Rare pink dolphins return to Hong Kong waters after coronavirus lockdown halted ferry traffic
- Sightings of vulnerable Chinese white dolphins have risen by 30% since March
- Boat and ferry travel were first suspended in the region in the same month
- With the lull in water travel, scientists have been able to study how the dolphins respond to noise
The Indo-Pacific dolphins – also known as Chinese white dolphins and pink dolphins – are moving back into parts of the Pearl River Delta off Hong Kong.
Their numbers have jumped by up to 30 per cent since March when ferry traffic was suspended due to the coronavirus lockdown.
Rare pink dolphins return to Hong Kong thanks to coronavirus lockdown halting ferry traffic on parts of the Pearl River Delta
Undated handout photo of two Chinese white dolphins in waters near Hong Kong. Dolphin numbers in the delta have jumped by up to 30 per cent since March, scientists said
The dolphins once avoided the area due to the boat traffic between Hong Kong and Macau.
Marine scientist Lindsay Porter, who has studied dolphins near Hong Kong for three decades, said: ‘What we have noticed since the ferries have stopped in this area is dolphins we hadn’t seen for four, five, six years are back in the Hong Kong habitat.
‘It seems very quickly that the dolphins have come back into this waterway.’
‘Normally this entire area would be full of fast ferries taking people from Hong Kong to Macau and back again,’ Porter added.
‘Since the Covid pandemic started in Macau and a lot of areas have had restricted travel, the fast ferries have stopped. And these waters have become very, very quiet.’
The lull in water traffic has given scientists a rare opportunity to study how underwater noise affected the dolphins’ behaviour.
From a small rubber boat, Porter and her team drop microphones into the water and use drones to watch for dolphins.
The research suggests the dolphins had adapted more rapidly than expected to the quiet environment, and the population was likely to rebound when such stressors were removed, Porter said.
Scientists think there are about 2,000 dolphins in the entire Pearl River estuary.
Marine scientist Lindsay Porter (pictured) said the lull in water traffic in the waters near Hong Kong has given scientists a unique opportunity to study how the dolphins respond to underwater sound
A Hong Kong government survey from 2019 found only about 52 dolphins entered the waters around the Asian financial hub, but Porter believes the real number may be slightly higher.
‘I sometimes feel that we’re studying the slow demise of this population, which can be really sad,’ she said.
Still, even if this population’s decline could not be stopped, the research could help other dolphin populations elsewhere, she said.
Hong Kong’s conservation plans have focused on opening marine parks, where ship traffic is limited but not banned. Three of those areas are frequented by dolphins.
The Hong Kong WWF, a conservation group, and Porter said such measures were inadequate as dolphins were still in danger of being hit by ferries as they moved between the protected areas.
‘It means that if we did have a comprehensive management plan in Hong Kong with more effective conservation measures, we might be able to quickly stop the decline in the dolphin population,’ she said.