hibernation – Grantham Ecology

2017 Retrospective – The Rest!

December 31, 2017Grantham Ecology1 Comment

I like to take the opportunity which the end of the year presents to look back over what I’ve seen and encountered. Some fall nicely into groups so do check out trees, wildflowers, butterflies, bees and invertebrates on their own posts!

The remainder are individual species or places which don’t form a group, but which are an important part of the year just passed. I hope you enjoy!

Easegill Bat Surveys

I was lucky to be invited along to a hibernation check in the caves in Easegill, Cumbria by a friend in the bat group there. We found a number of hibernating myotis and brown long-eared bats in the various cave systems, along with the tissue moths, herald moths and cave spiders which use the same habitats over winter. It was a great day out in some stunning scenery, and the opportunity to do a spot of caving whilst searching for wildlife was a real treat! You can read more, and watch a short compilation video, on this post from January 2017.

Snowy walk along Stanage Edge

It takes around an hour and a half for us to get to some of the most stunning walks in the Peak District; a bit of a trek but always worth the visit especially if there’s snow to line the fields and de-mark the landscape with its series of hedges and stone walls. I love too how the hills in the far distance can give an illusion of mountains when they become snow-covered!

Smooth newt – Lissotriton vulgaris

I couldn’t resist this photograph when we were undertaking translocations at the beginning of the year. The legislative driver behind the translocation is the great crested newt, but we take the opportunity to move any species we encounter to a place of safety. With the juveniles, such as this little smooth newt, you need to keep a sharp eye to make sure you spot them all!

Common frog – Rana temporaria

Spring is one of the most rewarding times to have a garden pond – when the croaking begins and the surface is a mass of calling frogs. This was taken on a cool March day when the frogs had decided that spring had sprung! In this photo, I tried to capture the turbulence of the water which these amorous amphibians bring to a placid garden pond.

Slow worm – Anguis fragilis

We encountered this slow worm under a piece of corrugated metal in the woods near Woodhall Spa in the early summertime. There had been a rainshower which caught us out and the slow worms too had taken shelter. As the sun came out and the corrugated metal began to warm, the chances of catching one reduced significantly as they are anything but slow when they want to be! These reptiles are in fact legless lizards rather than snakes. Their habit of sheltering beneath these artificial refugia forms the basis of the reptile survey technique we use in ecological consultancy to find out whether reptiles are present on a particular site.

Dandelion seedhead before the full moon

The was taken at Muston Meadows at midnight when the moon was full and I couldn’t resist a walk. The dandelion seedheads glowed white against the dark grass but I was struggling to capture this in a photograph – then I thought this might make an interesting angle!

Shropshire Hills

We spent a few days over the May bank holiday in Ireland for a wedding, coming back via Anglesey and spending a night in Shropshire on our way back east. We walked over the Long Mynd at dusk, heading back towards our campsite, and this was the view as we began to descend.

Church of Saint Mary, Whitby

A weekend camping near Robin Hood’s Bay in the summer found us in Whitby before walking back along the coast. This is the taken at the Church of Saint Mary – set above the town and referenced in Dracula. I was struck with this view of the tombstones dark against the long meadow grasses and wished this was a more common sight – cemeteries and churchyards can be beautiful places full of life after death, if they’re managed sensitively for wildlife rather than manicured as bowling greens!

Curbar Edge, Derbyshire

We had a survey site which saw me out in the Peak District until 7pm one evening in August – after which I took the opportunity to see the heather and take a walk along Curbar Edge at sunset. This is the view out across from the Edge as the sun was sinking low on the horizon.

Vancouver Island

The following are a few photographs from Vancouver Island this year – we encountered some spectacular wildlife and were amazed by the scenery. You can read more in my blog posts here, but below are a few highlights.

Anna’s Hummingbird in Victoria

American red squirrel at Long Beach, Tofino

Black squirrel in Stanley Park, Vancouver

Orca’s from Victoria

Grey heron reflection against the vending machines on the marina in Vancouver

Slow worm – Anguis fragilis

This tiny slow worm was one of this year’s juveniles – we were surveying a site in Somerset and this was one of seven young ones which appeared under a single survey mat where the sun warmed a bank at the edge of the site. When I picked it up, it wrapped itself around my finger but was so small that the nose and tail didn’t quite meet!

