As countries began lockdown regulations due to the coronavirus pandemic, animals have had some time of freedom from human activities. In Hong Kong, dolphins have returned to the waters after high-speed ferries ceased operations.
The Chinese white dolphins and pink dolphins or Indo-Pacific humpback dolphins are native to the Pearl River Estuary. These dolphins were first recorded in the area during the 1600s.
Before all the human activity, the dolphins stayed close to the shores of Hong Kong because they feed in shallow coastal areas. They typically avoid the waters between Hong Kong and Macau due to the number of high-speed boats in the area.
In partnership with the World Wildlife Fund (WWF) Hong Kong, they are working on detouring the ferries away from the dolphin populations when operations resume. Passengers would be charged a few dollars extra for the trip.
Human Activities Affecting Dolphins
WWF Hong Kong estimated that there are nearly 2,500 dolphins in the area, but there had been a rapid decrease of young dolphins in the waters. Threats to the dolphin population include water and noise pollution, overfishing, and coastal developments alongside heavy marine traffic.
Noise pollution has a tremendous impact on the dolphins since they rely on echolocation for communication, navigation, and hunting. The heavy marine traffic at the Pearl River Estuary has interfered with their echolocation and can cause serious injuries that affect their behavior.
The Agriculture, Fisheries, and Conservation Department has a long-term plan to monitor the dolphin populations and conserve the species via dolphin sanctuaries. However, the serious damage to their natural habitat has still contributed to their population decline, and human activity has disturbed their breeding and nursery areas.
READ: Bunkering Activity in Algoa Bay Are a Major Threat to African Penguin Populations
Dolphin Populations During the Pandemic
Ever since the pandemic decreased water traffic in the estuary, the dolphin population has increased by 30 percent since March. Dr. Lindsay Porter from the University of St. Andrews said that she's conducted regular surveys after Hong Kong and Macau both closed their borders and noticed more dolphins in the area.
Ferries traveling between the two cities were stopped in mid-February, Dr. Porter shared. "I've been studying these dolphins since 1993, and I've never seen anything like this dramatic change before, and the only thing that changed is 200 ferries stopped traveling before."
Along with her team, she borrowed a local yacht and boat to live in the open waters and study the large dolphin population. Dr. Porter shared that visual observations of the dolphins included them "spending much more time socializing, splashing around on the surface, quite a bit of foreplay, quite a bit of sex."
This was a very different behavior compared to pre-pandemic when the native dolphins lived at the edge of the waters. The stress from human activity, mostly from the ferries, caused the dolphins to spend most of their time eating and resting.
It was really great to see them increase in numbers, play more, and have a good time, she shared. The team also dropped underwater recording stations so they can compare the current vocalizations to data they had before the pandemic when the waters were full of traffic.
IN CASE YOU MISSED IT: Oil Drilling Will Continue in the Arctic National Wildlife Refuge
Check out more news and information on Wildlife on Science Times.
