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Reporting back on the Whales in a Changing Ocean Conference

Solène Derville, Entropie Lab, Institute of Research for Development, Nouméa, New Caledonia (Ph.D. student under the co-supervision of Dr. Leigh Torres)

My flight back to New Caledonia gives me time to think and process all that I have experienced in the last few days. From April 4^th to 6^th, I had the great opportunity to attend the “Whales in a Changing Ocean” conference held in Nuku’alofa, in the Kingdom of Tonga. This conference organized by SPREP (Secretariat of the Pacific Regional Environment Programme) as part of the “Protect Pacific Whales – Ocean Voyagers” campaign brought together members of the Pacific Island governments, whale-watching operators, NGOs, IGOS and scientists.

As a relatively novice PhD student studying humpback whale spatial ecology in New Caledonia this was my first experience attending a conservation and management focused conference. To be completely honest, when I was asked to attend the conference as part of the work I am conducting on the effect of environmental changes on humpbacks of the South Pacific breeding grounds, I gladly accepted the offer, as an opportunity for me to learn more about the political mechanisms underlying international conservation plans. However, I was a little sceptical as to what tangible outputs could come out of such event. How would the science be integrated into this rather political event? How many delegations would be able to make it? Would they manage to agree on strong objectives regarding the conservation of cetaceans in the region?

Leena Riekkola, a PhD student at University of Auckland, and I with traditional flower necklaces offered by the organizers

On the first day of the conference, we sat through several hours of formal opening ceremony and comments from the governmental delegations that had travelled to Tonga from all over the Pacific: Samoa, Papua New Guinea, Tuvalu, Niue, French Polynesia, New Zealand, Australia, the Cook Islands, Palau, Fiji and many others. These comments mainly consisted of a succession of (well deserved) acknowledgments to the Tongan government for hosting the event and the enumeration of the endless list of threats faced by cetaceans in the region. Despite the tedious nature of this inevitable display of etiquette, I was impressed by the sight of all these governmental and non-governmental delegations sitting around the same table to discuss the future of whales. I was surprised to hear a note of emotion in several of the speeches that day. I clearly had not realized how valuable whales are to the Pacific islanders. Valuable economically of course, as whale watching is one of the most important drivers of tourism to several of these islands, most of all to Tonga. But also importantly, whales and dolphins bear a strong cultural value to the people of the Pacific. Many of the attendees shared stories and legends about whales, and I quickly realized that these animals were indeed a “cultural heritage” that people were eager to protect and preserve.

The next two days of the conference were built around a series of plenaries and workshops surrounding 3 themes: sustainable whale-watching, scientific research and emerging threats. While I was initially a bit lost and did not quite understand where all of this was going, I progressively saw several recommendations and objectives emerging from the discussions. By the end of the conference, I realized how much had been accomplished in only three days and that these achievements were more than just words. Four main outcomes resulted from this conference:

The commitment to adopt and sign a Pacific Island Year of the Whale Declaration by 11 nations/territories of the region (out of 21), namely: Australia, the Cook Islands, Fiji, New Caledonia, New Zealand, Palau, Papua New Guinea, Samoa, Tonga, Tokelau and Tuvalu. Not all of the governmental representatives were able to sign but it is likely that some will join later.

The agreement to a voluntary commitment to “Protect, conserve and restore whale populations in the Pacific islands”, which will be presented at the UN Oceans conference in June 2017.

A technical and scientific input from international working groups to help establish the next SPREP Whale and Dolphin Action Plan for 2018-2023
Tonga’s announcement of a whale sanctuary in their waters.

Governmental representatives group photo after signing the Pacific Island Year of the Whale Declaration

Whether these declarations of intentions and recommendations will actually lead to tangible actions in the short term, I could not tell. But I am glad I got the opportunity to witness the very first regional conference on whales in the Pacific Islands, and the celebration of these beautiful creatures and their place in Pacific cultures.

Feed from the scientific network: the digital library of a millennial student

Solène Derville, Entropie Lab, Institute of Research for Development, Nouméa, New Caledonia (Ph.D. student under the co-supervision of Dr. Leigh Torres)

If you are a follower of our blog, you may have noticed that bioinformatics and statistics hold a very important role in the everyday life of the GEMM Lab. As good-old field observations remain essential to the study of animal behaviour and ecosystems, the ecology field has greatly benefited from advances in information technologies. In fact, data analysis is now a discipline in itself, as innovative solutions must continuously be developed to cope with the challenges of ever increasing dataset size and complexity.

Artist’s impression of a complex network. ©iStock.com/Vertigo3d

So how does a poor biology student find her/his way in this digital and mathematical world? Most ecology departments will provide classes to learn the basics of statistical modelling and data analysis, but there is only so much you can learn through formal education. In practice, we ultimately always run into a problem, an exception that we have never heard of, and we have to figure it out on our own. As my initial training was in fundamental biology, self-teaching of other disciplines (statistics and bioinformatics) has taken a lot of my time as a Master’s student and now as a PhD student. This has made me feel lonely and a bit lost at times when I run into challenges that always seemed too big for me. But in the end, there is nothing more rewarding then solving problems by yourself after long hours of mind-scrambling.

Oh, sorry, did I say by myself? Nothing could be more wrong and more true at the same time! Because the place where I find all the answers to my questions, is in fact born from the contribution of thousands of scientists, which, despite not actually knowing each other, all work together to develop innovative solutions to modern world scientific challenges. The internet scientific network has been my best colleague over these past years and here I would like to share my enthusiasm for some of its best features that have helped me in my research.

If you look at my Firefox toolbar you will find two types of websites: let’s call them the “practical” and the “reflectional”.

The practical websites:

These are the websites I consult if I have a specific and practical question. Many forums exist where people exchange their experiences solving a great variety of problems. But sometimes conversations get lost in never-ending exchanges of opinions, some of which are not always scientifically well-founded. On the contrary, the StackExchange platform launched in 2009 has a strict policy on how questions should be asked (as precise and focused as possible) and should be answered (in an objective, opinion-free way). This makes it a very powerful tool to find quick and practical solutions to your everyday problems. This platform includes 136 different websites, each dedicated to a different topic. In my field, I mostly use: CrossValidated for statistical issues (e.g., Why does including latitude and longitude in a GAM account for spatial autocorrelation?) and StackOverflow for programming (e.g., plotting pie graphs on map in ggplot).

