Josh holds up a giant kelp bass (Paralabrax clathratus) caught in Point Loma, CA (Credit: Josh Brower)

Scary predators stress small fish

Stress is a part of everyday life, even for animals.  Everyone has experienced how stress can affect our mood, appetite, and interactions with others.  Animals have similar reactions when stressed and experience many stressful events ranging from extreme temperature to antagonistic encounters with other animals.  Stressful disturbances may cause animals to change their behavior and move more cautiously or seek shelter.  Animals also experience a physiological stress response that affects metabolism which, in conjunction with behavioral changes, can have a negative impact on the animal’s well being.  Recently, many researchers have tried to understand how human impacts affect animal stress, however, the stressful effects of natural events in the wild are still poorly understood.  Certainly, the threat of predation can cause stress for animals in the wild.  Like many organisms, fish are most vulnerable to predation when they are small, during early development.  Stress during early development may have important consequences for fish later in life.  My research focuses on the effects of stress due to predation threat on juveniles of the local species the giant kelpfish.  Specifically, I use kelp bass and juvenile giant kelpfish as a model predator-prey system to examine how kelpfish respond to the stress of predation threat both behaviorally and physiologically.  I quantify the physiological stress response of kelpfish to predation threat by measuring the amount of the hormone, cortisol, that kelpfish produce.  I pursue these research interests through a series of laboratory and field experiments based at CMIL.

Josh measuring fish stress hormones in San Diego Bay (Credit: Josh Brower)

About me

Growing up on a barrier island along the east coast of central Florida I had a close relationship with the water.  I always wanted to know how things work, a desire I continue to have today.  As I spent a lot of time at the beaches and lagoons surrounding my home the desire to know how things work expanded to include the biological workings of my surroundings.   When I started my undergraduate degree at Florida State University (FSU) I knew that I wanted to study biology, however, I was unsure which discipline in biology appealed to me most.  Luckily, I had an opportunity to study abroad at James Cook University (JCU) in Cairns, Australia during my sophomore year.  My coursework at JCU included many field trips into environments ranging from coral reefs, to savannah lands, to tropical rainforests.  The experience of studying ecology and exploring the natural environment in Australia solidified my interest in ecology.  Upon my return to FSU I was accepted into the Certificate program in Marine Resource Ecology and Conservation.  Through the certificate program I worked on research projects both in groups and individually.  All of these experiences contributed to my desire to continue my studies in marine ecology after graduation which brought me to the M.S. program at San Diego State University.

Research interests

Broadly, my research interests lie in ecology, understanding the factors driving interactions among organisms and the environment.  I am particularly interested in the interactions between predators and their prey and how habitat composition can affect those interactions.  I am also interested in how stress resulting from both human impacts and natural interactions can affect organisms in the wild.

Josh and alumni Renee Dolecal boating towards a dive site in Point Loma, CA (Credit: Josh Brower)

A day in the life

My day as an ecologist can vary greatly depending on the task at hand.  Some tasks require me to work with aquaria at the marine lab, or SCUBA dive to collect fish, while others bring me to our laboratory on campus to conduct chemical analyses of the fish from my experiments.  When I am running experiments my day starts early (generally an hour before sunrise) because the kelp bass that I use in my experiments are most active at dawn and dusk.  Maintaining holding tanks to keep fish alive and healthy for my experiments is also an important part of my daily routine.  Fish must be fed every day and tanks cleaned once to twice a week.   I enjoy how each day of research brings new challenges to think through and overcome.

Giving back through science

Underprivileged children have few opportunities to experience the outdoors and frequently view science as inaccessible.  People who spend time in natural environments are healthier both mentally and physically than those who spend all their time in urban environments.  I have seen the positive effects of bringing youth into the outdoors, firsthand, through volunteering with Outdoor Outreach (OO).  OO is a San Diego based organization with the mission “to empower at-risk and underprivileged youth to make positive, lasting changes in their lives through comprehensive outdoor programming.”  I have found it very fun and rewarding to teach OO participants about local environments through activities like hiking, snowboarding, kayaking, and even learning to swim.  There are many great outreach organizations in San Diego, get out there and volunteer!  You never know what you might gain in the process.

