Weird Science

The March of the Mantis: How This Insect Is Conquering Poland

Polish version is here

The following article was originally published in the quarterly Ekologia (eng. Ecology) (3/2025):

Ples M., Modliszka zwyczajna - ekspansja gatunku w Polsce (eng. The March of the Mantis: How This Insect Is Conquering Poland), Ekologia (eng. Ecology), Polish Chamber of Ecology, 3 (2025), pp. 27-28

The European mantis (Mantis religiosa), once a rare curiosity in Poland and found only in the country’s warm southern regions, is now spreading quickly. Once considered marginal, this insect has become one of the most striking examples of how climate change is transforming local ecosystems.

Although the mantis remains legally protected and is still listed in the Polish Red Book of Animals as endangered, that status reflects its past more than its present. Over the last two decades, field research and citizen observations have revealed a dramatic northward shift in its range. The species is steadily expanding, challenging long-standing classifications and prompting scientists to redraw distribution maps. Researchers view it as a textbook example of adaptation in a warming world. The mantis’s life cycle depends heavily on temperature, particularly on mild winters that allow its egg cases to survive and hatch in spring. As winters grow shorter and gentler, conditions have become increasingly favorable for this sun-loving predator to move into new territories.

The expansion of the mantis is more than an entomological curiosity. It offers a vivid glimpse into how climate change is reshaping biodiversity and redefining the borders of entire species communities. Understanding this process helps scientists predict which other organisms might follow the same path, using a changing climate to conquer new parts of Europe.

illustration: supplementary material

From Endangered to Expanding

Data collected around the turn of the century reveal a clear and undeniable trend: the European mantis is steadily spreading across Poland. The most likely cause is a series of increasingly mild winters that allow egg cases to survive and hatch successfully when spring arrives. The change has been so dramatic that sightings are now being reported in areas where the species had never been recorded before. Some researchers even question whether it still makes sense to classify the mantis as a highly endangered species across the entire country.

For entomologists, this northward movement is one of the most visible local signs of climate change in action. Recent field studies show that the mantis is not only maintaining stable populations in its traditional habitats but also establishing new ones with remarkable success. Its ability to adapt to a wide range of environments demonstrates a level of ecological flexibility that helps explain its rapid spread.

The phenomenon underscores just how delicate the balance of local ecosystems can be when shaped by global forces. In this context, the mantis has become a kind of “barometer of change”, reflecting the broader effects of a warming climate. Whether this shift should be seen as positive or negative is still uncertain. As with many natural processes, only time and continued research will reveal the full story.

Shifting the Boundaries Northward

Until the late 20^th century, the European mantis (Mantis religiosa) was found in Poland only in a few isolated areas. Its northern limit stopped at the Sandomierz Basin, reflecting how closely the species was tied to the country’s warmest southern regions. That pattern began to change after 2000. Since then, the number of recorded sites has grown steadily, and after 2015 the mantis entered a period of rapid expansion across central Poland, including Greater Poland, Mazovia, and the Kuyavian-Pomeranian region.

Research conducted between 1995 and 2021 provides solid numerical evidence of the scale of this transformation. In just 26 years, the mantis’s range in Poland increased from 3 percent to an impressive 77 percent of the country’s area. This growth is a clear sign of active and natural range expansion rather than isolated or accidental observations. Today, the species remains uncommon only in the far north, while sightings have already been reported in Lithuania, confirming that its range continues to shift northward beyond historical boundaries.

One of the main migration routes for the species likely follows the Vistula River corridor. Strong populations have become established in the Middle Vistula Valley and in the Kozienice Forest region, supporting this idea. Data collected by the Polish Entomological Society, along with hundreds of observations from amateur naturalists, indicate that the mantis is now one of the fastest-spreading insect species in Poland. Its northward expansion continues and is being carefully documented year after year.

Habitat Preferences

The European mantis is a thermophilic insect, meaning its life cycle and survival depend on high temperatures—a key factor behind its northward expansion. Its preferred habitats include dry, sunny environments such as meadows, clearings, heathlands, and open pine forest edges. Yet the species has shown a remarkable ability to adapt to a range of conditions, including peat bogs and xerothermic grasslands, proving its strong ecological flexibility.

In search of warmth and suitable living spaces, mantises are increasingly venturing into urban areas, which act as so-called “heat islands”—places where temperatures remain higher than in the surrounding countryside. As a result, these insects are now often spotted on sunlit parking lots, in suburban gardens, and even clinging to building walls in city centers. Paradoxically, they are sometimes easier to find in these artificial environments than in their natural habitats, which has led to a growing number of casual sightings reported by residents.

Flower meadows and rarely mown green belts within cities have become especially attractive to them, offering both abundant prey and safe spots for laying eggs. In this way, the mantis has quietly adapted to a world shaped by humans, turning urban landscapes into unexpected havens for survival and growth.

illustration: supplementary material

Biology and Protection

The European mantis is a thermophilic insect, which means its life cycle and survival depend on high temperatures, a key factor behind its northward spread. Its preferred habitats are dry, sunny areas such as meadows, clearings, heathlands, and open edges of pine forests. At the same time, the species has shown an impressive ability to adapt to many different environments, including peat bogs and xerothermic grasslands, demonstrating its remarkable ecological flexibility.

In search of warmth and suitable living spaces, mantises are increasingly venturing into urban areas that function as “heat islands”, where temperatures stay higher than in the surrounding countryside. As a result, these insects are now often seen on sunlit parking lots, in home gardens, and even clinging to walls in city centers. Paradoxically, they are sometimes easier to find in these human-made settings than in their natural habitats, which has led to a surge in casual sightings reported by city residents.

Flower meadows and rarely mown green belts within cities have become particularly appealing to mantises, providing abundant prey, safe spots for laying eggs, and plenty of hiding places. In this way, the mantis has quietly adjusted to a world shaped by people, turning urban landscapes into unexpected refuges for survival and growth.

Conclusion

The rapid spread of the European mantis in Poland is a clear and well-documented example of how climate change, especially milder winters, can shape the population dynamics and distribution of heat-loving species. Although this process is natural and sightings are becoming increasingly frequent, the mantis remains a protected species that must continue to be monitored until its populations stabilize across the country.

Its growing presence in new areas, including densely populated cities, provides strong evidence of its ability to adapt to changing environmental conditions. Ongoing research, supported by both scientists and citizen observers, will be crucial for understanding the mechanisms driving this remarkable expansion. The increasing number of urban sightings, from flower meadows to sunny walls and warm sidewalks, is offering valuable clues about how this iconic insect is quietly redrawing the map of its northern range.

Weird Science

The March of the Mantis: How This Insect Is Conquering Poland

From Endan­ge­red to Expan­ding

Shi­fting the Boun­da­ries Nor­th­ward

Habi­tat Pre­fe­ren­ces

Bio­logy and Pro­tec­tion

Conc­lu­sion

From Endangered to Expanding

Shifting the Boundaries Northward

Habitat Preferences

Biology and Protection

Conclusion