The latter will usually provide you with codes in the programming language of your choice (R, python, java, sql, etc.). Interestingly, even with more queries regarding Python to StackOverflow in 2015, R was the fastest-growing language between 2013 and 2015 on this same platform. If you haven’t decided on the language you want to “speak” yet, check out this fun infographic. But always remember that these tools keep evolving…

Academia can also be useful for questions regarding publications. For instance: How to reference multiple authors of a chapter from a book [APA]? Why might a journal editor reject a submission, but suggest submission to a sister journal? Or, h ow to best kill a manuscript as a peer reviewer?

And finally, if you’ve always wondered, “W hy don’t we remove door handles and let doors open both ways (inwards, outwards)?”, you’ll be pleased to know that other out-of-the-box-thinking people are sharing their opinion on the web…

Coming back to serious matters, it is important to recognize that you need the right key-word to access this gold-mine of website knowledge and sharing. The accuracy of your search answer will only be proportional to the quality of your question. In R for instance, if you keep googling “table” instead of “dataframe”, “list” instead of “vector”, or “size” instead of “dimensions”, you will likely get quickly drowned in the google-limbo. One way to be more efficient at your search strategy is to make sure you know your basics. Most of the programming languages used in ecology (e.g., R, Python, Matlab) share a similar vocabulary and structure, but before you start to run all sorts of crazy statistical analysis it is important to know what types of objects you are working with and how you want to format them. In R, I have found Hadley Wickham’s book, Advanced R, particularly useful to understand what happens back-stage.

Another good reference in the spatial ecology field is ZevRoss “Technical Tidbits From Spatial Analysis & Data Science”. This website is a particularly up-to-date blog for data processing and visualization in R.

More generally, I regularly check R-bloggers or simply the Comprehensive R Archive Network. A note on the latter: I know it doesn’t look pretty and the reference manuals for R packages are rather intimidating but it is still the number one reference to check when encountering a problem with a given function. Some authors make a special effort to write more user-friendly tutorials to their packages. Check for those by looking at the CRAN page of a given package, in the “downloads” section, “vignettes” subsection (e.g., for the adehabitatLT package vignette).

The reflectional websites:

The web is also an amazing media to reflect on our scientific practices, learn about current ecological theories, and acquire general knowledge across disciplines. In the scientific network, many blogs and forums exist where scientists can converse and debate ideas without the pressure of publication requirements. As a student trying to find my way in the great world of statistical modelling, I find these discussions and blogposts most useful to put my methodological choices in perspective and progressively build myself an opinion (still rather vague I’ll admit). Some of my most recent findings are: Dynamic Ecology Multa novit vulpes and From the bottom of the heap, the musings of a geographer. I am sure each of you has your own “rock star of the web”, so please share your favorite sites with us in the comments below.

Science not longer needs to wait for publication to be shared between peers and with the general public. The web offers us a new space to communicate, not only on that small part of our work that led to positive results, but also our negative results, frustrations and failures, which can at times be as informative and useful to the scientific community than our successes. So, wherever you stand, tell us about your ideas, and tell us about the challenges you have encountered, where you failed and where you succeeded. Because, this is what ecology is all about. Sharing knowledge across borders and cultures to understand the planet we live on and together take better care of it.

Reflecting on the graduate school experience

By: Amanda Holdman, MS student, Geospatial Ecology and Marine Megafauna Lab & Oregon State Research Collective for Applied Acoustics, MMI

This Thanksgiving I had a little something extra to be thankful for; two and a half weeks ago I successfully defended my master’s thesis, “Spatio-temporal patterns and ecological drivers of harbor porpoise off the central Oregon Coast”. It’s a good thing too because I think it was starting to turn me into a harbor porpoise. The last month, I was solitary, constantly eating, and I think I was starting to sleep with one hemisphere of my brain, while the other kept working.

In the weeks leading up to the submission of my thesis, I daydreamed about my life on the ‘other side’. As a means of pushing myself over the final hurdle I envisioned what it would be like to be free of a thesis, to reclaim my weekends, and how relieved I would feel to hand over the culmination of two and a half years of work – and at last here I am: on the other side, well almost.

The first week after my defense was just about as busy as the weeks leading up to my defense. I spent my time filing paperwork and moving things, packing up my office and house to head back to my home state of Indiana for the holidays, and tying up loose ends in Newport. For the past couple of weeks, I have been finishing up revisions on my thesis and formatting my work for publication, all while starting to look for a new job. After defending my masters I found time to “actually breathe” – I’m still as busy as always but now with a more consistent sleep schedule. The shift from all-research-and-writing-all-the-time has given me time to reflect a bit on what I’ve gained from the graduate school experience and what I know I still want or need to learn from it. Graduate school has supplied me with a tool box of skills that I didn’t realize I was acquiring day to day. Now, however, looking back over the years I realize how much I’ve grown as both a scholar and a person and in more ways than just learning how to craft scientific tweets in less than 140 characters (this really does take some skill).

Perseverance and Diligence

One big thing I learned from graduate school was how to transition from “panic” to “problem solving”. There were endless days of back breaking work that I had nothing to show for and days when I succumbed to imposter syndrome. I learned to pick myself up and solve the problems at hand though and find a way to move forward, sometimes even scratching my original idea to move towards something that worked in the end. That’s life. Things go wrong, plans don’t work out and yet our ability to pick ourselves up and carry on is one of the best skills we have. In graduate school you learn to never give up.

Time Management

I now assume that anyone who has been to graduate school is essentially an expert at multi-tasking. Between running a field season, taking and teaching courses, submitting research proposals, and trying to balance a social life, I didn’t realize how much of a pro I became at juggling many things at once. In other words, gaining a fundamental skill for being a working scientist

Resourcefulness

Graduate school taught me how to find the information I need. Every day I had a moment where I didn’t know an answer. In the beginning, I thought all you had to do was ask, but sometimes the first person you ask doesn’t know the answer either. Over time, I learned to dig through the literature, ask an expert in the field, or my favorite “try several different things and see how they differ”. Once I learned the hard lesson that there isn’t always an easy way out, I had subconsciously created an order of operations to figure it out.

Collaboration (and giving back the help to others who struggle where you once did)

Not many jobs teach us to work with a bunch of different minded people, but grad school does! I learned to work as a team, with scientists within and outside my lab who had personalities different from mine. Graduate school taught me to collaborate as much as possible and, more importantly, help someone with less experience to figure out their coding problems, or help them get their research proposals or publications out. Offering advice or expertise for a certain skill or method when I was busy helped me develop my team-building skills and proved to myself that I had skills to share.

