Rewilding Earth Podcast – Episode 171: The Hidden Universe of Springs with Larry Stevens

Date: April 3, 2026
Host: Jack Humphrey (The Rewilding Institute)
Guest: Larry Stevens (Director, Spring Stewardship Institute)

Episode Overview

This episode exposes the often-overlooked ecological importance of springs—those small, perennial water sources tucked away in forests, deserts, and even the seafloor. Jack Humphrey discusses with Larry Stevens, a leading springs ecologist, the vital roles these ecosystems play, the extraordinary biodiversity they support, and the urgent need to map, study, and protect them in a rapidly changing world. The conversation blends expert knowledge, practical advice, and a call for grassroots action to uncover and safeguard the “hidden universe” of springs.

Key Discussion Points & Insights

1. Springs as Keystone Ecosystems (00:07–03:00)

• Springs as Biodiversity Hotspots: Springs serve as daily gathering points for wildlife—deer, elk, bears, mountain lions, migrating birds, and many small mammals and insects.
  • “These little patches in the landscape end up being keystone ecosystems, small, highly ecologically interactive points... point sources of biodiversity, but they're also playing a much larger role in the landscape.” — Larry Stevens (00:07)
• Unique Microhabitats: Each spring supports unique, sometimes endemic species. Example: stone flies, mayflies, and mollusks occurring only at individual springs. Springs are refuges during drought.
• Changing Conservation Paradigms: Unlike large, contiguous habitats, springs are archipelago-like, requiring a conservation model focused on many small points rather than broad swathes.
  • “This is a different kind of conservation story... where a little bit of attention can go a long way.” — Larry Stevens (03:30)

2. The Challenge: Awareness & Mapping (09:22–13:40)

• Chronic Knowledge Gaps: Most people and even conservation professionals lack basic knowledge about springs, often conflating the term “spring” with seasons or mechanics.
  • “Every lecture I give on springs, I have to spend the first couple minutes saying... we're talking about the hydrologic feature.” — Larry Stevens (09:55)
• Deplorable Mapping: Many states and countries have little or no data on their springs. Notable exceptions include Florida, Wisconsin, Nevada, and Kentucky.
• Springs’ Diversity: At least a dozen geomorphic spring types exist, each with its own unique biota – from hanging gardens to wet meadows (helicrenes) to large pools (limnocrenes).
• Recent Technological Advances: Environmental DNA and genetic studies reveal extraordinary hidden biodiversity—80+ species of amphipods and over 200 species of spring snails found in the Great Basin alone, many localized to single springs and evolving for over 12 million years.

3. The Hidden Role in Watersheds and Human Life (14:32–22:25)

• Crucial to Major Rivers: Springs provide a significant portion—up to 53%—of base flow for major rivers like the Colorado, Amazon, Mississippi, and Yangtze, yet are rarely acknowledged in hydrologic models.
  • “The Colorado river here in the Southwest, 53% of the water is groundwater... It's being fed by groundwater that's coming from springs.” — Larry Stevens (15:11)
• Economic & Cultural Significance: Springs undergird agriculture and ranching, supply bottled water (a $20–$30 billion U.S. industry), and fuel a $65 billion global hot springs resort sector.
• Endangered Freshwater Reserves: With only 0.6% of Earth’s water existing as accessible groundwater, springs represent a final stronghold—threatened by over-extraction, poor management, and ignorance.
  • “Overdrawing the groundwater is a short path to loss of ability to support human life.” — Larry Stevens (19:40)

4. Springs and Global Conservation (22:25–26:00)

• A New Global Priority: Larry and colleagues successfully advanced IUCN Motion 16, elevating springs to a global conservation concern and initiating a multidisciplinary task force to provide nations with actionable templates on mapping, assessment, and management of springs.
  • “It elevates springs to a global conservation concern... so that every nation knows what to do... that's a very bold goal.” — Larry Stevens (23:00)
• The Human Element: There are only about 250 dedicated springs conservation experts worldwide; knowledge-sharing and collaboration are critical.

