Using Threat Maps To Inform Conservation Efforts

Around the world, we are experiencing a rapid loss in biodiversity, with some of it happening at the rate of prior mass extinction events. Plant and animal diversity contribute to climate regulation, clean water, clean air, and access to food. So, biodiversity loss doesn’t just impact the individuals who are dying but also indirectly harms all living beings, humans included. 

Currently, human activities have the largest impact on biodiversity loss. Therefore it’s important to understand how we can minimize human-driven threats.

“Threat maps” show the geographic locations where specific human activities have negative impacts on wild terrestrial, marine, and freshwater species. They are important tools scientists and animal advocates can use to inform which interventions are most likely to reduce harm. While each threat map is useful in and of itself, the researchers in this study note that a database of maps would be helpful to highlight conservation patterns and knowledge gaps.

For this reason, the authors of this study created a database of threat maps showing existing threats to wild animal and plant species around the world. They conducted an extensive search of threat mapping research published between 2000 and 2020 and came up with 1,069 papers. These threat maps showed only human-caused problems, both direct (e.g., residential development) and indirect (e.g., climate change-induced storms and droughts). 

Threat Map Findings

By aggregating and reviewing all relevant maps, the researchers were able to identify the following patterns and insights:

• Species Representation: There were far more threat maps studying terrestrial species (700 maps) than marine (282) or freshwater species (171). Most maps focused only on animals (664 papers) rather than plants (193).
• Animal Representation: Mammals have received the most research (287 maps), followed by birds (171), fish (144), invertebrates (111), reptiles (86), and amphibians (70). According to the authors, mammals have also received the most in-depth and single-species research compared to other animals.
• Global Representation: 75% of all threat maps were conducted on a national or local (rather than international) scale. Threat maps have been developed across 144 countries and 160 marine territories, but 50% of the world’s nations had five maps or fewer. Most research represented Western countries and a small number of large, rapidly-developing countries.
• Threat Occurrences: The most common threats studied across all maps included: so-called “invasive,” non-native species or diseases (187 maps), fishing and aquatic resource use (184), road and railway infrastructure (172), residential and urban development (170), non-timber crop agriculture (142), unspecified agriculture (114), hunting (102), and animal farming (100). Other, lesser-studied threats included so-called “problematic” native species (9), droughts brought about by climate change (8), so-called “problematic” species of unknown origin (5), storms or flooding brought about by climate change (4), introduced genetic material (4), flight paths (2), and viral diseases (1).
• Threat Themes: When threats were grouped by theme, the most prevalent ones were agriculture and aquaculture (323 maps), followed by biological resource exploitation (314), residential and commercial development (280), and transport and utility lines (268). So-called “problematic” species, pollution, energy and mining, and climate change were addressed in fewer maps, while maps about human intrusion and disturbance and natural system modification appeared least frequently.

The authors point out a few limitations of their research. Most notably, they only assessed literature in English, which means there could be helpful, non-English threat maps excluded from the results. This may also be why the majority of studies focused on the global West.

Implications For Animal Advocates

Advocates can use existing threat maps as scientific evidence to guide (or justify) their recommendations. For example, the authors note that global road and rail network lengths will likely increase by 60% by the year 2050. Threat maps demonstrate their impact on species extinction, meaning these findings can inform decisions about the locations and processes used to develop new transport infrastructure. Similarly, knowing that agriculture and aquaculture is the most common threat to wild species is important information for farmed animal advocacy campaigns.

In areas where there is threat map scarcity, advocates can also highlight biases. These include the underrepresentation of African, South American, and Asian geographies as well as marine and saltwater species. Finally, there is a need to explore the interconnected nature of wild species and the threats that face them. For example, maps that capture land-based threats to the marine environment or interactions between two or more threats could provide valuable conservation insights.