Science for Saving Species Research findings factsheet Project 3.1 Factsheet: A Threatened Mammal Index for Australia Research in brief How can the index be used? This project is developing a For the first time in Australia, an for threatened plants are currently Threatened Species Index (TSX) for index has been developed that being assembled. Australia which can assist policy- can provide reliable and rigorous These indices will allow Australian makers, conservation managers measures of trends across Australia’s governments, non-government and the public to understand how threatened species, or at least organisations, stakeholders and the some of the population trends a subset of them. In addition to community to better understand across Australia’s threatened communicating overall trends, the and report on which groups of species are changing over time. It indices can be interrogated and the threatened species are in decline by will inform policy and investment data downloaded via a web-app to bringing together monitoring data. decisions, and enable coherent allow trends for different taxonomic It will potentially enable us to better and transparent reporting on groups or regions to be explored relative changes in threatened understand the performance of and compared. So far, the index has species numbers at national, state high-level strategies and the return been populated with data for some and regional levels. Australia’s on investment in threatened species TSX is based on the Living Planet threatened and near-threatened birds recovery, and inform our priorities Index (www.livingplanetindex.org), and mammals, and monitoring data for investment. a method developed by World Wildlife Fund and the Zoological A Threatened Species Index for mammals in Australia Society of London. The TSX has been designed to be a dynamic Different taxonomic groups can be Profile and Threats Database and the tool to which new monitoring data explored individually in the Threatened international IUCN Red List as of July are added and examined annually. Species Index. Here, we present the 2019 to make a decision about the national Threatened Mammal Index currently listed taxa. (TMX) for the first time (Figure 1A). In Data on these mammal taxa come its first iteration, this index incorporates from fixed sites where they have been data from 57 threatened and near- repeatedly monitored in a systematic threatened mammal taxa (Near and standardised way. For some of Threatened, Vulnerable, Endangered the terrestrial sites, the data custodians or Critically Endangered under the provided information on whether they EPBC Act and/or IUCN – see Table 1). have been intensively managed and This represents about 39% of Australia’s how. This information allowed us to threatened and near-threatened look at the trend across all monitored mammals (143 taxa, which counts both sites, which is the overall Threatened species and subspecies) and comprises Mammal Index (Figure 1), but also to drill 53 terrestrial (five volant and 48 non- down to look at the trends for: volant) mammals, one bat, and four 1. Sites subject to any management marine mammals (Table 1). We used (e.g., introduced predator-free information from the Australian Species havens/islands and other A Threatened Species Index for mammals in Australia (continued) dedicated conservation index. The reintroduced population Changes in the index are proportional management) (Figure 2), trends may skew the overall result – a value of 0.5 indicates the multi- 2. Sites without introduced predators for a taxon and show the population taxon relative abundance is 50% below (islands and fenced exclosures) as stable or increasing while in fact the baseline value; a value of 1.5 (Figure 3), and the extant population outside of the indicates 50% above baseline. predator-free safe havens continues For the index on all sites where 3. Sites with no (known) targeted to decline, and thus need to be Australian threatened and near- management (Figure 4). examined carefully. threatened mammals were monitored, The division of sites/populations has The index itself shows the estimated the TMX value in 2016 based on the been made solely on information yearly change in relative abundance current data is 0.62. This suggests that provided by the custodians. This of threatened and near-threatened the relative abundance of threatened separation into subindices based on mammal taxa in relation to a baseline and near-threatened mammals for the type of intensive management year, for which 1995 was chosen, which we have information has is important especially for mammals where the index is set to 1.0. This decreased by 38% between 1995 and monitored after being reintroduced baseline year was chosen because 2016. While the overall index value in into fenced or predator-free island very few of the ongoing monitoring 2016 is 0.62, individual taxa have TMX areas. These areas are often more programs originated