Cosy and warm

John Beech – Land Management Adviser

Hygge (pronounced hoo–gah) has been a major trend for this Christmas period. It’s a Danish ‘concept’ of living cosily e.g. wearing thick socks whilst drinking hot chocolate and watching Murder She Wrote – which can make us feel better about the icy and harsh season outside.

For a number of wild animal species, they have their own version of hygge except for them it’s a necessary survival mechanism. Hibernation is an extended period of deep sleep, or torpor*, which allows animals to survive the winter extremes. By reducing their metabolic rate and lowering body temperature this enables them to sit tight, conserve their energy and survive through the cold periods when food is scarce or has little energy value. *Animals in a state of torpor rather than sleep can venture out to try and find additional supplies during warmer winter spells.

In autumn as the temperature begins to fall and the nights draw in, many of the small mammals that live in our fields, woodlands and hedgerows forage for extra food to store over the winter and look for a suitable site (a hibernaculum) to hole up in for the coldest part of the year. Autumn months are often one of the better times of year to see small mammals in the North York Moors such as mice, voles, shrews and Hedgehogs (Erinaceus europaeus) out and about eating vast quantities of food to build up fat reserves which will carry them through to the spring.  Following this period of feasting they retreat to somewhere suitably warm and undisturbed and begin to enter into a period of hibernation, which can last for up to four months of the year depending on the harshness of the weather. Also in autumn bats relocate to hibernation roosts looking for a constant temperature and to avoid frosts and freezing e.g. caves, trees and built structures.

And it’s not just our small mammals that hibernate:  Queen bees dig in for the winter and also some species of moths and butterflies, like the Duke of Burgundy (Hamearis lucina) which hunker down in grassy tussocks. Many of our reptiles and amphibians also hibernate. Adders find warmer crevices under boulders or in dry stone walls. Newt species spend the winter in the muddy banks of ponds, under paving slabs, piles of wood or in a handy compost heap. Common Toads (Bufo bufo) sleep out the winter buried deep in damp places such as leaf piles or compost heaps, before emerging to travel back to their traditional breeding sites in early spring. The Common Frog (Rana temporaria) which needs to keep damp is able to partially freeze in its state of hibernation before thawing out in spring. Occasionally such species come out of hibernation during any short sunny spells in the winter to make the most of the weak sunshine, only to return to their hiding place when the temperature falls again.

Malkin Bower, Bilsdale - in winter - copyright NYMNPA.

So as you’re reading this, hopefully somewhere cosy and warm, spare a thought for our wildlife that’s out there sleeping through the winter, hidden away from view deep in their retreats, practising their own life saving hygge and waiting for the first signs of spring.

Giving toads a fair chance

Some thoughts from Steve Rogers of the Osmotherley Toad Patrol

The Cod Beck Reservoir site, close to the village of Osmotherley, is one of Froglife‘s top ten toad breeding sites in the UK. The aim of the Osmotherley Toad Patrol every February/March/April is to make sure as many toads as possible get safely across the nearby main road and to and from the Reservoir.

Common toad (Bufo bufo) - by Steve Ratcliffe, from BBC website http://www.bbc.co.uk/nature/life/Common_Toad

Question: What has been the impact of toad patrols on the population of toads around Cod Beck Reservoir? 

Conclusive evidence cannot be drawn, one way or the other, from the available data.  There are just too many other variables* to consider.

Cumulative Toad Numbers 2002-2014 - Osmotherley Toad PatrolThere were significant increases in toad numbers for 2002-2003 (when the organised patrols started), 2004-2005 and 2009-2010 but whether these were due to the patrolling …. Steve cannot say. The best year for numbers so far was 2005.

However it’s difficult to envisage how toad patrols could conceivably damage toad breeding success. Steve and others believe that toads migrate quite large distances, maybe over several days, across the North York Moors from their summer residences/hibernation sites. The patrols only work on the road side of the reservoir and it is quite possible that similar numbers come directly off the Moors or out of the moor edge woodland on the non-road side. The patrols are helping the toads move the few final hazardous – because of the unnatural predation by vehicles – metres to enter (or exit) the water. In addition, the patrols are helping to bring males and females into contact ready to breed by collecting them in numbers in their transport buckets.

