Tag Archives: Ecology

Ep 8: Year in Review

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Content:

00:00 Intro to updates – reviews of 2016
04:35 Top successful wildlife quests of the year
09:04 Unexpected wildlife win of the year
12:16 Mammal of the year
14:12 Bird of the year
18:20 Plant of the year
20:00 Wild Place of the year
24:50 Topic: 99 reasons why 2016 was a good year
40:30 Looking forward to 2017

Links & Pics We Promised:

Ep 6: Pizza, Values and Winter

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Content:

00:42 Charlene’s F-Quest results!
05:24 Leigh talks about the trip to Falmouth
11:10 Morgan talks about Congress Avenue bats in Austin
16:32 Leigh’s bird ringing expedition
25:09 Why do we not choose to protect the planet more?
42:23 What do ecologists do in winter?
47:27 What are we reading: Daughter of Eden by Chris Beckett

Wild Places:

Links & Pics We Promised:

What are you Reading (Reviews):

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…

Ep 3: Specialise or Generalise

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Content:

00:15 Updates on our Bird Listing & Wildlife Sightings
16:48 Moth Trapping
31:35 Specialising or Generalising in ecology
45:25 What Are You Reading (Recommendations)

Wild Places:

Recording Schemes:

Kit & Other Stuff:

 and

The green one is more complete with greater detail on distribution, ecology, etc, but the orange is a concise version. We recommend getting the orange spiral bound one! But they are the same book with the same number of species in them.

Links & Pics We Promised:

Chinese Water Deer!! OMG! #mammals

A post shared by Morgan Hughes (@thereremouse) on

  • TED talk about being a polymath:

What are you Reading (Reviews):

  • Apple app – Collins Bird Guide (double check if on Android?).

FYI:

Wiki on Egyptian Geese:

This is a largely terrestrial species, which will also perch readily on trees and buildings. ….

This species will nest in a large variety of situations, especially in holes in mature trees in parkland.

The female builds the nest from reeds, leaves and grass, and both parents take turns incubating

eggs. [8] Egyptian geese usually pair for life. Both the male and female care for the offspring until they

are old enough to care for themselves. [13]

Email darwinsdolls@thereremouse.com

Knowing your Newts

Newt survey season runs from mid-March to mid-June, with the peak season being mid-April to mid-May. I’m doing quite a bit of ‘newting’ this year, and it occurred to me that I’ve never done a blog post about separating great crested newts and smooth newts.

The first major difference is size. GCNs, when fully grown, are whoppers compared to smooth newts. Take a look at the photos below of a smooth newt male vs a GCN female, both in the bottom of 2-litre bottle traps…

Great Crested Newts are black in colour, with tiny white bumps (which give them their other common but erroneous name – ‘Warty Newt’). They feel slightly rough to the touch. (So I’m not joking when I say “I can identify a Great Crested Newt with my eyes closed!”)

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Female GCN showing white bumps and orange toes

They also have bright orange bellies (with no white or cream), with elongated black splotches in. The orange colour extends along the underside of the tail, and the tips of their toes are bright orange:

Males (and only the males) also have a silver flash on the tail, and (when in breeding condition) a large, elaborate, jagged crest down their back, which gives them a bit of a Godzilla vibe. The GCN really has TWO crests – one for the back and one for the tail, as there is a noticeable break in the crest where the tail joins the body.

But don’t let the name fool you, because Smooth Newts also have crests! Read on…

Smooth newts are, well, smooth. They are extremely variable in colour, and like the GCN are sexually dimorphic (males and females look different). Males can be brown or almost black, with big round black spots on an orange and cream-coloured belly, whereas females are usually a variable shade of brown or orange. Females also have a pale orange and cream belly, but the spots are fine speckles rather than big splotches. Female toes don’t look ‘painted’ like a GCN, and male hind toes are flattened and fringed. In a smooth newt, the crest is continuous and runs the entire length of the body, and is wavy rather than jagged, matching the wavy outline of their feet. Think of it as matching tie and shoes.

Below are a few comparison photos. Firstly, a photo of an adult female smooth newt with an adult female GCN (to illustrate the incredible size difference):

GCN (L) Smooth (R)
GCN (L) Smooth (R)

Here’s a comparison of the bellies of male GCN (L) and Smooth (R) newts:

And male smooth (L) vs GCN (R) toes!

To make things significantly confusing, for half of the year, this sexual dimorphism isn’t there – and fringed toes and silver tail flashes disappear for the winter, and the crest reduces to almost nothing – often seen as a faint line down the backs of males. Generally speaking, GCN males and females are harder to tell apart at that time of year, or before they reach sexual maturity. It’s a bit easier with the smooth newts as the belly patterning remains fairly distinct. But even the larvae of these two species can be separated.

By August there are larvae swimming about in GCN breeding ponds. Because GCN and smooth newts will readily cohabit in a pond, the larvae of both species are present. The difference is pretty astounding. Here’s a photo of the two species at roughly the same stage of development:

And another:

Smooth vs GCN larvae
Smooth vs GCN larvae

So as you can see, the GCN larvae are massive, compared to a similar age of smooth newt. The GCN also have distinct splotches on their body.

So now you know how to tell them apart. The sharp-eyed among you will notice that I have left out Palmate newt, largely because I don’t encounter them often here in the midlands, and as such don’t have any photos, but also because telling palmates from smooth newts is a little trickier, and I’m likely to have a proper rant about poor biological recording practices. 😉  A tale for another day, perhaps?

*Please remember that it is illegal to disturb, handle or even photograph a Great Crested Newt, as they are a European Protected Species and you need a licence from Natural England to disturb them. If you’d like to get involved in amphibian surveys and conservation, contact your local ARG (Amphibian and Reptile Group), or contact Froglife and ARCTrust.

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.