Surprises from the field: Winter in the Falkland Islands

By Rachael Orben, Assistant Professor, Seabird Oceanography Lab

Fieldwork often comes with the unexpected. It is the reason why field work is so exciting – not only discovering something new about a species and ecosystem, but it is also often the catalyst for the development of novel ideas and projects. However, designing a successful field campaign to a new location (and acquiring funding) requires preconceived expectations that are not too far off from reality. Working with colonial breeding seabirds and pinnipeds has its advantages since these animals are predictably found at their colonies during the breeding period.  However, breeding failures can be worse than expected (see my blog on red-legged kittiwakes) and as I just learned, sometimes almost everything can be surprising.

At the end of August, I returned from a 6-week winter field campaign on Bird Island in the Falkland Islands led by Dr. Alastair Baylis a Senior Research Fellow at the South Atlantic Environmental Research Institute. We were there to study the fine-scale foraging ecology of South American fur seals. Despite a healthy research community in the Falklands, very little is known about South American fur seals in the region. Our time on Bird Island was probably the first time people had been on the island in winter since the days of sealing.

So, what did I find surprising?

I will list them here from slightly mundane to the very surprising.

1) First of all, it was winter and I expected it to be cold.

This is probably a case of me not doing my pre-field season research, but it was pleasantly not as cold as I expected. Generally, the temperatures were above freezing, which made doing everything much easier. Of course, I still wore lots of layers and drank lots of hot drinks, but overall it was fairly mild.  It was also less windy and less rainy than I had imagined and we had some beautiful sunny days.

2) I had hay fever!

Not something usually anticipated for winter field work, but the tussac grass was flowering and that left me with itchy eyes, a stuffy nose and lots of sneezes. I should mention that tussac grass is everywhere and many of the tussacs are taller than a person!

Now for the science surprises.

3) FEMALE Fur Seals took foraging trips That were much longer than we had anticipated.

We had a couple of females leave the colony and go on foraging trips for 10 days, others for ~2 weeks, and others for over 3 weeks! Previous work on the island indicated that female fur seals might take 4.1­ +/- 2 day trips (Thompson et al. 2003). Fortunately, we were on the island for the long-haul (6-weeks shower free) so we were able to wait them out and retrieve the tags (and the data) when the females came home. The differences in trip duration could simply reflect annual changes in prey availability, but we know very little about what fur seals are eating, especially during the winter (Baylis et al. 2013).

4) albatrosses were attending their colony.

As a reminder, this was the middle of winter. Generally, black-browed albatrosses do not return to their colonies until September since they lay eggs in October (Strange, 1992). There weren’t many birds the day we arrived in mid-July (n=9), but even so, that was odd enough that I began taking photos of the colony each day with the plan to count birds and quantify colony attendance.

…and for the most surprising of all…

5) South American Sea Lions males were killing and eating female South American fur seals!

We were slow to realize what was happening since it was so unexpected. After we deployed our tracking tags on fur seals we spent many hours at the colony simply observing. We started to see things that didn’t quite make sense. Females cautiously approaching the water. Male sea lions hanging out in the water. Then Dr. Baylis saw a male sea lion go up into the colony and grab a pup and eat it! Shortly after that, we saw two male sea lions chase a female out of the water and up the hill towards the colony. One male eventually came back down to a tide pool with a female he had killed in his mouth. From that point, it because very clear what was happening and we saw multiple kills.

It is unknown how often male southern sea lions eat fur seals, but it has been observed in the Falklands before, both in the 1970s and in more recent years (Gentry & Johnson 1981).  Worldwide, sea lions are known to occasionally eat fur seal pups (Gentry & Johnson 1981, Harcourt 1993, Bradshaw et al. 1998), but people have rarely observed sea lions predating females.

Our three scientific surprises are really what field work is all about. We came home with the tracking data we were hoping for and we came home with something arguably more valuable. We can use these new observations to make informed hypotheses about how marine predators fit into the ecosystem in ways that before our visit to Bird Island we would have never have expected. Hopefully, we will have a chance to go back!
References

Baylis AMM, Arnould JPY, Staniland IJ (2013) Diet of South American fur seals at the Falkland Islands. Marine Mammal Sci 30:1210–1219

Bradshaw CJA, Lalas C, Mcconkey S (1998) New Zealand sea lion predation on New Zealand fur seals. New Zealand Journal of Marine and Freshwater Research 32:101–104

Gentry RL, Johnson JH (1981) Predation by sea lions on northern fur seal neonates. Mammalia 45

Harcourt R (1993) Individual variation in predation on fur seals by southern sea lions (Otaria byronia) in Peru. Canadian Journal of Zoology 71:1908–1911

Strange, IJ (1992) Field Guide to the Wildlife of the Falkland Islands and South Georgia (Collins Pocket Guide)

Thompson DR, Moss S, Lovell P (2003) Foraging behaviour of South American fur seals Arctocephalus australis: extracting fine scale foraging behaviour from satellite tracks. Mar Ecol Prog Ser 260:285–296

Experiencing the Oregon Coast

By Dominique Kone, Masters Student in Marine Resource Management

An ecologist’s research may involve some combination of fieldwork and lab work. Yet, with modern advances in quantitative tools, such as models, computer-based research is becoming more popular. Furthermore, as the predictive capacity of models improve, they are becoming valuable to decision-makers to forecast how marine environments may respond to management decisions or phenomenon like climate change. While this type of research is important to society, I’ve often wondered if and how researchers may benefit by stepping away from their computer, every now and then, to observe the very subjects they’re studying.

For my thesis, I’m conducting an ecological assessment of a potential sea otter reintroduction to the Oregon coast. Through this work, I spend most of my time working at a desktop, analyzing spatial layers, and researching and synthesizing the literature. While I’ve learned a great deal about sea otters and the Oregon Coast, I felt that I needed to gain a better contextual understanding of this area, especially as someone from outside the region. Luckily, this summer, I had the perfect opportunity to explore this great state. Here, I share just some of the places I visited this past summer, what I’ve learned from my travels, and how these explorations have given me a deeper appreciation for the Oregon Coast and the implications of my research.

Source: Beachcombers NW.

For those of you unfamiliar with Oregon geography, the Oregon Coast is an expansive area stretching from Warrenton, which borders the Columbia River, in the north to the Oregon-California border just south of Brookings (approximately 362 miles). However, if we divide this area into three geographic regions – northern, central, and southern – some noticeable regional differences become apparent, both in terms of local topography and human use and visitation.