As for other amphibians…frog numbers have been declining significantly both nationally and locally, possibly due to disease – “red leg” (Bacillus hydrophilus fuscus) and Chytrid fungus (Batrachochytrium). The patrols have not seen direct evidence of either disease, except possibly one or two specimens.  However, frogs are moving before toads and the toad patrols really get going, in the coldest wettest nights of late February, so can’t report with any certainty on the frequency of frog disease. The patrols sometimes come across newts, probably Palmate. Numbers of newts have fluctuated greatly and may also have been affected more recently by Chytrid.

Toad numbers - Osmotherley Toad Patrol since 2002

*Variables

The trends in toad numbers are difficult to assess because of the multiple variables involved.

Weather

Over the last 10 years or so patrols have experienced a series of very cold, often dry spring conditions. Toads generally do not move if the temperature is below about 8C (though if it has been warm during the day they may move briefly at dusk with the temperature as low as 4 or 5 C). During a “normal” spring this threshold is reached around mid-March. What has happened in several years is that migration has begun in a brief period during mid-March but then the weather has turned colder for several weeks and stopped any movement. This makes it very difficult to forecast when it will be worth patrolling and, indeed, to keep volunteers motivated. Extreme cold conditions prevailed in 2013 when temperatures did not become suitable for migration until mid-April. A further feature worth noting is that, when toad migration has been inhibited by low temperatures for several weeks, movements also occur during daylight hours when it has been warmer. Of course, with higher traffic volumes during the day when people like toads come out to enjoy the warmth the numbers of toad casualties are greatly increased (e.g. 2007, 2011 and 2012). In 2005 – the best year – there was a consistently mild spring and all movements took place over a couple of weeks.

Diligence of patrols

During the first few years of patrols there were very adequate numbers of volunteers, and patrols were admirably thorough. As years have gone by the numbers of volunteers decreased to a very few until 2014 when Steve launched a publicity/recruitment drive. The new volunteers along with the remaining core were extremely diligent and the patrols achieved their lowest mortality rate since the heydays of 2005. It remains to be seen if adequate numbers of volunteers for 2015 turn out…

Other factors

  • 2001 The pernicious outbreak of Foot and Mouth disease lead to complete closure of the road during the toad migration period.  This was obviously good for toads, and may explain why the start of formal patrols in 2002 found large numbers.
  • 2004 A large wild fire in March on National Trust moorland (to the west of the reservoir) led to the inevitable discovery of incinerated toads. This may explain the drop in numbers compared with the previous year, though the following year (2005) was an all-time peak (7,325 toads).
  • 2009 A major emergency services rescue operation occurred in April. The night was mild and wet encouraging toad movement. The number of vehicles involved unfortunately led to a high level of accidental mortality amongst the toads.
  • 2011 onwards – Cod Beck Reservoir (Yorkshire Water owned) was partly drained in order to carry out maintenance work on the dam. Water levels were several metres lower than normal and it is supposed that this greatly affected breeding success as toads breed in deep water. The following year was the absolute nadir in toad numbers being a factor of 2 lower than any other year. Numbers have not recovered to pre-2011 levels since. There is some uncertainty around the future of the Reservoir and therefore the future of this toad breeding site.

The patrols out of Osmotherley will be setting forth again in the next few weeks – all volunteers are welcome. Click here to sign up.

 An information evening for those interested in helping out with the Osmotherley Toad Patrol is being held at the Queen Catherine Hotel in Osmotherley on Wednesday 18 February at 7.30 pm.

Swallows and Amphibians (and ponies)

John Beech – Heritage Coast Project Officer

The six ponds installed last year through our Habitat Connectivity programme (“Linking Landscapes”) are thriving with life this spring. I’ve just returned from a site visit to the area north of Robin Hood’s Bay and found the ponds full of tadpoles, water boatmen, backswimmers and whirligig beetles. It’s a marvellous sight given that these shallow hollows in the landscape previously held no water at all and contained very little in the way of wildlife.