There are good moments within bad moments

When a bad moment presented itself, I learned to focus on the good and recognize the moments that things worked out because I didn’t give up. These included following a bad presentation with a strong one, sparking the interest of collaborators, receiving an award for a conference presentation, or just the simple self-satisfaction of getting an R code to work properly. There are a lot of good moments in grad school, and it became important for me to celebrate them when they happened, but also not to take them for granted because they don’t come as often as the bad ones.

Importance of a strong support system

Unlike a harbor porpoise – I am very social person. Some can get through graduate school without any social interaction or encouragement from others, but there was no way that would have worked for me. Everyone copes with bad moments in graduate school in different ways – so my friends and family were my life-raft, especially those living in Newport. Mental and physical health are important to maintain in graduate school and it was beneficial for me to form a community early to help me through the tough moments. Although friends and family cannot completely relate to your situation (unless maybe they are also a graduate student) they will hear you out, care, listen and pull you out of a slump. Accepting their support and help drastically improved my mental health.

Work smarter, not necessarily harder, and forge your own path

When I look back at my past 2.5 years of graduate school now, I realize how hard I did truly work. I worked nights, weekends and evenings on weekdays. But in my last few months, I became more competent as my productivity peaked. I learned how to multi-task and plan better – not just in school, but also in my daily life. Graduate programs force you to do unique research, as you can’t write a thesis by reproducing someone else’s work. You have to learn from what others have done and then get creative. Creating something original demands trust in yourself, and avoiding trying to compare yourself to others. Forging your own path can be uncomfortable, but necessary.

I am confident to say that graduate school overall made me a better scientist, and a better person. I value the training and education that I was fortunate enough to receive. It seems everyone starts graduate school with stars in their eyes, and then sometime in the middle we get weighed down by the failures and frustrations of graduate life, and we can fail to remember what brought us here in the first place: Intense curiosity, a desire to learn, and a chance to improve the world. These factors made me opt for this experience and in spite of all the hardships along the way, grad school gave me a set of life skills. So if you are contemplating graduate school, currently working toward a graduate degree, or in a transitional phase of job-seeking or career-changing, I suggest taking a minute to reflect on what you have already, or could gain, from graduate school.

My days as a current GEMM lab member are dwindling down as finish my edits, preparing publications, search for jobs, and rekindle my network – but I look forward to being a long distance cheerleader for the current and future members of the GEMM lab.

When I entered graduate school – one of my committee members told me I would go through the five stages of grief – and she was right – but the end reward was more than worth it.

“Being a graduate student is like becoming all of the Seven Dwarves. In the beginning, you’re Dopey and Bashful. In the middle, you are usually sick (Sneezy), tired (Sleepy), and irritable (Grumpy). But at the end, they call you Doc, and then you’re Happy.”

The seamounts are calling and I must go: a humpback’s landscape

Solène Derville, Entropie Lab, Institute of Research for Development, Nouméa, New Caledonia (Ph.D. student under the co-supervision of Dr. Leigh Torres)

The deep ocean is awe-inspiring: vast, mysterious, and complex… I can find many adjectives to describe it, yet the immensity of it prevents me from picturing it in my mind. Landscapes are easy to imagine because we see them all the time, but their hidden ocean counterparts of seascapes with several kilometer-high seamounts and abyssal trenches are hard to visualize.

When I started a PhD on the spatial ecology of humpback whales, a species typically known for its coastal distributions, I never imagined my research would lead me to seamounts. Lesson of the day: you never know where research will lead you… So here is how it happened.

About twenty years ago when my supervisor, Dr Claire Garrigue, started working on humpback whales in New Caledonia, she was told by fishermen that humpbacks were often observed in prime fishing locations, about 170 km south of the mainland. After a little more investigation into this claim, it was discovered that these fishing spots corresponded with two seafloor topographic features: the Antigonia seamount and Torch Bank (Fig. 1), These features rise from the seafloor to depths of 30 m and 60 m respectively and are surrounded by waters about 1500 m deep. This led Dr. Garrigue to implement an ARGOS-satellite tagging program to follow the movements of humpbacks leaving the South Lagoon (one of the main breeding area in New Caledonia, Fig. 1). Sure enough, most of the tagged whales (61%) visited the Antigonia seamount (Fig. 2; Garrigue et al. 2015)⁠.

Map of New Caledonia and our study areas: the South Lagoon and the Southern Seamounts. Light grey lines represent 200m isobaths. Land is shown in black and reefs in grey. — Figure 1: Map of New Caledonia and our study areas: the South Lagoon and the “Southern Seamounts”. Light grey lines represent 200m isobaths. Land is shown in black and reefs in grey.

Figure 2: ARGOS tracking of 34 humpback whales tagged between 2007 and 2012 in the South Lagoon. The Antigonia seamount and Torch Bank are completely covered by tracklines.

Seamounts are defined as “undersea mountains rising at least 100m from the ocean seafloor” (Staudigel et al. 2010). Most of them have a volcanic origin and the majority of them are located in the Pacific Ocean (Wessel 2001). But what is the link between these structures and marine life? The physical and biological mechanisms by which seamounts attract marine wildlife are diverse (for a review see: Pitcher et al. 2008)⁠. In a nutshell, topography of the ocean floor influences water circulation and isolated seabed features such as seamounts affect vertical mixing and create turbulences, consequently resulting in higher productivity.

For instance, have you ever heard of internal waves? Contrary to the surface waves people play in at the beach, internal waves propagate in three dimensions within the water column and can reach heights superior to a 100m! When these waves encounter steep topography, they break, similar to what a “normal” wave would do when reaching shore. This creates complex turbulence, which in turn may attract megafauna such as cetaceans (see com. by Hans van Haren).

The importance of seamounts for cetaceans is often referenced in the literature, however, few studies have tried to quantify this preference (one of which was recently published by our labmate Courtney Hann, see Hann et al. 2016 for details). So what importance do these seamounts serve for humpback whales in New Caledonia? Are they breeding grounds, do they serve as a navigation cue, a resting area, or even a foraging spot (the latter being the less likely hypothesis given that humpback whales have never been observed feeding in tropical waters)?

To answer this question, an expedition to Antigonia was organized in 2008 and about 40 groups of whales were observed in only 7 days! The density of this aggregation, the high occurrence of groups with calves and the consistent singing of males suggested that this area may be associated with breeding or calving behavior. Several other missions followed, confirming the importance of this offshore habitat for humpbacks.

Looking through all this data I was struck by two things: 1) whales were densely aggregated on top of these seamounts but were rarely found in the surrounding area (Fig. 3), and 2) other seamounts with similar characteristics are only a few kilometers from Antigonia, but seem to be rarely visited by tagged whales.