Relative to the northern and central coastlines, the geology of southern coastline (approximately Coos Bay to Brookings) is much more complex – comprising of rocky shorelines, sheltered coves and inlets, islands, and calm estuaries (overall, less sandy beaches). The region also appears to support a relatively higher biomass of macroalgae, including kelp. Taken altogether, the presence of these physical features appears to make the southern coast potentially suitable sea otter habitat, an important prerequisite of reintroduction efforts.

Pictured: Southern coastlines. Left: Samuel H. Boardman State Park near Brookings, OR. Right: Port Orford Heads State Park in Port Orford, OR. Source: Dominique Kone.

In contrast, the northern and central coastlines are predominantly comprised of sandy shorelines. However, these stretches of beaches are sometimes disrupted by complex and rocky habitat and have some of the largest estuaries and bays found along the entire Oregon Coast – such as Yaquina Bay, Tillamook Bay, and the Columbia River – all of which could also be potentially suitable habitat for sea otters. Furthermore, while you can find some kelp in these regions (i.e. Yaquina Head Lighthouse), these beds appear to be more dispersed and less dense than along the southern coast. By observing these features in person this summer, I came away with a much greater sense of just how biogeographically unique each of these regions is, as well as what it truly means for habitat to be “suitable”.

Pictured: Central coastlines. Left: Yaquina Head Marine Garden. Right: Agate Beach, OR. In this photo, Yaquina Head can be seen in the distance, demonstrating how quickly shorelines can change from sandy to rocky habitat in the northern and central regions. Source: Dominique Kone.

Aside from these physical characteristics, I also came away with a greater sense of the type of people who live and visit these regions. Along the Oregon Coast, dozens of towns, cities, unincorporated communities, and census-designated places are called home by some 653,112 people (State of Oregon. 2012). Yet, the southern coast is much less populated than the rest of the Oregon Coast. In fact, only 13% (people in Coos and Curry County) of the Oregon Coast population lives along the southern coast (State of Oregon. 2012). During my visit to the southern region, I noticed the typical beach-goers and overnight campers at various state parks, but there were not nearly as many in the northern and central regions. This demographic disparity is not surprising, given each region’s location in the state. The northern and central coasts are much closer to highly-populated cities such as Portland, Salem, Corvallis, and Eugene, potentially making them more accessible to weekend or seasonal visitors. In southern Oregon, the nearest in-land cities include Roseburg, Grants Pass, and Medford, but these populations pale in comparison to those in the central and northern regions.

Pictured: Beach-goers enjoying a pleasant stroll on Cannon Beach, OR. Source: Roger’s Inn.

After spending some time on the Oregon Coast, I wonder how these communities may be impacted by sea otters if they were to be reintroduced. Tourism and recreation are a huge part of the Oregon Coast lifestyle and economy. If managers were to bring sea otters back to Oregon, we could potential see an increase in visitation – as sea otters are an iconic and charismatic species – particularly to communities on the southern coast where sea otters may be more likely to establish. This increased tourism may come in the form of tourist redistribution from the northern and central coast to the southern region, an increase in overall tourists from all over the state, or even an influx from outside the state. Although these predictions are premature and based only on my recent observations, it is important to consider the societal impacts of sea otter reintroduction to our local communities.

To brings things back full circle, my coastal adventures provided me with a much deeper understanding of the uniqueness of the Oregon coast, as well as the people who call it home. Having this sound understanding is not only important for me as I conduct my research, but it is also vitally important for managers who are considering a sea otter reintroduction as this action could have coast-wide or localized impacts on these communities. If managers decide to move forward with a reintroduction effort, they could look at other regions along the U.S. west coast that currently have sea otters to assess how wildlife tourism is managed in these communities. For me, I’m glad I decided to step way from the computer to experience this beautiful area because it has provided me with a perspective I could not get from my data and models.

 

References:

State of Oregon. 2012. Natural Hazards Mitigation Plan: Region 1: Oregon Coast. Accessed here < https://www.oregon.gov/LCD/HAZ/docs/2.A.ORNHMP12-Reg1Profile.pdf >

A Summer of “Firsts” for Team Whale Storm

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

To many people, six weeks may seem like a long time. Counting down six weeks until your favourite TV show airs can feel like time dragging on slowly (did anyone else feel that way waiting for Blue Planet II to be released?). Or crossing off the days on your calendar toward that much-needed holiday that is still six weeks away can feel like an eternity. It makes sense that six weeks should feel like a long time. After all, six weeks are approximately a ninth of an entire year. Yet, I can assure you that if you asked anyone on my research team this summer whether six weeks was a long time, they would all say no.

As I watched each of my interns present our research to a room of 50 engaged community members (Fig. 1) after our six week research effort, I couldn’t help but feel an overwhelming sense of pride for all of them at how far they had come during the course of the field season.

Figure 1. Our audience at the community presentation on August 31. Photo by Leigh Torres.

On the very first day of our two-week training back in July, I gave my team an introductory presentation covering gray whales, their ecology, what the next six weeks would look like, how this project had developed and its results to date (Quick side-note here: I want to give a huge shout out to Florence and Leigh as this project would not be what it is today without their hard work and dedication as they laid the groundwork for it three years ago and have continued to improve and expand it). I remember the looks on my interns’ faces and the phrase that comes to mind is ‘deer in headlights’. It isn’t surprising that this was the case as this internship was the first time any of them had done marine mammal field work, or any kind of field work for that matter. It makes me think back to my first taste of field work. I was a fresh high school graduate and volunteering with a bottlenose dolphin research group. I remember feeling out of place and unsure of myself, both in terms of data collection skills but also having to live with the same people I had worked with all day. But as the first few days turned into the first few weeks, I grew into my role and by the end of my time there, I felt like an expert in what I was doing. Based on the confidence with which my interns presented our gray whale foraging ecology research to an audience just over a week ago, I know that they too had become experts in these short six weeks. Experts in levelling a theodolite, in sighting a blow several kilometres out from our cliff site, in kayaking in foggy conditions, in communicating effectively in high stress situations – the list goes on and on.

While you may have read the previous blog posts written by each of my interns in the last four weeks and thus have a sense of who they are, I want to tell you a little more about each of these hardworking undergraduates that played a large role in making this year’s Port Orford gray whale season so effective. Although we did not have any local high school interns this year, the whole team hails from Oregon, specifically from Florence, Sweet Home and Portland.

Figure 2. Haley on the cliff equipped with the camera waiting for a whale to surface. Photo by Cynthia Leonard.

