The beginning of April brings the return of migratory wildlife, blossoming trees, and of course, the spawning of many amphibian and aquatic species. Our selection this week is appropriately titled “Whose Eggs are These?”. Often-times it can be difficult to identify amphibian eggs, since many of them look similar. This week, we consulted Herptologist Elke Wind to help solve our mystery. Based on the location of the photo, the size of the eggs, and the fact that the eggs are floating and seperated, she concluded that these eggs belong to the Red-Legged Frog (Rana aurora, the term ‘aurora’ means ‘dawn’ which refers to the colour of their legs).
Our selected photographer, Richard Powell, takes us into the tranquil spawning grounds of the Northern Red-Legged Frog. With great clarity, Richard captures a hopeful future for these frogs despite being labelled as an endangered species due to habitat degradation and loss, as well as competition with invasive species like the Bullfrog.
Red-legged frogs are the emblem of a healthy wetland and are the only native frog species on Vancouver Island and the Sunshine Coast. They thrive in damp, cool coastal forests near ponds or streams. During the late winter/early spring, they lay their ovum in wetlands and shallow ponds. You might never hear the mating call of the red-legged frog because males mostly make their calls underwater! Females will then lay 800-1300 eggs in a sticky cluster attached to stems of aquatic vegetation. Elke notes that as these egg masses develop, they will loosen and separate from each-other while floating closer to the surface.
The biggest threats to these iconic frogs are habitat fragmentation, removal of vegetation, pollution, and draining of wetlands; all human-induced. Along with with habitat clearing, the construction of roads and highways have fragmented their habitats which disturbs their migration and breeding patterns. Red-legged frog habitats must be protected and restored in order to replenish their populations. Edith Tobe, a participant of the 2010 Wetlands Institute in Kamloops and a partner in this year’s Sea-to-Sky Wetlands Institute, has led numerous projects in successfully restoring wildlife habitats. Last spring, Edith was restoring habitats for the red-legged frog and her inspiring story can be found here.
Their most distinct feature is the red colouring of the underside of their hind legs. It can be tricky to identify these frogs as they appear similar other types frogs and often-times identification is made based on location. Natashia Cox, a 2010/11 Wetlands Education Program intern, makes frog chasing and identification look easy as she provides a knowledgeable and fascinating insight into the world of frogs. A video of our “ribbeting” day with Natashia can be found here!
Thank you to Richard Powell for this inspiring image! If you would like to see more of his photography you can visit his Flickr Page or his website. To view our ever-growing collection of beautiful BC wetlands photographs, click here!