reptiles

What our animals are doing this month…

March 1, 2025 by Admin

Written by Emma Byrne, Transforming Lives Trainee

March is an important month for the UK’s amphibian and reptile species. The general temperature is gradually warming, and as such, many of these species are coming out of hibernation ready to breed, feed, and explore their habitats.

Amphibians:

Frogs, toads, and newts are on the move!

Common frogs and toads migrate in large numbers towards their breeding ponds, with many crossing roads in the process making projects such as Toads on Roads necessary. Male frogs can be heard croaking to attract mates, whilst spawn begins to appear in ponds. Smooth and great crested newts are also heading to the water where they perform spectacular courtship displays!

Reptiles:

The only venomous British snake, the adder, emerges from hibernation as days lengthen. Males have been observed lying out in the sun, a behaviour that allows them to build up energy before shedding skin prior to breeding season. Other reptiles, such as grass snakes and slow worms, also awaken but bide their time waiting for even warmer weather to descend.

March is the perfect month to get outside and begin looking for amphibians and reptiles in the wild! If you happen to see any, please register your sighting on our free Froglife Dragon Finder App.

What our animals are doing this month

February 1, 2025 by Admin

Written by Charles Bonnett, Transforming Lives Trainee

It’s February and we’re settling into the New Year. For our animals, February can represent a period of transition, as the first signs of spring start to stir them from their dormancy.

For some amphibians, February marks the beginning of their habitual migration to their breeding ponds. Male common frogs typically arrive first, ready to attract females. In warmer, southernly regions of the country, mating may have already occurred by late February and frogspawn may be present. Likewise, during warm, wet evenings, common toads will begin their migration to their ancestral breeding ponds; these epic journeys can sometimes span kilometres. Some of our three native newt species, smooth, palmate, and great crested newts, will similarly begin to rouse from their dormancy, though will likely remain more inconspicuous than their frog and toad counterparts.

In comparison to amphibians, our reptiles are more temperature-sensitive, and so will mostly maintain their dormant state throughout the cold February days in order conserve their energy. Though, this does not mean that reptiles will be completely inactive during this period; a warm spell may stir adders and common lizards from their inactivity, after which they may be seen basking on south-facing slopes to regulate their body temperature in preparation for spring.

Generally, there is a degree of variation in when a member of a species may exit brumation, in part influenced by regional variation in weather, where earlier activity may be observed in more southerly regions. A further notable impact on this transition is our ever-changing climate. Our winters are becoming milder and less predictable, leading to our amphibians and reptiles exiting their dormant state prematurely. This early emergence can be dangerous, as it can leave the animals exposed to unpredictable weather, such as cold snaps. Likewise, it can cause the expenditure of energy during colder periods which may be difficult to recoup as sources of food will be rarer.

Overall, then, February can be a transitionary period from dormancy to activity for our amphibians and reptiles, and will likely continue to be with greater frequency due to our changing climate.

Remember to report any sightings of our species (including eggs and young) on our free Dragon Finder app.

Impact of basking banks on UK reptiles

December 17, 2024 by Admin

A new study by The University of Reading and Froglife highlights the impact of constructing Basking Banks on four UK reptile species and the implications for reserve management.

Researchers studying reptiles as part of a long-term monitoring programme found that in the 12 months after constructing basking banks only viviparous lizards were observed near them. However, in subsequent years, barred grass snakes increased near the banks and slow worms were observed for the first time. In nearby areas (approx. 100m away) with no basking bank construction, European adder observations increased and barred grass snake observations decreased. The basking banks created in this study were north-south facing, maximising their potential for thermoregulation, and were also full of holes and crevices that may be attractive to reptiles for predator avoidance.

_{In subsequent years of the basking banks being constructed, barred grass snakes increased near the banks and slow worms were observed for the first time.}

“This is an interesting finding because it suggests the simple practical action of building basking banks can enhance local reptile diversity. We think reptiles probably used the banks even more extensively than was recorded, as they are good places to hide from researchers.” Dr Brian Pickles, University of Reading.

The study was conducted as a part of a long-term partnership between Froglife and The University of Reading and contributes towards Froglife’s commitment to testing one habitat management intervention per year. Froglife is an ambassador for The University of Cambridge’s “Conservation Evidence” project and this research will add to the available evidence on actions to support reptile conservation in the UK, which is currently very limited.

“It’s essential that we take action to protect reptiles in the UK; we hope that this study will inspire members of the public to get involved in reptile monitoring schemes, and also inspire site managers to set up similar surveys and manage habitats for the benefit of reptiles as well as other species.” Jenny Tse-Leon, Head of Conservation and Impact at Froglife.

The UK has six native reptile species, and all are legally protected by the Wildlife and Countryside Act (1981) and section 41 of the Natural Environment and Rural Communities Act (2006). Despite this, reptiles are the least recorded vertebrate taxon making population trends difficult to obtain for most reptile species, even the most common ones. Globally, the need for improved conservation action to tackle reptile declines is gaining wider recognition.

