Image from: http://www.eol.org/pages/1019093
Common name: Northern Leopard Frog
Scientific name: Rana pipiens
Status: Special Concern (western); Not at Risk (eastern)
You may not have heard of Save the Frogs Day, which occurs in April; many people do not know about this important day. However, frogs are crucial to our survival on Earth; did you know that frogs are a sign of a healthy ecosystem? Yes, it’s true! Tadpoles consume algae and cleanse waterways, while frogs themselves eat disease-carrying insects such as mosquitoes. People tend to ignore and neglect these facts; there are now 6, 618 frog species that are threatened and over 200 have disappeared over the last few decades.
The Northern Leopard Frog is one of those 6, 618 frogs in danger. Due to rapidly depleting habitat and abnormal amounts of acid rain, the frogs’ population is decreasing quickly. However, we can stop and even reverse these effects if we educate ourselves about them and try to help them!
At a glance, the Northern Leopard Frog is an amphibian of medium size, usually brownish or greenish in colour, and ringed with leopard-like spots of black. Inside the rings of black, there is a darker green colour, thus giving it its name. They grow from 5.5 -10 cm in length, and females are slightly larger than males. Tadpole Northern Leopard Frogs are tan to dark grey, and have pale, blotchy undersides.
Northern Leopard Frogs require specific and delicate requirements: their breeding ponds must be shallow and ephemeral, and their winter ponds must be deep but not more than 60 meters in diameters, so that the frogs will not freeze. The size of a Northern Leopard Frog’s home depends on the size of the frog: bigger frogs will need a bigger range of space, whereas smaller frogs can settle in smaller areas. Their home range is up to 600 meters in length. These spotted frogs enjoy cool, moist places; popular areas for these frogs are crevices and small clearings or damp soil. They are often called Meadow Frogs, because they like grassy, open areas.
Once, these frogs populated British Columbia, Alberta, Saskatchewan and a bit of the Northwest Territories widely, but due to humans, their numbers have decreased greatly.
These amphibians have been known to eat almost everything that moves! They eat leafhoppers, voles, rattle snakes, worms, slugs, pill bugs and smaller frogs… including their younger species! To hunt, they sit and wait until a juicy meal squirms by, and then pounce from up to 45 cm away to catch their prey. Northern Leopard Frogs are both nocturnal and diurnal, meaning that they hunt during both the day and night.
Fully mature Northern Leopard Frogs meet at breeding ponds very early in spring – sometimes even before the last frost – when the water is nearing 10°C. Like many other frog species, these frogs need very specific requirements for their breeding ponds. They need to be shallow, ephemeral and exactly 10°C when the eggs are laid and hatch. The males wake first from their hibernation and travel towards the breeding ponds; there, they begin to court by calling. The females come five to seven days later and choose a mate. Mating takes place between late April and early June, taking two to seven days. Each female lays a single egg mass and leaves the pond, never to mate again. Each egg mass is typically around 1000 to 5000 eggs, though they can reach numbers of 6500 as well.
Egg masses are deposited in warm, shallow water. Babies emerge in around nine days, and, after spending a few days in the water, begin their lives as tadpoles.
Unfortunately, the Northern Leopard Frog is not faring very well as an endangered species! Deforestation, toxic rain and introduction to foreign species – such as bullfrogs and fish – are cutting this species’ chance of survival down. A huge number – millions! – died mysteriously in the 1970s, leaving scientists baffled. Fortunately, Northern Leopard Frogs are protected by British Columbia’s Wildlife Act, and conservationists and scientists are studying how to help this specie together.
1. The call of a Northern Leopard Frog can be compared to the sound of a wet hand rubbing over a taut balloon.
2. These amphibians’ mouths are so big that they can swallow garter snakes and birds whole!
3. Unlike many other frogs, this specie does not freeze solid during the winter.