(Credit: www.jasonwardstudios.com)

Check out this video about the Coastal and Marine Institute and our connections with the world around us.

https://www.youtube.com/watch?v=ElQZ3ncRkuQ

Directed by Kevin Shanmugam and Daniel Galuppo

Script by Alex Warneke

Produced by the Marine Ecology and Biology Student Association

Schedule of events

10:00 am    Doors Open!

11:00 am     Faculty Presentation

11:30 am     Guided Lab Tour

12:00 pm    Raffle

 1:00 pm     Faculty Presentation

 1:30 pm     Guided Lab Tour

 2:00 pm     Raffle

 3:00 pm     Doors Close

Lecture titles and information

11 am – Talk by Dr. Jeremy Long, Assistant Professor of Biology

Title of Presentation: Things that suck in salt marshes

Research Interests: I study how the interactions of predators and prey shape several marine communities including salt marshes, rocky shores, and subtidal habitats. I am fascinated by the chemicals plants and animals make, and the roles these chemicals play. I like to bring science to a broader audience through music videos.

1 pm – Talk by Dr. Matt Edwards, Assistant Professor of Biology

Title of Presentation: The amber forest: what’s in there?

Research Interests: The goals of my lab are to study the physiology, population biology, ecology and biogeography of seaweeds, with an emphasis on eastern Pacific kelp forests. Our research integrates organismal biology, population and community ecology, and a strong emphasis on quantitative and experimental techniques to assess spatial and temporal patterns in coastal marine communities. Members of our group do field research in California, Washington, Alaska, Mexico, Chile and Peru on topics ranging from dispersal and dormancy in marine seaweeds to the effects of global warming and El Niño-Southern Oscillations on their latitudinal range limits.

Lee with a juvenile California spiny lobster, another species studied by the Hovel Lab (credit: Christopher Millow)

Nursery habitat for juvenile halibut

Being a tiny fish isn’t easy!  Throughout the course of their lives, many fishes move from the open ocean to coastal nursery habitats, and then back to deep off-shore areas.  All that traveling leaves them vulnerable to lots of predators and variable food resources.  Fish mortality is especially high when they’re very young, so ending up in a nursery habitat with plenty of food and places to hide from predators is critical to allow them to grow up to be successful adults.  The goal of my research is to determine the pros and cons of the coastal nurseries available to juvenile California halibut in San Diego.  I conduct experiments in San Diego Bay to learn about juvenile halibut habitat preference, and about their ability to find prey and avoid predators in different habitat types.

Unlike most fishes, halibut are flat and have both eyes on the same side of their head.  This body plan allows them to sit on the bottom, where their dappled-brown color helps them to blend into the sediment. Because halibut are so well camouflaged in sandy habitat, benefits of highly-structured habitat like eelgrass has been largely overlooked, despite its well-documented benefits to other juvenile marine organisms.  Eelgrass provides rich prey resources and lots of hiding places.  My research shows that access to eelgrass and to sandy habitat may be important to halibut.  Juvenile halibut show a strong preference for eelgrass in habitat choice experiments, but their survival is significantly higher in sandy habitat where they can bury themselves easily.  Interactions between juvenile fishes and their habitats affect their growth and survival.  Learning about these interactions is important for understanding how nursery habitat quality and availability allow juvenile fishes to grow into healthy, successful adults.

Juvenile halibut (Paralichthys californicus) (Credit: Stacey Virtue)

About me

I grew up on the Maine coast, where I spent lots of time in and around the ocean.  I always wanted to be a marine biologist, and my undergraduate career at the University of California, Santa Cruz solidified my interests in the scientific process and in marine science.  One of the best things about pursuing marine biology is the opportunity for travel and for conducting research in a variety of ecosystems.  As an undergrad, I participated in and conducted my own field research throughout California and in French Polynesia.  Since I graduated I’ve been involved in research with organisms as diverse as American lobsters in Maine, endangered North Atlantic right whales in Cape Cod, and tropical corals and algae in Belize.  My current adventure is pursing my Master’s degree in ecology at SDSU in Dr. Kevin Hovel’s lab.

