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Jim Maddy, President and CEO

Jim Maddy is a nationally recognized leader in conservation policy and advocacy. Since joining the Association of Zoos and Aquariums (AZA) in 2006, he has implemented an aggressive and successful plan to improve Association member services. Under his leadership, the AZA has developed new corporate partnerships and built organizational capacity.

Jim previously served as President of the National Park Foundation (NPF) for nine years. There, he worked to strengthen the connection between the American people and their National Parks by raising private funds, making strategic grants and increasing public awareness.

Prior to NPF, Jim served as President of the League of Conservation Voters (LCV) through four federal election cycles. LCV is the independent political voice for the environment, and Jim built the organization into a significant force for injecting sound environmental policies into the federal electoral process.

Jim broke ground as the first Executive Director of the Western Governors' Association (WGA). At WGA, Jim developed policies and programs in the areas of natural resources, the environment, human services, economic development, international relations and state governance.

Jim's service on the Board of Directors for The Center for Clean Air Policy has put him at the forefront of climate policy and air quality issues since 1985. Jim is a founding board member and serves on the executive committee of the board.

As an active member of the Board of Directors of the Student Conservation Association (SCA), Jim is working to advance public service on behalf of the environment. SCA recruits over 3000 students at over 400 public land sites for ecological restoration, wildlife management, and environmental education. Jim chairs the audit committee.

Jim holds an M.A. in Economics from West Virginia University.

Jill Nicoll, Chief Operating Officer

Jill is a member of the Executive team and oversees all aspects of member services including conferences, membership, professional development, education, member communications, advertising, digital media, marketing as well as revenue generation activities. She is also responsible for the day to day operations of the AZA.

Jill joins the AZA with 20 years’ experience, most recently as a marketing consultant and prior to that as Executive Vice President and Chief Operating Officer at the National Park Foundation. Before joining the National Park Foundation, Jill was a PR Manager at United Media in NY, where she handled the partnership with Charles Schulz and the PEANUTS characters. Jill holds a Bachelor’s Degree from Franklin and Marshall College in Lancaster, Pennsylvania, and currently lives in Bethesda, Maryland with her husband, two kids, one cat, one dog and one fish.

Kris Vehrs, J.D., Executive Director

Kris is responsible for internal and staff operations functions at AZA. She provides counsel to the Association including review of contracts, bylaws changes, accreditation and ethical issues. Kris works with the Board of Directors to determine the focus of the Association.

Kris began working for AZA in 1979 when AZA was represented by the firm of Steele and Utz. Kris served as the Director of Government Affairs from 1981 until March 2000. Kris has a law degree from George Mason University.

Barbara Pueschel, B.A., Board and Committee Liaison

Barbara joined AZA as executive assistant to the Executive Director in 2004, shortly after returning to the US from Dominica. Her responsibilities at AZA include providing administrative support to the Board of Directors, AZA Committees and the Executive Director.

Barbara has worked in independent education since 1985 primarily in development and publications. She has a B.A. in History and English from the University of California at Santa Barbara and has taken graduate courses in Art and Literature from Wesleyan University.

Phil Wagner, Senior Vice President, Finance

Phil manages the financial affairs of the AZA, including budgeting, financial reporting, payroll, IT and cash management. His goal is to ensure that the AZA staff members have the financial tools they need to achieve their missions, while maintaining a secure financial position for the Association.

Phil joined the AZA in December, 2011, with over 30 years in accounting, including stints in Big Four Public Accounting, Retail, Telecommunications and Not-for-profit. His career includes 2 ½ years as Controller at the Maryland Zoo in Baltimore.

He holds a Bachelors Degree in Accounting from Loyola University in Baltimore, and is a Certified Public Accountant.

Ana Maria Sanchez, Controller

Nancy Ramos, Receptionist and Accounting Assistant


Denny L. Lewis, M.B.A., Vice President Accreditation Programs

Denny Lewis has had a career developing and managing certification and accreditation programs primarily in the scientific professions, including the American Institute of Chemists, the National Certification Commission in Chemical and Biomedical Engineering, and the Association For The Advancement of Medical Instrumentation.

A native of Washington, DC, he came to AZA in 1998 with a passion for wildlife that began as a child and continued through college, where he majored in business and studied zoology in elective courses. He holds an M.B.A. from the University of Maryland.

Jennifer DiNenna, B.S., Manager, Accreditation Programs

Jennifer manages the Accreditation and Certification process, including accepting applications, setting up inspections, maintaining and updating records, and preparing for accreditation hearings.

A native of Maryland, Jennifer earned a degree in Zoology from the University of Maryland. She then obtained a Certificate of Accomplishment from Animal Behavior College. Prior to joining AZA, Jennifer was a manager of a pet sitting, boarding and day care facility. She then decided to follow her passion for exotic animals at AZA.

