Fishing with dolphins

By Leila Lemos, Ph.D. Student, Department of Fisheries and Wildlife, OSU

Hello everybody! I am Leila Lemos, a new member of the GEMM Lab. I am from Rio de Janeiro, Brazil, and moved to Corvallis just 2 months ago where I am now taking classes at OSU. Although I have not yet travelled around Oregon to see my surroundings I am loving the fall colors! We don’t have all of this yellow/orange/red in our Brazilian trees; it’s amazing! The green of the pines also enchanted me. What a beautiful place! However, I confess that I do miss being close to the ocean, so I am looking forward to being based in Newport next year. So, since I cannot see the ocean for now, let’s talk a bit about it and the dynamic cetaceans that live there.

My thesis will explore the impact of ocean noise on the physiology of gray whales, but I have not started my fieldwork yet. So for my first blog post I will discuss a unique interaction between bottlenose dolphins (Tursiops truncatus) and fisherman that occurs in the cities of Laguna, in the state of Santa Catarina, and Tramandaí and Imbé, in the state of Rio Grande so Sul, in southern Brazil. Unlike most relationships between fishermen and marine mammals, this interaction is mutually beneficial and both species appear to seek each other out. There are only three other places in the world where a similar interaction occurs: Mauritania, in the west coast of Africa; Myanmar, in the south coast of Asia; and in the east coast of Australia.

In the southern Brazil, dolphins and artisanal mullet fishermen have adapted their hunting strategies to perform a cooperative foraging strategy. Cast net fisherman wait for the dolphins to arrive and then observe their behavior. Only when a specific aggressive behavior pattern is observed do the fishermen enter the water with their nets. The dolphins move closer to the fishermen and begin rolling movements that trap fish close to the margin. The fishermen wait to throw their cast nets into the water until the dolphins perform specific and vigorous behaviors described by Simões-Lopes et al. (1998):

  • the dolphin shows an arched back;
  • the dolphin exposes its head and hits the surface with the throat;
  • the dolphin moves rapidly, showing just the dorsal fin, producing a whirl;
  • the dolphin slaps its tail against the surface.

 

Fishermen waiting for a signal to throw the cast net in Laguna, Santa Catarina, Brazil. Source: Diário Catarinense, 2013.
Fishermen waiting for a signal to throw the cast net in Laguna, Santa Catarina, Brazil. Source: Notícias UFSC, 2009.
Another shots of fishermen waiting to throw the cast net in Laguna, Santa Catarina, Brazil. Source: Notícias UFSC, 2009.

 

This partnership is mutually beneficial. Dolphins use the disturbance caused by the net to separate the mullet school and trap individual prey. This method allows the dolphins to reduce escapees, capture more prey, and ultimately increase their net energy gain.

For fishermen, this cooperative association leads to greatly increased captures of mullet. The water in the southern coast of Brazil is too murky for the fishermen to see the schools and therefore know where to throw their net. By watching the behavior of the dolphins, the fisherman is able to throw his net at the exact time and location of the passing mullet shoal.

While this symbiotic relationship is remarkable, it is also hereditary in both humans and dolphins. The calves follow their mothers during the foraging events and learn the movements used in this cooperative behavior. Likewise, the fishermen learn their techniques from their relatives through observation. This cross-species interaction has created cultural ties of great socioeconomic value for both humans and dolphins. Furthermore, this unique relationship demonstrates how clever and adaptive both taxa are when it comes to capturing prey. Wouldn’t it be great if more teamwork like this were possible?

 

Here is a video that captures this amazing relationship:

Until next time and thanks for reading!

 

 

Bibliographic References:

Diário Catarinense, 2013. Interação entre golfinhos e pescadores em Laguna chama a atenção de produtores da BBC. Retrieved from http://diariocatarinense.clicrbs.com.br/sc/geral/noticia/2013/05/interacao-entre-golfinhos-e-pescadores-em-laguna-chama-a-atencao-de-produtores-da-bbc-4151948.html

Notícias UFSC, 2009. Especial pesquisa: UFSC estuda pesca cooperativa entre golfinhos e pescadores em Laguna. Retrieved from http://noticias.ufsc.br/2009/08/especial-pesquisa-ufsc-estuda-pesca-cooperativa-entre-golfinhos-e-pescadores-em-laguna/

Simões-Lopes, P.C., Fabián, M.E., Menegheti, J.O., 1998. Dolphin Interactions with the mullet artisanal fishing on southern Brazil: a qualitative and quantitative approach. Revta bras. Zool. 15(3), 709-726.

