafauna Lab

Another year has come and gone, and with the final days of 2019 upon us, it is fulfilling to look back and summarize all of the achievements in the GEMM Lab this year. So, snuggle up with your favorite holiday drink and enjoy our recap of 2019!

We wrapped up two intense but rewarding gray whale field seasons this summer. Our project investigating the health of Pacific Coast Feeding Group (PCFG) gray whales through fecal hormone and body condition sampling in the context of ocean noise went into its fourth year, while the Port Orford project where we track whales and prey at a very fine-scale celebrated its wood anniversary (five years!). The dedication and hard work of lots of people to help us collect our data meant that we were able to add a considerable amount of samples to our growing gray whale datasets. Our trusty red RHIB Ruby zipped around the Pacific and enabled us to collect 58 fecal samples, fly the drone 102 times, undertake 105 GoPro drops and record 141 gray whale sightings. Our Newport crew was a mix of full-time GEMMers (Leigh, Todd, Dawn, Leila, Clara, and myself) as well as part-time summer GEMMers (Ale, Sharon, and Cassy). Further south in Port Orford, my team of undergraduate and high school students and I had an interesting field season. We only encountered four different individuals (Buttons, Glacier, Smudge, and Primavera), however saw them repeatedly throughout the month of August, resulting in as many as 15 tracklines for one individual. Furthermore, we collected 249 GoPro drops and 248 zooplankton net samples.

Leila taking photos of gray whales from Ruby’s bow pulpit. Photo: Leigh Torres

The GEMM Lab’s fieldwork was not just restricted to gray whales. After last year’s successes aboard the NOAA ship Bell M. Shimada, Alexa and Dawn both boarded the ship again this year as marine mammal observers for the May and September cruises, respectively. They spied humpback, blue, sperm, and fin whales, as well as many dolphins and seabirds, adding to the GEMM Lab’s growing database of megafauna distribution off the Oregon coast.

Alexa observing on the R/V Shimada in May 2019, all bundled up. Image Photo: Alexa Kownacki

After winning the prestigious L’Oréal-UNESCO For Women in Science fellowship and the inaugural Louis Herman Scholarship, GEMM Lab grad Solène Derville lead her first research cruise aboard the French R/V Alis. She and her team conducted line transect surveys and micronekton/oceanographic sampling over several seamounts to try to solve the mystery of why humpbacks hang out there. We are also very excited to announce that Solène will be returning to the GEMM Lab as a post-doc in 2020! She will be creating distribution models of whales off the coast of Oregon with the data collected by Leigh during helicopter flights with the US Coast Guard. The primary aim of this work is to identify potential whale hotspots in an effort to avoid spatial overlap with fisheries gear and reduce entanglement risk.

Solène soaking wet after spending several hours observing cetaceans and seabirds on R/V Alis. Photo: Jérôme Jambou

Switching the focus from marine mammals to seabirds, Rachael has had an extremely busy year of field work all across the globe. She island-hopped from Midway (Hawaiian Northwest island) to the Falkland Islands in the first half of the year, and is currently overwintering on South Georgia, where she will be until end of February. Rachael is tracking albatross at all three locations by tagging individual birds to understand movements relative to fishing vessels and flight energetics.

Besides several field efforts, the GEMM Lab was also busy disseminating our research and findings to various audiences. Our conferences kicked off in late February when Leigh and Rachael both flew to Kauai to present at the Pacific Seabird Group’s 46^th Annual Meeting. In the spring, Leila, Dawn, Alexa, Dom, and myself drove to Seattle where the University of Washington hosted the Northwest Student Society of Marine Mammalogy chapter meeting and we all gave talks. Additionally, the Fisheries & Wildlife grad students in the lab also presented at the department’s annual Research Advances in Fisheries, Wildlife, and Ecology conference. Later in the year, Dom and I attended the State of the Coast conference where Dom was invited to participate in a panel about the holistic approaches to management in the nearshore while I presented a poster on preliminary findings of my Master’s thesis. Most recently, the entire GEMM Lab (bar Rachael) flew to Barcelona to present at the World Marine Mammal Conference (WMMC).

GEMM Lab at the WMMC. Photo: Karen Lohman

Our science communication and outreach efforts were not just restricted to conferences though. Over the course of this year, the GEMM Lab supervised a total of 10 undergraduate and high school interns that assisted in a variety of ways (field and/or lab work, data analyses, independent projects) on a number of projects going on in the lab. Leigh and Dawn boarded the R/V Oceanus in the fall to co-lead a STEM research cruise aimed at providing high school students and teachers hands-on marine research. Dawn and I were guests on Inspiration Dissemination, a live radio show run by graduate students about graduate research going on at OSU. Our weekly blog, now in its fifth year, reached its highest viewership with a total of 14,814 views this year!

The GEMMers were once again prolific writers too! The 13 new publications in 10 scientific journals include contributions from Leigh (7), Rachael (6), Solène (2), Dawn (2), and Leila (1). Scroll down to the end of the post to see the list.

Academic milestones were also reached by several of us. Most notably and recently, Dom successfully defended his Master’s thesis this past week – congratulations Dom!! Unsurprisingly, he already has a job lined up starting in January as a Science Officer with the California Ocean Science Trust. Dom is the 6^th GEMM Lab graduate, which after just five years of the GEMM Lab existing is a huge testament to Leigh as an advisor. Leila, who is in the 4^th year of her PhD, anticipates finishing this coming March. We also had three successful research reviews – I met with my committee in late March to discuss my Master’s proposal, while Alexa and Dawn met with their committees in the summer to review their PhD proposals. All three reviews were fruitful and successful. And we want to highlight the success of a GEMM Lab grad, Florence Sullivan, who started a job in Maui with the Pacific Whale Foundation in September as a Research Analyst.

Dom during his MS seminar. Photo: Leila Lemos

Leigh was recognized for her expertise in gray whale ecology and was appointed to the IUCN Western Gray Whale Advisory Panel (WGWAP). The western gray whales are a critically endangered population. At one point in the 1960s, the population was so scarce that they were believed to have been extinct. While this concern did not prove to be the case, the population still is not doing well, which is why the IUCN formed WGWAP to provide advice on the conservation of the western gray whales. Leigh was appointed to the panel this year and traveled to Switzerland and Russia for meetings.

Clara aboard Ruby on her first day of gray whale field work in Oregon. Photo: Leigh Torres

We are excited about a new addition to the lab. Clara Bird started her MS in Wildlife Science in the Department of Fisheries & Wildlife this fall. She jumped straight into field work when she came in early September and got a taste of the Pacific. Clara joins us from the Duke University where she did her undergraduate degree and worked for the past year in their Marine Robotics and Remote Sensing Lab. Clara is digging into the gray whale drone footage collected over the last four field seasons and scrutinize them from a behavioral point of view.

If you are reading this post, we would like to say that we really appreciate your support and interest in our work! We hope you will continue to join us on our journeys in 2020. Until then, happy holidays from the GEMM Lab!

GEMM Lab at the beginning of June with some permanents GEMMs and some temporary summer GEMM helpers.

Barlow, D. R., M. Fournet, and F. Sharpe. 2019. Incorporating tides into the acoustic ecology of humpback whales. Marine Mammal Science 35:234-251.

Barlow, D. R., A. L. Pepper, and L. G. Torres. 2019. Skin deep: an assessment of New Zealand blue whale skin condition. Frontiers in Marine Science doi.org/10.3389/fmars.2019.00757.

Baylis, A. M. M., R. A. Orben, A. A. Arkhipkin, J. Barton, R. L. Brownell Jr., I. J. Staniland, and P. Brickle. 2019. Re-evaluating the population size of South American fur seals and conservation implications. Aquatic Conservation: Marine and Freshwater Ecosystems 29(11):1988-1995.

Baylis, A. M. M., M. Tierney, R. A. Orben, et al. 2019. Important at-sea areas of colonial breeding marine predators on the southern Patagonian Shelf. Scientific Reports 9:8517.

Cockerham, S., B. Lee, R. A. Orben, R. M. Suryan, L. G. Torres, P. Warzybok, R. Bradley, J. Jahncke, H. S. Young, C. Ouverney, and S. A. Shaffer. 2019. Microbial biology of the western gull (Larus occidentalis). Microbial Ecology 78:665-676.