Jennifer is also a Professional Positive Reinforcement Canine Trainer. She continues to instruct obedience classes in her spare time.

Conservation and Education

Paul Boyle, Ph.D., Senior Vice President for Conservation and Education

Dr. Paul Boyle leads the Association's conservation education and science programs. He has over twenty-five years experience creating and directing conservation programs, environmental research, public education, and exhibit programs. He founded The Ocean Project in 1997, a global initiative to increase public awareness of the crucial roles the ocean plays in human survival and to engage people in becoming personally involved in being a constituency for the ocean.

Paul was Director of the New York Aquarium and its Osborn Laboratories from 2002 to 2006. He has served on the AZA Board of Directors and as liaison to the Board of Regents and the Charter and Bylaws Committee. He also chaired ADISC, and served as an advisor to the Animal Welfare Committee.

He earned a B.A. in Biology and Marine Science at Northeastern University, a Master's in Environmental Engineering at Harvard University, and a Doctorate in Applied Environmental Sciences, also at Harvard, and graduated from the Wharton School's Executive Management program.

Debborah Luke, Ph.D., Vice President for Conservation & Science

Dr. Debborah (Colbert) Luke joined AZA in September 2008 as the Vice President of Conservation and Science and is responsible for furthering standards of excellence in all aspects of animal care and population management within our accredited institutions and advancing AZA's conservation, science, education, and stewardship initiatives.  She works with the Senior VP, Board of Directors, a multitude of Committees, Scientific Advisory Groups, and Animal Programs and is responsible for relationship building with regulatory, government and non-government agencies, universities, and other related organizations.

Debborah has over 19 years of experience in the aquarium and zoological field.  As the Manatee Care and Training Coordinator at Mote Marine Laboratory & Aquarium, she has an extensive background of scientific research experience with both captive and free-ranging marine mammals, with a particular focus on manatee sensory biology and animal training, and considerable cetacean and sea turtle stranding and care experience.  As Director of Research and Education at Sea Life Park, she restructured the Education Department, developed a Research Department and extensive intern and volunteer programs, and received a NOAA - John Prescott Grant.

She currently serves on the Detroit Zoological Society’s Center for Zoo Animal Welfare Advisory Committee, the American Humane Association Scientific Review Committee, the Building Ocean Awareness Together Advisory Committee, and Chair’s the International Marine Animal Trainers Association's Research and Conservation Committee where in 2011 she launched the IMATA Research Grant and IMATA Conservation Fund. Debborah earned her B.A. in Psychology from New College, the Honors College for the State of Florida. She earned her Master and Doctorate degrees in Psychology (Cognitive and Neuroscience) with a minor in Marine Biology from the University of South Florida.

Candice Dorsey, Ph.D., Director of Animal Programs

Dr. Candice Dorsey joined AZA in September 2008 as the Director of Animal Conservation. Among her responsibilities is advising and supporting AZA's Taxon Advisory Groups, Species Survival Plans, Population Management Plans, Regional Collection Plans and Studbooks. She works with the VP and Senior VP in advising animal management and conservation related board-level committees, such as the Wildlife Conservation and Management Committee, and the Animal Welfare and Field Conservation Committees. Candice acts as AZA's Conservation Endowment Fund (CEF) Science Director, and serves as a scientific liaison to other AZA departments and their programs.

Candice earned her BA in biology from St. Mary's College of Maryland and received her MS in Conservation Biology from American University, where her thesis focused on the developmental stability of the Florida manatee. She has also completed internships on Western lowland gorilla behavior, population genetics of the black footed ferret, captive giant panda foraging, and was a geneticist/technician for the Smithsonian's Natural History Museum's Department of Systematic Biology. Candice received her Doctorate in Environmental Science and Public Policy through a joint program between George Mason University and the Smithsonian National Zoo's Conservation and Research Center. Her research focused primarily on black rhinoceros health and welfare in U.S. zoos, and was partially funded by AZA's Conservation Endowment Fund.

Shelly Grow, M.S., Director of Conservation Programs

As Director of Conservation Programs at AZA, Shelly promotes and supports AZA member participation in conservation activities that directly impact animals in the wild. Shelly works closely Animal Programs, AZA members, and partner organizations.

Shelly currently manages the grants program under the Conservation Grants Fund, the Annual Report on Conservation and Science, and helps oversee AZA’s citizen science program, FrogWatch USA. Shelly has also been active on amphibian conservation issues and served as the program coordinator for the Butterfly Conservation Initiative, beginning in 2003. She received a B.A. in environmental studies from Grinnell College and an M.S. in sustainable development and conservation biology from the University of Maryland – College Park. Prior to working at AZA, Shelly worked on organic and sustainable agriculture research and policy with the US Department of Agriculture and the Henry A. Wallace Center for Agriculture and the Environment at Winrock International.

