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JRBP Ant Survey

About the Jasper Ridge Biological Preserve Ant Survey

Argentine ants are a worldwide invader. Native to Argentina, they were first recorded in the US around 1890 in New Orleans. They arrived in California approximately 15 years later and have spread throughout much of the state. They are considered a pest in agricultural and natural systems.

Graduate student Katy Human and advisor Stanford Professor Deborah Gordon started the Jasper Ridge Argentine ant survey in 1993 to track the invasion of Argentine ants into Jasper Ridge. Twice a year, Katy and undergraduate students searched for ants and recorded their distribution. Five different graduate students from Deborah's lab have continued to lead this survey making it the longest continuous fine-scale study, in our knowledge, of an insect invasion in progress.           

At Right: Fall 2015 Survey Results - Click here for larger image

This long-term study has made important contributions to understanding invasions in space and time and numerous publications have emerged. Early on in the survey, Argentine ants were invading new areas of the preserve rapidly. As they advanced native ants disappeared. Big surges in the invasion occurred during years of high rainfall, and their greatest distribution was attained in 1997-1998, the year of the large El Niño event. Since 2000, the invasion has stalled. There is evidence that native ants are increasingly overlapping with Argentine ants, in particular the winter ant, Prenoelpis impairs seems to be becoming more dominant with time.

  •     Will Argentine ants be able to invade further into the preserve with more time?
  •     How will big rain years and droughts affect their distribution in the future?
  •     How will climate change affect the invasion of the ants?
  •     Are native ants increasingly able to coexist
  •     with Argentine ants? If so, why?

These are just a few of the questions the survey helps us answer. It also provides essential information on the micro scale habitat requirements of this invasive ant - -information that is critical to managing Argentine ant populations. Monitoring efforts like this also provide data for novel testing and learning in the area of species distribution modeling, an important analytic tool in ecology and conservation.

The Gordon Lab and Jasper Ridge have established an ongoing survey program to ensure continued monitoring each year. Survey members include researchers and volunteer from the JR community. The survey takes place on two Saturdays each year, once in the spring and again in the fall. A training course to teach basic skills in identification and data collection is offered prior to each survey.

Matt talks about the volunteer ant survey.

Ant Survey-Desktop.m4v

Training ant survey volunteers

For more information, contact the Ant Survey main email at "antsurveyJRBP @" or Ant Survey Coordinator Angie Nakano "shehulk @"


Ants of Jasper Ridge Field Guide

Ant Species Table

Protocols and Regulations for Jasper Ridge Biological Preserve

Important Health and Safety information for Jasper Ridge Biological Preserve

List of 2015 Ant Survey participants
Matt Bahls, Dave Burr, John Espey, Carleton Eyster, Phil Golden, Paul Heiple, Nicole Heller, Carol Johnson, Crystal Keenan, Phyllis Knudsen, Tom Kussell, Maggie McGuinness, Hal Murray, Jack Owicki, Jovel Queirolo, Dan Quinn, Elizabeth Ricano, Gary Smith, Marguerite Stevens, Merav Vonshak, Hans Weber, Sara Witt

Previous Participants