Haley Kent (Fig. 2), my co-captain and Marine Studies Initiative (MSI) intern, an Environmental Science major, is going into her senior year at OSU this fall. She is focused and driven, which I know will enable her to pursue her dream of becoming a shark researcher (I can’t even begin to describe her excitement when we saw the thresher shark on our GoPro video). I couldn’t have asked for a better right hand person for my first year taking over this project and I am excited to see what results she will reveal through her project of individual gray whale foraging preferences. Also, Haley has a big obsession for board games and provided the team with many evenings of entertainment thanks to Munchkin and King of Tokyo.

Figure 3. Dylan in the stern of the kayak on a foggy day reeling down the GoPro stick on the downrigger. Photo by Haley Kent.

Dylan Gregory (Fig. 3) is transferring from Portland Community College and is going to be an OSU junior this fall. Not only was Dylan always extremely helpful in working with me to come up with ways to troubleshoot or fix gear, but his portable speaker and long list of eclectic podcasts always made him a very good cliff team partner. He was also Team Whale Storm’s main chef in the kitchen, and while some of his dishes caused tears & sweat among some team members (Dylan is a big fan of spices), there were never any leftovers, indicating how delicious the food was.

Figure 4. Robyn on one of our day’s off visiting the gigantic Redwoods in California. Photo by Haley Kent.

Robyn Norman (Fig. 4) will be a sophomore at OSU this fall and her commitment to zooplankton identification has been invaluable to the project. Last year when she was a freshman, Robyn was given our zooplankton samples from 2017, a few identification guides and instructions on how to use the dissecting microscope, before she was left to her own devices. Her level of independence and dedication as a freshman was incredible and I am very grateful for the time and skills she has given to this work. Besides this though, Robyn always brought an element of happiness to the room and I can speak on behalf of the rest of the team, that when she was gone for a week on a dive trip, the house did not feel the same without her.

Figure 5. Hayleigh Middleton at the community presentation. Her dry humour and quips earned her a lot of laughter from the audience keeping them entertained. Photo by Tom Calvanese.

Hayleigh Middleton (Fig. 5), a fresh high school graduate and freshly turned 18 during the project, is starting as a freshman at OSU this fall. She is extremely perceptive and would (thankfully) often remind others of tasks that they had forgotten to do (like take the batteries out of the theodolite or to mention the Secchi depth on the GoPro videos). I was very impressed by Hayleigh’s determination to continue working on the kayak despite her propensity for sea sickness (though after a few days we did remedy this by giving her raw ginger to chew on – not her favourite flavour or texture but definitely very, very effective!). She is inquisitive about almost everything and I know she will do very well in her first year at OSU.

Thank you, Team Whale Storm (Fig. 6), for giving me six weeks of your summer and for making my first year as project leader as seamless as it could have been! Without each and every one of you, I would not have been able to survey for 149.2 hours on the cliff, collect over 300 zooplankton samples, identify 31 gray whales, or launch a tandem kayak at 6:30 am every morning.

Figure 6. Team Whale Storm. Back row, from left to right: Haley Kent, Robyn Norman, Hayleigh Middleton, Dylan Gregory. Front row, from left to right: Tom Calvanese, Dr. Leigh Torres, Lisa Hildebrand. Photo by Mike Baran.

My interns were not the only ones to experience many “firsts” during this field season. I learned many new things for the first time right alongside them. While taking leadership is not a foreign concept to me, these six weeks were my first real experience of leading a project and a team for a sustained period of time. Managing teams, delegating tasks and compiling data felt gratifying because I felt like I was exactly where I should be (Fig. 7).

Figure 7. From left to right: Tom, myself, Hayleigh & Dylan on the cliff site looking for whales. Photo by Leigh Torres.
Figure 8. Haley & I on a cold evening out on the water but very excited to have gotten back the GoPro stick retrieved by divers after it had been stuck in a crevice for over 5 days. Photo by Lisa Hildebrand.

I dealt with many daunting tasks, yet thanks to the support of my interns, as well as Tom (Port Orford field station’s incredible station manager), Florence and Leigh, I learned how to resolve my problems: I fixed and replaced broken or lost gear (I am not a very mechanically inclined person; Fig. 8), budgeted food for five hungry people doing tiring field work (I’ve only ever budgeted for one person previously), and taught people how to use gear that I had not often used before (I can say now that the theodolite and I are friends, but this wasn’t the case for the first few weeks…).

 

Figure 9. Me with all the gear packed into the truck ready to leave Port Orford after the end of the field season. Photo by Haley Kent.

In the lead up to the summer field season this year, Leigh said to me, in one of the many emails we exchanged, that leading the project was a big task but that it was just six weeks long. She suggested that I rest up and get organised as much as I could ahead of time because, after all, the data collected this summer was going to be my thesis data, so I would want it to be as good as possible. Looking back, she couldn’t have been more right – the six weeks simply flew by, I did need the rest she had advised, and it definitely was a big task. I can’t wait for it to happen all over again next summer.

Looking through the scope: A world of small marine bugs

By Robyn Norman, GEMM Lab summer 2018 intern, OSU undergraduate

Although the average human may think all zooplankton are the same, to a whale, not all zooplankton are created equal. Just like us, different whales tend to favor different types of food over others. Thus, creating a meal perfect for each individual preference. Using a plankton net off the side of our kayak, each day we take different samples, hoping to figure out more about prey and what species the whales, we see, like best. These samples are then transported back to the lab for analysis and identification. After almost a year of identifying zooplankton and countless hours of looking through the microscope you would think I would have seen everything these tiny organisms have to offer.  Identifying mysid shrimp and other zooplankton to species level can be extremely difficult and time consuming, but equally rewarding. Many zooplankton studies often stop counting at 300 or 400 organisms, however in one very long day in July, I counted over 2,000 individuals. Zooplankton tend to be more difficult to work with due to their small size, fragility, and large quantity.

Figure 1. A sample fresh off the kayak in the beginning stages of identification. Photo by Robyn Norman.

A sample that looks quick and easy can turn into a never-ending search for the smallest of mysids. Most of the mysids that I have sorted can be as small as 5 mm in length. Being difficult to identify is an understatement. Figure 1 shows a sample in the beginning stages of analysis, with a wide range of mysids and other zooplankton. Different species of mysid shrimp generally have the same body shape, structure, size, eyes and everything else you can think of. The only way to easily tell them apart is by their telson, which is a unique structure of their tail. Their telsons cannot be seen with the naked eye and it can also be hard to find with a microscope if you do not know exactly what you are looking for.

