Hello again! This post is all about another of my volunteering adventures with the Sheffield and Rotherham Wildlife Trust. If you read my last blog post, you’ll know I’ve been working with the National Lottery Heritage funded ‘Data for Nature’ project, which aims to improve ecological data bases for nature reserves in and around Sheffield. If you didn’t suss it from the cheesy pun in the title, my latest excursions had me on the hunt for newts. Specifically, the elusive Great Crested Newt. Over a three-month period, a handful of volunteers completed six Great Crested Newt surveys in Sheffield’s Woodhouse Washlands nature reserve. Our aims were: a) to estimate the population size of Great Crested Newts in the area, and b) to work out how suitable this site was as a newt habitat. This will help the Wildlife Trust improve and maintain the reserve so the newt population can thrive both now and in the future. Like all the ‘Data for Nature’ initiatives, these surveys help improve databases held for wild populations in the Sheffield and Rotherham area and allow the Trust to improve management of its reserves to best suit wildlife living there.
Great Crested what?
So, what actually is a newt? Newts are salamanders, which are a group of amphibians characterised by their lizard-like appearance. They have slender bodies, rounded snouts, short limbs and a tail. Unlike other members of the salamander family, newts are semi-aquatic. This means they live in both terrestrial and aquatic habitats. The Great Crested Newt is a species of newt that only lives in Europe. Females can reach 7 inches in length, making them the largest species of newt on the continent. Thanks to its prehistoric demeanour, the Great Crested Newt is often described as a mini dinosaur. They are near black in colour with bright orange bellies and spotted flanks. The males especially, with their warty skin and crinkly crest, do look like a small, slightly pathetic Stegosaurus. These warts are actually vital to the newts’ survival, as they secrete a milky rancid substance that dissuades predators. The species breeds in ponds in the spring before moving into woodlands, grasslands and hedgerows to feed on invertebrates later on in the year. We carried out our surveys in the late spring when the newts are in their aquatic breeding habitat. This made it easier to locate and count the newts. When you imagine trying to find newts in a woodland the old ‘needle in a haystack’ image comes to mind.
Other newt species…
We recorded sightings of other newt species living in Woodhouse Washlands, such as the Smooth Newt
and the Palmate Newt, though we didn’t come across many of the latter. We counted these other species of newt to see how well a variety of species are doing in the area. The Smooth Newt, also aptly known as the ‘Common’ Newt, is the species you will most likely see in your own garden or pond. They are grey-brown in colour with an orange belly and neat spots all over. Confusingly, male common newts also develop a crest during the breeding season. You can use this crest as a neat way of telling a Great Crested newt and a Smooth Newt apart: the Smooth Newt’s crest runs unbroken for the entire length of its body and tail, while the Great Crested Newt has a break in its crest where the tail and body join.
Our survey design
The Great Crested Newt is actually listed as a European Protected Species. This means that the newts, their eggs and their breeding sites are all protected by law and it is an offence to disturb them. This law dictates that a licensed ecologist must be present for any survey carried out on Great Crested Newts. To fulfil this requirement, we volunteers worked with license holders from Wildscapes Ecology. Only 2-4 volunteers helped per survey to minimise disturbance to the newts on site.
To carry out an accurate newt survey, license holders are required to collect population data in three different ways. Our three methods were: bottle trapping, torching and egg searching. Bottle trapping involves counting the number of newts caught in bottle traps set up in the ponds. As the name suggests, these ‘bottle’ traps are not the most high-tech ecological equipment…they are literally 2 litre bottles with the nozzle cut off and inverted. Crucially, however, they allow newts to swim in to the bottles but prevent them from swimming out again. We set these traps up around the perimeters of all 6 ponds surveyed at dusk. As newts are nocturnal, we had to wait until morning to see how many we’d caught. Once the traps were set, we waited (often at the pub) until sunset to complete our second method of data collection: counting the number of newts in each pond by torchlight. Using a powerful torch beam, we skimmed the bottoms of the ponds for any signs of newt activity. We didn’t get home until around midnight after this torchlight search, only to be up at the crack of dawn the next day to release our trapped newts (who needs sleep, right?). The plastic bottle traps get hot very quickly if left in the sun too long, so we had to make sure we had counted and released any trapped newts before the morning sun cooked them. Much to our delight, we found handfuls of newts in our bottle traps on those early mornings. As my friend and fellow volunteer Beth said, “at least we didn’t get up at 5am for newt.”
Our final method of data collection was to record the presence or absence of newt eggs at each pond. Newts lay their eggs on leaves around the edges of ponds. Once deposited, they nimbly fold the leaf in half to protect the tiny egg inside. Check out this fascinating photo I took of a newt embryo developing in its egg we found on site!
To assess how suitable each pond is as a Great Crested Newt habitat, volunteers completed a Habitat Suitability Index (HSI) during one of the surveys. This is a standardised method in which different aspects of pond suitability are analysed, including: pond area (m2), presence of fish and percentage macrophyte (vegetation) cover. This final aspect of the survey allowed the Trust to work out how suitable Woodhouse Washlands is as a newt habitat, so they could adapt their management of the site to maximise its ability to support a growing Great Crested Newt population in the future.
And finally…the results!
Overall, the volunteer team found some really positive results. We estimate that the population of Great Crested Newts in the Woodhouse Washlands reserve is 82 individuals – this is a really promising number! Six of the ponds on site scored ‘excellent’ in our HIS survey too. This shows us that a good number of ponds on site are already highly suitable habitats for the newts and highlights the ponds that scored lower in the HIS survey so management can work to improve these areas. Interestingly, a correlation was found between the number of great crested newts found in each pond and the HSI score. This means that ponds with higher HIS scores typically housed more newts. One pond on site was nicknamed ‘the party pond’ by volunteers as every time we emptied the bottle traps from this pond in the morning, we had caught a great number of newts. This pond turned out to be on of those that scored ‘excellent’ in the HSI survey, so it is no wonder all the newts wanted to be there to join in the party.
A volunteering oppurtunity ‘newt’ to be missed…
The newt surveys were by far the most enjoyable of the surveys I’ve been involved with for ‘Data for Nature’ so far. Despite the sleep deprivation, it was actually really good fun being out with a group of welly-booted people stood around ponds at midnight – we had a lot of laughs. It was really nice to be out in nature at dawn and dusk: the times we don’t normally get to appreciate it. Watching the sun set over the reserve was stunning, and one of the team had the good idea of bringing a bat detector so we could listen to the bats overhead in the trees. One evening, we even saw a fox patrolling the landscape. Its experiences like these that make volunteering with the Wildlife Trust so special, so get onto your local Trust’s website and find some opportunities near you.
You can learn more about ‘Data for Nature’ and volunteering here.