The Times - UK (2022-06-13)

the times | Monday June 13 2022 15

News

Cat owners should keep their “murder-
ous” pets indoors, particularly around
sunset and at night, to protect birds and
bats, experts advise.
Several speakers at the Cheltenham
Science Festival, experts on birds,
biodiversity and domestic pets, said
independently that cats could wreak
havoc on garden wildlife.
Beth Gerrard, of the Bat Conserv-
ation Research Lab at the University of
West England, gave advice to people on
how to protect bats in their gardens.
She said cat owners could keep their
pets in at night. “If you can’t keep them
in all night, you could keep them in
from half an hour before sunset to the
hour after sunset,” she said. “That can
make a really big difference.”
She said that “extravagant-looking
collars”, including a rainbow-coloured
ruff, could be put on a cat to warn away
birds. These had not been tested on
bats, however, she said.
Figures suggest that cats kill about
250,000 bats and 27 million birds in the
UK each year. The UK has 18 native
species of bat and many are increasing
in number, especially those that make
their homes in abandoned buildings
and thrive in urban areas. But species
that are more sensitive to light and
noise are in trouble.
Four species are classed as being at
imminent risk of extinction: the greater
mouse-eared, grey long-eared, serotine
and barbastelle bats. A further two spe-

cies are classed as “near threatened”:

Leisler’s bat and Nathusius’ pipistrelle.

Gerrard said that people wishing to

encourage bats into their gardens

should try to prevent light spillage from

their homes.

They should shut their curtains and

consider using blackout blinds. They

should also turn off garden lights at

night and ensure that their security

lights are motion sensitive rather than

on permanently.

Gardeners should allow their gar-

dens to go “a little bit wild” to encourage

the insects that bats rely on for food.

People should avoid using pesticides

and eat organic food, both of which pro-

tect insects.

In a separate talk, entitled Gardening

to Save the Planet, Dawood Qureshi, a

researcher at the BBC Natural History

Unit and an ambassador for the Bum-

blebee Conservation Trust, said that

Lock up your koi carp, the

ravenous otters are about

Peter Chappell

It is a mystery with all the ingredients of

a classic Agatha Christie tale. A victim

known for being at home in the gardens

of Britain’s grandest houses is left

bloodied by the side of pool, the motive

not immediately apparent.

Such a whodunnit is puzzling koi

carp owners across the country, and the

culprit has now been identified by the

police as one of Britain’s best-protected

residents: the European otter.

The UK Wild Otter Trust, a charity

in North Devon that holds the coun-

try’s only licence to trap and remove

otters, has said that the species could

wreak havoc and “cause massive finan-

cial issues” if they invaded ponds.

Dave Webb, the founder of the char-

ity, said that its workers had been called

out to people who had kept fish for

years in a garden pond, and “an otter’s

come in and taken them”. He added:

“And then we’ve been to other places

that are, you know, fanatical koi carp

keepers with ponds the size of a swim-

ming pool, and an otter’s got into that.”

Kath Webb, his wife and an employee

at the trust, said she had seen such otter

attacks increase over the past five years.

“Once it finds the source of food, it will

keep coming back until they’re all

gone,” she said. “Sometimes we advise

people to move them out of the pond

and put them somewhere safe.”

Mr Webb suggested that changes to

working habits could be driving the

change. “Now more people are having

garden ponds because more people are

working from home because of Covid,”

he said. Heavy rainfall and wintery

conditions also raised water levels and

strengthened currents, making attacks

more likely, he added. “They then come

inland a little bit away from the danger

of that fast-flowing river and they stum-

ble across garden ponds, and quite

often gardens are not secured to keep

an otter out... the fully sized otter can

get through a gap of four inches.”

Last week Wiltshire police told pond-

owners to protect their fish but Mr

Webb criticised the force for not stating

that trying to “disturb, trap or kill” an

otter could lead to an unlimited fine

and up to five years in prison. Otters

had “the highest level of protection of

any species in the country”, he said. “I

get the frustration from garden pond

owners because koi carp can be ex-

tremely expensive... However, when

they go out shopping, they don’t leave

the front door wide open... with a wal-

let inside so they shouldn’t do it with a

pond. They need to be mindful that the

only legal proper solution is to protect

the garden pond.”

In Pewsey, Wiltshire, close to the

Kennet and Avon canal, Leo Pocock

awoke to find that otters had got into his

garden during the night and attacked

four koi carp. “I’ve been keeping fish for

at least 25 years and have never seen an

otter until now. They took an 18-inch-

long shiro utsuri, a type of black-and-

white carp worth hundreds of pounds. I

lost £1,500 worth of fish but it isn’t about

the money. I’ve had them since they

were tiny and I see them and feed them

twice a day, like you would a cat.”

