Humboldt squid Dosidicus gigas live in the Pacific Ocean, historically from Chile to Mexico. They are the largest squid in the family Ommastrephidae: they can grow up to six feet long (including tentacles) in less than two years. And each female can produce over 30 million eggs!

In the past decade, Humboldt squid have been spotted and caught further and further north. They now are found not only in the Pacific Ocean from Chile to Mexico, but seasonally are also found off California, Oregon, Washington, British Columbia, and even Alaska. This incredible expansion of their range could be facilitated by human activities (including anthropogenic climate change) and has the potential to greatly impact ecosystems and fisheries. Humboldt squid can be considered “invasive species” because of their role in new ecosystems, despite the fact that they were not directly introduced by humans (which is the traditional definition of invasive species).   

Humboldt squid support a huge fishery: in 2007 it was the 14th largest one in the world, measured by tons according to FAO*. That makes them the second largest invertebrate fishery in the world (recently demoted from being the first in 2006). Despite being so intensely fished, little is known about their biology or behavior. Their recent invasion to California is an incredible opportunity to understand these squid and their ecology from a variety of angles before there is intense fishing pressure in California. My work will hopefully be able to help inform a fisheries management plan, if one is developed for Humboldt squid in the U.S.

I grew up in the San Francisco Bay Area and completed my bachelor’s degree in marine biology at UCLA in 2004.  Before beginning my PhD at Stanford in 2006 I worked as a volunteer with Dr. Gilly studying the fish-eating behavior of the California cone snail Conus californicus.  I am very interested in the interface of science and policy, particularly in the effective communication of science. I travel often, speak French and German, and have lived abroad in several countries.

My work is driven by three main questions regarding Humboldt squid in California.

Why are they here? What are they doing here? What impacts will this have? 

I attach pop-up satellite tags onto large Humboldt squid. These tags record temperature and depth time-series data, from which I am able to learn about their diving behavior, migration patterns and habitat preferences. This is part of the Tagging of Pacific Predators (TOPP) program, and our lab has tagged numerous squid in the Gulf of California as well. Part of my work will be to compare squid behavior in warm waters of Mexico to cold waters of California. I am interested to identify whether they spend comparable time in midwater environments with low oxygen (oxygen minimum layers), which is behavior we have seen in Mexico.

I am also collaborating with researchers at the Monterey Bay Aquarium Research Institute (MBARI), and am working with an incredible data set of deep-sea footage. MBARI’s data documents Humboldt squid presence in Monterey Bay since 1997, and I am trying to identify patterns in their seasonal invasions and migrations. I aim to determine whether there are oceanographic properties that correlate with Humboldt squid presence and abundance. With data from MBARI, I will also create an estimate of abundance, something that is important for assessing impacts of squid presence to California ecosystems and for managing fisheries.

*2007 FAO report: ftp://ftp.fao.org/fi/stat/summary/a1e.pdf

jules32 at stanford dot edu