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Earthworm News Volume 5, Issue 2 Winter 2014
In This Issue
News
page 2
Earthworm Survival Tactics
in Flooding
and
Recent Publications
Recording
page 5
ESB Field Meeting 2014
Events
page 8
Events Coming up in 2015
Species of the season
page 10
The morphs of
Allolobophora chlorotica
Curiosity Page
page 11
The Truth About Velvet
Worms
Slime Time
page 12
Puzzle of the Season
Dear members,
We have had a busy year at the Earthworm Society. Last
year’s wet winter prompted lots of questions about how
earthworms survive in flood conditions - we have now got
an answer to your questions in ‘Earthworm Survival
Tactics in Flooding’, on page 2.
We have also held our first three field meeting weekends.
All were a great success! There is more information about
the field meetings on page 5. Our Kent field meeting
report will be published shortly. You can find our other
field meeting reports on the ESB website.
We have updated our website so there is more information
about sampling and recording; including the forms you
will need if you want to collect your own records. We are
adding more pages soon, so keep your eyes peeled at
www.earthwormsoc.org.uk.
Remember we still have our Facebook page which we
update regularly - https://www.facebook.com/
earthwormsoc
We are currently planning events for 2015 and will be
sending out information shortly!
We hope you all have a wonderful Christmas and New
Year.
Best Wishes
Rachel
ESB Newsletter Editor
2
News
Earthworm News Volume 5, Issue 2 Winter 2014
Hot Earthworm Topic
Last winter saw record breaking
rainfall, particularly around the
Somerset Levels in South West
England. The flood waters covered
over 17,000 acres and this land was
underwater for over a month. The
floods caused devastation to homes,
agriculture, businesses and wildlife.
During this period we got many
enquiries about the impact flooding
had on earthworms.
Little research has been done on the
impact of flooding on earthworms in
the UK. Eiseniella tetraedra, thrives in semi-aquatic environments such as floodplains,
whilst other species have adapted to survive an increase in water levels through physical or
behavioural methods. Many species migrate (behavioural adaptation) to drier, less
waterlogged environments if they have the chance. Other species such as Allolobophora
chlorotica, Aporrectodea caliginosa and Lumbricus rubellus have adapted physically to
survive within waterlogged conditions.
Freshwater v Seawater
Coastal flooding, which is caused by saline
water (sea water), has a negative effect on
earthworm populations. Earthworms tend
not to thrive in coastal areas influenced
heavily by the sea. This is due to the high
salt levels, which lower the microbial
populations (such as bacteria, fungi and
viruses). In turn this reduces the oxygen
levels in the soil which are essential for the
survival of earthworms.
Flooding with freshwater found in rivers and
streams provides a better environment for
earthworms as the microbial population is
Earthworm Survival Tactics in Flooding
How can earthworms survive many feet under water?
The Somerset Levels saw some of the worst flooding on
record in the UK last winter. (Press Association image)
Sampling for earthworms around a lake can
produce some interesting earthworm finds, such
as Eiseniella tetraedra. (V. Gilson photograph)
3
Earthworm News Volume 5, Issue 2 Winter 2014
News Hot Earthworm Topic
not destroyed. The flooding also deposits organic matter which is high in nutrients and
remains after the flood waters subside. There are some species such as Eiseniella tetraedra
and Allolobophora chlorotica (the green morph) that are found in waterlogged soils, such as
river banks.
Earthworm species are broadly split into 4 ecotype groups, using physiological and
behavioural characteristics. Different ecotype groups seem to
be able to tolerate flooding differently.
Anecic Earthworms
Anecic earthworms such as Apporectodea longa and
Lumbricus terrestris appear to be the least tolerant to
flooding, this is likely to be due to the interference that the
water has on the earthworms deep vertical burrows.
Endogeic Earthworms
Endogeic earthworms such as Allolobophora chlorotica and
Apporectodea rosea make horizontal burrows near the
surface of the soil. They tend to do better in environments
which have short term flooding, such as river banks and
edges of marshes. In cases of longer term flooding (soil
submerged for 2 months or more) endogeic species usually do
not survive. This could be due to the issues in burrowing;
similar to that of anecic earthworms. Though more studies
need to be done to confirm this.
