Current Projects Archives - Page 3 of 7 - Geospatial Ecology of Marine Megafauna Laboratory

[B]reaching New Discoveries about Gray Whales in Oregon

By Haley Kent, Marine Studies Initiative (MSI) & summer GEMM Lab intern, OSU senior

“BLOW!”, yells a team “Whale Storm” member, as mist remains above the water from an exhaling gray whale (Eschrichtius robustus). While based at the Port Orford Field Station for 6 weeks of my final summer as an undergrad at Oregon State University my heart has only grown fonder for marine wildlife. I am still in awe of this amazing opportunity of researching the foraging ecology of gray whales as a Marine Studies Initiative and GEMM Lab intern. From this field work I have already learned so much about gray whales and their zooplankton prey, and now it’s time to analyze the data we have collected and see what ecological stories we can uncover.

Figure 1. Robyn and Haley enjoy their time in the research kayak. Photo by Lisa Hildebrand.

WORK IN THE FIELD

This internship is my first field work experience and I have learned many skills and demands needed to study marine wildlife: waking up before the sun (every day begins with screaming alarms), being engulfed by nature (Port Orford is a jaw-dropping location with rich biodiversity), packing up damp gear and equipment to only get my feet wet in the morning ocean waves again, and of course waiting on the weather to cooperate (fog, wind, swell). I wouldn’t want it any other way.

Figure 2. Smokey sunrise from the research kayak. Photo by Haley Kent.

Whether it is standing above the ocean on the ‘Cliff Site’ or sitting in our two-man kayak, every day of this internship has been full of new learning experiences. Using various field work techniques, such as using a theodolite (surveying equipment to track whale location and behavior), Secchi disks (to measure water clarity), GoPro data collection, taking photos of wildlife, and many more tools, have given me a new bank of valuable skills that will stick with me into my future career.

Figure 3. Haley drops Secchi disk from the research kayak. Photo by Dylan Gregory.

Data Analysis

To maximize my amazing internship experience, I am conducting a small data analysis project using the data we have collected these past weeks and in previous summers. There are so many questions that can be asked of these data, but I am particularly interested in how many times individual gray whales return to our study area to forage seasonally or annually, and if these individual whales forage preferentially where certain zooplankton prey are available.

Photo Identification

After many hours of data collection in the field either in the kayak or on the cliff, we get to take a breather in the lab to work on various projects we are each assigned. Some job tasks include processing data, identifying zooplankton, and looking through the photos taken that day to potentially identify a known whale. Once photos are processed and saved onto the rugged laptop, they are ready for some serious one on one. Looking through each of the 300 photos captured each day can be very tedious, but it is worthwhile when a match is found. Within the photos of each individual whale I first determine whether it is the left or right side of the whale – if we are lucky we get both! – and maybe even a fluke (tail) photo!

Figure 4. Buttons’ left side. Photo taken by Gray Whale Team of 2018.

Figure 5. Buttons’ left side. Photo taken by Gray Whale Team of 2017.

The angles of these photos (Fig. 4 & 5) are very different, so it could be difficult to tell these are the same whale. But, have a closer look at the pigmentation patterns on this whale. Focus on a single spot or area of spots, and see how patterns line up. Does that match in the same area in the next photo? If yes, you could have yourself a match!

Buttons, one of the identified gray whales (Fig. 4 & 5), was seen in 2016, 17, and 18. I was so excited to identify Buttons for the 3^rdyear in a row as this result demonstrates this whale’s preference for foraging in Port Orford.

Zooplankton and whale foraging behavior

By using the theodolite we track the whale’s position from the cliff location. I have plugged these coordinates into Google Earth, and compared the coordinates to our zooplankton sample stations from that same day. These methods allow me to assess where the whale spent time, and where it did not, which I can then relate to the zooplankton species and abundance we caught in our sample tows (we use a net from the research kayak to collect samples throughout the water column).

Figure 6. *Holmesimysis sculpta*. This species can range between 4-12mm. The size of this zooplankton relative to the large gray whales foraging on it shows the whale’s incredible senses for prey preference. Photo source: Scripps Institute of Oceanography.

Results (preliminary)

‘Eyeball’ is one of our resident whales that we have identified regularly throughout this season here in Port Orford. I have compared the amount of time Eyeball has spent near zooplankton stations to the prey community we captured at each station.

There is a positive trend in the amount of time the whale spent in an area with the percent abundance of Holmesimysis sculpta (Fig. 7: blue trend line).

Figure 7. Comparative plot between the amount of time the whale “Eyeball” spent within 50m of each zooplankton sampling station and the relative amount of zooplankton species caught at each station. Note the positive trend between time and *Holmesimysis sculpta*, and the negative trend relative to *Neomysis* sp. or Caprellidae.

Conversely, there is an inverse trend with two other zooplankton species: Neomysis sp. (grey trend line) and Caprellidae (orange trend line). These results suggest that Eyeball has a foraging preference for areas where Holmesimysis sculpta (Fig. 6) is more abundant. Who would have known a whale could be so picky? Once the season comes to an end, I plan to use more of our data to continue to make discoveries about the foraging preferences of gray whales in Oregon.

Where the Wild Things Are

By Dylan Gregory, GEMM Lab summer 2018 intern, OSU undergraduate transfer

In ecology, biodiversity is a term often touted for its key importance in stable ecosystems. Every organism plays its role in the constant struggle of nature, competing and cooperating with each other for survival. The sun provides the initial energy to primary producers, herbivores eat those producers, and predators then eat the consumers. The food chain is a simplistic way to look at how ecosystems work, and of course, it is more like an intricate web of interactions. Fungus and plants work together to trade nutrients and create a vast network of fertile soils; kelp forests provide habitats and food for a variety of prey that marine predators feed on. There are checks and balances between all these organisms that give breath into the beauty and color we see in ecosystems around the world. And, here in Port Orford is no exception. Coming to the project I expected to see some whales, of course. However only three weeks in and I’ve been absolutely astounded with the amount of marine biodiversity we’ve experienced. These past three weeks have been nothing if, well, wild.

Eschrichtius robustus, The Gray Whale

There was no doubt we would see gray whales, that is what we are here for after all, and studying them in the field has been an incredibly enlightening experience. Watching an animal every day for weeks really gets you into their head. You start to connect with them and think about their behaviors in different ways. You begin to realize that the individuals have unique quirks, habits and tendencies. For example, one whale would feed quickly for a time, and then seem to run out of energy and “log” itself, floating on the surface, taking multiple breaths in succession to recover before diving back down. Many whales come from the south, to feed in Mill Rocks before moving to Tichenor Cove, and then leave our study region through “Hell’s Gate” to the North, often resting a moment, taking multiple breaths and then launching into the open sea. Still, when you think you know these whales, they surprise you with an alarming unpredictability, making tracking them a new experience every day.

Figure 1 A gray whale surprised us by surfacing right next to our kayak during a routine zooplankton sampling. The site has shown to have a significant amount of zooplankton and it must have been very interested in the prey available, completely ignoring our presence. Photo by Haley Kent.

The whale in Fig. 1 surprised us, and honestly, being so close to it was as humbling as it was awesome. I expected to see whales, but never expected such a close encounter. These gentle giants are one of our not so distant relatives in the ocean. Many of us do this kind of research for more than just the science and the data. Many of us do it for the connection we feel to our mammal family.

Phoca vitulina richardii, The Pacific Harbor Seal

I absolutely adore these harbor seals! They’re well known for their friendliness towards humans as their dopey little heads pop up out of the water to greet you with a curious look in their eyes. They like to bob in the surf and stare at us while we’re out sampling in the kayak. At first, we got quite excited seeing one, often startling them as we’d squeal “seal!” to each other and they’d dip back under and scurry away. Now though, they seem more comfortable being around our kayak (Fig. 2).

Figure 2 This harbor seal surfaced next to Haley and me shortly before the whale in Fig 1. We named him Courage, as he stuck around and kept us company during the whole encounter. Photo by Haley Kent.

One day a seal followed Lisa and Hayleigh around the jetty on their way back from sampling, swimming around the kayak and investigating them. Out in Mill Rocks, we often see them stretching on top of the rocks, seemingly doing a little yoga session while basking in the morning sun. Despite their cute and cuddly appearance, they are still predators. With plenty of fish to eat and make them happy, these harbor seals are quite plentiful themselves, and I’d like to think we’ve become quite good friends with the little guys.