 

 

On learning to Code…

By Amanda Holdman, MSc student, Dept. Fisheries and Wildlife, OSU

I’ve never sworn so much in my life. I stared at a computer screen for hours trying to fix a bug in my script. The cause of the error escaped me, pushing me into a cycle of tension, self-loathing, and keyboard smashing.

The cause of the error? A typo in the filename.

When I finally fixed the error in my filename and my code ran perfectly – my mood quickly changed. I felt invincible; like I had just won the World Cup. I did a quick victory dance in my kitchen and high-fived my roommate, and then sat down and moved on the next task that needed to be conquered with code. Just like that, programming has quickly become a drug that makes me come back for more despite the initial pain I endure.

I had never opened a computer programming software until my first year of graduate school. Before then Matlab was just the subject of a muttered complaint by my college engineering roommate. As a biology major, I blew it off as something (thank goodness!) I would never need to use. Needless to say, that set me up for a rude awakening just one year later.

The time has finally come for me to, *gulp*, learn how to code. I honestly think I went through all 5 stages of grief before I realized I was at the point where I could no longer put it off.

By now you are familiar with the GEMM Lab updating you with photos of our charismatic study species in our beautiful study areas. However, summer is over. My field work is complete, and I’m enrolled in my last course of my master’s career. So what does this mean? Winter. And with winter comes data analysis. So, instead of spending my days out on a boat in calm seas, watching humpbacks breach, or tagging along with Florence to watch gray whales forage along the Oregon coast, I’ve reached the point of my graduate career that we don’t often tell you about: Figuring out what story our data is telling us. This stage requires lots of coffee and patience.

However, in just two short weeks of learning how to code, I feel like I’ve climbed mountains. I tackle task after task, each allowing me to learn new things, revise old knowledge, and make it just a little bit closer to my goals. One of the most striking things about learning how to code is that it teaches you how to problem solve. It forces you to think in a strategic and conceptual way, and to be honest, I think I like it.

For example, this week I mapped the percent of my harbor porpoise detections over tidal cycles. One of the most important factors explaining the distribution and behavior of coastal marine mammals are tides. Tidal forces drive a number of preliminary and secondary oceanographic processes like changes in water depth, salinity, temperature, and the speed and direction of currents. It’s often difficult to unravel which part of the tidal process is most influential to a species due to the several covariates related to the change in tides , how inter-related those covariates are, and the elusive nature of the species (like the cryptic harbor porpoise). However, while the analysis is preliminary, if we map the acoustic detections of harbor porpoise over the tidal cycle, we can already start to see some interesting trends between the number of porpoise detections and the phases of the tide. Check it out!

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Now, I won’t promise that I’ll be an excellent coder by the end of the winter, but I think I might have a good chance at being able to mark the “proficient” box next to Matlab and R on my first job application. Yet, whatever your reason for learning code – whether you are an undergraduate hoping to get ahead for graduate school, a graduate student hoping to escape the inevitable (like me), or just someone who thinks getting a code to work properly is a fun game – my advice to you is this:

Google first. If that fails, take mental breaks. Revisit the problem later. Think through all possible sources of error. Ask around for help. Then, when you finally fix the bug or get the code to work the way you would like it to, throw a mini-party. After it’s all over, take a deep breath and go again. Remember, you are not alone!

Happy coding this winter GEMM Lab readers – and I wish you lots of celebratory dancing!

From Oregon to New Caledonia: Crossing latitudes

**GUEST POST** written by Solène Derville from the Institute of Research for Development, Nouméa, New Caledonia. Entropie Lab

Last term I posted about the analysis of Maui dolphin habitat selection I have undergone under Dr Leigh Torres’ supervision at OSU. The results of this work are now compiled in a manuscript which I hope to submit for publication very soon.

