By Mark Kinver
Science and environment reporter, BBC News
The population of mountain gorillas in the Democratic Republic of Congo's Virunga National Park has risen by 12.5%, a census shows.
It revealed that 81 gorillas were now living permanently inside the park.
In total, about 211 of the great apes were estimated to be currently residing in Africa's oldest national park.
It is the first census to be completed by the park's wildlife rangers since rebel troops seized control of the area in August 2007.
More than 50 rangers from the Congolese Wildlife Authority (ICCN) conducted more than 128 patrols during the eight-week census.
"Mountain gorilla family structures change with each birth, death, interaction and migration," explained ICCN gorilla monitoring head Innocent Mburanumwe, who writes a regular "gorilla diary" for the BBC News website.
"The Kabirizi family, our largest gorilla group with 33 individuals, has five newborns which is wonderful news," he revealed.
"But we are still hoping to locate the two gorillas from this same family that we have not yet seen."
During the 16-month period from August 2007 until January 2009, 10 baby gorillas were born into four of the habituated families.
However, three gorillas that had been previously identified in the August 2007 census have not been found and are listed as missing.
Trackers are able to identify individual gorillas because each animal's nose is uniquely patterned.
Significantly, no evidence of gorilla mortality was reported by the rangers, but they did discover and remove 536 snares laid by poachers.
"The status of Virunga's Mountain Gorillas is a triumph for conservation," said Emmanuel de Merode, Virunga National Park's director.
"It is the product of 15 years' effort and sacrifice on the part of Congo's rangers, (and the result) of the consistent support from international organisations and individuals, and of the sustained determination of three African nations to protect this globally important species," he added.
Mountain gorillas are listed as Critically Endangered, with only 720 remaining in the world.
About 380 of the animals are located in the Virunga Volcanoes Conservation Area (shared by DR Congo, Rwanda and Uganda), while a further 320 gorillas live in the Bwindi Impenetrable Forest, Uganda.
In recent years, the region has been gripped by conflict and civil war. Since August 2007, the gorilla sector of the national park has been under the control of rebel forces.
Until recently, officials had not been able to enter the area, and many of the 1,100 rangers had to flee to safety with their families.