by Zarelle Glen Dorothy A. Villanzana | March 4, 2022
The United Nations General Assembly had decided to proclaim every March 3 as World Wildlife Day, a celebration which gives significance to all the various wonderful fauna and flora in the wild, and a reminder of the urgent need to fight against wildlife crime and human-induced reduction of species, which results to wide-ranging economic, environmental, and social impacts.
It may not be as well-known to the general public, but invasive alien species (IAS) are actually the biggest causes of worldwide biodiversity loss, second to habitat destruction. Any plant or animal species brought into an entirely unfamiliar environment by human intervention, accidental or not, is considered nonnative, but once it starts eliminating native species in the same area, it becomes invasive.
To put matters into context, the golden apple snail which was once seen to be helpful for increasing Filipino farmers’ income and supplying them with protein, soon started taking away their livelihood by damaging rice farms in the northwestern parts of Luzon. The Department of Environment and Natural Resources’ (DENR) Ecosystems Research and Development Bureau (ERDB) said the proliferation of IAS could consequently wipe out endemic and native species of a country, thus, it is important to address this issue if we are to fight for their conservation and maintain an ecological balance.
The Philippines is 36th in the world in terms of the number of invasive species, and first in Southeast Asia. Just like the golden apple snail, other invasive species are still presently affecting our ecosystems today, even the familiar ones such as the Ipil-ipil tree, and the ever-amusing Makahiya plant.
Water hyacinth (Eichhornia crassipes)
Native to South America, particularly in the Amazon Basin, these floating aquatic plants are considered invasive as they are inedible and cause flooding. They clog waterways, impede boat transport and fishing activities, and reduce phytoplankton growth and food of fish, thereby affecting fishing and aquaculture activities in major lakes like that in the Bicol Region. Thousands of water hyacinths reemerge every rainy season, thus cleaning them up becomes a yearly struggle.
Ipil-ipil (Leucaena leucocephala)
Introduced from tropical America during the Spanish colonial period, the Ipil-ipil tree is the only invasive tree species reported in several databases. It has grown fast over the entire country and has adapted to the Philippine climate pretty well since it is a type of tropical rainforest plant. At first, it was welcomed warmly as it made good firewood and provided shade for understory crops. Now, it is considered invasive since it forms pure stands (a plant population consisting largely of members of one species) which are difficult to eradicate and thus make the land unusable.
Sensitive plant or “Makahiya” (Mimosa pudica)
Native to South America, M. pudica is considered a serious pest of crops and pastures in the tropics. It is recognized as among the 10 worst weeds in French Polynesia, Guam, the Solomon Islands, and Tonga. In the Philippines, it is considered a serious weed in lawns, rice fields, and soybean crop fields. It easily becomes a fire hazard once it dies, and it may also prevent the regeneration of other species, also reportedly killing out all other plants. Its effects on biodiversity are yet quite limited, though, but it is worth knowing that it is invasive.
Chinese softshell turtle (Pelodiscus sinensi)
Once considered an exotic pet, they gained the title of being a menace to fishpond owners in Central Luzon as they have become pests, feeding voraciously on various aquatic fauna. In 2013, they were considered pests in the fish industry of Pampanga, Bulacan, and Bataan. Some fishermen and fishpond owners from various towns in Pampanga also likened the situation to the golden kuhol that distressed the rice farmers in the 80s.
Golden apple snail (Pomacea canaliculata or the “golden kuhol”)
Imported from South America via Taiwan in the early 1980s, the species was first meant to be bred and sold as food because of their high protein content and rapid reproduction rate. Unfortunately, the intention had not been met, instead, these snails escaped and ended up in Luzon’s rice fields, the best place for them to breed, multiplying exceedingly at about 500 eggs a week.
Cane toads (Rhinella marina)
Natively known as “Marine Toads” or Giant Toads” in South America, cane toads were brought to the Philippines in 1930 by sugarcane farmers who thought the animal could help them eliminate pests in their fields, only to find out later that they would become pests themselves. These toads eat every animal they could get ahold of, additionally, they are poisonous to touch and deadly to be eaten by bigger animals. Soon enough, these invasive toads became the most common amphibian in the Philippines.
Listed above are just some of the multitude of invasive alien species in the Philippines. Although most have stayed in the country for a long time already, it cannot be denied how they still affect our environment, not to mention the livelihood of many Filipinos which our economy depends upon. Many operations have been undertaken to address these issues, but truly, it is not an easy task. Ultimately, prevention is always better than cure, and having prior information about this quiet issue may give us the ability to manage IAS. We could report sightings of invasive alien species in our areas once we recognize them, and to prevent the extinction of our native fauna and flora, planting them ourselves would also definitely help us win the combat for their conservation.
FlipScience. (2019, December 28). Far from home: The problem of invasive species in Southeast Asia. FlipScience – Top Philippine Science News and Features for the Inquisitive Filipino. https://www.flipscience.ph/plants-and-animals/invasive-species-southeast-asia/
J. (2019, September 11). Cane Toad (palakang-tubó). Animals of Tanay. https://animalsoftanay.home.blog/2019/04/30/cane-toad-palakang-tubo/#:%7E:text=Cane%20Toads%20come%20from%20South,other%20pests%20in%20their%20fields.
Mayuga, J. L. (2019, July 14). Invasive alien species: A serious threat to ecosystems, biodiversity | Jonathan L. Mayuga. BusinessMirror. Retrieved 2022, from https://businessmirror.com.ph/2019/07/15/invasive-alien-species-a-serious-threat-to-ecosystems-biodiversity/
Mimosa pudica (sensitive plant). (2021, November 16). Invasive Species Compendium. https://www.cabi.org/isc/datasheet/34202
Spratley, M. (2021, April 6). 10 Ways You Can Prevent the Spread of Invasive Species. Alliance for the Chesapeake Bay. https://www.allianceforthebay.org/2018/02/10-ways-you-can-prevent-the-spread-of-invasive-species/