Sunrise on the day of Storm Ophelia

This photograph was taken of the countryside in Warwickshire on the day Storm Ophelia swept across the UK. At that time, I didn’t realise what was causing the effect but was just taken by the colours – it turned out that the day was to be filled with the pseudo-apocolyptic light brought on by the Sahara sands.

Cattle at Muston Meadows

Muston Meadows is an ancient haymeadow and a National Nature Reserve in Leicestershire. The site is managed with a late-summer hay cut and is grazed in the winter by cattle. I visited one frosty morning in December and they were delighted to have a visitor, charging over before stopping and checking me out. They then accompanied me all the way off the site so perhaps their role is security as well as site management!

Icicles under Burbage Bridge

On a snowy cold day in December, I took a walk through the white from the Longshaw Estate in Derbyshire, through woodland and across tors and encountering these beautiful icicles hanging beneath the bridge which takes the road over Burbage Brook.

Clematis seedhead – Clematis vitalba

These are also commonly known as old man’s beard and it’s easy to see why! I came across these seedheads in a hedgerow on a survey site in Bedfordshire where the wind had left them with this shape over time – I liked the feeling of motion which they held even when still. It seemed appropriate for seeds which are waiting for their time to take to the wind and begin a new plant elsewhere in the landscape.

Teasel seedheads – Dipsacus fullonum

On the same site as the clematis above, I also found an amazing stand of teasel seedheads. These striking plants are excellent for wildlife – in the summer they provide an abundance of nectar for pollinators such as bees and butterflies, and the winter seedheads will play host to flocks of goldfinches foraging for the seeds.

Easegill Caves Hibernation Surveys

January 24, 2017Grantham Ecology1 Comment

The Cumbria Bat Group kindly let me come along on a hibernation survey at Easegill Caves in January 2017. We hiked up to Upper and Lower Kirk Caves to see what we could find, then descended using ropes and caving ladders into Link Pot to explore an underground cave network some 15m down.

We found good numbers of myotis species including Daubenton’s, Natterer’s and whiskered/Brandt’s/Alcathoe – these last three are grouped as it’s very difficult to distinguish these three without disturbing the bats. We also found a small number of brown long-eared bats hibernating too.

It’s important to note that disturbing hibernating bats is illegal without a licence from Natural England – this survey was led and supervised by licenced bat workers who ensured that disturbance was kept to a minimum whilst allowing the bats to be identified and counted. If you find a bat in roosting you should take great care not to disturb it especially during the winter as they may rouse from torpor at an inappropriate time and be unable to then survive the winter. If you do find a roosting bat – let your local Bat Group know! More details at the bottom…

The video below shows a summary of the seven hours we spent out in the hills, in just under three minutes!

The following photographs show a few of the hibernating bats we identified on the surveys.

It’s not only bats we found in the caves – plenty of cave spiders and hibernating moths too including herald and tissue moths.

If you would like to get more involved with your local bat group and help out on hibernation surveys such as these, you can find your nearest here. Many thanks to the South Cumbria Bat Group, and Rich Flight in particular, for a great opportunity to explore the caves and see plenty of roosting bats!

Hibernating drone flies

October 2, 2014October 3, 2014Grantham EcologyLeave a comment

It’s autumn and those creatures which hibernate through the winter are beginning to make their preparations. The squirrels are out burying nuts to tide them through, the bats are fattening up on insects to see them through torpor and those invertebrates which sleep the winter away are looking for safe places to stay.

A likely indicator of a hibernating insect is an early appearance in the spring. This is true of the brimstone butterflies which, for many, heralds the start of spring, and also the rather ungainly named drone fly. This is actually a hoverfly – Eristalis tenax – which is named not for the sound it makes in flight but for its similarity to a honey worker bee, a drone. These flies can often be seen early in the springtime, taking advantage of the first available nectar sources such as the lesser celandine pictured below.