 

Throughout my time identifying these tiny creatures I have found 9 different species of mysid from this gray whale foraging ecology project in Port Orford from the 2017 summer. But in 2018 three mysid species have been particularly abundant, Holmesimysis sculpta, Neomysis rayii, and Neomysis mercedis.

Figure 2. Picture taken with microscope of a Holmesimysis sculpta telson. Photo by Robyn Norman.

H. sculpta has a unique telson with about 18 lateral spines that stop as they reach the end of the telson (Figure 2). The end of the telson has 4 large spines that slightly curve to make a fork or scoop-like shape. From my own observations I have also noticed that H. sculpta has darker coloring throughout their bodies and are often heavily pregnant (or at least during the month of August). Neomysis rayii and Neomysis mercedis have been extremely difficult to identify and work with. While N. rayii can grow up to 65 mm, they can also often be the same small size as N. mercedis. The telsons of these two species are very similar, making them too similar to compare and differentiate. However, N. rayii can grow substantially bigger than N. mercedis, making the bigger shrimp easier to identify. Unfortunately, the small N. rayii still give birth to even smaller mysid babies, which can be confused as large N. mercedis. Identifying them in a timely manner is almost impossible. After a long discussion, we decided it would be easier to group these two species of Neomysis together and then sub-group by size. Our three categories were 1-10 mm, 11-15 mm, 16+ mm. According to the literature, N. mercedis are typically 11-15 mm meaning that anything over this size should be a N. rayii (McLaughlin 1980).

Figure 3. Microscopic photo of a gammarid. Photo source: WikiMedia.
Figure 4. Caprellidae found in sample with unique coloration. Photo by Robyn Norman.

While mysids comprise the majority of our samples, they are not the only zooplankton that I see. Amphipods are often caught along with the shrimp. Gammarids look like the terrestrial potato bug and can grow larger than some species of mysid (Fig. 3).

As well as, Caprellidae (Fig. 4) that remind me of little tiny aliens as they have large claws compared to their body size, making it hard to get them out of our plankton net. These impressive creatures are surprisingly hardy and can withstand long times in the freezer or being poked with tweezers under a microscope without dying.

In 2017, there was a high abundance of amphipods found in both of our study sites, Mill Rocks and Tichenor Cove. Mill Rocks surprisingly had 4 times the number of amphipods than Tichenor Cove. This result could be one of the possible reasons gray whales were observed more in Mill Rocks last year. Mill Rocks also has a substantial amount of kelp, a popular place for mysid swarms and amphipods. The occurrence of mysids at each of these sites was almost equal, whereas amphipods were almost exclusively found at Mill Rocks. Mill Rocks also had a higher average number of organisms than Tichenor Cove per samples, potentially creating better feeding grounds for gray whales here in Port Orford.

Analyzing the 2018 data I can already see some differences between the two years. In 2018 the main species of mysid that we are finding in both sites are Neomysis sp. and Holmesimysis sculpta, whereas in 2017 Alienacanthomysis macropsis, a species of mysid identified by their long eye stalks and blunt telson, made up the majority of samples from Tichenor Cove. There has also been a large decrease in amphipods from both locations compared to last year. Two samples from Mill Rocks in 2017 had over 300 amphipods, however this year less than 100 have been counted in total. All these differences in zooplankton prey availability may influence whale behavior and movement patterns. Further data analysis aims to uncover this possibility.

Figure 5. 2017 zooplankton community analysis from Tichenor Cove. There was a higher percentage and abundance of Neomysis rayii (yellow) and Alienacanthomysis macropsis (orange) than in Mill Rocks.
Figure 6. 2017 zooplankton community analysis from Mill Rocks. There was a higher abundance and percentage of amphipods (blue) and Holmesimysis sculpta (brown) than in Tichenor cove. Caprellidae (red) increased during the middle of the season, and decreased substantially towards the end.

The past 6 weeks working as part of the 2018 gray whale foraging ecology research team in Port Orford have been nothing short of amazing. We have seen over 50 whales, identified hundreds of zooplankton, and have spent almost every morning on the water in the kayak. An experience like this is a once in a lifetime opportunity that we were fortunate to be a part of. For the past few years, I have been creating videos to document important and exciting times in my life. I have put together a short video that highlights the amazing things we did every day in Port Orford, as well as the creatures that live just below the surface. I hope you enjoy our Gray Whale Foraging Ecology 2018 video with music by Myd – The Sun. 

Big Data: Big possibilities with bigger challenges

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

Did you know that Excel has a maximum number of rows? I do. During Winter Term for my GIS project, I was using Excel to merge oceanographic data, from a publicly-available data source website, and Excel continuously quit. Naturally, I assumed I had caused some sort of computer error. [As an aside, I’ve concluded that most problems related to technology are human error-based.] Therefore, I tried reformatting the data, restarting my computer, the program, etc. Nothing. Then, thanks to the magic of Google, I discovered that Excel allows no more than 1,048,576 rows by 16,384 columns. ONLY 1.05 million rows?! The oceanography data was more than 3 million rows—and that’s with me eliminating data points. This is what happens when we’re dealing with big data.

According to Merriam-Webster dictionary, big data is an accumulation of data that is too large and complex for processing by traditional database management tools (www.merriam-webster.com). However, there are journal articles, like this one from Forbes, that discuss the ongoing debate of how to define “big data”. According to the article, there are 12 major definitions; so, I’ll let you decide what you qualify as “big data”. Either way, I think that when Excel reaches its maximum row capacity, I’m working with big data.

Collecting oceanography data aboard the R/V Shimada. Photo source: Alexa K.

Here’s the thing: the oceanography data that I referred to was just a snippet of my data. Technically, it’s not even MY data; it’s data I accessed from NOAA’s ERDDAP website that had been consistently observed for the time frame of my dolphin data points. You may recall my blog about maps and geospatial analysis that highlights some of the reasons these variables, such as temperature and salinity, are important. However, what I didn’t previously mention was that I spent weeks working on editing this NOAA data. My project on common bottlenose dolphins overlays environmental variables to better understand dolphin population health off of California. These variables should have similar spatiotemporal attributes as the dolphin data I’m working with, which has a time series beginning in the 1980s. Without taking out a calculator, I still know that equates to a lot of data. Great data: data that will let me answer interesting, pertinent questions. But, big data nonetheless.

This is a screenshot of what the oceanography data looked like when I downloaded it to Excel. This format repeats for nearly 3 million rows.

Excel Screen Shot. Image source: Alexa K.

