Don Swann
Don Swann

Sky Islands – mountains so high above the desert floor that they have their own environment – influence not only the mountains themselves but also the watersheds beneath them. The intersection of a harsh physical landscape exposed to very wet and very dry conditions, and the adaptive biological processes that result, has given rise to ecological communities unique to the Sky Islands of the desert Southwest.

Saguaro National Park’s Rincon Mountains are simultaneously influenced by rushing runoff from modern-day rainstorms and geologic events hundreds of millions of years ago.

“Rock, Flood, Fire and Ice: Life Support in a Southwestern Sky Island Watershed” will be the topic of the third Water Sustainability Seminar at the Arizona Senior Academy from 2:30 to 4:30 p.m. Wednesday (April 9).

The speakers – Don Swann, Colleen Fillipone and Chuck Perger, all with the National Park Service at Saguaro National Park – will present insights gained from more than 15 years of biological and hydrological studies that are beginning to show the relationships between the geology, water, climate, and biology in the park.

Rincon Mountains
Rincon Mountains

Key topics will include the dynamics of Rincon Creek, perennial mountainside pools locally known as tinajas, and the results of surveys of animals that depend on water, including aquatic frogs, large mammals and birds.

How can pools in the mountainside be perennial, in the midst of long-term desert heat?  Why is Rincon Creek dry except in rainy seasons, even though run-off from the mountains occurs?  What effect do the Rincon Mountains have on Rincon Valley aquifers?

Swann is a wildlife biologist who has worked on water issues at the Park for more than 15 years.  Fillipone is a hydrologist with the Park Service’s Intermountain Region providing technical assistance for 11 years.  Perger is a retiree from Raytheon who has been volunteering at the Park for the last 11 years.

Submitted  by Ted Hullar, Academy Village Volunteer

[box type=”info”] Interested in attending? Click here.[/box]
‘Fire and Ice’ – How Wet, Dry Forces Shape Watersheds: April 2014