Drone fly - Eristalis tenax - on a lesser celendine — Drone fly – *Eristalis tenax* – on a lesser celendine

We visited Tattershall Castle last weekend – a National Trust property out near Lincoln – and spotted several of these drone flies investigating crevices and cavities in the roof of the kitchen at the ground floor of the castle. You descend here down a small flight of steps and this movement below the ground will appeal to the hoverflies – conditions tend to be more stable and remain above freezing when you are beneath the ground level. Stability of conditions is often as important as suitable temperatures – a stable environment means less false signals that spring is here and emerging from hibernation too soon is never a good idea!

Drone fly investigating a hibernation site at Tattershall Castle

The hoverflies were not alone – tattered small tortoiseshells and red admiral butterflies were also checking up and down the walls for a safe place to roost for the winter whilst herald moths were already settled and looking set to sleep until spring.

Tree bumblebees in Grantham

February 27, 2014Grantham EcologyLeave a comment

Bumblebees are fascinating insects and I have been meaning to learn more about them for a long time. I’m not sure that it doesn’t have something to do with the fact that they looks quite so similar to colourful bats up close… there is something about their furry round bodies which is rather reminiscent!

It is still very early in the season but most of our UK species respond to conditions rather than dates and when the sun is shining and the weather is mild, many hibernating species will come out of torpor and begin their spring routines. I have recorded pipistrelle bats in flight over the last week; the birds are certainly thinking about nesting with the early species such as long-tailed tits gathering nesting materials; and there was quite a gathering of bees on a very early flowering blackthorn on Monday lunchtime.

I managed to get a couple of photographs of this bumblebee and decided that this would be the first ID on my path to learning more about these species. And it looks as though I picked quite a good one – my tentative ID of a tree bumblebee (Bombus hypnorum) was confirmed by helpful tweeters @sbd08simon and @ed_p_wildlife. Apparently there is no other bee which this species can easily be confused with – the colouration is just black and buff-brown with a white tail. No coloured bands! This bee has quite a simple pattern compared with the multitude of variations which other species seem to manage! This guide from Bumblebee Conservation gives a great introduction to identifying bumblebees.

Although I am, as already confessed, no expert, I believe this must be a queen out foraging and potentially searching for a nesting site. The queens emerge in spring (usually March or April) and scope out potential nesting sites before laying their eggs. About six weeks later, the eggs hatch and the entirely female workforce splits into teams, some foraging for the colony, others staying in the nest to do the housework. Later in the year, ‘reproductives’ are produced – these are virgin queens and/or drones. The drones will die after mating with a female but the queens will hibernate through the winter and emerge when the temperatures warm up in the spring and the cycle can begin again. I would therefore suppose that my bumblebee feeding in February is a queen freshly emerged from a relatively short winter’s sleep.

Tree bumblebees are so called because of their habit of nesting in trees – either in woodpecker holes or more frequently, in nest boxes. Like most species, they have adapted to inhabit the world we have created around them and can also be found nesting in houses, in soffit boxes and similar features. Some other species of bumblebee will occupy similar niches but the preference for these tree (or tree-like) nesting sites is most notable in the tree bumblebee. Many other UK species will nest underground and you can often see them bumbling into the undergrowth towards the entrances to their underground homes.

Tree bumblebees are a relatively new additional to the UK’s fauna – they first appeared in Wiltshire in 2001 and have been spreading north every since. It is believed that they are natural colonisers which have established under their own steam, much like the collared dove which was a rare vagrant until the 1950’s when they were first recorded breeding here and now grace most garden bird tables across the UK. The invasion of the tree bumblebee appears, so far, to be benign with no observed impacts upon existing native bee populations and its spread appears to be continuing with the first recording in Scotland last year.

I have recorded my sighting here – the data gathered from recordings around the country can be used to study this species and describe its distribution around the country.

If you want to read more about the tree bumblebee, there is a very informative factsheet available from Bumblebee Conservation.