5. Mapping & Citizen Science: How Listeners Can Help (26:04–38:51)

• Data Portal for Springs: The Springs Stewardship Institute has built an open data portal (https://springsdata.org) where anyone can document new springs (photos, GPS, data, history).
  • “Anybody can sign up for that database... we totally invite anybody who's interested in springs to go ahead and start their own project, start mapping springs in your area.” — Larry Stevens (26:36)
• The Mapping Gap: Many mapped springs, especially in North America, but vast holes remain—particularly in Canada, Australia, Africa, and South America.
• Discovery vs. Documentation: Some springs are truly “new finds”; others are known only locally or have never been entered into central databases.
• Deep Sea Analogues: Hot and cold-water vent springs on the seafloor function ecologically like desert springs—unique oases for strange, endemic life—now threatened by deep sea mining.
• Biodiversity Concentration: Springs concentrate plant diversity as well. In Alberta, 54 springs covered a quarter of the province's flora within 10 acres.

6. Training and Joining the Search (32:40–38:51)

• Identifying Springs: Training is available for those who want to learn how to recognize spring emergence, understand the geomorphology, and properly document findings.
  • Springs are more than just a trickle of water—often complex geomorphic and hydrologic systems with unique stream characteristics.
• Listener Action Steps:
  • Hikers and explorers are encouraged to document springs they encounter with GPS and photos, and report them to https://springsdata.org.
  • Attend Spring Stewardship Institute workshops or webinars for deeper involvement.

Notable Quotes & Memorable Moments

“Every one of those springs is visited every day by deer, elk, black bear, mountain lions, you name it. Migrating birds... can detect springs as they pass across landscapes and come in to get a drink of water. How they do that, I don't have a clue.”
— Larry Stevens (00:07)

“These little patches in the landscape end up being keystone ecosystems... They are point sources of biodiversity, but they're also playing a much larger role in the landscape. And this is a different kind of conservation story.”
— Larry Stevens (00:28)

“Most of our recent extinctions here in the Southwest, in many of the arid regions of the world, are of springs... As we just begin to learn about these things, we're seeing biodiversity levels we just haven't had any clue existed.”
— Larry Stevens (12:13)

“Springs need a PR campaign.”
— Jack Humphrey (17:57)

“Our last reserve of fresh water... overdrawing the groundwater is a short path to loss of ability to support human life.”
— Larry Stevens (19:40)

“Springs are playing just absolutely enormous and unrecognized role in our everyday lives. Understanding that when you're in the presence of a spring, you're in the presence of an interactive agent in the landscape that is playing a role, has been playing a role for time immemorial and with a little bit of care, can continue to function.”
— Larry Stevens (21:38)

“We’re now guessing it’s about between maybe 20 and 30 million springs on earth. And not just in terrestrial settings, but seafloor... Those deep sea floor springs—they're doing almost exactly what desert springs are doing—they're rich hot spots of unique life.”
— Larry Stevens (29:26)

Timestamps of Important Segments

• 00:07–03:00 – Springs as hidden, keystone ecosystems
• 09:22–13:44 – Lack of awareness, mapping gaps, astonishing hidden biodiversity, extinction crisis
• 14:32–16:15 – Springs’ role in sustaining major river systems
• 17:10–19:40 – Blind spots in policy, exploitation, and the invisible loss of vital water
• 19:40–22:25 – Economic and cultural value of springs, bottled water, agriculture
• 22:31–26:00 – Springs elevated in global conservation through IUCN Motion 16
• 26:04–31:16 – The state of global spring mapping, citizen science, and the online data portal
• 31:16–34:29 – Seafloor springs and global biodiversity connectivity
• 34:29–35:57 – Identifying and documenting springs, call to action for listeners
• 37:54–38:51 – How listeners can volunteer, train, and support springs conservation

Calls to Action & Extra Credit

• Document Springs! While hiking or exploring, take a GPS point and a photo of any spring you find; submit to https://springsdata.org.
• Join a Workshop/Webinar: Stay tuned to the Spring Stewardship Institute for training opportunities in spring assessment and monitoring.
• Spread the Word: Share knowledge about springs’ value; push for their inclusion in conservation conversations and watershed management plans.
• Support Conservation: Donations to the Spring Stewardship Institute and the Rewilding Earth Podcast fuel ongoing research and advocacy.

Final Thoughts

The episode strikes a tone of urgency, awe, and communal responsibility. Larry Stevens’s expertise and Jack Humphrey’s curiosity combine to demystify springs, recasting them from obscure features to critical linchpins of biodiversity and water security. They invite listeners to become “spring spotters,” to enrich the global database, and to champion the inclusion of springs in the world's conservation priorities.

“Springs time have come and we really, really need people to understand how important they are. And it's time to stop overlooking them, even from the conservation community.”
— Jack Humphrey (36:47)

For resources, mapping instructions, and ways to get involved, see the “Extra Credit” section at:
https://rewilding.org/podcast (Episode 171)