In 1945 an Allolobophora chlorotica specimen was,
surprisingly found in sediment below Lake Windermere. The
species is known to breed in moist conditions however is
rarely found in permanently waterlogged soils.
Epigeic Earthworms
Epigeic earthworms such as Eiseniella tetraedra, Octolasion
lacteum and Lumbricus rubellus tend overall to be the most
successful earthworm group in flooded environments. This is
because they live on the surface of the soil, mainly in leaf
litter and do not make deep burrows.
Above: Apporectodea longa is an
anecic earthworm these species
burrow deep in to the soil and do
not do well in flood waters.
Above: Allolobophora chlorotica is
an endogeic earthworm.
Above: Lumbricus castaneus is an
epigeic earthworm, these species
are the most successful
earthworms in flooded areas and
actively live in very moist soils
(Images: NHM and FSC 2012)
4
It has been suggested that some species; such as Lumbricus rubellus; have adapted to
flooding through ensuring that the population can recover afterwards. This adaptation
appears to be early maturation of the species at a lower weight in floodplain areas, which in
turn allows L. rubellus to produce more cocoons. This is important because cocoons are
resistant to flooding and will hatch after the flooding has subsided allowing the population to
recover quickly. In studies into Eiseniella tetraedra there is a higher than average use of
cloning (asexual reproduction) to ensure the success of their species after flooding due to lack
of mates. Their cocoons like L. rubellus are resistant to water but also sink quickly in to the
soil.
E. tetraedra and O. lacteum survive well in water due to their ability to move their tails
upwards in the water to maintain gas exchange. This is in part done through increasing the
speed of osmoregulation (regulation of water within the body) to ensure their bodies do not
become over hydrated and die from water exposure.
Earthworms do not do well in heavily polluted flood waters. Heavy metal pollutants (such as
mercury and lead) appear to be one of the biggest problems in contaminated flood waters as
they are toxic and absorbed into the body. Therefore flooding in areas with a high
manufacturing history tends to have a lower population of earthworms than areas with more
rural or agricultural pasts.
Earthworm News Volume 5, Issue 2 Winter 2014
News Hot Earthworm Topic
Recent Publications
Written by Rachel Julie Clark
In April 2014 Natural England published a report about the
distribution, abundance and habitats of the Earthworms in
England. Their report was carried out by the Soil Biodiversity
Group at the Natural History Museum, London. The research
highlights the need for more sampling of earthworms across the
UK, to establish the conservation status of earthworms
particularly the ‘rarer’ species, such as Lumbricus friendi, and
Aporrectodea limicola.
You can download this publication at:
http://publications.naturalengland.org.uk/publication/5174957155811328
Written by Rachel Julie Clark
Further Reading:
Zorn, M. et al. (2008) ‘Flooding responses of three earthworm species, Allolobophora chlorotica, Aporrectodea caliginosa and Lumbricus
rubellus, in a laboratory-controlled environment.’ Soil Biology & Biochemistry, 40, 587-593.
Ivask, M. et al. (2012) ‘Effect of flooding by fresh and brackish water on earthworm communities along Matsalu Bay and the Kasari Riv-
er.’ European Journal of Soil Biology, 53, 11-15.
Zorn, M. et al. (2005) ‘Species-specific earthworm population responses in relation to flooding dynamics in a Dutch floodplain soil’ Pedobi-
ologia, 49, 189-198.
5
Earthworm News Volume 5, Issue 2 Winter 2014
ESB Field Meetings 2014
Recording
This year the Earthworm Society of Britain
launched our programme of field meetings. The
primary aim of the field meetings is to get out
into the field and collect earthworm records, but
also we are trying to recruit and train more
recorders who can go out and sample their local
areas and help towards getting more dots on the
distribution maps for earthworms in Britain.
During our field meetings we use ESB standard
sampling methods (see our previous newsletter,
Issue 5 Vol 1, or our website for the protocol) and
also look in some microhabitats such as dead wood, dung, hedgerows and leaf litter.
Most earthworms cannot be identified to species in the field and they need to be viewed
under a microscope to see the diagnostic features. On the second day of our field meetings we
hold an identification course, teaching attendees how to identify earthworms and then
identifying the specimens we collected the previous day.
