Update on an endangered Philippine cycad species

October 01, 2017

When plant species are threatened to the point that they reach a designation of Critically Endangered, sustaining an understanding of threats requires repeated site visits by knowledgeable biologists to the various sub-populations. The Critically Endangered Cycas wadei, which is known to occur in a single location in the Philippines, was recently evaluated for the contemporary status of the population. The findings and recommendations appear in the current issue of the Journal of Biodiversity & Endangered Species.

This tree is one of 114 described species of Cycas throughout the world and one of 11 Cycas species from the Philippines. The designation of Critically Endangered is primarily based on the fact that the entire population resides in a single, small location on one island. Scientists call plants with these traits "endemic" species. Being restricted to one location increases the vulnerability to any new threats. These threats are amplified by the fact that plants are immobile, and the existing population cannot migrate to new locations like populations of animals.

The study was conducted through a partnership between the University of Guam and the Philippine Native Plants Conservation Society. Ecologist Thomas Marler and taxonomist Ulysses Ferreras carried out the field work. The authors noted that updates on threatened species are often based on general observations. They countered this nonspecific approach by instead implementing empirical methods for determining various population traits. "Establishing plots and applying direct measurements within those plots allowed us to use actual numbers to determine the structure and density of the population," said Marler.

The take-home outcomes of the species update illuminated the most important threats to the future health of Cycas wadei. The two main threats of habitat loss and poaching are not unique to this Cycas species, as many species throughout the world are endangered because of these same threats. The population resides in a grassland that is periodically burned. Fire damage is a third threat that the authors illuminated. Deficiencies in potassium in the soils were identified as the foremost resource constraint on tree growth and development.

Cycas wadei belongs to a group of plants called cycads. This group is comprised of two families and ten genera. Cycads are among the most threatened groups of plants worldwide. Marler and Ferreras hope that the empirical approach they employed can be used for other species updates.

University of Guam

Related Threatened Species Articles from Brightsurf:

Broken promises: Almost 80% of threatened species lack sufficient protection
A failure by governments to deliver on commitments under a global nature conservation treaty, the Convention on Biological Diversity, could have devastating effects.

Wildcats threatened by their domestic cousins
European wildcats, thought to be extinct 50 years ago in the Jura mountains, have since recolonised part of their former territory.

Two new species of parasite discovered in crabs -- discovery will help prevent infection of other marine species
Two new species of parasite, previously unknown to science, have been discovered in crabs in Swansea Bay, Wales, during a study on disease in the Celtic and Irish Seas.

Marine species are outpacing terrestrial species in the race against global warming
Global warming is causing species to search for more temperate environments in which to migrate to, but it is marine species -- according to the latest results of a Franco-American study mainly involving scientists from the CNRS, Ifremer, the Université Toulouse III-Paul Sabatier and the University of Picardy Jules Verne -- that are leading the way by moving up to six times faster towards the poles than their terrestrial congeners.

Directed species loss from species-rich forests strongly decreases productivity
At high species richness, directed loss, but not random loss, of tree species strongly decreases forest productivity.

Much of the earth is still wild, but threatened by fragmentation
Half of the Earth's land surface not covered with ice remains relatively wild -- but many of these 'low human-impact' areas are broken into small, isolated pieces, threatening their future.

Threatened species habitat destruction shows federal laws are broken
Human activities have destroyed more than 7.7 million hectares of threatened species habitat, revealing critical failures with Australia's federal environmental protection laws.

Sea otters have low genetic diversity like other threatened species, biologists report
Sea otters have very low genetic diversity, a UCLA-led team of life scientists reports June 18 in the journal Molecular Biology and Evolution.

Threatened beetles benefit from forest thinning
Wood-living beetles that use oak trees are a species-rich and threatened animal group in modern forestry and agriculture in southern Sweden.

Threatened sturgeon learns for the fitness
An international team led by IGB is providing one of the first proofs of the complex learning behavior of fish in a recent study.

Read More: Threatened Species News and Threatened Species Current Events
Brightsurf.com is a participant in the Amazon Services LLC Associates Program, an affiliate advertising program designed to provide a means for sites to earn advertising fees by advertising and linking to Amazon.com.