Ready to take the plunge! (Credit: Rick Wahle)

My research interests

I’m interested in the ecology of commercially important marine species, especially the behaviors and processes that affect juveniles.  Growing up on the Maine coast, I was exposed the cultural and economic importance of fishing, and as I learned more about marine science I quickly learned about the effects fishing has on marine populations and ecosystems.  Fisheries biologists and managers pay close attention to fluctuations in populations of adult fishes.  These fluctuations are the combined result of fishing pressure and population resilience – the ability of adults to reproduce enough to replace losses due to fishing and natural deaths.  Robust adult populations depend on healthy juveniles.  The goal of my research is to better understand the interactions between juvenile halibut and the potential coastal nursery habitats they are delivered to as larvae.

Floating tags make small halibut easy to spot underwater – even when they’re buried under a layer of sand. (Credit: Lee Reeve)

A typical day in the life…

I think jumping in the ocean is the best possible way to start the day.  I usually get to the CMIL early and head straight to my field site in San Diego Bay with a dive buddy.  All my experiments are done underwater, so we put on our SCUBA gear and descend!  After setting up experiments or collecting data, we head back to the beach and pull a large net called a seine through the water to collect halibut to use in later experiments.  Back at the CMIL, I spend the rest of my day taking care of the fish I keep there, building and repairing field equipment, sorting and identifying samples of halibut prey under the microscope, and working on other Hovel Lab projects.

Lee and Alex collect and measure juvenile halibut using a beach seine. (Credit: Jeffrey Lamont Brown, Tallgrass pictures)

Why is being a biologist awesome?

I love being a marine biologist because it’s such a fun challenge.  In the course of a day, I need to be able to think critically and creatively to design effective experiments, design and build specialized equipment, do physically challenging field work, and be detail-oriented as I enter and analyze data and identify tiny organisms under the microscope.  Biology is a truly collaborative field, and I love meeting and working with other scientists.  CMIL students and faculty work together closely, and I value having the opportunity to help out with and learn about other researchers’ projects.  We all come from different backgrounds and have experience in different aspects of marine science; it’s awesome to have access to so many great minds!

Lee and her thesis advisor, Dr. Kevin Hovel, collaborate on research projects at CMIL. (Credit: Jeffrey Lamont Brown, Tallgrass pictures)

Fun Fish Facts!

• Halibut fossils have been found in Southern California from as far back 5.3 million years ago.
• California halibut belong to the family of left-eyed flatfishes, but just as there are right- and left-handed people, only around 60% of CA halibut have eyes on the left side – the other 40% are right-eyed.  This phenomenon is quite rare among flatfishes; the side with eyes is often a defining feature in flatfishes.
• Adult CA halibut can grow to 5 feet long and weight 70 pounds.  Their relatives, Pacific halibut, can grow to 9 feet long and weigh 500 pounds!

Renee holding a lobster. Photo credit: Renee Dolecal.

Many marine predators are dependent on their sense of smell to find their food. However, this can prove to be quite challenging if the animals they are preying upon are particularly good at hiding their stench. Prey do not want to be found and eaten and go to great lengths to hide their smell. Because of this, many animals do not become detectable until injured, as damaged tissues “bleed” more potent and distinguishable chemicals that predators often find highly attractive. However, most of the animals that predators eat are not walking around the seafloor like a bunch of zombies with their limbs falling off. So how else can they find prey if they are not stinky or injured? Terrestrial studies have suggested that plants may help predators find their prey. For example, when herbivores (or plant eaters) munch on plants, the plants themselves release chemicals that signal they are under attack. Predatory insects and parasitoids are able to use the plant signals to find their food from a distance. Unfortunately, there are only a few examples of this in the ocean, and it remains poorly understood.

My research aims at understanding how kelp forest predators, like lobsters, find their herbivorous prey, and whether chemical cues released from seaweeds are important to their hunting strategies. What I have found is that kelp forest predators are not able to use cues released from common seaweeds like giant kelp and sea lettuce to find herbivores munching on their tissues. However, herbivores do become more attractive when injured. Not surprisingly, I have also found that kelp forest predators find bait fish highly attractive. While this may not seem like new information to share with fishermen, it does highlight an important observation about foraging predators. Predators that use their sense of smell to find food and can tell from a distance which food items are more valuable and vulnerable. Fish are a rarely encountered and valuable food source, while injured herbivores are a vulnerable type of “fast food.” This is important to understand because we often assume that live prey are the most important food items in predator diets. This may not always be the case, as live herbivores are not easily found relative to other more attractive cues like crushed urchins and dead sardines.

