Effects of Terrestrial Buffer Zones on Amphibians on Golf Courses

A major cause of amphibian declines worldwide is habitat destruction or alteration. Public green spaces, such as golf courses and parks, could serve as safe havens to curb the effects of habitat loss if managed in ways to bolster local amphibian communities. We reared larval Blanchard's cricket frogs (Acris blanchardi) and green frogs (Rana clamitans) in golf course ponds with and without 1 m terrestrial buffer zones, and released marked cricket frog metamorphs at the golf course ponds they were reared in. Larval survival of both species was affected by the presence of a buffer zone, with increased survival for cricket frogs and decreased survival for green frogs when reared in ponds with buffer zones. No marked cricket frog juveniles were recovered at any golf course pond in the following year, suggesting that most animals died or migrated. In a separate study, we released cricket frogs in a terrestrial pen and allowed them to choose between mown and unmown grass. Cricket frogs had a greater probability of using unmown versus mown grass. Our results suggest that incorporating buffer zones around ponds can offer suitable habitat for some amphibian species and can improve the quality of the aquatic environment for some sensitive local amphibians

Summary of Hotelling's T-squared test for Blanchard's cricket frog choice, and one-way ANOVAs for differences in relative humidity, soil moisture, insect biomass, and detection probability between mown and unmown grass.

<p>Summary of Hotelling's T-squared test for Blanchard's cricket frog choice, and one-way ANOVAs for differences in relative humidity, soil moisture, insect biomass, and detection probability between mown and unmown grass.</p

Changes in the abundance of phytoplankton in buffered and unbuffered golf course ponds over time.

<p>Shown is phytoplankton abundance (µg/L) measured in buffered and unbuffered golf course ponds from July-Sept-2008. HW =  Hueston Woods, TR =  Twin Run, OCC =  Oxford Country Club, NB =  No Buffer Zone, and B =  Buffer Zone. Error bars represent ± 1 SE.</p

Mass of green frogs and cricket frogs in buffered and unbuffered golf course ponds.

<p>Shown is mass of (A) green frog tadpoles at end of study (B) cricket frog mass at metamorphosis reared in buffered and unbuffered ponds on golf courses (OCC =  Oxford Country Club). Error bars represent one standard error of the mean.</p

Survival of green frogs and cricket frogs in buffered and unbuffered golf course ponds.

<p>Shown is survival of (A) green frog tadpoles to end of study and (B) cricket frog tadpoles to metamorphosis reared in buffered and unbuffered ponds on golf courses (OCC =  Oxford Country Club). Error bars represent one standard error of the mean.</p

Summary of nested ANOVAs for phytoplankton abundance, pH, dissolved oxygen (DO), and temperature.

<p>Summary of nested ANOVAs for phytoplankton abundance, pH, dissolved oxygen (DO), and temperature.</p

Summary of nested analyses of variance (ANOVAs) for green frog survival, mass, and developmental stage at the end of the study and Blanchard's cricket frog survival to, mass at, and days to metamorphosis.

<p>The covariate in the mass and stage/days to metamorphosis analyses is tadpole survival (Surv) for green frogs and survival (Surv) to metamorphosis for cricket frogs.</p

Habitat choice and detection rates in mown and unmown grass.

<p>Shown is (A) the proportion of juvenile Blanchard's cricket frogs choosing either mown or unmown habitat when given a choice between the two and (B) number of adult Blanchard's cricket frogs found, out of five animals, in mown and unmown grass. Error bars represent ±1 SE.</p