News & Events Latest news What does a heatwave mean for amphibians? Much of Britain has been basking in glorious sunshine recently. But how do frogs, toads and newts react to an exceptional run of hot weather and no rain? It can be a mixed blessing. On the positive side, warmer temperatures in summer can help in a number of ways. Of course, as amphibians rely on external sources of heat; hot weather means they can be active more of the time. It may also mean that their prey are more active and possibly more numerous. Temperature has a crucial influence on the development of amphibian tadpoles (technically known as larvae). Essentially, warmer ponds means faster development for tadpoles. In some years when temperatures are high early in the year we’ve noticed froglets and toadlets emerging earlier from ponds at many sites. We suspect that the emergence of efts (the term for land-based young newts after they transform from larvae) will be earlier in many ponds in those years – this typically happens a couple of months later than frogs and toads. Hot weather can however also mean that ponds dry out earlier than usual. Sometimes this happens before the tadpoles have developed into young frogs, toads or newts, meaning that they perish. Although this may seem disastrous, it isn’t always bad for the population. When a pond that dries out, that can benefit amphibians in the long term as it can put a check on the build-up of predators – especially invertebrates and fish - in their breeding pond. On land, drier conditions mean that amphibians will have to search harder to find the damp, cool spots they need to take refuge. In the wild, this mix of downsides and upsides means that a single hot year probably won’t influence amphibian populations much in the long term. What can be more concerning is repeated frequency and intensity of droughts. The effect is greater when there are other factors affecting amphibians, such as habitat loss or disease. Recent research indicates that warmer weather is likely to increase the impact of ranavirosis, a disease that affects common frogs in some parts of the UK, for instance. In gardens, we understand that the overwhelming concern for many people is for the fate of their tadpoles. If the water level is getting very low, you may wish to top up your pond with water from a rainwater butt (ideally), or with tap water. When using tap water, it’s best to let it stand for a day – perhaps in a butt or other large container - before you put it into the pond, but this isn’t essential. You don’t need to completely refill the pond, as amphibian tadpoles can cope in shallow depths – 10cm (4 in) is a reasonable minimum depth. It’s also important to make sure the amphibians can easily leave the pond, as this can be a challenge in steep-sided ponds when the water level drops. Use a bit of wood, pile up rocks, or ensure there is vegetation at the edge so that amphibians can exit your pond. Of course, if you have valuable pond plants or fish in your pond, you may wish to take alternative action, but the above advice will help your amphibians. The best advice to help your frogs, toads and newts in your garden is to create and maintain high quality habitat – both ponds and on dry land. You can find out more on this by downloading our leaflet “Dragons in your garden”. Dragons in your Garden encourages gardeners to take simple steps to help out the UK's frogs, toads, newts, snakes and lizards - many of which are disappearing from the wider countryside.