Derville, S., L. G. Torres, R. Albertson, O. Andrews, C. S. Baker, P. Carzon, R. Constantine, M. Donoghue, C. Dutheil, A. Gannier, M. Oremus, M. M. Poole, J. Robbins, and C. Garrigue. 2019. Whales in warming water: assessing breeding habitat diversity and adaptability in Oceania’s changing climate. Global Change Biology 25(4):1466-1481.

Derville, S., L. G. Torres, R. Dodémont, V. Perard, and C. Garrigue. 2019. From land and sea, long-term data reveal persistent humpback whale (Megaptera novaeangliae) breeding habitat in New Caledonia. Aquatic Conservation: Marine and Freshwater Ecosystems 29(10):1697-1711.

Fleischman, A. B., R. A. Orben, N. Kokubun, A. Will, R. Paredes, J. T. Ackerman, A. Takahashi, A. S. Kitaysky, and S. A. Shaffer. 2019. Wintering in the western Subantarctic Pacific increases mercury contamination of red-legged kittiwakes. Environmental Science & Technology 53(22):13398-13407.

Holdman, A. K., J. H. Haxel, H. Klinck, and L. G. Torres. 2019. Acoustic monitoring reveals the times and tides of harbor porpoise (Phocoena phocoena) distribution off central Oregon, U.S.A. Marine Mammal Science 35:164-186.

Kroeger, C., D. E. Crocker, D. R. Thompson, L. G. Torres, P. Sagar, and S. A. Shaffer. 2019. Variation in corticosterone levels in two species of breeding albatrosses with divergent life histories: responses to body condition and drivers of foraging behavior. Physiological and Biochemical Zoology 92(2):223:238.

Loredo, S. A., R. A. Orben, R. M. Suryan, D. E. Lyons, J. Adams, and S. W. Stephensen. 2019. Spatial and temporal diving behavior of non-breeding common murres during two summers of contrasting ocean conditions. Journal of Experimental Biology and Ecology 517:13-24.

Monteiro, F., L. S. Lemos, J. Fulgêncio de Moura, R. C. C. Rocha, I. Moreira, A. P. Di Beneditto, H. A. Kehrig, I. C. A. C. Bordon, S. Siciliano, T. D. Saint’Pierre, and R. A. Hauser-Davis. 2019. Subcellular metal distributions and metallothionein associations in rough-toothed dolphins (Steno bredanensis) from southeastern Brazil. Marine Pollution Bulletin 146:263-273.

Orben, R. A., A. B. Fleischman, A. L. Borker, W. Bridgeland, A. J. Gladics, J. Porquez, P. Sanzenbacher, S. W. Stephensen, R. Swift, M. W. McKown, and R. M. Suryan. 2019. Comparing imaging, acoustics, and radar to monitor Leach’s storm-petrel colonies. PeerJ 7:e6721.

Yates, K. L., …, L. G. Torres, et al. 2019. Outstanding challenges in the transferability of ecological models. Trends in Ecology & Evolution 33(10):790-802.

Flying halfway around the world to learn about marine mammals from around the world!

By Lisa Hildebrand, MSc student, OSU Department of Fisheries & Wildlife, Geospatial Ecology of Marine Megafauna Lab

The GEMM Lab is back from Barcelona after attending the World Marine Mammal Conference last week and it sure was a week to remember! Not only did every GEMM member present some aspect of their research at the conference (either as a poster, speed or full-length talk) but some of us also attended workshops, scheduled meetings with collaborators, new & old, and we certainly all learned a lot of new information about what is going on in marine mammalogy across the globe. Having had a few days now to reflect upon the intense four days spent at the conference, we want to highlight the talks that we each personally thought were some of the most interesting and exciting.

“Double Drone Drama” was the alliterative title of Héloïse Frouin-Mouy‘s talk about using two drones to collect simultaneous visual and underwater acoustic behavioral data of gray whales in Baja California, Mexico. While there were many talks during the week that discussed incorporating drones, also known as unmanned aerial vehicles (UAVs), into marine mammal research, this project was potentially the only one that discussed using two simultaneously. One drone collected visual aerial observations while the other obtained close-range passive acoustic measurements with an underwater recording hydrophone to better understand the behavioral contexts of call generation. Froiun-Mouy and her team detected call-type-specific source levels relative to behavior state through this dual-approach. For example, they were able to estimate the acoustic source levels of bubble-blasts produced by gray whales, and the double drone action recorded a variety of calls. Using two or more UAVs can provide a more integrated snapshot into the animal vocalization context, and it will be interesting to see whether this method is applied elsewhere on a variety of whale species.

Tara Sayuri Whitty. Source: UCSD Aquarium.

Tara Sayuri Whitty discussed her doctoral research focused on understanding the mental models of local, artisanal fishing communities at the heart of the vaquita conservation efforts. The vaquita has experienced rapid population declines due primarily to bycatch in gillnet fisheries from legal local gillnet fisheries and the illegal totoaba fishery. With the sole intent of preventing bycatch, gillnets were banned for legal practice, but the illegal totoaba fishery continued, as did vaquita bycatch. Whitty conducted interviews to understand the mental models and perceptions of local fishing communities towards officials and conservationists regarding the gillnet band. She discovered that these conservation efforts have not only failed to prevent vaquita bycatch, but they have now pitted conservationists against local communities because an important aspect of their livelihoods is now banned. This misstep and lack of trust with the community now threatens future conservation and recovery progress for the vaquita and highlights the need to collaborate and engage with local communities early and often when such efforts are so closely tied to human well-being.

Pauline Goulet, a PhD student in the Sea Mammal Research Unit at the University of St. Andrews, presented findings obtained from a novel sonar tag deployed on southern elephant seals (SES) in the Kerguelen Islands and Peninsula Valdes. Gaining insight into predator-prey interactions is critical to understanding the ecology of marine mammals as they live in dynamic and vast environments where prey is patchy. Collecting in-situ prey information is difficult, and in some cases impossible, due to the remote locations where marine mammals forage and it is not being feasible to follow individuals around continuously to collect prey samples at every foraging event. In an attempt to overcome this universal challenge to marine mammal research, Goulet and her collaborators decided to mimic the experts in prey detection and visualization from a distance in the marine environment – echolocating odontocetes. By equipping conventional DTAGs with a 1.5 MHz single beam sonar with a 6 m detection range, Goulet was able to identify whether SES were pursuing individual fish or large schools of fish. Additionally, by also analyzing the accelerometer data, she could document whether prey capture attempts were successful or not, and link these results to the body condition of individual SES (inferred from the horizontal distance an individual traveled during drift dives, whereby a longer horizontal distance in the same period of time suggested that the individual had gained weight and was now heavier). It was ingenious to see researchers utilize a biological trait that evolved millions of years ago in certain marine mammal predators to better understand the ecology of another marine mammal predator.

A trio of talks given by Kristi Fazioli, Valeria Paz, and Shauna McBride-Kebert, in the ‘Habitat and Distribution II’ session, discussed responses of coastal bottlenose dolphins to hurricanes in the Gulf of Mexico (GoM). Besides continuing to be an area of interest in conservation after the Deepwater Horizon oil spill, the GoM frequently experiences hurricanes and other strong storm systems that cause extensive flooding events annually. Hence, dolphins along the GoM coast experience a large outflow of freshwater after severe precipitation, leading to low salinity events. Both Fazioli and Paz hypothesized that these changes in environmental conditions can create health problems to the dolphins.

Bottlenose dolphin underwater in the Gulf of Mexico. Source: Mike Heithaus.

Fazioli investigated encounter rates and skin conditions of bottlenose dolphins after Hurricane Harvey. She found that, in 2017, the encounter rates in her study area decreased, while skin lesions increased (Christina Toms, unpublished work, expected Spring 2020). Skin lesions are known to occur at higher rates after exposure to freshwater and even though they persist for some time, they eventually do heal. After less than two years, preliminary data suggest that these dolphins have returned to their original distributions in the study area. Paz’s study in Shark Bay Estuary examined different environmental drivers of dolphin distribution following Hurricane Irma. She found that dissolved oxygen, salinity, and temperature were the primary dynamic, environmental drivers of distribution following a major hurricane. Lastly, McBride’s species distribution models of bottlenose dolphins in response to severe flooding concluded that depth, slope, latitude, longitude, season, and dissolved oxygen all contributed in different percentages to distribution.

