The FrogLog Story
Wildlife Biologist Develops a Device to Keep Frogs Out of Swimming Pools
Until the summer of 2004 I never imagined that swimming pools, the source of countless hours of childhood fun, could be so deadly for frogs and other small animals. My interest in this issue stems from personal experience brought to my attention by friends.
In June of 2004 good friends, who had recently built an in-ground swimming pool on their wooded lot near Baltimore, Maryland, called to let me know frogs were dying in their pool. Nearly every day between one and several frogs and toads were removed from their pool - some were alive but others were dead in the skimmer basket. One morning, after a warm rainy night, an astonishing 53 frogs and toads were found in the pool. I spoke with other friends with swimming pools who also said frogs are regularly found in their pools. In addition to frogs, there was the occasional mole, mouse, baby bird, opossum, turtle, salamander, squirrel, bat, chipmunk, and more.
As a wildlife biologist, I found this information troubling and decided to seek a solution. There were a few products already on the market but all had shortcomings. One product was designed to clip onto an in-pool ladder rail - unfortunately many ladder rails attach to the deck outside of the pool wall so it would not work. Another product was difficult to keep from falling into the pool. A third product was designed for larger animals, primarily pets.
I decided to build my own device. Foam and fabric material was gathered, the sewing machine was pulled out and a crude floating device with a mesh tether was constructed and placed in the pool. For the first few days we did not find any dead animals in the pool; however, we could not tell how effective the device was since there was no way to know how many animals had fallen in. To better document the efficiency of the Froglog, a funnel trap (similar to a minnow trap) was placed at the top of the device to catch all the animals that climbed up and out of the pool.
The Froglog was in the pool with the funnel trap for 23 days between August 14th and September 9th 2004. During this period, 47 American toads (Bufo americanus) and 3 green frogs (Rana clamitans) were removed alive from the funnel trap. Two dead American toads were found in the skimmer basket. During this brief test period, the Froglog was 94% effective at allowing trapped amphibians to climb out of the pool.
Since the results of this first test with the homemade Froglog were encouraging, several more were built and given to other friends with swimming pools. The feedback was positive. One Froglog user stated that she had not found one dead frog or any other small animal since installing the Froglog at the beginning of the summer. Typically she would average six frogs a week in her pool early in the season. Another user noted a drastic reduction in animals found in the pool and noted far fewer crickets were found in the pool. One user of the Froglog figured out that turning the skimmer to cycle off at night was a key factor in allowing the animals to find the Froglog before getting drawn into the skimmer.
The summers of 2004 and 2005 were spent testing and modifying the Froglog. The Froglog went on sale to the public in the late summer of 2005. A patent is pending on the device. In 2010 Swimline Corp. , a manufacturer of pool products, took over the manufacturing and distribution of the FrogLog. Our company continues to distribute the FrogLog to the public.
Our company is interested in working with the pool industry and conservation community on promoting pool owners to conserve native animals. The company is also looking to work with scientists to document and better understand this issue as little research has been done.