Category Archives: Mammals

The Lesser of Two Noctules

Everyone’s a sucker for a noctule. Big, brassy, sassy bats with an attitude. They’re about half a guinea pig in size (or, say, two large Syrian hamsters – ok bear with me, I’m trying here…) they are one of our larges UK Bats. I’ll admit that there’s something rather special about noctules – such a substantial bat is a novelty when the largest bat we see frequently in bat boxes is a Brown Long Eared bat and more often than not, our tiny Pipistrelles. However, size isn’t everything. There is something incredibly fascinating about Leisler’s Bats (aka Lesser Noctules). A calmer, generally more diminutive version of their larger namesake, there is something very inquisitive about their expression that I’m just in love with. (I blogged about the differences between the species a few months ago) I also hinted at surveys to come, so here we are – the beginning of a new bat box scheme aimed at recording Leisler’s bats at an almost entirely un-surveyed woodland.

20161203_121555

I rallied the BrumBats on Saturday to put up 25 bat boxes of different designs, many of which were rescued and repaired from other sites where they had been subject to vandalism. Six of the boxes were generously donated by local resident and wildlife enthusiast Sammy Benbow who came along to help us put them up. (Sammy is now one of the list of people that I’ve known on the internet for ages and have now actually met in real life! I love it when that happens!)

It is also going to give us an indication of whether bats simply take a long time to colonise boxes, or if it is because they are new boxes, as we’ve in several places hung them up in pairs: one old/refurbished box that has been outdoors for years & one brand new box. If the bats simply prefer the ‘new house smell’ to have dissipated before they move in, then they’re likely to go for the older boxes first. If they don’t much care either way, then we can expect them to go for both ages of box equally. (Of course, there is not enough of a sample size to reach any kind of quantifiable conclusion, but it is just a matter of curiosity on my part.)

So I’d like to say a huge thanks to Sammy, Jenny, Katie, David, Chris, Mike and Scott for helping on the day, braving the heights, the cold, the mud, the damp and the manual labour, all for the love of bats…

The Best Little Bathouse In Texas

I had a bucket list day on halloween. I was over in the US for a family wedding in Florida, and one of the big aims of the trip was for my brother Gaz and I to take my dad away for a few days. My incredible sister in law evidently went into full research mode, and arranged for a trip to Austin. We took the 2 hour flight  from Orlando (It was the first flight I’d taken with my dad since I was about 12 – we both hate flying, so spent the flight calming each other down!) and checked into our hotel.

What has the city of Austin got to do with halloween? Well, for bat workers, Austin, Texas is a bit of a bat Mecca, as it is home to a colony of 1.5 million Mexican Free-tailed bats which spend their days roosting under the Congress Avenue bridge, emerging and swarming each summer night.

20161031_133816
This is where I start to lose my shit.
20161031_133913
You can hear the bats as you approach the bridge.

Once we had checked into the hotel, we took a walk down to the bridge as a bit of a recce for bat-watching later that night. I wasn’t expecting to see anything, but it was a lovely walk along the Colorado River.  Within a few minutes I noticed a sign with a bat silhouette, and as I approached the bridge I could hear a high-pitched chattering noise coming from the underside of the bridge!

20161031_134502
Gaps in the underside of the bridge are home to 1.5m bats!

I was, needless to say, extremely excited – and I did a quick video in which (if you turn the volume up) you can hear the sound of the bats!

20161031_135313
The only MFTB guano I could find!

I did a bit of searching for guano, but the gaps above the path itself had, understandably, been filled up, I assume in an effort to stop walkers and cyclists on the path from getting guano in their hair! Eventually I found a single dropping on the river bank. I wonder if there is a significant nutrient increase in the water downstream of the bridge? Having seen how much a single bat deposits, 1.5 million is a lot of fertiliser!

The amazing city of Austin, TX
The amazing city of Austin, TX

After an amazing afternoon and a bit of trick-or-treating with my neice (AKA Doc McStuffins) we headed back to the bridge for sunset to watch the bat emergence.

20161031_185827
Probably the happiest I have ever been – waiting for 1.5 million bats with my amazing dad.

Because we were there in October, bat emergence took place after it was fully dark, whereas in the early summer you get to see the bats swarming against a light sky. But there was a good view under the bridge of some bats flitting about prior to emergence swarming:

I did my very best to get some photos and videos that show you just how incredible the sight was. It was without a doubt the most impressive natural phenomenon I’ve seen in my life.

20161031_194640
A blur of bats that continued for hours!