Marta Guerra presented findings from her PhD research at the University of Otago in New Zealand on the ecology and distribution of sperm whales in New Zealand. Kaikoura canyon is a region utilized by sperm whales for foraging, and Marta’s research highlighted marked differences in their distribution between the summer and winter, likely reflective of the sperm whales switching their target prey items seasonally. In the middle of their data collection period, a very intense earthquake struck the region in 2016, causing a canyon-flushing event that altered the canyon ecosystem. The sperm whales responded to this extreme event by altering their distribution away from the areas most affected by the earthquake, demonstrating that these marine predators respond to environmental shifts in the ecosystem they depend on at multiple scales.

On the final day of the conference, David Wiley gave a talk entitled “First documentation of coordinated bottom-feeding by humpback whales”. Using footage from tags containing a suite of sensors and video cameras, Wiley and colleagues observed humpback whales feeding on sand lace in the Stellwagen Bank National Marine Sanctuary. Sand lace are a species of fish that frequently burrow in the sand in an attempt to avoid capture by predators looking for their next meal. Humpback whales in the area have been observed with lacerations and scars along their mouths, originally leading to the hypothesis that whales were bottom-feeding. However, it was never known whether whales compete or cooperate when exploiting this resource and what the actual mechanics of this feeding behavior look like. The tag data revealed that groups of 3-4 individuals work together to approach the seafloor in a star-shape formation and when they get close enough, the sand lace emerge from the sand (probably an escape response to the approaching vibrations created by large whales) only to be engulfed by the humpbacks who are poised directly above them with wide-open mouths. Not only did the video footage reveal that individuals are so close together that their rostrums are almost touching, but Wiley and team were able to determine that whales perform their behavior usually within the same group of 3-4 individuals and that the orientation of each individual within the star-formation remains the same almost every time. This talk was so enjoyable because it was a reminder of how little we still know about marine mammals and provided a moment of audible awe and surprise throughout the room.

Barcelona-bound! The GEMM Lab heads to the World Marine Mammal Conference

By Dawn Barlow, PhD student, OSU Department of Fisheries and Wildlife, Geospatial Ecology of Marine Megafauna Lab

Every two years, an international community of scientists, managers, policy-makers, educators, and students gather to share the most current research and most pressing conservation issues facing marine mammals. This year, the World Marine Mammal Conference will take place in Barcelona, Spain from December 7-12, and the whole GEMM Lab will make their way across the Atlantic to present their latest work. The meeting is an international gathering of scientists ranging from longtime researchers who have shaped the field throughout the course of their careers to students who are just beginning to carve out a niche of their own. This year’s conference has 2,500 registered attendees from 95 different countries, 1,960 abstract submissions, and 700 accepted oral and speed talks and 1,200 posters. Needless to say, it is an incredible platform for learning, networking, and putting our work in the context of research taking place around the globe.

This will be my third time at this conference. I attended in San Francisco in 2015 as a wide-eyed undergraduate and met with Leigh, who I hoped would soon become my graduate advisor. I also presented my Masters research at the conference in Halifax in 2017. This time around, I will be presenting findings from the first two chapters of my PhD. Looking ahead to the Barcelona 2019 meeting and having some sense of what to expect, I feel butterflies rising in my stomach—a perfect mixture of the nerves that come with putting your hard work out in the world, eagerness to learn and absorb new information, and excitement to reconnect with friends and colleagues from around the world. In short, I can’t wait!

For those of you reading this blog that are unable to attend, I’d like to share an overview of what the GEMM Lab will be presenting at the conference. If you will be in Barcelona, we warmly invite you to the following posters, speed talks, and oral presentations! In order of appearance:

What do Oregon gray whales like to eat? Do individual whales have individual foraging habits? To learn more visit Lisa Hildebrand’s poster “Investigating potential gray whale individual foraging specializations within the Pacific Coast Feeding Group”. (Poster presentation, Session: Foraging Ecology – Group A, Time: Monday, 1:30-3:00pm)

Todd Chandler, Faculty Research Assistant

Did you know it is possible to measure the mechanics of how a blue whale feeds using a drone? The GEMM Lab’s all-star drone pilot Todd Chandler will present a poster titled “More than snacks: An analysis of drone observed blue whale surface lunge feeding linked with prey data”. (Poster presentation, Session: Foraging Ecology – Group A, Time: Monday, 1:30-3:00pm)

The GEMM Lab’s newest student Clara Bird will present a poster on work she conducted with the Marine Robotics and Remote Sensing lab at Duke University using new technologies and approaches to investigate scarring patterns on humpbacks. Her poster is titled “A comparison of percent dorsal scar cover between populations of humpback whales (Megaptera novaeangliae) off California and the Western Antarctic Peninsula”. (Poster presentation, Session: New Technology – Group B, Time: Tuesday, 8:30-9:45am)

Dr. Leigh Torres, Principal Investigator

GEMM Lab PI Leigh Torres will synthesize some exciting new analyses from the GEMM Lab’s gray whale physiology and ecology research off the Oregon Coast. Is it stressful to feed in a noisy coastal environment? Leigh will discuss the latest findings in her talk, “Sounds of stress: Evaluating the relationships between variable soundscapes and gray whale stress hormones”. (Oral presentation, Session: Physiology, Time: Tuesday, 11:30-11:45am)

Carrying on with exciting new findings about Oregon gray whales, Leila Lemos will present a speed talk titled “Stressed and slim or relaxed and chubby? A simultaneous assessment of gray whale body condition and hormone variability”, in which she will summarize three years of analysis of how gray whale health can be quantified, and how physiology is influenced by ocean conditions. (Speed talk, Session: Physiology, Time: Tuesday, 11:55am-12:m)

Can we predict where blue whales will be using our understanding of their environment and prey? Can this knowledge be used for effective conservation? I (Dawn Barlow) will give a presentation titled “Cloudy with a chance of whales: Forecasting blue whale occurrence based on tiered, bottom-up models to mitigate industrial impacts”, which will share our latest findings on how functional ecological relationships can be modeled in changing ocean conditions. (Oral presentation, Session: Habitat and Distribution I, Time: Wednesday, 10:15-10:30am)

Dr. Solene Derville, Post-Doctoral Scholar

The GEMM Lab’s most recent graduate Solene Derville will present work she has conducted in New Caledonia regarding humpback whale diving and movement patterns around breeding grounds. Her speed talk is titled “Whales of the deep: Horizontal and vertical movements shed light on humpback whale use of critical pelagic habitats in the western South Pacific” (Speed talk, Session: Behavioral Ecology II, Time: Wednesday, 11:35-11:40am)

Can sea otters make a comeback in Oregon after a long absence? Dom Kone takes a comprehensive look at how Oregon coast habitat could support a reintroduced sea otter population in his speed talk, “An evaluation of the ecological needs and effects of a potential sea otter reintroduction to Oregon, USA”. (Speed talk, Session: Conservation II, Time: Wednesday, 2:45-2:50pm)

Alexa Kownacki will share her latest findings on dolphin distribution relative to static and dynamic oceanographic variables in her speed talk titled “The biogeography of common bottlenose dolphins (T. truncatus) of the southwestern USA and Mexico”. (Speed talk, Session: Habitat and Distribution II, Time: Wednesday, 3:35-3:40pm)

Other members of the Marine Mammal Mnstitute who will present their work include: Scott Baker, Debbie Steel, Angie Sremba, Karen Lohman, Daniel Palacios, Bruce Mate, Ladd Irvine, and Robert Pitman. For anyone planning to attend, we look forward to seeing you there! For those who wish to stay tuned from home, keep your eye on the GEMM Lab twitter page for our updates during the conference and follow the conference hashtag #WMMC19, and look forward to future blog posts recapping the experience.

