Climate Change to Drive Venomous Snakes Toward Populated Coastlines, Study Finds
A groundbreaking global study has revealed that climate change will force venomous snakes to migrate away from arid interiors and toward densely populated coastal regions. This shift significantly increases the risk of deadly encounters for millions of people worldwide as rising temperatures render their current habitats unsuitable.
Global Migration Patterns and Increased Human Exposure
Published in the journal PLOS Neglected Tropical Diseases, the research models the habitats of all 508 medically important venomous snake species. It projects how their ranges will shift by 2050 and 2090, predicting broad movements toward higher latitudes and more heavily populated areas.
In Australia, this trend is expected to be particularly pronounced along the east coast, where snakes will move from the arid centre into more densely populated southern regions. Globally, the highest overlaps between snake and human populations currently exist in Sub-Saharan Africa, South Asia, and Southeast Asia—areas already bearing the greatest burden from snakebites.
These overlaps are projected to increase substantially across the Indian subcontinent, eastern North America, and parts of China as global temperatures rise. The four snake species with the highest predicted increases in human exposure by 2090 are:
- The black-necked spitting cobra
- The many-banded krait
- The cottonmouth
- The copperhead
Addressing a Neglected Tropical Disease
The study highlights that snakebite is considered a neglected tropical disease due to limited data on exact distribution and bite incidents, despite causing enormous burdens in many countries. Snakebites kill approximately 138,000 people and cause 400,000 disabilities annually, primarily affecting poor rural communities in low- and middle-income nations. The World Health Organization aims to reduce this burden by 50% by 2030.
This research is the first to model all medically important venomous snakes at a resolution of around one kilometre, including species with sparse data. It draws on public and private databases, citizen science platforms, museum records, scientific literature, and expert observations, all vetted by an international panel of about 30 specialists.
Human Behaviour and Environmental Factors
Human behaviour adds complexity to the risk landscape. Farm workers without protective equipment face far greater exposure to snakes than those using machinery. Additionally, floods driven by extreme weather events are known to increase snakebite incidence by displacing both humans and snakes.
The study's predictions can guide critical public health measures, such as where to stockpile antivenoms, how to resource health facilities, and where to focus conservation efforts. "The first step in helping victims of snakebite is to know where people and snakes interact the most," the researchers note, emphasising the need to target support to remote rural communities.
Conservation Concerns and Range Contractions
Not all snake species will expand their ranges. Many in the Congo and Amazon basins and Southeast Asia, particularly those with already small ranges, are predicted to see net decreases in range size, raising significant conservation concerns. The wide-ranging puff adder, which currently causes numerous bites across Africa, is also expected to lose much of its current habitat.
"Our predictions can be used to decide where to stockpile which antivenom, how to ensure adequate capacity of individual health facilities, how to improve health care accessibility of remote at-risk communities, and where to focus conservation efforts for threatened snake species," the researchers state.
Broader Climate Context and Emergency Warnings
These findings emerge as the UN warns the global climate system is in a state of emergency. The World Meteorological Organization’s State of the Global Climate 2025 report found the 11 years from 2015 to 2025 were the hottest on record, with 2025 about 1.43°C above pre-industrial levels.
UN secretary general António Guterres declared every key climate indicator is "flashing red", noting the planet's addiction to fossil fuels is destabilising both the climate and global security. The rate of ocean warming between 2005 and 2025 more than doubled compared to 1960–2005.
WMO secretary general Celeste Saulo added that human activities are increasingly disrupting the natural equilibrium in ways that will be felt for centuries. The snake study uses a worst-case emissions scenario for its projections, arguing that planning for the most severe outcome offers the best basis for public health preparation.
