The Pittsburgh Zoo & PPG Aquarium is purring with good news! Toma, our 12-year-old female Amur tiger, successfully delivered three cubs on Sunday afternoon. This is Toma’s third time becoming a mother.
Using an infrared camera inside the den, keepers were able to monitor Toma and witness the birth of the cubs. The cubs are blind, toothless, and rely completely on their mother. The first cub was born at 2:05 p.m. on Sunday. The second cub was born at 2:47 p.m. and the third one waited a bit longer and was born at 4:59 p.m.
“This morning, the cubs are still nursing and mom is very relaxed. Never one to miss a meal, she came out for breakfast and then immediately went back in to nurse the cubs,” says Kathy Suthard, lead keeper. Toma and the cubs are being monitored in their den via an infrared camera. Visitors will be able to see this video on a monitor set up at the tiger window. The cubs will not be out on their yard until they are big enough to navigate the moat.
Several milestones must be reached to ensure successful birth and development of tiger cubs. Their first movements should be to nurse.
“We are very pleased because they are nursing and Toma is nurturing them, much like we saw with her first litter,” says Dr. Barbara Baker, president and CEO. “We are monitoring Toma and the cubs to ensure this continues and that the cubs are gaining weight. Eventually we will have the opportunity to weigh them, but we will not interfere with her raising them as long as they are thriving.”
Amur tigers are classified as critically endangered, with an estimated population of less than 400 individuals remaining in the wild.
“The mortality rate of cubs in the wild and in captivity is between 30 and 40 percent and even though Toma has had two litters before, we are taking every precaution,” says Ken Kaemmerer, mammal curator. Toma delivered three cubs in August 2006. The smallest cub died five weeks later, but she raised the other two. In 2009, she gave birth to one cub, Billy Ray, which for reasons still unknown, she rejected him. He was hand-raised by staff. Billy Ray now lives with a female at the Cheyenne Mountain Zoo in Colorado Springs.
In late May, Toma entered her breeding cycle and successfully mated with 11-year-old Taiga. “A couple weeks later, we suspected that Toma might be pregnant based on her behavior,” says Mr. Kaemmerer. “She became very easy going and not as pensive as usual. A few days later, our suspicions were confirmed by the results of her hormone test.” The two were paired under recommendation of the Association of Zoos and Aquariums (AZA) Species Survival Plan (SSP) which ensures healthy populations and genetic diversity among zoo animals. Fortunately, Toma and Taiga approved of the match. Average gestation for tigers is 103 days. Toma’s last two were 105 days. This one was 104 days.
Amur tigers were once called Siberian tigers because originally they were found throughout Siberia. They are now almost completely confined to the Far East portion of Asia along the Amur River. Amur tigers are the largest member of the cat family. They can grow to nearly four-feet-tall and more than seven-feet-long.