Exploring the hidden biodiversity of Macao

TEXT David Gonçalves, Dean of the Institute of Science and Environment of University of Saint Joseph

With an area of about 30 square kilometres and a population density of more than 21,000 inhabitants
per square kilometre, it is hard to imagine that Macao still retains any significant biodiversity. Yet amongst the high‐rise buildings, glittering casino lights, and bustle of tourists and locals, nature finds its way.

Unnoticed to the untrained eye, birds of prey soar above buildings, medicinal plants blossom in urban parks, and dolphins frolic in waters near the airport lane – a wondrous world just waiting to be discovered. All you need is a guide.

We start our tour in the centre of Coloane, a village located on the greenest of the three islands of Macao. Emerging from the shadow of the large, exotic fig trees (Ficus rumphii) that line the central square of the village, we approach the river channel with Zhuhai, in mainland China, just a few hundred metres in front of us.

Standing still during low tide, we watch as the mudflat comes alive. Small, red bowed fiddler crabs (Uca arcuata) start to emerge from their burrows. Males, wielding one enlarged claw that can weigh up to 40 per cent of their total body weight, wave their claw in synchronous movements to try to get the attention of females. Apparently unimpressed by the males’ efforts, they continue feeding on the microalgae film that grows on the surface of the mudflat.

Just behind them, two male great blue‐spotted mudskippers (Boleophthalmus pectinirostris) – remarkable fish that can walk on land and breathe air – fight with spectacular displays, spreading their fins and pushing each other mouth­ ‐to‐mouth. Another male mudskipper jumps high in the air, trying to stand out from the dull background in the hope of catching the females’ attention.

A bit further away a Chinese pond heron (Ardeola bacchus), one of about 200 species of birds that can be found in Macao, patiently waits for an opportunity to feed on them. As we stand up, life quickly disappears below ground and we move on to our next stop: the walking trails of Coloane hills.

Circling Coloane

The Coloane trail stretches 8,100 metres around the central part of the island. Soon after we set out, a barely audible sound at head level calls our attention. Hidden among the vegetation, a green, venomous white‐lipped pit viper (Cryptelytrops albolabris), one of the 16 snake species described for Macao, quietly slithers away, probably disturbed by our presence.

A few more metres and a large red‐bellied tree squirrel (Callosciurus erythraeus), introduced to Macao long ago, feedson red flowers on the branch of acotton tree (Bombax ceiba). These squirrels also feed on birds’ eggs, making them a threat to native birdspecies. Just below, the flashlight of a mobile phone reveals a banded bullfrog (Kaloula pulchra) hiding in a hole of the soft rock.

The trail is generally dry but in one of its few small ponds a spot‐legged tree frog (Polypedates megacephalus) clings with its fingerpads to a leaf from a lotus plant (Nelumbo nucifera), symbol of the city of Macao featured prominently on the city flag.

Among the numerous and varied butterflies observed during our walk, one laying in the shadow of a Chinese hackberry tree (Celtis sinensis) calls our attention with its impressive size and beautiful colours. It is actually not a butterfly but a Chinese moon moth (Actias ningpoana), one of the largest moths in the world. We are very lucky to spot one: Chinese moon moths only live 10–12 days to mate and reproduce, dying right afterwards.

Just beside it, a giant golden orb weaver (Nephila pilipes) hangs from its 2 metre‐wide web. Although inoffensive, these threatening looking spiders are certainly impressive. After 30 minutes walking, it’s time for a break. Sitting on a huge granite boulder overlooking Hac Sa Beach, we grab our binoculars and watch as a large black kite (Milvus migrans) glides effortlessly through the air, scanning the area in search of prey.

Still looking through the binoculars, a splash in the water calls our attention. After some minutes searching, we find its source: a group of 6‐8 Chinese white dolphins (Sousa chinensis) periodically surface to breathe, just a few hundred metres from the shoreline. The group, composed of adults and at least one juvenile, display frequent behaviours at the surface that sometimes expose their long beaks.

The Pearl River estuary hosts the largest population in China of this species, but its numbers are under strong decline, threatened by fishing nets, heavy marine traffic, habitat destruction, and environmental contamination. We lose sight of Black‐faced spoonbill (Platalea minor) the dolphin group and decide it is time to finish the trail and move on to our next stop: Cotai, the landfill reclamation area that unites the islands of Coloane and Taipa, home to the larger resorts in the territory.

Hidden wildlife in the casino jungle

Exiting Coloane, we pass the Seac Pai Van Park on our right, a zoo‐like area home to a number of captive animals – giant pandas, red pandas, rare primates, and birds – and an interesting collection of plants used in traditional Chinese medicine. With time running short, we turn our attention back to the local wildlife.

It seems like we won’t find much, standing in sight of the Cotai Strip, a replica of the Eiffel Tower emerging amid the high‐volume resort buildings. Cotai and Taipa may be much less green than Coloane, but there are still a few interesting places left to visit in search of local animals and plants.

These include the hiking trails of the Small and Big Taipa Hills, the wetland in front of the Taipa Houses‐ ‐Museum and the Cotai Ecological Zones I and II, the latter established by the government of Macao in 2003– 2004 to promote environmental education and conservation.