What is that whale doing? Only residence in space and time will tell…

By Lisa Hildebrand, MSc student, OSU Department of Fisheries and Wildlife, Geospatial Ecology of Marine Megafauna Lab

For my research in Port Orford, my field team and I track individual gray whales continuously from a shore-based location: once we spot a whale we will track it for the entire time that it remains in our study site. The time spent tracking a whale can vary widely. In the 2018 field season, our shortest trackline was three minutes, and our longest track was over three hours in duration.

This variability in foraging time is partly what sparked my curiosity to investigate potential foraging differences between individuals of the Pacific Coast Feeding Group (PCFG) gray whales. I want to know why some individuals, like “Humpy” who was our longest tracked individual in 2018, stayed in an area for so long, while others, like “Smokey”, only stayed for three minutes (Figure 1). It is hard to pinpoint just one variable that drives these decisions (e.g., prey, habitat) made by individuals about where they forage and how long because the marine environment is so dynamic. Foraging decisions are likely dictated by several factors acting in concert with one another. As a result, I have many research questions, including (but certainly not limited to):

Does prey density drive length of individual foraging bouts?
Do individual whales have preferences for a particular prey species?
Are prey patches containing gravid zooplankton targeted more by whales?
Do whales prefer to feed closer to kelp patches?
How does water depth factor into all of the above decisions and/or preferences?

I hope to get to the bottom of these questions through the data analyses I will be undertaking for my second chapter of my Master’s thesis. However, before I can answer those questions, I need to do a little bit of tidying up of my whale tracklines. Now that the 2019 field season is over and I have all of the years of data that I will be analyzing for my thesis (2015-2019), I have spent the past 1-2 weeks diving into the trackline clean-up and analysis preparation.

The first step in this process is to run a speed filter over each trackline. The aim of the speed filter is to remove any erroneous points or outliers that must be wrong based on the known travel speeds of gray whales. Barb Lagerquist, a Marine Mammal Institute (MMI) colleague who has tracked gray whales for several field seasons, found that the fastest individual she ever encountered traveled at a speed of 17.3 km/h (personal communication). Therefore, based on this information, my tracklines are run through a speed filter set to remove any points that suggest that the whale traveled at 17.3 km/h or faster (Figure 2).

*Fig 3. Trackline of “Humpy” after interpolation. The red points are interpolated.*

Next, the speed-filtered tracklines are interpolated (Figure 3). Interpolation fills spatial and/or temporal gaps in a data set by evenly spacing points (by distance or time interval) between adjacent points. These gaps sometimes occur in my tracklines when the tracking teams misses one or several surfacings of a whale or because the whale is obscured by a large rock.

After speed filtration and interpolation has occurred, the tracklines are ready to be analyzed using Residence in Space and Time (RST; Torres et al. 2017) to assign behavior state to each location. The questions I am hoping to answer for my thesis are based upon knowing the behavioral state of a whale at a given location and time. In order for me to draw conclusions over whether or not a whale prefers to forage by a reef with kelp rather than a reef without kelp, or whether it prefers Holmesimysis sculpta over Neomysis rayii, I need to know when a whale is actually foraging and when it is not. When we track whales from our cliff site, we assign a behavior to each marked location of an individual. It may sound simple to pick the behavior a whale is currently exhibiting, however it is much harder than it seems. Sometimes the behavioral state of a whale only becomes apparent after tracking it for several minutes. Yet, it’s difficult to change behaviors retroactively while tracking a whale and the qualitative assignment of behavior states is not an objective method. Here is where RST comes in.

Those of you who have been following the blog for a few years may recall a post written in early 2017 by Rachael Orben, a former post-doc in the GEMM Lab who currently leads the Seabird Oceanography Lab. The post discussed the paper “Classification of Animal Movement Behavior through Residence in Space Time” written by Leigh and Rachael with two other collaborators, which had just been published a few days prior. If you want to know the nitty gritty of what RST is and how it works, I suggest reading Rachael’s blog, the GEMM lab’s brief description of the project and/or the actual paper since it is an open-access publication. However, in a nut shell, RST allows a user to identify three primary behavioral states in a tracking dataset based on the time and distance the individual spent within a given radius. The three behavioral categories are as follows:

*Fig 4. Visualization of the three RST behavioral categories. Taken from Torres et al. (2017).*

Transit – characterized by short time and distance spent within an area (radius of given size), meaning the individual is traveling.
Time-intensive – characterized by a long time spent within an area, meaning the individual is spending relatively more time but not moving much distance (such as resting in one spot).
Time & distance-intensive – characterized by relatively high time and distances spent within an area, meaning the individual is staying within and moving around a lot in an area, such as searching or foraging.

What behavior these three categories represent depends on the resolution of the data analyzed. Is one point every day for two years? Then the data are unlikely to represent resting. Or is the data 1 point every second for 1 hour? In which case travel segments may cover short distances. On average, my gray whale tracklines are composed of a point every 4-5 minutes for 1-2 hours. Bases on this scale of tracking data, I will interpret the categories as follows: Transit is still travel, time & distance-intensive points represent locations where the whale was searching because it was moving around one area for a while, and time-intensive points represent foraging behavior because the whale has ‘found what it is looking for’ and is spending lots of time there but not moving around much anymore. The great thing about RST is that it removes the bias that is introduced by my field team when assigning behavioral states to individual whales (Figure 5). RST looks at the tracklines in a very objective way and determines the behavioral categories quantitatively, which helps to remove the human subjectivity.

While it took quite a bit of troubleshooting in R and overcoming error messages to make the codes run on my data, I am proud to have results that are interesting and meaningful with which I can now start to answer some of my many research questions. My next steps are to create interpolated prey density and distance to kelp layers in ArcGIS. I will then be able to overlay my cleaned up tracklines to start teasing out potential patterns and relationships between individual whale foraging movements and their environment.

Literature cited

Torres, L. G., R. A. Orben, I. Tolkova, and D. R. Thompson. 2017. Classification of animal movement behavior through residence in space and time. PLoS ONE: doi. org/10.1371/journal.pone.0168513.

A Series of Short Stories from A Field Season in Port Orford

By Mia Arvizu, Marine Studies Initiative (MSI) & GEMM Lab summer intern, OSU junior

Part 1: The Green Life Jacket

The swells are churning and for once my stomach is calm. I take advantage of it while I can, and head out on the kayak. Another beautiful day, another good data set. After about three hours in the kayak and a long paddle fighting winds and swells, we arrive at TC1. That’s short for Tichenor Cove Station 1. I’m fairly tired by now but my teammate and I are determined to finish all stations today. GPS says we arrived, and I paddle against any slight movement to keep us on station. It’s getting more difficult though, so I check in with Anthony, one of the high school interns this summer. “Anthony, have you sent the GoPro camera down yet?” I take a quick look back peering over my green life jacket. Red flash, and I know it’s on. Anthony sends it down, and I watch as it plunges into depths I couldn’t see on my own. I’m confident it’s doing its job.

Kayaking on the Port Orford coast collecting prey data on the foraging ecology of whales and collecting information on the abundance of sea urchins. Source: A. Howe.

Part 2: The GoPro Dive

The green life jacket is familiar, but there’s a different soul, a different face every year. It’s the same month though. August – the month of whales.

Red flash, I’m on, and it’s my time to shine. The scientists debrief me on my latest mission, and I’m alive. “Secchi depth .75 meters.” Hmm, low visibility. This may be a tough one. “Station TC1” One of my favorites but challenging no doubt. “Time is 10:36. 5, 6, 7, 8…” I’m ready. A flush of swirling water surrounds me as I plunge into the depths of a different realm. I’m cocooned in the beauty of an ocean so blue, so majestic, so entrancing. Oh, the mission! Right, I need to stay focused. They lurk all around but with sand clouding the water, I can barely see. I just need one good visual of the purple spikes and the swaying green leaves, and the mission will be complete. I glance just to the left and oh my!

Sea urchins actively foraging on kelp at station TC1 in Tichenor Cove. Source: GEMM Lab.

A giant purple spike comes too close. I barely caught a glimpse of it. I need a better shot, but I only have so much control especially with these undercurrents. I’m ready now though. I peer through the sediment and nothing, but one quick swivel to the right shows me what I feared and what the green life jackets predicted: The purple spikes have grown too many and reduced the swaying greens down to half chewed, severed, scared dead masses. I thought their hypothesis was right, but I didn’t expect this degree of damage. It’s so frightening I almost look away.

