Drawing and Learning about Fossils at Hidden Oaks Nature Center, May 6th, 13th and 20th

Photo: Courtesy of the Virginia Department of Conservation and RecreationVirginia Department of Conservation and Recreation

May 6, 13 and 20, 2023

Cost: $60.00 Sign-up through Fairfax County Park Authority
Class Code: L8Q.EJQH

7701 Royce Street
Annandale, VA, 22003

Sign-up through Fairfax County Park Authority Class Code: L8Q.EJQH

Fossils are fascinating!! Delve into the ancient world of plant, marine and dinosaur fossils by drawing fossils from the Hidden Oaks collection.  Learn how fossils form, go on a prehistoric-themed hike and try matching fossils to their ancient animal or plant. Your choice of ink pen, colored pencil, or watercolor can be used.


Drawing and Learning about Native Bees at Hidden Oaks Nature Center, April 15th and 22nd

Photo: Courtesy of the Fairfax County Government

Saturday, April 15 and 22, 2023
Cost: $40.00 Sign-up through Fairfax County Park Authority
Class Code:  LUT.90ZC

7701 Royce Street
Annandale, VA, 22003

Sign-up through Fairfax County Park Authority Class Code:  LUT.90ZC

Get to know your local, helpful, native bees!! Program includes natural history information, drawing tips, local bee identification, field sketching and walks to search for bees.


Animal Care Volunteer Needed at Hidden Oaks

Photo: Hidden Oaks, Fairfax County Park Authority

Hidden Oaks Nature Center (HONC) has an opportunity for animal lovers!

A volunteer or two are needed to help with the care of exhibit animals on Saturdays. Animals in the exhibits include turtles, toads, snakes and other small critters.

The job could be shared by 2 volunteers.  They would split up the month, each doing at least 2 Saturdays.   Because there is training involved in this volunteer opportunity, HONC is asking for a 6-month commitment.

Adults only please.  If interested, contact Avery Gunther ([email protected]) or Janet Siddle ([email protected]).

Record your hours in Better Impact as S182: FCPA Nature Center Animal Care.  In the Description field, note that you worked at Hidden Oaks Nature Center.

Naturalist volunteer opportunities at Hidden Oaks!

Photo: Hidden Oaks, Fairfax County Park Authority
Share your love of nature at Hidden Oaks Nature Center!
Hidden Oaks has opportunities for program assistants this spring.  You’ll interact with kids and families doing hands-on activities, experiments, demonstrations and crafts.
As a program assistant, you work with a staff naturalist and enhance your interpretation skills.  One volunteer is needed for each of the below programs except as noted.  To volunteer, contact Kim Young or Kari Schilling, as indicated below:

Friday, March 17, 2023
4:30-5:30PM and 7:00-8:00 pm

St. Patrick’s Day Science:

(5-12 yrs.) Come and explore some green, leprechaun science that seems like magic. We will discover what those tricky leprechauns have up their sleeves, make green snow, green slime worms, and other exciting explorations- contact [email protected]

 Sunday, March 26, 2023
1:30-2:30 pm


(5-12 yrs.) Find out what’s cracking (or not) as we do various experiments with eggs and learn about their many amazing properties—contact [email protected]

Sunday, May 21,2023
12:15-3:45 pm

DinoFest in Nature Playce:

(3-9 yrs.) Learn and explore in dinoland! Compare your height and length to that of dinosaurs. Search for hidden dinosaurs and tracks. Make a fossil impression to take home. Canceled if rain. Child must be accompanied by an adult—contact [email protected]    2-3 volunteers welcome

But that’s not all! 
You can contact Hidden Oaks Volunteer Coordinator Janet Siddle, [email protected], to connect with other programs and projects that match your interests and availability.
There is an on-going need for volunteers to help lead Hidden Oaks’ many programs and camps.  In addition, there are openings for shifts at the Visitor Information Desk.  You would be talking to the public as they enter the building, directing them to their possible interests and answering their many questions.

Hidden Oaks Renovation Plans Include Consideration for Wood Frogs’ Mating Season

Article Photos courtesy of Fairfax County Park Authority

Author Suzanne Holland is Visitor Services Manager at Hidden Oaks Nature Center.

Preparations for construction take many forms. For Hidden Oaks Nature Center, the upheaval to the trees, park access and program scheduling are but a few of the aspects that site staff have long considered to get ready for the current renovation. One consideration was the construction’s impact on the pond that many frogs and salamanders use to mate in late winter and spring. Assisted by Eagle Scout Daniel Tootle, Hidden Oaks management planned a year in advance to minimize the habitat impact – a plan that has proven to be successful over the past two weeks.

Wood frogs arrived at Hidden Oaks Nature Center’s temporary pools on Feb. 20, 2022.