before 1995. values between 0.34 (a 66% decrease) intensively monitored than extant However, later baseline years are and 1.08 (a 8% increase) (Figure 1A). It populations, have fewer threats, also available to support the specific is expected that more data (and taxa) and have the potential to significantly needs of conservation managers and will be added as they become available bias the population trends in the overall can be selected via the web-app. each year, allowing the index to grow. What should we know about the data? This overall index on all monitored sites and the northern part of the Northern The index that includes only island is based on 1186 time series (defined Territory, but there is little or no and other predator-free sites is based as sites where data on a taxon are representation yet of monitoring on 23 time series and 15 mammal recorded using the same methodology data from New South Wales and the taxa. With a TMX value of 6.00, it and a consistent monitoring effort Australian Capital Territory. There are shows an average increase of 500% though time) across these 57 taxa. limited taxon datasets for Tasmania and between 2000 and 2016 (Figure 3). Data quality was maximised by: 1) the arid zone (Figure 1B). The number The index corresponding to sites with checking whether each dataset had of sites monitored that met the TMX no (known) targeted management been produced by standardised criteria (Figure 1C) has substantially monitoring; and 2) by sending surveys increased since around 1995, while the contains the majority of data on sites on 127 eligible datasets to custodians number of taxa monitored increased and taxa. This index is based on 1031 and requesting them to assess the from 17 in 1995 to 50 in 2013 (Figure time series and 32 mammal taxa. trends produced for their datasets. 1D). In combination, this has resulted The TMX value in 2016 is 0.40 which Feedback was received for 74% of the in a large increase in the time series indicates a 60% decrease on average datasets. Only time series that had been available: from 353 in 1995 to 806 in relative mammal abundance produced by standardised monitoring in 2013. between 1995 and 2016 (Figure 4). and with a minimum length of two The index containing data on sites As more high-quality data become years, collected between 1995 and that were subject to any management available they can be added, making 2016 inclusive, were used for index such as introduced predator-free the index more powerful, meaningful calculation. Sub-trends of the overall havens/islands and other dedicated and representative. Increasing trend (e.g., for marine mammals) conservation management (i.e., the number of taxa, regions and can be calculated if data on at least sustained predator baiting and functional groups monitored would three taxa are available. ecological fire management) has 155 strengthen the value of the index. The data underlying the national time series with data on 29 mammal Ongoing long-term monitoring index mostly derive from monitoring taxa. This index has a 2016 value programs allow for continuing programs in eastern Queensland, of 1.46, which corresponds to an capability to track changes in the southern Victoria, coastal and inland increase of 46% between 1995 and relative abundance of threatened South Australia, Western Australia, 2016 (Figure 2). and near-threatened mammal taxa. Interpretational issues and constraints • This composite index only includes monitoring opportunities to • Some mammal subgroups, such data for threatened and near- increase the comprehensiveness as bats and rodents, are still threatened mammal taxa provided of representation of threatened underrepresented. by the custodians endeavouring and near-threatened mammal • The proportional representation of to meet the TMX criteria supplied. taxa (see Table 1). threatened and near-threatened Inspection of these data indicate • There were limited appropriate mammal taxa, and spatial they are biased to the coastal areas monitoring data for remote areas coverage, is low in comparison of most states and are sparse for available for inclusion in the to data on threatened and near- the arid zone. The index can be index to 2016. threatened birds. (Threatened useful for also identifying strategic Bird Index). Fig 1: The A 57 taxa B 1186 time series Threatened Mammal Index (TMX) including data from all sites where threatened and near- threatened mammal taxa were monitored C D Figure 1: A) The Threatened Mammal Index (TMX) including data from all sites where threatened and near-threatened mammal taxa were provided. The blue line shows the change in mammal abundance relative to the baseline year of 1995, where the index is set to 1.0. The grey cloud shows the range of trends for the individual taxa that make up the overall multi-taxon index. It can be seen as the variability between single-taxon trends that contribute to the composite (i.e., it is not statistical confidence).