A Blue Green Frog

Green Frog

Andrew Haydon Park is best known as a dynamic birding hotspot in the fall and early winter (before the Ottawa River freezes) when various types of shorebirds and water birds stop over on their way south. The thickets and woodlots also provide cover for migrating warblers and songbirds, and hawks patrol the water’s edge regularly looking for an easy meal. The park is not visited by birders as often in the summer, possibly because they are ranging farther afield looking for uncommon breeding birds or rarities somewhere else, possibly because the park is usually full of picnickers and children and smoking barbeques and radios playing loud music after 10:00 am.

However, first thing in the morning, before all the people arrive, the park is full of birds. Common breeding birds, true, but still birds worth seeing as they are only here four or five months of the year, and watching them feeding and raising their young is always enjoyable. Even on a bright mid-July morning there is plenty of avian activity, and today I managed to find 32 species before 10:00 am.

Families of Canada Geese were present, though the young are no longer fuzzy goslings and now look like adults. Mallards are still breeding, as evidenced by the tiny ducklings in the mouth of the creek. Robins and Blue Jays had recently fledged; the noisy young birds followed their parents around, hoping to be fed. Purple Martins and a Barn Swallow were hawking for insects, five Killdeer were either early migrants or local breeding birds, and a Rose-breasted Grosbeak, two Baltimore Orioles, and an American Redstart added colour to the trees.

My best find, however, was not a bird or even a dragonfly (and odes are another great reason for visiting Andrew Haydon Park in the summer); it was a frog sitting in the tiny channel adjacent to the island in the eastern pond. At first I didn’t even realize it was a frog; something bright turquoise-blue caught my attention, and I assumed it was some type of garbage thrown in the water. A closer look revealed it to be a Green Frog – but a blue one!

Axanthic Green Frog (Lithobates clamitans)

Once I realized what it was – and the size and dorsal ridges leave this fellow’s identity undisputed – I was thrilled. Like the famous yellow cardinal in Alabama, colour aberrations in amphibians are possible, but very rare – more rare, in fact, than leucism or albinism. Green Frogs are naturally variable in colour, but are usually some shade of green, bronze or brown. The green comes from the blue and yellow pigments of its skin; it is the absence of xanthophores, the cells in the deeper layers of the skin that contain the yellow pigment, that results in the blue colouration. This condition is called axanthism.

Axanthism has been documented in 23 species of amphibians, with the highest occurrence in family Ranidae, the true frogs; species demonstrating this condition include the Northern Leopard Frog, the Wood Frog, the American Bullfrog, the Common or European Toad, the European Tree Frog, and the Rough-skinned Newt.

Axanthic Green Frog (Lithobates clamitans)

Green Frogs are common in eastern Ontario, where they are usually found in freshwater ponds, shallow marshes, ditches and other small bodies of water that are deep enough to avoid freezing completely in the water. Normally they don’t elicit much of a response from me, unless they are sitting in a picturesque location; this one, however, was spectacular! Blue frogs – and indeed, other creatures with colour aberrations – are usually difficult to find in the wild as these very aberrations make them more visible to predators, reducing their chances of survival. As I watched, it left its exposed spot on a partially submerged tree limb and splashed across the water to a more sheltered location in the weeds. Hopefully this colourful frog will manage to avoid the herons and other frog-loving predators at Andrew Haydon Park and live out its natural life in the pond there!