What is so special about these seamounts? Why would energetically depleted females with calves choose to aggregate in these off-shore, densely occupied and unsheltered waters?

Figure 3: 3D surface plot of the seabed in the Southern seamount area. Humpback whale groups observed in-situ during the boat-based surveys conducted between 2001 and 2011 are projected at the surface of the seabed: blue points represent groups without calf and white points represent groups with calf. Antigonia and Torch Bank have a clear flat-top shaped which classifies them in the “guyot” seamount type. Most whale groups aggregated on top of these guyots. — Figure 3: 3D surface plot of the seabed in the Southern Seamounts area. Humpback whale groups observed during the boat-based surveys (2001-2011) are projected at the surface of the seabed: blue points represent groups without calf and white points represent groups with calf. Antigonia and Torch Bank have a clear flat-top shaped and are called “guyots” seamounts. Most whale groups aggregated on top of these guyots. For 3D interactive plot: click here.

I will spend the next two months at the GEMM lab in Newport, OR, trying to answer these questions using ocean models developed by New Caledonian local research teams (at IRD and Ifremer). I will be comparing maps of local currents and topography of several seabed features located south of the New Caledonia main island. The oceanographic model used for this study will allow me to analyze a great number of environmental variables (temperature, salinity, vertical mixing, vorticity etc.) through the water column (one layer every 10m, from 0 to 500m deep) and at a very fine spatio-temporal scale (1km and 1day, even 1 hour at specific discrete locations) to better understand humpback whale habitat preferences.

Figure 4: Modeled Sea Surface Temperature for July 15th 2013 (model in progress, based on MARS3D, development by Romain Legendre). A temperature front occurs in the middle of the study area, along the Norfolk ridge. On this image, a cold eddy is forming right on top of the Antigonia seamount. — Figure 4: Modeled Sea Surface Temperature for July 15th 2013 (model in progress, based on MARS3D, development by Romain Le Gendre). A temperature front occurs in the middle of the study area, along the Norfolk ridge. On this image, a cold eddy is forming right on top of the Antigonia seamount.

Looking forward to uncovering the mysteries of seamounts and sharing the results in December!

Literature Cited

Garrigue C, Clapham PJ, Geyer Y, Kennedy AS, Zerbini AN (2015) Satellite tracking reveals novel migratory patterns and the importance of seamounts for endangered South Pacific Humpback Whales. R Soc Open Sci

Hann CH, Smith TD, Torres LG (2016) A sperm whale’s perspective: The importance of seasonality and seamount depth. Mar Mammal Sci:1–12

Pitcher TJ, Morato T, Hart PJ, Clark MR, Haggan N, Santos RS (2008) Seamounts: ecology, fisheries & conservation. Oxford, UK: Blackwell Publishing Ltd.

Wessel P (2001) Global distribution of seamounts inferred from gridded Geosat/ERS-1 altimetry. J Geophys Res 106:19431–19441

Staudigel H, Koppers AP, Lavelle JW, Pitcer TJ, Shank TM (2010) Defining the word ‘seamount’. Oceanography 23,20–21.

A few things I’ve learned while writing a thesis

By: Amanda Holdman, MS student, Geospatial Ecology and Marine Megafauna Lab & Oregon State Research Collective for Applied Acoustics, MMI

“Never use the passive where you can use the active.” I recently received this comment in a draft of my thesis. While this pertained to a particular edit, it has since become my motto for writing in general – to stay active in writing. I knew before beginning this process, from my peers, that it takes time to write a thesis or dissertation, and usually much longer than anticipated, resulting in late caffeinated hours. My roommates have recently moved out, making it a perfect opportunity to convert my home into a great evening office. I needed fewer distractions so I unplugged the TV and set up a desk with ideal conditions for writing. I’m in a race against time with my defense set for only a month away, and getting into good writing habits has helped me smooth out a lot of the writing stress, so I figured I could share those tips.

Write sooner

The writing process can be daunting due to its size and importance. In the beginning I tended to wait until I thought I had researched enough about the topic. But, I have now learned not to wait until all the data is in and the results are clear to start writing. Some researchers might argue that results are needed before one can put the proper spin on the introduction, but spin isn’t quite needed for a first draft. Most of the writing can be actually be done before all the data have arrived. For example, I didn’t need to know the results of my observations before writing the manuscript about them; the rationale for having done the research doesn’t change with the results, so a draft of the introduction can be written without knowing the results. The methodology also doesn’t depend on the results, nor does the analysis that will be performed on the data, so a good framework for the results section can be written before all of the statistical tests are run. And before I know it, I have almost a full draft, just with quite a few gaps.

Write Continually

Productivity begets productivity, so don’t stop writing. It keeps my mind working and my project moving. I try to write a little every day or set a goal word limit. (500 words a day is easily obtainable and you feel proud at the end of the day). Writing as frequently as possible for me has helped to reveal gaps in my knowledge or understanding. Vague and disoriented writing tends to reflect a vague and disorganized thought, leading me to dig through the literature for more clarity.

Figure out how you write and edit

Some people are better writers when they first put their thoughts on paper and plan to go back and fix awkward sentences, poor word choices, or illogical sentences later. My perfection has always plagued me, so I always edit as a write, with one goal only: to make sure I’ve expressed the idea in my head clearly on the page. I don’t move on until the sentence (or thought) makes sense with no ambiguity in the meaning. Clarity of thought is always the aim in writing a manuscript, yet it is very difficult to come back to a section of writing days or weeks later and sort out a mess of thought if I don’t clarify my writing while the thought is still fresh in your head. This means I am constantly re-reading and revising what I’ve written, but also hopefully means that when I submit something to my advisor or committee it only needs simple revisions, thereby saving time by getting as “close to right” as I could the first time around.

Develop a routine

It’s important to learn when and what makes us productive. For me, writing in several short bursts is more efficient than writing in a few, long extended periods. When I try to write for long hours, I notice my concentration diminishing around the hour mark, so I try to take frequent 15 minute breaks. For me, the most productive parts of the day are the beginning the end. It’s important to build momentum early, and have a routine for ending the day too. At the end of each day, I always leave myself something easy to get started with the next day, so I wake up knowing exactly where I am going to start.

Find a template

Usually, when we decide on a date and deadlines for the final draft of our thesis due, we’re so frantic and pressed for time trying to get all the content, that we forget about the time it takes to make a draft pretty. My last HUGE time-saving tip is to find a colleague who has recently turned in their thesis or dissertation and still has their final word document. You can save time by reusing their document as a template for margins, page number position and other formatting guidelines. Everything you’ve written can easily be pasted into a formatted template.

