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Mark fallon, Director

Mark came to Briar Bush in January 2003 and became Director in 2020. He holds a BA in Zoology and French from Connecticut College. From the coasts and mountains of New England to the Rockies of Wyoming to the Delaware River, Mark has spent his professional life teaching, coaching and interpreting in the outdoors. Mark leads our talented team in all aspects of operations and projects. For 18 years as Senior Naturalist, Mark answered the public's questions about nature, taught programs, worked with volunteers, and developed a thorough knowledge of native and invasive exotics plants and horticulture. He has managed such projects as the Nature Playscape, Members' Grove and Pond restoration. Originally from Massachusetts, Mark now lives with his family in Mt. Airy, Philadelphia.

Estelle Allen, Program and Guest Services Coordinator

Estelle Allen recently joined the Briar Bush team as the Program and Guest Services Coordinator. Estelle spent 35 years at a major telecommunications company holding positions focusing on customer service and project coordination. Following retirement, she worked with the Abington Township Community Police Division providing support to the Police Athletic League, and later accepted a Customer Service position with AARP. She is committed to providing service to others, most importantly her church, The Abington Youth Aid Panel, and Montgomery County Senior Services.

Estelle lives in Glenside PA where she and her husband raised their 2 children. She cherishes the time she has with their 2 grandchildren. She enjoys family, bowling, traveling, planning, and hosting group activities for family and friends.

Will Cameron, Part-Time Educator

Will holds a Bachelor's Degree in Global Environmental Change and Sustainability from Johns Hopkins University.  He grew up in Baltimore, Maryland, heavily involved in the local scouting program and volunteering with local watershed non-profits.  His love of the outdoors was fostered while kayaking through bay grasses on the Chesapeake, backpacking sections of the Appalachian Trail, and pulling trash out of city storm drains.  Will has significant experience leading youth education and engagement programs through the Boy Scouts of America and YMCA in Maryland. He is excited to bring his talents to an organization that shares his passion for environmental stewardship and local engagement.  When he’s not at Briar Bush, Will can be found hiking on a local trail, rock climbing with some friends, or snuggling on the couch with his cat.

Melissa Eldridge, Director of Public Programs

Melissa holds a B.S. in Recreation Management and minors in Biology and Environmental Studies from Lock Haven University of Pennsylvania. Before joining the full-time education staff in 2014, Melissa had worked at Briar Bush for two summers as a Camp Counselor. Now as the Director of Public Programs, Melissa is responsible for developing and updating programs for families, senior adults, Scouts, and individuals with disabilities. She's enjoyed developing the well-received SAGE Sessions program for senior adults and the Family Nature Night program for children with autism spectrum disorder. Melissa also directs the Summer Camp program and leads some camps herself. In 2016, she received the Daisy S. Klinedinst Memorial Award for her continued dedication to expanding her involvement with environmental education in Pennsylvania from the Pennsylvania Association of Environmental Educators. Melissa considers herself a naturally curious person and a life-long learner who enjoys spending time in nature hiking, camping, kayaking, and exploring. She resides in Blue Bell with her husband, Scott.

Katie Fisk, Animal Curator and Educator

Katie has been with Briar Bush since 2009. She received her BS in wildlife biology from Colorado State University and an MS degree in Environmental Education and Interpretation from the University of Wisconsin Stevens Point. Her background consists of work with both people and animals through organizations such as the US Fish & Wildlife Service, Tampa's Lowry Park Zoo, Busch Gardens Tampa Bay, and various bird research groups. At Briar Bush, Katie loves the variety of teaching audiences of all ages and caring for the animal ambassador collection along with an amazing group of dedicated volunteers.  When not working, you might find her hiking, kayaking, working in her native garden, or volunteering at the Philadelphia Metro Wildlife Clinic.

Karen Foster, Development and Event Coordinator

Karen joined the Briar Bush team in 2016 as the weekend educator. She has a B.S. in Ecology and brought with her a combination of experiences in outdoor education, after-school and summer camp programming, curriculum development, and environmental research. Karen began collecting these experiences at Churchville Nature Center leading hikes and Lenape programs followed by time in the high desert of Las Cruces, New Mexico as part of the USDA’s environmental research program. Since then, Karen has worked with the Fairmount Park Commission, at the Schuylkill Center for Environmental Education, and on a research team at Philly U. Karen enjoys working with Briar Bush's friendly and knowledgeable staff, and has loved being a part of her local nature center, as she believes that the key to creating a healthy environment begins in your own backyard.

Ehren Gross, Senior Naturalist

An experienced educator, Ehren has been in the field of Environmental Education since 2002. Before Briar Bush, he worked in various National Parks as a Park Ranger giving talks, leading guided hikes and developing Enviro Education programs for the public. He is most comfortable in front of an audience performing live animal shows or in-classroom demonstrations. Ehren has his Bachelor's degree in Environmental Science from West Virginia Wesleyan College and a Masters in Environmental Education from Arcadia University. In his free time he loves reading nature stories, astronomy, and bush crafting. Ehren lives in Abington with his wife, daughter, family dog and colony of bees.

Heidi Malizia, Environmental Educator

Heidi holds a degree in Elementary Education with a concentration in environmental science from Penn State University. Prior to Briar Bush, Heidi taught 3rd grade for two years in a formal education setting. She loved teaching, but missed the outdoors.  After completing an internship at Shaver’s Creek Environmental Center, she was hired as the Outreach Coordinator at Great Valley Nature Center where she lead programs for all ages, and developed the Head Start into Nature Program. In addition, she ran their annual auction, taught summer camp and outdoor school programs, facilitated team building exercises, ran teacher workshops, and lead adventure trips to kayaking, camping and hiking destinations. Heidi began her journey at Briar Bush in 2009 as a part-time weekend educator, but she can be found on the property leading the Magic Mornings and Nature Pioneer preschool programs. She also travels to all 25 Montgomery County Head Starts and 14 Pre-K Counts programs twice a year, and leads adventure summer camps. Most recently, Heidi became part of the Feather Our Nest Auction and Gala development team. In her spare time, Heidi loves to be outdoors kayaking, hiking and going on adventures with her husband, three daughters and her dog.

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