We arranged the project with the landowner (National Trust) and tenant, and paid for the contractor with his mini digger to form these scrapes and ponds. The ponds were fenced off to allow the vegetation around them to grow up and not be grazed off by stock. This type of habitat should be ideal as breeding sites for amphibians.

Whilst looking for submerged wildlife, I also saw my first Swallow of the year as it swooped to drink from the ponds freshwater after its long journey of migration. The Yorkshire Coast must have been its first landfall for thousands of miles. It’s incredibly satisfying to think that you’ve added to the whole biodiversity and wildlife interest of the area with a few scoops from a digger.

Further up the coast at Wrack Hills near Runswick Bay, hardy Exmoor ponies are settling in well on the undercliff grassland. Undercliff habitat is found alongside soft cliffs where the land has slumped and settled, and been recolonized by vegetation over time. During the winter we’ve fenced off part of the existing SSSI (Site of Special Scientific Interest) and installed a watering point. The fencing, in part, follows an historic fence line which implies that there was stock in the past on this useful, if difficult to access, rough pasture. We were previously talking about putting cattle on the undercliff but instead the land manager has managed to arrange for Exmoors to begin to tackle the coarse grasses and scrub that have been taking over the site. This conservation grazing regime is aimed at halting the decline of the patches of species rich grassland that are left here. Big thanks to the land manager and the Exmoor Pony Trust for taking on this challenge. We’re promoting this type of grazing management on the National Park’s coastal undercliffs wherever possible.

The two ponies (one small mare and one larger gelding) were introduced to the site in April. Since then the paths they’ve made (and dung piles they’ve left!) show that they’ve explored much of the site and have started to make an impact on some patches of grassland. Encouragingly there are plenty of primroses, bluebells and a few early-purple orchids in flower, so it doesn’t look like the ponies are eating the flower heads.P1030889

It might be good to have more ponies on the undercliff when the ground is drier and less liable to poaching up. Otherwise combining ponies with the land manager’s own shorthorn cattle might be advantageous. Mixes of ponies and cattle have an added benefit that ponies can graze the best grass very tightly, which encourages cattle to tackle the rough stuff before the ponies might get round to it. In addition, after the bird breeding season, if human labour is available, it might be worth strimming some of the edges of the bramble patches, or creating routes though them which the ponies can then expand. The same could apply to bracken patches, although I hope the ponies might make inroads there themselves.

Toad patrolling

Bill Shaw – Ecology and Conservation Land Management Adviser

For us ‘herp enthusiasts’ (people who love amphibians and reptiles) this is a very exciting time of year. After 5 months of twiddling our thumbs, when all 13 of our native ‘herp’ species are hibernating, there is now a big build-up in the amount of activity as they are all frantic to breed!

In the amphibian world frogs hibernate under the mud at the bottom of ponds, absorbing sufficient oxygen through their skin to survive. They are the first to wake up and start spawning, generally in February. They are described as being explosive breeders as they cause quite a commotion in their breeding ponds for a week or two, with many croaking males visible at the surface.

Then it all goes quiet.

Well, at least until the common toads get going!

These endearing creatures (personal opinion) hibernate on land and then in March they move en masse to their breeding ponds, which is often the one they were born in. If there is a road to cross on the way there is the obvious potential for a lot of squashed toads, and this is where the organisation Froglife have stepped in to co-ordinate a national scheme of Toad Patrols. Last year it’s estimated that they helped nearly 81,000 toads to safely reach their home ponds.

