Matsu removes invasive plants to protect Formosan sika deer habitat

馬祖清除入侵植物以保護梅花鹿棲息地

TAIPEI (Taiwan News) — The Lienchiang County Government has been removing invasive Jerusalem cherry plants since 2021 to support the survival of nearly 280 Formosan sika deer on Daqiu Island.

Jerusalem cherry is a toxic plant with few natural predators on the island. Its rapid spread competes with native vegetation, disrupting the ecosystem and reducing food sources for deer.

Tunghai University Landscape Architecture Professor Tsou Chun-wei (鄒君瑋) said migratory birds likely spread the plant by eating its seeds and excreting them onto the island, per CNA.

The county government is running a visitor program from Saturday through Oct. 12 to help remove the plants. Participants who clear more than 20 will be eligible for prizes. Since the campaign began, about 50,000 Jerusalem cherry plants have been removed.

Tsou noted that while herbicides could be used, they risk harming the deer. Instead, removed plants are burned into charcoal and returned to the soil as fertilizer, while butter daisy seeds are sown to prevent regrowth.

Daqiu Island, once home to 300 residents and a military garrison, was abandoned following population outflow. In 1980, Taipei Zoo gifted Formosan sika deer to the county government, which released them on the island.

The deer have since adapted and reproduced, with the current population several times larger than when first introduced. The county has also assigned a veterinary team for year-round health monitoring and rescue. From January to April, nine deer deaths were recorded, mostly older animals that died of natural causes.