In Feb 2019 basking banks were created by Froglife with the goal of expanding the favourable habitat for the European adder and hopefully increasing their local population. Each bank replaced a patch of grass with a raised area of rock, brick, and bare earth with a roughly flat rectangular centre (approx. 1 x 2 m) and the longest sides facing north/south at a height of ~50 cm with ~45^o downward slope. Coupled with a long-term reptile monitoring programme at the site, this enabled a 5-year before-after control-intervention study of the impact of basking bank creation on habitat use by four co-occurring UK reptile species: European adder (Vipera berus), barred grass snake (Natrix helvetica), slow worm (Anguis fragilis), and viviparous lizard (Zootoca vivipara).

_{This small-scale study shows the utility and importance of performing reptile monitoring before as well as after management interventions.}

Interestingly, while the intervention was targeted at European adders, the researchers found that adder numbers increased in the wider area rather than directly around the basking banks. The banks themselves became important for barred grass snakes on the site. This small-scale study shows the utility and importance of performing reptile monitoring before as well as after management interventions, and the authors suggest that similar studies would benefit from directly monitoring reptile use inside the basking banks where possible. Adding basking banks appears to be a low-cost intervention with benefits for local reptile populations that can be carried out with small teams of volunteers, so it could be a useful addition to charities and site managers operating with small budgets.

You can read the full paper here.

Sand Lizards

November 1, 2024 by Admin

Written by Eve Goddard, Transforming Lives Trainee

Sand lizards (Lacerta agilis) are among the most fascinating reptiles found in the UK. Known for their striking appearance, males are particularly vibrant during the breeding season, sporting bright green flanks, while females and juveniles display a more muted brown and green palette, perfect for camouflage in their sandy habitats!

These lizards predominantly inhabit sandy heathlands and coastal dunes, making them an essential part of these fragile ecosystems. They thrive in warm, dry conditions where they can bask in the sun, which is crucial for their metabolic processes. Sand lizards feed on insects such as spiders, beetles, and ants. Their hunting technique involves a combination of stealth and quick strikes, demonstrating their agility and speed.

Mating typically occurs in spring, and females lay clutches of 5 to 12 eggs in the summer. These eggs are buried in loose sand, where they incubate for around 8 to 10 weeks. The hatchlings emerge in late summer, often facing a tough start as they must avoid numerous predators, including birds and larger reptiles.

Despite their resilience, sand lizards face significant threats in the UK. Habitat loss due to urban development, agricultural expansion, and changes in land use have severely impacted their populations. Additionally, climate change poses a further risk by altering the delicate ecosystems they depend on. Burgeoning deer populations also pose a threat due to the rise in the number of ticks. In their early growth stages, ticks feed on sand lizards. A large infestation of ticks can be detrimental for a sand lizard with a compromised immune system or when trying to build strength and size for the winter hibernation.

Conservation efforts are critical to ensuring their survival, with various organizations actively working to protect and restore their habitats. Designated sites like nature reserves play a vital role in providing safe environments for these reptiles to thrive.

In recent years, reintroduction projects have also been implemented in areas where sand lizards have vanished. These initiatives aim to bolster existing populations and restore genetic diversity.

How can you help sand lizard conservation? Well, knowledge is power in conservation! If you spot a sand lizard, record your findings on our Dragon Finder App to help us to continue to monitor existing populations and contribute to nationwide conservation efforts.

Reptiles and Amphibians in Winter: #WinterWildGardening

October 22, 2024 by Admin

Winter is traditionally a quieter time in the garden, but this is in fact the busiest time of year for habitat management for reptiles and amphibians. As the temperature drops, these animals become dormant, making it safer to clear out ponds and build shelters causing as little disturbance as possible.

For our winter campaign #WinterWildGardening, we have put together some tips and tricks on how you can make our species lives a little bit easier in your gardens and green spaces.

How to tackle icy ponds:

If you have a garden pond, the colder weather can cause it to freeze. The best thing to do is to periodically sweep away any snow so that sunlight can reach your pond plants and produce oxygen. This will help to prevent ‘Winterkill’ which is caused by toxic gases released in the pond (through natural decomposition of dead leaves) and not being able to escape, causing the water to become deoxygenated.

Melting a hole in the ice won’t necessarily affect the amount of oxygen diffusing into the water, but there is no harm in playing it safe! You can gently melt any ice with a cup or pan full of hot water to allow more active animals like newts to move to the surface to breathe.

You can also try floating a small object, e.g., a tennis ball, in the water or keep your fountain going (if you have one) to prevent ice formation.

If you have frog spawn, the upper portions may freeze, but the spawn that is underwater should survive. However, if you have a very small pond and/or it is shallow and prone to freezing throughout, you can temporarily place your frog spawn into a bucket of pond water and place in a garage, or similar place, out of the freezing conditions.

Remember that moving spawn to other ponds risks spreading disease, so once the cold weather has passed, ensure that you return the spawn to the same pond to allow it to continue to develop.