But I don’t. I have a mission. So, I look straight ahead documenting the scene. I haven’t seen it this bad in the past years. I wonder what the green life jackets will do about this. I feel a tug, and I’m reeled in. I guess I’ll find out.

GoPro video taken from tandem research kayak during 2019 gray whale field season in Tichenor Cove, Port Orford. Source: GEMM Lab.

Part 3: The Science, how I see it

After collecting data in the kayak, I go back to the field station ready to do data processing. I grab the GoPro and take a look at the video from TC1. I’m both amazed and terrified for the surrounding habitat from what I see. Sea urchins seem to have been actively foraging on kelp stalks.

Last summer, around this time, a previous intern pointed out that he was witnessing damaged kelp and a notable number of urchins in the GoPro videos. Thus, the GEMM Lab is looking into the relationship between kelp health and sea urchin abundance in Port Orford, which can have significant trophic cascades for the rest of the ecosystem, including whales and their zooplankton prey. The hypothesis is that if sea urchin populations increase in number they may actively forage on kelp, reducing the health of that habitat. Many creatures depend on this habitat including zooplankton which whales feed on. I have looked at videos from past years and the temporal difference in the abundance of urchins is stark. A detailed methodology for the project and our pending results will be featured in a later post, but for now this story is unfolding before our eyes and the GoPro’s lens as well.

Part 4: The Transformation from STEM to STEAM

I hope you enjoyed these short stories. As the writer, it was nice to express the ecological phenomena I’ve learned about in the last few weeks between sea urchins and kelp in this creative and artistic outlet. Especially since I feel science can be rigid at times. It can be easy to lose myself in numbers and large datasets. However, by tying together the arts and STEM (Science, Technology, Engineering, Mathematics), there is more space for well-rounded inquiry and expressive results. STEAM, which is STEM with the Arts included, is not a new movement. Examples of STEAM are preserved in the past and is ongoing in present examples. A great example of how the sciences and arts are merged together is in the songs of Aboriginal Australians. These songs can take hours to recite fully and are full of environmental knowledge such as species types, behavior of animals, and edible plants. The combination of art and STEM is also displayed in the modern age and is shown in Leah Heiss’s work to create jewelry that helps measure cardiac data and also helps diabetics administer their insulin.

This is one of Leah’s feature blends of biotechnology and jewelry. It measures cardiac data and is primarily beneficial for patients at risk of heart attacks. Source: Leah Heiss.

There are many ways in which the two subjects can merge together, making each other stronger and better. As a well-rounded student pursuing Environmental Science and interested dance and writing, I am comforted to know that STEAM can allow me to blend my interests.

Intricacies of Zooplankton Species Identification

By Donovan Burns, Astoria High School Junior, GEMM Lab summer intern

The term zooplankton is used to describe a large number of creatures; the exact definition is any animal that cannot move against a sustained current in the marine environment. There are two main types of plankton: holoplankton and meroplankton. Meroplankton are organisms that are plankton for only part of their life cycle. So this makes most sea creatures plankton, for instance, salmon, sunfish, tuna, and most other fish are meroplankton because they start out their lives as plankton. Holoplankton are plankton that remain plankton for their whole lives, these include mysid shrimp, most marine worms, and most jellyfish.

I have spent a good deal of time this summer looking through a microscope at the zooplankton we have captured during sampling from our research kayak, trying to distinguish and identify different species. Telsons, the tail of the tail, are what we use to identify different types of mysid shrimp, which are a primary gray whale prey item along the Oregon coast and the most predominant type of zooplankton we capture in our sampling. For instance Neomysis is a genus of mysid shrimp and is one of the two most abundant zooplankton species we get. Their telsons end with two spikes that are somewhat longer than the spikes on the side of the telson. This look is distinct from Holmesimysis sculpta, the other of the two most abundant zooplankton species we get, which have four-pronged telsons with varying sizes of spikes along the sides of the telson. Alienacanthomysis macropsis is identified by both their long eye stalks and their rather bland rounded telson.

Holmesimysis sculpta
Neomysis
Alienacanthomysis macropsis

However, creatures that are not mysid shrimp cannot be identified this way. Like gammarids, they look like fleas. We have only found one kind of gammarid here in Port Orford this year, Atylus tridens. There are other types but that is the only type we have found this year. After that, we have Caprellidae, also known as skeleton shrimp. They are long and stalky, and have claws in every spot where they could have claws.

Then there are copepods. Copepods are tiny and have long antennae that string down to the sides of their bodies. We also have been seeing lots of crab larvae. I have also seen a couple of polychaete worms, which are marine worms with many legs and segments. The only reason I was able to identify them as polychaetes is due to my marine biology class at Astoria High School where we identified these worms using microscopes before.

We also have had some trouble identifying somethings. For instance, we have found a few individuals of a type of mysid shrimp with a rake-like tail that we are still trying to identify. Also, we have captured some jellyfish that we are not trying to identify. When the kayak team gets back in from gathering samples, we freeze the samples to kill and preserve the critters in them. This process turns the jellyfish to mush, so they are hard to identify.

Mystery mysid with rake-like tail.

To identify these zooplankton and other critters, we put them into a Petri dish and under a dissection scope, at which point we use forceps to move and pivot creatures. If a jellyfish had just eaten another plankton, we have to cut it open to get the plankton out so we can identify it.

Sometimes we have large samples of thousands of the same creature, in this case, we would normally sub-sample it. Sub-sampling is when we take a portion of a sample and identify and count individual zooplankton in that sub-sample. Then we multiply those counts by the portion of the whole sample to get the approximate total number that are in that sample. For instance, say we had a rather large sample, we would take a tenth of that sample and count what is in it. Say we count 500 individuals in that tenth. We would then multiply 500 by ten to get the total number in that whole sample.

Then there are some plankton that we do not catch, like large jellyfish. The kayak team has gotten photos of a giant jellyfish that was nearly a meter long.

Jellyfish seen by the kayak team. Source: L. Hildebrand.

All in all, Port Orford has an amazing and diverse population of marine life. From gray whales to thresher sharks to mysid shrimp to copepods to jellyfish, this little ecosystem has pretty much some of everything.

Fieldwork experience as a GEMM Lab intern

By Anthony Howe, Astoria High School graduate 2019, GEMM Lab summer intern

Murphy’s Law says that “things will go wrong in any given situation if you give them a chance”. This statement certainly applies to research where you never really know what is going to happen when performing fieldwork. You can only try to be prepared for all of the situations. When I arrived at the Oregon State University (OSU) Field Station in Port Orford, I had no idea that it would harbor some of the best educational experiences I have ever had. I had no idea what a theodolite was, nor did I know how to kayak in the ocean, but I learned fast. When we first started being trained on using a theodolite and the program that processes the data, Pythagoras, we had some problems. The theodolite would not stay level, but just as we were learning how to work the theodolite, we also learned how to work as a team. When we finally managed to level the theodolite, which did take a few days, I began to realize the hard work of doing fieldwork. You can be prepared but there will always be something that goes wrong, and that’s okay. I have learned that mistakes happen and cannot be dwelled on. Only learned from. No one is perfect.

Fig 1. Me holding two zooplankton samples after collecting them on the kayak. Source: L. Hildebrand.

Just two days ago I was on our tandem research kayak with Mia Arvizu, the OSU Marine Studies Initiative (MSI) undergraduate intern. When we go out on the kayak, we paddle around our study area and go to GPS-marked “stations” to collect prey samples of zooplankton, test for water visibility using a Secchi disk, and send a GoPro underwater to have a better understanding of what is going on under the surface. While sampling at Station 15 in Mill Rocks I lowered the GoPro into the water using a downrigger. When the GoPro reached the bottom, I began to pull it up, only to realize it had gotten snagged in a crevice. I gave the line to which the GoPro is attached some slack and began to give Mia instructions to move to different spots to try and retrieve the GoPro out of this tight crevice. Unfortunately, I did not realize all of the lines had wrapped themselves underneath the downrigger and as soon as a swell came up, the line broke. My eyes widened as I realized what had just happened. Thankfully, I managed to grasp the last of the remaining line left connected to the GoPro and pulled it back into the kayak using my hand wrapped in a towel since the line is thin and can cut into your hands easily. Only then did I realize that neither Mia nor I had packed a knife in the event we needed to cut a line. We sat and pondered ideas of how to cut the last of the line so that I could reattach the GoPro to the downrigger. Mia came up with the idea to use a barnacle or a mussel, and it worked perfectly. We were proud of ourselves for being resourceful and using nature to our advantage. But as soon as I finished using the mussel to cut the line, Lisa’s voice came over the VHF radio that we always carry with us in the kayak that there were scissors in the First Aid Kit that is stowed in the dry hatch of the kayak. Mia and I looked at each other and could only laugh. The kayak team can be rough at times but it’s made up by the fact that we get beautiful prey samples and stunning GoPro videos of what is below the water.