We are proud to say that all three of our field meetings this year were a success and we are
currently planning 3 more for 2015 field meetings.
We would also like to say a big thank you to everyone who attended our field meetings and
made them such a success. We hope to see you at future events and look forward to receiving
more records from you.
Bracknell Forest Field Meeting - 22nd and 23rd March 2014
Reported by Kerry Calloway
Our first site; Garth Meadow, a
grassland that is used for pasture,
yielded 51 earthworms of 9 different
species. After our successes in Garth
Meadow we headed to the nearby
Tinkers Copse, a deciduous woodland
and nature reserve, where we found 4
species, 2 of which we hadn’t seen in
Garth Meadow, before continuing
to our last site of the morning.
The sampling team at the Bracknell Forest Field Meeting
Left to right Vicky, Ian, Dan, Rachel, Keith, Kerry, Keiron
and Emma (V. Gilson, photograph)
Rachel, Keiron and Kerry sampling at our first
site on our first field trip (V. Gilson, 2014)
6
Earthworm News Volume 5, Issue 2 Winter 2014
Recording ESB Field Meetings 2014
Larks Hill is a naturally regenerated grassland where we found
7 species before stopping for lunch.
After a picnic in the orchard we sampled 3 different sites in
Englemere Pond Nature Reserve: heath, woodland and pond
side and found very few earthworms here. This wasn’t
particularly surprising as the soil was very poor for earthworms
and much of the area was Pine forest. Pine trees make the
surrounding soils too acidic for earthworms so you generally
don’t find many living in these habitats. Sampling a site and
finding no earthworms is by no means a waste of time and it is
actually very interesting not to find any. A zero result can still
be added to the distribution map. We finished the day at Popes
Meadow and added a further 6 records.
The second day of the Bracknell Forest Field meeting was the
identification course which was successful, with everyone
greatly improving their identification skills and we managed to
identify most of the specimens collected on the previous day.
Special thanks to Keiron, Rachel and Salma for finishing off the identifications the following
week.
London Field Meeting (Richmond
Park) – 7th and 8th June 2014
Reported by Rachel Clark
We sampled eight sites in Richmond
Park, we had a rainy start to the day
which soon became a gloriously sunny
day. Our first site was acidic
grassland which was home to millions
of Yellow Meadow Ants (Lasius
flavus), each ant hill has between
8,000 to 14,000 individuals. We found
2 earthworms of different species. Our
second site was similar to site one,
acidic grassland, however was a mix
of grass and bracken. 8 earthworms
were found comprising of 3 species.
Emma showing us the art of
ESB sampling at Englemere
Pond (V, Gilson, 2014)
The sampling team at the Richmond Park Field Meeting
Back row L to R - Olivia, Michelle, Matthew, Rachel, Rus-
sell, Renee, Alex. Front row L to R - Kerry, Joanna and
Victoria (K. Brown, 2014)
7
Earthworm News Volume 5, Issue 2 Winter 2014
Recording ESB Field Meetings 2014
Our third site was neutral grassland, which can be identified due to the clover found in
the grass. 16 earthworms were collected comprising of 4 species. Our fourth site was also a
neutral grassland where we found 3 species. After a lunch break, with a lovely view of the
park, we headed to our fifth site. This was our most successful which was an acid grassland
with a small stream running through it, we collected 7 different species of earthworms from
this one site. We then went into a deciduous woodland, mainly of sweet chestnut and a
understorey of rhododendrons. This made for an interesting site, which was difficult to dig in
due to the roots and dense understorey, however, we
persevered and collected 3 different species. Site 7 was a Fen
on the edge of one of the ponds in the park, this site provided
the most individuals (18 in total), comprising of 3 species. Our
final site was an Orchard near the edge of the park with some
trees that were over 600 years old! Here we found 6
earthworms comprising of 3 species. In total, at Richmond
Park, we collected 15 species, 76 individuals.
Our second day was our identification course at the Natural
History Museum’s Angela Marmot Centre for UK
Biodiversity, we had a packed room and identified three ‘rare’
species; Allolobophoridella eiseni, Aporrectodea icterica and
Lumbricus festivus and one very rare species; Helodrilus
oculatus, however with all four of these species further
investigation is needed in order to verify their true
distribution and abundance in the UK.