The current construction required filling in the existing pond. Staff’s concern was that this would disrupt mating patterns for the frogs and later the American toads and yellow spotted salamanders. Every March, more than a hundred wood frogs gather in a small body of water just outside of Nature Playce – the site’s outdoor nature exploration area. The male wood frogs call in a laughing duck manner to woo the female wood frogs from their winter slumber. All meet up in the pond. Females lay thousands of eggs which hatch into tadpoles which metamorphose into froglets by mid-summer.

In June 2021, Dylan Tootle and 23 volunteers installed two temporary ponds on either side of the planned construction zone as part of Dylan’s Eagle Scout project. Using repurposed baby pools and prefabricated pond liners, Tootle’s “ponds” created above-ground and in-ground options for the park’s resident amphibians. The first wood frogs appeared on February 20 and soon had eggs floating in the above-ground pool in front of the building. A few days later, the second pond was brimming with frogs. While programs are currently suspended at Hidden Oaks Nature Center, the frogs and their cacophony of sound have fascinated the construction crews and contractors. Unfortunately, a dozen frogs opted to disobey the signs, hop into the construction zone and plop into the partially rainwater-filled new pond still being built. The team from Kadcon installed a ramp in the new pond to accommodate the wood frogs, who find it easier to jump in than climb out the comparatively steep sides. Though rains have created plenty of puddles over the last few weeks, the frogs seem to prefer our ponds over the rainwater puddles.

Frog mating calls joined the construction noise to create a cacophony of sound at Hidden Oaks.


Wood frog egg masses soon appeared in the baby pool pond.

The new larger and permanent pond should be ready for its new inhabitants next week. Naturalists will then relocate the egg masses and newly hatched tadpoles into their new home. Sometimes the earliest laid eggs do not survive a hard freeze, but the adults can return to their shelter under the forest’s leaves and reenter “brumation”, a partial form of hibernation. They will rouse again when the weather warms up. The staff will track which pools the frogs and salamanders prefer and look forward to sharing the marvels of metamorphosis with visitors old and young.

Hidden Oaks Nature Center is located at 7701 Royce Street in Annandale. Please note the Nature Center is closed Feb. 14 to June 10, 2022, for renovations. No public restrooms will be available until April.




This entry was posted in Resource Management and tagged construction, Hidden Oaks Nature Center, nature, outdoors, Wood Frogs on  by .

Hidden Oaks Nature Center on Your Own, Story Map a Winner!

Article by Fiona Davies, Volunteer Manager, Hidden Oaks Nature Center

Hidden Oaks Nature Center was recently awarded 3rd place in a county-wide Geographic Information Systems (GIS) competition. GIS refers to electronic maps with information attached to them. The award recognized the story map that site staff and county employees created for the 50th anniversary of the Center. A story map is an online site that tells a story using maps, pictures, and words.

Hidden Oaks actually has two story maps. The first, created for the anniversary, “Imagine the Next 50 Years,” is an evolution of the park, the building exhibits, and the surrounding areas. The second, “Habitats and Havens: Tour the Old Oak Trail” is a walking informational tour of the Old Oak Trail. The web applications are available on the Park Authority website.

“Imagine the next 50 Years” encourages viewers to consider how they can impact Hidden Oaks over the coming 50 years through learning about the last 50. The project served a twofold purpose – both communicating how the Nature Center has served the community at large and promoting the 50th anniversary event. Commercial aerial imagery supports the “Running Out of Room” section, while a photo taken from a helicopter shows the baseball fields after they were constructed. The “Expansion Through the Decades” section contains embedded web maps that users can expand to see how the park has changed from 1976 to 2019. Each section concludes with a reflection on how the next 50 years may evolve, while the app closes with a reminder that everyone can make a positive impact in their community.
“Habitats and Havens” makes a great tool for someone who lives far away or is confined to their home for some reason. For example, for grandparents so they can see and learn about the trail their grandkids walk on and ask them about it.

Both are useful to bring the past to life for young visitors who like Hidden Oaks and are interested in knowing what it used to look like. They also brings awareness to the historical and current importance of the nature center and the green space surrounding it and will hopefully spark interest in conservation and being mindful of the planet.

Story maps, technology advances nature. Do you have a story map in your future?

Drawing Winter Weeds, Nature Journaling, Feb.6th

Hidden Oaks Nature Center
7701 Royce St., Annandale VA
Thursday, 6 February 2020
7-9 pm
Cost: $15

Some flowers, ferns and grasses persist in winter as dried stalks and provide food for wildlife. Learn about local winter weeds and try drawing some from our collection. Ink pens work especially well with this subject. See a brief demonstration, then try it yourself using our collection of dried plants. A suggested list of supplies will be sent upon registration.
Code F3B.F818

To sign up use this address: or google Hidden Oaks Nature Center and click on the programs section, or call 703-222-4664.