Keep your motivation near

Finally, always try to keep the end result in mind. Whether it be holding a beautifully bound version of your thesis or a first author publication, keeping motivated is important. Publishing is not a requirement for completing a thesis but it is an ultimate goal for me. I know I owe it to myself, the people who I have worked with along the way, those who have supported me in some way (e.g., my committee), and to the funders that have helped pay for the research. Plus, to have a competitive edge in the next job I apply for, and to get the most leverage possible from my masters training, it is important for me to finish strong with a publication or two. Visualizing the end result helps me to take action to finish my thesis and advance my career.

Now, I think it’s about time to stop writing about writing a thesis and get back to actually writing my thesis.

Recapping and Reflecting on the International Marine Conservation Conference!

By: Amanda Holdman, MS student, Geospatial Ecology and Marine Megafauna Lab & Oregon State Research Collective for Applied Acoustics, MMI

The GEMM Lab recently returned from the 4^th International Marine Conservation Congress (IMMC4) in St. John’s, Newfoundland, Canada, and it was a whirlwind of activity to say the least. The flights were long and the morning coffee was scarce, but the setting was beautiful and plenty of scientific fun was had! The IMCC conferences are the largest international academic conferences on marine conservation and the theme of this year’s conference was to “Make Science Matter”, or in my interpretation “to use conservation science to drive policy change and implementation”. Over five days we were exposed to a flood of new ideas, hypothesis, methods/techniques, analyses and findings – even presenting our own!

Leigh, Florence, and I were all slated to give a talk on the opening day of presentations. Leigh presented on her new method for analyzing animal movement data in space and time, Florence on the effects of vessel activities on gray whales, and myself on the habitat use of harbor porpoise off of the Oregon Coast.

The conference was filled with non-stop talks, lunch sessions that incorporated workshops, student activities with plenary speakers, and an evening activity planned for every night. Short breaks during the conference shenanigans allowed for some exploring of the St. John’s area including Signal Hill, Cape Spear, and the George Street Festival. Highlights included humpback mom and calf, fin whales (my first time seeing them), dozens of seabirds I wish I could identify and some popular Canadian music.

View from Signal Hill, where the first transatlantic wireless signal was received in 1901.

The Arkells playing at the George St. Festival.

Light house at Cape Spear – the Eastern most point of North America!

The conference was an awesome place to learn, meet and network with new friends, and catch up with some familiar faces. For Florence and I, our research fit perfectly into the theme of the IMCC conference. Being able to translate results of our work into relevant actions that can lead to improved marine conservation was an amazing feeling. Entering the academic sphere for the first time can be daunting, but the IMCC community was friendly, open and dedicated. Having others outside of our OSU family take an interest in our research truly shows that all of our hard work has paid off. We received great feedback and even some suggestions we could incorporate into our manuscript submissions! Definitely not something to be taken for granted!

On a more personal note, my talk, “The spatio-temporal distribution and ecological drivers of harbor porpoise off of the Oregon coast” seemed to be well received, I was honored to be awarded runner up for best student presentation by the conference!

I would not have received this award if it was not for Leigh, my committee members, OSU, and my lab mates. I couldn’t have been more proud of our lab and the feedback that we received at IMCC.

But now, the stress is over, the audience is gone, I’m still riding my high but I’ve found a moment of quietness on the plane ride home to analyze myself. I’ve been to a few regional conferences, and have been lucky enough to attend two large international conferences. However, now that I am nearing the end of graduate school (23 months down, 4 to go), it thus seems like a sensible time to reflect on how to make the most of these trips and experiences.

Apart from managing our research projects and scientific writing in graduate school, we are faced with the big challenge of presenting our research to a range of audiences. Oral presentations are one of the most important ways in which we communicate scientific results to other scientists and to be honest, NOTHING paralyses me more than having to present my work – or so I thought.

I am no stranger to sweaty palms and a racing heart. Whether it’s 5 people, 50 people, or 500 people – public speaking has always been a gut wrenching experience for me. When it comes to presentations, my flight response is in full swing, and the only thing that keeps me from running away from the presentation is that I would be more embarrassed fleeing than just giving the presentation.

However, gradual exposure and better practice over the past couple of years has helped me get over my fear of public speaking. I can’t say that I never get nervous when I have to speak in front of other people, but now my fear is controllable. Now, when I feel myself starting to get anxious I remember that while these feelings are very much real, they do not mean that I cannot give a good talk. The trick for me was learning to be separate from my anxiety by acknowledging it and allowing myself to have that feeling, and then deciding that even with that feeling I can move forward. It took quite a bit of practice for me not to be overwhelmed by these feelings of anxiety – but I’m happy to report that presenting in large groups DOES get easier with practice!

So for me, speaking at IMCC granted me with a sense of confidence, perhaps even a career-changing affirmative opportunity. Scouting out your audience or the room you speak in advance, writing your talk well before the delivery date, and practicing it numerous times reduces an enormous amount of pre-presentation jitters. I’ve learned how to manage the jitters in order to give a good presentation. In fact, I think public speaking can even be fun in addition to being a great way to spread your message!

Doing a masters (Or PhD) means you constantly challenge yourself and improve your skills. As I continue to encounter new situations and tackle new challenges, I expect that I will go through more cycles of lag and growth as I did with public speaking. I hope that I will have the perspective and patience to appreciate the lag times as integral parts of my development. The IMCC conference was only a snapshot of a major high, but it was an important milestone of my scientific career and personal journey.

Here’s a few more pictures from the beautiful St. Johns! Jelly bean row!

Eating lunch and overlooking the harbor at Signal Hill.

Boat houses at Quidi Vidi Harbour.

SeaBASS 2016

By Samara Haver, MSc student, OSU Fisheries and Wildlife, ORCAA Lab

As a graduate student in bioacoustics (the study of noise produced by biological sources), my education is interdisciplinary. Bioacoustics is a relatively small field, and (together with my peers) I am challenged to find my way through coursework in ecology, physiology, physics, oceanography, statistics, and engineering to learn the background information that I need to develop and answer research questions (since this is my first post for the GEMM lab, here is a little more information about my interests). While this challenge (for all young bioacousticians) presents itself a little differently at all universities, the information gap is essentially the same. Hence, just over 6 years ago, Dr. Jennifer Missis-Old and Dr. Susan Parks recognized a need to fill this gap for graduate students in bioacoustics and created SeaBASS, a BioAcoustics Summer School.