The Mexican Free-tailed Bat (AKA Brazilian Free-tailed Bat –Tadarida brasiliensis) is an insectivorous species, a bit bigger than some of our Myotis bats here in the UK – MFTs weigh in at around 12 grams (1 MFT = two fat pipistrelles). Below are some pics of the one that I got to meet a few years ago at the Florida Bat Conservancy. You can see where the ‘free-tailed’ part comes from, as unlike our UK species, the tail membrane (patagium) doesn’t join onto the bat’s tail at its tip, but instead the tail itself extends past the edge of the membrane. The are famous for the enormous size of their roosts.

Mexican Free-Tailed Bat (Tadarida brasiliensis)

The cool thing is that these bats don’t hibernate like all of our UK species – they migrate to Mexico instead! By the middle of November the bats are gone from the bridge, not to return until spring. Alas, I cannot migrate to Mexico, but must instead endure the British winter, hopefully with some wintery wildlife adventures coming your way shortly…

20161031_135054
JT the travelling bear really loves Austin!

JT Bear had a great time, too! JT Travels the world raising money for the Sarcoidosis and Interstitial Lung Association and the British Lung Foundation. Last year he walked across Scotland! Please follow the links to each of these charities if you’d like to donate!

3f108c_9cf6d8bfd0494e798b07ab287ee9395e-mv2logo

Badgers Back to Back

I’m so excited, because it’s trailcam season again! After a mental newt season followed  by a hectic bat season, the early sunsets mean that not only can I sleep more than 4 hours a night, but my attention can turn to one of our most enigmatic animals – badgers. I’ve only had the trailcams out for a week so far, but already have captured some awesome footage, and have plans to find out just where they’re going and what they’re doing in the long autumn and winter nights. However, as for this week’s footage, in spite of some technical hitches (One camera failed completely and the other wouldn’t format – but I’m hoping that tech support can fix it.) we had some great footage and made some interesting notes…

The video above shows some cool behaviour – basically tussling about, a bit of biting here and there. (You can see this on and off all the way through, but it doesn’t seem to be outright aggression as they soon revert to mutual grooming.) Fighting is more often between females, and can be done for social dominance reasons, territorial disputes or associated with mating. Also keep an eye out in the video above for what the books call ‘bum-pressing’ – basically anointing each other with their scent glands – they lift their tail and rub their bums on each other in order to ensure that all of the members of the sett share their particular cocktail of scents! (Don’t try this at home!)

Another great bit of behaviour we caught was the changing of bedding. Usually done by less dominant females and dominant males, the badgers pull out old bedding from the sett (which you can see in the video below – watch for bums wiggling backwards out of the sett entrance!) and then collection of bedding to bring back to the sett. The badgers do this by dragging a bundle of bedding in their front legs as they walk backwards to the sett entrance. It’s a really cool thing to have caught on camera.

The interesting thing is that none of the aggressive behaviour took place on nights where bedding was being changed. They seem to be in full ‘cooperation mode’ when work needs doing. You can also see grooming and scratching behaviour in the video below. They do a lot of self-grooming, but also do it for each other too.

We have recorded four badgers at any one time on camera, but we know that there is a 5th badger, not seen interacting with the others, but that also uses the sett. He’s easy to spot because he only has one eye:

oe1 oe2

Watch this space for more badgery goodness!

I Like Big Bats (& I cannot lie)

So I’ve had a bit of a hiatus from blogging and social media, due to personal reasons, but I have lots to share with you and catch up on – not least, the significant finds as part of the BrumBats Batlas project and our bat box scheme. I’m going to blog this weekend about our second (and most exciting) discovery, but for now I want to talk about big bats.

There are three closely-related species of bat which are generally lumped together as being our ‘big bats’ in the UK: serotine (which I’ll focus on another time), noctule and Leisler’s bat. The latter two species are pictured below, and are superficially similar. They are both quite chunky bats, with the tragus (the flap of skin inside the ear) shaped like a mushroom, but the noctule is larger (weighing in at up to 40g – twice the weight of a Leisler’s) with paler (often gingery) fur compared to the dark brown fur of Leisler’s bats. Leisler’s also have a thick ‘mane’ of ruffled fur around their shoulders and head.

Noctule
Noctule
Leisler's
Leisler’s

Noctules (Download the BCT factsheet here) are one of our largest UK bats, and are fairly ubiquitous, found throughout Birmingham and the Black Country, whereas Leisler’s bats (aka ‘lesser noctule’ – fact sheet here) were until recently only know at a couple of sites. The 2002 mammal atlas (Which you can download here) shows their distribution as follows:

As you can see, Leisler’s bats are fairly scarce. Or are they?