Since I last posted on this blog, many things have changed for me: I went back to France at the end of May (with a heavy heart from leaving Newport and my dear lab mates) and I have graduated from the Ecole Normale Supérieure of Lyon and successfully completed my Biology Master’s degree. In September, I will start a PhD on the spatial ecology of Humpback Whales in New Caledonia. I will work at the French ‘Institut de Recherche pour le Développement’ in Nouméa, New Caledonia, under the co-supervision of Dr Claude Payri, Dr Claire Garrigue, Dr Corina Iovan (IRD) and Dr Leigh Torres (GEMM Lab, OSU).

Before telling you a bit more about my project and this summer field season, I would like to introduce the beautiful place where I will be spending the next 3 years. New Caledonia is an archipelago located in the southwest Pacific Ocean, east of Australia. This special overseas French collectivity includes a main island (Grande Terre) and several other islands such as the Loyalty Islands. New Caledonia’s lagoon is the largest in the world and was added to the list of the UNESCO world heritage sites in 2008, because of its exceptional biodiversity including many emblematic species such as humpback whales, dugongs, marine turtles, manta rays…and many others.

).new+caledonia+mapNew Caledonia location in South Pacific Ocean (map: http://springtimeofnations.blogspot.jp

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Map of the New Caledonian Archipelago (map: http://crosbiew.wordpress.com).

Moreover, the ‘Natural Park of the Coral Sea’ was established very recently by the New Caledonian to protect this biodiversity hotspot. This monumental marine park spans 1.3 million square kilometres and is, to date, the largest protected area on the planet. As the detailed management plan for this park will be progressively established in the coming years, there is a local need for more information about marine mega-fauna space use in order to define key areas for wildlife conservation. Thus, the description of the humpback whales ecological niche in New Caledonian waters is the next logical step to initiate conservation planning. The effect of human activities needs to be investigated as the New Caledonian humpback whales population forms an isolated breeding sub-stock and is exposed to mining industry intensification, shipping, harbour construction and boat recreation associated to tourism development.

The general aim of my project is to investigate how humpback whales are using their habitat within and between reproductive areas of Oceania in order to facilitate their conservation at the scale of giant marine reserves (new generation of marine protected areas over vast surfaces exceeding hundreds of thousands of square kilometres). I will therefore focus on the spatial ecology of humpback whales in the New Caledonian Exclusive Economic Zone, with several specific aims:

1/ to quantify the spatio-temporal patterns and dynamics of humpback whale distribution in New Caledonian waters in order to identify key areas for the species and determine if these areas change over time or depending on social context.

2/ to assess the connectivity and movement patterns between areas of interest at individual scale.

3/ to document humpback whale use of habitat in relation to environmental factors and include these results in the broader-context of the South Pacific Ocean breeding areas.

4/ to provide a spatial and temporal assessment of the anthropogenic activities risks to humpback whales in New Caledonia.

I will rely on a large amount of data collected between 1991 and present, and provided by Opération Cétacés (an NGO involved in scientific research on humpback whales and other marine mammals in Oceania since 1996), including boat-based, land-based and aerial observations, satellite tracking and individual-based information (via Photo-Identification and genotyping).

This year, I am taking part in the summer field mission undergone by Opération Cétacés in the South Lagoon. I am currently living in Prony, a little village located along the southern coast of Grande Terre. No electricity, no internet, whale watching from 7am to 4pm on a daily basis: the real life!

In my next post I will tell you a bit more about this field trip with Opération Cétacés but for now, I will let you enjoy these few pictures!

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Prony Bay (© S. Derville)

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Rémi, Claire and Daisy standing next to the “Cap N’Dua” lighthouse from which land observations are made. Whales can be spotted up to 20 nautical miles offshore (© S. Derville) 

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View to the East of Cap N’Dua (© S. Derville)

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Breach observed a few days ago in the South Lagoon (© C. Garrigue)

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Inverted peduncle slap (the whale is lying upside down in the water and energetically slapping the surface with its fluke) (© S. Derville).

An insight into what Marine Mammal Observing is really like!

By Amanda Holdman

It’s August of 2015. That means I have exactly 2.5 months left until my field season and data collection for my masters comes to a close. At the end of October, I will have collected exactly 2 years of visual data on marine mammal distributions off of the coast of Newport, Oregon.

