Friday, April 29, 2011

Turning off the heat: Impacts of power plant decommissioning on green turtle (Chelonia mydas) research in San Diego Bay, CA USA

Turning off the heat: Impacts of power plant decommissioning on green turtle (Chelonia mydas) research in San Diego Bay, CA USA

Paper currently in review.


Green turtles (Chelonia mydas) are among the most high profile species in San Diego Bay, California, and understanding impacts of coastal development and industry is essential to the management and conservation of this local population. Here we describe power plant changing energy production and its impact on turtle habitat use and our ability to research and manage this population.

For over 20 years, green sea turtles have been captured, assessed and tagged near the South Bay Power Plant (SBPP) in the San Diego Bay; from 2002-2009, 73 turtles were captured on 173 occasions. As the 50-yrs old SBPP generates less energy, effluent patterns change and water temperatures decrease, presumably to more natural conditions. There has been a concurrent decrease in turtle-capture success, perhaps due to lesser visitation to the effluent site where nets are tended. Seasonal catch-per-unit-effort declined from a high of 4.14 turtles per monitoring day, to a seven-year low of 1.45 during the 2008-2009 season. It is already apparent that management decisions related to energy policy are affecting the habitat and behavior of this stock of endangered turtles. Green turtles are expected to remain in the San Diego Bay after the SBPP becomes inoperative and continuing research will monitor future impacts and distribution shifts resulting from the expected changes in thermal pattern within south San Diego Bay. Research efforts to study this population (i.e. capture methods and locations) will require modification in response to these changes. Lessons learned here are applicable to the immediate coastal development of San Diego, as well as at similar interactions between marine turtles and industrial thermal effluent discharge throughout Southern California, the United States and beyond.

PDF version of poster available

PDF draft available by contacting author

Key References

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Deutsch, C.J., 2000. Winter movements and use of warm-water refugia by radio-tagged West Indian manatees along the Atlantic coast of the United States. Final Report prepared for the Florida Power and Light Company and U.S. Geological Survey. 133 pp.

Dutton, P. and D. McDonald. 1992. Ultrasonic Tracking of Sea Turtles In San Diego Bay. In J.I. Richardson and T.H. Richardson (Compilers), Proceedings of the Twelfth Annual Workshop on Sea Turtle Biology and Conservation (pp. 218-221). Washington DC: NOAA Technical Memorandum NMFS-SEFC-361.

Eguchi, T., J. A. Seminoff, R. LeRoux, P. H. Dutton, D. M. Dutton. 2010. Abundance and survival rates of green turtles in and urban environment: coexistance of humans and an endangered species. Marine Biology DOI:10.1007/s00227-010-1458-9.

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Thursday, April 7, 2011

Calling All Teachers!

Bringing the Ocean and Sea Turtle Science into the Classroom
Thursday, April 14th 4:00 - 7:00 pm
Town and Country Hotel
San Diego, CA

Registration Deadline Extended to April 10!
The International Sea Turtle Society convenes a uniquely important four-day symposium each year that brings people together from all around the world (more than 1,000 people from over 80 countries!), all dedicated to the research and conservation of sea turtles. The 2011 Symposium marks the return of this meeting to the U.S. for the first time in four years, and it will be the first-ever Symposium hosted on the U.S. west coast! The theme of this year’s meeting is The Next Generation of Research and Conservation. Throughout the week, major efforts will be made to recognize and support student contributions to the Society and to advancing research and conservation of sea turtles around the world.

The Symposium is partnering with the Ocean Connectors program to host a special Teachers Workshop on April 14! This unique educational workshop will be provided FREE of charge and will focus on ocean conservation through the biology of sea turtles while meeting state learning standards. Special guest speaker Dr. Wallace J. Nichols, world-renowned sea turtle biologist, will commence the Teachers Workshop with a thought provoking and inspiring lecture on "Oceanophilia: The Neuroscience of Emotion and our relationship to the Ocean (and sea turtles)". Following the lecture, teachers will be introduced to online resources and classroom activities to inspire the next generation to protect, understand, study, and respect our oceans. Participants will receive 3 hours professional development credit.

Register for this free workshop by e-mailing Frances Kinney at
Please provide the following information:
1) Full Name
2) Name of School, District, and Grade Level
3) E-mail and Phone Number

Please help us spread the word about this special opportunity – invite a fellow educator to join the Teachers Workshop!

Enrollment confirmation and Workshop details will be sent via e-mail. For more information, please contact Frances Kinney at or Barbara Andrews at

Marine Turtle Conservation: a diagnostic tool for success

By Cali Turner Tomaszewicz, Danielle DiIullo, Aly Fleming, and Michelle Lande

About the Project

Marine turtles, as a group, are some of the widest ranging animals on the planet. They are adapted for almost every marine habitat from the ocean's surface to depths of up to 1000m, from one side of an ocean basin to the other and then up onto the beaches at the ocean's edge. Despite this miraculous range and flexibility, all seven species of sea turtles are threatened or endangered, some even critically. In addition, most nesting takes place in countries that lack the resources to properly protect the turtles. Fortunately, in recent decades, the world has begun to notice and efforts to promote conservation have been initiated in coastal nations around the globe.

These conservation initiatives range in scale from local community operations to international NGO projects. While nearly all efforts are well-intentioned, not all have experienced great success. Just as marine turtles' range is so broad, so are the threats that face them, making their preservation extremely challenging.

By examining a wide range of conservation projects and much of the relevant scientific literature, we have created this website as a diagnostic tool in hopes that it will aid current efforts. There are seven elements to our Diagnostic Tool that we feel have been demonstrated by many conservation groups as crucial elements of a successful conservation program. We have focused here on the socio-economic and cultural components of marine turtle conservation. We feel these are just as integral to successful conservation as basic biological principles.

1. Base foundation on local socioeconomic and cultural conditions and practices

2. Match varying scales – ecological, spatial, social

3. Harness local and external knowledge

4. Facilitate and utilize a strong, responsive legal capacity

5. Identify and address limitations

6. Promote longevity and adaptability

7. Share and learn from practices

More Information

How to Use the Diagnostic Tool
Creating the Framework
How to Define Success
What is Least-Cost?

Comments and questions may be addressed to co-author: Cali Turner TomaszewiczContact: - Will also be available at the 2011 ISTS.

Other co-authors:, Dani DiIullo, Aly Fleming and Michelle Lande

Created as a graduate project at Scripps Institution of Oceanography’s Center for Marine Biodiversity and Conservation, University of California, San Diego

(c) 2008