Tursiops truncatus, The Bottlenose Dolphin

Figure 3 A shot of the dorsal fin seen on August 9th in Mill Rocks. Photo by Dylan Gregory.

One morning we were in Mill Rocks and a large cloud of fog moved in, so we decided to wait it out before making our passage to Tichenor Cove. While sitting there, enjoying a snack, we noticed some dorsal fins popping up about 100 meters from us. Caught by surprise, Haley and I scrambled for our cameras and lo and behold, we noticed they were a small pod of dolphins! Two adults and a calf. Unfortunately, as you can see from our pictures, it is difficult to identify what species they were exactly.

Figure 4 The head and rostrum of the dolphin seen in Mill Rocks on August 9th. Photo by Dylan Gregory.

After communicating with Lisa and Leigh, we have decided that their dorsal fins were far too big and curved to be harbor porpoises (Fig. 3), and the intersection of the head and rostrum seem to have the classic look of a bottlenose dolphin (Fig. 4).

If these were in fact bottlenose dolphins, why are they here in Port Orford, Oregon? It’s uncommon for them to be so far north in our colder waters. Were they foraging for food? Finding refuge from predators? Is it because our waters are becoming warmer? A sighting like this gives more weight to how climate change is affecting our oceans and how marine animals are responding by adapting their migratory and feeding behaviors.

Pisaster and Pycnopodia, The Common Sea Star and the Sunflower Star

Figure 5 Pisaster sea stars and anemones on a rock in Mill Rocks. No Pycnopodia (often called sunflower stars for their many legs) have been spotted in our study zone. Photo by Haley Kent.

One of the coolest aspects of living at the Port Orford Field Station is the fact that we have access to a lot of engagement with other scientists. For instance, we were able to attend a webinar about Sea Star Wasting Disease (SSWD) research currently happening at OSU by Post Doc Sarah Gravem. In a nutshell, a bacterial disease has been infecting sea stars along the west coast, causing a rapid plummet in their populations. Pisaster and Pycnopodia (Fig. 5) have been particularly affected. They are keystone predators, and as such, hold an important role in intertidal ecosystems. Feeding on snails, urchins, other sea stars and various mollusks, these sea stars maintain species populations and allow for a diverse and stable intertidal zone, which then supports many other near shore marine species. While SSWD’s cause is relatively unknown, Pisaster seems to be recovering while Pycnopodia is still struggling. I’ve even heard some anecdotal reports that fishermen here in Port Orford have noticed the lack of Pycnopodia as well, but they are rather pleased that these “ragmops” have stopped mucking up their lines and crab pots.

Below the Surface

There is a charm to the deep, a mystery and wonder that has captured the imagination of humans ad nauseam. Stories, movies, music and masterpieces of art have been inspired by The Abyss. Below the surface lies a diverse world teeming with life, full of questions and answers to be found. While marine mammals are why we’re here, there’s an entirely different environment under the water that is unseen from the safety of our dry, oxygen rich air. Our research doesn’t involve any diving, and so our eyes under the water are a GoPro camera attached to a downrigger on our kayak. Although designed to measure zooplankton community density, we’ve seen quite a bit more than itty bitty sea bugs in the depths of our little harbor here in Port Orford.

Strongylocentrotus purpuratus, The Purple Sea Urchin

Urchins are known for their bright colors and spiny ball like exterior. Close relatives to the sea stars, urchins inhabit the intertidal zones and also take residence within kelp beds. During our kayak training, we passed by some rocks near the cliffs and it was an awesome sight seeing the diversity of intertidal critters such as anemones, sea stars and sea urchins. However, a week into data collection, we have noticed something startling: a large quantity of the urchins cover the seafloor and the kelp, or at least what was left of the kelp (Fig. 6).

Figure 6 Sea Urchins decimating a kelp bed in Tichenor Cove. Photo captured from GoPro footage.

Sea urchins are important members in their communities. They graze on algae and control it from overwhelming the waters, but when left unchecked urchins can completely decimate kelp beds. This pattern is often referred to as “urchin barrens”. Sea otters and sea stars are the urchin’s main predator, and due to the absence of otters and the emergence of SSWD, the occurrence of urchin barrens has risen. An assessment of the reintroduction of the sea otters to Oregon by Dominique Kone, a GEMM Lab graduate student, is underway, and there is a lot of new research on SSWD, both of which could support the ‘ecosystem control’ of urchin populations. We’ve already spotted the urchins wreaking their havoc on the kelp in two separate sites in Tichenor Cove. Since gray whales primarily feed within these kelp beds, this increase in urchin populations is something that we are monitoring. An urchin barren can happen quickly and causes significant ecosystem damage, so this is not something to ignore. If we lose the kelp, it’s easy to imagine that we may lose the whales.

Alopias vulpinus, The Thresher Shark

Figure 7 A thresher shark spotted in Tichenor Cove in Port Orford, OR. Photo captured by GoPro footage.

By far, the most exciting thing I’ve seen so far has been this lovely creature (Fig. 7). The thresher shark usually inhabits the oceanic and coastal zones in tropical and temperate waters. They feed on pelagic schooling fish, squid and sometimes even shorebirds. They attack by whipping their tails (which grow to be the size of their body!) at their prey to stun them. Threshers are on the IUCN Red List of Threatened Species as “Vulnerable” due to their declining populations. They are often hunted for shark fin soup, or by trophy hunters due to their elegant and unique tails.

Haley, our resident shark enthusiast, was able to tell that this shark was a female by the lack of claspers (male appendages) on her pelvic fin. Why was she here though? During the summer, threshers will migrate to colder yet productive northern waters to feed, and on some rare occasions, such as this one, they will come closer to shore. Perhaps she was chasing prey into the harbor and found it to be full of yummy food, or she is a juvenile, which often stay near the continental shelf.

Either way, we were all surprised and excited to see such an exotic and beautiful species of shark caught on camera in our study zone. She even does a little strut in front of the GoPro camera, showing off her beautiful caudal fin!

Protecting our Wilds

These are only a few examples of the many different animals at work in Port Orford’s ecosystem. Perhaps the biodiversity here is why this is such a hot spot for our whale friends. The productive and lively waters have shown us so many critters, and likely many more we have yet to see. But alas, we have three more weeks of data collection and new discoveries, and I couldn’t be more excited.

“It is a curious situation that the sea, from which life first arose should now be threatened by the activities of one form of that life. But the sea, though changed in a sinister way, will continue to exist; the threat is rather to life itself.”

– Rachel Carson, The Sea Around Us

This experience only drives me further into my pursuit of ecological research. I believe it’s incredibly important to understand the world and how it functions, and to do so before it’s too late. All too often we have breakthrough discoveries in science because something has already fallen apart. Ecosystems are fragile, and climate change, pollution, and other anthropogenic disturbances all have an impact which damage and alter ecosystems and the services they provide. However, it’s an impact we can control with a fundamental understanding of how nature works. With a little hope, some integrity, and a whole lot of passion, I believe we have the power to truly make a difference.

Cold Fingers and Carabiners

By Hayleigh Middleton, GEMM Lab summer 2018 intern, entering OSU undergrad

Cold Fingers and Carabiners: that’s what most of the past three weeks have been about. We’ve progressively been getting up earlier—with many thanks to the coffee pot and multiple alarms— in order to be on the water collecting data before the wind and fog decide to kick in. Working on the ocean at 7 am with wet hands, metal equipment, a tight suit, and a “refreshing” breeze while trying to keep an eight-foot sit-on-top kayak from tipping over is challenging to say the least. Making sure the Theodolite is perfectly level on its tripod resting on sand-covered ground at the top of a cliff? Not much easier. The air is cold, the wind is cold, the equipment is cold, I’m cold, and now, everything is wet.

Rugged laptop on the cliff site. Photo by Hayleigh Middleton.

I absolutely love it.

