Baikal Seals (Pusa Sabirica) are the worlds only species of fresh water seals. The ancestry of this species is debatable, though many believe they are derived from Ringed Seals, the two becoming geographically isolated some half a million years ago. A study conducted in 2000 revealed the population is rapidly decreasing with pup mortality increasing three fold. DDT, organochlorines and other chemical pollutants pose a severe threat within the lake. Having spread throughout the food web, these chemicals build up in the seals and results in compromised immune systems. Due to these pollutants, in 1987 some 8 000 seals died from distemper virus, believed to have been transmitted by domestic dogs.
BREEDING HABITS OF BAIKAL SEALS
From February to March, pupping will take place out on the ice of Lake Baikal. As with the Ringed Seal, this species will also dig itself a lair which has been hollowed out of the ice.
Pups weigh in at around 4kg and measure +/- 65cm at birth. They are born with a whitish coat which they shed when they are around two months old. As the animal matures, it will develop its adult coat, characterized by its dark silvery grey back with lighter yellowish chest.
The weaning period for these animals is around 2.5 months. However, on the Southern part of the lake, the ice tends to break up earlier resulting in a shorter weaning period. Consequently animals from this region tend to be smaller.
Mating takes place in the water, with adult males reaching sexual maturity at between 4-7 years and females at between 3-5 years. Gestation periods are approximately 11 months.
Adult males weigh around 65-70kg and measure +/- 1.3m in length while adult females are only slightly smaller. Sexual dimorphism in this species is not as apparent as in some of the other pinnipeds. They can live for an exceptionally long time, over 50 years.
- These animals are found exclusively in Russia’s ‘Lake Baikal,’ the largest, deepest and oldest body of fresh water on earth.
- They are known to be preyed upon by Brown bears.
- They are also known as “Nerpa.”
- They tend to be a lot more graceful than other seals, especially the females.
- They have an additional 2 liters of blood. This enables them to hold their breaths for up to 70 minutes!
- They can dive to a depth of 400 m.
Females can give birth to over 20 young during the course of a lifetime.
Baikal Seals will feed almost exclusively at night, using their vibrissae to locate potential prey.
Adults will consume between 3-4 kg of food each day. This equates to over a ton of food per seal in a year.
Their total population is estimated to be around 60 thousand.
Only pregnant females will haul out during the winter. Males will remain in the water tending to their breathing holes.
This is one of the few species of seal known to give birth to twins. The twins will often remain together even some time after weaning.
These seals are blamed for a drop in numbers of “omul.” ( a type of fish found in Lake Baikal) This is not the case. Baikal’s main source of food is the fish “golomyanka” and by eating tons of these fish each year, they cut down the omul’s competition for resources, thus actually doing the species a favour.