I showed this Excel spreadsheet to my GIS professor, and his response was something akin to “holy smokes”, with a few more expletives and a look of horror. It was not the sheer number of rows that shocked him; it was the data format. Nowadays, nearly everyone works with big data. It’s par for the course. However, the way data are formatted is the major split between what I’ll call “easy” data and “hard” data. The oceanography data could have been “easy” data. It could have had many variables listed in columns. Instead, this data  alternated between rows with variable headings and columns with variable headings, for millions of cells. And, as described earlier, this is only one example of big data and its challenges.

Data does not always come in a form with text and numbers; sometimes it appears as media such as photographs, videos, and audio files. Big data just got a whole lot bigger. While working as a scientist at NOAA’s Southwest Fisheries Science Center, one project brought in over 80 terabytes of raw data per year. The project centered on the eastern north pacific gray whale population, and, more specifically, its migration. Scientists have observed the gray whale migration annually since 1994 from Piedras Blancas Light Station for the Northbound migration, and 2 out of every 5 years from Granite Canyon Field Station (GCFS) for the Southbound migration. One of my roles was to ground-truth software that would help transition from humans as observers to computer as observers. One avenue we assessed was to compare how well a computer “counted” whales compared to people. For this question, three infrared cameras at the GCFS recorded during the same time span that human observers were counting the migratory whales. Next, scientists, such as myself, would transfer those video files, upwards of 80 TB, from the hard drives to Synology boxes and to a different facility–miles away. Synology boxes store arrays of hard drives and that can be accessed remotely. To review, three locations with 80 TB of the same raw data. Once the data is saved in triplet, then I could run a computer program, to detect whale. In summary, three months of recorded infrared video files requires upwards of 240 TB before processing. This is big data.

Scientists on an observation shift at Granite Canyon Field Station in Northern California. Photo source: Alexa K.
Alexa and another NOAA scientist watching for gray whales at Piedras Blancas Light Station. Photo source: Alexa K.

In the GEMM Laboratory, we have so many sources of data that I did not bother trying to count. I’m entering my second year of the Ph.D. program and I already have a hard drive of data that I’ve backed up three different locations. It’s no longer a matter of “if” you work with big data, it’s “how”. How will you format the data? How will you store the data? How will you maintain back-ups of the data? How will you share this data with collaborators/funders/the public?

The wonderful aspect to big data is in the name: big and data. The scientific community can answer more, in-depth, challenging questions because of access to data and more of it. Data is often the limiting factor in what researchers can do because increased sample size allows more questions to be asked and greater confidence in results. That, and funding of course. It’s the reason why when you see GEMM Lab members in the field, we’re not only using drones to capture aerial images of whales, we’re taking fecal, biopsy, and phytoplankton samples. We’re recording the location, temperature, water conditions, wind conditions, cloud cover, date/time, water depth, and so much more. Because all of this data will help us and help other scientists answer critical questions. Thus, to my fellow scientists, I feel your pain and I applaud you, because I too know that the challenges that come with big data are worth it. And, to the non-scientists out there, hopefully this gives you some insight as to why we scientists ask for external hard drives as gifts.

Leila launching the drone to collect aerial images of gray whales to measure body condition. Photo source: Alexa K.
Using the theodolite to collect tracking data on the Pacific Coast Feeding Group in Port Orford, OR. Photo source: Alexa K.

References:

https://support.office.com/en-us/article/excel-specifications-and-limits-1672b34d-7043-467e-8e27-269d656771c3

https://www.merriam-webster.com/dictionary/big%20data

Searching for seabirds on the Garden Island

By Erin Pickett, M.Sc. (GEMM Lab member 2014-2016)

Field Assistant, Kaua’i Endangered Seabird Recovery Project

I heaved my body up with both arms, swung one leg up and attempted to muster any remaining energy I had into standing on the ridgeline of the valley that I had just crawled out of. Soaked from the rain, face covered with bits of dirt and with ferns sticking out of my hair I probably resembled a creature crawling out of a swamp. I smiled at this thought knowing that my dramatic emergence from the swamp might have been captured on a nearby motion-sensing trail camera.

I surveyed my surroundings to gain my bearings. I was searching for seabird burrows in a densely vegetated valley called Upper Limahuli Preserve in the mountains of Kaua’i, Hawaii. I was looking for the nests of the endangered Hawaiian Petrel (or ‘Ua’u in Hawaiian) and the threated Newell’s Shearwater (A’o), Hawaii’s only two endemic (found nowhere else in the world) Procellarid species. I registered the trail, the nearby fence line and the two valleys on either side of the ridge I was standing on. If a drone had photographed me from above, the scene of lush green mountains, waterfalls and rugged cliffs would not only look like the views from the helicopter arrival scene in the movie Jurassic Park, but indeed was the same Nā Pali coastline.

Northeastern facing view from the trail at Upper Limahuli Preserve looking toward the author’s hometown of Kīlauea and the site of the Nihokū predator-fence at Kīlauea National Wildlife Refuge

When I finished my graduate program at Oregon State University in 2017, I began working for a project called the Kaua’i Endangered Seabird Recovery Project (KESRP). Our work at KESRP focuses on monitoring Kauai’s populations of breeding a’o and ‘ua’u, mitigating on-land threats through recovery activities and conducting research (e.g. habitat modeling & at-sea tracking) to learn more about the two species.

An estimated 90% of the Newell’s Shearwater population breeds on the island of Kaua’i, as does a large portion of the Hawaiian Petrel population. Both populations have declined rapidly on Kaua’i over the past two decades, where radar surveys found a 78% decrease of Hawaiian Petrels and a 94% decrease in overall numbers of Newell’s Shearwaters (Raine et al., 2017). Light pollution, collision with electrical power lines, and invasive vertebrate predators represent primary threats to both the a’o and ‘ua’u while on land during the breeding season. As with all seabirds that nest on islands, the a’o and ‘ua’u are easy prey for invasive species such as feral cats and black rats, thus, there is a large effort within our study area to alleviate the threat of these predators.

A ‘ua’u adult incubating an egg at Upper Limahuli Preserve, 2018

The purpose of my burrow search effort on this day was to find suitable candidate burrows for a translocation project that KESRP has undertaken since 2015. This fall, we will attempt to relocate via helicopter up to 20 a’o and ‘ua’u chicks from the mountains of Kaua’i, where they are vulnerable to invasive predators, to a predator-proof fenced area located within nearby Kīlauea National Wildlife Refuge. The ultimate aim of our translocation project, a critical component of the Nihokū Ecosystem Restoration Project, is to establish successful breeding colonies of a’o and ‘ua’u within the protected boundaries of a fence that is impermeable to rats, cats, and pigs.