This is a bittersweet moment for me. Currently, I am on a 7 hour flight to Scotland to do some initial data analysis on my collected observations, with the help of a workshop offered by the University of St. Andrews. My first time abroad has me pretty restless with excitement on the plane, but with a 9 hour time change, some good rest will be key to being successful at the workshop. As I try to close my eyes, and picture what the next two weeks of what I like to call “Intensive Distance Sampling Summer School” will be like, the stranger next to me inevitably begins to make small talk, beginning with

“So what do you do?”

I usually tend to answer this question in two different ways. When I’m in my science community, I have no hesitation giving my 3 minute elevator speech on what I have been researching for the past year. However, when I’m making small talk with anyone I tend to just say

“I’m a master’s student studying marine mammals”

And that’s about all you need to say to get everyone’s attention around you! With a little more detail, I explain that I run transects to collect visual observation data of marine mammals to assist with understanding their patterns in distribution and habitat use. This explanation is always followed up with:

“Man, you’ve got the coolest job ever! What’s it like doing this all the time?”

Again most of the time I get this question, I’m usually conversing with people visiting the west coast hoping to see a large gray whale on vacation; or  young children who haven’t yet figured out that marine biology isn’t just about dolphins and pretty coral reefs – but it’s still good to inspire them! Just last week even, I ran into someone on the beach that told me his daughter thinks I’m a rock star for teaching her that you can research the sounds that whales, dolphins, and seals make. (His daughter attended Marine Science Day back in April, and I showed her some recordings of sounds – but I’ll carry this compliment with me for a long time)

But when people ask me how awesome my job is, I tend to keep the morale up and I usually answer

“yep, it’s pretty awesome. I love it! ”

But to be honest, sometimes… it isn’t.

For me, there are four components that equate to a great day of fieldwork: ocean conditions, marine mammals, the boat itself, and equipment (hydrophones, GPS, CTD, camera, etc.)

So in reality…

“The flow of research season goes a lot like this: whales are present, but ocean is impossible; or ocean is calm but the whales are gone; or both whales and ocean are good but the boat breaks down; or everything is working but the rain last night brought in some fog and ruined the visibility” (From Hawaii’s Humpbacks: Unveiling the Mysteries)

AND EVEN on the rare chance that everything goes right – observing marine mammals is hard and uncomfortable – 14 hours of standing with back pain, squinting into the sun until you see one part of the water that looks a little different than the others. I mean really there isn’t much on earth that’s more enormous than the ocean.

This sounds like a lot of negativity, but I am in Scotland currently to resolve some of these minor setbacks we encountered during field collection. Using a statistics program called DISTANCE, we can take into account environmental conditions, sea state, observer bias, etc. When we combine all of these factors together we create a detection function or a ratio of the animals we saw, compared to those we missed. Eventually we end up with an abundance estimate of how many animals are in our study area.

Analyzing the results of my observations this week has provided me with the realization that my time on a boat is coming to an end. In my two years of fieldwork collection, marine mammal observing has molded me into the type of person that has what it takes to do this kind of research: dedicated, tolerant to pain, boredom, and frustration, and most importantly passionate about what I am doing.

Passion is definitely a prerequisite for the life of a GEMM student. Graduate school gives you the chance to be reflective and the time to carefully wade through information. I’ve always had a strong desire to learn, and when I get to combine that with my personal interests, it turns out graduate school can be quite the rewarding initiative.

It’s easy to be discouraged sometimes, especially in an intense and competitive environment like scientific research. I can assure you though, even on our unlucky days, when we’ve swallowed all of the truths about the difficulties of what we do and we’re frustrated enough to give up, our luck turns – usually right when we need it to.

I think the BBC Zoologist, Mark Carwardine, knows just how I feel in saying, “There are few things more rewarding than seeing the worlds’s largest animal in its natural habitat!

Thanks for reading!

Following Tracks: A Summer of Research in Quantitative Ecology

**GUEST POST** written by Irina Tolkova from the University of Washington.

R, a programming language and software for statistical analysis, gives me an error message.

I mull it over. Revise my code. Run it again.

Hey, look! Two error messages.

I’m Irina, and I’m working on summer research in quantitative ecology with Dr. Leigh Torres in the GEMM Lab. Ironically, as much as I’m interested in the environment and the life inhabiting it, my background is actually in applied math, and a bit in computer science.