One such patrol site is near Osmotherley, on the western edge of the National Park. I went up there a couple of weeks back to help out and what a satisfying thing it is to do. All you need is a bucket, a torch and a high-vis jacket and away you go, walking up and down the road in the dark, putting the toads in the bucket and taking them to the pond. The thing I really liked about it is the direct connection with nature. Just think about it – how often do you actually get to pick up any wild animal.About to set off across the road (female toad with male on its back)Setting off across the dark dangerous tarmacSafely arrived

 

 

 

 

More encounters

Sam Jones – River Esk Project Student

I was thinking about what I could share with you and found myself pondering the various enchanting and unexpected meetings I have had with wildlife since starting here in August. I decided to ask around the Conservation Department and gather together a number of recent stories and the odd picture to share.

It is amazing once you stand still how quickly wildlife often finds you. Whilst carrying out the Veteran Tree survey in Hawnby, Alasdair and Alex have been lucky enough to have several great wildlife encounters. While standing still, quietly surveying a fantastic old oak tree with lots of veteran characteristics a tiny Goldcrest started calling close by, this lovely wee bird was shortly followed by a flock of Long-tailed tits, chattering loudly in the canopy above them. They then heard the recognisable sound of a wood pecker drilling into old dead wood…to their surprise it was a rare Lesser spotted woodpecker, the first time either of them had seen one. It was surprisingly small compared to the more commonly seen Great spotted woodpecker and busied around for a good 10 minutes. They enjoyed watching it so much that neither of them thought to take a photo!

Whilst out conducting botanical surveys for the National Park’s habitat connectivity ‘Linking Landscapes‘ programme, Kirsty, Ami and Alex found some interesting creatures in the undergrowth.

Minature worldAlex and Kirsty joined in with a bunch of volunteers to discover how to spot water vole signs around Fylingdales, and although they didn’t see any notoriously shy water voles, there was a female adder lurking nearby.

Female adder

As well as adders, beautiful slow worms can often be found under stones, in and around dry stone walls, like this one found in a derelict wall near Cawthorn Camps.

Slow worm - being moved for it's own safety

Talking about Cawthorn Camps – from time to time, one of the tasks for Graham, our Senior Archaeological Conservation Officer, is to keep an eye on the Roman forts here. The site is owned and managed by the National Park Authority and Graham is watching out for erosion and encroaching vegetation problems. On a particularly hot, sunny summer’s day, he was showing a placement student around the site. Many of the visitors to Cawthorn walk around the main circular path, often exercising their dogs, but the interiors of the forts at this time of year are covered in long grasses and some heather. Because few people venture into the fort interiors, they are well-known as good adder habitat. In this sort of knee deep vegetation, generally the first sign of the presence of an adder is a fierce hiss just before you are about to step on it! On this most memorable occasion, Graham was pointing out the subtle internal earthworks of the site to the student when an extra loud hiss sent him into low earth orbit, badly jarring a frozen shoulder at the time – excruciating! He landed – unfortunately without a camera to hand – to the sight of a pair of conjoined adders which then – their coitus interrupted – serenely slid away while Graham + student stood there, recovering from the shock.

An excited Simon during his second summer of surveys for the Esk Pearl Mussel and Salmon Recovery Project found a “young” pearl mussel. Until then he had only found mussels which were 60-70+ years of age. This individual – the smallest live musseI that has been found in the river (75mm) recently, was approximately 20-25 years old. This proves that the mussels have bred successfully in the not so distant past, which gives encouragement to the aims of the Project, and all in all it was Simon’s best day out – ever.

A young Freshwater Pearl Mussel

As for myself, while sampling for bugs in Glaisdale Beck I spied a strange brown shape floating downstream in a very odd fashion. It turned out to be a common toad that drifted ungainly towards me and bounced off my waders before bobbing off downstream – a little bewildered.

Common Toad - River Esk

As I was dipping a small pond beside the River Esk looking for smooth newts prior to hibernation I came across this enormous hawker dragonfly larvae at nearly two inches long, a top predator within the little pond.

Hawker dragon fly larvae

And we mustn’t forget the local ladies when discussing encounters for it is hard to visit many parts of the North York Moors without meeting farm animals of some kind or other.Cattle - Esk Valley

The creatures we come across may not necessarily seem exotic or exciting (except maybe for Simon’s mussel) on an international scale, but each animal and bird is part of the biodiversity of this corner of the world – and that’s important to us.

