Violet Compton, PhD candidate

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