Rachel Gauza, Education Outreach Coordinator

Rachel joined AZA in 2011 with the primary responsibility of coordinating AZA’s citizen science program, FrogWatch USA. In addition to administering day-to-day activities for the program, Rachel works to expand and support its nationwide monitoring network. Rachel promotes the scientific and educational impact of the program through curriculum and resource development, chapter coordinator and volunteer recruitment and training, data management and reporting, and the incorporation of innovative online tools. Rachel also supports other conservation education initiatives to connect people to nature and instill the value of conserving wildlife and wild places.  

Rachel holds bachelor’s degrees in biology and music performance from Hood College in Frederick, Maryland. Prior to joining AZA, Rachel was a biologist specializing in monitoring and assessment of freshwater stream systems, herpetofauna, and land use best management practices. She also has extensive experience with the management and coordination of citizen science, informal education, outreach, and internship programs. Outside of AZA, Rachel supports another citizen science initiative, the Maryland Amphibian and Reptile Atlas, as a steering committee member, county coordinator, and data and verification review panel expert for the statewide effort.

Rebecca Greenberg, Program Assistant, Conservation & Science

Rebecca joined AZA’s Conservation & Science Department in October 2011. She assists with the administration of AZA’s Animal Programs, including Taxon Advisory Groups, Regional Collection Plans, Species Survival Plans, Studbooks, and Animal Care Manuals. Other responsibilities include preparing and editing reports for publication and maintaining departmental databases and records. She works closely with the Wildlife Conservation and Management Committee and corresponds with AZA members as well as the general public.

Rebecca has a Bachelor of Science degree in Psychology from the University of Georgia where she focused on animal behavior studies. She conducted original field research in Brazil on wild capuchin monkey tool-use and published her study in the journal Animal Behaviour.

Since graduation, Rebecca has volunteered, interned, and worked in the zoological and aquarium community. At Mote Marine Laboratory & Aquarium Rebecca gained experience in marine animal care, training, and conservation research, specifically working with sea turtles, nurse sharks, and manatees. Rebecca worked with Guest Programs at the Georgia Aquarium leading overnight sleepovers, behind-the-scenes tours, and assisting guests and staff during special events. She was also a husbandry volunteer with the marine mammals and penguins at the Georgia Aquarium. At Zoo Atlanta, Rebecca volunteered with the Enrichment Team where she supported zookeepers in preparing environmental enrichment for primates and other animals. She is also a former AZA Conservation & Science intern.

Government Affairs

Steve Olson, M.S., Vice President, Federal Relations

Steve became Director of Government Affairs in March 2000. The Government Affairs Department represents the interests of AZA before Congress and Federal agencies. The Department monitors Federal legislation and regulations, analyzes the impact of bills and regulations on AZA members and develops position recommendations with the Government Affairs Committee and the AZA Board of Directors, supplies information on legislation and regulations to its member institutions, and works with government officials on developing effective Federal legislation, regulations and partnerships.

Steve received his B.S. and M.S. in Wildlife Management from Colorado State University. In 1987, Steve began work for the U.S. House of Representatives' Merchant Marine and Fisheries Committee. Steve has also worked for the National Oceanic and Atmospheric Administration as the project manager for the Hawaiian Islands Humpback Whale National Marine Sanctuary and the National Coastal Resources Institute as its executive director.

Jennifer Keaton, M.A., Vice President, Congressional Affairs

Before joining the Association of Zoos and Aquariums as Vice President of Congressional Affairs, Jennifer Keaton was Legislative Director for Representative Mary Jo Kilroy (OH-15) where she supervised the legislative staff and handled issues including appropriations, health care, transportation, and foreign affairs.

From January 2001 through June 2009 Ms. Keaton worked for Representative Carolyn B. Maloney (NY-14) in several capacities including Senior Legislative Assistant and Acting Legislative Director. During her time in Representative Maloney’s office Ms. Keaton worked on several initiatives that were signed into law including “The Debbie Smith Act,” which addressed the backlog in processing DNA evidence. She also served as the Congresswoman’s staffer for the Oversight and Government Reform Committee and served as the principal staffer for the Congressional Caucus on Hellenic Issues, the Human Trafficking Caucus, and the Americans Abroad Caucus.

Ms. Keaton’s government career began in 2000 when she was hired by Representative Ron Klink (PA-04) as a Legislative Aide.

Ms. Keaton received her undergraduate degrees in Political Science and International Service and her Masters Degree in International Affairs from American University in Washington, D.C. She is a native of Pittsburgh, PA.