You see, in the 13 years since the atlas was produced, BrumBats have been actively recording bats across the county, and (especially since the 2014 launch of our Batlas Project) we have recorded noctule in pretty much every tetrad we’ve surveyed.

(BTW, the maps don’t look like this anymore. The thing is with distribution maps is that they are a map of the RECORDS of a species, not of the species itself, and often are a reflection of recorder effort. If a person is really into recording bats, they are likely to have concentrated their efforts in ‘likely’ or ‘favourite’ spots. This is where systematic surveys like the Batlas come in – they dilute the skew on the data provided by biased recorder effort.)

So noctules are apparently all over the county, but Leisler’s bats are a different matter. In 2015 we had a Leisler’s bat come into care from Wightwick Manor National Trust. The bat (which subsequently died of his injuries) was found at the bottom of their chimney. The Batlas Tetrad survey of that area the following year recorded Leisler’s bats foraging over a nearby woodland. So they are definitely in at least the outskirts of Wolverhampton.

Then, last year the awesome folks from the Herefordshire Mammal Group led several nights of mist netting and harp trapping for us. On one of these nights we caught a Leisler’s in a harp trap at a previously un-studied LNR in Walsall – not far from the town centre!

Then earlier this year, our successful bat box scheme at Merrions Wood turned up both Noctule AND Leisler’s using the boxes for the first time! So now we know some actual roosting sites, rather than just errant records of noctules flying over our area off to who knows where looking for food. This is all good stuff!

So I’m pretty excited about this, as we are getting an idea that although perhaps not abundant, Leisler’s are probably at least widely distributed across the county, just like noctules. But this then begs the question – how many of our noctule records are actually Leisler’s bats?

It is easy to fall into the trap of assuming that because we are in an urban area, we’re only going to have crap (sorry, common) species. I see this type of assumption made all the time over a variety of taxonomic groups. In the case of noctule and Leisler’s, both species echolocate at a peak of around 25kHz, with relatively similar calls (listen to Noctule and Leisler’s here) – pretty similar, right? You can separate them on sonograms, but not reliably just by ear.

lelislers
Sonogram of Wightwick Manor Leisler’s bat calls

I believe that Leisler’s bats are probably drastically under-recorded in our county. They are an adaptable species that we know can thrive in urban habitats (they are ubiquitous in urban parts of Northern Ireland, where noctules are not present at all).

So I’m hoping to focus future survey efforts on rarer (or under-recorded) species in the 2017 season, and I simply cannot wait! Stay tuned for even bigger news next week…

First Bats of the Year

April is the start of the bat survey calendar. After a winter of hibernation, bats are waking up and beginning to feed up for the season. Bats mate in the autumn and use seasonal delayed implantation (also called embryonic obligate diapause, a technique for ensuring that young are born during times of plentiful food) during the winter, allowing themselves to become pregnant once food is abundant.

(I once had a female bat come into care due to injury in the winter. Some weeks later she gave birth to a pup, and knowing bat gestation periods, I worked out that she allowed fertilization to take place within 48 hours of being exposed to warm temperatures and ample food!)

Saturday was the first of the BrumBats bat box checks for 2016, and though it was in a short but sharp drop in temperature (It snowed at 7am!), we still found bats. Four noctules were found in one of the Schwegler 1FF bat boxes – the same box we found a single noctule hibernating in when we did our box maintenance in January.

As bats are a European Protected Species, it is illegal to disturb them – this means even torches, so at least a Class 1  survey licence from Natural England is required if you just want to use a torch to shine up to check if they are occupied, and a Class 2 survey licence to check bat boxes and handle bats.

The bats are gently removed from the box and placed into cotton bags to reduce stress. We keep handling to a minimum, taking some basic biometrics: forearm length using vernier calipers or wing rules, and weight using spring scales – these measurements give us an idea of the health of the bats. Our four noctules all appeared to be in great health!

Vernier calipers being used to measure forearm length on a Noctule bat.
Vernier calipers being used to measure forearm length on a Noctule bat.

This first survey is a great start to the bat box season. We have two new bat box schemes so will hopefully have info on their success soon! All the bat records feed into the Batlas Project, helping us to get a clearer picture of the distribution of bats in our county.

