February

Frogspawn

Depending on the weather and how warm the temperatures are, February normally sees the first frogspawn appear in our ponds and ditches showing us that spring is, hopefully, only just around the corner.  So, where have these frogs spent the winter? Well, the answer is that frogs hibernate in all sorts of places, some choosing the mud in the bottom of the pond, others preferring to find places such as log piles, under garden sheds or in cavities within stone walls. Frogs are really only reliant on water to breed, spending most of their adult life stomping (or should I say jumping) around the countryside!

This was very much brought home to me when I came across a frog in a wood, miles from any water - or so I thought! I later discovered frogspawn in some ruts that the forestry workers’ machinery had left behind. Some years these ruts hold water long enough to raise froglets, but in others they dry out, killing all the tadpoles long before they are old enough to survive out of water. As long as there is a successful breeding season every now and again to replenish the local population, it appears that these woodland frogs are doing all right.

When people put in a garden pond, they are often eager to fill it immediately with plants, bring in frogspawn and put the obligatory goldfish or two into it. That’s one way of course, but it is also fascinating to observe how quickly wildlife will colonise the new pond without a helping hand. I would probably simply buy a couple of oxygenating plants from a reputable garden centre (put the wrong, invasive plant in and you will forever be trying to get rid of it!) and sit back to watch the way it evolves. You are quite likely to get frogspawn in the first spring, maybe newts and almost certainly dragonflies!

If you want a “wildlife” pond, try and create lots of “edge” by having an irregular shape to the pond and also make sure that there is plenty of shallow water as this is what many creatures look for – including frogs to lay spawn in. Somewhere around the pond, make the edge level with the water so that it is easy to get in and, importantly, out of the pond. If you put fish into the pond, don’t expect too many frogs, newts, dragonflies or indeed other wildlife, as most fish will hoover up all the eggs and young, well before they reach maturity.

A frog may lay between 3 and 4 thousand eggs which, once the jelly that surrounds them has swollen with the pond water, can look rather a lot for a small pond! But remember that only between 1-5% of these eggs will go on to produce adult frogs, the others dying or being predated by a wide range of hungry mouths. Because in some parts of the country there is a virus that frogs get, it is perhaps not advisable to move spawn between ponds, as you may inadvertently be “infecting” a pond by spreading the virus.

Once the eggs hatch, the tadpoles spend about three months metamorphosing into tiny little frogs. Then they will leave the pond, often on a warm, wet, rainy night so that in the morning the garden suddenly seems to be full of miniature froglets, which maybe where the origin of the saying “it’s raining frogs” comes from!

Peter Thompson
Advisory