A new map of the grassland predator community in Australia reveals that the number of species found in the country’s national parks and conservancies is on the rise.
The National Parks and Wildlife Service (NPWS) released the results of a study of 4,000 locations in the national parks in Victoria and Western Australia.
While a lot of the country is covered by grassland predators, more than 700 species are found in all the national forests and conservation areas, the report said.
“We found that between the years 2000 and 2015, the number in national parks increased by 2.7 million,” said NPWS Deputy Chief Scientist, Mark McQuillan.
The number of grassland vertebrates and vertebrate-like invertebrates in national forests increased from 3.4 million in 2000 to 4.3 million in 2015. “
This trend continued into the 21st century, with the decline in species in national park areas and the loss of habitat to grassland grazers.”
The number of grassland vertebrates and vertebrate-like invertebrates in national forests increased from 3.4 million in 2000 to 4.3 million in 2015.
In Victoria, the numbers of grasslands carnivores have increased from 4.2 million in 1990 to 5.1 million in 2016.
There was a decrease in the number and abundance of terrestrial carnivore species in the National Parks, but the trend continued in Western Australia, where the number was down from 4 million in 2010 to 2.4 at the end of the study period.
“This is not surprising, given that the grasslands are now undergoing the effects of habitat fragmentation and degradation caused by climate change, but we still see a clear trend in the numbers,” Mr McQuillo said.
The report also found that the proportion of species in National Parks increased in the 21 years from 2000 to 2015, but that the percentage of grasses in national areas has remained relatively stable.
Of the 4.5 million species found, about 1.3 percent of the total were terrestrial, the remaining 85 percent were invertebrate, with insects, plants and birds accounting for a quarter of all species.
About 40 percent of species were terrestrial in the most recent survey in 2015, and in 2050 that number is expected to increase to 70 percent.
Dr John F. Smith, a Senior Lecturer in the School of Biological Sciences at the University of Western Australia’s Institute of Biological Studies, said while it was a “big surprise” that the numbers had been stable, there was still a good chance of finding more species in parks and other protected areas in the future.
“What is surprising about the numbers is the increase in the proportion found in national Parks,” he said.
“The species found there are largely terrestrial and there are a few invertebras and some marine and freshwater invertebridges, but not all of them.”
For example, the largest terrestrial carnivorous fish in the world is found in Western Australian National Parks.
“[This is] a result of habitat degradation and a shift to large-scale development, but this also means that other predators are becoming more numerous.
For example the Australian brown trout has increased in numbers in the state over the past 20 years, although the population has fallen in recent years due to the loss or degradation of habitat.”
Dr Smith said the report showed that more research was needed to understand the factors that contribute to the increased abundance of grass and the decline of other terrestrial species.
“It will take more work to understand how the loss and fragmentation of habitats is affecting the growth of carnivores,” he added.