Box Fresh

It’s always a good day when you get to start a new project. Today I went out onto Brownhills Common with Ben and Scott to install 20 of our new bat boxes. The scheme is funded by Natural England through their Countryside Stewardship scheme, and through it we’ll be installing another 30 boxes on the SSSI site. I expect that the scheme will be quite successful, primarily because of the nature of the site. Brownhills Common is an area of heathland which, although comprises a variety of different habitats, lacks the mature, broad-leaved woodland that characterises the other sites in our bat box scheme. Instead, the trees are mainly Scots Pine (Pinus sylvestris) and as such there is not much in the way of natural roosting opportunities for bats. (Conifers do not tend to have the tendency to form fissures, natural cavities and loose bark that, say, an oak tree does.) In the wild, it is such cavities that bats look for to roost in, and without lots of natural choice, an artificial substitute can be very inviting to a bat!

The boxes we put up at this site are Schwegler 2F boxes, which we’ve had some success with in my other box schemes (most recently we recorded Noctules using the 2F boxes in Merrions Wood). I also have 20 Kent style boxes to go up (These are wooden boxes and not openable, so would not be checked except with a high powered torch from the ground, and then with an endoscope if anything interesting appears to be inside.) and 10 Schwegler 2FN boxes (slightly larger than the 2Fs and with a domed roof) which have been used to some success in areas of nearby Cannock Chase.

Those of you who are local might also have noticed the 28 bat boxes at Walsall Arboretum, near Hatherton Lake. This afternoon we headed over there to number and geolocate the boxes, as well as give them a winter clean-out and reposition a few of them (raising them higher). As this was their first year in position, they had not been checked during the summer, but to our surprise around 1/3 of the boxes had bat droppings inside today. (We suspect pipistrelle and are pretty certain of Brown Long Eared bat droppings in quite a few boxes!) So all in all I am really excited about the bat box scheme’s expansion for 2016.

OLYMPUS DIGITAL CAMERA

One sad little note, is that in one of the Arboretum boxes we found this nest with a couple of unhatched eggs and three dead hatchlings. We have no way of knowing what happened to the mother bird. Quite often we find bat boxes that have both old bird nests in AND bat droppings – they don’t seem to be mutually exclusive. This is probably due to a few factors: the bats and birds use different PARTS of the box (birds in the bottom, bats at the top); the bats and birds are active and using the entrance at different times (birds being diurnal and bats nocturnal) and the fact that the main maternity season for bats in the UK is July, and by this time, many baby birds will have fledged.

The other boxes will go up as soon as possible (within a week or two I should think) and we can then look forward to the first of the 2016 box checks in April!

Here be Badgers

For the first time in 2016, last night I set out my trail cameras near the Hogsmeade badger sett. It appeared that over the last few weeks there had been some activity digging out sett entrances and whatnot. My mate Scott and I had recently discovered a scratching post near the sett and were keen to see if we could capture some of this activity on film.

Scratching posts are often found near sett entrances and there is some debate about the reason that badgers seem to relish scratching at old (usually Elder) trees – perhaps to stretch, to clean their claws, or event to sharpen them. You can find them by looking for deep, vertical scratches on trees near the sett, with the scratches reaching perhaps a metre (3 feet or so) up the tree, and running sometimes down to the ground.

Many years ago, when I first went on a badger survey course, I was told that these trees are called ‘Totem Trees’ and I have always called them that since. However, I can’t seem to find any reference to that on the internet, so perhaps it was a term colloquial to the badger group in Suffolk at the time that I was learning.

Other signs of badger activity include their trademark footprints – a kidney-bean shaped pad of the foot, with 5 little toes lined up above the ‘bean’. This will be with (front foot) or without (hind foot) long claws (there is a gap between the toe pad and the claw because they are so long!). The whole combination gives the impression that tiny little bears have been running around! The photos of prints in this post were taken when my friend Helen and I went to collect in the camera traps this morning, so clearly there was some activity last night. Near sett entrances and on fences or brambles, you may also find badger hairs, which have three different colour tones, and are non-circular in cross section – more triangular. Now, you won’t see this with the naked eye, but you can see the effect that it creates – roll the hair between your thumb and forefinger and you’ll feel it jump about rather than rolling smoothly. I did a slow motion video to show you:

 

A video posted by Morgan Bowers (@thereremouse) on Jan 28, 2016 at 2:26am PST

(Having a bit of trouble with the embed code, so here’s the direct link to the video: https://www.instagram.com/p/BBFE6DHpV4h)

Incidentally, we had no badger activity on camera, in spite of it being a dry night. There could be a reason for this – as it is at this time of year (January & February) that badger cubs are born. It warms my cockles to think that under my feet the sow might be snuggled up preparing to give birth, or even nursing two or three new cubs. With ongoing monitoring, I hope to film the cubs in the early spring when they first start to venture from the sett, and will of course post on here when I do!

Anyway, the trail cams are out again tonight, so may have more to show you tomorrow!