Of all the ways I could have chosen to spend my summer before starting college at OSU, I’m so glad I took a chance and asked to spend it here. The official goals of our research project are to monitor and record the foraging habits of the Pacific Coast Feeding Group of gray whales, attempt to find out if specific individuals tend to have site fidelity and forage here year after year, and why or how they choose certain spots to feed over others. What does that mean for me? I get to kayak and take pictures of whales for six weeks! Of course, there’s a bunch of technical stuff and expensive equipment that took us two weeks to learn, but now we’re off to a great start and ready to learn more about these amazing creatures.

We have such a short amount of time to collect all this data to try and fill in the puzzle that is gray whale behavior, and we’re only a few weeks in, but I feel like I’ve already connected with this group of 60,000-pound mammals. That, in essence, is really what we’re doing here. We’re on top of a 33-meter-high cliff watching empty water for hours on the chance that we’ll be able to see a whale, identify it through photo-ID, track it with the theodolite to figure out its behavior, and use our kayak data to figure out its diet and feeding choices. Even though the whales forage up to two kilometers away from our tracking spot, it feels like they know we’re watching them. Sometimes it feels like they’re teasing us—we’ll see one, and once we get the sights fixed on it, it dives down and doesn’t come back up until we’ve turned our attention. One whale got into a very predictable pattern: three blows and then a deep dive, forage for five minutes, pop up half a viewfinder away, three more blows. We set our sights on the third blow and waited for her to resurface.

…and waited.

She swam away and didn’t show herself again.

Other times it’s like they conspire against us. Earlier this week, we spent most of the morning tracking the same whale. A couple hours into the track, another whale popped up right next to the first. Since we use a computerized tracking program, each whale is assigned a group number. That way, we can track each individual’s path and later match it to the photo identification database and sometimes a nickname. The two whales surfaced at just the right frequency and distance apart that deciding which number was currently up was guesswork for a good 15 minutes, but we gave them new track numbers and were able to sort it out later after reviewing our photos.

Searching for whales. Photo by Haley Kent.

On another day, we surveyed for whales until quitting time, which is 3:00 pm. About 2:30 pm, one was finally spotted. I named her Princess because she couldn’t be bothered to bring her body out of the water enough so we could mark her location or take a picture except for when her pectoral fin, the tip of which was “gloved” in white, came out and made a motion like a princess in a parade. When there are whales around, we can’t just say “oh look, 3:00 pm time to go” because this is important data to collect. So, we decided to wait until 3:30 pm to see if she surfaced again within visual range. 3:30 pm came and still no sign of her, so I packed up the theodolite and tripod. As soon as the box was closed, she blew, and another whale surfaced right in front of the cliff. We got some pictures of the closer one for a bit and decided that was enough. As the camera was being lowered into its case, another whale surfaced in the cove. It felt like the first went and told all the whales heading south “hey, these guys want to leave at 3, so show up right around then.” That day we got back to the lab around 5. Even though this meant being on the cliff for almost 10 hours that day, it was thrilling to have seen so many whales in one day.

Then there are times when the whales seem to beg for attention. On our third day on the cliff, we saw what we believe to be a juvenile come swimming into view. We assume that he was a juvenile because he was “small” and quite blank in terms of pigmentation and scarring. He was adorable. He stayed over at Mill Rocks for a while foraging, all of which we “fixed” into the tracking program via the Theodolite, and then he came toward us into the little kelp patch just in front of our cliff site. He would dive down, scoop up some zooplankton to eat, and resurface right in the middle of the kelp. The cutest part is that he would then proceed to roll around in the kelp and further drape himself in it.

Having such a young whale come and forage made us wonder if mothers who have site fidelity then teach their young “hey, you don’t have to go all the way north, there’s a ton of good food here in Port Orford.” Hopefully that’s one of the things we’ll be able to figure out with the data collected with this long–term study. But in the meantime, I still have three weeks of data to collect and a bunch more whales to meet.

Are bacteria important? What do we get by analyzing microbiomes?

By Leila Lemos, PhD candidate, Fisheries and Wildlife Department, OSU

As previously mentioned in one of Florence’s blog posts, the GEMM Lab holds monthly lab meetings, where we share updates about our research and discuss articles and advances in our field, among other activities.

In a past lab meeting we were asked to bring an article to discuss that had inspired us in the past to conduct research in the marine field or in our current position. I brought to the meeting a literature review regarding methodologies to overcome the challenges of studying conservation physiology in large whales [1]. This article discusses different non-invasive or minimally invasive matrices (e.g., feces, blow, skin/blubber) that can be gathered from whales, and what types of analyses could be carried out, as well as their pros and cons.

One of the possible analyses that can be performed with fecal samples that was discussed in the article is the gut microflora (i.e., bacterial gut community) via genetic analysis. Since my PhD project analyzes fecal samples to determine/quantify stress responses in gray whales, we have since discussed the possibility of integrating this extra parameter to our analysis.

But… what is the importance of analyzing the gut microflora of a whale? What is the relationship between microflora and stress responses? Should we really use our limited sample size, time and money to work on this extra analysis? In order to be able to answer all of these questions, I began reading some articles of the field to better understand its importance and what kind of research questions this analysis can answer.

The gut of a mammal comprises a natural habitat for a large and dynamic community of bacteria [2] that is first developed in early life. Colonization of facultative bacteria (i.e., aerobic bacteria) begins at birth [3], and later, anaerobic bacteria also colonizes the gut. In humans, at the age of 1 year old, the microbiome should have a stable adult-like signature (Fig. 1).

Figure 01: Development of the microbiome in early life.
Source: [3]

The gut bacterial community is important for the physiology and pathology of its host and plays an important role in mammal digestion and health [2], responsible for many metabolic activities, including:

fermentation of non-digestible dietary residue and endogenous mucus [2];
recovery of energy [2];
recovery of absorbable nutrients [2];
cellulose digestion [4];
vitamin K synthesis [4];
important trophic effects on intestinal epithelia (cell proliferation and differentiation) [2];
angiogenesis promotion [4];
enteric nerve function [4];
immune structure [2];
immune function [2];
protection of the colonized host against invasion by alien microbes (barrier effect) [2];

Despite all the benefits, the bacterial community might also be potentially harmful when changes in the community composition (i.e., dysbiosis) occur due to the use of antibiotics, illness, stress, aging, lifestyle, bad dietary habits [4], and prolonged food and water deprivation [5]. Thus, potential pathological disorders might emerge when the microbiome community changes, such as allergy, obesity, diabetes, autism, multisystem organ failure, gastrointestinal and prostate cancers, inflammatory bowel diseases (IBD), and cardiovascular diseases [2, 4].

Changes in gut bacterial composition may also alter the brain-gut axis and the central nervous system (CNS) signaling [3]. More specifically, the core pathway affected is the hypothalamic-pituitary-adrenal (HPA) axis, which is activated by physical/psychological stressors. According to a previous study [6], the microbial community in the gut is critical for the development of an appropriate stress response. In addition, the microbial colonization in early life should occur within a certain time window, otherwise an abnormal development of the HPA axis might happen.

However, the gut microbiome can not only affect the HPA axis, but the opposite can also occur [3]. Signaling molecules released by the axis can alter the gastrointestinal (GIT) environment (i.e., motility, secretion, and permeability) [7]. Stress responses, as well as diseases, may also alter the gut permeability, causing the bacteria to cross the epithelial barrier (reducing the overall numbers of bacteria in the gut), activating immune responses that also alter the composition of the bacterial community in the gut [8, 9].

Figure 02: Communication between the brain, gut and microbiome in a healthily and in a stressed or diseased (mucosal inflammation) mammal.
Source: [3]

Thus, when thinking about whales, monitoring of the gut microflora might allow us to detect changes caused by factors such as aging, illness, prolonged food deprivation, and stressful events [2, 5]. However, since these are two-way factors, it is important to find an association between bacterial composition alterations and stressful events, such as the presence of predators (e.g., killer whales), illness (e.g., bad body condition), prolonged food deprivation (e.g., low prey availability and high competition), noise (e.g., noisy vessel traffic, fisheries opening and seismic surveys), and stressful reproductive status (e.g., pregnancy and lactating period). Examination of possible shifts in the gut microflora may be able to detect and be linked to many of these events, and also forecast possible chronic events within the population. In addition, the bacterial community monitoring study could aid in validating the hormone data (i.e., cortisol) we have been working with.