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(Also, my background is the sand dunes of Florence, OR, which are downright amazing.)

When I mention this in the context of marine research, I usually get a surprised look. But from firsthand experience, the mindsets and skills developed in those areas can actually be very useful for ecology. This is partly because both math and computer science develop a problem-solving approach that can apply to many interdisciplinary contexts, and partly because ecology itself is becoming increasingly influenced by technology.

Personally, I’m fascinated by the advancement in environmentally-oriented sensors and trackers, and admire the inventors’ cleverness in the way they extract useful information. I’ve heard about projects with unmanned ocean gliders that fly through the water, taking conductivity, temperature, depth measurements (Seaglider project by APL at the University of Washington), which can be used for oceanographic mapping. Arrays of hydrophones along the coast detect and recognize marine mammals through bioacoustics (OSU Animal Bioacoustics Lab), allowing for analysis of their population distributions and potentially movement. In the GEMM lab, I learned about light and small GPS loggers, which can be put on wildlife to learn about their movement, and even smaller lighter ones that determine the animal’s general position using the time of sunset and sunrise. Finally, scientists even made artificial nest mounds which hid a scale for recording the weight of breeding birds — looking at the data, I could see a distinctive sawtooth pattern, since the birds lost weight as they incubated the egg, and gained weight after coming home from a foraging trip…

On the whole, I’m really hopeful for the ecological opportunities opened up by technology. But the information coming in from sensors can be both a blessing and a curse, because — unlike manually collected data — the sample sizes tend to be massive. For statistical analysis, this is great! For actually working with the data… more difficult. For my project, this trade-off shows as R and Excel crash over the hundreds of thousands of points in my dataset… what dataset, you might ask? Albatross GPS tracking data.

In 2011, 2012, and 2013, a group of scientists (including Dr. Leigh!) tagged grey-headed albatrosses at Campbell Island, New Zealand, with small GPS loggers. This was done in the summer months, when the birds were breeding, so the GPS tracks represent the birds’ flights as they incubated and raised their chicks. A cool fact about albatrosses: they only raise one chick at a time! As a result, the survival of the population is very dependent on chick survival, which means that the health of the albatrosses during the breeding season, and in part their ability to find food, is critical for the population’s sustainability. So, my research question is: what environmental variables determine where these albatrosses choose to forage?

The project naturally breaks up into two main parts.

  • How can we quantify this “foraging effort” over a trajectory?
  • What is the statistical relationship between this “foraging effort metric” and environmental variables?

Luckily, R is pretty good for both data manipulation and statistical analysis, and that’s what I’m working on now. I’ve just about finished part (1), and will be moving on to part (2) in the coming week. For a start, here are some color-coded plots showing two different ways of measuring the “foraging value” over one GPS track:

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Most of my time goes into writing code, and, of course, debugging. This might sound a bit dull, but the anticipation of new results, graphs, and questions is definitely worth it. Occasionally, that anticipation is met with a result or plot that I wasn’t quite expecting. For example, I was recently attempting to draw the predicted spatial distribution of an albatross population. I fixed some bugs. The code ran. A plot window opened up. And showed this:

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I stared at my laptop for a moment, closed it, and got some hot tea from the lab’s electronic kettle, all the while wondering how R came up with this abstract art.

All in all, while I spend most of my time programming, my motivation comes from the wildlife I hope to work for. And as any other ecologist, I love being out there on the Oregon coast, with the sun, the rain, sand, waves, valleys and mountains, cliff swallows and grey whales, and the rest of our fantastic wild outdoors.

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Southern Sunshine Meets Oregon Wind: Interning with the GEMM Lab!

**GUEST POST**written by Cheyenne Coleman of Savannah State University

My first journey to the west coast, was spent on a six hour flight to Portland, Oregon in anticipation of my upcoming summer internship with the Geospatial Ecology and Marine Megafuana lab (GEMM Lab) at the Hatfield Marine Science Center (HMSC). I had never before been to the west coast, but luckily for me I did not have to make this long journey alone; my friend, Kamiliya Daniels, was also doing an internship at HMSC. After a long bus ride to Corvallis, Kamiliya and I, were warmly greeted by one of my GEMM lab members, Amanda Holdman. With her, was honorary GEMM lab member and Amanda’s dog, Boiler, who spent the greater part of the drive to Newport sleeping on my lap while I spent the drive asking Amanda several series of questions,

“Are there bears in these woods?”

