how much does a giant otter weigh
1 Giant otters weigh about 200 grams (7 oz.) at birth. 2  Freshwater otter pups are born blind, toothless, and practically immobile. They remain in their birthing dens, and spend their first few weeks nursing and sleeping.  Sea otter pups measure 56 to 61 cm (22-24 in.) in length and weigh 2 to 2.3 kg (4.5-5 lb.). They are somewhat precocial; born with eyes open, first teeth already emerging, and a full coat of dense fur that enables them to float. They are, however, completely dependent on their mothers for care and protection.