On Kaua’i, the imperiled a’o and ‘ua’u nest on verdant cliffs amid native Hawaiian uluhe ferns and ‘ohi‘a lehua trees. Both species raise their chicks in burrows that can only be located by humans after an extensive search effort that involves scanning the densely vegetated forest floor for tiny feathers and guano trails, and following the musty scent of seabirds until an underground tunnel is found, sometimes with a bird nestled inside.

The author with an a’o chick that was relocated to the Nihokū Ecosystem Restoration Site in 2017

My afternoon of burrow searching had been strenuous, and being day three it had already been a long week in the field so I sighed and started heading in the direction that would lead me back to our field camp. Though, after a few steps I caught the musty smell of seabird in the air and immediately stopped walking. Like an animal, I followed my nose and turned my head over my right shoulder and sniffed the air. I climbed over the fence that separated the trail I was hiking on from the 3,000 foot drop into the valley below, carefully positioned my feet on the fragile cliff side and lifted a large tuft of grass to find a freshly dug hole that smelled unmistakably like a seabird.

A triumphant selfie by the author after finding a particularly difficult to locate a’o burrow

Either a prospecting Hawaiian Petrel or Newell’s Shearwater had broken ground on this new burrow the night before. The birds had been busy digging into the cliff side while I had been conducting an auditory survey a few hundred meters away. The auditory survey had begun at sunset and over the course of the next two hours I listened for and recorded the locations of seabirds transiting overhead, heading from the sea to the mountains and calling from their burrows nearby. Ideally, this auditory survey would help me pinpoint locations of ‘ground callers’ who’s raucous would lead me to their burrows the next day.

Finding a burrow is not often as easy as pinpointing the location of a ground caller, catching a whiff of seabird near that location and immediately locating a hole in the ground. Yet, finding a burrow that is ‘reachable’ and that is reasonably close to a helicopter landing zone, is even more difficult. And this task is one of our objectives throughout the field season this year.

If you’re interested in keeping up with our progress you can follow KESRP on Facebook: https://www.facebook.com/kauaiseabirdproject/

Reference(s):

Raine, A. F., Holmes, N. D., Travers, M., Cooper, B. A., & Day, R. H. (2017). Declining population trends of Hawaiian Petrel and Newell’s Shearwater on the island of Kaua‘i, Hawaii, USA. The Condor119(3), 405-415.

Methods in UAS marine mammal research from coast to coast

By Julia Stepanuk, PhD student, department of Ecology and Evolution, Stony Brook University

Hello GEMM Lab blog readers! I’m a PhD student in Lesley Thorne’s lab at Stony Brook University in New York and I spent this past week with the GEMM Lab learning their protocol for drone flights and gaining experience flying over whales. I saw my first gray whales just off the coast of Newport, Oregon and assisted with the GEMM Lab’s summer field research. We luckily had 4 days of great weather in a row, so I got tons of experience conducting research that integrates drone flights that I can bring home to our lab. It was really exciting to observe and learn from the well-oiled machine that is the GEMM Lab. Information about their gray whale project can be found here and here, but I want to focus on how my experiences here in Newport can translate to my research interests off the coast of Long Island.

Gray whale off the Newport, Oregon coast. Photo by Julia Stepanuk, under NMFS/NOAA permit # 16111

Our lab in New York has a range of interesting projects currently underway: we study everything from decadal trends in sea turtle diets to how frequently herring gulls visit urban habitats for food around New York City. My research focuses on the whales around New York, specifically humpback whales. Humpback whales are very well studied in many parts of the world, especially in the Northwest Atlantic. The initial photo-identification studies were conducted in the Gulf of Maine in the 1970s (Katona et al., 1979), and the North Atlantic Humpback Whale Catalogue is still going strong with over 8,000 individual whales catalogued! Recently though, many people have reported humpback whales in a new area: the waters around New York and Long Island. Yet, we don’t understand how these whales fit in with the rest of the humpback population in the North Atlantic. We do know that they feed along the shores of New York City and Long Island, and they are primarily consuming menhaden (also known as bunker or pogy), a forage fish that is vital to both our economic and environmental systems in the Northeast U.S. (see: Six reasons why menhaden is the greatest fish we ever fished).

Opportunistic humpback whale sightings, NYS GIS Data
Menhaden, https://maineguides.com/maine-saltwater-fish-species/atlantic-menhaden/

 

The habitat use and behavior of humpbacks in this part of the world is important for two reasons: 1) this population of humpback whales has recovered from the detrimental population-level impacts of industrial whaling in the 18th and 19th centuries, and thus was recently delisted from the endangered species list; and 2) humpback whales in the Northwest Atlantic are at-risk from ship strikes and fishing gear entanglement, so much so that NOAA declared an unusual mortality event for 2016-2018. In fact, 4 humpback whales washed up dead on the shore of Long Island in the last 30 days! These facts lead to my motivation for my PhD studies: where are humpback whales in the vicinity of New York City and how do they use the environment around Long Island? I specifically want to investigate the trophic relationship between humpback whales and menhaden.

Humpback whale feeding off the Rockaways, Long Island; Artie Raslich

There are a number of studies where researchers have used photogrammetry from drones to document the body condition of marine mammal species (Burnett et al., in press; Christiansen et al., 2016; Christiansen et al., 2018; Dawson et al., 2017; Perryman and Lynn., 2002), which I plan to extend to the humpback whales around Long Island. I will conduct photogrammetry of the humpback whales off Long Island and will document the individual whales, their behaviors, and their prey sources. Because scientists are now documenting and monitoring body condition of humpback whales in many parts of the world, we can compare the overall health and body condition of humpbacks in New York to those in other habitats. Further, by documenting the schools of menhaden they are consuming, we can better assess the trophic relationship between humpbacks and menhaden in a foraging habitat adjacent to one of the largest cities on the planet.