“What do the dorms look like? How do I get around town? I hear it’s a small town, is there at least a Walmart?”

But without any answer to my curiosity, all of these questions were left with one reply:

“I’ll let you see for yourself.”

And then just as Amanda proposed, I did exactly that.

My name is Cheyenne and I am from Savannah State University in Georgia interning with LMRCSC (Living Marine Resources Cooperative Science Center) in Newport, Oregon. My expectations of the Oregon coast and the reality was vastly different than what I had pictured. I imagined the entire West Coast would match a California summer; Sunny and hot.

But on the contrary, upon arrival to Newport, I learned, it doesn’t. It is windy and chilly and hardly ever above 70 degrees. Thinking an Oregon summer would match a California summer, in my suitcase I possessed only three small sweaters and an abundant supply of shorts and tank tops. Needless, to say I was quickly off to buy an Oregon Coast sweatshirt that would double as warmth and a souvenir. Upon first entering Newport, I was mostly shocked at how small the town felt, and I noticed every structure was made of wood, and coming from Georgia this was strange to me. In Georgia, everything is made of bricks and cement. The dorms on first glance reminded me of summer camp for adults: slightly dated with bunk bed sleeping arrangements. Yikes!

However, my worries that come along with moving to a new place, were quickly diminished when I was welcomed to the GEMM lab; Florence greeted with a warm cup of tea, I was introduced to everyone who worked at HMSC, and even given my very own desk in the GEMM lab. After a day of transitions, and a much needed good night’s rest, I was introduced to my project on California Sea Lions (Zalophus californianus).

If you’ve been following along with all of the latest posts from GEMM lab students, you might think the lives of spatial ecologists revolve around glamorous fieldwork. We’ve got Amanda eavesdropping on porpoises, Florence surveying for foraging gray whales, and Leigh playing hide and seek with seabirds down in Yachats. I, however, am admittedly not spending my summer in the field this year and am learning that there is more to being a scientist than picturesque moments with charismatic study species in beautiful locations.

Prior to entering the GEMM lab, I had limited experience in computing and data analysis and spent my prior summer’s doing fieldwork on invertebrates, usually bagging sediment and collecting water samples. This internship was a new and unique opportunity for me to learn the next step of the scientific process. While I had always wondered, “What happens after data collection?” I was not given the experience to find out.  I quickly learned, that this includes a lot of sorting, categorizing, and modeling, all of which are very time consuming.

By using satellite tracking information of California sea lions collected by the Oregon Department of Fish and Wildlife (ODFW) from 2005 and 2007, I am able to measure movements and habitat use of California sea lions. By analyzing their routes between their initial and final locations, we can study their distributions patterns.

To some people, sitting at a computer doing analysis may not seem as glamorous as working in the field. Some people might question why someone would chose to spend their career in front of a computer screen. But my internship this summer, really showed me the value of having experience working at all stages of the scientific process. Seeing all of my efforts in processing, sorting, and categorizing come together to create an end result really enhanced my love for science. By connecting the questions to the answers, and making contributions to the scientific community, I feel rewarded for my hard work.

My internship has come to an end, and given my initial hesitations, I’ve grown accustomed to Newport and the GEMM lab. I enjoy sitting at my desk running through a wild assortment of data and hearing the wonderful ding of the teapot. In the last days of my internship, I was able to escape my computer screen to assist Florence in data collection on beautiful gray whale surveys. Last Thursday, a lab meeting was held and my lab mates and I were able to update each other on our research. We shared ideas on how to enhance everyone’s project, and who might be able to answer questions we were struggling with in our own data sets. As my internship comes to a close, I have gained more knowledge and real life skill then I would ever hope to gain just through courses at Savannah State. I learned new software programs like R Statistical Package and sharpened my own skills in ArcGIS. I gained the experience of collaborating with a lab, and understanding how powerful working with your peers and colleagues can be. Gaining this much experience has, without a doubt, given me an edge in the competitive field I will enter after graduation. I have made connections, hopefully life long, with the nicest people; I know that in the future, which ever path I may choose, I’ll always be a part of the GEMM lab.