We choose to use our remaining time together to visit the Cotai ecological zones, managed by the Macao Environmental Protection Bureau. We begin with a guided tour of Ecological Zone I, 15 hectares of fenced wetland used as a foraging and resting place by many species of migratory birds.

With the casino buildings in the background, we hit jackpot, spotting the most iconic bird species of Macao: the black‐faced spoonbill (Platalea minor).

Water circulation between the inner waterways and the adjacent river course allow fish, crustaceans, and other aquatic species to enter the zone. Small islands with planted species of mangroves, reeds, and shrubs complete this interesting ecosystem, and provide a valuable place for birds to rest and hide.

We enter one of the four wood‐ ‐built observation stations where we can eavesdrop on the local fauna without disturbing it. With the casino buildings in the background, we hit jackpot, spotting the most iconic bird species of Macao: the black‐faced spoonbill (Platalea minor).

This species is listed as endangered on the International Union for Conservation of Nature (IUCN) Red List of threatened species due to its very small population of slightly over 3,300 individuals. In spite of continued threats such as habitat destruction, the population seems to be bouncing back after hitting a low of 288 animals in 1988.

Black‐faced spoonbills winter in coastal areas between Taiwan and Vietnam, and reproduce in only a few sites in Liaoning province and along the west coast of the Korean Peninsula. The few birds we see will soon be leaving for those breeding areas. It is certainly a privilege to be able to observe these rare birds in Macao.

With our binoculars and the help of our guide, we identify 15 additional bird species during
our short visit. We give our place in the observatory to a group of children from a local primary school and start our short walk to the Ecological Zone II.

This open area of 40 hectares sits on the river margin overlooking Hengqin island. Its larger mangrove ecosystem boasts high levels of biodiversity and serves as breeding and nursery grounds for many species of crustaceans, fish, and birds.

We join various bird watchers and photographers to peek through a small opening in the tree canopy that lines the cycle lane adjacent to the ecological zone.

A few dozen metres from us, apparently indifferent to our presence and the continuous sound from the camera shutters, a pair of little egrets (Egretta garzetta) begin preparing their nests for the approaching breeding season.

Other species of herons and egrets, such as the grey heron (Ardea cinerea), the great egret (Ardea alba) and the black‐crowned night heron (Nycticorax nycticorax) are in sight, often fighting for
space in the mangrove canopy. Observing the natural behaviour of these majestic birds at such close distance is fascinating and we lose Little egret (Egretta garzetta) track of time.

The sun starts to set, illuminating the area with warm shades of orange and telling us it is time to move on to our last stop: Macao Peninsula.

Influence of urbanisation

The peninsula is the most populous area of Macao and, similar to Taipa, green areas occupy only slightly over 20 per cent of the land. With the exception of some artificial lakes, the opportunity to have contact with nature is limited to Guia Hill and smaller municipal gardens and parks under the management of the Macao Civic and Municipal Affairs Bureau.

We decide to take a walk around Sai Van Lake to reflect on the challenges facing biodiversity conservation efforts in Macao.

Our one‐day tour highlighted the surprisingly high number of plant and animal species that can still be observed in the territory, some with a high conservation priority.

As we look upon Our Lady of Penha Chapel, we agree that just like culture or heritage, the animals and plants of a region are part of its identity. Efforts must be made to balance economic and social development with the preservation of natural habitats, for ourselves and for future generations. Significant steps have been taken in this direction but preserving natural areas in such a small, densely populated territory will not be easy.

While Macao has been steadily growing through land reclamation, the percentage of green areas
per capita has been decreasing, illustrating the intense competition for space that makes it so difficult to expand existing natural spaces. A vividly­coloured common kingfisher (Alcedo atthis) dives at close distance, capturing a small fish, a reminder that for many species, there are no borders between natural and built areas.

Fragmentation of habitats is evident in Macao where natural areas are often interspersed with roads, buildings, and other infrastructures. Some animals, like the kingfisher, cope better with habitat fragmentation than others, such as amphibians or reptiles. As a Chinese softshell turtle (Pelodiscus sinensis) languidly swims close to the lakeshore, we wonder which projects could be proposed to improve biodiversity conservation in Macao.

The territory recently accepted administrative responsibility over 85 square kilometres of its surrounding maritime areas, opening up a unique opportunity to combine terrestrial and marine environmental protection.

Continuing to restore the natural ecosystems of Coloane, and legally protect this island and part of its adjacent waters – in particular the key spots used by the Chinese white dolphins – could be an ambitious and significant nature conservation project for Macao.

A band of little egrets fly off toward mainland China, reminding us that local conservation projects such as this need to be integrated into broader plans in coordination with neighbouring regions. Green corridors, for example, should be considered in order to allow species to move freely between naturally protected areas in different regions. Engaging current and future generations in environmental protection is another key to the success of nature conservation projects.

During our tour, we crossed our paths with many local children swept up in the same sense of awe
as we were when observing animals in their natural habitats. Surely, they will be the future guardians of nature. We can only hope that they will do a better job in protecting our planet than what we have done so far.

Small bats, probably from the Pipistrellus genus, start flying over our heads, indicating it’s time to call it a day – and what a great day it was!