We would once again like to say
a big thank you to everyone who
took part and we are currently
finalising the Capstone Farm
Country Park (Kent Field
Meeting) Report.
We will be announcing events in
the New Year, for people who
wish to
attend events in 2015.
Alex identifying earthworms at
the Natural History Museum
(R. Clark, 2014)
Some of our attendees of the Kent Field Meeting. Our report
will be on our website shortly (V. Gilson, 2014)
Written by Rachel Julie Clark and Kerry Calloway
8
ESB Preston Montford Field Meeting with the Field Studies Council
When: Sat, 21 March 2015 – Sun, 22 March 2015
Where: FSC Preston Montford, Montford Bridge, Shrewsbury,
Shropshire SY4 1DX
Day 1 will be field based and involve sampling a range of sites
and habitats. Experienced recorders will be on hand to provide
training and guidance to anyone new to earthworm recording.
The aim of the day is to introduce the method for sampling for
the National Earthworm Recording Scheme.
Day 2 will involve a lab-based identification course led by ESB
tutors and is suitable for those with no experience or those that
want to identify earthworms. Attendees are welcome to bring
earthworms from their own gardens or other places and we will
happily help with identification.
Upon completion of the course attendees will be added to the list
of recorders for the National Earthworm Recording Scheme. The
course fee is £15 and includes a one year membership to the
Earthworm Society of Britain, a copy of the AIDGAP Earthworm
key, ESB recording guides and sampling tubes.
To book a place, please email the course organiser (Keiron Brown)
Earthworm News Volume 5, Issue 2 Winter 2014
Events Events in 2015
Big Nature Day at the Natural History
Museum
When: Sat, 23 May 2015
Where: Natural History Museum, Cromwell Road
London SW7 5BD
The Earthworm Society of Britain will be
attending this year's Big Nature Day. Come along
and talk to our earthworm experts about these
fascinating animals. We will have activity sheets
for kids and our Earthworm Compost Survey
for adults. More details will be coming soon.
Kerry digging for earthworms
(V. Gilson, 2014)
9
One of our Trainee Identification
Tutors Kerry helping a student on
Kent Field Meeting Identification
Course
(R.Clark, 2014)
Earthworm News Volume 5, Issue 2 Winter 2014
Events Events in 2015
UK Earthworm Identification Workshop with
the Cumbria Biodiversity Data Centre
When: Tue, 23 June 2015, 10:00am – 4:00pm
Where: Tullie House Museum & Art Gallery, Castle St,
Carlisle, Cumbria CA3 8TP
Fee: £15 per attendee
A one day workshop, including sampling earthworms in the
field. The course fee is £15 and includes a one year
membership to the Earthworm Society of Britain, a copy of the
AIDGAP Earthworm key, ESB recording guides and sampling
tubes.
Book with Tullie House Box Office on 01228 618718.
Wildlife Training Workshop: Identification of
Earthworms with the Wildlife Trust for
Bedfordshire,Cambridgeshire and Northamptonshire
When: Sat, 14 November 2015, 10:00am - 4:00pm
Where: Lings, Northampton, Northamptonshire
This one day workshop is being run by the Wildlife Trust for
Bedfordshire, Cambridgeshire and Northamptonshire so
please check the events section of their website for more
details: www.wildlifebcn.org/whats-on
Two more field meetings are currently being
planned. The ESB Yorkshire Field Meeting will take
place in summer 2015 and the ESB Thames Valley
Field Meeting will follow in autumn 2015. Further
details will follow in future ESB Newsletters.
Dan identifying earthworms on the
Bracknell Forest Field Meeting
Identification Course
(V. Gilson, 2014)
Richard, Dan and Kerry
collecting earthworms on
the Kent Field Meeting
Sampling Day
(V. Gilson, 2014)
10
Earthworm News
The morphs of Allolobophora chlorotica
Species of the Season
Allolobophora chlorotica, ‘The
Green Worm’, is a widespread
earthworm living in a diverse
range of habitats; including,
probably, your own garden.
A. chlorotica is currently described
as one species with two morphs,
the green morph and the pink
morph. However, last year a team
at Cardiff University studied the
genetics of the two morphs and
their findings suggest there maybe
up to four different species rather
than one. In 2011, The Central Lancashire
University studied the DNA of the two morphs
and their data suggest the two morphs are
separate species. However more research needs
to be done to establish that they are in fact two
different species.