A little about me

Like many marine biologists, my love of the ocean began when I was young, spending lots of time on the beaches of Long Island, NY. However, it was during my undergraduate years at Northeastern University that I discovered my desire to become a scientist, by participating in a field intensive study abroad program called Three Seas. Through this program I traveled across the world to study rocky intertidal, coral reef, and kelp forest ecosystems. It was here that I was exposed to the rigors of science, the excitement of discovery, and satisfaction of conducting independent research. Shortly after completing this program, I completed my B.S. degree in Biology with a concentration in Marine Biology, and began work as a research assistant, working with several prominent marine ecologists at Northeastern University’s Marine Science Center. After deciding that I wanted to continue marine ecology as a career, I joined Dr. Jeremy Long’s lab here at SDSU and am currently working towards completing a Master’s degree in Ecology.

Renee collects kelp in the field. Photo credit: Renee Dolecal.

My research interests

I find myself constantly inspired by different ideas, and have many broad interests as they pertain to community ecology in marine ecosystems. More specifically, I enjoy studying chemical ecology, investigating how chemical cues affect species interactions and community structure. For my master’s thesis, I am looking at the chemical cues released by seaweeds when eaten by herbivores, and how they influence predator foraging. Scientists on land have long studied this type if interaction between plants and arthropod insects, but we still have a poor understanding of how common this is in the ocean. The goal of my research is to help shed light on these poorly understood interactions to learn how predators find their prey, and gain a more broad appreciation for how chemicals influence marine community structure.

A typical day in the life…

More like a typical night in the life. Most of my research has to be done at night because I study benthic predators, like lobsters, which actively forage after dark. During the day I spend my time preparing for field experiments and entering data, but at night is where the fun begins where I collect my data and observe predator behavior. What are the perks of being a night owl? Some of the coolest things happen at night when the rest of the world is sleeping – incredible glowing water created by bioluminescent phytoplankton blooms, and daily Sea World fireworks displays lighting up the summer night sky.

Renee measuring a lobster during night sampling. Photo credit: Renee Dolecal.

Why is being a biologist awesome?

I love being a marine biologist because I feel like I am able to see and experience so many cool places and things that most people will never experience in their lifetime. It’s amazing to get to study such an extraordinary world under the sea that we have just barely begun to understand. The opportunities of exploration and discovery seem endless, and I am always excited by anything new I learn about it.

Fun project facts

• Believe it or not, the study of how plants attract predators has a practical application – biological pest control. Terrestrial ecologists have long studied how plants attract predatory insects to figure out natural ways to control herbivorous pests from destroying important crops like corn, tobacco, tomatoes, and legumes.
• Seabirds and penguins can use cues coming from phytoplankton blooms to find herbivorous prey like krill and small fish from 100’s of kilometers away!
• The idea that predators can use plants to find their food has also been referred to as the “bodyguard hypothesis.” As predators remove or parasitize herbivores eating plants, they alleviate the amount of damage caused by herbivore grazing, allowing the plant to survive.

Violet holding California killifish in her hand. Photo credit: V. Compton

You’ve probably heard the story about pesticides and how bad they are for the environment, but have you ever really thought about who they hurt and how? Pesticides don’t just kill those pesky little critters in your bed; they are applied to almost every type of crop and object you can think of and many of them can be carried by rainfall into nearby streams and estuaries where they can directly harm fishes and invertebrates. The goal of my research is to understand the effects of pesticides on the behavior of fishes, and how this affects their survival and interactions with other species. I have found that exposure to pesticides at concentrations similar to those you would find in the environment can reduce the ability of fishes to swim normally, socialize, feed on prey, and avoid predators. This implies that even small amounts of pesticides that are found in nearby watersheds can alter the ecology and survival of fishes in many subtle but important ways. My research helps scientists and policy makers understand the ecological consequences of very low concentrations of these chemicals in marine and estuarine environments. A greater understanding of these ecological effects can help us to effectively manage and conserve all kinds of fish species in degraded habitats.