Fig 2. Mia and myself paddling the kayak across “The Passage”, the approximately 1 km stretch between Mill Rocks and Tichenor Cove, our two study sites. Red Fish Rocks, which is Oregon’s first Marine Reserve, can be seen in the background. Source: L. Hildebrand.

After all of the kayak sampling is done we organize and store our gear, and then go to the lab. In the lab, one person will clean all tools and devices touched by saltwater while the other sieves all of our zooplankton samples. Each sample is individually sieved and then placed in a sample jar with its station name on it and placed into the freezer. We put them in the freezer to increase the longevity of the samples, as well as euthanizing all zooplankton so that they are easier to identify under a dissection scope. After all of that is done we take a 45-minute break before taking over the cliff team job so they can have a lunch break, as well as a rest from staring at the glare of the water all day searching for whales.

The cliff team generally consists of two people. One person will be on the theodolite, and the other will be on the laptop. The idea is that the theodolite uses the Pythagorean Theorem to get the exact coordinates of the whale we are spotting. This allows us to track exactly where the whales are going, what they are doing, how they’re doing it, and the fashion in which they’re doing it. The fixed points will fall on a plotted map on the laptop. The other job of the person on the laptop is to take pictures when possible so we can identify the whales. For instance, there is a whale named Buttons that has been recorded during past summers in Port Orford. By using the photos we take of a whale, combined with previous data about the whale named Buttons, we can cross-reference the body color and patterns of the whale to be able to re-identify Buttons. We now know that we have seen Buttons for 4 consecutive days feeding in our study area. The camera also acts as a tool to take pictures of whales not just for identity but for rare activity. Today while on the cliff Mia and I spotted a whale in Tichenor Cove (one of our sampling sites) that breached four times! These experiences are rare and beautiful. You never think about how big a whale truly is until you see it almost completely leap out of the water – it is beautiful.

Fig 3. The post-breach splash created by *Buttons*. Unfortunately we weren’t able to get a good photo from the cliff because we were too stunned by the fact that we were seeing this rare behavior. Source: GEMM Lab.

I’m sure more mistakes will be made but that’s okay. I have many more experiences to witness, and many more memories to make from this internship, as well as challenges. I couldn’t be more than happy with the team I have to share all of these learning experiences and hardships with.

Introducing Crew Cinco – the Port Orford Gray Whale Foraging Ecology Field Team of 2019

By Lisa Hildebrand, MSc student, OSU Department of Fisheries and Wildlife, Geospatial Ecology of Marine Megafauna Lab

It seems unfathomable to me that one year and two months ago I had never used a theodolite before, never been in an ocean kayak before, never identified zooplankton before, never seen a Time-Depth-Recorder (TDR) before. Now, one year later, it seems like all of those tools, techniques and things are just a couple of old friends with which I am being reunited with again. My second field season as the project team lead of the gray whale foraging ecology project in Port Orford (PO) is slowly getting underway and so many of the lessons I learned from my first field season last year have already helped me tremendously this year. I know how to interpret weather forecasts and determine whether it will be a kayak-appropriate day. I know how to figure out the quirks of Pythagoras, the program we use to interface with our theodolite which helps us track whales from our cliff site. I know how to keep track of a budget and feed a team of hungry researchers after a long day of work. Knowing all of these things ahead of this year’s field season have made me feel a little more prepared and at ease with the training of my team and the work to be done. Nevertheless, there are always new curveballs to be thrown my way and while they can often be frustrating, I enjoy the challenges that being a team leader has to offer as it allows me to continue to grow as a field research scientist.

Figure 1. Crew Cinco tracks a whale in Tichenor Cove. Source: L Hildebrand.

2019 marks the fifth year that this project has been taking place in PO. Back in the summer of 2015, former GEMM Lab Master’s student Florence Sullivan started this project together with Leigh. That year the research focused more on investigating vessel disturbance to gray whales by comparing sites of heavy (Boiler Bay) to low boat traffic (Port Orford). The effort found that there were significant differences in gray whale activity budgets between the heavy and low boat traffic conditions (Sullivan & Torres 2018). The following year, the focus of the research switched to being more on the foraging ecology side of things and the project was based solely out of Port Orford, as it continues to be to this day. Being in our fifth year means that we are starting to build a humbly-sized database of sightings across multiple years allowing me to investigate potential individual specialization of the whales that we document. Similarly, multiple years of prey sampling is starting to reveal temporal and spatial trends of prey community assemblages.

Figure 2. Buttons (pictured above) is one of the stars of the Port Orford gray whale foraging ecology project as he has been seen every year since 2016. Crew Cinco has already seen him three times since the start of August. Source: L Hildebrand.

It has become a tradition to come up with a name for the field team that spends 6 weeks at the Oregon State University (OSU) Port Orford Field Station to collect the data for the project. It started with Team Ro“buff”stus in 2015, which I believe carried through until 2017. This is understandable since it’s such a clever name. It’s a play on the species name for gray whales, robustus, but the word “Buff” has been substituted in the center. Buffs are pieces of cloth sewn into a cylindrical shape, often with fun patterns or colors, that can be used as face masks, headbands, and scarves, which come in very handy when your face is exposed to the elements. Doing this project, we can be confronted by wind, sun, fog and sea water all in one day, so Buffs have definitely served the team members very well over the years. Last year, as the project’s torch was passed from Florence to myself, I felt a new team name was apt, and so last year’s team decided our name would be Team Whale Storm. I believe it was because we said we would take the whale world by storm with our insanely good theodolite tracking and kayak sampling skills. With a new year and new team upon us, a new team name was in order. As the title of this blog post indicates, this year the team is called Crew Cinco. The reason behind this name is that we are the fifth team to carry out this field work. Since the gray whales breed in the lagoons of Baja California, Mexico, I like to think that their native language is Spanish. Hence, we have decided that instead of being Crew Five, we are Crew Cinco, as cinco is the Spanish word for five (besides, alliteration makes for a much better team name).

Now that you are up to speed on the history of the PO gray whale project, let me tell you a little about who is part of Crew Cinco and what we have been up to already.

This year’s Marine Studies Initiative OSU undergraduate intern is Mia Arvizu. Mia has just finished her sophomore year at OSU and majors in Environmental Science. Besides being my co-captain this year in the field, Mia is also undertaking an independent research project which focuses on the relationship between sea urchin abundance, kelp health and gray whale foraging. She will tell you all about this project in a few weeks when she takes over the GEMM lab blog. Aside from her interest in ecology and the way science can be used to help local communities in a changing environment, Mia is a dancer, having performed in several dances in OSU’s annual luau this year, and she is currently teaching herself Spanish and Hawaiian.

Both of our high school interns this year are from Astoria. Anthony Howe has just graduated from Astoria High School and will be starting at Clatsop Community College in the fall. His plan is to transfer to OSU and to pursue his interest in marine biology. Anthony, like myself, was born in Germany and lived there until he was six, which means that he is able to speak fluent German. He also introduced the team to the wonders of the Instant Pot, which has made cooking for a team of four hungry scientists much simpler.

Donovan Burns is our other high school intern. He will be going into his junior year in the fall. Donovan never ceases to amaze us with the seemingly endless amounts of general knowledge he has, often sharing facts about Astoria’s history to Asimov’s Laws of Robotics to pickling vegetables, specifically carrots, with us during dinner or while scanning for whales on the cliff site. He also named the first whale we saw here this season – Speckles.