Drone imagery off Long Island from a recreational drone pilot in 2017. Top: two humpback whales next to a dense school of menhaden. Middle: two humpback whales with pectoral fins clearly visible. Bottom: humpback whales lunge feeding from above; http://fireislandandbeyond.com/video-pair-of-humpback-whales-between-old-inlet-and-davis-park-fire-island-ny/2/

 

I am so grateful to the GEMM Lab for sharing information and skills with me over the past week and am excited to bring my new skillset back to our lab at Stony Brook! Aside from drone skills, I learned that gray whales are very flexible, and their mottled skin is absolutely beautiful! I also learned that my peanut butter and jelly sandwich making skills are passable (you have to find a way to keep the jelly from leaking through the bread on a hot day on a boat!) and I learned how to collect fecal samples from whales (put a net in the water, and scoop up the pieces of whale poo). I am also now hooked on the FIFA World Cup matches and will be losing lots of sleep in the next few weeks while I diligently follow my new favorite teams. Thank you again to the GEMM lab for being so supportive and welcoming! For an influx of east coast megafauna research, follow the Thorne Lab blog as our many spatial marine megafauna projects get underway, and follow me on twitter as I pursue a PhD!

 

References

Burnett, J.D., Lemos, L., Barlow, D.R., Wing, M.G., Chandler, T.E. & Torres, L.G. (in press) Estimating morphometric attributes of baleen whales with photogrammetry from small UAS: A case study with blue and gray whales. Marine Mammal Science.

Christiansen, F., Dujon, A.M., Sprogis, K.R., Arnould, J.P.Y., Bejder, L., 2016. Noninvasive unmanned aerial vehicle provides estimates of the energetic cost of reproduction in humpback whales. Ecosphere 7

Christiansen, F., Vivier, F., Charlton, C., Ward, R., Amerson, A., Burnell, S., Bejder, L., 2018. Maternal body size and condition determine calf growth rates in southern right whales. Marine Ecology Progress Series 592, 267–281.

Dawson, S.M., Bowman, M.H., Leunissen, E., Sirguey, P., 2017. Inexpensive Aerial Photogrammetry for Studies of Whales and Large Marine Animals. Front. Mar. Sci. 4.

Katona, S., B. Baxter, 0. Brazier, S. Kraus, J. Perkins AND H. Whitehead. 1979. Identification of humpback whales by fluke photographs. Pages 33-44 in H.E. Winn and B.L. Olla, eds. Behavior of marine animals. Current perspectives in research. Vol. 3: Cetaceans. Plenum Press. New York.

Perryman WL, Lynn MS. 2002. Evaluation of nutritive condition and reproductive status of migrating gray whales (Eschrichtius robustus) based on analysis of photogrammetric data. J. Cetacean Res. Manage. 4(2):155-164.

 

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.

“The joy of paper acceptance” or “The GEMM Lab’s recent scientific contributions”

Dr. Leigh Torres, Geospatial Ecology of Marine Megafauna Lab, Marine Mammal Institute, Oregon State University

The GEMM Lab is always active – running field projects, leading outreach events, giving seminars, hosting conferences, analyzing data, mentoring young scientists, oh the list goes on! (Yes, I am a proud lab PI). And, recently we have had a flurry of scientific papers either published or accepted for publication that I want to highlight. These are all great pieces of work that demonstrate our quality work, poignant and applied science, and strong collaborations. For each paper listed below I provide a short explanation of the study and implications. (Those names underlined are GEMM Lab members, and I provided a weblink where available.)

 

Sullivan, F.A. & Torres, L.G. Assessment of vessel disturbance to gray whales to inform sustainable ecotourism. The Journal of Wildlife Management, doi:10.1002/jwmg.21462.

This project integrated research and outreach regarding gray whale behavioral response to vessels. We simultaneously tracked whales and vessels, and data analysis showed significant differences in gray whale activity budgets when vessels were nearby. Working with stakeholders, we translated these results into community-developed vessel operation guidelines and an informational brochure to help mitigate impacts on whales.

 

Hann, C., Stelle, L., Szabo, A. & Torres, L. (2018) Obstacles and Opportunities of Using a Mobile App for Marine Mammal Research. ISPRS International Journal of Geo-Information, 7, 169. http://www.mdpi.com/2220-9964/7/5/169

This study demonstrates the strengths (fast and cheap data collection) and weaknesses (spatially biased data) of marine mammal data collected using the mobile app Whale mAPP. We emphasize the need for increased citizen science participation to overcome obstacles, which will enable this data collection method to achieve its great potential.

 

Barlow, D.R., Torres, L.G., Hodge, K., Steel, D., Baker, C.S., Chandler, T.E., Bott, N., Constantine, R., Double, M.C., Gill, P.C., Glasgow, D., Hamner, R.M., Lilley, C., Ogle, M., Olson, P.A., Peters, C., Stockin, K.A., Tessaglia-Hymes, C.T. & Klinck, H. (in press) Documentation of a New Zealand blue whale population based on multiple lines of evidence. Endangered Species Research. https://doi.org/10.3354/esr00891.

This study used genetics, acoustics, and photo-id to document a new population of blue whales around New Zealand that is genetically isolated, has high year-round residence, and shows limited connectivity to other blue whale populations. This discovery has important implication for population management, especially in the South Taranaki Bight region of New Zealand where the whales forage among industrial activity.

 

Burnett, J.D., Lemos, L., Barlow, D.R., Wing, M.G., Chandler, T.E. & Torres, L.G. (in press) Estimating morphometric attributes of baleen whales with photogrammetry from small UAS: A case study with blue and gray whales. Marine Mammal Science.

Here we developed methods to measure whale body morphometrics using images captured via Unmanned Aerial Systems (UAS; ‘drones’). The paper presents three freely available analysis programs and a protocol to help the community standardize methods, assess and minimize error, and compare data between studies.

 

Holdman, A.K., Haxel, J.H., Klinck, H. & Torres, L.G. (in press) Acoustic monitoring reveals the times and tides of harbor porpoise distribution off central Oregon, USA. Marine Mammal Science.

Right off the Newport, Oregon harbor entrance we listened for harbor porpoises at two locations using hydrophones. We found that porpoise presence at the shallow rocky reef site corresponds with the ebb tidal phase, while harbor porpoise presence at the deeper site with sandy bottom was associated with night-time foraging. It appears that harbor porpoise change their spatial and temporal patterns of habitat use to increase their foraging efficiency.

 

Derville, S., Torres, L.G., Iovan, C. & Garrigue, C. (in press) Finding the right fit: Comparative cetacean distribution models using multiple data sources. Diversity and Distributions.

Species distribution models (SDM) are used widely to understand the drivers of cetacean distribution patterns, and to predict their space-use patterns too. Using humpback whale sighting datasets in New Caledonia, this study explores the performance of different SDM algorithms (GAM, BRT, MAXENT,  GLM, SVM) and methods of modeling presence-only data. We highlight the importance of controlling for model overfitting and thorough model validation.