Member Services

Melissa Howerton, Vice President, Conferences and Membership

Melissa develops, markets and manages AZA conferences, meetings and membership recruitment efforts.

Previous to AZA, Melissa worked for 8 years at the Newspaper Association of America managing meetings, membership recruitment and retention, and committee liaison work.

Melissa has a degree in Communications from George Mason University and currently resides in Maryland with her husband, Mike and son, Cole.

Jeff Dow, Director, Sales and Marketing  

Jeff joined AZA in January 2014 and is responsible for developing and managing national marketing partnerships.  Jeff also serves as a staff liaison to the Marketing Committee.  Jeff has over 10 years experience in marketing and events and has spent previous stints with National Aquarium, National Geographic Society and the Carolina Hurricanes and Florida Panthers of the NHL. Jeff is originally from Wisconsin and currently lives in Ellicott City, Maryland with his wife, two kids, three cats, one dog, three fish and one bearded dragon.

Nette Pletcher, M.A., Director, Conservation Education

Nette develops and delivers the Association's conservation education initiatives. She promotes the role of AZA-accredited zoos and aquariums in education leadership, builds capacity for informal science education, and leads multi-institutional projects that strengthen science and environmental learning in zoos and aquariums. Nette is a staff liaison to the Conservation Education Committee and the Volunteer Management Committee and the Volunteer Management Committee. She also oversees the Association’s Professional Development Program and is a staff liaison to the Professional Development Committee. Prior to joining AZA, Nette held educator positions at the National Zoo in Washington, D.C., at the M.K. Nature Center in Boise, and at the Lincoln Park Zoo in Chicago. She has also worked as an evaluation research assistant for the Institute for Learning Innovation, and as a zookeeper for Chicago’s Brookfield Zoo.

Nette earned a B.A. in biology from Swarthmore College and a M.A. in conservation education from American University. Her master’s thesis explored the intersection of formal and informal education that occurs through collaborations between zoos and schools.

Cheryl Wallen, B.B.A., Meeting Planner

Cheryl joined AZA in January 2007. She is responsible for all the logistical aspects of the Annual Conference and Mid-Year Meeting, including registration, hotel arrangements, speaker and program management, conference webpages, and meeting schedules. She also works closely with the Conference Committee in developing programming for the Annual Conference.

Cheryl graduated from James Madison University with a B.B.A. in Hospitality and Tourism Management and a concentration in Special Events and Meeting Planning. Prior to joining AZA, Cheryl completed an internship with a corporate concierge company in Fairfax, Virginia.

Barb Skewes, Membership and Database Services Coordinator

Tim Lewthwaite, M.A., Publications and Brand Manager

Tim joined AZA as Publications Manager in September of 2004. He is responsible for producing AZA's Connect magazine and the Membership Directory. Prior to joining AZA, Tim was Director of Communications for Georgetown Preparatory School in Bethesda, MD, where he produced the alumni magazine and managed the school's Web site. He has also worked as a freelance writer and editor and has been published in Presstime, the Newspaper Association of America's magazine, Equus, a leading equestrian magazine and African Voices, a literary magazine based in New York.

Tim has a master's degree in professional writing from Towson University.

Sarah Sullivan, Digital Media Manager

Sarah Sullivan manages AZA’s digital media presence, including web, social, and new digital initiatives. She came to AZA from The Atlantic, where she was a designer for as well as working on the magazine’s mobile and iPad apps. Previously, Sarah was the web and digital media manager at the Smithsonian’s Freer and Sackler Galleries, designing and producing online features and exhibition videos and leading the galleries’ website redesign. She began her career at the American University in Cairo, Egypt, where she was publications manager for the television journalism program and managing editor of an online journal covering satellite broadcasting in the Arab world.

Sarah holds a BA in history and Arab studies from Georgetown University and a certificate of Arabic language from the American University in Cairo. She is also a volunteer at the Smithsonian’s National Zoo.

Gina Velosky, M.B.A., Manager, Business Development and Marketing

Gina’s primary focus is servicing and delivering valuable benefits to the Commercial Member category and developing sales and marketing strategies for AZA conferences, Commercial membership, and advertising. She also serves as a staff liaison to the Business Operations Committee, and the Membership Committee. Gina is a New Hampshire native with more than eight years’ experience in sales, marketing and communications in both for-profit and non-profit organizations. Most recently she held the position of Sales and Marketing Manager for the National Club Association in Washington, D.C. 

Gina holds a BA in Political Science and Government Affairs from the University of New Hampshire, and an MBA with a focus in Strategic Marketing and Analysis from Mount Saint Mary’s University in Northern Maryland. She shares a deep love of all animals and her personal passion is volunteering with dog and parrot rescue efforts.