Therefore, the main research questions that arise in this context that can aid in elucidating the stress physiology in gray whales are:

What is the microflora community content in guts of gray whales along the Oregon coast?
Is it possible to detect shifts in the gut microflora from our gray fecal samples over time?
How do gut microflora and cortisol levels correlate?
Am I able to correlate shifts in gut microflora with any of the stressful events listed above?

We can answer so many other questions by analyzing the microbiome of baleen whales. Microbiomes are mainly correlated with host diet [10], so the composition of a microbiome can be associated with specific diets and functional gut capacity, and consequently, be linked to other animal populations, which helps to decode evolutionary questions. Results of a previous study on baleen whale microbiomes [10] point out that whales harbor unique gut microbiomes that are actually similar to those of terrestrial herbivores. Baleen whales and terrestrial herbivores have a shared physical structure of the GIT tract itself (i.e., multichambered foregut) and a shared hole for fermentative metabolisms. The multichambered foregut of baleen whales fosters the maintenance of the gut microbiome that is capable of extracting relatively unavailable nutrients from zooplankton (i.e., chitin, “sea cellulose”).

Figure 03: The similarities between whale and other terrestrial herbivore gut microbiomes: sea and land ruminants.
Source: [11]

Thus, the importance of studying the gut microbiome of a baleen whale is clear. Monitoring of the bacterial community and possible shifts can help us elucidate many questions regarding diet, overall health, stress physiology and evolution. Thinking about my PhD project, it may also help in validating our cortisol level results. I am confident that a microbiome analysis would significantly enhance my studies on the health and ecology of gray whales.

References

Hunt, K.E., et al., Overcoming the challenges of studying conservation physiology in large whales: a review of available methods.Conservation Physiology, 2013. 1: p. 1-24.
Guarner, F. and J.-R. Malagelada, Gut flora in health and disease.The Lancet, 2003. 360: p. 512–519.
Grenham, S., et al., Brain–gut–microbe communication in health and disease.Frontiers in Physiology, 2011. 2: p. 1-15.
Zhang, Y., et al., Impacts of Gut Bacteria on Human Health and Diseases.International Journal of Molecular Sciences, 2015. 16: p. 7493-7519.
Bailey, M.T., et al., Stressor exposure disrupts commensal microbial populations in the intestines and leads to increased colonization by Citrobacter rodentium.Infection and Immunity, 2010. 78: p. 1509–1519.
Sudo, N., et al., Postnatal microbial colonization programs the hypothalamic-pituitary-adrenal system for stress response in mice.The Journal of Physiology, 2004. 558: p. 263–275.
Rhee, S.H., C. Pothoulakis, and E.A. Mayer, Principles and clinical implications of the brain–gut–enteric microbiota axis Nature Reviews Gastroenterology & Hepatology, 2009. 6: p. 306–314.
Kiliaan, A.J., et al., Stress stimulates transepithelial macromolecular uptake in rat jejunum.American Journal of Physiology, 1998. 275: p. G1037–G1044.
Dinan, T.G. and J.F. Cryan, Regulation of the stress response by the gut microbiota: Implications for psychoneuroendocrinology.Psychoneuroendocrinology 2012. 37: p. 1369—1378.
Sanders, J.G., et al., Baleen whales host a unique gut microbiome with similarities to both carnivores and herbivores.Nature Communications, 2015. 6(8285): p. 1-8.
El Gamal, A. Of whales and cows: the baleen whale microbiome revealed. Oceanbites 2016[cited 2018 07/31/2018]; Available from: https://oceanbites.org/of-whales-and-cows-the-baleen-whale-microbiome-revealed/.

How to apply my PhD?

By Leila Lemos, PhD candidate, Fisheries and Wildlife Department

Time has flown. It seems that it was like a month ago that I received the news that I was approved in a public notice from the Brazilian government to study abroad, and began the process of moving to Oregon. But actually almost three years have now passed, and I am starting to wrap up my PhD, since I need to defend it in a little bit more than a year.

Our team is now starting the third and last fieldwork season for my PhD project. I am also working on my study plan to determine the last classes I need to take, and our first manuscripts are ‘in press’ or ‘in prep’ for submission to journals. So, it’s time for me to think about what comes next.

I am from Rio de Janeiro, Brazil, and I am studying in the US through a Brazilian government program called Science Without Borders. This program aims to send students abroad to learn new techniques and to develop innovative projects. The projects needed to be original to be approved by the public notice. The main idea is to bring these students back to Brazil, after their PhD completion, to disseminate the acquired knowledge by applying the learned techniques.

My project includes a few novel aspects that allowed for funding by this program. The main focus of my thesis is to develop an endocrinology study of a cetacean species. This was (and still is) a critical field in Brazil, as reported by the “National Action Plan for the conservation of aquatic mammals: Small cetaceans” (2010). According to this Action Plan, cetacean hormonal analyses are rare and of high priority, but there are limited labs with the capacity to study cetacean endocrinology in Brazil. Other limiting factors are the associated analysis costs and a lack of human knowledge and skills. In addition to the hormonal analyses (Figure 1), I am also using other ‘new technologies’ in the project: drones (Figure 2; Video 1) and GoPros (Video 2).

Figure 1: Learning how to perform hormonal analysis at the Seattle Aquarium, WA.
Source: Angela Smith

Figure 2: Learning how to fly a drone in Newport, OR.
Source: Florence Sullivan

Video 1: Drone flights performed in Newport, OR, during fieldwork in 2016.

* Taken under NOAA/NMFS permit #16111 to John Calambokidis.

Video 2: Video of mysid swarms during a GoPro deployment conducted in Port Orford, OR, during fieldwork in 2016.

The importance of studying cetacean hormones includes a better understanding of their reproductive cycles (i.e., sex hormones such as progesterone, testosterone and estradiol) and their physiological stress response (i.e., cortisol) to possible threats (e.g., acoustic pollution, contaminants, lack of prey). In addition, through photographs and videos recorded by drones we can conduct photogrammetry analysis to monitoring cetacean body condition, and through GoPro recordings of the water column we can assess prey availability. Changes in both body condition and prey can help us explaining how and why hormone levels vary.

Through my PhD I have obtained skills in hormone analysis, photogrammetry and video prey assessment by studying the logistically accessible and non-threatened gray whale (Eschrichtius robustus). During method development, these features are important to increase sample size and demonstrate feasibility. But now that the methodologies have proven successful, we can start applying them to other species and regions, and under different circumstances, to improve conservation efforts of threatened populations.

Many cetacean species along the Brazilian coast are threatened, particularly from fishing gear and vessel interactions, chemical and noise pollution. By applying the methods we have developed in the GEMM Lab during my PhD to cetacean conservation issues in Brazil, we could enable a great expansion in knowledge across many fields (i.e., endocrinology, behavior, photogrammetry, diet). Additionally, these skills can promote safer work environments (for the scientist and for the object of study) and cheaper work processes. However, many countries, such as Brazil, do not have the infrastructure and access to technologies to conduct these same analyses, as in developed countries like the USA. These technologies, when sold in Brazil, have many taxes on the top of the product that they can become an extra hurdle, due to budget constraints. Thus, there is a need for researchers to adapt these skills and technologies, in the best manner possible, to the reality of the country.

Now that I am starting to think about ‘life after PhD’, I can see myself returning to my country to spread the knowledge, technologies and skills I have gained through these years at OSU to new research projects so that I am able to assist with conservation efforts for the ocean and marine fauna in Brazil.

References:

PAN, 2010. Plano de ação nacional para a conservação dos mamíferos aquáticos: pequenos cetáceos / André Silva Barreto … [et al.]; organizadores Claudia Cavalcante Rocha-Campos, Ibsen de Gusmão Câmara, Dan Jacobs Pretto. – Brasília: Instituto Chico Mendes de Conservação da Biodiversidade, Icmbio, 132 p. Em: <http://www.icmbio.gov.br/portal/images/ stories/docs-plano-de-acao/pan-peqs-cetaceos/pan_pequenoscetaceos_web.pdf> Acessado em: 27 de Maio de 2015.