This year, for the 4th iteration of the week-long program, I was lucky to have the opportunity to attend SeaBASS. I first heard about SeaBASS as a research assistant in Dr. Sofie Van Parijs’s passive acoustics group at the Northeast Fisheries Science Center, but the workshop is limited to graduate students only so I had to wait until I was officially enrolled in grad school to apply. My ORCAA lab-mates, Niki, Selene, and Michelle are all alumni of SeaBASS (read Miche’s re-cap from 2014 here ) so by the time I was preparing for my trip to upstate NY this summer to attend, I had a pretty good idea of what was to come.

As expected, the week was packed. I flew to the East Coast a few days early to visit our fearless ORCAA leader, Holger, at the Bioacoustics Research Program at the Cornell Lab of Ornithology, so I was lucky to be somewhat adjusted to EST by the time I arrived at Syracuse on Sunday afternoon. After exploring the campus, it was time for official SeaBASS programming to begin. Our first class, an “Introduction to Acoustics and Proportion”, began early on Monday morning. In the afternoon and through the rest of the week we also learned about active acoustics (creating a sound in the water and using the echo to detect animals or other things) and marine mammal physiology, echolocation, communication, and behavior. We also heard about passive acoustics (listening to existing underwater sounds), including the different types of technology being used and its application for population density estimation. On Friday afternoon, the final lecture covered the effects of noise on marine mammals.

Some SeaBASS-ers testing the hypothesis that humans are capable of echolocation.

In addition to the class lectures given by each instructor, we also heard individual opinions about “hot topics” in bioacoustics. This session was my favorite part of the week because we (the students) had the opportunity to hear from a number of accomplished scientists about what they believe are the most pressing issues in the field. Unlike a conference or seminar, these short talks introduced (or reinforced) ideas from researchers in an informal setting, and among our small group it was easy to hear impressions from other SeaBASS-ers afterwards. As a student I spend a lot of my time working alone; my ORCAA labmates are focused on related acoustic projects, but we do not overlap completely. The best part of SeaBASS was sharing ideas, experiences, and general camaraderie with other students that are tackling questions very similar to my own.

SeaBASS 2016

Although a full week of class would be plenty to take in by itself, our evenings were also filled with activities. We (students) shared posters (this was mine ) about our individual research projects, listened to advice about life as a researcher in the field, attended a Syracuse Chiefs baseball game, and at the end of each day reflected on our new knowledge and experiences over pints. So, needless to say, I returned home to Oregon completely exhausted, but also with refreshed excitement about my place in the small world of bioacoustics research.

Luckily we had beautiful weather for the baseball game!

Sonic Sea asks “can we turn down the volume before it’s too late?”

By: Amanda Holdman, MS student, Geospatial Ecology and Marine Megafauna Lab & Oregon State Research Collective for Applied Acoustics, MMI

It was March 15^th, 2000; Kenneth Balcomb was drinking coffee with his new summer interns in the Bahamas when a goose-beaked whale stranded on a nearby beach. Balcomb, a whale researcher and former U.S. Navy Officer, gently pushed the whale out to sea but the beaked whale kept returning to the shore. He continued this process until a second beaked whale stranding was reported further down the beach; and then a third. Within hours, 17 cetaceans had stranded in the Bahamas trying to escape ‘something’ in the water, and Kenneth Balcomb was determined to solve the mystery of the mass stranding. The cause, he eventually learned, was extreme noise – sonar tests from Navy Warships.

The world is buzzing with the sounds of Earth’s creatures as they are living, interacting, and communicating with one another, even in the darkest depths of the oceans. Beneath the surface of our oceans lies a finely balanced, living world of sound. To whales, dolphins and other marine life, sound is survival; the key to how they navigate, find mates, hunt for food, communicate over vast distances and protect themselves against predators in waters dark and deep. Yet, this symphony of life is being disrupted and sadly destroyed, by today’s increasing noise pollution (Figure 1). Human activities in the ocean have exploded over the past 5 decades with ocean noise rising by 3db per decade (Halpern et al. 2008). People have been introducing more and more noise into the ocean from shipping, seismic surveys for oil and gas, naval sonar testing, renewable energy construction, and other activities. This increased noise has significant impacts on acoustically active and sensitive marine mammals. However, as the Discovery Chanel’s new documentary Sonic Sea points out “The biggest thing about noise in the ocean is that humans aren’t aware of the sound at all.” The increase of ocean noise has transformed the delicate ocean habitat, and has challenged the ability of whales and other marine life to prosper and survive.

Figure 1: Anthropogenic sources contributing to ocean soundscapes and the impacts on marine megafauna survival (sspa.se)

Like the transformative documentary from 10 years ago, An Inconvenient Truth, which highlighted the reality and dangers of climate change, Sonic Sea aims to inform audiences of increased man-made noise in the oceans and the harm it poses to marine animals. The Hatfield Marine Science Center and Oregon Chapter of the American Cetacean Society offered a free, premier showing of the award-winning documentary followed by a scientific panel discussion. The panel featured Dave Mellinger, Joe Haxel, and Michelle Fournet of Oregon State University’s Cooperative Institute for Marine Resources Studies (CIMRS) marine bioacoustics research along with GEMM Lab leader, Leigh Torres, of the Marine Mammal Institute.

Sonic Sea introduces us to this global problem of ocean noise and offers up solutions for change. The film uncovers how better ship design, speed limits for large ships, quieter methods for under water resource exploration, and exclusion zones for sonar training can work to reduce the noise in our oceans. However, these efforts require continued innovation and regulatory involvement to bring plans to action.

Around the world the scientific community, policymakers and authorities such as The National Oceanic and Atmospheric Administration (NOAA), the European Union (EU), the International Maritime Organization (IMO) and other authorities have increasingly pressed for the reduction of noise. NOAA, which manages and protects marine life in United States waters, is trying to reduce ocean noise through their newly released Ocean Noise Strategy Roadmap, where the challenge is dealt with as a comprehensive issue rather than a case-by-case basis. This undersea map is a 10-year plan that aims to identify areas of specific importance for cetaceans and the temporal, spatial, and frequency of man-made underwater noise. After obtaining a more comprehensive scientific understanding of the distributions and effects of noise in the ocean, these maps can help to develop better tools and strategies for the management and mitigation of ocean noise.

