Western toad tadpoles (Anaxyrus boreas) swim in Vancouver Island’s San Juan River in our Photo of the Week, submitted by clarke.kris, taken on July 31, 2011 with a Panasonic DMC-GH2. These tadpoles started life as eggs which were laid sometime in the early spring. Up to 17,000 eggs may be laid at a time and resemble ‘small black pearls laid single file’ according to B.C. Frogwatch. They quickly hatch into tadpoles, and remain this way for the summer.
In late August, the tadpoles metamorphosize into toadlets. They exit the water and head into dryer habitat such as grasslands, mostly seeking flying insects, which make up the majority of their diet. If the toadlets are not snatched up by hungry predators-such as birds, mammals, or other amphibians; afflicted with an amphibian disease such as Chytridiomycosis, an infectious fungus; or harmed by chemicals such as the fertilizer urea–than they may make it to maturity at two to three years of age. Some will even live to be 10 or 11 years old.
Western toads are found west of the Rocky Mountains, as far north as Alaska and as far south as Mexico. They are easily found in B.C. though populations are declining in the southern part of the province which is likely due to habitat destruction, disease, and invasive predators. B.C. Frogwatch states that the Western Toad is a “species of conservation concern”. In the United States, the Western toad is, unfortunately, under consideration to be classified as an endangered species-they are no longer found in much of their traditional habitat.
Let us hope that the Western toad’s classification as a ‘species of conservation concern’ in B.C. helps to protect not only the toad but also their wetland habitats. Perhaps with a little extra help, some of these tadpoles in our Photo of the Week, which hatched in 2011, are already one year into a long and insect-filled life that lasts until 2021–and beyond. Thanks to clarke.kris for sharing this photo with us.
Keep an eye out for emerging toadlets at the end of the summer–they often migrate to roads–so drive carefully!