 

Bishop, A.M., Brown, C., Rehberg, M., Torres, L.G. & Horning, M. (in press) Juvenile Steller sea lion (Eumetopias jubatus) utilization distributions in the Gulf of Alaska. Movement Ecology.

This study examines the distribution patterns of juvenile Steller sea lions in the Gulf of Alaska to gain a better understanding of the habitat needs of this vulnerable demographic group within a threatened population. Utilization distributions were derived for 84 tagged sea lions, which showed sex, seasonal and spatial differences. This information will support the development of a species recovery plan.

This comic seemed appropriate here. Thanks for everyone’s hard work!

Assessing suitable sea otter habitat along Oregon’s coast

By Dominique Kone, Masters Student in Marine Resource Management

When considering a species reintroduction into an area, it is important to assess the suitability of the area’s habitat before such efforts begin. By doing this assessment at the outset, managers and conservationists can gain a better understanding of the capacity of the area to support a viable population overtime, and ultimately the success of the reintroduction. However, to do a habitat assessment, researchers must first have a base understanding of the species’ ecological characteristics, behavior, and the physical habitat features necessary for the species’ survival. For my thesis, I plan to conduct a similar assessment to identify suitable sea otter habitat to inform a potential sea otter reintroduction to the Oregon coast.

Source: The Tribune.

To start my assessment, I conducted a literature review of studies that observed and recorded the various types of habitats where sea otters currently exist. In my research, I learned that sea otters use in a range of environments, each with a unique set of habitat characteristics. With so many features to sort through, I have focused on specific habitat features that are consistent across most of the current range of sea otters – from Alaska to California – and are important for at least some aspects of sea otters’ everyday life or behavior, specifically foraging. Focusing my analysis on foraging habitat makes sense as sea otters require around 30% of their body weight in food every day (Costa 1978, Reidman & Estes 1990). Meaning sea otters spend most of their day searching for food.

Here, I present four habitat features I will incorporate into my analysis and explain why these features are important for sea otter foraging behavior and survival.

Habitat Features:

  1. Kelp: Sea otters are famously known for the benefits they provide to kelp forests. In the classic three-trophic-level model, sea otters allow for the growth of kelp by keeping sea urchins – consumers of kelp – in check (Estes & Palmisano 1974). Additionally, sea otters and kelp have a mutually-beneficial relationship. Sea otters will often wrap themselves amongst the top of kelp stocks while feeding, resting, or grooming to prevent being carried away by surface currents. Meanwhile, it’s thought that kelp provide a refuge for sea otters seeking to avoid predators, such as sharks, as well as their prey.
Source: The Telegraph.
  1. Distance from Kelp: The use of kelp, by sea otters, is relatively straight-forward. Yet, kelp can still have an influence on sea otter behavior even when not used directly. A 2014 study found that sea otters along the southern California coast were almost 10 times more likely to be located within kelp habitat than outside, while outside kelp beds sea otter numbers declined with distance from the edge of kelp canopies. Sea otters will often forage outside or next to kelp canopies when prey’s available, and even sometimes to socialize in age- or sex-specific rafts (Lafferty & Tinker 2014). These findings indicate that sea otters can and do regularly disperse away from kelp habitat, but because they’re so dependent on kelp, they don’t stray very far.

 

  1. Seafloor Substrate: Sea otters forage over a variety of sediment substrates, including rocks, gravel, seagrass, and even sometimes sand. For example, sea otters hunt sea urchins over rocky substrates, while in other areas they may hunt for crabs in seagrass beds (Estes & Palmisano 1974, Hughes et al. 2014). The type of substrate sea otters forage in typically depends on the substrate needs of their target prey species. Despite some variability across their range, sea otters predominantly forage in rocky substrate environments. Rocky substrate is also necessary for kelp, whose holdfasts need to attach to hard, stable surfaces (Carney et al. 2005).
Source: Save our Seas Foundation.
  1. Depth: Seafloor depth plays a pivotal role in sea otter foraging behavior and therefore acts as a natural boundary that determines how far away from shore sea otters distribute. Many of the prey species sea otters eat – including sea urchins, crabs, and snails – live on the seafloor of the inner continental shelf, requiring sea otters to dive when foraging. Interestingly, sea otters exhibit a non-linear relationship with depth, where most individuals forage at intermediate depths as opposed to extremely shallow or deep waters. One study found the average foraging depth to be around 15 meters (Lafferty & Tinker 2014). This behavior results in a hump-shaped distribution of diving patterns as illustrated in Figure 1 below.
Figure 1. Average probability of occurrence as a function of depth for female (A) and male (B) sea otters as predicted by a synoptic model of space-use (Tinker et al. 2017).

Of course, local conditions and available habitat are always a factor. For example, a study found that sea otters along the coast of Washington foraged further from shore and in slightly shallower environments than sea otters in California (Laidre et al. 2009), indicating that local topography is important in determining distribution. Additionally, diving requires energy and limits how deep sea otters are able to forage for prey. Therefore, diving patterns are not only a function of local topography, but also availability of prey and foraging efficiency in exploiting that prey. Regardless, most sea otter populations follow this hump-shaped diving pattern.

Source: Doretta Smith.

These features are not a complete list of all habitat characteristics that support viable sea otter populations, but seem to be the most consistent throughout their entire range, as well as present in Oregon’s nearshore environment – making them ideal features to include in my analysis. Furthermore, other studies that have predicted suitable sea otter habitat (Tinker et al. 2017), estimated carrying capacity as a product of suitable habitat identification (Laidre et al. 2002), or simply observed sea otter foraging behavior (Estes & Palmisano 1974), have echoed the importance of these four habitat features to sea otter survival.

As with most reintroduction efforts, the process of identifying suitable habitat for the species of interest can be complicated. No two ecosystems or habitats are exactly alike and each comprise their own unique set of physical features and are impacted by environmental processes to varying degrees. The Oregon coast consists of a unique combination of oceanographic conditions and drivers that likely impact the degree and amount of available habitat to sea otters. Despite this, by focusing on the habitat features that are consistently preferred by sea otters across most of their range, I will be able to identify habitat most suitable for sea otter survival in Oregon. The questions of where this habitat is and how much is available are what I’ll determine soon, so stay tuned.

References:

Carney, L. T., Robert Waaland, J., Kilinger, T., and K. Ewing. 2005. Restoration of the bull kelp Nereocystis luetkeana in nearshore rocky habitats. Marine Ecology Progress Series. 302: 49-61.

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

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

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