Anna Ford, of Action for the River

Kennet, said: “We’re very lucky to have

otters on the Kennet. They are a native

apex predator, so at the top of the food

chain, and part of the river ecosystem.”

Keep killer cats indoors

at night to save wildlife

Kaya Burgess Science Reporter cats were “an animal that you don’t
want hanging around the garden too
much”. He said: “I do think you should
keep cats inside. I don’t really think that
they’re very useful for our environment
and our wildlife.
“I know it’s a bit hard because they
are everywhere. A lot of the time [they
are] hunting for fun... They’re killing
off bird life.”
In a third talk, Catology v Dogology,
Stefan Gates, an expert on both pets,
said cats had a negative and positive im-
pacts on birds. “They are quite murder-
ous and they do kill a lot of birds,” he
said. “There’s a big debate going on over
whether cats are good or bad for the en-
vironment.
“They kill millions of birds a year but
they also kill a lot of rats and rats are the
main species that predates on birds. It’s
a very difficult balance.”
An RSPCA spokeswoman recom-
mended “restricting outdoor access”
for cats at dusk and dawn when wildlife
was most active.
She added that other measures, such
as collars with bells, keeping bird feed-
ers out of reach of cats and reducing
spillage from the feeders, could help to
protect birds.
“Predation on wildlife is likely to
cause considerable suffering, which is
of course concerning to both animal
charities like ourselves and many cat
owners too,” she said. “However, re-
stricting a cat’s natural behaviour can
also have detrimental impacts on their
individual health and wellbeing.”

Cats kill about 27 million birds and

250,000 bats a year, experts say

B

aby parrots

learn to

communicate

by softly

babbling

nonsense sounds to

themselves, in a similar

way to human infants

(Rhys Blakely writes).

The research, carried

out in the jungles of

Venezuela, is said to be

the first to document

how the baby birds

repeat the medley of

calls that they hear from

their parents and other

adults in the wild.

The resulting

squawks, peeps, whistles

and growls carry no real

meaning. The process

mirrors the way in

which human babies

develop their

conversational skills by

combining basic

syllables in gibberish

sentences, the

researchers said.

“These parrots are

basically kind of

regurgitating everything

they’ve heard from their

own species,” said Dr

Karl Berg of the

University of Texas Rio

Grande Valley, who led

the study.

“They’re able to filter

out the other noises of

the jungle and focus on

their own species, but

it’s a medley. You get bits

of begging calls, alarm

calls, the calls that males

and females use to

defend nest sites.

“There are contact

calls, which are very

important in the species,

which function like

names. But it’s all

jumbled together and

doesn’t make any sense.

It’s lacking a

behavioural context.

And that is typical, too,

of babbling baby

humans.”

Berg and his

colleagues monitored a

dozen nests of green-

rumped parrotlets,

which are found in

tropical South America.

The babbling noises

began when the

parrotlets were about 21

days old, and the

researchers counted 27

different sounds.

Most chicks started

babbling when their

siblings were asleep and

their parents were away

from the nest, and often

made sounds without

opening their beaks.

“It’s kind of a tossed

salad of just about

everything that the birds

have heard up to that

stage in their life,” Berg

said. Cortisol, a stress

hormone, is thought to

play a key role in the

development of speech

in infant humans. It also

appears to be important

for the parrots. The

birds that received a

small dose of the

hormone as part of the

study increased their

call repertoires

compared with those

that did not.

The research took

place at the Masaguaral

Biological Station in

Venezuela, where the

parrots have been

studied continuously

since the 1980s, making

it the longest-running

research project of its

kind. Green-rumped

parrotlets are relatively

common, but their early

vocal habits appear to

have slipped under the

radar until now.

“Despite widespread

availability as pets and

for laboratory research,

a vocal babbling stage in

development has gone

unnoticed in this group,”

the researchers said in

the study, which is in the

Proceedings of the Royal

Society B.

A tantalising discovery,

leading article, page 29

Babysquawk is the

secret to learning

parrot fashion

Talk on the

wild side

Bird songs are not

innate but learnt by

chicks from their

parents. Research

suggests that in some

birds, calls are taught

to chicks even before

they are hatched.

Baby dolphins also

“babble”, in their case

with clicks and

whistles. These sounds

are, like baby babbling,

part-formed versions of

the real thing.

Lion cubs are not

able to roar until past

their first birthday. This

is because the vocal

cords have to change

shape to produce the

110 decibel roar. But it

does not stop them

practising the vital skill,

with what initially

sound like squeaks.

Rhesus macaques

interact with their

babies with

exaggerated facial

expressions, just like

human mothers, in this

case mutual lip

smacking.

KARL S. BERG

Green-rumped

parrotlets learn to

communicate by

repeating the calls

they hear in the wild