MUMBAI: Barely a week after it was hatched at the Veermata Jijabai Bhosale Udyan va Pranisangrahalaya popularly known as Byculla zoo , India's first Humboldt penguin died on Wednesday night.A postmortem done by a team of professors from Parel’s Bombay Veterinary College on Thursday revealed “new-born anomalies like yolk sac retention and liver dysfunction” as the cause for the chick’s death.This is the second death of a penguin at the Udyan in two years. Of eight Humbolt penguins brought in 2016 after Shiv Sena leader Aaditya Thackeray’s push for hosting them at the BMC-run zoo, one had died within three months even as wildlife experts and several citizens criticized the move to relocate the South American birds from a South Korean zoo.The veterinary team on Friday issued a note stating the parents 'Mr Molt' (male) and 'Flipper' (female) "were taking good care of the chick and its development was proper, however as a matter of surprise the chick was found to be sinking on August 22." They added that despite the team’s efforts, the chick was found dead the same night.Zoo director Sanjay Tripathi told TOI, "It was a birth anomaly. The first 30 days for first-time penguin parents are crucial. Penguin eggs and chicks show 60% mortality. In this case there were complications that developed suddenly and since it was all internal, we did not know until Wednesday when it deteriorated in 12 hours. There was drastic reduction in its activity. It showed dullness and the vets tried to feed it forcibly because overnight its weight had dropped by around 15 grams. We realized it was gone when it stopped making movements and chirping sounds."Tripathi added, "I was there during the postmortem and saw how the gall bladder had dilated, green stains from the bile retained in the gizzard and how that had affected other organs."After mating in captivity, Molt and Flipper had delivered an egg that was much celebrated by animal lovers who circulated its photograph, clicked in a protected atmosphere. A healthy 75 grams at birth, its weight had increased to 97 on August 21. It's sex had not been determined and it was not open to viewing by the public as zoo authorities had said it needed to be kept in the secluded nesting area for a few months.The chick was cremated on Thursday evening at the zoo’s botanic garden.Although a scientific paper titled ‘Artificial incubation and hand rearing of Humboldt penguins’ that the vet report cites claims 30-35% mortality rates for chicks less than 30 days old and adds that the first three months are crucial for survival, activists slammed the BMC for what they called a deceptive justification.