Oregon sea otter reintroduction: opinions, perspectives, and theories

By Dominique Kone, Masters Student in Marine Resource Management

Species reintroductions can be hotly contested issues because they can negatively impact other species, ecosystems, and society, as well as failing, altogether. The uncertainty of their outcomes forces stakeholder groups to form their own opinions on whether it’s a good idea to proceed with a reintroduction. When you have several groups with conflicting values and views, managers need to focus on the information most important for them to make a well-informed decision on whether to pursue a reintroduction.

As researchers, we can play an important role by carefully considering and addressing these views through our research, if the appropriate data is available. Despite being in the early days of our study on the potential sea otter reintroduction to Oregon, we have already heard several perspectives regarding its potential success, the type of research we should do, and if sea otters should be brought back to Oregon. Here, I present some of the most interesting and relevant opinions, perspectives, and theories I’ve heard regarding this reintroduction idea.

The first reintroduction failed because of X, Y, and Z.

From 1970-1971, managers translocated 93 sea otters to Oregon in a reintroduction effort (Jameson et al. 1982). However, in a matter of 5-6 years, all sea otters disappeared, and the effort was considered a failure. Researchers have theorized that sea otters left Oregon due to a lack of suitable habitat and prey, or to return home to sites from which they were captured. Others have reasoned that managers should have introduced southern sea otters instead of northern sea otters, suggesting one subspecies’ genetic pre-disposition may improve their chance for survival.

Knowing the reasons for this failure may help managers avoid these causes in a future reintroduction attempt and increase its chance of success. We, as scientists, can also gain insight from knowing these causes because this may help us better tailor our research to potentially investigate whether those causes still pose a threat to sea otters during a second attempt. Unfortunately, we lack concrete evidence on what exactly caused this failure, but we can still work to test some these theories.

An otter is an otter, no matter where you put it.

There is evidence that northern and southern sea otters are genetically distinct, to a certain degree (Valentine et al. 2008, Larson et al. 2012), and hypotheses have been put forward that the two subspecies may be behaviorally- and ecologically-distinct, too. Studies have shown that northern and southern sea otters have different sized and shaped skulls and teeth, which researchers hypothesize may be a specialized foraging adaptation for consuming different prey species (Campbell & Santana 2017, Timm-Davis et al. 2015). This view suggests that each subspecies has developed unique traits to adapt to the environmental conditions specific to their current ranges. Therefore, when considering which subspecies to bring to Oregon, managers should reintroduce the subspecies with traits better-suited to cope with the types of habitat, prey assemblages, and oceanographic conditions specific to Oregon.

However, other scientists hold the opposite view, and argue that “an otter is an otter” no matter where you put it. This perspective suggests that both subspecies have an equal chance at surviving in any type of suitable habitat because all otters behave in similar ways. Therefore, ecologically, it may not matter which subspecies managers bring to Oregon.

Oregon doesn’t have enough sea otter habitat.

Kelp is considered important sea otter habitat. In areas with high sea otter densities, such as central and southern California, kelp forests are persistent throughout the year. However, in Oregon, our kelp primarily consists of bull kelp – a slightly more fragile species compared to the durable giant kelp in California. In winter, this bull kelp gets dislodged during intense storms, resulting in seasonal changes in kelp availability. Managers worry that this seasonality could reduce the amount of suitable habitat, to the point where Oregon may not be able to support sea otters.

Yet, we know sea otters used to exist here; therefore, we can assume there must have been some suitable habitat that may persist today. Furthermore, sea otters use a range of habitats, including estuaries, bays, and reefs (Laidre et al. 2009, Lafferty & Tinker 2014, Kvitek et al. 1988). Therefore, even during times when kelp is less abundant, sea otters could use these other forms of habitat along the Oregon coast. Luckily, we have the spatial tools and data to assess how much, where, and when we have suitable habitat, and I will specifically address this in my thesis.

They’ll eat everything!

Sea otters are famous for their voracious appetites for benthic invertebrates, some of which are of commercial and recreational importance to nearshore fisheries. In some cases, sea otters have significantly reduced prey densities, such as sea urchins and Dungeness crab (Garshelis & Garshelis 1984, Estes & Palmisano 1974). However, without a formal analysis, it’s difficult to know if sea otters will have similar impacts on Oregon’s nearshore species, as well as at spatial scale these impacts will occur and whether our fisheries will be affected. We can predict where sea otters are likely to occur based on the presence of suitable habitat, but foraging impacts could be more localized or widespread across sea otter’s entire potential range. To better anticipate these impacts, managers will need an understanding of how much sea otters eat, where foraging could occur based on the availability of prey, and where sea otters and fisheries are likely to interact. I will also address this concern in my thesis.

To reintroduce or not to reintroduce? That is the question.

I have found that many scientists and managers have strong opinions on whether it’s appropriate to bring sea otters back to Oregon. Those who argue against a reintroduction often highlight many of the theories already mentioned here – lack of habitat, potential impacts to fisheries, and genetics. While other opponents provided more logistical and practical justifications, such as confounding politics, as well as difficulties in getting public support and regulatory permission to move a federally-listed species.

In contrast, proponents of this idea argue that a reintroduction could augment the recovery of the species by providing additional habitat for the species to rebound to pre-exploitation levels, as well as allowing for increased gene flow between southern and northern sea otter populations. Other proponents have brought up potential benefits to humans, such restoring ecosystem services, providing an economic boost through tourism, or preserving tribal and cultural connections. Such benefits may be worth attempting another reintroduction effort.

As you can see, there are several opinions and perspectives related to a potential sea otter reintroduction to Oregon. While it’s important to consider all opinions, managers still need facts to make key decisions. Scientists can play an important role in providing this information, so managers can make a well-informed decision. Oregon managers have not yet decided whether to proceed with a sea otter reintroduction, but our lab is working to provide them with reliable and accurate science, so they may form their own opinions and arrive at their own decision.

References:

Estes, J. A. and J. F. Palmisano. 1974. Sea otters: the role in structuring nearshore communities. Science. 185: 1058-1060.

Garshelis, D. L. and J. A. Garshelis. 1984. Movements and management of sea otters in Alaska. The Journal of Wildlife Management. 48: 665-678.

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: 100-107.

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 Mammalogy. 90(4): 906-917.

Kvitek, R. G. ,Fukayama, A. K., Anderson, B. S., and B. K. Grimm. 1988. Sea otter foraging on deep-burrowing bivalves in a California coastal lagoon. Marine Biology. 98: 157-167.

Larson, S., Jameson, R., Etnier, M., Jones, T., and R. Hall. 2012. Genetic diversity and population parameters of sea otters, Enhydra lutris, before fur trade extirpation from 1741-1911. PLoS ONE. 7(3).

Timm-Davis, L. L, DeWitt, T. J., and C. D. Marshall. 2015. Divergent skull morphology supports two trophic specializations in otters (Lutrinae). PLoS ONE. 10(12).

Valentine et al. 2008. Ancient DNA reveals genotypic relationships among Oregon populations of the sea otter (Enhydra lutris). Conservation Genetics. 9:933-938.

The Recipe for a “Perfect” Marine Mammal and Seabird Cruise

By Alexa Kownacki, Ph.D. Student, OSU Department of Fisheries and Wildlife, Geospatial Ecology of Marine Megafauna Lab

Science—and fieldwork in particular—is known for its failures. There are websites, blogs, and Twitter pages dedicated to them. This is why, when things go according to plan, I rejoice. When they go even better than expected, I practically tear up from amazement. There is no perfect recipe for a great marine mammal and seabird research cruise, but I would suggest that one would look like this:

A Great Marine Mammal and Seabird Research Cruise Recipe:

A heavy pour of fantastic weather
- Light on the wind and seas
- Light on the glare
Equal parts amazing crew and good communication
A splash of positivity
A dash of luck
A pinch of delicious food
Heaps of marine mammal and seabird sightings
Heat to approximately 55-80 degrees F and transit for 10 days along transects at 10-12 knots

The end of another beautiful day at sea on the R/V Shimada. Image source: Alexa K.