Winter Mammal Update

With the help of the Black Country & Staffordshire Naturalists group, I’ve been continuing to monitor the mammals on our local nature reserves, including bats and badgers. As you’ll know if you’re a regular on here, we give each of our badger setts fictitious names in order to protect them and keep their location a secret. We’ve been giving special attention this winter to the Hogsmeade badgers, as they appear to have been particularly active, but we don’t seem to be able to be in the right place at the right time to catch them on camera. After a few problems with my trailcams (not entirely sure what is going on, as the problem persists intermittently) we finally managed to get an evening’s worth of footage, including the return of a one-eyed fox (whom we have called Mad-Eye Moody), an extremely hyperactive mouse and a couple of fat badgers…

In addition to trailcam setting, we’ve been out and about with the endoscope, looking for hibernating bats. Last week we found this hibernating Brown Long Eared bat in a tearaway cavity in a tree in Merrions Wood.

We returned to Merrions Wood today to clean out the nests left behind by feathered squatters this summer, and to our surprise found five noctules – one in one box and four in another. They have been left in peace, but we did shoot a bit of sneaky endoscope footage of the first one, which you can see below.

It really is great news that noctules are using our bat boxes, as until now we only had confirmed use by Brown Long Eared and Soprano Pipistrelles. Here’s the endoscope footage:

The next plan is to move onto our Sunnydale badger sett to see how our badgers there are faring, which will happen later this month.

 

Tasting the Wild in 2015

My year in review. (In photos!) I’ve had another amazing year – looking back, I’m not entirely sure how I’ve fit it all in!

Wild Encounters

From Chasing Violet Carpenter Bees in Andalucia, hunting for Eyed Ladybirds on Barr Beacon and moth trapping on heathlands around Walsall to mist netting for bats in woodlands, ringing birds (including our Peregrines which fledged four chicks!) and monitoring our amazing badgers, I’ve had another amazing year of wild encounters.

Wild in the Woods

I’ve also done lots of playing in the woods this year, and have concentrated on working on my fire craft skills (from just practicing lighting fires to experimenting with different tinders and kindlings). I’ve made a willow crayfish trap and learned some new basketry techniques, honed my corn dolly skills and bashed the heck out of some plants to make hapa zome flags. Culinary foraging has been limited to hedgerow berries and birch sap tapping this year, but I’m still reaping the benefits of my hedgerow vodka!

Travel

Kind of spent a ridiculous amount of my pocket money on travel this year, with a trip to Andalusia in March, followed by Edinburgh in May, the 5th annual Girls’ Birdwatching Trip (Norfolk), camping in the Derbyshire Dales and hiking from Ft William to Inverness. And I wonder why I have no money now that December is here! Highlights were definitely the seals at Blakeney Point and my first ever glimpse of the Aurora Borealis whilst camped on Loch Ness – amazing! (You can read the blog and see the videos of the hike across scotland here.) I’m planning on Florida, Cornwall and lots more camping in 2016!

Bats

Oh, the bats this year! I’ve been involved for a few years with the Herefordshire Mammal Group, doing mist netting and harp trapping surveys, and this year their project organisers helped BrumBats to undertake some woodland surveys of our own. With help from the Shropshire Bat Group, we surveyed Cuckoos Nook & the Dingle, Merrions Wood and Sutton Park. At BrumBats HQ we are very excited to get stuck into another season of study!  We also had a crazily busy year of bat care, and with this mild weather, are anticipating some winter grounded bats and (most likely) a very busy (and early) bat maternity season in 2016!

Space

The sun and the moon had amazing things in store this year – a total lunar eclipse, and a near-total solar eclipse. Both events had (uncharacteristically) clear skies. Over 600 people turned out on Barr Beacon for the solar eclipse. Amazing that so many people value natural phenomenon enough to come out and experience them together. The atmosphere was just incredible! I’m hoping to be in the USA for the total solar eclipse in August 2017.

Botanising

I had a fantastic summer, spending most of it undertaking botanical surveys of grasslands. I think we’re going to get a few new nature reserves out of it, and certainly some relaxed mowing regimes.

Becoming an Auntie again…

In January I became an auntie again – this time to a little girl – the enchanting Eleanor Hughes, whom I’ve got to spend time with twice this year (which is pretty good going seeing as she lives 3,500 miles away!). Can’t wait to see you in March, Elley!

OLYMPUS DIGITAL CAMERA

I hope that everyone has had a merry Christmas full of comfort and Joy, and I’m sending you wish-grenades for a prosperous, healthy and bright new year!

Thanks, as always, for reading. If there’s anything you’d like to see me cover in 2016, please let me know!

Morgan x