The two morphs do not only have different
colouration and maybe even genetics, but they
also live in different habitats. The pink morph
tends to live in gardens and woodlands, areas
that are damp but not very waterlogged. On the
other hand the Green morph tends to live in wetter conditions, such as grasslands, by
rivers and even under Lake Windermere (see ‘Earthworm’s Survival Tactics in Flooding’ page 2
for more information). Though both morphs do have the same distinctive clitellum and TP
(Tubercula pubertartis) consisting of 3 humps. The
clitellum and TP are reproductive organs and as a
result are only found on adult earthworms.
A. chlorotica is a widespread species. Its native range
spans across Europe through North Africa, Asia and
into Japan. The species, however, is now found in
North and South America, Africa and New Zealand after being
introduced by humans.
Allolobophora chlorotica is known as the Green Worm
because of its green colouration - though this is one of two
morphs (the other morph is pale pink/grey colour
(image - NHM.ac.uk, 2014)
The three distinctive
humps found on
adult A. chlorotica’s
clitellum
(image—NHM.ac.uk)
Allolobophora chlorotica the Pink morph
which is a pale pink/grey colour
(image - NHM.ac.uk, 2014)
Written By Rachel Julie Clark
11
The Velvet Worm is considered to be a missing
link between arthropods (e.g. insects and
arachnids) and annelids (segmented worms).
They may sound cute, soft and maybe even
cuddly, however, the Velvet Worm has a dark
side. It catches prey with slime and stabs its
jaws into the victims body to dispatch it.
The Velvet worm is scientifically known as
Onychophora which means ‘claw-bearers’. This
is due to the double claws they possess on the bottom of their stumpy, little legs. Velvet
worms have between 13 to 43 pairs of legs on a circular soft body. These little, stumpy-legged
creatures were the first animals to permanently walk on land - over 400 million years ago.
Velvet worms, unlike the humble earthworm, give birth to live young, which hatch from
their eggs inside their mother. This is known as ovoviviparity. After birth the young have no
parental care, showing, once more, the darker side of the velvet worm.
Velvet worms live in tropical countries; such as Central and South America, India, Australia,
Malaysia. Fossils of the velvet worm have been found in the Northern Hemisphere,
suggesting they inhabited further north during a warmer climate. Velvet worms live in dark,
damp environments such as leaf litter, rotting wood and stones, they even dwell in termite
tunnels. They are carnivorous, feeding on a range of invertebrates such as termites, woodlice
and spiders. They capture their prey by tangling them up in a sticky liquid that they squirt
out of a segment on their head, then suck the liquid out of the body of their prey. They also
use their slime as a defence mechanism.
Velvet worms such as Euperipatoides rowelli is
suggested to be a missing link between insect
and segmented worms (from NHM.ac.uk)
Written by Rachel Julie Clark
Tasmanipatus barretti (giant velvet worm) (left) is from Tasmania and Tasmanipatus
anophthalmus (blind velvet worm) (right) from Australia were classified in to a new genus in
1991 (images, NHM.ac.uk)
Earthworm News
The Truth About Velvet Worms
Curiosity Page Velvet worms, they are
called worms, so they
are closely related to
earthworms, right?
12
Earthworm News Volume 5, Issue 2 Winter 2014
Slime Time Puzzle of the Season
6
Complete this puzzle in two easy steps!
Solve the anagrams to get the clue
The Clue
1 4 5 2 3 6 7 8 9 10
11 14 15 12 13 16 17 18 19
A stocking filler?
The answer
We have found this fabulous little poetry book for
children on earthworms, written by Celia Warren.
This gem of a book not only has nursery rhymes and
poems on earthworms but little nuggets of
environmental and science education within them.
You can find the book on sale at the Bloomsbury
website for around £5.
You can buy it as a paperback or as an ebook.
TISH RAEMORTHR NAC VELI NI REFSH RATWE NAD MIOSEMSET NEOLSC FILEST
8 12
5
18
19 11
17
3 16 13
9 1
2 7
6
4 10 14
15
The letters in the numbered boxes, once put in order , will
reveal the answer.