A Longman's beaked whale that was injured and later died after being stranded in Tai O may have been hurt or unwell before entering Hong Kong waters. The Agriculture, Fisheries and Conservation Department of Hong Kong had activated a rescue plan upon sighting the whale near Tai O. Longman's beaked whales, also known as "tropical bottlenose whales" or "Indo-Pacific beaked whales," are among the rarest and least understood members of the beaked whale family.

Typically, Longman's Indo-Pacific beaked whales inhabit the deep offshore waters of the Indian and Pacific Oceans, avoiding shallow coastal areas and rarely venturing into Hong Kong waters. "By the time we observed the animal in the evening, it was already very weak and not exhibiting normal behavior," said by Taison Chang, chairman of the Hong Kong Dolphin Conservation Society.

A 2021 academic article published in Japan highlighted that Longman's Indo-Pacific beaked whale is one of the rarest whale species globally. Since its classification in 1926, only 17 strandings have been recorded. The International Union for Conservation of Nature (IUCN) Red List of Threatened Species indicates that information about the population and distribution of this species remains largely "unknown."

Due to their rarity and limited strandings, there are only a few specimens of Longman's Indo-Pacific beaked whale. Notably, a specimen discovered in Okinawa, Japan, in 2011 was prepared and displayed at the Okinawa Churaumi Aquarium. As of June 2021, this specimen remains the only complete skeleton of a male Indo-Pacific beaked whale in existence.