Revivifying a pond

Bill Shaw – Ecology and Conservation Land Management Adviser

Ponds are very important habitats for wildlife and used to be an important part of the farmed landscape, providing drinking water for livestock. Ponds are often close by houses, farms and villages – and so provide excellent opportunities to watch a habitat in action.

With the advent of mains water, which could be used to fill drinking troughs, the need for communal ponds declined dramatically and so they tended to be forgotten about or filled in to create more productive land.

A pond that is not cleaned out fairly regularly will naturally fill in with vegetation, become a marsh and then, over time, dry land. This process is called natural succession and, interestingly, if all land in the United Kingdom were left totally untouched nearly all of it would eventually become oak woodland – the climax vegetation.

Anyway, this loss of ponds has not gone un-noticed and there are a number of organisations working to restore ponds and dig new ones where possible e.g. the Freshwater Habitats Trust for one, and the North York Moors National Park for another.

Last year we were approached by some locals in Silpho village in the south east of the Park about their village pond which had dried out. The geology around here is limestone which does not hold water well, so to water livestock here in the past the pond had been dug and then lined with ‘puddled’ clay which held the water. These sort of ponds are called ‘dew ponds’ and, despite their name, they actually rely on rainwater to fill them up. During construction a layer of soot or lime was put under the clay to deter earthworms from burrowing through the clay and riddling the pond with holes!

Parish records showed that the pond had been constructed during the agricultural revolution in about 1800. In 1982 the clay liner had finally given up and the pond had dried out so a plastic liner was installed, but this had failed by 2012 and the pond had totally grown over.

The task for us (official and unofficial Volunteers, and National Park staff) was to remove all the vegetation and install a new plastic liner. This took two days and was very enjoyable, being a good mix of brawn and brain!



The pond will now fill naturally with rainwater and in the spring we’ll bring some suitable native plants in from a nearby pond – plants like water crowfoot, water forget-me-not, water soldier, hornwort, floating sweet grass, marsh marigold, water mint and yellow flag iris. I for one have put money on frogs breeding here this spring!

We’ve now got our eyes on three other ponds fairly close by that we want to reinstate, so creating a local network of watery homes for wildlife.

Chance encounters

Bill Shaw – Ecology and Conservation Land Management Adviser

On one of the many lovely warm days this summer I was looking for signs of water vole along the marshy banks of a stream on the moorland plateau, when I saw something move out of the corner of my eye. Looking round I saw it was a small, delicate frog hopping over the moss. Only about 1cm long it must have been one of this year’s youngsters.

Then I began to think about how often it is that most people’s encounters with wildlife are down to pure chance, and how exhilarating this can be.

I grew up in York and went on many walks with family and friends over the nearby North York Moors. Like many people who tramp the Moors regularly, I’ll never forget my first adder encounter as a child. I was running through the knee high heather when I suddenly stumbled across a large flat rock. On it, for a fleeting second, was a massive (to me!) brown zigzag patterned snake. Never having seen a real, live snake before I was amazed, and then rather sad when it slithered off into the heather and out of sight. Perhaps this was the beginning of my fascination with reptiles and amphibians.

I learnt later that this is typical adder behaviour – basking out in the open but darting off quickly at the first hint of danger. The individual I saw was a female; males typically are off-white with a black zigzag. The North York Moors provides a lot of excellent habitat for adders (Vipera berus) and we are lucky enough to still have good populations of this reptile.

Spring and autumn is when they are most often encountered, basking in the sun near their hibernation sites, which are often communal. Before breeding, males sometimes engage in a ritualised form of combat known as the ‘Dance of the Adders’ to decide who is going to mate with a female (see YouTube to see some fantastic footage). The young are born live in clutches of about ten during August and start hunting straight away. Their main prey is small mammals which they immobilise with a bite which injects a lethal dose of venom.

One of the great things about these chance encounters with wildlife is that it’s a win win situation – the more time you spend out and about in the countryside, the more chance you have of witnessing something special.