Creating overwintering sites:

Something as simple as a pile of leaves or areas of dense vegetation and scrub close to your garden pond will provide areas for amphibians to take refuge during periods of cold weather.

Log piles and rockeries are another simple idea to provide our species with somewhere to see out the winter months. As well as providing cover from adverse weather, dead wood attracts insects on which reptiles and amphibians will feed.

If you want to go further, you can build a hibernaculum. You can find instructions on how to do this here.

If you don’t have space to create a hibernaculum, you could consider a toad home. These can be made simply by upturning a plant pot and knocking a hole in the side for a door. Place old leaves or grass inside your toad home for extra protection. You can find instructions on how to build one here.

What to do if you disturb a reptile or amphibian during winter:

Reptiles and amphibians lie dormant during the coldest months but will take advantage of milder patches of weather to come out and forage. For this reason, if you do disturb an animal in winter, it should be unharmed if covered up and left undisturbed.

If you are unable to put the animal back where you found it, place it somewhere that offers protection from frost and predators like cats and birds, for example, log piles, under a shed or within your compost heap. It should not be somewhere ‘warm’, just a place that is frost free.

If you spot any of our species out and about, please remember to record them on our free Dragon Finder App. Data from the Dragon Finder App is crucial going forward to monitor the relationship between temperature changes and the behaviours of reptiles and amphibians in the UK.

If you spot any sick or injured reptiles or amphibians, please report them to our partners at the Garden Wildlife Health project.

Further Resources:

For more information on how you can help reptiles and amphibians during winter, check out….

Pond Maintenance
How-to guides (hibernaculum, toad homes etc.)
Frequently Asked Questions

New Adder genetics study: implications for Conservation

October 2, 2024 by Admin

Written by Jenny Tse-Leon, Head of Conservation & Impact, Froglife

adder A new study published today by ZSL’s Institute of Zoology, the University of Cambridge and Froglife highlights important implications for conservation of translocating adders.

Researchers studying an adder population in eastern England found that a population formed by the release of seven individuals managed to establish a population despite low genetic diversity – although there may have been an additional, unlicenced translocation at a later date. DNA samples found the genetic signature of the translocated snakes in the population, indicating that the translocation has been successful over the long term. However, there was also evidence of reduced genetic diversity, likely due to the small number of animals involved in the translocation.

The study was initiated after the 2015 discovery of a stillborn clutch of five adders still in their amniotic sac, raising the question of inbreeding in the population. Genetics samples of the stillborn clutch were collected as part of the Garden Wildlife Health project, a national wildlife disease surveillance scheme.

Analysis found that the clutch sampled was likely fathered by more than one male. However, the reasons behind stillbirth could still be genetic, as well as environmental maternal effects.

Despite being given some protection by the Wildlife and Countryside Act, adders can still be moved to new sites (translocated) without the need for this to be recorded or monitored – meaning very little is known about its impacts on adders. The population in this study was known to come from the introduction of seven adders from a development site 20km away, eighteen years previously, to a reserve now managed by Froglife. This provided a rare opportunity to study the impacts of a small translocation on the resulting population – making it one of few, long-term genetic based studies following an adder translocation.

Adder populations in the UK are severely declining, particularly small populations, due to habitat loss, habitat fragmentation, human disturbance and consequentially inbreeding as populations become increasingly isolated. While misconceptions about adders have led to their persecution, these snakes are not dangerous if left alone and are an important and culturally relevant part of the UK’s natural heritage.

Professor Trent Garner, researcher as ZSL’s Institute of Zoology said: “Adders are declining in numbers across Western Europe, and we need a better understanding how translocations could be used to reverse these declines and restore their numbers. Population genetics can be used to understand the more long term outcomes of translocations in terms of reproduction and population growth. Careful management and ongoing monitoring are key to ensuring future populations are genetically healthy and able to grow and flourish.”

Since managing the reserve, Froglife has carried out annual reptile surveys showing a supposedly healthy and likely expanding population resulting from this translocation. This study found however that the adder population has a low genetic diversity in comparison with published data from similar sized adder populations which is typical for a bottleneck in the population history. The cause of the stillbirth clutch might have been a result of maternal fitness, which could either be a result of inbreeding or another factor such as disturbance from dog walkers, mountain bikers and trampling of vegetation. Whatever the reason, female adders often have only one litter in their lifetime, so the loss of the whole clutch can have a significant genetic and demographic impact on a population, especially an isolated population with low genetic diversity. In this study the loss of four females in the clutch is significant in a population already showing a relatively low proportions of females. It highlights the need for protection of small populations in particular and ensuring connectivity between different populations.

“The discovery of a clutch of stillborn adders was very worrying however the outcomes of the research are reassuring for this population. The study shows the value of long-term monitoring and the need for ongoing funding to enable this to happen. It would also not have been possible without the support of our committed volunteers.” Jenny Tse-Leon, Head of Conservation and Impact at Froglife.

reptiles

How to tackle icy ponds:

Creating overwintering sites:

What to do if you disturb a reptile or amphibian during winter:

Further Resources:

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