The Northern California Current Ecosystem (NCCE) is a highly productive area that is home to a wide variety of cetacean species. Many cetaceans are indicator species of ecosystem health as they consume large quantities of prey from different levels in trophic webs and inhabit diverse areas—from deep-diving beaked whales to gray whales traveling thousands of miles along the eastern north Pacific Ocean. Because cetacean surveys are a predominant survey method in large bodies of water, they can be extremely costly. One alternative to dedicated cetacean surveys is using other research vessels as research platforms and effort becomes transect-based and opportunistic—with less flexibility to deviate from predetermined transects. This decreases expenses, creates collaborative research opportunities, and reduces interference in animal behavior as they are never pursued. Observing animals from large, motorized, research vessels (>100ft) at a steady, significant speed (>10kts/hour), provides a baseline for future, joint research efforts. The NCCE is regularly surveyed by government agencies and institutions on transects that have been repeated nearly every season for decades. This historical data provides critical context for environmental and oceanographic dynamics that impact large ecosystems with commercial and recreational implications.

My research cruise took place aboard the 208.5-foot R/V Bell M. Shimada in the first two weeks of May. The cruise was designated for monitoring the NCCE with the additional position of a marine mammal observer. The established guidelines did not allow for deviation from the predetermined transects. Therefore, mammals were surveyed along preset transects. The ship left port in San Francisco, CA and traveled as far north as Cape Meares, OR. The transects ranged from one nautical mile from shore and two hundred miles offshore. Observations occurred during “on effort” which was defined as when the ship was in transit and moving at a speed above 8 knots per hour dependent upon sea state and visibility. All observations took place on the flybridge during conducive weather conditions and in the bridge (one deck below the flybridge) when excessive precipitation was present. The starboard forward quarter: zero to ninety degrees was surveyed—based on the ship’s direction (with the bow at zero degrees). Both naked eye and 7×50 binoculars were used with at least 30 percent of time binoculars in use. To decrease observer fatigue, which could result in fewer detected sightings, the observer (me) rotated on a 40 minutes “on effort”, 20 minutes “off effort” cycle during long transits (>90 minutes).

Alexa on-effort using binoculars to estimate the distance and bearing of a marine mammal sighted off the starboard bow. Image source: Alexa K.

Data was collected using modifications to the SEEbird Wincruz computer program on a ruggedized laptop and a GPS unit was attached. At the beginning of each day and upon changes in conditions, the ship’s heading, weather conditions, visibility, cloud cover, swell height, swell direction, and Beaufort sea state (BSS) were recorded. Once the BSS or visibility was worse than a “5” (1 is “perfect” and 5 is “very poor”) observations ceased until there was improvement in weather. When a marine mammal was sighted the latitude and longitude were recorded with the exact time stamp. Then, I noted how the animal was sighted—either with binoculars or naked eye—and what action was originally noticed—blow, splash, bird, etc. The bearing and distance were noted using binoculars. The animal was given three generalized behavior categories: traveling, feeding, or milling. A sighting was defined as any marine mammal or group of animals. Therefore, a single sighting would have the species and the best, high, and low estimates for group size.

By my definitions, I had the research cruise of my dreams. There were moments when I imagined people joining this trip as a vacation. I *almost* felt guilty. Then, I remember that after watching water for almost 14 hours (thanks to the amazing weather conditions), I worked on data and reports and class work until midnight. That’s the part that no one talks about: the data. Fieldwork is about collecting data. It’s both what I live for and what makes me nervous. The amount of time, effort, and money that is poured into fieldwork is enormous. The acquisition of the data is not as simple as it seems. When I briefly described my position on this research cruise to friends, they interpret it to be something akin to whale-watching. To some extent, this is true. But largely, it’s grueling hours that leave you fatigued. The differences between fieldwork and what I’ll refer to as “everything else” AKA data analysis, proposal writing, manuscript writing, literature reviewing, lab work, and classwork, are the unbroken smile, the vaguely tanned skin, the hours of laughter, the sea spray, and the magical moments that reassure me that I’ve chosen the correct career path.

Alexa photographing a gray whale at sunset near Newport, OR. Image source: Alexa K.

This cruise was the second leg of the Northern California Current Ecosystem (NCCE) survey, I was the sole Marine Mammal and Seabird Observer—a coveted position. Every morning, I would wake up at 0530hrs, grab some breakfast, and climb to the highest deck: the fly-bridge. Akin to being on the top of the world, the fly-bridge has the best views for the widest span. From 0600hrs to 2000hrs I sat, stood, or danced in a one-meter by one-meter corner of the fly-bridge and surveyed. This visual is why people think I’m whale watching. In reality, I am constantly busy. Nonetheless, I had weather and seas that scientists dream about—and for 10 days! To contrast my luck, you can read Florence’s blog about her cruise. On these same transects, in February, Florence experienced 20-foot seas with heavy rain with very few marine mammal sightings—and of those, the only cetaceans she observed were gray whales close to shore. That starkly contrasts my 10 cetacean species with upwards of 45 sightings and my 20-minute hammock power naps on the fly-bridge under the warm sun.

Pacific white-sided dolphins traveling nearby. Image source: Alexa K.

Marine mammal sightings from this cruise included 10 cetacean species: Pacific white-sided dolphin, Dall’s porpoise, unidentified beaked whale, Cuvier’s beaked whale, gray whale, Minke whale, fin whale, Northern right whale dolphin, blue whale, humpback whale, and transient killer whale and one pinniped species: northern fur seal. What better way to illustrate these sightings than with a map? We are a geospatial lab after all.

Cetacean Sightings on the NCCE Cruise in May 2018. Image source: Alexa K.

This map is the result of data collection. However, it does not capture everything that was observed: sea state, weather, ocean conditions, bathymetry, nutrient levels, etc. There are many variables that can be added to maps–like this one (thanks to my GIS classes I can start adding layers!)–that can provide a better understanding of the ecosystem, predator-prey dynamics, animal behavior, and population health.

The catch from a bottom trawl at a station with some fish and a lot of pyrosomes (pink tube-like creatures). Image source: Alexa K.

Being a Ph.D. student can be physically and mentally demanding. So, when I was offered the opportunity to hone my data collection skills, I leapt for it. I’m happiest in the field: the wind in my face, the sunshine on my back, surrounded by cetaceans, and filled with the knowledge that I’m following my passion—and that this data is contributing to the greater scientific community.

Humpback whale photographed traveling southbound. Image source: Alexa K.

Can we talk about how cool sea otters are?

By Dominique Kone, Masters Student in Marine Resource Management

A couple of months ago, I wrote a blog introducing our new project, and my thesis, on the potential to reintroduce sea otters to the Oregon coast. In that blog, I expressed that in order to develop a successful reintroduction plan, scientists and managers need to have a sound understanding of sea otter ecology and the current state of Oregon’s coastal ecosystems. As a graduate student conducting a research-based thesis in a management program, I’m constantly fretting over the applicability of my research to inform decision-making processes. However, in the course of conducting my research, I sometimes forget just how COOL sea otters are. Therefore, in this blog, I wanted to take the opportunity to nerd out and provide you with my top five favorite facts about these otterly adorable creatures.

Without further ado, here are my top five favorite facts about sea otters:

Sea otters eat a lot. Previous studies show that an individual sea otter eats up to 30% of its own body weight in food each day[1][2]. With such high caloric demands, sea otters spend a great deal of their time foraging the seafloor for a variety of prey species, and have been shown to decrease prey densities in their local habitat significantly. Sea otters are famously known for their taste for sea urchins. Yet, these voracious predators also consume clams, sea stars, crabs, and a variety of other small invertebrate species[3][4].
Photo Credit: Katherine Johns via www.listal.com
Individuals are specialists, but can change their diet. Sea otters typically show individual foraging specialization – which means an individual predominantly eats a select few species of prey. However, this doesn’t mean an otter can’t switch or consume other types of prey as needed. In fact, while individuals tend to be specialists, on a population or species level, sea otters are actually generalist predators[5][6]. Past studies that looked at the foraging habits of expanding sea otter populations show that as populations expand into unoccupied territory, they typically eat a limited number of prey. But as populations grow and become more established, the otters will start to diversify their diet, suggesting intra-specific competition[3][7].
Sea otters exert a strong top-down force. Top-down forcing is one of the most important concepts we must acknowledge when discussing sea otter ecology. With top-down forcing, consumers at the top of the food chain depress the trophic level on which they feed, and this feeding indirectly increases the abundance of the next lower trophic level, resulting in a cascading effect[8]. The archetype example of this phenomenon is the relationship between sea otters, sea urchins, and kelp forests. This relationship goes as follows: sea otters consume sea urchin, and sea urchins graze on kelp. Therefore, sea otters reduce sea urchin densities by direct predation, thereby mediating grazing pressure on kelp. This indirect effect allows kelp to grow more abundantly, which is why we often see relatively productive kelp forests when sea otters are present[9]. This top-down forcing also has important implications for the whole ecosystem, as I’ll explain in my next fact.
Pictured: sea urchin dominated seascape in habitat without sea otters. Photo Credit: BISHOPAPPS via Ohio State University.
Sea otters help restore ecosystems, and associated ecosystem services. In kelp habitat where sea otters have been removed, we often see high densities of sea urchins and low biomasses of kelp. In this case, sea urchins have no natural predators to keep their populations in check and therefore completely decimate kelp forests. However, what we’ve learned is that when sea otters “reclaim” previously occupied habitats or expand into unoccupied territory, they can have remarkable restorative effects because their predation on sea urchins allows for the regrowth of kelp forest[10]. Additionally, with the restoration of key ecosystems like kelp forests, we can see a variety of other indirect benefits – such as increased biodiversity, refuge for fish nurseries and commercially-important species, and carbon sequestration[11][12][13]. The structure of nearshore ecosystems and communities change drastically with the addition or removal of sea otters, which is why they’re often referred to as keystone species.
Photo Credit: University of California, Santa Barbara.
Sea otters are most often associated with coastal kelp forests, but they can also exist in other types of habitats and ecosystems. In addition to kelp dominated ecosystems, sea otters are known to use estuaries and bays, seagrass beds, and swim over a range of bottom substrates[14][15]. As evidenced by previous studies, sea otters exert similar top-down forces in non-kelp ecosystems, as they do within kelp forests. One study found that sea otters also had restorative effects on seagrass beds within estuaries, where they consumed different types of prey (i.e., crabs instead of urchins), demonstrating that sea otters play a significant keystone role in seagrass habitats as well [12]. Findings such as these are vitally important to understanding (1) where sea otters are capable of living relative to habitat characteristics, and (2) how recovering or expanding sea otter populations may impact ecosystems and habitats in which they don’t currently exist, such as the Oregon coast.

Pictured: sea otter swimming through eel grass at Elkhorn Slough, California. Photo Credit: Kip Evans Photography.

Well, there you have it – my top five favorite facts about sea otters. This list is by no means exhaustive of all there is to know about sea otter ecology, and isn’t enough information to develop an informative reintroduction plan. However, a successful reintroduction plan will rely heavily on these underlying ecological characteristics of sea otters, in addition to the current state of Oregon’s nearshore ecosystems. As someone who constantly focuses on the relationship between scientific research and management and conservation, it’s nice every now and then to take a step back and just simply appreciate sea otters for being, well, sea otters.

References:

[1] 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.

[2] Reidman, M. L. and J. A. Estes. 1990. The sea otter (Enhydra lutris): behavior, ecology, and natural history. United States Department of the Interior, Fish and Wildlife Service, Biological Report. 90: 1-126.

[3] Laidre, K.L. and R. J. Jameson. 2006. Foraging patterns and prey selection in an increasing and expanding sea otter population. Journal of Mammology. 87(4): 799-807.

[4] Estes, J. A., Jameson, R.J., and B. R. Rhode. 1982. Activity and prey election in the sea otter: influence of population status on community structure. The American Naturalist. 120(2): 242-258.

[5] Tinker, M. T., Costa, D. P., Estes, J. A., and N. Wieringa. 2007. Individual dietary specialization and dive behavior in the California sea otter: using archival time-depth data to detect alternative foraging strategies. Deep-Sea Research Part II. (54):330-342.

[6] Newsome et al. 2009. Using stable isotopes to investigate individual diet specialization in California sea otters (Enhydra lutris nereis). Ecology. 90(4): 961-974.

[7] Ostfeld, R. S. 1982. Foraging strategies and prey switching in the California sea otter. Oecologia. 53(2): 170-178.

[8] Paine, R. T. 1980. Food webs: linkage, interaction strength and community infrastructure. The Journal of Animal Ecology. 49(3): 666-685.

[9] Estes, J. A. and J.F. Palmisano. 1974. Sea otters: their role in structuring nearshore communities. Science. 185(4156): 1058-1060.

[10] Estes, J. A., and D. O. Duggins. 1995. Sea otters and kelp forests in Alaska: generality and variation in a community ecological paradigm. Ecological Monographs. 65(1): 75-100.

[11] Wilmers, C. C., Estes, J. A., Edwards, M., Laidre, K. L., and B. Konar. 2012. Do trophic cascades affect the storage and flux of atmospheric carbon? An analysis of sea otters and kelp forests. Frontiers in Ecology and the Environment. 10(8): 409-415.

[12] Hughes et al. 2014. Recovery of a top predator mediate negative eutrophic effects on seagrass. Proceedings of the National Academy of Sciences. 110(38): 15313-15318.

[13] Lee, L.C., Watson, J. C., Trebilco, R., and A. K. Salomon. Indirect effects and prey behavior mediate interactions between an endangered prey and recovering predator. Ecosphere. 7(12).

[14] 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 Mammalogy. 90(4): 906-917.

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

GEMM Lab 2017: A Year in the Life

By Dawn Barlow, MSc Student, Department of Fisheries and Wildlife

The days are growing shorter, and 2017 is drawing to a close. What a full year it has been for the GEMM Lab! Here is a recap, filled with photos, links to previous blogs, and personal highlights, best enjoyed over a cup of hot cocoa. Happy Holidays from all of us!

The New Zealand blue whale team in action aboard the R/V Star Keys. Photo by L. Torres.

Things started off with a bang in January as the New Zealand blue whale team headed to the other side of the world for another field season. Leigh, Todd and I joined forces with collaborators from Cornell University and the New Zealand Department of Conservation aboard the R/V Star Keys for the duration of the survey. What a fruitful season it was! We recorded sightings of 68 blue whales, collected biopsy and fecal samples, as well as prey and oceanographic data. The highlight came on our very last day when we were able to capture a blue whale surface lunge feeding on krill from an aerial perspective via the drone. This footage received considerable attention around the world, and now has over 3 million views!

A blue whale surfaces just off the bow of R/V Star Keys. Photo by D. Barlow.

In the spring Rachael made her way to the remote Pribilof Islands of Alaska to study the foraging ecology of red-legged kittiwakes. Her objectives included comparing the birds that reproduce successfully and those that don’t, however she was thrown a major curveball: none of the birds in the colony were able to successfully reproduce. In fact, they didn’t even build nests. Further analyses may elucidate some of the reasons for the reproductive failure of this sentinel species of the Bering Sea… stay tuned.

The 2017 Port Orford field team. Photo by A. Kownacki.

Florence is a newly-minted MSc! In June, Florence successfully defended her Masters research on gray whale foraging and the impacts of vessel disturbance. She gracefully answered questions from the room packed with people, and we all couldn’t have been prouder to say “that’s my labmate!” during the post-defense celebrations. But she couldn’t leave us just yet! Florence stayed on for another season of field work on the gray whale foraging ecology project in Port Orford, this time mentoring local high school students as part of the project. Florence’s M.Sc. defense!

Upon the gray whales’ return to the Oregon Coast for the summer, Leila, Leigh, and Todd launched right back into the stress physiology and noise project. This year, the work included prey sampling and fixed hydrophones that recorded the soundscape throughout the season. The use of drones continues to offer a unique perspective and insight into whale behavior.

Video captured under NOAA/NMFS permit #16111.

Solene with a humpback whale biopsy sample. Photo by N. Job.

Solene spent the austral winter looking for humpback whales in the Coral Sea, as she participated in several research cruises to remote seamounts and reefs around New Caledonia. This field season was full of new experiences (using moored hydrophones on Antigonia seamount, recording dive depths with SPLASH10 satellite tags) and surprises. For the first time, whales were tracked all the way from New Caledonia to the east coast of Australian. As her PhD draws to a close in the coming year, she will seek to understand the movement patterns and habitat preferences of humpback whales in the region.