Sonic Sea states “we must protect what we love” but then asks “how we can love it if we don’t understand it?” Here at GEMM Lab and the Marine Mammal Institute, we are trying to understand marine species ecology, distributions and behavioral responses to anthropogenic impacts. One of the suggestions Sonic Sea makes to reduce the impact of ocean noise is to restrict activity in biologically sensitive habitats. Therefore, we must know where these important areas are. In an ideal world, we would have a good inventory of data on the marine animals present in a region and when these animals breed, birth and feed. Then we could use this information to guide marine spatial planning and management to keep noise out of important habitats. My thesis project aims to provide such baseline information on harbor porpoise distribution patterns within a proposed marine energy development site. By filling knowledge gaps about where marine animals can be found and why certain habitats are critical, conservation efforts can be more directed and effective in reducing threats, such as ocean noise, to marine mammals.

Noise in our oceans is hard to observe, but its effects are visibly traumatic and well-documented. Unlike other sources of pollution to our oceans, (climate change, acidification, plastic pollution), which may take years, decades or centuries to dissipate, reducing ocean noise is rather straight forward. “Like a summer night when the fireworks end, our oceans can quickly return to their natural soundscape.” Ocean noise is a problem we can fix. To quiet the world’s waters, we all need to raise our voices so policy makers hear of this problem. That’s what Sonic Sea is all about: increasing awareness of this growing threat and building a worldwide community of citizen advocates to help us turn down the volume on undersea noise. If we sit back and do nothing to mitigate oceanic noise pollution, the problem will likely worsen. I highly suggest watching Sonic Sea. Then, together, we can speak up to turn down the noise that threatens our oceans — and threatens us all.

Sonic Sea airs TONIGHT (6/8) for World Ocean’s Day on Animal Planet at 10pm ET/PT!

An update on Oregon’s sound sensitive marine mammal, the harbor porpoise.

By Amanda Holdman, M.S. Student

Marine renewable energy is developing at great speeds all around the world. In 2013, the Northwest Marine Renewable Energy Center (NMREC) chose Newport, Oregon as the future site of first utility-scale, grid-connected wave energy test site in the United States – The Pacific Marine Energy Center (PMEC). The development of marine energy holds great potential to help meet our energy needs – it is renewable, and it is predicted that marine energy sources could fulfill nearly one-third of the United States energy demands.

Wave energy construction in Newport could begin as early as 2017. Therefore, it is important to fully understand the potential risks and benefits of wave energy as the industry moves forward. Currently, there is limited information on wave energy devices and the potential ecological impacts that they may have on marine mammals and their habitats. In order to assess the effects of wave energy, pertinent information needs to be collected prior to the installation of the devices.

This is where I contribute to the wave energy industry in Oregon.

Harbor porpoise are a focal species when it comes to renewable energy management; they are sensitive to a range of anthropogenic sounds at very low levels of exposure and may show behavioral responses before other marine mammals, making them a great indicator species for potential problems with wave energy. Little is known about harbor porpoise in Oregon, necessitating the need to look at the fine scale habitat use patterns of harbor porpoise within the proposed wave energy sites.

I used two methods to study harbor porpoise presence and activity in coastal waters: visual boat surveys, and passive acoustic monitoring. Visual surveys have a high spatial resolution and a low temporal resolution, meaning you can conduct visual boat surveys over a wide area, but only during daylight hours. Whereas acoustic surveys have opposite characteristics; you can conduct surveys during all hours of the day, however, the range of the acoustic device is only a few hundred meters. Therefore, these methods work well together to gain complimentary information about harbor porpoise. These methods are crucial for collecting baseline data on harbor porpoise distribution, and providing valuable information for understanding, managing, and mitigating potential impacts.

Bi-monthly standard visual line-transect surveys were conducted for two full years (October 2013-2015), while acoustic devices were deployed May – October 2014. Field work ended last October, and since then, data analysis efforts have uncovered seasonal, diel, and tidal patterns in harbor porpoise occurrence and activity.

Harbor porpoises in Oregon are thought to be seasonally migratory. With the onset of spring, coinciding with the start of the upwelling season, porpoise are thought to move inshore and abundance increases into the summer. Most births also occur during the late spring and summer. With the return of winter, porpoise are thought to leave the coastal waters and head out to the deeper waters (Dohl 1983, Barlow 1988, Green et al. 1992).

Results from my data support this seasonal trend. Both visual survey and acoustic recording data document the general pattern of peak porpoise presence occurring in the summer months of June and July, with a gradual decline of detections into the fall (Fig. 1 & 2).

Figure 1: Overall, from our acoustic surveys we see a large increase from May to June, suggesting the arrival of harbor porpoise to coastal waters. From July, we see a slow decline into the fall months, suggestive of harbor porpoise moving offshore.

Figure 2: Our data from visual surveys mimic those of our acoustic surveys. We see a large increase of porpoises from May to June and then a decline into the fall. We had very low survey effort in July, due to rough seas. If we were able to survey more, it is likely we would have seen more harbor porpoise during this time.

Using acoustic recorders, we are able to get data on harbor porpoise occurrence throughout all hours of the day, regardless of weather conditions. We deployed hydrophones in two locations – one in a near-shore REEF habitat located 4 km from shore, and the second in the middle of the South Energy Testing Site (SETS) 12 km off-shore. These two sites differ in depth and habitat type. The REEF habitat is 30 m deep and has a rocky bottom as a habitat type, while SETS is 60 m deep and has a sandy bottom. When we compare the two sites (Figure 3), we can see that harbor porpoise have a preference for the REEF site.

Additionally, we are also able to get some indices of behavior from acoustic recordings. Equivalent to sonar or radar, marine mammals use echolocation (high frequency sounds) to communicate and navigate. Marine mammals, specifically odonotocetes, also use echolocation to locate prey at depth when there is very little or no light. Porpoises use a series of clicks during their dives, and as the porpoise approach their prey, the clicks become closer and closer together so they sound like a continuous buzz. When studying echolocation patterns in odontocetes we typically look at the inter-click-intervals (ICIs) or the time between clicks. When ICIs are very close together (less than 10 ms apart) it is considered a foraging behavior or a buzz. Anything greater than 10 ms is classified as other (or clicks in this figure).

Figure 3: We see harbor porpoise clicks were detected about 27% of the time at the REEF, but only 18% at SETS. Potential feeding was also higher at the REEF site (14%) compared to (4%) at SETS.

Not only did we find patterns in foraging behavior between the two sites, we also found foraging patterns across diel cycles and tidal cycles:

We found a tendency for harbor porpoise to forage more at night (Figure 4).
The diel pattern of harbor porpoise foraging is stronger at the SETS than the REEF site (Figure 4). This result may be due to the prey at the SETS (sandy bottom) exhibiting vertical migration with the day and night cycles since prey there do not have alternative cover, as they would in the rocky reef habitat.
At the reef site, we see a relationship between increased foraging behavior and low tide (Figure 5).

