Cuddliest twins in the jungle: Young gorillas get a hug from Mum after a busy day exploring the forest

• Mountain gorilla Kabatwa went forest walking with her five-month-old twins
• Isango and Isangano are fifth set of gorilla twins born in Rwanda in 40 years
  

By David Derbyshire for MailOnline

Published: 20:27 EDT, 20 March 2013 | Updated: 03:28 EDT, 21 March 2013

Twin babies might be hard work for their exhausted mothers – but all that effort is worth every second when it’s time for a cuddle.

These delightful pictures show Kabatwa, the proud mother, drawing her youngsters to her during a Rwandan rainforest downpour - less ‘Gorillas in the Mist’ than gorillas in the deluge.

With fewer than 900 mountain gorillas left in the wild, the birth of twins is particularly exciting for conservationists as well as for their mother.

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Help, Mum, it's starting to rain: Her hair matted by the deluge, Kabatwa her long comforting arms around her boys. It's been an exciting day but soon it will be time for bed

Let's go exploring: Hand-in-hand, Isango and Isangano discover the delights of their forest home

Mountain gorillas have babies only every four or five years and twins are extremely rare. This pair are only the fifth set recorded in Rwanda in 40 years.

They are called Isango (which means ‘Appointment’) and Isangano (which means ‘Crossroad’) -  the Rwandans favour what we would think of as unusual names for gorillas - there are others called ‘Word’, ‘Known’, ‘Advisor’ and ‘Greetings’.

Isango and Isangano – pictured here at five months – were born in 2011. The family belong to a group of nine gorillas known as the ‘Hirwa’ (‘lucky one’) group, living in the Parc National des Volcans (Volcanoes Park), Rwanda.

Gorilla mothers invest huge amounts of time and love in their offspring. The babies are born helpless, with their eyes tightly shut.

For the first three to four months, they cling to their mother’s chest 24 hours a day while she spends long periods stroking, touching and kissing them.

After four months, youngsters are able to sit up and to stand with a helping hand. Soon afterwards they begin to crawl and start to explore the forest floor – and the other members of the group.

When these pictures were taken, the twins were just starting to become more independent.

Hold on tight: The big wide world can be a scary place for these brothers

They were old enough to cadge piggy-back rides from Mum and to enjoy playing with other babies or even adults.

Mountain gorillas – who are shaggier than their lowland cousins - live in family groups of up to 30, with typical groups containing 11.

They are led by a dominant male silverback, who is fiercely protective of any babies. Any member of the group will defend the youngsters if they are attacked or threatened.

David Hewitt of the UK charity Gorilla Organisation said: ‘For the first few months infants cling to the mother all the time so they are under her watchful eye. But once they begin to get more active and start exploring they can be in greater danger.

‘A major threat comes from snares put out by poachers to trap antelope and other bush meat. The babies get entangled in the snares.

‘They can also get in the way when two adult males get rambunctious.’

However, the males are usually tolerant of youngsters. Although a silverback will rarely play with a baby, it will happily allow an infant to clamber over its back.’

A helping hand: Mother gives two of her boys a piggy back while on their forest adventure

The mothers nurse their young until the age of two and the infants sleep with Mum in nests made of twigs and leaves until they are three.

Females reach sexual maturity aged six, when they can weigh up to 300 pounds. However, these boys will not be sexually mature until 10 when they will weigh around 500 pounds. Mountain gorillas can live for 30 to 35 years in the wild.

Of all the great apes, gorillas are the best at looking after twins. Chimpanzee and orangutan twin births usually result in one baby dying within two weeks.

Mountain gorillas are on the verge of extinction, and are threatened by the loss of forests for farming and firewood and bush meat hunting.

However, numbers have increased in recent years after a concerted conservation effort, funded in part by wildlife tourism. In the late 1960s there were fewer than 600 mountain gorillas.

Around half of the world’s mountain gorillas live in the rainforest in the mountains of the Virunga volcano chain, straddling the borders of Rwanda, the Congo and Uganda.

The area was a base for Dian Fossey, the gorilla expert murdered in 1985 whose memoir ‘Gorillas in the Mist’ was a hit film starring Sigourney Weaver.

A quiet moment: The mother takes a moment to herself and watches her boys playing in the forest

VIDEO The progress of the adorable pair is monitored by local doctors in the area