A little about me

Unlike many marine ecologists, I grew up a long way from the ocean on Lake Huron in Ontario, Canada. Despite my distance from dynamic marine ecosystems, they were all I could think about during my youth. Luckily, the unique aquatic environment provided by the Great Lakes provided me with the spark to learn about fishes and the multiple threats to their health, ecology, and persistence. Before long, my interest grew into a passion and the motivation to join the fish ecology lab of Dr. Todd Anderson at San Diego State University under the Joint Doctoral Degree in Ecology (JDPE) with the University of California Davis.

My research interests

The goal of my doctoral research is to blend ecology and ecotoxicology to better understand the effects of pesticides on the behavior of fishes, and the consequences this might have for their ecology and survival. I study the changes in ecological behaviors of fishes after exposure to pesticides at concentrations that are typically found in coastal marine environments such as estuaries and marshes. Estuarine environments provide many important benefits for humans and host an impressive diversity of plants and animals – however they are also commonly the most polluted coastal habitats. By understanding the subtle effects of very low concentrations of chemicals on fishes we can effectively manage the water quality in degraded estuarine or marine habitats, and better conserve all kinds of ecologically and commercially important fish species that live in these habitats.

For my current research I am studying the behavior of a common and small but pretty darn cute estuarine fish species, the California killifish, Fundulus parvipinnis. The first goal of my research is to determine whether individual fish have consistent behavioral traits; just like you have a personality, so do fishes! To do this, I study fish one at a time to observe correlations in their behaviors such as their willingness to explore an unfamiliar environment, to spend time away from their fellow fish, and to forage before and after a predator attack. My second goal is to investigate how individuals behave differently when exposed to low concentrations of a common and toxic pesticide, chlorpyrifos. So far I have found that many fish exposed to the pesticide are much less active and spend much more time closer to the surface of the water, spend less time with their fellow fish, do not forage readily and have a slow reaction to a model bird predator. This indicates that these fish may be at a greater risk of death by starvation or being eaten by a predator.

Making behavioral observations of killifish. Photo credit: V. Compton

A typical day in the life…

The majority of my days are generally spent doing two things: taking care of my little fish, and observing their behavior. To be happy and healthy the fish need daily water changes and feeding, and are frequently removed for a health checkup (measuring their weight and length, and the presence of any parasites or wounds). When I am not in the lab, I am often exploring new marsh sites where I can collect my experiment fish with large seine nets. This is one of my favorite parts of the job – playing outside in the mud and seeing what cool new species I will find each day.

Capturing killifish with a minnow net. Photo credit: V. Compton

Why is being a biologist awesome?

You get to play outside and study a lot of different and fascinating habitats! I love exploring all kinds of marine environments – from muddy marshes to underwater reefs while scuba diving. I also get a rush doing research that can one day help us better understand and protect marine organisms and their environment.

Pesticide facts

• In 2010, approximately 1,370,559 lbs of active pesticides were applied throughout San Diego county making it the 23^rd highest county in California (CDPR)
• Who applies all these chemicals? You might think that farmers are mainly responsible for pesticide problems, but more than half of California pesticide use is in urban areas — by residents, home gardeners, and pest control professionals in and around schools, businesses, and homes;
  http://www.centralsan.org/documents/Pesticides_and_Water_Pollution.pdf
• Pesticide use in California rose in 2010 after declining for four consecutive years. More than 173 million pounds of pesticides were reported applied statewide, an increase of nearly 15 million pounds – or 9.5 percent – from 2009 (California Department of Pesticide Regulation);

  http://www.cdpr.ca.gov/docs/pressrls/archive/2011/111228.htm

How can I find out more about pesticide use around me?

• The California Department of Pesticide Regulation (DPR) Pesticide Use database provides information by county about application of pesticides by various licensed pesticide users: http://www.cdpr.ca.gov/
• The Less Toxic Home and Garden:

  http://www.centralsan.org/index.cfm?navid=586

• Assessing the health risk of pesticides:

  http://www.cdpr.ca.gov/docs/dept/factshts/artic12.pdf

• Helpful usage tips: Use suggested products according to label directions and dispose of unwanted or leftover pesticides at a household hazardous waste collection facility or event. For more information on pesticide disposal, call 1-800-CLEANUP or visit: www.1800CLEANUP.org

  http://www.centralsan.org/documents/Pesticides_and_Water_Pollution.pdf