Figure 4: When analyzing data for trends in foraging behavior across different sites and diel cycles, we use a ratio of buzzes to clicks, so that we incorporate both echolocation behaviors in one value. This figure shows us that the ratio of buzzes to clicks is pretty similar at the REEF site across diel periods, but there is more variation at the SETS site, with more detections at night and during sunrise.

Figure 5: Due to the circular nature of tides rotating between high tide and low tide, circular histograms help to observe patterns. In this figure, we see a large preference for harbor porpoise to feed during low tide. We are unclear why harbor porpoise may prefer low tide, but the relationship may be due to minimal current movement that could enhance feeding opportunities for porpoises.

Overall, the combination of visual surveys and passive acoustic monitoring has provided high quality baseline data on harbor porpoise occurrence patterns. It is results like these that can help with decisions regarding wave energy siting, operation and permitting off of the Oregon Coast.

REFERENCES

Barlow, J. 1987. Abundance estimation for harbor porpoise (Phocoena phocoena) based on ship surveys along the coasts of California, Oregon and Washington. SWFC Administrative Report LJ-87-05. Southwest Fishery Center, La Jolla, CA. 36pp.

Dohl, T.P., Guess, R.C., Dunman, M.L. and Helm, R.C. 1983, Cetaceans of central and northern California, 1980-83: status, abundance, and distribution. Final Report to the Minerals Management Service, Contract 14-12-0001-29090. 285pp.

Green, G.A., Brueggeman, J. J., Grotefendt, R.A., Bowlby, C.E., Bonnel, M. L. and Balcomb, K.C. 1992. Cetacean distribution and abundance off Oregon and Washington, 1989-1990. Chapter 1 In Oregon and Washington Marine Mammal and Seabird Surveys. Ed. By J. J. Brueggeman. Minerals Management Service Contract Report 14-12-0001-30426.

A porpoise-full lesson on cetacean identification

By Amanda Holdman, M.S. student

The rain is beginning to lighten, the heavy winds are starting to dissipate, and the sun is beginning to shine. Seabirds are starting to fill the air and marine mammals are starting to fill the coastline, making this week a perfect time to learn about some of the small, cryptic cetaceans that consider the Oregon coast home year round.

While I was walking my dog on South Beach in Newport last week, I heard the mother of a small family point and shout that she had just seen an animal that she referred to as a “porpoise/dolphin/small whale.” Upon a second sighting of it, she ruled against the small whale and decided on a dolphin. In reality, she had just sighted a harbor porpoise.

Throughout the duration of my work with Oregon State studying the patterns of harbor porpoise occurrence, one of the most frequently asked questions I get is “What is the difference between a porpoise and a dolphin?”

Differentiating between a dolphin and porpoise is probably the most common identification mistake when it comes to cetaceans. Understandably, there is significant confusion between the two species. The words dolphin and porpoise were, colloquially, used as synonyms until the 1970’s. Unlike lions and tigers that are not only in the same family, but also the same genus, dolphins and porpoises are in different families, having diverged evolutionarily about 15 million years ago! Therefore, dolphins and porpoises are more distinct than lions and tigers. These differences span from head and fin shape, to behavior, group size and vocals.

Physical Differences

Most people are quite certain they are seeing a dolphin mainly because dolphins are more prevalent than porpoises; over 30 species of dolphins are known to exist, but only 6 porpoise species have been identified worldwide. Unless, you’ve seen dolphins and porpoises side by side, nose to fin, it is quite difficult to tell the difference at first glance. In the natural history of cetacean’s course at Oregon State, we are taught that the three main visual differences are in the shape of the teeth, snout, and dorsal fin. But in reality, the first two characteristics aren’t likely to help you spot them from shore. In addition to fin size, the behavior and group size is more likely to cue you in on what animal you are seeing. The picture below does a pretty good job summarizing their physical characteristics. Porpoise have a small triangle fin, while dolphins have more of a curved, pointy fin.

Drawing by Mike Rock, 2009.

Size Differences

The lengths and widths of dolphins vary anywhere from 4 feet to 30 feet. Killer whales, the largest dolphin species and known predator to the harbor porpoise, can weigh up to ten tons, while the harbor porpoise is about five feet and rarely weighs in over 150 pounds. Porpoises are one of the smallest cetaceans, and because of their small size, they lose body heat to the water more quickly than other cetaceans. Their blunt snout is likely an adaptation to minimize surface area to conserve heat. The small sizes of porpoise require them to eat frequently, rather than depending on fat reserves, making them more of an opportunistic feeder. The need to constantly forage also keeps harbor porpoise from migrating on a large scale. Harbor porpoise are known to move from onshore to offshore waters with changing water temperatures and prey distributions, but not known to make long migration trips.

Social Differences

Porpoises are also less social and talkative than dolphins. Dolphins are typically found in large groups, can be highly acrobatic, and often seen bow-riding. Porpoise, specifically harbor porpoise, are often found singularly or in groups of two to three, and shy away from vessels, making them difficult to observe at sea. While both species have large melon heads for echolocation purposes, dolphins make whistles through there blow holes to communicate with each other underwater. Evolutionary scientists believe porpoises do not whistle due to structural differences in their blowhole. (This is why acoustics is such a great way to learn about the occurrence patterns of harbor porpoise – their echolocation is very distinct!) Porpoise echolocation signals have evolved into a very narrow frequency range – theoretically to protect themselves from killer whale predation by echolocating at a frequency killer whales cannot hear. Dolphins have evolved other strategies to avoid predators such as large group size and fast speed.

While differentiating between porpoises and dolphins takes a bit of practice, it is important to differentiate between the two species because we manage them differently due to some of their morphological differences. Their different adaptations between the species make them more sensitive to certain stressors. For example, for harbor porpoise, the sound produced from boat noise or renewable energy devices is more likely to impact them than other cetaceans. The sensitivity of the nerve cells in the ears of animals (including humans) generally corresponds to the frequencies that each animal produces. So animals like the harbor porpoise have more nerves in their ears that are tuned to very high frequencies (since they make high frequency sounds). If the nerve cells in the harbor porpoise ears become damaged, their ability to communicate, navigate and find food is seriously affected. In addition to their small home ranges and moderately high position in the food web, the sensitivity of harbor porpoise to ocean noise levels make harbor porpoise an important indicator species for ecosystem health, and an important species to study on the Oregon Coast.

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