Page 11 - BBC Wildlife Volume 36 #05

WILD SPRING

Hidden

s a boy I collected pond
life and proudly exhibited
Amy micro-aquaria in my
parents’ shed. I kept my charges
in a carefully curated assortment The lesser
of jam jars, tubs, tubes and water boatmen
tanks. One quiet evening I heard NICK in your local
pond have a
a determined buzzing. After a sonic secret.
bit of triangulation, I discovered BAKER
the rasping was emanating from REVEALS A
hear a recording made for an
a ‘jamming’ jam jar. Inside were h
pisode of Radio Four’s Nature
water boatmen. FASCINATING ep
I had just become aware of a WORLD OF If onl yy I had known then s eries (g (go to www.bbc.co.uk/ /
secret world of insect acoustic WILDLIFE THAT what I know now: several of p rogrammes/b0194mvq).
ecology. My lively pond bugs the smaller specimens in my Normally, loud noises go with
were singing like crickets. I’ve WE OFTEN aquatic zoo were also singing, b ig animals, and blue whales
nd African elephants are indeed
since heard water boatmen called OVERLOOK. albeit in a very different way. an
‘water crickets’ in North America, Any pond dip can turn up lo
ouder, at 188 dB and 117 dB
and while they use different many different but related re espectively. But if you scale
parts of their bodies to produce WAT E R species of water boatmen. u
up the efforts of M. scholtzi,
their scratchy tunes, the method B OAT M E N However one family, the it t is the loudest animal in the
world for its size. What nobody
is similar. Rubbing bits of the Micronecta, stridulate not with w
u
body together to create sound is their legs but with their penis! understands is how it can be so
known as stridulation. One common species, the lo
oud, or why it needs to be.
Most of my captives were 2mm-long Micronecta
lesser water boatmen, which are scholtzi, has been L oud and proud
abundant and widespread. Close D I D YO U studied in great I t t is thought that these bugs
might use the bubble of air
scrutiny of them singing revealed K N OW ? detail. The male m
hat they clutch to their bodies
they did it by moving their front Insects aren’t the only rubs a ridge on its th
legs, which bear rows of tiny ones to stridulate. penis against ridges e ev verytime they visit the surface
stiff pegs, against a ridge on Madagascar's streaked on its abdomen, a s a kind of resonator, but the
their head. It was a slow stroking tenrec rubs its quills thereby setting ex xact mechanism has acoustics
ngineers baffled. If we ever
at first, warming up to a rapid together to make the pond – and any en
sound.
u
vibration when in full flow. The female in it – abuzz. uncover the secret it may have
i
sound was impressive given the M. scholtzi has been useful applications in ultrasonic
u
insects were just 1cm long. recorded generating 99.2 sy ystems. As to why these
nsects need to be so loud, some
decibels (although it usually in
sings around 78.9 dB), and this b iologists think it is down to a
GOOD VIBRATIONS acoustic accomplishment is all s exual selection process that has
un away with itself.
the more incredible given the ru
Many other insects generate sound by friction.
stridulating organ is fewer than With the males competing
s
q
ns
e
ect
epetitiv
Quite a few pond insects s r repetitive squeak, like someone 50 micrometers across – about fo or females by engaging in
ustrat ons by Peter Dav d Scott/The Art Agency (pictured), which rub their strid r ract mates, includingg around clutching our bleeding su
su
ub-aqua sing-offs, the loudest
the width of a human hair. The
walking in a
stridulate. My favourites are the
o
pair of new shoes.
reason we’re not all stumbling
ar
re most often selected. In the
bumbling little screech beetles
er invertebrates
e
Many othe
ub-surface world of the pond,
o
ulate in defence or to
here are apparently no predators
th
ears is that the water itself
att
wing-cases against their
hat hunt by sound. And with no
th
absorbs nearly all of the energy.
ickets, spiders,
cr
abdomens when uupset
And yet, if you’re tuned into the
e
cological compromise, there is
mantises, beetles,
m
by predators or heavy-
sound, it’s possible to sit by a
n
no disadvantage to being so loud
an
nd butterflies. But
handed pond dippers.
a
nd singing your socks off.
hear the chorus. Or visit BBC
is not so much a
o
n
nly others that use
NN
iPlayer Radio, where you can
screech as a kind of
heir genitals.
th
o
a naturalist, author and TV presenter.
is
I The noise they make py yralid moths are the pond when it’s quiet and actually an ICK BAKER
Spring 2018 BBC Wildlife 11