A humpback whale observed during the 2017 coral sea research cruise. Photo by S. Derville.

This summer we were joined by two new lab members! Dom Kone will be studying the potential reintroduction of sea otters to the Oregon Coast as a MSc student in the Marine Resource Management program, and Alexa Kownacki will be studying population health of bottlenose dolphins in California as a PhD student in the Department of Fisheries and Wildlife. We are thrilled to have them on the GEMM Lab team, and look forward to seeing their projects develop. Speaking of new projects from this year, Leigh and Rachael have launched into some exciting research on interactions between albatrosses and fishing vessels in the North Pacific, funded by the NOAA Bycatch Reduction Engineering Program.

During the austral wintertime when most of us were all in Oregon, the New Zealand blue whale project received more and more political and media attention. Leigh was called to testify in court as part of a contentious permit application case for a seabed mine in the South Taranaki Bight. As austral winter turned to austral spring, a shift in the New Zealand government led to an initiative to designate a marine mammal sanctuary in the South Taranaki Bight, and awareness has risen about the potential impacts of seismic exploration for oil and gas reserves. These tangible applications of our research to management decisions is very gratifying and empowers us to continue our efforts.

In the fall, many of us traveled to Halifax, Nova Scotia to present our latest and greatest findings at the 22^nd Biennial Conference on the Biology of Marine Mammals. The strength of the lab shone through at the meeting during each presentation, and we all beamed with pride when we said our affiliation was with the GEMM Lab at OSU. In other conference news, Rachael was awarded the runner-up for her presentation at the World Seabird Twitter Conference!

GEMM Lab members present their research. From left to right, top to bottom: Amanda Holdman, Leila Lemos, Solène Derville, Dawn Barlow, Sharon Nieukirk, and Florence Sullivan.

Leigh had a big year in many ways. Along with numerous scientific accomplishments—new publications, new students, successful fieldwork, successful defenses—she had a tremendous personal accomplishment as well. In the spring she was diagnosed with breast cancer, and after a hard fight she was pronounced cancer-free this November. We are all astounded with how gracefully and fearlessly she navigated these times. Look out world, this lab’s Principle Investigator can accomplish anything!

This austral summer we will not be making our way south to join the blue whales. However, we are keenly watching from afar as a seismic survey utilizing the largest seismic survey vessel in the world has launched in the South Taranaki Bight. This survey has been met with considerable resistance, culminating in a rally led by Greenpeace that featured a giant inflatable blue whale in front of Parliament in Wellington. We are eagerly planning our return to continue this study, but that will hopefully be the subject of a future blog.

New publications for the GEMM Lab in 2017 include six for Leigh, three for Rachael, and two for Alexa. Highlights include Classification of Animal Movement Behavior through Residence in Space and Time and A sense of scale: Foraging cetaceans’ use of scale-dependent multimodal sensory systems. Next year is bound to be a big one for GEMM Lab publications, as Amanda, Florence, Solene, Leila, Leigh, and I all have multiple papers currently in review or revision, and more in the works from all of us. How exciting!

In our final lab meeting of the year, we went around the table to share what we’ve learned this year. The responses ranged from really grasping the mechanisms of upwelling in the California Current to gaining proficiency in coding and computing, to the importance of having a supportive community in graduate school to trust that the right thing will happen. If you are reading this, thank you for your interest in our work. We are looking forward to a successful 2018. Happy holidays from the GEMM Lab!

GEMM Lab members, friends, and families gather for a holiday celebration.

Meeting to disentangle factors influencing albatross bycatch in the deep-set Hawaii Longline Fishery

By Rachael Orben PhD., Research Associate in the Seabird Oceanography Lab and GEMM Lab

Seabird bycatch is a global problem (e.g. Anderson et al 2011). Humans like eating fish and seabirds do too. Fishing vessels provide a food source for seabirds through discards, bait, and target fish. Different types of fishing gear pose different risks for seabirds. The good news is there are things that we can do to decrease these risks.

Albatrosses and petrels are particularly vulnerable to being hooked by longlines as the baited hooks are set overboard. Albatrosses and petrels are long lived (e.g., Wisdom the 65-year-old Laysan Albatross) and have a limited number of off-spring. Therefore fishery mortalities can have devastating impacts on populations if left unchecked. Currently all 22 species of albatrosses have IUCN statuses ranging from Near Threatened to Critically Endangered.

North Pacific Albatrosses

Longlines are used to catch a number of target species including tuna, swordfish, halibut, black cod, and toothfish. Just like the diversity of species this type of fishing gear is used to catch, there are a number of ways to set long-lines and ways to mitigate seabird bycatch and a method that works well in one instance may not work so well in other places. Tori Lines (a.k.a. streamer lines), side setting, night setting, faster sinking lines, and discard regulations are a few of the methods used.

Tori lines work by scaring birds away from baited longline hooks while they sink. Once the hooks sink past a few meters albatrosses are not able to reach them. Photo by Ed Melvin/Washington Sea Grant

In early November, I had the opportunity to attend a workshop in Honolulu, Hawaii hosted by the Western Pacific Regional Fishery Management Council. The workshop was held due to a dramatic increase in black-footed albatross bycatch by the Hawaii deep-set longline fishery in 2015 and 2016 (see the figure below). It was our job to figure out why, or more realistically pave the path for future analysis and data collection to answer this question.

Recently Leigh Torres and I were funded by the NOAA Bycatch Reduction Engineering Program to characterize fine-scale fishery-albatross interactions using previously collected albatross tracking data and tracks of fishing boats processed in real time by Global Fishing Watch. The workshop provided the perfect opportunity for me to learn more about the Hawaii longline fisheries.

Reasons for Albatross Bycatch

Rates of bycatch can change due to many factors, including where or when the fish are being caught, subtle choices made by fishermen, changes in seabird distributions, changes in prey of fish or seabirds, and so on. So, it can be very challenging to pin-point the exact reasons for an increase in bycatch. But, across the North Pacific, 2015 and 2016, were very strange years oceanographically. There was the warm water phenomena known as ‘the Blob’ along with a strong El Niño, and a positive Pacific Decadal Oscillation (PDO). So perhaps, bycatch levels will drop off again as we move into a La Niña, but perhaps not. It is good to know that fishery managers and scientists are paying attention.

Implications

From the perspective of the fisherman in the Hawaiian longline fleet, albatrosses are hardly ever caught; they are pulled in at a barely perceptible level of less than one bird per set and only from about December to July. Although one occasional dead bird among the menagerie of fish doesn’t seem like much, it can add up: there are ~140 boats in the deep-set longline fleet, that set 40-52 million hooks a year, plus the multiple other fisheries and fleets encountered by albatrosses across the North Pacific, and enough albatrosses could be killed to make a difference in their population numbers. And, we need to also consider the cumulative impacts since fisheries aren’t the only threat (e.g., sea level rise, storm surges, introduced predators; see Bakker et al 2018).

Inspecting the Catch

On the morning of the last day of the workshop we took a field trip to the Honolulu Fish Market at Pier 38 in Honolulu where the Hawaiian long-line fishing vessels dock to offload and sell their catch. We checked out some of the boats, watched fish being craned off a vessel into a large cart and went inside the cooler room to see where the fish are auctioned.

In the cooler room, the catch from one vessel was laid out on brilliant blue pallets. The tails of each tuna were sliced so the deep pink color of the meat could be assessed. A core sample of each fish was laid out on an identification tag. Then the auctioneer and the buyers visited each fish, rapidly bidding on a price per pound. Their quick words were basically incomprehensible to my untrained ear.

The prize-catch of the fishery, and the fish that gets the highest price per pound, is the big eye tuna. A number of other large and beautiful pelagic species are also caught and sold including: long and narrow marlins, with their bills cut off for packing, side table size pomfrets, speckled white with red accents; and the distinctive blunt headed mahimahi, with yellow bellies. Once the fish are sold, they are moved out of the auction room, packed and loaded into the trucks that whisk them away toward markets and restaurants in Hawaii, the U.S. Mainland, and beyond.

Sustainable management of these commercially valuable fish is dependent on a better understanding of their pelagic ecosystem, including when, where, and why albatrosses interact with fishing vessels. Hopefully, our current research project will help to answer some of these questions.