Figure 3. Crew Cinco, from left to right: Anthony Howe, Donovan Burns, Lisa Hildebrand and Mia Arvizu. Source: L Torres.

Crew Cinco has already been in PO for two weeks now. After having a full team meeting with Leigh in Newport and a GEMM lab summer pizza party, we headed south to begin our 6-week field season. It’s hard to believe that the two training weeks are already over. The team worked hard to figure out the subtleties of the theodolite, observe different gray whales and start to understand their dive and foraging patterns, undertake a kayak paddle & safety course, as well as CPR and First Aid training, learn about data processing and management, and how to use a variety of gizmos to aid us in data collection. But it hasn’t all been work. We enjoyed a day in the Californian Redwoods on one of our day’s off and picked blueberries at the Twin Creek Ranch, stocking our freezer with several bags of juicy berries. We have played ‘Sorry!’ perhaps one too many times already (we are in desperate need of some more boardgames if anyone wants to send some our way to the field station!), and enjoyed many walks and runs on beautiful Battle Rock Beach.

Crew Cinco in awe of the Redwoods
Crew Cinco’s blueberry harvest
Crew Cinco after their kayak paddle & safety course South Coast Tours

The next four weeks will not be easy – very early mornings, lots of paddling and squinting into the sun, followed by several hours in the lab processing samples and backing up data. But the next four weeks will also be extremely rewarding – learning lots of new skills that will be valuable beyond this 6-week period, revealing ecological trends and relationships, and ultimately (the true reason for why Mia, Anthony, Donovan and myself are more than happy to put in 6 weeks-worth of hard work), the chance to see whales every day up close and personal. Follow Crew Cinco’s journey over the next few weeks as my interns will be posting to the blog for the next three weeks!

References

Sullivan, F.A., & Torres L.G. Assessment of vessel disturbance to gray whales to inform sustainable ecotourism. Journal of Wildlife Management, 2018. 82: 896-905.

Lingering questions on the potential to bring sea otters back to Oregon

By Dominique Kone, Masters Student in Marine Resource Management

By now, I’m sure you’re aware of recent interests to reintroduce sea otters to Oregon. To inform this effort, my research focuses on predicting suitable sea otter habitat and investigating the potential ecological effects if sea otters are reintroduced in the future. This information will help managers gain a better understanding of the potential for sea otters to reestablish in Oregon, as well as how Oregon’s ecosystems may change via top-down processes. These analyses will address some sources of uncertainties of this effort, but there are still many more questions researchers could address to further guide this process. Here, I note some lingering questions I’ve come across in the course of conducting my research. This is not a complete list of all questions that could or should be investigated, but they represent some of the most interesting questions I have and others have in Oregon.

The questions, and our associated knowledge on each of these topics:

Is there enough available prey to support a robust sea otter population in Oregon?

Sea otters require approximately 30% of their own body weight in food every day (Costa 1978, Reidman & Estes 1990). With a large appetite, they not only need to spend most of their time foraging, but require a steady supply of prey to survive. For predators, we assume the presence of suitable habitat is a reliable proxy for prey availability (Redfern et al. 2006). Whereby, quality habitat should supply enough prey to sustain predators at higher trophic levels.

In making these habitat predictions for sea otters, we must also recognize the potential limitations of this “habitat equals prey” paradigm, in that there may be parcels of habitat where prey is unavailable or inaccessible. In Oregon, there could be unknown processes unique to our nearshore ecosystems that would support less prey for sea otters. This possibility highlights the importance of not only understanding how much suitable habitat is available for foraging sea otters, but also how much prey is available in these habitats to sustain a viable otter population in the future. Supplementing these habitat predictions with fishery-independent prey surveys is one way to address this question.

Credit: Suzi Eszterhas via Smithsonian Magazine

How will Oregon’s oceanographic seasonality alter or impact habitat suitability?

Sea otters along the California coast exist in an environment with persistent Giant kelp beds, moderate to low wave intensity, and year-round upwelling regimes. These environmental variables and habitat factors create productive ecosystems that provide quality sea otter habitat and a steady supply of prey; thus, supporting high densities of sea otters. This environment contrasts with the Oregon coast, which is characterized by seasonal changes in bull kelp and wave intensity. Summer months have dense kelp beds, calm surf, and strong upwellings. While winter months have little to no kelp, weak upwellings, and intense wave climates. These seasonal variations raise the question as to how these temporal fluctuations in available habitat could impact the number of sea otters able to survive in Oregon.

In Washington – an environment like Oregon – sea otters exhibit seasonal distribution patterns in response to intensifying wave climates. During calm summer months, sea otters primarily forage along the outer coast, but move into more protected areas, such as the Strait of Juan de Fuca, during winter months (Laidre et al. 2009). If sea otters were reintroduced to Oregon, we may very well observe similar seasonal movement patterns (e.g. dispersal into estuaries), but the degree to which this seasonal redistribution and reduction in foraging habitat could impact sea otter reestablishment and recovery is currently unknown.

In the event of a reintroduction, do northern or southern sea otters have a greater capacity to adapt to Oregon environments?

In the early 1970’s, Oregon’s first sea otter translocation effort failed (Jameson et al. 1982). Since then, hypotheses on the potential ecological differences between northern and southern sea otters have been proposed as potential factors of the failed effort, potentially due to different abilities to exploit specific prey species. Studies have demonstrated that northern and southern sea otters have slight morphological differences – northern otters having larger skulls and teeth than southern otters (Wilson et al. 1991). This finding has created the hypothesis that the northern otter’s larger skull and teeth allow it to consume prey with denser exoskeletons, and thereby can exploit a greater diversity of prey species. However, there appears to be a lack of evidence to suggest larger skulls and teeth translate to greater bite force. Based on morphology alone, either sub-species could be just as successful in exploiting different prey species.

A different direction to address questions around adaptability is to look at similarities in habitat and oceanographic characteristics. Sea otters exist along a gradient of habitat types (e.g. kelp forests, estuaries, soft-sediment environments) and oceanographic conditions (e.g. warm-temperature to cooler sub-Arctic waters) (Laidre et al. 2009, Lafferty et al. 2014). Yet, we currently don’t know how well or quickly otters can adapt when they expand into new habitats that differ from ones they are familiar with. Sea otters must be efficient foragers and need to acquire skills that allow them to effectively hunt specific prey species (Estes et al. 2003). Hypothetically, if we take sea otters from rocky environments where they’ve developed foraging skills to hunt sea urchins and abalones, and place them in a soft-sediment environment, how quickly would they develop new foraging skills to exploit soft-sediment prey species? Would they adapt quickly enough to meet their daily prey requirements?

Credit: Eric Risberg/Associated Press via The Columbian

In Oregon, specifically, how might climate change impact sea otters, and how might sea otters mediate climate impacts?

Climate change has been shown to directly impact many species via changes in temperature (Chen et al. 2011). Some species have specific thermal tolerances, in which they can only survive within a specified temperature range (i.e. maximum and minimum). Once the temperature moves out of that range, the species can either move with those shifting water masses, behaviorally adapt or perish (Sunday et al. 2012). It’s unclear if and how changing temperatures will impact sea otters, directly. However, sea otters could still be indirectly affected via impacts to their prey. If prey species in sea otter habitat decline due to changing temperatures, this would reduce available food for otters. Ocean acidification (OA) is another climate-induced process that could indirectly impact sea otters. By creating chemical conditions that make it difficult for species to form shells, OA could decrease the availability of some prey species, as well (Gaylord et al. 2011).

Interestingly, these pathways between sea otters and climate change become more complex when we consider the potentially mediating effects from sea otters. Aquatic plants – such as kelp and seagrass – can reduce the impacts of climate change by absorbing and taking carbon out of the water column (Krause-Jensen & Duarte 2016). This carbon sequestration can then decrease acidic conditions from OA and mediate the negative impacts to shell-forming species. When sea otters catalyze a tropic cascade, in which herbivores are reduced and aquatic plants are restored, they could increase rates of carbon sequestration. While sea otters could be an effective tool against climate impacts, it’s not clear how this predator and catalyst will balance each other out. We first need to investigate the potential magnitude – both temporal and spatial – of these two processes to make any predictions about how sea otters and climate change might interact here in Oregon.

