Saving amphibians can start in your own backyard!

The alluring sight and sound of water in the home landscape has made water gardening one of the fastest growing segments of home gardening. Millions of people are enjoying ornamental ponds and watercourses at their homes at a time when frogs, toads, and other amphibians are facing declines due to loss of breeding habitat. Tree Walkers International has launched Operation Frog Pond to put the popularity of home water gardening to work for amphibian conservation.

The goal of Operation Frog Pond is to create high quality habitat for amphibians where they need it most by promoting the establishment of amphibian-friendly ornamental ponds and wetlands.

Characteristics of Amphibian Friendly Ponds

Amphibians live and breed in a wide variety of habitats, so there is not a single pond or wetland design that will satisfy the needs of all amphibian species or amphibians in all localities. A major objective of Operation Frog Pond is to encourage research and experimentation to develop designs and management practices to accommodate a diverse range of amphibian species with different habitat requirements. Guidelines for creating amphibian friendly habitats will be published as new information becomes available. We offer the following guidelines for creating your own amphibian haven:

Shallow Sloping Sides

While traditional water gardens are built with rather steeply sloped sides and deep shelves designed to hold marginal plants, many amphibians prefer to breed in temporary pools and relatively shallow water. Many amphibian spawning sites are in water only a few centimeters deep. Creating ponds with gently sloping sides and shallow water areas provides a variety of water depths for amphibians to seek their preferred water depth for courting and spawning.

Fish

Most traditional water gardens are stocked with brightly colored goldfish or koi and often these fish are one of the main purposes for maintaining water gardens. However, these and other large, predatory fish can be detrimental to amphibians by feeding on amphibian eggs, larvae, and even adults. Although ponds stocked with goldfish, koi, or other fish may be used by adult amphibians, it's possible that little or no successful amphibian reproduction takes place in such ponds. The widespread introduction of both native and non-native fish into historically fishless habitats is believed to be a major cause of amphibian declines in some areas. We suggest avoiding stocking amphibian ponds with fish since even small fish may prey on amphibian eggs or larvae. If mosquitoes become a problem, try experimenting with small, locally native fishes such as minnows, dace and darters which are quite beautiful in their own right and may enhance the value of the pond for wildlife conservation. Such fish are usually easily obtained with dip nets or seines with the proper permits. Always check with your local wildlife agency before capturing any wild fish. If there is potential for your frog pond to overflow into native streams (including storm sewers) during periods of heavy rain or snowmelt, then you should only stock your pond with fishes obtained from your local watershed to prevent inadvertently introducing non-native fishes into natural waterways. For more suggestions about mosquito control, see the "Mosquito Control" section below.

Pond Vegetation

Many amphibians court and spawn among emergent vegetation at the edges of pools, often attaching eggs at the bases of these plants below the water surface. Ponds that provide shallow water areas with thick tangles of vertical stems such as sedges and reeds as well as deeper areas with vegetation for attaching eggs or concealing both adults and larvae should provide a variety of suitable micro-habitats for breeding.

Surrounding Vegetation

A mix of vegetation types around the pond will likely provide habitat for the widest variety of amphibians. Some amphibians like to bask on rocks or mud banks or beneath shallow water in full sun while others prefer to remain concealed in thick vegetation or in the shade to stay cool. Providing basking rocks, shallow mud banks, and a mix of spiky and broadleaved vegetation should provide a variety of micro-habitats to suit species preferences. Of course small ponds may not allow the creation of all possible habitats around the edge. Very small ponds most likely will appeal to amphibians that live and breed in temporary pools. Surrounding the pond with uncut grasses and sedges is a good way to simulate these habitats.

Water Movement

Many amphibians prefer to live and breed in small, quiet pools or still side channels of streams and may be unable to successfully reproduce in water gardens with a current. Other amphibians only live and breed in moving water so the correct design depends on the species of amphibians you hope to attract. Placing recirculating pumps at the base of waterfalls minimizes the current created in the main pool. In contrast placing waterfalls and pumps at opposite ends of the pond creates a current that may benefit some species. In general, the species most likely to use artificial wetlands are probably those that prefer still or slowly moving water.

Mud/Silt Bottom

Traditional water gardens are typically constructed using a rubber liner such as EPDM or Polyethelyne. These materials can work well for amphibian ponds too but more and more ponds are being constructed by lining the depression with bentonite clay instead. Bentonite is a natural mineral that swells when wet and makes a nearly water tight barrier. The potential advantage of bentonite lined ponds may be that they provide a more natural substrate for amphibians to burrow into, particularly over winter. However, even rubber lined ponds can accumulate a layer of sediment at the bottom to serve the same function but the potential advantages of different liner materials is an area worth exploring.

Predators/Pets

Cats and dogs can pose a serious threat to amphibians living around artificial wetlands. These predators are particularly efficient at killing wildlife because they are always well fed and in peak condition plus they are typically confined to a rather small space where they can kill a large proportion of the resident amphibian population. It is best to keep cats and dogs excluded from artificial wetlands. Natural predators such as snakes, raccoons, and herons are a different story. Truly healthy amphibians habitats should allow amphibians to reproduce at a rate to maintain their populations while still feeding their natural predators. Creating wetland habitat that produce a surplus of amphibians that support their natural predators is a benchmark of success and should be the goal of every Operation Frog Pond participant.

Pesticides

Pesticides and amphibians don't mix, period. A wide variety of commonly used weed and insect poisons have been shown to have detrimental effects on amphibians. Chemical pesticides simply should not be used in the vicinity of amphibian ponds. Fortunately, natural plantings that are likely to produce the best amphibian habitat are also very resistant to weeds and insects once fully established. Until such areas are established, weed and insect control should be confined to mechanical and safe biological control methods.