In Summary

There are several questions I’ve noted here that warrant further investigation and could be a focus for future research as this potential sea otter reintroduction effort progresses. These are by no means every question that should be addressed, but they do represent topics or themes I have come across several times in my own research or in conversations with other researchers and managers. I think it’s also important to recognize that these questions predominantly relate to the natural sciences and reflect my interest as an ecologist. The number of relevant questions that would inform this effort could grow infinitely large if we expand our disciplines to the social sciences, economics, genetics, so on and so forth. Lastly, these questions highlight the important point that there is still a lot we currently don’t know about (1) the ecology and natural behavior of sea otters, and (2) what a future with sea otters in Oregon might look like. As with any new idea, there will always be more questions than concrete answers, but we – here in the GEMM Lab – are working hard to address the most crucial ones first and provide reliable answers and information wherever we can.

References:

Chen, I., Hill, J. K., Ohlemuller, R., Roy, D. B., and C. D. Thomas. 2011. Rapid range shifts of species associated with high levels of climate warming. Science. 333: 1024-1026.

Costa, D. P. 1978. The ecological energetics, water, and electrolyte balance of the California sea otter (Enhydra lutris). Ph.D. dissertation, University of California, Santa Cruz.

Estes, J. A., Riedman, M. L., Staedler, M. M., Tinker, M. T., and B. E. Lyon. 2003. Individual variation in prey selection by sea otters: patterns, causes and implications. Journal of Animal Ecology. 72: 144-155.

Gaylord et al. 2011. Functional impacts of ocean acidification in an ecologically critical foundation species. Journal of Experimental Biology. 214: 2586-2594.

Jameson, R. J., Kenyon, K. W., Johnson, A. M., and H. M. Wight. 1982. History and status of translocated sea otter populations in North America. Wildlife Society Bulletin. 10(2): 100-107.

Krause-Jensen, D., and C. M. Duarte. 2016. Substantial role of macroalgae in marine carbon sequestration. Nature Geoscience. 9: 737-742.

Lafferty, K. D., and M. T. Tinker. 2014. Sea otters are recolonizing southern California in fits and starts. Ecosphere.5(5).

Laidre, K. L., Jameson, R. J., Gurarie, E., Jeffries, S. J., and H. Allen. 2009. Spatial habitat use patterns of sea otters in coastal Washington. Journal of Marine Mammalogy. 90(4): 906-917.

Redfern et al. 2006. Techniques for cetacean-habitat modeling. Marine Ecology Progress Series. 310: 271-295.

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Eyes from Space: Using Remote Sensing as a Tool to Study the Ecology of Blue Whales

By Christina Garvey, University of Maryland, GEMM Lab REU Intern

It is July 8^th and it is my 4^th week here in Hatfield as an REU intern for Dr. Leigh Torres. My name is Christina Garvey and this summer I am studying the spatial ecology of blue whales in the South Taranaki Bight, New Zealand. Coming from the east coast, Oregon has given me an experience of a lifetime – the rugged shorelines continue to take my breath away and watching sea lions in Yaquina Bay never gets old. However, working on my first research project has by far been the greatest opportunity and I have learned so much in so little time. When Dr. Torres asked me to contribute to this blog I was unsure of how I would write about my work thus far but I am excited to have the opportunity to share the knowledge I have gained with whoever reads this blog post.

The research project that I will be conducting this summer will use remotely sensed environmental data (information collected from satellites) to predict blue whale distribution in the South Taranaki Bight (STB), New Zealand. Those that have read previous blogs about this research may remember that the STB study area is created by a large indentation or “bight” on the southern end of the Northern Island. Based on multiple lines of evidence, Dr. Leigh Torres hypothesized the presence of an unrecognized blue whale foraging ground in the STB (Torres 2013). Dr. Torres and her team have since proved that blue whales frequent this region year-round; however, the STB is also very industrial making this space-use overlap a conservation concern (Barlow et al. 2018). The increasing presence of marine industrial activity in the STB is expected to put more pressure on blue whales in this region, whom are already vulnerable from the effects of past commercial whaling (Barlow et al. 2018) If you want to read more about blue whales in the STB check out previous blog posts that talk all about it!

Figure 1. A blue whale surfaces in front of a floating production storage and offloading vessel servicing the oil rigs in the South Taranaki Bight. Photo by D. Barlow.

Figure 2. South Taranaki Bight, New Zealand, our study site outlined by the red box. Kahurangi Point (black star) is the site of wind-driven upwelling system.

The possibility of the STB as an important foraging ground for a resident population of blue whales poses management concerns as New Zealand will have to balance industrial growth with the protection and conservation of a critically endangered species. As a result of strong public support, there are political plans to implement a marine protected area (MPA) in the STB for the blue whales. The purpose of our research is to provide scientific knowledge and recommendations that will assist the New Zealand government in the creation of an effective MPA.

In order to create an MPA that would help conserve the blue whale population in the STB, we need to gather a deeper understanding of the relationship between blue whales and this marine environment. One way to gain knowledge of the oceanographic and ecological processes of the ocean is through remote sensing by satellites, which provides accessible and easy to use environmental data. In our study we propose remote sensing as a tool that can be used by managers for the design of MPAs (through spatial and temporal boundaries). Satellite imagery can provide information on sea surface temperature (SST), SST anomaly, as well as net primary productivity (NPP) – which are all measurements that can help describe oceanographic upwelling, a phenomena that is believed to be correlated to the presence of blue whales in the STB region.

Figure 3. The stars of the show: blue whales. A photograph captured from the small boat of one animal fluking up to dive down as another whale surfaces close by. (Photo credit: L. Torres)

Past studies in the STB showed evidence of a large upwelling event that occurs off the coast of Kahurangi Point (Fig. 2), on the northwest tip of the South Island (Shirtcliffe et al. 1990). In order to study the relationship of this upwelling to the distribution of blue whales, I plan to extract remotely sensed data (SST, SST anomaly, & NPP) off the coast of Kahurangi and compare it to data gathered from a centrally located site within the STB, which is close to oil rigs and so is of management interest. I will first study how decreases in sea surface temperature at the site of upwelling (Kahurangi) are related to changes in sea surface temperature at this central site in the STB, while accounting for any time differences between each occurrence. I expect that this relationship will be influenced by the wind patterns, and that there will be changes based on the season. I also predict that drops in temperature will be strongly related to increases in primary productivity, since upwelling brings nutrients important for photosynthesis up to the surface. These dips in SST are also expected to be correlated to blue whale occurrence within the bight, since blue whale prey (krill) eat the phytoplankton produced by the productivity.

Figure 4. A blue whale lunges on an aggregation of krill. UAS piloted by Todd Chandler.

To test the relationships I determine between remotely sensed data at different locations in the STB, I plan to use blue whale observations from marine mammal observers during a seismic survey conducted in 2013, as well as sightings recorded from the 2014, 2016, and 2017 field studies led by Dr. Leigh Torres. By studying the statistical relationships between all of these variables I hope to prove that remote sensing can be used as a tool to study and understand blue whale distribution.

I am very excited about this research, especially because the end goal of creating an MPA really gives me purpose. I feel very lucky to be part of a project that could make a positive impact on the world, if only in just a little corner of New Zealand. In the mean time I’ll be here in Hatfield doing the best I can to help make that happen.

References:

Barlow DR, Torres LG, Hodge KB, Steel D, Baker CS, Chandler TE, Bott N, Constantine R, Double MC, Gill P, Glasgow D, Hamner RM, Lilley C, Ogle M, Olson PA, Peters C, Stockin KA, Tessaglia-hymes CT, Klinck H (2018) Documentation of a New Zealand blue whale population based on multiple lines of evidence. Endanger Species Res 36:27–40.

Shirtcliffe TGL, Moore MI, Cole AG, Viner AB, Baldwin R, Chapman B (1990) Dynamics of the Cape Farewell upwelling plume, New Zealand. New Zeal J Mar Freshw Res 24:555–568.

Torres LG (2013) Evidence for an unrecognised blue whale foraging ground in New Zealand. New Zeal J Mar Freshw Res 47:235–248.

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